security/selinux/hooks.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  Security-Enhanced Linux (SELinux) security module
   4  *
   5  *  This file contains the SELinux hook function implementations.
   6  *
   7  *  Authors:  Stephen Smalley, <stephen.smalley.work@gmail.com>
   8  *            Chris Vance, <cvance@nai.com>
   9  *            Wayne Salamon, <wsalamon@nai.com>
  10  *            James Morris <jmorris@redhat.com>
  11  *
  12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14  *                                         Eric Paris <eparis@redhat.com>
  15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16  *                          <dgoeddel@trustedcs.com>
  17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18  *      Paul Moore <paul@paul-moore.com>
  19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  21  *  Copyright (C) 2016 Mellanox Technologies
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/kd.h>
  26 #include <linux/kernel.h>
  27 #include <linux/kernel_read_file.h>
  28 #include <linux/errno.h>
  29 #include <linux/sched/signal.h>
  30 #include <linux/sched/task.h>
  31 #include <linux/lsm_hooks.h>
  32 #include <linux/xattr.h>
  33 #include <linux/capability.h>
  34 #include <linux/unistd.h>
  35 #include <linux/mm.h>
  36 #include <linux/mman.h>
  37 #include <linux/slab.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/proc_fs.h>
  40 #include <linux/swap.h>
  41 #include <linux/spinlock.h>
  42 #include <linux/syscalls.h>
  43 #include <linux/dcache.h>
  44 #include <linux/file.h>
  45 #include <linux/fdtable.h>
  46 #include <linux/namei.h>
  47 #include <linux/mount.h>
  48 #include <linux/fs_context.h>
  49 #include <linux/fs_parser.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/inet_connection_sock.h>
  57 #include <net/net_namespace.h>
  58 #include <net/netlabel.h>
  59 #include <linux/uaccess.h>
  60 #include <asm/ioctls.h>
  61 #include <linux/atomic.h>
  62 #include <linux/bitops.h>
  63 #include <linux/interrupt.h>
  64 #include <linux/netdevice.h>    /* for network interface checks */
  65 #include <net/netlink.h>
  66 #include <linux/tcp.h>
  67 #include <linux/udp.h>
  68 #include <linux/dccp.h>
  69 #include <linux/sctp.h>
  70 #include <net/sctp/structs.h>
  71 #include <linux/quota.h>
  72 #include <linux/un.h>           /* for Unix socket types */
  73 #include <net/af_unix.h>        /* for Unix socket types */
  74 #include <linux/parser.h>
  75 #include <linux/nfs_mount.h>
  76 #include <net/ipv6.h>
  77 #include <linux/hugetlb.h>
  78 #include <linux/personality.h>
  79 #include <linux/audit.h>
  80 #include <linux/string.h>
  81 #include <linux/mutex.h>
  82 #include <linux/posix-timers.h>
  83 #include <linux/syslog.h>
  84 #include <linux/user_namespace.h>
  85 #include <linux/export.h>
  86 #include <linux/msg.h>
  87 #include <linux/shm.h>
  88 #include <uapi/linux/shm.h>
  89 #include <linux/bpf.h>
  90 #include <linux/kernfs.h>
  91 #include <linux/stringhash.h>   /* for hashlen_string() */
  92 #include <uapi/linux/mount.h>
  93 #include <linux/fsnotify.h>
  94 #include <linux/fanotify.h>
  95 #include <linux/io_uring/cmd.h>
  96 #include <uapi/linux/lsm.h>
  97
  98 #include "avc.h"
  99 #include "objsec.h"
 100 #include "netif.h"
 101 #include "netnode.h"
 102 #include "netport.h"
 103 #include "ibpkey.h"
 104 #include "xfrm.h"
 105 #include "netlabel.h"
 106 #include "audit.h"
 107 #include "avc_ss.h"
 108
 109 #define SELINUX_INODE_INIT_XATTRS 1
 110
 111 struct selinux_state selinux_state;
 112
 113 /* SECMARK reference count */
 114 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 115
 116 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 117 static int selinux_enforcing_boot __initdata;
 118
 119 static int __init enforcing_setup(char *str)
 120 {
 121         unsigned long enforcing;
 122         if (!kstrtoul(str, 0, &enforcing))
 123                 selinux_enforcing_boot = enforcing ? 1 : 0;
 124         return 1;
 125 }
 126 __setup("enforcing=", enforcing_setup);
 127 #else
 128 #define selinux_enforcing_boot 1
 129 #endif
 130
 131 int selinux_enabled_boot __initdata = 1;
 132 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 133 static int __init selinux_enabled_setup(char *str)
 134 {
 135         unsigned long enabled;
 136         if (!kstrtoul(str, 0, &enabled))
 137                 selinux_enabled_boot = enabled ? 1 : 0;
 138         return 1;
 139 }
 140 __setup("selinux=", selinux_enabled_setup);
 141 #endif
 142
 143 static int __init checkreqprot_setup(char *str)
 144 {
 145         unsigned long checkreqprot;
 146
 147         if (!kstrtoul(str, 0, &checkreqprot)) {
 148                 if (checkreqprot)
 149                         pr_err("SELinux: checkreqprot set to 1 via kernel parameter.  This is no longer supported.\n");
 150         }
 151         return 1;
 152 }
 153 __setup("checkreqprot=", checkreqprot_setup);
 154
 155 /**
 156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 157  *
 158  * Description:
 159  * This function checks the SECMARK reference counter to see if any SECMARK
 160  * targets are currently configured, if the reference counter is greater than
 161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 163  * policy capability is enabled, SECMARK is always considered enabled.
 164  *
 165  */
 166 static int selinux_secmark_enabled(void)
 167 {
 168         return (selinux_policycap_alwaysnetwork() ||
 169                 atomic_read(&selinux_secmark_refcount));
 170 }
 171
 172 /**
 173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 174  *
 175  * Description:
 176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 177  * (1) if any are enabled or false (0) if neither are enabled.  If the
 178  * always_check_network policy capability is enabled, peer labeling
 179  * is always considered enabled.
 180  *
 181  */
 182 static int selinux_peerlbl_enabled(void)
 183 {
 184         return (selinux_policycap_alwaysnetwork() ||
 185                 netlbl_enabled() || selinux_xfrm_enabled());
 186 }
 187
 188 static int selinux_netcache_avc_callback(u32 event)
 189 {
 190         if (event == AVC_CALLBACK_RESET) {
 191                 sel_netif_flush();
 192                 sel_netnode_flush();
 193                 sel_netport_flush();
 194                 synchronize_net();
 195         }
 196         return 0;
 197 }
 198
 199 static int selinux_lsm_notifier_avc_callback(u32 event)
 200 {
 201         if (event == AVC_CALLBACK_RESET) {
 202                 sel_ib_pkey_flush();
 203                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 204         }
 205
 206         return 0;
 207 }
 208
 209 /*
 210  * initialise the security for the init task
 211  */
 212 static void cred_init_security(void)
 213 {
 214         struct task_security_struct *tsec;
 215
 216         tsec = selinux_cred(unrcu_pointer(current->real_cred));
 217         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 218 }
 219
 220 /*
 221  * get the security ID of a set of credentials
 222  */
 223 static inline u32 cred_sid(const struct cred *cred)
 224 {
 225         const struct task_security_struct *tsec;
 226
 227         tsec = selinux_cred(cred);
 228         return tsec->sid;
 229 }
 230
 231 static void __ad_net_init(struct common_audit_data *ad,
 232                           struct lsm_network_audit *net,
 233                           int ifindex, struct sock *sk, u16 family)
 234 {
 235         ad->type = LSM_AUDIT_DATA_NET;
 236         ad->u.net = net;
 237         net->netif = ifindex;
 238         net->sk = sk;
 239         net->family = family;
 240 }
 241
 242 static void ad_net_init_from_sk(struct common_audit_data *ad,
 243                                 struct lsm_network_audit *net,
 244                                 struct sock *sk)
 245 {
 246         __ad_net_init(ad, net, 0, sk, 0);
 247 }
 248
 249 static void ad_net_init_from_iif(struct common_audit_data *ad,
 250                                  struct lsm_network_audit *net,
 251                                  int ifindex, u16 family)
 252 {
 253         __ad_net_init(ad, net, ifindex, NULL, family);
 254 }
 255
 256 /*
 257  * get the objective security ID of a task
 258  */
 259 static inline u32 task_sid_obj(const struct task_struct *task)
 260 {
 261         u32 sid;
 262
 263         rcu_read_lock();
 264         sid = cred_sid(__task_cred(task));
 265         rcu_read_unlock();
 266         return sid;
 267 }
 268
 269 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 270
 271 /*
 272  * Try reloading inode security labels that have been marked as invalid.  The
 273  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 274  * allowed; when set to false, returns -ECHILD when the label is
 275  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 276  */
 277 static int __inode_security_revalidate(struct inode *inode,
 278                                        struct dentry *dentry,
 279                                        bool may_sleep)
 280 {
 281         struct inode_security_struct *isec = selinux_inode(inode);
 282
 283         might_sleep_if(may_sleep);
 284
 285         if (selinux_initialized() &&
 286             isec->initialized != LABEL_INITIALIZED) {
 287                 if (!may_sleep)
 288                         return -ECHILD;
 289
 290                 /*
 291                  * Try reloading the inode security label.  This will fail if
 292                  * @opt_dentry is NULL and no dentry for this inode can be
 293                  * found; in that case, continue using the old label.
 294                  */
 295                 inode_doinit_with_dentry(inode, dentry);
 296         }
 297         return 0;
 298 }
 299
 300 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 301 {
 302         return selinux_inode(inode);
 303 }
 304
 305 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 306 {
 307         int error;
 308
 309         error = __inode_security_revalidate(inode, NULL, !rcu);
 310         if (error)
 311                 return ERR_PTR(error);
 312         return selinux_inode(inode);
 313 }
 314
 315 /*
 316  * Get the security label of an inode.
 317  */
 318 static struct inode_security_struct *inode_security(struct inode *inode)
 319 {
 320         __inode_security_revalidate(inode, NULL, true);
 321         return selinux_inode(inode);
 322 }
 323
 324 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 325 {
 326         struct inode *inode = d_backing_inode(dentry);
 327
 328         return selinux_inode(inode);
 329 }
 330
 331 /*
 332  * Get the security label of a dentry's backing inode.
 333  */
 334 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 335 {
 336         struct inode *inode = d_backing_inode(dentry);
 337
 338         __inode_security_revalidate(inode, dentry, true);
 339         return selinux_inode(inode);
 340 }
 341
 342 static void inode_free_security(struct inode *inode)
 343 {
 344         struct inode_security_struct *isec = selinux_inode(inode);
 345         struct superblock_security_struct *sbsec;
 346
 347         if (!isec)
 348                 return;
 349         sbsec = selinux_superblock(inode->i_sb);
 350         /*
 351          * As not all inode security structures are in a list, we check for
 352          * empty list outside of the lock to make sure that we won't waste
 353          * time taking a lock doing nothing.
 354          *
 355          * The list_del_init() function can be safely called more than once.
 356          * It should not be possible for this function to be called with
 357          * concurrent list_add(), but for better safety against future changes
 358          * in the code, we use list_empty_careful() here.
 359          */
 360         if (!list_empty_careful(&isec->list)) {
 361                 spin_lock(&sbsec->isec_lock);
 362                 list_del_init(&isec->list);
 363                 spin_unlock(&sbsec->isec_lock);
 364         }
 365 }
 366
 367 struct selinux_mnt_opts {
 368         u32 fscontext_sid;
 369         u32 context_sid;
 370         u32 rootcontext_sid;
 371         u32 defcontext_sid;
 372 };
 373
 374 static void selinux_free_mnt_opts(void *mnt_opts)
 375 {
 376         kfree(mnt_opts);
 377 }
 378
 379 enum {
 380         Opt_error = -1,
 381         Opt_context = 0,
 382         Opt_defcontext = 1,
 383         Opt_fscontext = 2,
 384         Opt_rootcontext = 3,
 385         Opt_seclabel = 4,
 386 };
 387
 388 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 389 static const struct {
 390         const char *name;
 391         int len;
 392         int opt;
 393         bool has_arg;
 394 } tokens[] = {
 395         A(context, true),
 396         A(fscontext, true),
 397         A(defcontext, true),
 398         A(rootcontext, true),
 399         A(seclabel, false),
 400 };
 401 #undef A
 402
 403 static int match_opt_prefix(char *s, int l, char **arg)
 404 {
 405         int i;
 406
 407         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 408                 size_t len = tokens[i].len;
 409                 if (len > l || memcmp(s, tokens[i].name, len))
 410                         continue;
 411                 if (tokens[i].has_arg) {
 412                         if (len == l || s[len] != '=')
 413                                 continue;
 414                         *arg = s + len + 1;
 415                 } else if (len != l)
 416                         continue;
 417                 return tokens[i].opt;
 418         }
 419         return Opt_error;
 420 }
 421
 422 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 423
 424 static int may_context_mount_sb_relabel(u32 sid,
 425                         struct superblock_security_struct *sbsec,
 426                         const struct cred *cred)
 427 {
 428         const struct task_security_struct *tsec = selinux_cred(cred);
 429         int rc;
 430
 431         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 432                           FILESYSTEM__RELABELFROM, NULL);
 433         if (rc)
 434                 return rc;
 435
 436         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 437                           FILESYSTEM__RELABELTO, NULL);
 438         return rc;
 439 }
 440
 441 static int may_context_mount_inode_relabel(u32 sid,
 442                         struct superblock_security_struct *sbsec,
 443                         const struct cred *cred)
 444 {
 445         const struct task_security_struct *tsec = selinux_cred(cred);
 446         int rc;
 447         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 448                           FILESYSTEM__RELABELFROM, NULL);
 449         if (rc)
 450                 return rc;
 451
 452         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 453                           FILESYSTEM__ASSOCIATE, NULL);
 454         return rc;
 455 }
 456
 457 static int selinux_is_genfs_special_handling(struct super_block *sb)
 458 {
 459         /* Special handling. Genfs but also in-core setxattr handler */
 460         return  !strcmp(sb->s_type->name, "sysfs") ||
 461                 !strcmp(sb->s_type->name, "pstore") ||
 462                 !strcmp(sb->s_type->name, "debugfs") ||
 463                 !strcmp(sb->s_type->name, "tracefs") ||
 464                 !strcmp(sb->s_type->name, "rootfs") ||
 465                 (selinux_policycap_cgroupseclabel() &&
 466                  (!strcmp(sb->s_type->name, "cgroup") ||
 467                   !strcmp(sb->s_type->name, "cgroup2")));
 468 }
 469
 470 static int selinux_is_sblabel_mnt(struct super_block *sb)
 471 {
 472         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 473
 474         /*
 475          * IMPORTANT: Double-check logic in this function when adding a new
 476          * SECURITY_FS_USE_* definition!
 477          */
 478         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 479
 480         switch (sbsec->behavior) {
 481         case SECURITY_FS_USE_XATTR:
 482         case SECURITY_FS_USE_TRANS:
 483         case SECURITY_FS_USE_TASK:
 484         case SECURITY_FS_USE_NATIVE:
 485                 return 1;
 486
 487         case SECURITY_FS_USE_GENFS:
 488                 return selinux_is_genfs_special_handling(sb);
 489
 490         /* Never allow relabeling on context mounts */
 491         case SECURITY_FS_USE_MNTPOINT:
 492         case SECURITY_FS_USE_NONE:
 493         default:
 494                 return 0;
 495         }
 496 }
 497
 498 static int sb_check_xattr_support(struct super_block *sb)
 499 {
 500         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 501         struct dentry *root = sb->s_root;
 502         struct inode *root_inode = d_backing_inode(root);
 503         u32 sid;
 504         int rc;
 505
 506         /*
 507          * Make sure that the xattr handler exists and that no
 508          * error other than -ENODATA is returned by getxattr on
 509          * the root directory.  -ENODATA is ok, as this may be
 510          * the first boot of the SELinux kernel before we have
 511          * assigned xattr values to the filesystem.
 512          */
 513         if (!(root_inode->i_opflags & IOP_XATTR)) {
 514                 pr_warn("SELinux: (dev %s, type %s) has no xattr support\n",
 515                         sb->s_id, sb->s_type->name);
 516                 goto fallback;
 517         }
 518
 519         rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 520         if (rc < 0 && rc != -ENODATA) {
 521                 if (rc == -EOPNOTSUPP) {
 522                         pr_warn("SELinux: (dev %s, type %s) has no security xattr handler\n",
 523                                 sb->s_id, sb->s_type->name);
 524                         goto fallback;
 525                 } else {
 526                         pr_warn("SELinux: (dev %s, type %s) getxattr errno %d\n",
 527                                 sb->s_id, sb->s_type->name, -rc);
 528                         return rc;
 529                 }
 530         }
 531         return 0;
 532
 533 fallback:
 534         /* No xattr support - try to fallback to genfs if possible. */
 535         rc = security_genfs_sid(sb->s_type->name, "/",
 536                                 SECCLASS_DIR, &sid);
 537         if (rc)
 538                 return -EOPNOTSUPP;
 539
 540         pr_warn("SELinux: (dev %s, type %s) falling back to genfs\n",
 541                 sb->s_id, sb->s_type->name);
 542         sbsec->behavior = SECURITY_FS_USE_GENFS;
 543         sbsec->sid = sid;
 544         return 0;
 545 }
 546
 547 static int sb_finish_set_opts(struct super_block *sb)
 548 {
 549         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 550         struct dentry *root = sb->s_root;
 551         struct inode *root_inode = d_backing_inode(root);
 552         int rc = 0;
 553
 554         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 555                 rc = sb_check_xattr_support(sb);
 556                 if (rc)
 557                         return rc;
 558         }
 559
 560         sbsec->flags |= SE_SBINITIALIZED;
 561
 562         /*
 563          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 564          * leave the flag untouched because sb_clone_mnt_opts might be handing
 565          * us a superblock that needs the flag to be cleared.
 566          */
 567         if (selinux_is_sblabel_mnt(sb))
 568                 sbsec->flags |= SBLABEL_MNT;
 569         else
 570                 sbsec->flags &= ~SBLABEL_MNT;
 571
 572         /* Initialize the root inode. */
 573         rc = inode_doinit_with_dentry(root_inode, root);
 574
 575         /* Initialize any other inodes associated with the superblock, e.g.
 576            inodes created prior to initial policy load or inodes created
 577            during get_sb by a pseudo filesystem that directly
 578            populates itself. */
 579         spin_lock(&sbsec->isec_lock);
 580         while (!list_empty(&sbsec->isec_head)) {
 581                 struct inode_security_struct *isec =
 582                                 list_first_entry(&sbsec->isec_head,
 583                                            struct inode_security_struct, list);
 584                 struct inode *inode = isec->inode;
 585                 list_del_init(&isec->list);
 586                 spin_unlock(&sbsec->isec_lock);
 587                 inode = igrab(inode);
 588                 if (inode) {
 589                         if (!IS_PRIVATE(inode))
 590                                 inode_doinit_with_dentry(inode, NULL);
 591                         iput(inode);
 592                 }
 593                 spin_lock(&sbsec->isec_lock);
 594         }
 595         spin_unlock(&sbsec->isec_lock);
 596         return rc;
 597 }
 598
 599 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 600                       u32 old_sid, u32 new_sid)
 601 {
 602         char mnt_flags = sbsec->flags & SE_MNTMASK;
 603
 604         /* check if the old mount command had the same options */
 605         if (sbsec->flags & SE_SBINITIALIZED)
 606                 if (!(sbsec->flags & flag) ||
 607                     (old_sid != new_sid))
 608                         return 1;
 609
 610         /* check if we were passed the same options twice,
 611          * aka someone passed context=a,context=b
 612          */
 613         if (!(sbsec->flags & SE_SBINITIALIZED))
 614                 if (mnt_flags & flag)
 615                         return 1;
 616         return 0;
 617 }
 618
 619 /*
 620  * Allow filesystems with binary mount data to explicitly set mount point
 621  * labeling information.
 622  */
 623 static int selinux_set_mnt_opts(struct super_block *sb,
 624                                 void *mnt_opts,
 625                                 unsigned long kern_flags,
 626                                 unsigned long *set_kern_flags)
 627 {
 628         const struct cred *cred = current_cred();
 629         struct superblock_security_struct *sbsec = selinux_superblock(sb);
 630         struct dentry *root = sb->s_root;
 631         struct selinux_mnt_opts *opts = mnt_opts;
 632         struct inode_security_struct *root_isec;
 633         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 634         u32 defcontext_sid = 0;
 635         int rc = 0;
 636
 637         /*
 638          * Specifying internal flags without providing a place to
 639          * place the results is not allowed
 640          */
 641         if (kern_flags && !set_kern_flags)
 642                 return -EINVAL;
 643
 644         mutex_lock(&sbsec->lock);
 645
 646         if (!selinux_initialized()) {
 647                 if (!opts) {
 648                         /* Defer initialization until selinux_complete_init,
 649                            after the initial policy is loaded and the security
 650                            server is ready to handle calls. */
 651                         if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 652                                 sbsec->flags |= SE_SBNATIVE;
 653                                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 654                         }
 655                         goto out;
 656                 }
 657                 rc = -EINVAL;
 658                 pr_warn("SELinux: Unable to set superblock options "
 659                         "before the security server is initialized\n");
 660                 goto out;
 661         }
 662
 663         /*
 664          * Binary mount data FS will come through this function twice.  Once
 665          * from an explicit call and once from the generic calls from the vfs.
 666          * Since the generic VFS calls will not contain any security mount data
 667          * we need to skip the double mount verification.
 668          *
 669          * This does open a hole in which we will not notice if the first
 670          * mount using this sb set explicit options and a second mount using
 671          * this sb does not set any security options.  (The first options
 672          * will be used for both mounts)
 673          */
 674         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 675             && !opts)
 676                 goto out;
 677
 678         root_isec = backing_inode_security_novalidate(root);
 679
 680         /*
 681          * parse the mount options, check if they are valid sids.
 682          * also check if someone is trying to mount the same sb more
 683          * than once with different security options.
 684          */
 685         if (opts) {
 686                 if (opts->fscontext_sid) {
 687                         fscontext_sid = opts->fscontext_sid;
 688                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 689                                         fscontext_sid))
 690                                 goto out_double_mount;
 691                         sbsec->flags |= FSCONTEXT_MNT;
 692                 }
 693                 if (opts->context_sid) {
 694                         context_sid = opts->context_sid;
 695                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 696                                         context_sid))
 697                                 goto out_double_mount;
 698                         sbsec->flags |= CONTEXT_MNT;
 699                 }
 700                 if (opts->rootcontext_sid) {
 701                         rootcontext_sid = opts->rootcontext_sid;
 702                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 703                                         rootcontext_sid))
 704                                 goto out_double_mount;
 705                         sbsec->flags |= ROOTCONTEXT_MNT;
 706                 }
 707                 if (opts->defcontext_sid) {
 708                         defcontext_sid = opts->defcontext_sid;
 709                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 710                                         defcontext_sid))
 711                                 goto out_double_mount;
 712                         sbsec->flags |= DEFCONTEXT_MNT;
 713                 }
 714         }
 715
 716         if (sbsec->flags & SE_SBINITIALIZED) {
 717                 /* previously mounted with options, but not on this attempt? */
 718                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 719                         goto out_double_mount;
 720                 rc = 0;
 721                 goto out;
 722         }
 723
 724         if (strcmp(sb->s_type->name, "proc") == 0)
 725                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 726
 727         if (!strcmp(sb->s_type->name, "debugfs") ||
 728             !strcmp(sb->s_type->name, "tracefs") ||
 729             !strcmp(sb->s_type->name, "binder") ||
 730             !strcmp(sb->s_type->name, "bpf") ||
 731             !strcmp(sb->s_type->name, "pstore") ||
 732             !strcmp(sb->s_type->name, "securityfs"))
 733                 sbsec->flags |= SE_SBGENFS;
 734
 735         if (!strcmp(sb->s_type->name, "sysfs") ||
 736             !strcmp(sb->s_type->name, "cgroup") ||
 737             !strcmp(sb->s_type->name, "cgroup2"))
 738                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 739
 740         if (!sbsec->behavior) {
 741                 /*
 742                  * Determine the labeling behavior to use for this
 743                  * filesystem type.
 744                  */
 745                 rc = security_fs_use(sb);
 746                 if (rc) {
 747                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 748                                         __func__, sb->s_type->name, rc);
 749                         goto out;
 750                 }
 751         }
 752
 753         /*
 754          * If this is a user namespace mount and the filesystem type is not
 755          * explicitly whitelisted, then no contexts are allowed on the command
 756          * line and security labels must be ignored.
 757          */
 758         if (sb->s_user_ns != &init_user_ns &&
 759             strcmp(sb->s_type->name, "tmpfs") &&
 760             strcmp(sb->s_type->name, "ramfs") &&
 761             strcmp(sb->s_type->name, "devpts") &&
 762             strcmp(sb->s_type->name, "overlay")) {
 763                 if (context_sid || fscontext_sid || rootcontext_sid ||
 764                     defcontext_sid) {
 765                         rc = -EACCES;
 766                         goto out;
 767                 }
 768                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 769                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 770                         rc = security_transition_sid(current_sid(),
 771                                                      current_sid(),
 772                                                      SECCLASS_FILE, NULL,
 773                                                      &sbsec->mntpoint_sid);
 774                         if (rc)
 775                                 goto out;
 776                 }
 777                 goto out_set_opts;
 778         }
 779
 780         /* sets the context of the superblock for the fs being mounted. */
 781         if (fscontext_sid) {
 782                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 783                 if (rc)
 784                         goto out;
 785
 786                 sbsec->sid = fscontext_sid;
 787         }
 788
 789         /*
 790          * Switch to using mount point labeling behavior.
 791          * sets the label used on all file below the mountpoint, and will set
 792          * the superblock context if not already set.
 793          */
 794         if (sbsec->flags & SE_SBNATIVE) {
 795                 /*
 796                  * This means we are initializing a superblock that has been
 797                  * mounted before the SELinux was initialized and the
 798                  * filesystem requested native labeling. We had already
 799                  * returned SECURITY_LSM_NATIVE_LABELS in *set_kern_flags
 800                  * in the original mount attempt, so now we just need to set
 801                  * the SECURITY_FS_USE_NATIVE behavior.
 802                  */
 803                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 804         } else if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 805                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 806                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 807         }
 808
 809         if (context_sid) {
 810                 if (!fscontext_sid) {
 811                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 812                                                           cred);
 813                         if (rc)
 814                                 goto out;
 815                         sbsec->sid = context_sid;
 816                 } else {
 817                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 818                                                              cred);
 819                         if (rc)
 820                                 goto out;
 821                 }
 822                 if (!rootcontext_sid)
 823                         rootcontext_sid = context_sid;
 824
 825                 sbsec->mntpoint_sid = context_sid;
 826                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 827         }
 828
 829         if (rootcontext_sid) {
 830                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 831                                                      cred);
 832                 if (rc)
 833                         goto out;
 834
 835                 root_isec->sid = rootcontext_sid;
 836                 root_isec->initialized = LABEL_INITIALIZED;
 837         }
 838
 839         if (defcontext_sid) {
 840                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 841                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 842                         rc = -EINVAL;
 843                         pr_warn("SELinux: defcontext option is "
 844                                "invalid for this filesystem type\n");
 845                         goto out;
 846                 }
 847
 848                 if (defcontext_sid != sbsec->def_sid) {
 849                         rc = may_context_mount_inode_relabel(defcontext_sid,
 850                                                              sbsec, cred);
 851                         if (rc)
 852                                 goto out;
 853                 }
 854
 855                 sbsec->def_sid = defcontext_sid;
 856         }
 857
 858 out_set_opts:
 859         rc = sb_finish_set_opts(sb);
 860 out:
 861         mutex_unlock(&sbsec->lock);
 862         return rc;
 863 out_double_mount:
 864         rc = -EINVAL;
 865         pr_warn("SELinux: mount invalid.  Same superblock, different "
 866                "security settings for (dev %s, type %s)\n", sb->s_id,
 867                sb->s_type->name);
 868         goto out;
 869 }
 870
 871 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 872                                     const struct super_block *newsb)
 873 {
 874         struct superblock_security_struct *old = selinux_superblock(oldsb);
 875         struct superblock_security_struct *new = selinux_superblock(newsb);
 876         char oldflags = old->flags & SE_MNTMASK;
 877         char newflags = new->flags & SE_MNTMASK;
 878
 879         if (oldflags != newflags)
 880                 goto mismatch;
 881         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 882                 goto mismatch;
 883         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 884                 goto mismatch;
 885         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 886                 goto mismatch;
 887         if (oldflags & ROOTCONTEXT_MNT) {
 888                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 889                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 890                 if (oldroot->sid != newroot->sid)
 891                         goto mismatch;
 892         }
 893         return 0;
 894 mismatch:
 895         pr_warn("SELinux: mount invalid.  Same superblock, "
 896                             "different security settings for (dev %s, "
 897                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 898         return -EBUSY;
 899 }
 900
 901 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 902                                         struct super_block *newsb,
 903                                         unsigned long kern_flags,
 904                                         unsigned long *set_kern_flags)
 905 {
 906         int rc = 0;
 907         const struct superblock_security_struct *oldsbsec =
 908                                                 selinux_superblock(oldsb);
 909         struct superblock_security_struct *newsbsec = selinux_superblock(newsb);
 910
 911         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 912         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 913         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 914
 915         /*
 916          * Specifying internal flags without providing a place to
 917          * place the results is not allowed.
 918          */
 919         if (kern_flags && !set_kern_flags)
 920                 return -EINVAL;
 921
 922         mutex_lock(&newsbsec->lock);
 923
 924         /*
 925          * if the parent was able to be mounted it clearly had no special lsm
 926          * mount options.  thus we can safely deal with this superblock later
 927          */
 928         if (!selinux_initialized()) {
 929                 if (kern_flags & SECURITY_LSM_NATIVE_LABELS) {
 930                         newsbsec->flags |= SE_SBNATIVE;
 931                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 932                 }
 933                 goto out;
 934         }
 935
 936         /* how can we clone if the old one wasn't set up?? */
 937         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 938
 939         /* if fs is reusing a sb, make sure that the contexts match */
 940         if (newsbsec->flags & SE_SBINITIALIZED) {
 941                 mutex_unlock(&newsbsec->lock);
 942                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 943                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 944                 return selinux_cmp_sb_context(oldsb, newsb);
 945         }
 946
 947         newsbsec->flags = oldsbsec->flags;
 948
 949         newsbsec->sid = oldsbsec->sid;
 950         newsbsec->def_sid = oldsbsec->def_sid;
 951         newsbsec->behavior = oldsbsec->behavior;
 952
 953         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 954                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 955                 rc = security_fs_use(newsb);
 956                 if (rc)
 957                         goto out;
 958         }
 959
 960         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 961                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 962                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 963         }
 964
 965         if (set_context) {
 966                 u32 sid = oldsbsec->mntpoint_sid;
 967
 968                 if (!set_fscontext)
 969                         newsbsec->sid = sid;
 970                 if (!set_rootcontext) {
 971                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 972                         newisec->sid = sid;
 973                 }
 974                 newsbsec->mntpoint_sid = sid;
 975         }
 976         if (set_rootcontext) {
 977                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 978                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 979
 980                 newisec->sid = oldisec->sid;
 981         }
 982
 983         sb_finish_set_opts(newsb);
 984 out:
 985         mutex_unlock(&newsbsec->lock);
 986         return rc;
 987 }
 988
 989 /*
 990  * NOTE: the caller is responsible for freeing the memory even if on error.
 991  */
 992 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 993 {
 994         struct selinux_mnt_opts *opts = *mnt_opts;
 995         u32 *dst_sid;
 996         int rc;
 997
 998         if (token == Opt_seclabel)
 999                 /* eaten and completely ignored */
1000                 return 0;
1001         if (!s)
1002                 return -EINVAL;
1003
1004         if (!selinux_initialized()) {
1005                 pr_warn("SELinux: Unable to set superblock options before the security server is initialized\n");
1006                 return -EINVAL;
1007         }
1008
1009         if (!opts) {
1010                 opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1011                 if (!opts)
1012                         return -ENOMEM;
1013                 *mnt_opts = opts;
1014         }
1015
1016         switch (token) {
1017         case Opt_context:
1018                 if (opts->context_sid || opts->defcontext_sid)
1019                         goto err;
1020                 dst_sid = &opts->context_sid;
1021                 break;
1022         case Opt_fscontext:
1023                 if (opts->fscontext_sid)
1024                         goto err;
1025                 dst_sid = &opts->fscontext_sid;
1026                 break;
1027         case Opt_rootcontext:
1028                 if (opts->rootcontext_sid)
1029                         goto err;
1030                 dst_sid = &opts->rootcontext_sid;
1031                 break;
1032         case Opt_defcontext:
1033                 if (opts->context_sid || opts->defcontext_sid)
1034                         goto err;
1035                 dst_sid = &opts->defcontext_sid;
1036                 break;
1037         default:
1038                 WARN_ON(1);
1039                 return -EINVAL;
1040         }
1041         rc = security_context_str_to_sid(s, dst_sid, GFP_KERNEL);
1042         if (rc)
1043                 pr_warn("SELinux: security_context_str_to_sid (%s) failed with errno=%d\n",
1044                         s, rc);
1045         return rc;
1046
1047 err:
1048         pr_warn(SEL_MOUNT_FAIL_MSG);
1049         return -EINVAL;
1050 }
1051
1052 static int show_sid(struct seq_file *m, u32 sid)
1053 {
1054         char *context = NULL;
1055         u32 len;
1056         int rc;
1057
1058         rc = security_sid_to_context(sid, &context, &len);
1059         if (!rc) {
1060                 bool has_comma = strchr(context, ',');
1061
1062                 seq_putc(m, '=');
1063                 if (has_comma)
1064                         seq_putc(m, '\"');
1065                 seq_escape(m, context, "\"\n\\");
1066                 if (has_comma)
1067                         seq_putc(m, '\"');
1068         }
1069         kfree(context);
1070         return rc;
1071 }
1072
1073 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1074 {
1075         struct superblock_security_struct *sbsec = selinux_superblock(sb);
1076         int rc;
1077
1078         if (!(sbsec->flags & SE_SBINITIALIZED))
1079                 return 0;
1080
1081         if (!selinux_initialized())
1082                 return 0;
1083
1084         if (sbsec->flags & FSCONTEXT_MNT) {
1085                 seq_putc(m, ',');
1086                 seq_puts(m, FSCONTEXT_STR);
1087                 rc = show_sid(m, sbsec->sid);
1088                 if (rc)
1089                         return rc;
1090         }
1091         if (sbsec->flags & CONTEXT_MNT) {
1092                 seq_putc(m, ',');
1093                 seq_puts(m, CONTEXT_STR);
1094                 rc = show_sid(m, sbsec->mntpoint_sid);
1095                 if (rc)
1096                         return rc;
1097         }
1098         if (sbsec->flags & DEFCONTEXT_MNT) {
1099                 seq_putc(m, ',');
1100                 seq_puts(m, DEFCONTEXT_STR);
1101                 rc = show_sid(m, sbsec->def_sid);
1102                 if (rc)
1103                         return rc;
1104         }
1105         if (sbsec->flags & ROOTCONTEXT_MNT) {
1106                 struct dentry *root = sb->s_root;
1107                 struct inode_security_struct *isec = backing_inode_security(root);
1108                 seq_putc(m, ',');
1109                 seq_puts(m, ROOTCONTEXT_STR);
1110                 rc = show_sid(m, isec->sid);
1111                 if (rc)
1112                         return rc;
1113         }
1114         if (sbsec->flags & SBLABEL_MNT) {
1115                 seq_putc(m, ',');
1116                 seq_puts(m, SECLABEL_STR);
1117         }
1118         return 0;
1119 }
1120
1121 static inline u16 inode_mode_to_security_class(umode_t mode)
1122 {
1123         switch (mode & S_IFMT) {
1124         case S_IFSOCK:
1125                 return SECCLASS_SOCK_FILE;
1126         case S_IFLNK:
1127                 return SECCLASS_LNK_FILE;
1128         case S_IFREG:
1129                 return SECCLASS_FILE;
1130         case S_IFBLK:
1131                 return SECCLASS_BLK_FILE;
1132         case S_IFDIR:
1133                 return SECCLASS_DIR;
1134         case S_IFCHR:
1135                 return SECCLASS_CHR_FILE;
1136         case S_IFIFO:
1137                 return SECCLASS_FIFO_FILE;
1138
1139         }
1140
1141         return SECCLASS_FILE;
1142 }
1143
1144 static inline int default_protocol_stream(int protocol)
1145 {
1146         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP ||
1147                 protocol == IPPROTO_MPTCP);
1148 }
1149
1150 static inline int default_protocol_dgram(int protocol)
1151 {
1152         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1153 }
1154
1155 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1156 {
1157         bool extsockclass = selinux_policycap_extsockclass();
1158
1159         switch (family) {
1160         case PF_UNIX:
1161                 switch (type) {
1162                 case SOCK_STREAM:
1163                 case SOCK_SEQPACKET:
1164                         return SECCLASS_UNIX_STREAM_SOCKET;
1165                 case SOCK_DGRAM:
1166                 case SOCK_RAW:
1167                         return SECCLASS_UNIX_DGRAM_SOCKET;
1168                 }
1169                 break;
1170         case PF_INET:
1171         case PF_INET6:
1172                 switch (type) {
1173                 case SOCK_STREAM:
1174                 case SOCK_SEQPACKET:
1175                         if (default_protocol_stream(protocol))
1176                                 return SECCLASS_TCP_SOCKET;
1177                         else if (extsockclass && protocol == IPPROTO_SCTP)
1178                                 return SECCLASS_SCTP_SOCKET;
1179                         else
1180                                 return SECCLASS_RAWIP_SOCKET;
1181                 case SOCK_DGRAM:
1182                         if (default_protocol_dgram(protocol))
1183                                 return SECCLASS_UDP_SOCKET;
1184                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1185                                                   protocol == IPPROTO_ICMPV6))
1186                                 return SECCLASS_ICMP_SOCKET;
1187                         else
1188                                 return SECCLASS_RAWIP_SOCKET;
1189                 case SOCK_DCCP:
1190                         return SECCLASS_DCCP_SOCKET;
1191                 default:
1192                         return SECCLASS_RAWIP_SOCKET;
1193                 }
1194                 break;
1195         case PF_NETLINK:
1196                 switch (protocol) {
1197                 case NETLINK_ROUTE:
1198                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1199                 case NETLINK_SOCK_DIAG:
1200                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1201                 case NETLINK_NFLOG:
1202                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1203                 case NETLINK_XFRM:
1204                         return SECCLASS_NETLINK_XFRM_SOCKET;
1205                 case NETLINK_SELINUX:
1206                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1207                 case NETLINK_ISCSI:
1208                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1209                 case NETLINK_AUDIT:
1210                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1211                 case NETLINK_FIB_LOOKUP:
1212                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1213                 case NETLINK_CONNECTOR:
1214                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1215                 case NETLINK_NETFILTER:
1216                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1217                 case NETLINK_DNRTMSG:
1218                         return SECCLASS_NETLINK_DNRT_SOCKET;
1219                 case NETLINK_KOBJECT_UEVENT:
1220                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1221                 case NETLINK_GENERIC:
1222                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1223                 case NETLINK_SCSITRANSPORT:
1224                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1225                 case NETLINK_RDMA:
1226                         return SECCLASS_NETLINK_RDMA_SOCKET;
1227                 case NETLINK_CRYPTO:
1228                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1229                 default:
1230                         return SECCLASS_NETLINK_SOCKET;
1231                 }
1232         case PF_PACKET:
1233                 return SECCLASS_PACKET_SOCKET;
1234         case PF_KEY:
1235                 return SECCLASS_KEY_SOCKET;
1236         case PF_APPLETALK:
1237                 return SECCLASS_APPLETALK_SOCKET;
1238         }
1239
1240         if (extsockclass) {
1241                 switch (family) {
1242                 case PF_AX25:
1243                         return SECCLASS_AX25_SOCKET;
1244                 case PF_IPX:
1245                         return SECCLASS_IPX_SOCKET;
1246                 case PF_NETROM:
1247                         return SECCLASS_NETROM_SOCKET;
1248                 case PF_ATMPVC:
1249                         return SECCLASS_ATMPVC_SOCKET;
1250                 case PF_X25:
1251                         return SECCLASS_X25_SOCKET;
1252                 case PF_ROSE:
1253                         return SECCLASS_ROSE_SOCKET;
1254                 case PF_DECnet:
1255                         return SECCLASS_DECNET_SOCKET;
1256                 case PF_ATMSVC:
1257                         return SECCLASS_ATMSVC_SOCKET;
1258                 case PF_RDS:
1259                         return SECCLASS_RDS_SOCKET;
1260                 case PF_IRDA:
1261                         return SECCLASS_IRDA_SOCKET;
1262                 case PF_PPPOX:
1263                         return SECCLASS_PPPOX_SOCKET;
1264                 case PF_LLC:
1265                         return SECCLASS_LLC_SOCKET;
1266                 case PF_CAN:
1267                         return SECCLASS_CAN_SOCKET;
1268                 case PF_TIPC:
1269                         return SECCLASS_TIPC_SOCKET;
1270                 case PF_BLUETOOTH:
1271                         return SECCLASS_BLUETOOTH_SOCKET;
1272                 case PF_IUCV:
1273                         return SECCLASS_IUCV_SOCKET;
1274                 case PF_RXRPC:
1275                         return SECCLASS_RXRPC_SOCKET;
1276                 case PF_ISDN:
1277                         return SECCLASS_ISDN_SOCKET;
1278                 case PF_PHONET:
1279                         return SECCLASS_PHONET_SOCKET;
1280                 case PF_IEEE802154:
1281                         return SECCLASS_IEEE802154_SOCKET;
1282                 case PF_CAIF:
1283                         return SECCLASS_CAIF_SOCKET;
1284                 case PF_ALG:
1285                         return SECCLASS_ALG_SOCKET;
1286                 case PF_NFC:
1287                         return SECCLASS_NFC_SOCKET;
1288                 case PF_VSOCK:
1289                         return SECCLASS_VSOCK_SOCKET;
1290                 case PF_KCM:
1291                         return SECCLASS_KCM_SOCKET;
1292                 case PF_QIPCRTR:
1293                         return SECCLASS_QIPCRTR_SOCKET;
1294                 case PF_SMC:
1295                         return SECCLASS_SMC_SOCKET;
1296                 case PF_XDP:
1297                         return SECCLASS_XDP_SOCKET;
1298                 case PF_MCTP:
1299                         return SECCLASS_MCTP_SOCKET;
1300 #if PF_MAX > 46
1301 #error New address family defined, please update this function.
1302 #endif
1303                 }
1304         }
1305
1306         return SECCLASS_SOCKET;
1307 }
1308
1309 static int selinux_genfs_get_sid(struct dentry *dentry,
1310                                  u16 tclass,
1311                                  u16 flags,
1312                                  u32 *sid)
1313 {
1314         int rc;
1315         struct super_block *sb = dentry->d_sb;
1316         char *buffer, *path;
1317
1318         buffer = (char *)__get_free_page(GFP_KERNEL);
1319         if (!buffer)
1320                 return -ENOMEM;
1321
1322         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1323         if (IS_ERR(path))
1324                 rc = PTR_ERR(path);
1325         else {
1326                 if (flags & SE_SBPROC) {
1327                         /* each process gets a /proc/PID/ entry. Strip off the
1328                          * PID part to get a valid selinux labeling.
1329                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1330                         while (path[1] >= '0' && path[1] <= '9') {
1331                                 path[1] = '/';
1332                                 path++;
1333                         }
1334                 }
1335                 rc = security_genfs_sid(sb->s_type->name,
1336                                         path, tclass, sid);
1337                 if (rc == -ENOENT) {
1338                         /* No match in policy, mark as unlabeled. */
1339                         *sid = SECINITSID_UNLABELED;
1340                         rc = 0;
1341                 }
1342         }
1343         free_page((unsigned long)buffer);
1344         return rc;
1345 }
1346
1347 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1348                                   u32 def_sid, u32 *sid)
1349 {
1350 #define INITCONTEXTLEN 255
1351         char *context;
1352         unsigned int len;
1353         int rc;
1354
1355         len = INITCONTEXTLEN;
1356         context = kmalloc(len + 1, GFP_NOFS);
1357         if (!context)
1358                 return -ENOMEM;
1359
1360         context[len] = '\0';
1361         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1362         if (rc == -ERANGE) {
1363                 kfree(context);
1364
1365                 /* Need a larger buffer.  Query for the right size. */
1366                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1367                 if (rc < 0)
1368                         return rc;
1369
1370                 len = rc;
1371                 context = kmalloc(len + 1, GFP_NOFS);
1372                 if (!context)
1373                         return -ENOMEM;
1374
1375                 context[len] = '\0';
1376                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1377                                     context, len);
1378         }
1379         if (rc < 0) {
1380                 kfree(context);
1381                 if (rc != -ENODATA) {
1382                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1383                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1384                         return rc;
1385                 }
1386                 *sid = def_sid;
1387                 return 0;
1388         }
1389
1390         rc = security_context_to_sid_default(context, rc, sid,
1391                                              def_sid, GFP_NOFS);
1392         if (rc) {
1393                 char *dev = inode->i_sb->s_id;
1394                 unsigned long ino = inode->i_ino;
1395
1396                 if (rc == -EINVAL) {
1397                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1398                                               ino, dev, context);
1399                 } else {
1400                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1401                                 __func__, context, -rc, dev, ino);
1402                 }
1403         }
1404         kfree(context);
1405         return 0;
1406 }
1407
1408 /* The inode's security attributes must be initialized before first use. */
1409 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1410 {
1411         struct superblock_security_struct *sbsec = NULL;
1412         struct inode_security_struct *isec = selinux_inode(inode);
1413         u32 task_sid, sid = 0;
1414         u16 sclass;
1415         struct dentry *dentry;
1416         int rc = 0;
1417
1418         if (isec->initialized == LABEL_INITIALIZED)
1419                 return 0;
1420
1421         spin_lock(&isec->lock);
1422         if (isec->initialized == LABEL_INITIALIZED)
1423                 goto out_unlock;
1424
1425         if (isec->sclass == SECCLASS_FILE)
1426                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1427
1428         sbsec = selinux_superblock(inode->i_sb);
1429         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1430                 /* Defer initialization until selinux_complete_init,
1431                    after the initial policy is loaded and the security
1432                    server is ready to handle calls. */
1433                 spin_lock(&sbsec->isec_lock);
1434                 if (list_empty(&isec->list))
1435                         list_add(&isec->list, &sbsec->isec_head);
1436                 spin_unlock(&sbsec->isec_lock);
1437                 goto out_unlock;
1438         }
1439
1440         sclass = isec->sclass;
1441         task_sid = isec->task_sid;
1442         sid = isec->sid;
1443         isec->initialized = LABEL_PENDING;
1444         spin_unlock(&isec->lock);
1445
1446         switch (sbsec->behavior) {
1447         /*
1448          * In case of SECURITY_FS_USE_NATIVE we need to re-fetch the labels
1449          * via xattr when called from delayed_superblock_init().
1450          */
1451         case SECURITY_FS_USE_NATIVE:
1452         case SECURITY_FS_USE_XATTR:
1453                 if (!(inode->i_opflags & IOP_XATTR)) {
1454                         sid = sbsec->def_sid;
1455                         break;
1456                 }
1457                 /* Need a dentry, since the xattr API requires one.
1458                    Life would be simpler if we could just pass the inode. */
1459                 if (opt_dentry) {
1460                         /* Called from d_instantiate or d_splice_alias. */
1461                         dentry = dget(opt_dentry);
1462                 } else {
1463                         /*
1464                          * Called from selinux_complete_init, try to find a dentry.
1465                          * Some filesystems really want a connected one, so try
1466                          * that first.  We could split SECURITY_FS_USE_XATTR in
1467                          * two, depending upon that...
1468                          */
1469                         dentry = d_find_alias(inode);
1470                         if (!dentry)
1471                                 dentry = d_find_any_alias(inode);
1472                 }
1473                 if (!dentry) {
1474                         /*
1475                          * this is can be hit on boot when a file is accessed
1476                          * before the policy is loaded.  When we load policy we
1477                          * may find inodes that have no dentry on the
1478                          * sbsec->isec_head list.  No reason to complain as these
1479                          * will get fixed up the next time we go through
1480                          * inode_doinit with a dentry, before these inodes could
1481                          * be used again by userspace.
1482                          */
1483                         goto out_invalid;
1484                 }
1485
1486                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1487                                             &sid);
1488                 dput(dentry);
1489                 if (rc)
1490                         goto out;
1491                 break;
1492         case SECURITY_FS_USE_TASK:
1493                 sid = task_sid;
1494                 break;
1495         case SECURITY_FS_USE_TRANS:
1496                 /* Default to the fs SID. */
1497                 sid = sbsec->sid;
1498
1499                 /* Try to obtain a transition SID. */
1500                 rc = security_transition_sid(task_sid, sid,
1501                                              sclass, NULL, &sid);
1502                 if (rc)
1503                         goto out;
1504                 break;
1505         case SECURITY_FS_USE_MNTPOINT:
1506                 sid = sbsec->mntpoint_sid;
1507                 break;
1508         default:
1509                 /* Default to the fs superblock SID. */
1510                 sid = sbsec->sid;
1511
1512                 if ((sbsec->flags & SE_SBGENFS) &&
1513                      (!S_ISLNK(inode->i_mode) ||
1514                       selinux_policycap_genfs_seclabel_symlinks())) {
1515                         /* We must have a dentry to determine the label on
1516                          * procfs inodes */
1517                         if (opt_dentry) {
1518                                 /* Called from d_instantiate or
1519                                  * d_splice_alias. */
1520                                 dentry = dget(opt_dentry);
1521                         } else {
1522                                 /* Called from selinux_complete_init, try to
1523                                  * find a dentry.  Some filesystems really want
1524                                  * a connected one, so try that first.
1525                                  */
1526                                 dentry = d_find_alias(inode);
1527                                 if (!dentry)
1528                                         dentry = d_find_any_alias(inode);
1529                         }
1530                         /*
1531                          * This can be hit on boot when a file is accessed
1532                          * before the policy is loaded.  When we load policy we
1533                          * may find inodes that have no dentry on the
1534                          * sbsec->isec_head list.  No reason to complain as
1535                          * these will get fixed up the next time we go through
1536                          * inode_doinit() with a dentry, before these inodes
1537                          * could be used again by userspace.
1538                          */
1539                         if (!dentry)
1540                                 goto out_invalid;
1541                         rc = selinux_genfs_get_sid(dentry, sclass,
1542                                                    sbsec->flags, &sid);
1543                         if (rc) {
1544                                 dput(dentry);
1545                                 goto out;
1546                         }
1547
1548                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1549                             (inode->i_opflags & IOP_XATTR)) {
1550                                 rc = inode_doinit_use_xattr(inode, dentry,
1551                                                             sid, &sid);
1552                                 if (rc) {
1553                                         dput(dentry);
1554                                         goto out;
1555                                 }
1556                         }
1557                         dput(dentry);
1558                 }
1559                 break;
1560         }
1561
1562 out:
1563         spin_lock(&isec->lock);
1564         if (isec->initialized == LABEL_PENDING) {
1565                 if (rc) {
1566                         isec->initialized = LABEL_INVALID;
1567                         goto out_unlock;
1568                 }
1569                 isec->initialized = LABEL_INITIALIZED;
1570                 isec->sid = sid;
1571         }
1572
1573 out_unlock:
1574         spin_unlock(&isec->lock);
1575         return rc;
1576
1577 out_invalid:
1578         spin_lock(&isec->lock);
1579         if (isec->initialized == LABEL_PENDING) {
1580                 isec->initialized = LABEL_INVALID;
1581                 isec->sid = sid;
1582         }
1583         spin_unlock(&isec->lock);
1584         return 0;
1585 }
1586
1587 /* Convert a Linux signal to an access vector. */
1588 static inline u32 signal_to_av(int sig)
1589 {
1590         u32 perm = 0;
1591
1592         switch (sig) {
1593         case SIGCHLD:
1594                 /* Commonly granted from child to parent. */
1595                 perm = PROCESS__SIGCHLD;
1596                 break;
1597         case SIGKILL:
1598                 /* Cannot be caught or ignored */
1599                 perm = PROCESS__SIGKILL;
1600                 break;
1601         case SIGSTOP:
1602                 /* Cannot be caught or ignored */
1603                 perm = PROCESS__SIGSTOP;
1604                 break;
1605         default:
1606                 /* All other signals. */
1607                 perm = PROCESS__SIGNAL;
1608                 break;
1609         }
1610
1611         return perm;
1612 }
1613
1614 #if CAP_LAST_CAP > 63
1615 #error Fix SELinux to handle capabilities > 63.
1616 #endif
1617
1618 /* Check whether a task is allowed to use a capability. */
1619 static int cred_has_capability(const struct cred *cred,
1620                                int cap, unsigned int opts, bool initns)
1621 {
1622         struct common_audit_data ad;
1623         struct av_decision avd;
1624         u16 sclass;
1625         u32 sid = cred_sid(cred);
1626         u32 av = CAP_TO_MASK(cap);
1627         int rc;
1628
1629         ad.type = LSM_AUDIT_DATA_CAP;
1630         ad.u.cap = cap;
1631
1632         switch (CAP_TO_INDEX(cap)) {
1633         case 0:
1634                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1635                 break;
1636         case 1:
1637                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1638                 break;
1639         default:
1640                 pr_err("SELinux:  out of range capability %d\n", cap);
1641                 BUG();
1642                 return -EINVAL;
1643         }
1644
1645         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1646         if (!(opts & CAP_OPT_NOAUDIT)) {
1647                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1648                 if (rc2)
1649                         return rc2;
1650         }
1651         return rc;
1652 }
1653
1654 /* Check whether a task has a particular permission to an inode.
1655    The 'adp' parameter is optional and allows other audit
1656    data to be passed (e.g. the dentry). */
1657 static int inode_has_perm(const struct cred *cred,
1658                           struct inode *inode,
1659                           u32 perms,
1660                           struct common_audit_data *adp)
1661 {
1662         struct inode_security_struct *isec;
1663         u32 sid;
1664
1665         if (unlikely(IS_PRIVATE(inode)))
1666                 return 0;
1667
1668         sid = cred_sid(cred);
1669         isec = selinux_inode(inode);
1670
1671         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1672 }
1673
1674 /* Same as inode_has_perm, but pass explicit audit data containing
1675    the dentry to help the auditing code to more easily generate the
1676    pathname if needed. */
1677 static inline int dentry_has_perm(const struct cred *cred,
1678                                   struct dentry *dentry,
1679                                   u32 av)
1680 {
1681         struct inode *inode = d_backing_inode(dentry);
1682         struct common_audit_data ad;
1683
1684         ad.type = LSM_AUDIT_DATA_DENTRY;
1685         ad.u.dentry = dentry;
1686         __inode_security_revalidate(inode, dentry, true);
1687         return inode_has_perm(cred, inode, av, &ad);
1688 }
1689
1690 /* Same as inode_has_perm, but pass explicit audit data containing
1691    the path to help the auditing code to more easily generate the
1692    pathname if needed. */
1693 static inline int path_has_perm(const struct cred *cred,
1694                                 const struct path *path,
1695                                 u32 av)
1696 {
1697         struct inode *inode = d_backing_inode(path->dentry);
1698         struct common_audit_data ad;
1699
1700         ad.type = LSM_AUDIT_DATA_PATH;
1701         ad.u.path = *path;
1702         __inode_security_revalidate(inode, path->dentry, true);
1703         return inode_has_perm(cred, inode, av, &ad);
1704 }
1705
1706 /* Same as path_has_perm, but uses the inode from the file struct. */
1707 static inline int file_path_has_perm(const struct cred *cred,
1708                                      struct file *file,
1709                                      u32 av)
1710 {
1711         struct common_audit_data ad;
1712
1713         ad.type = LSM_AUDIT_DATA_FILE;
1714         ad.u.file = file;
1715         return inode_has_perm(cred, file_inode(file), av, &ad);
1716 }
1717
1718 #ifdef CONFIG_BPF_SYSCALL
1719 static int bpf_fd_pass(const struct file *file, u32 sid);
1720 #endif
1721
1722 /* Check whether a task can use an open file descriptor to
1723    access an inode in a given way.  Check access to the
1724    descriptor itself, and then use dentry_has_perm to
1725    check a particular permission to the file.
1726    Access to the descriptor is implicitly granted if it
1727    has the same SID as the process.  If av is zero, then
1728    access to the file is not checked, e.g. for cases
1729    where only the descriptor is affected like seek. */
1730 static int file_has_perm(const struct cred *cred,
1731                          struct file *file,
1732                          u32 av)
1733 {
1734         struct file_security_struct *fsec = selinux_file(file);
1735         struct inode *inode = file_inode(file);
1736         struct common_audit_data ad;
1737         u32 sid = cred_sid(cred);
1738         int rc;
1739
1740         ad.type = LSM_AUDIT_DATA_FILE;
1741         ad.u.file = file;
1742
1743         if (sid != fsec->sid) {
1744                 rc = avc_has_perm(sid, fsec->sid,
1745                                   SECCLASS_FD,
1746                                   FD__USE,
1747                                   &ad);
1748                 if (rc)
1749                         goto out;
1750         }
1751
1752 #ifdef CONFIG_BPF_SYSCALL
1753         rc = bpf_fd_pass(file, cred_sid(cred));
1754         if (rc)
1755                 return rc;
1756 #endif
1757
1758         /* av is zero if only checking access to the descriptor. */
1759         rc = 0;
1760         if (av)
1761                 rc = inode_has_perm(cred, inode, av, &ad);
1762
1763 out:
1764         return rc;
1765 }
1766
1767 /*
1768  * Determine the label for an inode that might be unioned.
1769  */
1770 static int
1771 selinux_determine_inode_label(const struct task_security_struct *tsec,
1772                                  struct inode *dir,
1773                                  const struct qstr *name, u16 tclass,
1774                                  u32 *_new_isid)
1775 {
1776         const struct superblock_security_struct *sbsec =
1777                                                 selinux_superblock(dir->i_sb);
1778
1779         if ((sbsec->flags & SE_SBINITIALIZED) &&
1780             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1781                 *_new_isid = sbsec->mntpoint_sid;
1782         } else if ((sbsec->flags & SBLABEL_MNT) &&
1783                    tsec->create_sid) {
1784                 *_new_isid = tsec->create_sid;
1785         } else {
1786                 const struct inode_security_struct *dsec = inode_security(dir);
1787                 return security_transition_sid(tsec->sid,
1788                                                dsec->sid, tclass,
1789                                                name, _new_isid);
1790         }
1791
1792         return 0;
1793 }
1794
1795 /* Check whether a task can create a file. */
1796 static int may_create(struct inode *dir,
1797                       struct dentry *dentry,
1798                       u16 tclass)
1799 {
1800         const struct task_security_struct *tsec = selinux_cred(current_cred());
1801         struct inode_security_struct *dsec;
1802         struct superblock_security_struct *sbsec;
1803         u32 sid, newsid;
1804         struct common_audit_data ad;
1805         int rc;
1806
1807         dsec = inode_security(dir);
1808         sbsec = selinux_superblock(dir->i_sb);
1809
1810         sid = tsec->sid;
1811
1812         ad.type = LSM_AUDIT_DATA_DENTRY;
1813         ad.u.dentry = dentry;
1814
1815         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1816                           DIR__ADD_NAME | DIR__SEARCH,
1817                           &ad);
1818         if (rc)
1819                 return rc;
1820
1821         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1822                                            &newsid);
1823         if (rc)
1824                 return rc;
1825
1826         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1827         if (rc)
1828                 return rc;
1829
1830         return avc_has_perm(newsid, sbsec->sid,
1831                             SECCLASS_FILESYSTEM,
1832                             FILESYSTEM__ASSOCIATE, &ad);
1833 }
1834
1835 #define MAY_LINK        0
1836 #define MAY_UNLINK      1
1837 #define MAY_RMDIR       2
1838
1839 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1840 static int may_link(struct inode *dir,
1841                     struct dentry *dentry,
1842                     int kind)
1843
1844 {
1845         struct inode_security_struct *dsec, *isec;
1846         struct common_audit_data ad;
1847         u32 sid = current_sid();
1848         u32 av;
1849         int rc;
1850
1851         dsec = inode_security(dir);
1852         isec = backing_inode_security(dentry);
1853
1854         ad.type = LSM_AUDIT_DATA_DENTRY;
1855         ad.u.dentry = dentry;
1856
1857         av = DIR__SEARCH;
1858         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1859         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1860         if (rc)
1861                 return rc;
1862
1863         switch (kind) {
1864         case MAY_LINK:
1865                 av = FILE__LINK;
1866                 break;
1867         case MAY_UNLINK:
1868                 av = FILE__UNLINK;
1869                 break;
1870         case MAY_RMDIR:
1871                 av = DIR__RMDIR;
1872                 break;
1873         default:
1874                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1875                         __func__, kind);
1876                 return 0;
1877         }
1878
1879         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1880         return rc;
1881 }
1882
1883 static inline int may_rename(struct inode *old_dir,
1884                              struct dentry *old_dentry,
1885                              struct inode *new_dir,
1886                              struct dentry *new_dentry)
1887 {
1888         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1889         struct common_audit_data ad;
1890         u32 sid = current_sid();
1891         u32 av;
1892         int old_is_dir, new_is_dir;
1893         int rc;
1894
1895         old_dsec = inode_security(old_dir);
1896         old_isec = backing_inode_security(old_dentry);
1897         old_is_dir = d_is_dir(old_dentry);
1898         new_dsec = inode_security(new_dir);
1899
1900         ad.type = LSM_AUDIT_DATA_DENTRY;
1901
1902         ad.u.dentry = old_dentry;
1903         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1904                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1905         if (rc)
1906                 return rc;
1907         rc = avc_has_perm(sid, old_isec->sid,
1908                           old_isec->sclass, FILE__RENAME, &ad);
1909         if (rc)
1910                 return rc;
1911         if (old_is_dir && new_dir != old_dir) {
1912                 rc = avc_has_perm(sid, old_isec->sid,
1913                                   old_isec->sclass, DIR__REPARENT, &ad);
1914                 if (rc)
1915                         return rc;
1916         }
1917
1918         ad.u.dentry = new_dentry;
1919         av = DIR__ADD_NAME | DIR__SEARCH;
1920         if (d_is_positive(new_dentry))
1921                 av |= DIR__REMOVE_NAME;
1922         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1923         if (rc)
1924                 return rc;
1925         if (d_is_positive(new_dentry)) {
1926                 new_isec = backing_inode_security(new_dentry);
1927                 new_is_dir = d_is_dir(new_dentry);
1928                 rc = avc_has_perm(sid, new_isec->sid,
1929                                   new_isec->sclass,
1930                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1931                 if (rc)
1932                         return rc;
1933         }
1934
1935         return 0;
1936 }
1937
1938 /* Check whether a task can perform a filesystem operation. */
1939 static int superblock_has_perm(const struct cred *cred,
1940                                const struct super_block *sb,
1941                                u32 perms,
1942                                struct common_audit_data *ad)
1943 {
1944         struct superblock_security_struct *sbsec;
1945         u32 sid = cred_sid(cred);
1946
1947         sbsec = selinux_superblock(sb);
1948         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1949 }
1950
1951 /* Convert a Linux mode and permission mask to an access vector. */
1952 static inline u32 file_mask_to_av(int mode, int mask)
1953 {
1954         u32 av = 0;
1955
1956         if (!S_ISDIR(mode)) {
1957                 if (mask & MAY_EXEC)
1958                         av |= FILE__EXECUTE;
1959                 if (mask & MAY_READ)
1960                         av |= FILE__READ;
1961
1962                 if (mask & MAY_APPEND)
1963                         av |= FILE__APPEND;
1964                 else if (mask & MAY_WRITE)
1965                         av |= FILE__WRITE;
1966
1967         } else {
1968                 if (mask & MAY_EXEC)
1969                         av |= DIR__SEARCH;
1970                 if (mask & MAY_WRITE)
1971                         av |= DIR__WRITE;
1972                 if (mask & MAY_READ)
1973                         av |= DIR__READ;
1974         }
1975
1976         return av;
1977 }
1978
1979 /* Convert a Linux file to an access vector. */
1980 static inline u32 file_to_av(const struct file *file)
1981 {
1982         u32 av = 0;
1983
1984         if (file->f_mode & FMODE_READ)
1985                 av |= FILE__READ;
1986         if (file->f_mode & FMODE_WRITE) {
1987                 if (file->f_flags & O_APPEND)
1988                         av |= FILE__APPEND;
1989                 else
1990                         av |= FILE__WRITE;
1991         }
1992         if (!av) {
1993                 /*
1994                  * Special file opened with flags 3 for ioctl-only use.
1995                  */
1996                 av = FILE__IOCTL;
1997         }
1998
1999         return av;
2000 }
2001
2002 /*
2003  * Convert a file to an access vector and include the correct
2004  * open permission.
2005  */
2006 static inline u32 open_file_to_av(struct file *file)
2007 {
2008         u32 av = file_to_av(file);
2009         struct inode *inode = file_inode(file);
2010
2011         if (selinux_policycap_openperm() &&
2012             inode->i_sb->s_magic != SOCKFS_MAGIC)
2013                 av |= FILE__OPEN;
2014
2015         return av;
2016 }
2017
2018 /* Hook functions begin here. */
2019
2020 static int selinux_binder_set_context_mgr(const struct cred *mgr)
2021 {
2022         return avc_has_perm(current_sid(), cred_sid(mgr), SECCLASS_BINDER,
2023                             BINDER__SET_CONTEXT_MGR, NULL);
2024 }
2025
2026 static int selinux_binder_transaction(const struct cred *from,
2027                                       const struct cred *to)
2028 {
2029         u32 mysid = current_sid();
2030         u32 fromsid = cred_sid(from);
2031         u32 tosid = cred_sid(to);
2032         int rc;
2033
2034         if (mysid != fromsid) {
2035                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2036                                   BINDER__IMPERSONATE, NULL);
2037                 if (rc)
2038                         return rc;
2039         }
2040
2041         return avc_has_perm(fromsid, tosid,
2042                             SECCLASS_BINDER, BINDER__CALL, NULL);
2043 }
2044
2045 static int selinux_binder_transfer_binder(const struct cred *from,
2046                                           const struct cred *to)
2047 {
2048         return avc_has_perm(cred_sid(from), cred_sid(to),
2049                             SECCLASS_BINDER, BINDER__TRANSFER,
2050                             NULL);
2051 }
2052
2053 static int selinux_binder_transfer_file(const struct cred *from,
2054                                         const struct cred *to,
2055                                         const struct file *file)
2056 {
2057         u32 sid = cred_sid(to);
2058         struct file_security_struct *fsec = selinux_file(file);
2059         struct dentry *dentry = file->f_path.dentry;
2060         struct inode_security_struct *isec;
2061         struct common_audit_data ad;
2062         int rc;
2063
2064         ad.type = LSM_AUDIT_DATA_PATH;
2065         ad.u.path = file->f_path;
2066
2067         if (sid != fsec->sid) {
2068                 rc = avc_has_perm(sid, fsec->sid,
2069                                   SECCLASS_FD,
2070                                   FD__USE,
2071                                   &ad);
2072                 if (rc)
2073                         return rc;
2074         }
2075
2076 #ifdef CONFIG_BPF_SYSCALL
2077         rc = bpf_fd_pass(file, sid);
2078         if (rc)
2079                 return rc;
2080 #endif
2081
2082         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2083                 return 0;
2084
2085         isec = backing_inode_security(dentry);
2086         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2087                             &ad);
2088 }
2089
2090 static int selinux_ptrace_access_check(struct task_struct *child,
2091                                        unsigned int mode)
2092 {
2093         u32 sid = current_sid();
2094         u32 csid = task_sid_obj(child);
2095
2096         if (mode & PTRACE_MODE_READ)
2097                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ,
2098                                 NULL);
2099
2100         return avc_has_perm(sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE,
2101                         NULL);
2102 }
2103
2104 static int selinux_ptrace_traceme(struct task_struct *parent)
2105 {
2106         return avc_has_perm(task_sid_obj(parent), task_sid_obj(current),
2107                             SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2108 }
2109
2110 static int selinux_capget(const struct task_struct *target, kernel_cap_t *effective,
2111                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2112 {
2113         return avc_has_perm(current_sid(), task_sid_obj(target),
2114                         SECCLASS_PROCESS, PROCESS__GETCAP, NULL);
2115 }
2116
2117 static int selinux_capset(struct cred *new, const struct cred *old,
2118                           const kernel_cap_t *effective,
2119                           const kernel_cap_t *inheritable,
2120                           const kernel_cap_t *permitted)
2121 {
2122         return avc_has_perm(cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2123                             PROCESS__SETCAP, NULL);
2124 }
2125
2126 /*
2127  * (This comment used to live with the selinux_task_setuid hook,
2128  * which was removed).
2129  *
2130  * Since setuid only affects the current process, and since the SELinux
2131  * controls are not based on the Linux identity attributes, SELinux does not
2132  * need to control this operation.  However, SELinux does control the use of
2133  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2134  */
2135
2136 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2137                            int cap, unsigned int opts)
2138 {
2139         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2140 }
2141
2142 static int selinux_quotactl(int cmds, int type, int id, const struct super_block *sb)
2143 {
2144         const struct cred *cred = current_cred();
2145         int rc = 0;
2146
2147         if (!sb)
2148                 return 0;
2149
2150         switch (cmds) {
2151         case Q_SYNC:
2152         case Q_QUOTAON:
2153         case Q_QUOTAOFF:
2154         case Q_SETINFO:
2155         case Q_SETQUOTA:
2156         case Q_XQUOTAOFF:
2157         case Q_XQUOTAON:
2158         case Q_XSETQLIM:
2159                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2160                 break;
2161         case Q_GETFMT:
2162         case Q_GETINFO:
2163         case Q_GETQUOTA:
2164         case Q_XGETQUOTA:
2165         case Q_XGETQSTAT:
2166         case Q_XGETQSTATV:
2167         case Q_XGETNEXTQUOTA:
2168                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2169                 break;
2170         default:
2171                 rc = 0;  /* let the kernel handle invalid cmds */
2172                 break;
2173         }
2174         return rc;
2175 }
2176
2177 static int selinux_quota_on(struct dentry *dentry)
2178 {
2179         const struct cred *cred = current_cred();
2180
2181         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2182 }
2183
2184 static int selinux_syslog(int type)
2185 {
2186         switch (type) {
2187         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2188         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2189                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2190                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2191         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2192         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2193         /* Set level of messages printed to console */
2194         case SYSLOG_ACTION_CONSOLE_LEVEL:
2195                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2196                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2197                                     NULL);
2198         }
2199         /* All other syslog types */
2200         return avc_has_perm(current_sid(), SECINITSID_KERNEL,
2201                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2202 }
2203
2204 /*
2205  * Check that a process has enough memory to allocate a new virtual
2206  * mapping. 0 means there is enough memory for the allocation to
2207  * succeed and -ENOMEM implies there is not.
2208  *
2209  * Do not audit the selinux permission check, as this is applied to all
2210  * processes that allocate mappings.
2211  */
2212 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2213 {
2214         int rc, cap_sys_admin = 0;
2215
2216         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2217                                  CAP_OPT_NOAUDIT, true);
2218         if (rc == 0)
2219                 cap_sys_admin = 1;
2220
2221         return cap_sys_admin;
2222 }
2223
2224 /* binprm security operations */
2225
2226 static u32 ptrace_parent_sid(void)
2227 {
2228         u32 sid = 0;
2229         struct task_struct *tracer;
2230
2231         rcu_read_lock();
2232         tracer = ptrace_parent(current);
2233         if (tracer)
2234                 sid = task_sid_obj(tracer);
2235         rcu_read_unlock();
2236
2237         return sid;
2238 }
2239
2240 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2241                             const struct task_security_struct *old_tsec,
2242                             const struct task_security_struct *new_tsec)
2243 {
2244         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2245         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2246         int rc;
2247         u32 av;
2248
2249         if (!nnp && !nosuid)
2250                 return 0; /* neither NNP nor nosuid */
2251
2252         if (new_tsec->sid == old_tsec->sid)
2253                 return 0; /* No change in credentials */
2254
2255         /*
2256          * If the policy enables the nnp_nosuid_transition policy capability,
2257          * then we permit transitions under NNP or nosuid if the
2258          * policy allows the corresponding permission between
2259          * the old and new contexts.
2260          */
2261         if (selinux_policycap_nnp_nosuid_transition()) {
2262                 av = 0;
2263                 if (nnp)
2264                         av |= PROCESS2__NNP_TRANSITION;
2265                 if (nosuid)
2266                         av |= PROCESS2__NOSUID_TRANSITION;
2267                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2268                                   SECCLASS_PROCESS2, av, NULL);
2269                 if (!rc)
2270                         return 0;
2271         }
2272
2273         /*
2274          * We also permit NNP or nosuid transitions to bounded SIDs,
2275          * i.e. SIDs that are guaranteed to only be allowed a subset
2276          * of the permissions of the current SID.
2277          */
2278         rc = security_bounded_transition(old_tsec->sid,
2279                                          new_tsec->sid);
2280         if (!rc)
2281                 return 0;
2282
2283         /*
2284          * On failure, preserve the errno values for NNP vs nosuid.
2285          * NNP:  Operation not permitted for caller.
2286          * nosuid:  Permission denied to file.
2287          */
2288         if (nnp)
2289                 return -EPERM;
2290         return -EACCES;
2291 }
2292
2293 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2294 {
2295         const struct task_security_struct *old_tsec;
2296         struct task_security_struct *new_tsec;
2297         struct inode_security_struct *isec;
2298         struct common_audit_data ad;
2299         struct inode *inode = file_inode(bprm->file);
2300         int rc;
2301
2302         /* SELinux context only depends on initial program or script and not
2303          * the script interpreter */
2304
2305         old_tsec = selinux_cred(current_cred());
2306         new_tsec = selinux_cred(bprm->cred);
2307         isec = inode_security(inode);
2308
2309         /* Default to the current task SID. */
2310         new_tsec->sid = old_tsec->sid;
2311         new_tsec->osid = old_tsec->sid;
2312
2313         /* Reset fs, key, and sock SIDs on execve. */
2314         new_tsec->create_sid = 0;
2315         new_tsec->keycreate_sid = 0;
2316         new_tsec->sockcreate_sid = 0;
2317
2318         /*
2319          * Before policy is loaded, label any task outside kernel space
2320          * as SECINITSID_INIT, so that any userspace tasks surviving from
2321          * early boot end up with a label different from SECINITSID_KERNEL
2322          * (if the policy chooses to set SECINITSID_INIT != SECINITSID_KERNEL).
2323          */
2324         if (!selinux_initialized()) {
2325                 new_tsec->sid = SECINITSID_INIT;
2326                 /* also clear the exec_sid just in case */
2327                 new_tsec->exec_sid = 0;
2328                 return 0;
2329         }
2330
2331         if (old_tsec->exec_sid) {
2332                 new_tsec->sid = old_tsec->exec_sid;
2333                 /* Reset exec SID on execve. */
2334                 new_tsec->exec_sid = 0;
2335
2336                 /* Fail on NNP or nosuid if not an allowed transition. */
2337                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2338                 if (rc)
2339                         return rc;
2340         } else {
2341                 /* Check for a default transition on this program. */
2342                 rc = security_transition_sid(old_tsec->sid,
2343                                              isec->sid, SECCLASS_PROCESS, NULL,
2344                                              &new_tsec->sid);
2345                 if (rc)
2346                         return rc;
2347
2348                 /*
2349                  * Fallback to old SID on NNP or nosuid if not an allowed
2350                  * transition.
2351                  */
2352                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2353                 if (rc)
2354                         new_tsec->sid = old_tsec->sid;
2355         }
2356
2357         ad.type = LSM_AUDIT_DATA_FILE;
2358         ad.u.file = bprm->file;
2359
2360         if (new_tsec->sid == old_tsec->sid) {
2361                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2362                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2363                 if (rc)
2364                         return rc;
2365         } else {
2366                 /* Check permissions for the transition. */
2367                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2368                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2369                 if (rc)
2370                         return rc;
2371
2372                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2373                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2374                 if (rc)
2375                         return rc;
2376
2377                 /* Check for shared state */
2378                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2379                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2380                                           SECCLASS_PROCESS, PROCESS__SHARE,
2381                                           NULL);
2382                         if (rc)
2383                                 return -EPERM;
2384                 }
2385
2386                 /* Make sure that anyone attempting to ptrace over a task that
2387                  * changes its SID has the appropriate permit */
2388                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2389                         u32 ptsid = ptrace_parent_sid();
2390                         if (ptsid != 0) {
2391                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2392                                                   SECCLASS_PROCESS,
2393                                                   PROCESS__PTRACE, NULL);
2394                                 if (rc)
2395                                         return -EPERM;
2396                         }
2397                 }
2398
2399                 /* Clear any possibly unsafe personality bits on exec: */
2400                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2401
2402                 /* Enable secure mode for SIDs transitions unless
2403                    the noatsecure permission is granted between
2404                    the two SIDs, i.e. ahp returns 0. */
2405                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2406                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2407                                   NULL);
2408                 bprm->secureexec |= !!rc;
2409         }
2410
2411         return 0;
2412 }
2413
2414 static int match_file(const void *p, struct file *file, unsigned fd)
2415 {
2416         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2417 }
2418
2419 /* Derived from fs/exec.c:flush_old_files. */
2420 static inline void flush_unauthorized_files(const struct cred *cred,
2421                                             struct files_struct *files)
2422 {
2423         struct file *file, *devnull = NULL;
2424         struct tty_struct *tty;
2425         int drop_tty = 0;
2426         unsigned n;
2427
2428         tty = get_current_tty();
2429         if (tty) {
2430                 spin_lock(&tty->files_lock);
2431                 if (!list_empty(&tty->tty_files)) {
2432                         struct tty_file_private *file_priv;
2433
2434                         /* Revalidate access to controlling tty.
2435                            Use file_path_has_perm on the tty path directly
2436                            rather than using file_has_perm, as this particular
2437                            open file may belong to another process and we are
2438                            only interested in the inode-based check here. */
2439                         file_priv = list_first_entry(&tty->tty_files,
2440                                                 struct tty_file_private, list);
2441                         file = file_priv->file;
2442                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2443                                 drop_tty = 1;
2444                 }
2445                 spin_unlock(&tty->files_lock);
2446                 tty_kref_put(tty);
2447         }
2448         /* Reset controlling tty. */
2449         if (drop_tty)
2450                 no_tty();
2451
2452         /* Revalidate access to inherited open files. */
2453         n = iterate_fd(files, 0, match_file, cred);
2454         if (!n) /* none found? */
2455                 return;
2456
2457         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2458         if (IS_ERR(devnull))
2459                 devnull = NULL;
2460         /* replace all the matching ones with this */
2461         do {
2462                 replace_fd(n - 1, devnull, 0);
2463         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2464         if (devnull)
2465                 fput(devnull);
2466 }
2467
2468 /*
2469  * Prepare a process for imminent new credential changes due to exec
2470  */
2471 static void selinux_bprm_committing_creds(const struct linux_binprm *bprm)
2472 {
2473         struct task_security_struct *new_tsec;
2474         struct rlimit *rlim, *initrlim;
2475         int rc, i;
2476
2477         new_tsec = selinux_cred(bprm->cred);
2478         if (new_tsec->sid == new_tsec->osid)
2479                 return;
2480
2481         /* Close files for which the new task SID is not authorized. */
2482         flush_unauthorized_files(bprm->cred, current->files);
2483
2484         /* Always clear parent death signal on SID transitions. */
2485         current->pdeath_signal = 0;
2486
2487         /* Check whether the new SID can inherit resource limits from the old
2488          * SID.  If not, reset all soft limits to the lower of the current
2489          * task's hard limit and the init task's soft limit.
2490          *
2491          * Note that the setting of hard limits (even to lower them) can be
2492          * controlled by the setrlimit check.  The inclusion of the init task's
2493          * soft limit into the computation is to avoid resetting soft limits
2494          * higher than the default soft limit for cases where the default is
2495          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2496          */
2497         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2498                           PROCESS__RLIMITINH, NULL);
2499         if (rc) {
2500                 /* protect against do_prlimit() */
2501                 task_lock(current);
2502                 for (i = 0; i < RLIM_NLIMITS; i++) {
2503                         rlim = current->signal->rlim + i;
2504                         initrlim = init_task.signal->rlim + i;
2505                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2506                 }
2507                 task_unlock(current);
2508                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2509                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2510         }
2511 }
2512
2513 /*
2514  * Clean up the process immediately after the installation of new credentials
2515  * due to exec
2516  */
2517 static void selinux_bprm_committed_creds(const struct linux_binprm *bprm)
2518 {
2519         const struct task_security_struct *tsec = selinux_cred(current_cred());
2520         u32 osid, sid;
2521         int rc;
2522
2523         osid = tsec->osid;
2524         sid = tsec->sid;
2525
2526         if (sid == osid)
2527                 return;
2528
2529         /* Check whether the new SID can inherit signal state from the old SID.
2530          * If not, clear itimers to avoid subsequent signal generation and
2531          * flush and unblock signals.
2532          *
2533          * This must occur _after_ the task SID has been updated so that any
2534          * kill done after the flush will be checked against the new SID.
2535          */
2536         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2537         if (rc) {
2538                 clear_itimer();
2539
2540                 spin_lock_irq(&unrcu_pointer(current->sighand)->siglock);
2541                 if (!fatal_signal_pending(current)) {
2542                         flush_sigqueue(&current->pending);
2543                         flush_sigqueue(&current->signal->shared_pending);
2544                         flush_signal_handlers(current, 1);
2545                         sigemptyset(&current->blocked);
2546                         recalc_sigpending();
2547                 }
2548                 spin_unlock_irq(&unrcu_pointer(current->sighand)->siglock);
2549         }
2550
2551         /* Wake up the parent if it is waiting so that it can recheck
2552          * wait permission to the new task SID. */
2553         read_lock(&tasklist_lock);
2554         __wake_up_parent(current, unrcu_pointer(current->real_parent));
2555         read_unlock(&tasklist_lock);
2556 }
2557
2558 /* superblock security operations */
2559
2560 static int selinux_sb_alloc_security(struct super_block *sb)
2561 {
2562         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2563
2564         mutex_init(&sbsec->lock);
2565         INIT_LIST_HEAD(&sbsec->isec_head);
2566         spin_lock_init(&sbsec->isec_lock);
2567         sbsec->sid = SECINITSID_UNLABELED;
2568         sbsec->def_sid = SECINITSID_FILE;
2569         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2570
2571         return 0;
2572 }
2573
2574 static inline int opt_len(const char *s)
2575 {
2576         bool open_quote = false;
2577         int len;
2578         char c;
2579
2580         for (len = 0; (c = s[len]) != '\0'; len++) {
2581                 if (c == '"')
2582                         open_quote = !open_quote;
2583                 if (c == ',' && !open_quote)
2584                         break;
2585         }
2586         return len;
2587 }
2588
2589 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2590 {
2591         char *from = options;
2592         char *to = options;
2593         bool first = true;
2594         int rc;
2595
2596         while (1) {
2597                 int len = opt_len(from);
2598                 int token;
2599                 char *arg = NULL;
2600
2601                 token = match_opt_prefix(from, len, &arg);
2602
2603                 if (token != Opt_error) {
2604                         char *p, *q;
2605
2606                         /* strip quotes */
2607                         if (arg) {
2608                                 for (p = q = arg; p < from + len; p++) {
2609                                         char c = *p;
2610                                         if (c != '"')
2611                                                 *q++ = c;
2612                                 }
2613                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2614                                 if (!arg) {
2615                                         rc = -ENOMEM;
2616                                         goto free_opt;
2617                                 }
2618                         }
2619                         rc = selinux_add_opt(token, arg, mnt_opts);
2620                         kfree(arg);
2621                         arg = NULL;
2622                         if (unlikely(rc)) {
2623                                 goto free_opt;
2624                         }
2625                 } else {
2626                         if (!first) {   // copy with preceding comma
2627                                 from--;
2628                                 len++;
2629                         }
2630                         if (to != from)
2631                                 memmove(to, from, len);
2632                         to += len;
2633                         first = false;
2634                 }
2635                 if (!from[len])
2636                         break;
2637                 from += len + 1;
2638         }
2639         *to = '\0';
2640         return 0;
2641
2642 free_opt:
2643         if (*mnt_opts) {
2644                 selinux_free_mnt_opts(*mnt_opts);
2645                 *mnt_opts = NULL;
2646         }
2647         return rc;
2648 }
2649
2650 static int selinux_sb_mnt_opts_compat(struct super_block *sb, void *mnt_opts)
2651 {
2652         struct selinux_mnt_opts *opts = mnt_opts;
2653         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2654
2655         /*
2656          * Superblock not initialized (i.e. no options) - reject if any
2657          * options specified, otherwise accept.
2658          */
2659         if (!(sbsec->flags & SE_SBINITIALIZED))
2660                 return opts ? 1 : 0;
2661
2662         /*
2663          * Superblock initialized and no options specified - reject if
2664          * superblock has any options set, otherwise accept.
2665          */
2666         if (!opts)
2667                 return (sbsec->flags & SE_MNTMASK) ? 1 : 0;
2668
2669         if (opts->fscontext_sid) {
2670                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2671                                opts->fscontext_sid))
2672                         return 1;
2673         }
2674         if (opts->context_sid) {
2675                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2676                                opts->context_sid))
2677                         return 1;
2678         }
2679         if (opts->rootcontext_sid) {
2680                 struct inode_security_struct *root_isec;
2681
2682                 root_isec = backing_inode_security(sb->s_root);
2683                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2684                                opts->rootcontext_sid))
2685                         return 1;
2686         }
2687         if (opts->defcontext_sid) {
2688                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2689                                opts->defcontext_sid))
2690                         return 1;
2691         }
2692         return 0;
2693 }
2694
2695 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2696 {
2697         struct selinux_mnt_opts *opts = mnt_opts;
2698         struct superblock_security_struct *sbsec = selinux_superblock(sb);
2699
2700         if (!(sbsec->flags & SE_SBINITIALIZED))
2701                 return 0;
2702
2703         if (!opts)
2704                 return 0;
2705
2706         if (opts->fscontext_sid) {
2707                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
2708                                opts->fscontext_sid))
2709                         goto out_bad_option;
2710         }
2711         if (opts->context_sid) {
2712                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
2713                                opts->context_sid))
2714                         goto out_bad_option;
2715         }
2716         if (opts->rootcontext_sid) {
2717                 struct inode_security_struct *root_isec;
2718                 root_isec = backing_inode_security(sb->s_root);
2719                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
2720                                opts->rootcontext_sid))
2721                         goto out_bad_option;
2722         }
2723         if (opts->defcontext_sid) {
2724                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
2725                                opts->defcontext_sid))
2726                         goto out_bad_option;
2727         }
2728         return 0;
2729
2730 out_bad_option:
2731         pr_warn("SELinux: unable to change security options "
2732                "during remount (dev %s, type=%s)\n", sb->s_id,
2733                sb->s_type->name);
2734         return -EINVAL;
2735 }
2736
2737 static int selinux_sb_kern_mount(const struct super_block *sb)
2738 {
2739         const struct cred *cred = current_cred();
2740         struct common_audit_data ad;
2741
2742         ad.type = LSM_AUDIT_DATA_DENTRY;
2743         ad.u.dentry = sb->s_root;
2744         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2745 }
2746
2747 static int selinux_sb_statfs(struct dentry *dentry)
2748 {
2749         const struct cred *cred = current_cred();
2750         struct common_audit_data ad;
2751
2752         ad.type = LSM_AUDIT_DATA_DENTRY;
2753         ad.u.dentry = dentry->d_sb->s_root;
2754         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2755 }
2756
2757 static int selinux_mount(const char *dev_name,
2758                          const struct path *path,
2759                          const char *type,
2760                          unsigned long flags,
2761                          void *data)
2762 {
2763         const struct cred *cred = current_cred();
2764
2765         if (flags & MS_REMOUNT)
2766                 return superblock_has_perm(cred, path->dentry->d_sb,
2767                                            FILESYSTEM__REMOUNT, NULL);
2768         else
2769                 return path_has_perm(cred, path, FILE__MOUNTON);
2770 }
2771
2772 static int selinux_move_mount(const struct path *from_path,
2773                               const struct path *to_path)
2774 {
2775         const struct cred *cred = current_cred();
2776
2777         return path_has_perm(cred, to_path, FILE__MOUNTON);
2778 }
2779
2780 static int selinux_umount(struct vfsmount *mnt, int flags)
2781 {
2782         const struct cred *cred = current_cred();
2783
2784         return superblock_has_perm(cred, mnt->mnt_sb,
2785                                    FILESYSTEM__UNMOUNT, NULL);
2786 }
2787
2788 static int selinux_fs_context_submount(struct fs_context *fc,
2789                                    struct super_block *reference)
2790 {
2791         const struct superblock_security_struct *sbsec = selinux_superblock(reference);
2792         struct selinux_mnt_opts *opts;
2793
2794         /*
2795          * Ensure that fc->security remains NULL when no options are set
2796          * as expected by selinux_set_mnt_opts().
2797          */
2798         if (!(sbsec->flags & (FSCONTEXT_MNT|CONTEXT_MNT|DEFCONTEXT_MNT)))
2799                 return 0;
2800
2801         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
2802         if (!opts)
2803                 return -ENOMEM;
2804
2805         if (sbsec->flags & FSCONTEXT_MNT)
2806                 opts->fscontext_sid = sbsec->sid;
2807         if (sbsec->flags & CONTEXT_MNT)
2808                 opts->context_sid = sbsec->mntpoint_sid;
2809         if (sbsec->flags & DEFCONTEXT_MNT)
2810                 opts->defcontext_sid = sbsec->def_sid;
2811         fc->security = opts;
2812         return 0;
2813 }
2814
2815 static int selinux_fs_context_dup(struct fs_context *fc,
2816                                   struct fs_context *src_fc)
2817 {
2818         const struct selinux_mnt_opts *src = src_fc->security;
2819
2820         if (!src)
2821                 return 0;
2822
2823         fc->security = kmemdup(src, sizeof(*src), GFP_KERNEL);
2824         return fc->security ? 0 : -ENOMEM;
2825 }
2826
2827 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2828         fsparam_string(CONTEXT_STR,     Opt_context),
2829         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2830         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2831         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2832         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2833         {}
2834 };
2835
2836 static int selinux_fs_context_parse_param(struct fs_context *fc,
2837                                           struct fs_parameter *param)
2838 {
2839         struct fs_parse_result result;
2840         int opt;
2841
2842         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2843         if (opt < 0)
2844                 return opt;
2845
2846         return selinux_add_opt(opt, param->string, &fc->security);
2847 }
2848
2849 /* inode security operations */
2850
2851 static int selinux_inode_alloc_security(struct inode *inode)
2852 {
2853         struct inode_security_struct *isec = selinux_inode(inode);
2854         u32 sid = current_sid();
2855
2856         spin_lock_init(&isec->lock);
2857         INIT_LIST_HEAD(&isec->list);
2858         isec->inode = inode;
2859         isec->sid = SECINITSID_UNLABELED;
2860         isec->sclass = SECCLASS_FILE;
2861         isec->task_sid = sid;
2862         isec->initialized = LABEL_INVALID;
2863
2864         return 0;
2865 }
2866
2867 static void selinux_inode_free_security(struct inode *inode)
2868 {
2869         inode_free_security(inode);
2870 }
2871
2872 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2873                                         const struct qstr *name,
2874                                         const char **xattr_name, void **ctx,
2875                                         u32 *ctxlen)
2876 {
2877         u32 newsid;
2878         int rc;
2879
2880         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2881                                            d_inode(dentry->d_parent), name,
2882                                            inode_mode_to_security_class(mode),
2883                                            &newsid);
2884         if (rc)
2885                 return rc;
2886
2887         if (xattr_name)
2888                 *xattr_name = XATTR_NAME_SELINUX;
2889
2890         return security_sid_to_context(newsid, (char **)ctx,
2891                                        ctxlen);
2892 }
2893
2894 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2895                                           struct qstr *name,
2896                                           const struct cred *old,
2897                                           struct cred *new)
2898 {
2899         u32 newsid;
2900         int rc;
2901         struct task_security_struct *tsec;
2902
2903         rc = selinux_determine_inode_label(selinux_cred(old),
2904                                            d_inode(dentry->d_parent), name,
2905                                            inode_mode_to_security_class(mode),
2906                                            &newsid);
2907         if (rc)
2908                 return rc;
2909
2910         tsec = selinux_cred(new);
2911         tsec->create_sid = newsid;
2912         return 0;
2913 }
2914
2915 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2916                                        const struct qstr *qstr,
2917                                        struct xattr *xattrs, int *xattr_count)
2918 {
2919         const struct task_security_struct *tsec = selinux_cred(current_cred());
2920         struct superblock_security_struct *sbsec;
2921         struct xattr *xattr = lsm_get_xattr_slot(xattrs, xattr_count);
2922         u32 newsid, clen;
2923         u16 newsclass;
2924         int rc;
2925         char *context;
2926
2927         sbsec = selinux_superblock(dir->i_sb);
2928
2929         newsid = tsec->create_sid;
2930         newsclass = inode_mode_to_security_class(inode->i_mode);
2931         rc = selinux_determine_inode_label(tsec, dir, qstr, newsclass, &newsid);
2932         if (rc)
2933                 return rc;
2934
2935         /* Possibly defer initialization to selinux_complete_init. */
2936         if (sbsec->flags & SE_SBINITIALIZED) {
2937                 struct inode_security_struct *isec = selinux_inode(inode);
2938                 isec->sclass = newsclass;
2939                 isec->sid = newsid;
2940                 isec->initialized = LABEL_INITIALIZED;
2941         }
2942
2943         if (!selinux_initialized() ||
2944             !(sbsec->flags & SBLABEL_MNT))
2945                 return -EOPNOTSUPP;
2946
2947         if (xattr) {
2948                 rc = security_sid_to_context_force(newsid,
2949                                                    &context, &clen);
2950                 if (rc)
2951                         return rc;
2952                 xattr->value = context;
2953                 xattr->value_len = clen;
2954                 xattr->name = XATTR_SELINUX_SUFFIX;
2955         }
2956
2957         return 0;
2958 }
2959
2960 static int selinux_inode_init_security_anon(struct inode *inode,
2961                                             const struct qstr *name,
2962                                             const struct inode *context_inode)
2963 {
2964         const struct task_security_struct *tsec = selinux_cred(current_cred());
2965         struct common_audit_data ad;
2966         struct inode_security_struct *isec;
2967         int rc;
2968
2969         if (unlikely(!selinux_initialized()))
2970                 return 0;
2971
2972         isec = selinux_inode(inode);
2973
2974         /*
2975          * We only get here once per ephemeral inode.  The inode has
2976          * been initialized via inode_alloc_security but is otherwise
2977          * untouched.
2978          */
2979
2980         if (context_inode) {
2981                 struct inode_security_struct *context_isec =
2982                         selinux_inode(context_inode);
2983                 if (context_isec->initialized != LABEL_INITIALIZED) {
2984                         pr_err("SELinux:  context_inode is not initialized\n");
2985                         return -EACCES;
2986                 }
2987
2988                 isec->sclass = context_isec->sclass;
2989                 isec->sid = context_isec->sid;
2990         } else {
2991                 isec->sclass = SECCLASS_ANON_INODE;
2992                 rc = security_transition_sid(
2993                         tsec->sid, tsec->sid,
2994                         isec->sclass, name, &isec->sid);
2995                 if (rc)
2996                         return rc;
2997         }
2998
2999         isec->initialized = LABEL_INITIALIZED;
3000         /*
3001          * Now that we've initialized security, check whether we're
3002          * allowed to actually create this type of anonymous inode.
3003          */
3004
3005         ad.type = LSM_AUDIT_DATA_ANONINODE;
3006         ad.u.anonclass = name ? (const char *)name->name : "?";
3007
3008         return avc_has_perm(tsec->sid,
3009                             isec->sid,
3010                             isec->sclass,
3011                             FILE__CREATE,
3012                             &ad);
3013 }
3014
3015 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
3016 {
3017         return may_create(dir, dentry, SECCLASS_FILE);
3018 }
3019
3020 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
3021 {
3022         return may_link(dir, old_dentry, MAY_LINK);
3023 }
3024
3025 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
3026 {
3027         return may_link(dir, dentry, MAY_UNLINK);
3028 }
3029
3030 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
3031 {
3032         return may_create(dir, dentry, SECCLASS_LNK_FILE);
3033 }
3034
3035 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
3036 {
3037         return may_create(dir, dentry, SECCLASS_DIR);
3038 }
3039
3040 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
3041 {
3042         return may_link(dir, dentry, MAY_RMDIR);
3043 }
3044
3045 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
3046 {
3047         return may_create(dir, dentry, inode_mode_to_security_class(mode));
3048 }
3049
3050 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
3051                                 struct inode *new_inode, struct dentry *new_dentry)
3052 {
3053         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
3054 }
3055
3056 static int selinux_inode_readlink(struct dentry *dentry)
3057 {
3058         const struct cred *cred = current_cred();
3059
3060         return dentry_has_perm(cred, dentry, FILE__READ);
3061 }
3062
3063 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
3064                                      bool rcu)
3065 {
3066         const struct cred *cred = current_cred();
3067         struct common_audit_data ad;
3068         struct inode_security_struct *isec;
3069         u32 sid;
3070
3071         ad.type = LSM_AUDIT_DATA_DENTRY;
3072         ad.u.dentry = dentry;
3073         sid = cred_sid(cred);
3074         isec = inode_security_rcu(inode, rcu);
3075         if (IS_ERR(isec))
3076                 return PTR_ERR(isec);
3077
3078         return avc_has_perm(sid, isec->sid, isec->sclass, FILE__READ, &ad);
3079 }
3080
3081 static noinline int audit_inode_permission(struct inode *inode,
3082                                            u32 perms, u32 audited, u32 denied,
3083                                            int result)
3084 {
3085         struct common_audit_data ad;
3086         struct inode_security_struct *isec = selinux_inode(inode);
3087
3088         ad.type = LSM_AUDIT_DATA_INODE;
3089         ad.u.inode = inode;
3090
3091         return slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3092                             audited, denied, result, &ad);
3093 }
3094
3095 static int selinux_inode_permission(struct inode *inode, int mask)
3096 {
3097         const struct cred *cred = current_cred();
3098         u32 perms;
3099         bool from_access;
3100         bool no_block = mask & MAY_NOT_BLOCK;
3101         struct inode_security_struct *isec;
3102         u32 sid;
3103         struct av_decision avd;
3104         int rc, rc2;
3105         u32 audited, denied;
3106
3107         from_access = mask & MAY_ACCESS;
3108         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3109
3110         /* No permission to check.  Existence test. */
3111         if (!mask)
3112                 return 0;
3113
3114         if (unlikely(IS_PRIVATE(inode)))
3115                 return 0;
3116
3117         perms = file_mask_to_av(inode->i_mode, mask);
3118
3119         sid = cred_sid(cred);
3120         isec = inode_security_rcu(inode, no_block);
3121         if (IS_ERR(isec))
3122                 return PTR_ERR(isec);
3123
3124         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0,
3125                                   &avd);
3126         audited = avc_audit_required(perms, &avd, rc,
3127                                      from_access ? FILE__AUDIT_ACCESS : 0,
3128                                      &denied);
3129         if (likely(!audited))
3130                 return rc;
3131
3132         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3133         if (rc2)
3134                 return rc2;
3135         return rc;
3136 }
3137
3138 static int selinux_inode_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
3139                                  struct iattr *iattr)
3140 {
3141         const struct cred *cred = current_cred();
3142         struct inode *inode = d_backing_inode(dentry);
3143         unsigned int ia_valid = iattr->ia_valid;
3144         __u32 av = FILE__WRITE;
3145
3146         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3147         if (ia_valid & ATTR_FORCE) {
3148                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3149                               ATTR_FORCE);
3150                 if (!ia_valid)
3151                         return 0;
3152         }
3153
3154         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3155                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3156                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3157
3158         if (selinux_policycap_openperm() &&
3159             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3160             (ia_valid & ATTR_SIZE) &&
3161             !(ia_valid & ATTR_FILE))
3162                 av |= FILE__OPEN;
3163
3164         return dentry_has_perm(cred, dentry, av);
3165 }
3166
3167 static int selinux_inode_getattr(const struct path *path)
3168 {
3169         return path_has_perm(current_cred(), path, FILE__GETATTR);
3170 }
3171
3172 static bool has_cap_mac_admin(bool audit)
3173 {
3174         const struct cred *cred = current_cred();
3175         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3176
3177         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3178                 return false;
3179         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3180                 return false;
3181         return true;
3182 }
3183
3184 static int selinux_inode_setxattr(struct mnt_idmap *idmap,
3185                                   struct dentry *dentry, const char *name,
3186                                   const void *value, size_t size, int flags)
3187 {
3188         struct inode *inode = d_backing_inode(dentry);
3189         struct inode_security_struct *isec;
3190         struct superblock_security_struct *sbsec;
3191         struct common_audit_data ad;
3192         u32 newsid, sid = current_sid();
3193         int rc = 0;
3194
3195         if (strcmp(name, XATTR_NAME_SELINUX)) {
3196                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3197                 if (rc)
3198                         return rc;
3199
3200                 /* Not an attribute we recognize, so just check the
3201                    ordinary setattr permission. */
3202                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3203         }
3204
3205         if (!selinux_initialized())
3206                 return (inode_owner_or_capable(idmap, inode) ? 0 : -EPERM);
3207
3208         sbsec = selinux_superblock(inode->i_sb);
3209         if (!(sbsec->flags & SBLABEL_MNT))
3210                 return -EOPNOTSUPP;
3211
3212         if (!inode_owner_or_capable(idmap, inode))
3213                 return -EPERM;
3214
3215         ad.type = LSM_AUDIT_DATA_DENTRY;
3216         ad.u.dentry = dentry;
3217
3218         isec = backing_inode_security(dentry);
3219         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3220                           FILE__RELABELFROM, &ad);
3221         if (rc)
3222                 return rc;
3223
3224         rc = security_context_to_sid(value, size, &newsid,
3225                                      GFP_KERNEL);
3226         if (rc == -EINVAL) {
3227                 if (!has_cap_mac_admin(true)) {
3228                         struct audit_buffer *ab;
3229                         size_t audit_size;
3230
3231                         /* We strip a nul only if it is at the end, otherwise the
3232                          * context contains a nul and we should audit that */
3233                         if (value) {
3234                                 const char *str = value;
3235
3236                                 if (str[size - 1] == '\0')
3237                                         audit_size = size - 1;
3238                                 else
3239                                         audit_size = size;
3240                         } else {
3241                                 audit_size = 0;
3242                         }
3243                         ab = audit_log_start(audit_context(),
3244                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3245                         if (!ab)
3246                                 return rc;
3247                         audit_log_format(ab, "op=setxattr invalid_context=");
3248                         audit_log_n_untrustedstring(ab, value, audit_size);
3249                         audit_log_end(ab);
3250
3251                         return rc;
3252                 }
3253                 rc = security_context_to_sid_force(value,
3254                                                    size, &newsid);
3255         }
3256         if (rc)
3257                 return rc;
3258
3259         rc = avc_has_perm(sid, newsid, isec->sclass,
3260                           FILE__RELABELTO, &ad);
3261         if (rc)
3262                 return rc;
3263
3264         rc = security_validate_transition(isec->sid, newsid,
3265                                           sid, isec->sclass);
3266         if (rc)
3267                 return rc;
3268
3269         return avc_has_perm(newsid,
3270                             sbsec->sid,
3271                             SECCLASS_FILESYSTEM,
3272                             FILESYSTEM__ASSOCIATE,
3273                             &ad);
3274 }
3275
3276 static int selinux_inode_set_acl(struct mnt_idmap *idmap,
3277                                  struct dentry *dentry, const char *acl_name,
3278                                  struct posix_acl *kacl)
3279 {
3280         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3281 }
3282
3283 static int selinux_inode_get_acl(struct mnt_idmap *idmap,
3284                                  struct dentry *dentry, const char *acl_name)
3285 {
3286         return dentry_has_perm(current_cred(), dentry, FILE__GETATTR);
3287 }
3288
3289 static int selinux_inode_remove_acl(struct mnt_idmap *idmap,
3290                                     struct dentry *dentry, const char *acl_name)
3291 {
3292         return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3293 }
3294
3295 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3296                                         const void *value, size_t size,
3297                                         int flags)
3298 {
3299         struct inode *inode = d_backing_inode(dentry);
3300         struct inode_security_struct *isec;
3301         u32 newsid;
3302         int rc;
3303
3304         if (strcmp(name, XATTR_NAME_SELINUX)) {
3305                 /* Not an attribute we recognize, so nothing to do. */
3306                 return;
3307         }
3308
3309         if (!selinux_initialized()) {
3310                 /* If we haven't even been initialized, then we can't validate
3311                  * against a policy, so leave the label as invalid. It may
3312                  * resolve to a valid label on the next revalidation try if
3313                  * we've since initialized.
3314                  */
3315                 return;
3316         }
3317
3318         rc = security_context_to_sid_force(value, size,
3319                                            &newsid);
3320         if (rc) {
3321                 pr_err("SELinux:  unable to map context to SID"
3322                        "for (%s, %lu), rc=%d\n",
3323                        inode->i_sb->s_id, inode->i_ino, -rc);
3324                 return;
3325         }
3326
3327         isec = backing_inode_security(dentry);
3328         spin_lock(&isec->lock);
3329         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3330         isec->sid = newsid;
3331         isec->initialized = LABEL_INITIALIZED;
3332         spin_unlock(&isec->lock);
3333 }
3334
3335 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3336 {
3337         const struct cred *cred = current_cred();
3338
3339         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3340 }
3341
3342 static int selinux_inode_listxattr(struct dentry *dentry)
3343 {
3344         const struct cred *cred = current_cred();
3345
3346         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3347 }
3348
3349 static int selinux_inode_removexattr(struct mnt_idmap *idmap,
3350                                      struct dentry *dentry, const char *name)
3351 {
3352         if (strcmp(name, XATTR_NAME_SELINUX)) {
3353                 int rc = cap_inode_removexattr(idmap, dentry, name);
3354                 if (rc)
3355                         return rc;
3356
3357                 /* Not an attribute we recognize, so just check the
3358                    ordinary setattr permission. */
3359                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3360         }
3361
3362         if (!selinux_initialized())
3363                 return 0;
3364
3365         /* No one is allowed to remove a SELinux security label.
3366            You can change the label, but all data must be labeled. */
3367         return -EACCES;
3368 }
3369
3370 static int selinux_path_notify(const struct path *path, u64 mask,
3371                                                 unsigned int obj_type)
3372 {
3373         int ret;
3374         u32 perm;
3375
3376         struct common_audit_data ad;
3377
3378         ad.type = LSM_AUDIT_DATA_PATH;
3379         ad.u.path = *path;
3380
3381         /*
3382          * Set permission needed based on the type of mark being set.
3383          * Performs an additional check for sb watches.
3384          */
3385         switch (obj_type) {
3386         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3387                 perm = FILE__WATCH_MOUNT;
3388                 break;
3389         case FSNOTIFY_OBJ_TYPE_SB:
3390                 perm = FILE__WATCH_SB;
3391                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3392                                                 FILESYSTEM__WATCH, &ad);
3393                 if (ret)
3394                         return ret;
3395                 break;
3396         case FSNOTIFY_OBJ_TYPE_INODE:
3397                 perm = FILE__WATCH;
3398                 break;
3399         default:
3400                 return -EINVAL;
3401         }
3402
3403         /* blocking watches require the file:watch_with_perm permission */
3404         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3405                 perm |= FILE__WATCH_WITH_PERM;
3406
3407         /* watches on read-like events need the file:watch_reads permission */
3408         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3409                 perm |= FILE__WATCH_READS;
3410
3411         return path_has_perm(current_cred(), path, perm);
3412 }
3413
3414 /*
3415  * Copy the inode security context value to the user.
3416  *
3417  * Permission check is handled by selinux_inode_getxattr hook.
3418  */
3419 static int selinux_inode_getsecurity(struct mnt_idmap *idmap,
3420                                      struct inode *inode, const char *name,
3421                                      void **buffer, bool alloc)
3422 {
3423         u32 size;
3424         int error;
3425         char *context = NULL;
3426         struct inode_security_struct *isec;
3427
3428         /*
3429          * If we're not initialized yet, then we can't validate contexts, so
3430          * just let vfs_getxattr fall back to using the on-disk xattr.
3431          */
3432         if (!selinux_initialized() ||
3433             strcmp(name, XATTR_SELINUX_SUFFIX))
3434                 return -EOPNOTSUPP;
3435
3436         /*
3437          * If the caller has CAP_MAC_ADMIN, then get the raw context
3438          * value even if it is not defined by current policy; otherwise,
3439          * use the in-core value under current policy.
3440          * Use the non-auditing forms of the permission checks since
3441          * getxattr may be called by unprivileged processes commonly
3442          * and lack of permission just means that we fall back to the
3443          * in-core context value, not a denial.
3444          */
3445         isec = inode_security(inode);
3446         if (has_cap_mac_admin(false))
3447                 error = security_sid_to_context_force(isec->sid, &context,
3448                                                       &size);
3449         else
3450                 error = security_sid_to_context(isec->sid,
3451                                                 &context, &size);
3452         if (error)
3453                 return error;
3454         error = size;
3455         if (alloc) {
3456                 *buffer = context;
3457                 goto out_nofree;
3458         }
3459         kfree(context);
3460 out_nofree:
3461         return error;
3462 }
3463
3464 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3465                                      const void *value, size_t size, int flags)
3466 {
3467         struct inode_security_struct *isec = inode_security_novalidate(inode);
3468         struct superblock_security_struct *sbsec;
3469         u32 newsid;
3470         int rc;
3471
3472         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3473                 return -EOPNOTSUPP;
3474
3475         sbsec = selinux_superblock(inode->i_sb);
3476         if (!(sbsec->flags & SBLABEL_MNT))
3477                 return -EOPNOTSUPP;
3478
3479         if (!value || !size)
3480                 return -EACCES;
3481
3482         rc = security_context_to_sid(value, size, &newsid,
3483                                      GFP_KERNEL);
3484         if (rc)
3485                 return rc;
3486
3487         spin_lock(&isec->lock);
3488         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3489         isec->sid = newsid;
3490         isec->initialized = LABEL_INITIALIZED;
3491         spin_unlock(&isec->lock);
3492         return 0;
3493 }
3494
3495 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3496 {
3497         const int len = sizeof(XATTR_NAME_SELINUX);
3498
3499         if (!selinux_initialized())
3500                 return 0;
3501
3502         if (buffer && len <= buffer_size)
3503                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3504         return len;
3505 }
3506
3507 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3508 {
3509         struct inode_security_struct *isec = inode_security_novalidate(inode);
3510         *secid = isec->sid;
3511 }
3512
3513 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3514 {
3515         u32 sid;
3516         struct task_security_struct *tsec;
3517         struct cred *new_creds = *new;
3518
3519         if (new_creds == NULL) {
3520                 new_creds = prepare_creds();
3521                 if (!new_creds)
3522                         return -ENOMEM;
3523         }
3524
3525         tsec = selinux_cred(new_creds);
3526         /* Get label from overlay inode and set it in create_sid */
3527         selinux_inode_getsecid(d_inode(src), &sid);
3528         tsec->create_sid = sid;
3529         *new = new_creds;
3530         return 0;
3531 }
3532
3533 static int selinux_inode_copy_up_xattr(const char *name)
3534 {
3535         /* The copy_up hook above sets the initial context on an inode, but we
3536          * don't then want to overwrite it by blindly copying all the lower
3537          * xattrs up.  Instead, filter out SELinux-related xattrs following
3538          * policy load.
3539          */
3540         if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
3541                 return 1; /* Discard */
3542         /*
3543          * Any other attribute apart from SELINUX is not claimed, supported
3544          * by selinux.
3545          */
3546         return -EOPNOTSUPP;
3547 }
3548
3549 /* kernfs node operations */
3550
3551 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3552                                         struct kernfs_node *kn)
3553 {
3554         const struct task_security_struct *tsec = selinux_cred(current_cred());
3555         u32 parent_sid, newsid, clen;
3556         int rc;
3557         char *context;
3558
3559         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3560         if (rc == -ENODATA)
3561                 return 0;
3562         else if (rc < 0)
3563                 return rc;
3564
3565         clen = (u32)rc;
3566         context = kmalloc(clen, GFP_KERNEL);
3567         if (!context)
3568                 return -ENOMEM;
3569
3570         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3571         if (rc < 0) {
3572                 kfree(context);
3573                 return rc;
3574         }
3575
3576         rc = security_context_to_sid(context, clen, &parent_sid,
3577                                      GFP_KERNEL);
3578         kfree(context);
3579         if (rc)
3580                 return rc;
3581
3582         if (tsec->create_sid) {
3583                 newsid = tsec->create_sid;
3584         } else {
3585                 u16 secclass = inode_mode_to_security_class(kn->mode);
3586                 struct qstr q;
3587
3588                 q.name = kn->name;
3589                 q.hash_len = hashlen_string(kn_dir, kn->name);
3590
3591                 rc = security_transition_sid(tsec->sid,
3592                                              parent_sid, secclass, &q,
3593                                              &newsid);
3594                 if (rc)
3595                         return rc;
3596         }
3597
3598         rc = security_sid_to_context_force(newsid,
3599                                            &context, &clen);
3600         if (rc)
3601                 return rc;
3602
3603         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3604                               XATTR_CREATE);
3605         kfree(context);
3606         return rc;
3607 }
3608
3609
3610 /* file security operations */
3611
3612 static int selinux_revalidate_file_permission(struct file *file, int mask)
3613 {
3614         const struct cred *cred = current_cred();
3615         struct inode *inode = file_inode(file);
3616
3617         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3618         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3619                 mask |= MAY_APPEND;
3620
3621         return file_has_perm(cred, file,
3622                              file_mask_to_av(inode->i_mode, mask));
3623 }
3624
3625 static int selinux_file_permission(struct file *file, int mask)
3626 {
3627         struct inode *inode = file_inode(file);
3628         struct file_security_struct *fsec = selinux_file(file);
3629         struct inode_security_struct *isec;
3630         u32 sid = current_sid();
3631
3632         if (!mask)
3633                 /* No permission to check.  Existence test. */
3634                 return 0;
3635
3636         isec = inode_security(inode);
3637         if (sid == fsec->sid && fsec->isid == isec->sid &&
3638             fsec->pseqno == avc_policy_seqno())
3639                 /* No change since file_open check. */
3640                 return 0;
3641
3642         return selinux_revalidate_file_permission(file, mask);
3643 }
3644
3645 static int selinux_file_alloc_security(struct file *file)
3646 {
3647         struct file_security_struct *fsec = selinux_file(file);
3648         u32 sid = current_sid();
3649
3650         fsec->sid = sid;
3651         fsec->fown_sid = sid;
3652
3653         return 0;
3654 }
3655
3656 /*
3657  * Check whether a task has the ioctl permission and cmd
3658  * operation to an inode.
3659  */
3660 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3661                 u32 requested, u16 cmd)
3662 {
3663         struct common_audit_data ad;
3664         struct file_security_struct *fsec = selinux_file(file);
3665         struct inode *inode = file_inode(file);
3666         struct inode_security_struct *isec;
3667         struct lsm_ioctlop_audit ioctl;
3668         u32 ssid = cred_sid(cred);
3669         int rc;
3670         u8 driver = cmd >> 8;
3671         u8 xperm = cmd & 0xff;
3672
3673         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3674         ad.u.op = &ioctl;
3675         ad.u.op->cmd = cmd;
3676         ad.u.op->path = file->f_path;
3677
3678         if (ssid != fsec->sid) {
3679                 rc = avc_has_perm(ssid, fsec->sid,
3680                                 SECCLASS_FD,
3681                                 FD__USE,
3682                                 &ad);
3683                 if (rc)
3684                         goto out;
3685         }
3686
3687         if (unlikely(IS_PRIVATE(inode)))
3688                 return 0;
3689
3690         isec = inode_security(inode);
3691         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3692                                     requested, driver, xperm, &ad);
3693 out:
3694         return rc;
3695 }
3696
3697 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3698                               unsigned long arg)
3699 {
3700         const struct cred *cred = current_cred();
3701         int error = 0;
3702
3703         switch (cmd) {
3704         case FIONREAD:
3705         case FIBMAP:
3706         case FIGETBSZ:
3707         case FS_IOC_GETFLAGS:
3708         case FS_IOC_GETVERSION:
3709                 error = file_has_perm(cred, file, FILE__GETATTR);
3710                 break;
3711
3712         case FS_IOC_SETFLAGS:
3713         case FS_IOC_SETVERSION:
3714                 error = file_has_perm(cred, file, FILE__SETATTR);
3715                 break;
3716
3717         /* sys_ioctl() checks */
3718         case FIONBIO:
3719         case FIOASYNC:
3720                 error = file_has_perm(cred, file, 0);
3721                 break;
3722
3723         case KDSKBENT:
3724         case KDSKBSENT:
3725                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3726                                             CAP_OPT_NONE, true);
3727                 break;
3728
3729         case FIOCLEX:
3730         case FIONCLEX:
3731                 if (!selinux_policycap_ioctl_skip_cloexec())
3732                         error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3733                 break;
3734
3735         /* default case assumes that the command will go
3736          * to the file's ioctl() function.
3737          */
3738         default:
3739                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3740         }
3741         return error;
3742 }
3743
3744 static int selinux_file_ioctl_compat(struct file *file, unsigned int cmd,
3745                               unsigned long arg)
3746 {
3747         /*
3748          * If we are in a 64-bit kernel running 32-bit userspace, we need to
3749          * make sure we don't compare 32-bit flags to 64-bit flags.
3750          */
3751         switch (cmd) {
3752         case FS_IOC32_GETFLAGS:
3753                 cmd = FS_IOC_GETFLAGS;
3754                 break;
3755         case FS_IOC32_SETFLAGS:
3756                 cmd = FS_IOC_SETFLAGS;
3757                 break;
3758         case FS_IOC32_GETVERSION:
3759                 cmd = FS_IOC_GETVERSION;
3760                 break;
3761         case FS_IOC32_SETVERSION:
3762                 cmd = FS_IOC_SETVERSION;
3763                 break;
3764         default:
3765                 break;
3766         }
3767
3768         return selinux_file_ioctl(file, cmd, arg);
3769 }
3770
3771 static int default_noexec __ro_after_init;
3772
3773 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3774 {
3775         const struct cred *cred = current_cred();
3776         u32 sid = cred_sid(cred);
3777         int rc = 0;
3778
3779         if (default_noexec &&
3780             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3781                                    (!shared && (prot & PROT_WRITE)))) {
3782                 /*
3783                  * We are making executable an anonymous mapping or a
3784                  * private file mapping that will also be writable.
3785                  * This has an additional check.
3786                  */
3787                 rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3788                                   PROCESS__EXECMEM, NULL);
3789                 if (rc)
3790                         goto error;
3791         }
3792
3793         if (file) {
3794                 /* read access is always possible with a mapping */
3795                 u32 av = FILE__READ;
3796
3797                 /* write access only matters if the mapping is shared */
3798                 if (shared && (prot & PROT_WRITE))
3799                         av |= FILE__WRITE;
3800
3801                 if (prot & PROT_EXEC)
3802                         av |= FILE__EXECUTE;
3803
3804                 return file_has_perm(cred, file, av);
3805         }
3806
3807 error:
3808         return rc;
3809 }
3810
3811 static int selinux_mmap_addr(unsigned long addr)
3812 {
3813         int rc = 0;
3814
3815         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3816                 u32 sid = current_sid();
3817                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3818                                   MEMPROTECT__MMAP_ZERO, NULL);
3819         }
3820
3821         return rc;
3822 }
3823
3824 static int selinux_mmap_file(struct file *file,
3825                              unsigned long reqprot __always_unused,
3826                              unsigned long prot, unsigned long flags)
3827 {
3828         struct common_audit_data ad;
3829         int rc;
3830
3831         if (file) {
3832                 ad.type = LSM_AUDIT_DATA_FILE;
3833                 ad.u.file = file;
3834                 rc = inode_has_perm(current_cred(), file_inode(file),
3835                                     FILE__MAP, &ad);
3836                 if (rc)
3837                         return rc;
3838         }
3839
3840         return file_map_prot_check(file, prot,
3841                                    (flags & MAP_TYPE) == MAP_SHARED);
3842 }
3843
3844 static int selinux_file_mprotect(struct vm_area_struct *vma,
3845                                  unsigned long reqprot __always_unused,
3846                                  unsigned long prot)
3847 {
3848         const struct cred *cred = current_cred();
3849         u32 sid = cred_sid(cred);
3850
3851         if (default_noexec &&
3852             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3853                 int rc = 0;
3854                 if (vma_is_initial_heap(vma)) {
3855                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3856                                           PROCESS__EXECHEAP, NULL);
3857                 } else if (!vma->vm_file && (vma_is_initial_stack(vma) ||
3858                             vma_is_stack_for_current(vma))) {
3859                         rc = avc_has_perm(sid, sid, SECCLASS_PROCESS,
3860                                           PROCESS__EXECSTACK, NULL);
3861                 } else if (vma->vm_file && vma->anon_vma) {
3862                         /*
3863                          * We are making executable a file mapping that has
3864                          * had some COW done. Since pages might have been
3865                          * written, check ability to execute the possibly
3866                          * modified content.  This typically should only
3867                          * occur for text relocations.
3868                          */
3869                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3870                 }
3871                 if (rc)
3872                         return rc;
3873         }
3874
3875         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3876 }
3877
3878 static int selinux_file_lock(struct file *file, unsigned int cmd)
3879 {
3880         const struct cred *cred = current_cred();
3881
3882         return file_has_perm(cred, file, FILE__LOCK);
3883 }
3884
3885 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3886                               unsigned long arg)
3887 {
3888         const struct cred *cred = current_cred();
3889         int err = 0;
3890
3891         switch (cmd) {
3892         case F_SETFL:
3893                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3894                         err = file_has_perm(cred, file, FILE__WRITE);
3895                         break;
3896                 }
3897                 fallthrough;
3898         case F_SETOWN:
3899         case F_SETSIG:
3900         case F_GETFL:
3901         case F_GETOWN:
3902         case F_GETSIG:
3903         case F_GETOWNER_UIDS:
3904                 /* Just check FD__USE permission */
3905                 err = file_has_perm(cred, file, 0);
3906                 break;
3907         case F_GETLK:
3908         case F_SETLK:
3909         case F_SETLKW:
3910         case F_OFD_GETLK:
3911         case F_OFD_SETLK:
3912         case F_OFD_SETLKW:
3913 #if BITS_PER_LONG == 32
3914         case F_GETLK64:
3915         case F_SETLK64:
3916         case F_SETLKW64:
3917 #endif
3918                 err = file_has_perm(cred, file, FILE__LOCK);
3919                 break;
3920         }
3921
3922         return err;
3923 }
3924
3925 static void selinux_file_set_fowner(struct file *file)
3926 {
3927         struct file_security_struct *fsec;
3928
3929         fsec = selinux_file(file);
3930         fsec->fown_sid = current_sid();
3931 }
3932
3933 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3934                                        struct fown_struct *fown, int signum)
3935 {
3936         struct file *file;
3937         u32 sid = task_sid_obj(tsk);
3938         u32 perm;
3939         struct file_security_struct *fsec;
3940
3941         /* struct fown_struct is never outside the context of a struct file */
3942         file = container_of(fown, struct file, f_owner);
3943
3944         fsec = selinux_file(file);
3945
3946         if (!signum)
3947                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3948         else
3949                 perm = signal_to_av(signum);
3950
3951         return avc_has_perm(fsec->fown_sid, sid,
3952                             SECCLASS_PROCESS, perm, NULL);
3953 }
3954
3955 static int selinux_file_receive(struct file *file)
3956 {
3957         const struct cred *cred = current_cred();
3958
3959         return file_has_perm(cred, file, file_to_av(file));
3960 }
3961
3962 static int selinux_file_open(struct file *file)
3963 {
3964         struct file_security_struct *fsec;
3965         struct inode_security_struct *isec;
3966
3967         fsec = selinux_file(file);
3968         isec = inode_security(file_inode(file));
3969         /*
3970          * Save inode label and policy sequence number
3971          * at open-time so that selinux_file_permission
3972          * can determine whether revalidation is necessary.
3973          * Task label is already saved in the file security
3974          * struct as its SID.
3975          */
3976         fsec->isid = isec->sid;
3977         fsec->pseqno = avc_policy_seqno();
3978         /*
3979          * Since the inode label or policy seqno may have changed
3980          * between the selinux_inode_permission check and the saving
3981          * of state above, recheck that access is still permitted.
3982          * Otherwise, access might never be revalidated against the
3983          * new inode label or new policy.
3984          * This check is not redundant - do not remove.
3985          */
3986         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3987 }
3988
3989 /* task security operations */
3990
3991 static int selinux_task_alloc(struct task_struct *task,
3992                               unsigned long clone_flags)
3993 {
3994         u32 sid = current_sid();
3995
3996         return avc_has_perm(sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3997 }
3998
3999 /*
4000  * prepare a new set of credentials for modification
4001  */
4002 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
4003                                 gfp_t gfp)
4004 {
4005         const struct task_security_struct *old_tsec = selinux_cred(old);
4006         struct task_security_struct *tsec = selinux_cred(new);
4007
4008         *tsec = *old_tsec;
4009         return 0;
4010 }
4011
4012 /*
4013  * transfer the SELinux data to a blank set of creds
4014  */
4015 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
4016 {
4017         const struct task_security_struct *old_tsec = selinux_cred(old);
4018         struct task_security_struct *tsec = selinux_cred(new);
4019
4020         *tsec = *old_tsec;
4021 }
4022
4023 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
4024 {
4025         *secid = cred_sid(c);
4026 }
4027
4028 /*
4029  * set the security data for a kernel service
4030  * - all the creation contexts are set to unlabelled
4031  */
4032 static int selinux_kernel_act_as(struct cred *new, u32 secid)
4033 {
4034         struct task_security_struct *tsec = selinux_cred(new);
4035         u32 sid = current_sid();
4036         int ret;
4037
4038         ret = avc_has_perm(sid, secid,
4039                            SECCLASS_KERNEL_SERVICE,
4040                            KERNEL_SERVICE__USE_AS_OVERRIDE,
4041                            NULL);
4042         if (ret == 0) {
4043                 tsec->sid = secid;
4044                 tsec->create_sid = 0;
4045                 tsec->keycreate_sid = 0;
4046                 tsec->sockcreate_sid = 0;
4047         }
4048         return ret;
4049 }
4050
4051 /*
4052  * set the file creation context in a security record to the same as the
4053  * objective context of the specified inode
4054  */
4055 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
4056 {
4057         struct inode_security_struct *isec = inode_security(inode);
4058         struct task_security_struct *tsec = selinux_cred(new);
4059         u32 sid = current_sid();
4060         int ret;
4061
4062         ret = avc_has_perm(sid, isec->sid,
4063                            SECCLASS_KERNEL_SERVICE,
4064                            KERNEL_SERVICE__CREATE_FILES_AS,
4065                            NULL);
4066
4067         if (ret == 0)
4068                 tsec->create_sid = isec->sid;
4069         return ret;
4070 }
4071
4072 static int selinux_kernel_module_request(char *kmod_name)
4073 {
4074         struct common_audit_data ad;
4075
4076         ad.type = LSM_AUDIT_DATA_KMOD;
4077         ad.u.kmod_name = kmod_name;
4078
4079         return avc_has_perm(current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
4080                             SYSTEM__MODULE_REQUEST, &ad);
4081 }
4082
4083 static int selinux_kernel_module_from_file(struct file *file)
4084 {
4085         struct common_audit_data ad;
4086         struct inode_security_struct *isec;
4087         struct file_security_struct *fsec;
4088         u32 sid = current_sid();
4089         int rc;
4090
4091         /* init_module */
4092         if (file == NULL)
4093                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
4094                                         SYSTEM__MODULE_LOAD, NULL);
4095
4096         /* finit_module */
4097
4098         ad.type = LSM_AUDIT_DATA_FILE;
4099         ad.u.file = file;
4100
4101         fsec = selinux_file(file);
4102         if (sid != fsec->sid) {
4103                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
4104                 if (rc)
4105                         return rc;
4106         }
4107
4108         isec = inode_security(file_inode(file));
4109         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
4110                                 SYSTEM__MODULE_LOAD, &ad);
4111 }
4112
4113 static int selinux_kernel_read_file(struct file *file,
4114                                     enum kernel_read_file_id id,
4115                                     bool contents)
4116 {
4117         int rc = 0;
4118
4119         switch (id) {
4120         case READING_MODULE:
4121                 rc = selinux_kernel_module_from_file(contents ? file : NULL);
4122                 break;
4123         default:
4124                 break;
4125         }
4126
4127         return rc;
4128 }
4129
4130 static int selinux_kernel_load_data(enum kernel_load_data_id id, bool contents)
4131 {
4132         int rc = 0;
4133
4134         switch (id) {
4135         case LOADING_MODULE:
4136                 rc = selinux_kernel_module_from_file(NULL);
4137                 break;
4138         default:
4139                 break;
4140         }
4141
4142         return rc;
4143 }
4144
4145 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4146 {
4147         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4148                             PROCESS__SETPGID, NULL);
4149 }
4150
4151 static int selinux_task_getpgid(struct task_struct *p)
4152 {
4153         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4154                             PROCESS__GETPGID, NULL);
4155 }
4156
4157 static int selinux_task_getsid(struct task_struct *p)
4158 {
4159         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4160                             PROCESS__GETSESSION, NULL);
4161 }
4162
4163 static void selinux_current_getsecid_subj(u32 *secid)
4164 {
4165         *secid = current_sid();
4166 }
4167
4168 static void selinux_task_getsecid_obj(struct task_struct *p, u32 *secid)
4169 {
4170         *secid = task_sid_obj(p);
4171 }
4172
4173 static int selinux_task_setnice(struct task_struct *p, int nice)
4174 {
4175         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4176                             PROCESS__SETSCHED, NULL);
4177 }
4178
4179 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4180 {
4181         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4182                             PROCESS__SETSCHED, NULL);
4183 }
4184
4185 static int selinux_task_getioprio(struct task_struct *p)
4186 {
4187         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4188                             PROCESS__GETSCHED, NULL);
4189 }
4190
4191 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4192                                 unsigned int flags)
4193 {
4194         u32 av = 0;
4195
4196         if (!flags)
4197                 return 0;
4198         if (flags & LSM_PRLIMIT_WRITE)
4199                 av |= PROCESS__SETRLIMIT;
4200         if (flags & LSM_PRLIMIT_READ)
4201                 av |= PROCESS__GETRLIMIT;
4202         return avc_has_perm(cred_sid(cred), cred_sid(tcred),
4203                             SECCLASS_PROCESS, av, NULL);
4204 }
4205
4206 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4207                 struct rlimit *new_rlim)
4208 {
4209         struct rlimit *old_rlim = p->signal->rlim + resource;
4210
4211         /* Control the ability to change the hard limit (whether
4212            lowering or raising it), so that the hard limit can
4213            later be used as a safe reset point for the soft limit
4214            upon context transitions.  See selinux_bprm_committing_creds. */
4215         if (old_rlim->rlim_max != new_rlim->rlim_max)
4216                 return avc_has_perm(current_sid(), task_sid_obj(p),
4217                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4218
4219         return 0;
4220 }
4221
4222 static int selinux_task_setscheduler(struct task_struct *p)
4223 {
4224         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4225                             PROCESS__SETSCHED, NULL);
4226 }
4227
4228 static int selinux_task_getscheduler(struct task_struct *p)
4229 {
4230         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4231                             PROCESS__GETSCHED, NULL);
4232 }
4233
4234 static int selinux_task_movememory(struct task_struct *p)
4235 {
4236         return avc_has_perm(current_sid(), task_sid_obj(p), SECCLASS_PROCESS,
4237                             PROCESS__SETSCHED, NULL);
4238 }
4239
4240 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4241                                 int sig, const struct cred *cred)
4242 {
4243         u32 secid;
4244         u32 perm;
4245
4246         if (!sig)
4247                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4248         else
4249                 perm = signal_to_av(sig);
4250         if (!cred)
4251                 secid = current_sid();
4252         else
4253                 secid = cred_sid(cred);
4254         return avc_has_perm(secid, task_sid_obj(p), SECCLASS_PROCESS, perm, NULL);
4255 }
4256
4257 static void selinux_task_to_inode(struct task_struct *p,
4258                                   struct inode *inode)
4259 {
4260         struct inode_security_struct *isec = selinux_inode(inode);
4261         u32 sid = task_sid_obj(p);
4262
4263         spin_lock(&isec->lock);
4264         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4265         isec->sid = sid;
4266         isec->initialized = LABEL_INITIALIZED;
4267         spin_unlock(&isec->lock);
4268 }
4269
4270 static int selinux_userns_create(const struct cred *cred)
4271 {
4272         u32 sid = current_sid();
4273
4274         return avc_has_perm(sid, sid, SECCLASS_USER_NAMESPACE,
4275                         USER_NAMESPACE__CREATE, NULL);
4276 }
4277
4278 /* Returns error only if unable to parse addresses */
4279 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4280                         struct common_audit_data *ad, u8 *proto)
4281 {
4282         int offset, ihlen, ret = -EINVAL;
4283         struct iphdr _iph, *ih;
4284
4285         offset = skb_network_offset(skb);
4286         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4287         if (ih == NULL)
4288                 goto out;
4289
4290         ihlen = ih->ihl * 4;
4291         if (ihlen < sizeof(_iph))
4292                 goto out;
4293
4294         ad->u.net->v4info.saddr = ih->saddr;
4295         ad->u.net->v4info.daddr = ih->daddr;
4296         ret = 0;
4297
4298         if (proto)
4299                 *proto = ih->protocol;
4300
4301         switch (ih->protocol) {
4302         case IPPROTO_TCP: {
4303                 struct tcphdr _tcph, *th;
4304
4305                 if (ntohs(ih->frag_off) & IP_OFFSET)
4306                         break;
4307
4308                 offset += ihlen;
4309                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4310                 if (th == NULL)
4311                         break;
4312
4313                 ad->u.net->sport = th->source;
4314                 ad->u.net->dport = th->dest;
4315                 break;
4316         }
4317
4318         case IPPROTO_UDP: {
4319                 struct udphdr _udph, *uh;
4320
4321                 if (ntohs(ih->frag_off) & IP_OFFSET)
4322                         break;
4323
4324                 offset += ihlen;
4325                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4326                 if (uh == NULL)
4327                         break;
4328
4329                 ad->u.net->sport = uh->source;
4330                 ad->u.net->dport = uh->dest;
4331                 break;
4332         }
4333
4334         case IPPROTO_DCCP: {
4335                 struct dccp_hdr _dccph, *dh;
4336
4337                 if (ntohs(ih->frag_off) & IP_OFFSET)
4338                         break;
4339
4340                 offset += ihlen;
4341                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4342                 if (dh == NULL)
4343                         break;
4344
4345                 ad->u.net->sport = dh->dccph_sport;
4346                 ad->u.net->dport = dh->dccph_dport;
4347                 break;
4348         }
4349
4350 #if IS_ENABLED(CONFIG_IP_SCTP)
4351         case IPPROTO_SCTP: {
4352                 struct sctphdr _sctph, *sh;
4353
4354                 if (ntohs(ih->frag_off) & IP_OFFSET)
4355                         break;
4356
4357                 offset += ihlen;
4358                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4359                 if (sh == NULL)
4360                         break;
4361
4362                 ad->u.net->sport = sh->source;
4363                 ad->u.net->dport = sh->dest;
4364                 break;
4365         }
4366 #endif
4367         default:
4368                 break;
4369         }
4370 out:
4371         return ret;
4372 }
4373
4374 #if IS_ENABLED(CONFIG_IPV6)
4375
4376 /* Returns error only if unable to parse addresses */
4377 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4378                         struct common_audit_data *ad, u8 *proto)
4379 {
4380         u8 nexthdr;
4381         int ret = -EINVAL, offset;
4382         struct ipv6hdr _ipv6h, *ip6;
4383         __be16 frag_off;
4384
4385         offset = skb_network_offset(skb);
4386         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4387         if (ip6 == NULL)
4388                 goto out;
4389
4390         ad->u.net->v6info.saddr = ip6->saddr;
4391         ad->u.net->v6info.daddr = ip6->daddr;
4392         ret = 0;
4393
4394         nexthdr = ip6->nexthdr;
4395         offset += sizeof(_ipv6h);
4396         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4397         if (offset < 0)
4398                 goto out;
4399
4400         if (proto)
4401                 *proto = nexthdr;
4402
4403         switch (nexthdr) {
4404         case IPPROTO_TCP: {
4405                 struct tcphdr _tcph, *th;
4406
4407                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4408                 if (th == NULL)
4409                         break;
4410
4411                 ad->u.net->sport = th->source;
4412                 ad->u.net->dport = th->dest;
4413                 break;
4414         }
4415
4416         case IPPROTO_UDP: {
4417                 struct udphdr _udph, *uh;
4418
4419                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4420                 if (uh == NULL)
4421                         break;
4422
4423                 ad->u.net->sport = uh->source;
4424                 ad->u.net->dport = uh->dest;
4425                 break;
4426         }
4427
4428         case IPPROTO_DCCP: {
4429                 struct dccp_hdr _dccph, *dh;
4430
4431                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4432                 if (dh == NULL)
4433                         break;
4434
4435                 ad->u.net->sport = dh->dccph_sport;
4436                 ad->u.net->dport = dh->dccph_dport;
4437                 break;
4438         }
4439
4440 #if IS_ENABLED(CONFIG_IP_SCTP)
4441         case IPPROTO_SCTP: {
4442                 struct sctphdr _sctph, *sh;
4443
4444                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4445                 if (sh == NULL)
4446                         break;
4447
4448                 ad->u.net->sport = sh->source;
4449                 ad->u.net->dport = sh->dest;
4450                 break;
4451         }
4452 #endif
4453         /* includes fragments */
4454         default:
4455                 break;
4456         }
4457 out:
4458         return ret;
4459 }
4460
4461 #endif /* IPV6 */
4462
4463 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4464                              char **_addrp, int src, u8 *proto)
4465 {
4466         char *addrp;
4467         int ret;
4468
4469         switch (ad->u.net->family) {
4470         case PF_INET:
4471                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4472                 if (ret)
4473                         goto parse_error;
4474                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4475                                        &ad->u.net->v4info.daddr);
4476                 goto okay;
4477
4478 #if IS_ENABLED(CONFIG_IPV6)
4479         case PF_INET6:
4480                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4481                 if (ret)
4482                         goto parse_error;
4483                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4484                                        &ad->u.net->v6info.daddr);
4485                 goto okay;
4486 #endif  /* IPV6 */
4487         default:
4488                 addrp = NULL;
4489                 goto okay;
4490         }
4491
4492 parse_error:
4493         pr_warn(
4494                "SELinux: failure in selinux_parse_skb(),"
4495                " unable to parse packet\n");
4496         return ret;
4497
4498 okay:
4499         if (_addrp)
4500                 *_addrp = addrp;
4501         return 0;
4502 }
4503
4504 /**
4505  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4506  * @skb: the packet
4507  * @family: protocol family
4508  * @sid: the packet's peer label SID
4509  *
4510  * Description:
4511  * Check the various different forms of network peer labeling and determine
4512  * the peer label/SID for the packet; most of the magic actually occurs in
4513  * the security server function security_net_peersid_cmp().  The function
4514  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4515  * or -EACCES if @sid is invalid due to inconsistencies with the different
4516  * peer labels.
4517  *
4518  */
4519 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4520 {
4521         int err;
4522         u32 xfrm_sid;
4523         u32 nlbl_sid;
4524         u32 nlbl_type;
4525
4526         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4527         if (unlikely(err))
4528                 return -EACCES;
4529         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4530         if (unlikely(err))
4531                 return -EACCES;
4532
4533         err = security_net_peersid_resolve(nlbl_sid,
4534                                            nlbl_type, xfrm_sid, sid);
4535         if (unlikely(err)) {
4536                 pr_warn(
4537                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4538                        " unable to determine packet's peer label\n");
4539                 return -EACCES;
4540         }
4541
4542         return 0;
4543 }
4544
4545 /**
4546  * selinux_conn_sid - Determine the child socket label for a connection
4547  * @sk_sid: the parent socket's SID
4548  * @skb_sid: the packet's SID
4549  * @conn_sid: the resulting connection SID
4550  *
4551  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4552  * combined with the MLS information from @skb_sid in order to create
4553  * @conn_sid.  If @skb_sid is not valid then @conn_sid is simply a copy
4554  * of @sk_sid.  Returns zero on success, negative values on failure.
4555  *
4556  */
4557 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4558 {
4559         int err = 0;
4560
4561         if (skb_sid != SECSID_NULL)
4562                 err = security_sid_mls_copy(sk_sid, skb_sid,
4563                                             conn_sid);
4564         else
4565                 *conn_sid = sk_sid;
4566
4567         return err;
4568 }
4569
4570 /* socket security operations */
4571
4572 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4573                                  u16 secclass, u32 *socksid)
4574 {
4575         if (tsec->sockcreate_sid > SECSID_NULL) {
4576                 *socksid = tsec->sockcreate_sid;
4577                 return 0;
4578         }
4579
4580         return security_transition_sid(tsec->sid, tsec->sid,
4581                                        secclass, NULL, socksid);
4582 }
4583
4584 static int sock_has_perm(struct sock *sk, u32 perms)
4585 {
4586         struct sk_security_struct *sksec = sk->sk_security;
4587         struct common_audit_data ad;
4588         struct lsm_network_audit net;
4589
4590         if (sksec->sid == SECINITSID_KERNEL)
4591                 return 0;
4592
4593         /*
4594          * Before POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT, sockets that
4595          * inherited the kernel context from early boot used to be skipped
4596          * here, so preserve that behavior unless the capability is set.
4597          *
4598          * By setting the capability the policy signals that it is ready
4599          * for this quirk to be fixed. Note that sockets created by a kernel
4600          * thread or a usermode helper executed without a transition will
4601          * still be skipped in this check regardless of the policycap
4602          * setting.
4603          */
4604         if (!selinux_policycap_userspace_initial_context() &&
4605             sksec->sid == SECINITSID_INIT)
4606                 return 0;
4607
4608         ad_net_init_from_sk(&ad, &net, sk);
4609
4610         return avc_has_perm(current_sid(), sksec->sid, sksec->sclass, perms,
4611                             &ad);
4612 }
4613
4614 static int selinux_socket_create(int family, int type,
4615                                  int protocol, int kern)
4616 {
4617         const struct task_security_struct *tsec = selinux_cred(current_cred());
4618         u32 newsid;
4619         u16 secclass;
4620         int rc;
4621
4622         if (kern)
4623                 return 0;
4624
4625         secclass = socket_type_to_security_class(family, type, protocol);
4626         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4627         if (rc)
4628                 return rc;
4629
4630         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4631 }
4632
4633 static int selinux_socket_post_create(struct socket *sock, int family,
4634                                       int type, int protocol, int kern)
4635 {
4636         const struct task_security_struct *tsec = selinux_cred(current_cred());
4637         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4638         struct sk_security_struct *sksec;
4639         u16 sclass = socket_type_to_security_class(family, type, protocol);
4640         u32 sid = SECINITSID_KERNEL;
4641         int err = 0;
4642
4643         if (!kern) {
4644                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4645                 if (err)
4646                         return err;
4647         }
4648
4649         isec->sclass = sclass;
4650         isec->sid = sid;
4651         isec->initialized = LABEL_INITIALIZED;
4652
4653         if (sock->sk) {
4654                 sksec = sock->sk->sk_security;
4655                 sksec->sclass = sclass;
4656                 sksec->sid = sid;
4657                 /* Allows detection of the first association on this socket */
4658                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4659                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4660
4661                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4662         }
4663
4664         return err;
4665 }
4666
4667 static int selinux_socket_socketpair(struct socket *socka,
4668                                      struct socket *sockb)
4669 {
4670         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4671         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4672
4673         sksec_a->peer_sid = sksec_b->sid;
4674         sksec_b->peer_sid = sksec_a->sid;
4675
4676         return 0;
4677 }
4678
4679 /* Range of port numbers used to automatically bind.
4680    Need to determine whether we should perform a name_bind
4681    permission check between the socket and the port number. */
4682
4683 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4684 {
4685         struct sock *sk = sock->sk;
4686         struct sk_security_struct *sksec = sk->sk_security;
4687         u16 family;
4688         int err;
4689
4690         err = sock_has_perm(sk, SOCKET__BIND);
4691         if (err)
4692                 goto out;
4693
4694         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4695         family = sk->sk_family;
4696         if (family == PF_INET || family == PF_INET6) {
4697                 char *addrp;
4698                 struct common_audit_data ad;
4699                 struct lsm_network_audit net = {0,};
4700                 struct sockaddr_in *addr4 = NULL;
4701                 struct sockaddr_in6 *addr6 = NULL;
4702                 u16 family_sa;
4703                 unsigned short snum;
4704                 u32 sid, node_perm;
4705
4706                 /*
4707                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4708                  * that validates multiple binding addresses. Because of this
4709                  * need to check address->sa_family as it is possible to have
4710                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4711                  */
4712                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4713                         return -EINVAL;
4714                 family_sa = address->sa_family;
4715                 switch (family_sa) {
4716                 case AF_UNSPEC:
4717                 case AF_INET:
4718                         if (addrlen < sizeof(struct sockaddr_in))
4719                                 return -EINVAL;
4720                         addr4 = (struct sockaddr_in *)address;
4721                         if (family_sa == AF_UNSPEC) {
4722                                 if (family == PF_INET6) {
4723                                         /* Length check from inet6_bind_sk() */
4724                                         if (addrlen < SIN6_LEN_RFC2133)
4725                                                 return -EINVAL;
4726                                         /* Family check from __inet6_bind() */
4727                                         goto err_af;
4728                                 }
4729                                 /* see __inet_bind(), we only want to allow
4730                                  * AF_UNSPEC if the address is INADDR_ANY
4731                                  */
4732                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4733                                         goto err_af;
4734                                 family_sa = AF_INET;
4735                         }
4736                         snum = ntohs(addr4->sin_port);
4737                         addrp = (char *)&addr4->sin_addr.s_addr;
4738                         break;
4739                 case AF_INET6:
4740                         if (addrlen < SIN6_LEN_RFC2133)
4741                                 return -EINVAL;
4742                         addr6 = (struct sockaddr_in6 *)address;
4743                         snum = ntohs(addr6->sin6_port);
4744                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4745                         break;
4746                 default:
4747                         goto err_af;
4748                 }
4749
4750                 ad.type = LSM_AUDIT_DATA_NET;
4751                 ad.u.net = &net;
4752                 ad.u.net->sport = htons(snum);
4753                 ad.u.net->family = family_sa;
4754
4755                 if (snum) {
4756                         int low, high;
4757
4758                         inet_get_local_port_range(sock_net(sk), &low, &high);
4759
4760                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4761                             snum < low || snum > high) {
4762                                 err = sel_netport_sid(sk->sk_protocol,
4763                                                       snum, &sid);
4764                                 if (err)
4765                                         goto out;
4766                                 err = avc_has_perm(sksec->sid, sid,
4767                                                    sksec->sclass,
4768                                                    SOCKET__NAME_BIND, &ad);
4769                                 if (err)
4770                                         goto out;
4771                         }
4772                 }
4773
4774                 switch (sksec->sclass) {
4775                 case SECCLASS_TCP_SOCKET:
4776                         node_perm = TCP_SOCKET__NODE_BIND;
4777                         break;
4778
4779                 case SECCLASS_UDP_SOCKET:
4780                         node_perm = UDP_SOCKET__NODE_BIND;
4781                         break;
4782
4783                 case SECCLASS_DCCP_SOCKET:
4784                         node_perm = DCCP_SOCKET__NODE_BIND;
4785                         break;
4786
4787                 case SECCLASS_SCTP_SOCKET:
4788                         node_perm = SCTP_SOCKET__NODE_BIND;
4789                         break;
4790
4791                 default:
4792                         node_perm = RAWIP_SOCKET__NODE_BIND;
4793                         break;
4794                 }
4795
4796                 err = sel_netnode_sid(addrp, family_sa, &sid);
4797                 if (err)
4798                         goto out;
4799
4800                 if (family_sa == AF_INET)
4801                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4802                 else
4803                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4804
4805                 err = avc_has_perm(sksec->sid, sid,
4806                                    sksec->sclass, node_perm, &ad);
4807                 if (err)
4808                         goto out;
4809         }
4810 out:
4811         return err;
4812 err_af:
4813         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4814         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4815                 return -EINVAL;
4816         return -EAFNOSUPPORT;
4817 }
4818
4819 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4820  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4821  */
4822 static int selinux_socket_connect_helper(struct socket *sock,
4823                                          struct sockaddr *address, int addrlen)
4824 {
4825         struct sock *sk = sock->sk;
4826         struct sk_security_struct *sksec = sk->sk_security;
4827         int err;
4828
4829         err = sock_has_perm(sk, SOCKET__CONNECT);
4830         if (err)
4831                 return err;
4832         if (addrlen < offsetofend(struct sockaddr, sa_family))
4833                 return -EINVAL;
4834
4835         /* connect(AF_UNSPEC) has special handling, as it is a documented
4836          * way to disconnect the socket
4837          */
4838         if (address->sa_family == AF_UNSPEC)
4839                 return 0;
4840
4841         /*
4842          * If a TCP, DCCP or SCTP socket, check name_connect permission
4843          * for the port.
4844          */
4845         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4846             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4847             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4848                 struct common_audit_data ad;
4849                 struct lsm_network_audit net = {0,};
4850                 struct sockaddr_in *addr4 = NULL;
4851                 struct sockaddr_in6 *addr6 = NULL;
4852                 unsigned short snum;
4853                 u32 sid, perm;
4854
4855                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4856                  * that validates multiple connect addresses. Because of this
4857                  * need to check address->sa_family as it is possible to have
4858                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4859                  */
4860                 switch (address->sa_family) {
4861                 case AF_INET:
4862                         addr4 = (struct sockaddr_in *)address;
4863                         if (addrlen < sizeof(struct sockaddr_in))
4864                                 return -EINVAL;
4865                         snum = ntohs(addr4->sin_port);
4866                         break;
4867                 case AF_INET6:
4868                         addr6 = (struct sockaddr_in6 *)address;
4869                         if (addrlen < SIN6_LEN_RFC2133)
4870                                 return -EINVAL;
4871                         snum = ntohs(addr6->sin6_port);
4872                         break;
4873                 default:
4874                         /* Note that SCTP services expect -EINVAL, whereas
4875                          * others expect -EAFNOSUPPORT.
4876                          */
4877                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4878                                 return -EINVAL;
4879                         else
4880                                 return -EAFNOSUPPORT;
4881                 }
4882
4883                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4884                 if (err)
4885                         return err;
4886
4887                 switch (sksec->sclass) {
4888                 case SECCLASS_TCP_SOCKET:
4889                         perm = TCP_SOCKET__NAME_CONNECT;
4890                         break;
4891                 case SECCLASS_DCCP_SOCKET:
4892                         perm = DCCP_SOCKET__NAME_CONNECT;
4893                         break;
4894                 case SECCLASS_SCTP_SOCKET:
4895                         perm = SCTP_SOCKET__NAME_CONNECT;
4896                         break;
4897                 }
4898
4899                 ad.type = LSM_AUDIT_DATA_NET;
4900                 ad.u.net = &net;
4901                 ad.u.net->dport = htons(snum);
4902                 ad.u.net->family = address->sa_family;
4903                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4904                 if (err)
4905                         return err;
4906         }
4907
4908         return 0;
4909 }
4910
4911 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4912 static int selinux_socket_connect(struct socket *sock,
4913                                   struct sockaddr *address, int addrlen)
4914 {
4915         int err;
4916         struct sock *sk = sock->sk;
4917
4918         err = selinux_socket_connect_helper(sock, address, addrlen);
4919         if (err)
4920                 return err;
4921
4922         return selinux_netlbl_socket_connect(sk, address);
4923 }
4924
4925 static int selinux_socket_listen(struct socket *sock, int backlog)
4926 {
4927         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4928 }
4929
4930 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4931 {
4932         int err;
4933         struct inode_security_struct *isec;
4934         struct inode_security_struct *newisec;
4935         u16 sclass;
4936         u32 sid;
4937
4938         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4939         if (err)
4940                 return err;
4941
4942         isec = inode_security_novalidate(SOCK_INODE(sock));
4943         spin_lock(&isec->lock);
4944         sclass = isec->sclass;
4945         sid = isec->sid;
4946         spin_unlock(&isec->lock);
4947
4948         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4949         newisec->sclass = sclass;
4950         newisec->sid = sid;
4951         newisec->initialized = LABEL_INITIALIZED;
4952
4953         return 0;
4954 }
4955
4956 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4957                                   int size)
4958 {
4959         return sock_has_perm(sock->sk, SOCKET__WRITE);
4960 }
4961
4962 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4963                                   int size, int flags)
4964 {
4965         return sock_has_perm(sock->sk, SOCKET__READ);
4966 }
4967
4968 static int selinux_socket_getsockname(struct socket *sock)
4969 {
4970         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4971 }
4972
4973 static int selinux_socket_getpeername(struct socket *sock)
4974 {
4975         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4976 }
4977
4978 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4979 {
4980         int err;
4981
4982         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4983         if (err)
4984                 return err;
4985
4986         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4987 }
4988
4989 static int selinux_socket_getsockopt(struct socket *sock, int level,
4990                                      int optname)
4991 {
4992         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4993 }
4994
4995 static int selinux_socket_shutdown(struct socket *sock, int how)
4996 {
4997         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4998 }
4999
5000 static int selinux_socket_unix_stream_connect(struct sock *sock,
5001                                               struct sock *other,
5002                                               struct sock *newsk)
5003 {
5004         struct sk_security_struct *sksec_sock = sock->sk_security;
5005         struct sk_security_struct *sksec_other = other->sk_security;
5006         struct sk_security_struct *sksec_new = newsk->sk_security;
5007         struct common_audit_data ad;
5008         struct lsm_network_audit net;
5009         int err;
5010
5011         ad_net_init_from_sk(&ad, &net, other);
5012
5013         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
5014                            sksec_other->sclass,
5015                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
5016         if (err)
5017                 return err;
5018
5019         /* server child socket */
5020         sksec_new->peer_sid = sksec_sock->sid;
5021         err = security_sid_mls_copy(sksec_other->sid,
5022                                     sksec_sock->sid, &sksec_new->sid);
5023         if (err)
5024                 return err;
5025
5026         /* connecting socket */
5027         sksec_sock->peer_sid = sksec_new->sid;
5028
5029         return 0;
5030 }
5031
5032 static int selinux_socket_unix_may_send(struct socket *sock,
5033                                         struct socket *other)
5034 {
5035         struct sk_security_struct *ssec = sock->sk->sk_security;
5036         struct sk_security_struct *osec = other->sk->sk_security;
5037         struct common_audit_data ad;
5038         struct lsm_network_audit net;
5039
5040         ad_net_init_from_sk(&ad, &net, other->sk);
5041
5042         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
5043                             &ad);
5044 }
5045
5046 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
5047                                     char *addrp, u16 family, u32 peer_sid,
5048                                     struct common_audit_data *ad)
5049 {
5050         int err;
5051         u32 if_sid;
5052         u32 node_sid;
5053
5054         err = sel_netif_sid(ns, ifindex, &if_sid);
5055         if (err)
5056                 return err;
5057         err = avc_has_perm(peer_sid, if_sid,
5058                            SECCLASS_NETIF, NETIF__INGRESS, ad);
5059         if (err)
5060                 return err;
5061
5062         err = sel_netnode_sid(addrp, family, &node_sid);
5063         if (err)
5064                 return err;
5065         return avc_has_perm(peer_sid, node_sid,
5066                             SECCLASS_NODE, NODE__RECVFROM, ad);
5067 }
5068
5069 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
5070                                        u16 family)
5071 {
5072         int err = 0;
5073         struct sk_security_struct *sksec = sk->sk_security;
5074         u32 sk_sid = sksec->sid;
5075         struct common_audit_data ad;
5076         struct lsm_network_audit net;
5077         char *addrp;
5078
5079         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5080         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5081         if (err)
5082                 return err;
5083
5084         if (selinux_secmark_enabled()) {
5085                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5086                                    PACKET__RECV, &ad);
5087                 if (err)
5088                         return err;
5089         }
5090
5091         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
5092         if (err)
5093                 return err;
5094         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
5095
5096         return err;
5097 }
5098
5099 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
5100 {
5101         int err, peerlbl_active, secmark_active;
5102         struct sk_security_struct *sksec = sk->sk_security;
5103         u16 family = sk->sk_family;
5104         u32 sk_sid = sksec->sid;
5105         struct common_audit_data ad;
5106         struct lsm_network_audit net;
5107         char *addrp;
5108
5109         if (family != PF_INET && family != PF_INET6)
5110                 return 0;
5111
5112         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5113         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5114                 family = PF_INET;
5115
5116         /* If any sort of compatibility mode is enabled then handoff processing
5117          * to the selinux_sock_rcv_skb_compat() function to deal with the
5118          * special handling.  We do this in an attempt to keep this function
5119          * as fast and as clean as possible. */
5120         if (!selinux_policycap_netpeer())
5121                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5122
5123         secmark_active = selinux_secmark_enabled();
5124         peerlbl_active = selinux_peerlbl_enabled();
5125         if (!secmark_active && !peerlbl_active)
5126                 return 0;
5127
5128         ad_net_init_from_iif(&ad, &net, skb->skb_iif, family);
5129         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5130         if (err)
5131                 return err;
5132
5133         if (peerlbl_active) {
5134                 u32 peer_sid;
5135
5136                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5137                 if (err)
5138                         return err;
5139                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5140                                                addrp, family, peer_sid, &ad);
5141                 if (err) {
5142                         selinux_netlbl_err(skb, family, err, 0);
5143                         return err;
5144                 }
5145                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
5146                                    PEER__RECV, &ad);
5147                 if (err) {
5148                         selinux_netlbl_err(skb, family, err, 0);
5149                         return err;
5150                 }
5151         }
5152
5153         if (secmark_active) {
5154                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
5155                                    PACKET__RECV, &ad);
5156                 if (err)
5157                         return err;
5158         }
5159
5160         return err;
5161 }
5162
5163 static int selinux_socket_getpeersec_stream(struct socket *sock,
5164                                             sockptr_t optval, sockptr_t optlen,
5165                                             unsigned int len)
5166 {
5167         int err = 0;
5168         char *scontext = NULL;
5169         u32 scontext_len;
5170         struct sk_security_struct *sksec = sock->sk->sk_security;
5171         u32 peer_sid = SECSID_NULL;
5172
5173         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5174             sksec->sclass == SECCLASS_TCP_SOCKET ||
5175             sksec->sclass == SECCLASS_SCTP_SOCKET)
5176                 peer_sid = sksec->peer_sid;
5177         if (peer_sid == SECSID_NULL)
5178                 return -ENOPROTOOPT;
5179
5180         err = security_sid_to_context(peer_sid, &scontext,
5181                                       &scontext_len);
5182         if (err)
5183                 return err;
5184         if (scontext_len > len) {
5185                 err = -ERANGE;
5186                 goto out_len;
5187         }
5188
5189         if (copy_to_sockptr(optval, scontext, scontext_len))
5190                 err = -EFAULT;
5191 out_len:
5192         if (copy_to_sockptr(optlen, &scontext_len, sizeof(scontext_len)))
5193                 err = -EFAULT;
5194         kfree(scontext);
5195         return err;
5196 }
5197
5198 static int selinux_socket_getpeersec_dgram(struct socket *sock,
5199                                            struct sk_buff *skb, u32 *secid)
5200 {
5201         u32 peer_secid = SECSID_NULL;
5202         u16 family;
5203
5204         if (skb && skb->protocol == htons(ETH_P_IP))
5205                 family = PF_INET;
5206         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5207                 family = PF_INET6;
5208         else if (sock)
5209                 family = sock->sk->sk_family;
5210         else {
5211                 *secid = SECSID_NULL;
5212                 return -EINVAL;
5213         }
5214
5215         if (sock && family == PF_UNIX) {
5216                 struct inode_security_struct *isec;
5217                 isec = inode_security_novalidate(SOCK_INODE(sock));
5218                 peer_secid = isec->sid;
5219         } else if (skb)
5220                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5221
5222         *secid = peer_secid;
5223         if (peer_secid == SECSID_NULL)
5224                 return -ENOPROTOOPT;
5225         return 0;
5226 }
5227
5228 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5229 {
5230         struct sk_security_struct *sksec;
5231
5232         sksec = kzalloc(sizeof(*sksec), priority);
5233         if (!sksec)
5234                 return -ENOMEM;
5235
5236         sksec->peer_sid = SECINITSID_UNLABELED;
5237         sksec->sid = SECINITSID_UNLABELED;
5238         sksec->sclass = SECCLASS_SOCKET;
5239         selinux_netlbl_sk_security_reset(sksec);
5240         sk->sk_security = sksec;
5241
5242         return 0;
5243 }
5244
5245 static void selinux_sk_free_security(struct sock *sk)
5246 {
5247         struct sk_security_struct *sksec = sk->sk_security;
5248
5249         sk->sk_security = NULL;
5250         selinux_netlbl_sk_security_free(sksec);
5251         kfree(sksec);
5252 }
5253
5254 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5255 {
5256         struct sk_security_struct *sksec = sk->sk_security;
5257         struct sk_security_struct *newsksec = newsk->sk_security;
5258
5259         newsksec->sid = sksec->sid;
5260         newsksec->peer_sid = sksec->peer_sid;
5261         newsksec->sclass = sksec->sclass;
5262
5263         selinux_netlbl_sk_security_reset(newsksec);
5264 }
5265
5266 static void selinux_sk_getsecid(const struct sock *sk, u32 *secid)
5267 {
5268         if (!sk)
5269                 *secid = SECINITSID_ANY_SOCKET;
5270         else {
5271                 const struct sk_security_struct *sksec = sk->sk_security;
5272
5273                 *secid = sksec->sid;
5274         }
5275 }
5276
5277 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5278 {
5279         struct inode_security_struct *isec =
5280                 inode_security_novalidate(SOCK_INODE(parent));
5281         struct sk_security_struct *sksec = sk->sk_security;
5282
5283         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5284             sk->sk_family == PF_UNIX)
5285                 isec->sid = sksec->sid;
5286         sksec->sclass = isec->sclass;
5287 }
5288
5289 /*
5290  * Determines peer_secid for the asoc and updates socket's peer label
5291  * if it's the first association on the socket.
5292  */
5293 static int selinux_sctp_process_new_assoc(struct sctp_association *asoc,
5294                                           struct sk_buff *skb)
5295 {
5296         struct sock *sk = asoc->base.sk;
5297         u16 family = sk->sk_family;
5298         struct sk_security_struct *sksec = sk->sk_security;
5299         struct common_audit_data ad;
5300         struct lsm_network_audit net;
5301         int err;
5302
5303         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5304         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5305                 family = PF_INET;
5306
5307         if (selinux_peerlbl_enabled()) {
5308                 asoc->peer_secid = SECSID_NULL;
5309
5310                 /* This will return peer_sid = SECSID_NULL if there are
5311                  * no peer labels, see security_net_peersid_resolve().
5312                  */
5313                 err = selinux_skb_peerlbl_sid(skb, family, &asoc->peer_secid);
5314                 if (err)
5315                         return err;
5316
5317                 if (asoc->peer_secid == SECSID_NULL)
5318                         asoc->peer_secid = SECINITSID_UNLABELED;
5319         } else {
5320                 asoc->peer_secid = SECINITSID_UNLABELED;
5321         }
5322
5323         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5324                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5325
5326                 /* Here as first association on socket. As the peer SID
5327                  * was allowed by peer recv (and the netif/node checks),
5328                  * then it is approved by policy and used as the primary
5329                  * peer SID for getpeercon(3).
5330                  */
5331                 sksec->peer_sid = asoc->peer_secid;
5332         } else if (sksec->peer_sid != asoc->peer_secid) {
5333                 /* Other association peer SIDs are checked to enforce
5334                  * consistency among the peer SIDs.
5335                  */
5336                 ad_net_init_from_sk(&ad, &net, asoc->base.sk);
5337                 err = avc_has_perm(sksec->peer_sid, asoc->peer_secid,
5338                                    sksec->sclass, SCTP_SOCKET__ASSOCIATION,
5339                                    &ad);
5340                 if (err)
5341                         return err;
5342         }
5343         return 0;
5344 }
5345
5346 /* Called whenever SCTP receives an INIT or COOKIE ECHO chunk. This
5347  * happens on an incoming connect(2), sctp_connectx(3) or
5348  * sctp_sendmsg(3) (with no association already present).
5349  */
5350 static int selinux_sctp_assoc_request(struct sctp_association *asoc,
5351                                       struct sk_buff *skb)
5352 {
5353         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5354         u32 conn_sid;
5355         int err;
5356
5357         if (!selinux_policycap_extsockclass())
5358                 return 0;
5359
5360         err = selinux_sctp_process_new_assoc(asoc, skb);
5361         if (err)
5362                 return err;
5363
5364         /* Compute the MLS component for the connection and store
5365          * the information in asoc. This will be used by SCTP TCP type
5366          * sockets and peeled off connections as they cause a new
5367          * socket to be generated. selinux_sctp_sk_clone() will then
5368          * plug this into the new socket.
5369          */
5370         err = selinux_conn_sid(sksec->sid, asoc->peer_secid, &conn_sid);
5371         if (err)
5372                 return err;
5373
5374         asoc->secid = conn_sid;
5375
5376         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5377         return selinux_netlbl_sctp_assoc_request(asoc, skb);
5378 }
5379
5380 /* Called when SCTP receives a COOKIE ACK chunk as the final
5381  * response to an association request (initited by us).
5382  */
5383 static int selinux_sctp_assoc_established(struct sctp_association *asoc,
5384                                           struct sk_buff *skb)
5385 {
5386         struct sk_security_struct *sksec = asoc->base.sk->sk_security;
5387
5388         if (!selinux_policycap_extsockclass())
5389                 return 0;
5390
5391         /* Inherit secid from the parent socket - this will be picked up
5392          * by selinux_sctp_sk_clone() if the association gets peeled off
5393          * into a new socket.
5394          */
5395         asoc->secid = sksec->sid;
5396
5397         return selinux_sctp_process_new_assoc(asoc, skb);
5398 }
5399
5400 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5401  * based on their @optname.
5402  */
5403 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5404                                      struct sockaddr *address,
5405                                      int addrlen)
5406 {
5407         int len, err = 0, walk_size = 0;
5408         void *addr_buf;
5409         struct sockaddr *addr;
5410         struct socket *sock;
5411
5412         if (!selinux_policycap_extsockclass())
5413                 return 0;
5414
5415         /* Process one or more addresses that may be IPv4 or IPv6 */
5416         sock = sk->sk_socket;
5417         addr_buf = address;
5418
5419         while (walk_size < addrlen) {
5420                 if (walk_size + sizeof(sa_family_t) > addrlen)
5421                         return -EINVAL;
5422
5423                 addr = addr_buf;
5424                 switch (addr->sa_family) {
5425                 case AF_UNSPEC:
5426                 case AF_INET:
5427                         len = sizeof(struct sockaddr_in);
5428                         break;
5429                 case AF_INET6:
5430                         len = sizeof(struct sockaddr_in6);
5431                         break;
5432                 default:
5433                         return -EINVAL;
5434                 }
5435
5436                 if (walk_size + len > addrlen)
5437                         return -EINVAL;
5438
5439                 err = -EINVAL;
5440                 switch (optname) {
5441                 /* Bind checks */
5442                 case SCTP_PRIMARY_ADDR:
5443                 case SCTP_SET_PEER_PRIMARY_ADDR:
5444                 case SCTP_SOCKOPT_BINDX_ADD:
5445                         err = selinux_socket_bind(sock, addr, len);
5446                         break;
5447                 /* Connect checks */
5448                 case SCTP_SOCKOPT_CONNECTX:
5449                 case SCTP_PARAM_SET_PRIMARY:
5450                 case SCTP_PARAM_ADD_IP:
5451                 case SCTP_SENDMSG_CONNECT:
5452                         err = selinux_socket_connect_helper(sock, addr, len);
5453                         if (err)
5454                                 return err;
5455
5456                         /* As selinux_sctp_bind_connect() is called by the
5457                          * SCTP protocol layer, the socket is already locked,
5458                          * therefore selinux_netlbl_socket_connect_locked()
5459                          * is called here. The situations handled are:
5460                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5461                          * whenever a new IP address is added or when a new
5462                          * primary address is selected.
5463                          * Note that an SCTP connect(2) call happens before
5464                          * the SCTP protocol layer and is handled via
5465                          * selinux_socket_connect().
5466                          */
5467                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5468                         break;
5469                 }
5470
5471                 if (err)
5472                         return err;
5473
5474                 addr_buf += len;
5475                 walk_size += len;
5476         }
5477
5478         return 0;
5479 }
5480
5481 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5482 static void selinux_sctp_sk_clone(struct sctp_association *asoc, struct sock *sk,
5483                                   struct sock *newsk)
5484 {
5485         struct sk_security_struct *sksec = sk->sk_security;
5486         struct sk_security_struct *newsksec = newsk->sk_security;
5487
5488         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5489          * the non-sctp clone version.
5490          */
5491         if (!selinux_policycap_extsockclass())
5492                 return selinux_sk_clone_security(sk, newsk);
5493
5494         newsksec->sid = asoc->secid;
5495         newsksec->peer_sid = asoc->peer_secid;
5496         newsksec->sclass = sksec->sclass;
5497         selinux_netlbl_sctp_sk_clone(sk, newsk);
5498 }
5499
5500 static int selinux_mptcp_add_subflow(struct sock *sk, struct sock *ssk)
5501 {
5502         struct sk_security_struct *ssksec = ssk->sk_security;
5503         struct sk_security_struct *sksec = sk->sk_security;
5504
5505         ssksec->sclass = sksec->sclass;
5506         ssksec->sid = sksec->sid;
5507
5508         /* replace the existing subflow label deleting the existing one
5509          * and re-recreating a new label using the updated context
5510          */
5511         selinux_netlbl_sk_security_free(ssksec);
5512         return selinux_netlbl_socket_post_create(ssk, ssk->sk_family);
5513 }
5514
5515 static int selinux_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
5516                                      struct request_sock *req)
5517 {
5518         struct sk_security_struct *sksec = sk->sk_security;
5519         int err;
5520         u16 family = req->rsk_ops->family;
5521         u32 connsid;
5522         u32 peersid;
5523
5524         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5525         if (err)
5526                 return err;
5527         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5528         if (err)
5529                 return err;
5530         req->secid = connsid;
5531         req->peer_secid = peersid;
5532
5533         return selinux_netlbl_inet_conn_request(req, family);
5534 }
5535
5536 static void selinux_inet_csk_clone(struct sock *newsk,
5537                                    const struct request_sock *req)
5538 {
5539         struct sk_security_struct *newsksec = newsk->sk_security;
5540
5541         newsksec->sid = req->secid;
5542         newsksec->peer_sid = req->peer_secid;
5543         /* NOTE: Ideally, we should also get the isec->sid for the
5544            new socket in sync, but we don't have the isec available yet.
5545            So we will wait until sock_graft to do it, by which
5546            time it will have been created and available. */
5547
5548         /* We don't need to take any sort of lock here as we are the only
5549          * thread with access to newsksec */
5550         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5551 }
5552
5553 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5554 {
5555         u16 family = sk->sk_family;
5556         struct sk_security_struct *sksec = sk->sk_security;
5557
5558         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5559         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5560                 family = PF_INET;
5561
5562         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5563 }
5564
5565 static int selinux_secmark_relabel_packet(u32 sid)
5566 {
5567         const struct task_security_struct *tsec;
5568         u32 tsid;
5569
5570         tsec = selinux_cred(current_cred());
5571         tsid = tsec->sid;
5572
5573         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5574                             NULL);
5575 }
5576
5577 static void selinux_secmark_refcount_inc(void)
5578 {
5579         atomic_inc(&selinux_secmark_refcount);
5580 }
5581
5582 static void selinux_secmark_refcount_dec(void)
5583 {
5584         atomic_dec(&selinux_secmark_refcount);
5585 }
5586
5587 static void selinux_req_classify_flow(const struct request_sock *req,
5588                                       struct flowi_common *flic)
5589 {
5590         flic->flowic_secid = req->secid;
5591 }
5592
5593 static int selinux_tun_dev_alloc_security(void **security)
5594 {
5595         struct tun_security_struct *tunsec;
5596
5597         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5598         if (!tunsec)
5599                 return -ENOMEM;
5600         tunsec->sid = current_sid();
5601
5602         *security = tunsec;
5603         return 0;
5604 }
5605
5606 static void selinux_tun_dev_free_security(void *security)
5607 {
5608         kfree(security);
5609 }
5610
5611 static int selinux_tun_dev_create(void)
5612 {
5613         u32 sid = current_sid();
5614
5615         /* we aren't taking into account the "sockcreate" SID since the socket
5616          * that is being created here is not a socket in the traditional sense,
5617          * instead it is a private sock, accessible only to the kernel, and
5618          * representing a wide range of network traffic spanning multiple
5619          * connections unlike traditional sockets - check the TUN driver to
5620          * get a better understanding of why this socket is special */
5621
5622         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5623                             NULL);
5624 }
5625
5626 static int selinux_tun_dev_attach_queue(void *security)
5627 {
5628         struct tun_security_struct *tunsec = security;
5629
5630         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5631                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5632 }
5633
5634 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5635 {
5636         struct tun_security_struct *tunsec = security;
5637         struct sk_security_struct *sksec = sk->sk_security;
5638
5639         /* we don't currently perform any NetLabel based labeling here and it
5640          * isn't clear that we would want to do so anyway; while we could apply
5641          * labeling without the support of the TUN user the resulting labeled
5642          * traffic from the other end of the connection would almost certainly
5643          * cause confusion to the TUN user that had no idea network labeling
5644          * protocols were being used */
5645
5646         sksec->sid = tunsec->sid;
5647         sksec->sclass = SECCLASS_TUN_SOCKET;
5648
5649         return 0;
5650 }
5651
5652 static int selinux_tun_dev_open(void *security)
5653 {
5654         struct tun_security_struct *tunsec = security;
5655         u32 sid = current_sid();
5656         int err;
5657
5658         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5659                            TUN_SOCKET__RELABELFROM, NULL);
5660         if (err)
5661                 return err;
5662         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5663                            TUN_SOCKET__RELABELTO, NULL);
5664         if (err)
5665                 return err;
5666         tunsec->sid = sid;
5667
5668         return 0;
5669 }
5670
5671 #ifdef CONFIG_NETFILTER
5672
5673 static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
5674                                        const struct nf_hook_state *state)
5675 {
5676         int ifindex;
5677         u16 family;
5678         char *addrp;
5679         u32 peer_sid;
5680         struct common_audit_data ad;
5681         struct lsm_network_audit net;
5682         int secmark_active, peerlbl_active;
5683
5684         if (!selinux_policycap_netpeer())
5685                 return NF_ACCEPT;
5686
5687         secmark_active = selinux_secmark_enabled();
5688         peerlbl_active = selinux_peerlbl_enabled();
5689         if (!secmark_active && !peerlbl_active)
5690                 return NF_ACCEPT;
5691
5692         family = state->pf;
5693         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5694                 return NF_DROP;
5695
5696         ifindex = state->in->ifindex;
5697         ad_net_init_from_iif(&ad, &net, ifindex, family);
5698         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5699                 return NF_DROP;
5700
5701         if (peerlbl_active) {
5702                 int err;
5703
5704                 err = selinux_inet_sys_rcv_skb(state->net, ifindex,
5705                                                addrp, family, peer_sid, &ad);
5706                 if (err) {
5707                         selinux_netlbl_err(skb, family, err, 1);
5708                         return NF_DROP;
5709                 }
5710         }
5711
5712         if (secmark_active)
5713                 if (avc_has_perm(peer_sid, skb->secmark,
5714                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5715                         return NF_DROP;
5716
5717         if (netlbl_enabled())
5718                 /* we do this in the FORWARD path and not the POST_ROUTING
5719                  * path because we want to make sure we apply the necessary
5720                  * labeling before IPsec is applied so we can leverage AH
5721                  * protection */
5722                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5723                         return NF_DROP;
5724
5725         return NF_ACCEPT;
5726 }
5727
5728 static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
5729                                       const struct nf_hook_state *state)
5730 {
5731         struct sock *sk;
5732         u32 sid;
5733
5734         if (!netlbl_enabled())
5735                 return NF_ACCEPT;
5736
5737         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5738          * because we want to make sure we apply the necessary labeling
5739          * before IPsec is applied so we can leverage AH protection */
5740         sk = skb->sk;
5741         if (sk) {
5742                 struct sk_security_struct *sksec;
5743
5744                 if (sk_listener(sk))
5745                         /* if the socket is the listening state then this
5746                          * packet is a SYN-ACK packet which means it needs to
5747                          * be labeled based on the connection/request_sock and
5748                          * not the parent socket.  unfortunately, we can't
5749                          * lookup the request_sock yet as it isn't queued on
5750                          * the parent socket until after the SYN-ACK is sent.
5751                          * the "solution" is to simply pass the packet as-is
5752                          * as any IP option based labeling should be copied
5753                          * from the initial connection request (in the IP
5754                          * layer).  it is far from ideal, but until we get a
5755                          * security label in the packet itself this is the
5756                          * best we can do. */
5757                         return NF_ACCEPT;
5758
5759                 /* standard practice, label using the parent socket */
5760                 sksec = sk->sk_security;
5761                 sid = sksec->sid;
5762         } else
5763                 sid = SECINITSID_KERNEL;
5764         if (selinux_netlbl_skbuff_setsid(skb, state->pf, sid) != 0)
5765                 return NF_DROP;
5766
5767         return NF_ACCEPT;
5768 }
5769
5770
5771 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5772                                         const struct nf_hook_state *state)
5773 {
5774         struct sock *sk;
5775         struct sk_security_struct *sksec;
5776         struct common_audit_data ad;
5777         struct lsm_network_audit net;
5778         u8 proto = 0;
5779
5780         sk = skb_to_full_sk(skb);
5781         if (sk == NULL)
5782                 return NF_ACCEPT;
5783         sksec = sk->sk_security;
5784
5785         ad_net_init_from_iif(&ad, &net, state->out->ifindex, state->pf);
5786         if (selinux_parse_skb(skb, &ad, NULL, 0, &proto))
5787                 return NF_DROP;
5788
5789         if (selinux_secmark_enabled())
5790                 if (avc_has_perm(sksec->sid, skb->secmark,
5791                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5792                         return NF_DROP_ERR(-ECONNREFUSED);
5793
5794         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5795                 return NF_DROP_ERR(-ECONNREFUSED);
5796
5797         return NF_ACCEPT;
5798 }
5799
5800 static unsigned int selinux_ip_postroute(void *priv,
5801                                          struct sk_buff *skb,
5802                                          const struct nf_hook_state *state)
5803 {
5804         u16 family;
5805         u32 secmark_perm;
5806         u32 peer_sid;
5807         int ifindex;
5808         struct sock *sk;
5809         struct common_audit_data ad;
5810         struct lsm_network_audit net;
5811         char *addrp;
5812         int secmark_active, peerlbl_active;
5813
5814         /* If any sort of compatibility mode is enabled then handoff processing
5815          * to the selinux_ip_postroute_compat() function to deal with the
5816          * special handling.  We do this in an attempt to keep this function
5817          * as fast and as clean as possible. */
5818         if (!selinux_policycap_netpeer())
5819                 return selinux_ip_postroute_compat(skb, state);
5820
5821         secmark_active = selinux_secmark_enabled();
5822         peerlbl_active = selinux_peerlbl_enabled();
5823         if (!secmark_active && !peerlbl_active)
5824                 return NF_ACCEPT;
5825
5826         sk = skb_to_full_sk(skb);
5827
5828 #ifdef CONFIG_XFRM
5829         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5830          * packet transformation so allow the packet to pass without any checks
5831          * since we'll have another chance to perform access control checks
5832          * when the packet is on it's final way out.
5833          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5834          *       is NULL, in this case go ahead and apply access control.
5835          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5836          *       TCP listening state we cannot wait until the XFRM processing
5837          *       is done as we will miss out on the SA label if we do;
5838          *       unfortunately, this means more work, but it is only once per
5839          *       connection. */
5840         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5841             !(sk && sk_listener(sk)))
5842                 return NF_ACCEPT;
5843 #endif
5844
5845         family = state->pf;
5846         if (sk == NULL) {
5847                 /* Without an associated socket the packet is either coming
5848                  * from the kernel or it is being forwarded; check the packet
5849                  * to determine which and if the packet is being forwarded
5850                  * query the packet directly to determine the security label. */
5851                 if (skb->skb_iif) {
5852                         secmark_perm = PACKET__FORWARD_OUT;
5853                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5854                                 return NF_DROP;
5855                 } else {
5856                         secmark_perm = PACKET__SEND;
5857                         peer_sid = SECINITSID_KERNEL;
5858                 }
5859         } else if (sk_listener(sk)) {
5860                 /* Locally generated packet but the associated socket is in the
5861                  * listening state which means this is a SYN-ACK packet.  In
5862                  * this particular case the correct security label is assigned
5863                  * to the connection/request_sock but unfortunately we can't
5864                  * query the request_sock as it isn't queued on the parent
5865                  * socket until after the SYN-ACK packet is sent; the only
5866                  * viable choice is to regenerate the label like we do in
5867                  * selinux_inet_conn_request().  See also selinux_ip_output()
5868                  * for similar problems. */
5869                 u32 skb_sid;
5870                 struct sk_security_struct *sksec;
5871
5872                 sksec = sk->sk_security;
5873                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5874                         return NF_DROP;
5875                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5876                  * and the packet has been through at least one XFRM
5877                  * transformation then we must be dealing with the "final"
5878                  * form of labeled IPsec packet; since we've already applied
5879                  * all of our access controls on this packet we can safely
5880                  * pass the packet. */
5881                 if (skb_sid == SECSID_NULL) {
5882                         switch (family) {
5883                         case PF_INET:
5884                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5885                                         return NF_ACCEPT;
5886                                 break;
5887                         case PF_INET6:
5888                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5889                                         return NF_ACCEPT;
5890                                 break;
5891                         default:
5892                                 return NF_DROP_ERR(-ECONNREFUSED);
5893                         }
5894                 }
5895                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5896                         return NF_DROP;
5897                 secmark_perm = PACKET__SEND;
5898         } else {
5899                 /* Locally generated packet, fetch the security label from the
5900                  * associated socket. */
5901                 struct sk_security_struct *sksec = sk->sk_security;
5902                 peer_sid = sksec->sid;
5903                 secmark_perm = PACKET__SEND;
5904         }
5905
5906         ifindex = state->out->ifindex;
5907         ad_net_init_from_iif(&ad, &net, ifindex, family);
5908         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5909                 return NF_DROP;
5910
5911         if (secmark_active)
5912                 if (avc_has_perm(peer_sid, skb->secmark,
5913                                  SECCLASS_PACKET, secmark_perm, &ad))
5914                         return NF_DROP_ERR(-ECONNREFUSED);
5915
5916         if (peerlbl_active) {
5917                 u32 if_sid;
5918                 u32 node_sid;
5919
5920                 if (sel_netif_sid(state->net, ifindex, &if_sid))
5921                         return NF_DROP;
5922                 if (avc_has_perm(peer_sid, if_sid,
5923                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5924                         return NF_DROP_ERR(-ECONNREFUSED);
5925
5926                 if (sel_netnode_sid(addrp, family, &node_sid))
5927                         return NF_DROP;
5928                 if (avc_has_perm(peer_sid, node_sid,
5929                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5930                         return NF_DROP_ERR(-ECONNREFUSED);
5931         }
5932
5933         return NF_ACCEPT;
5934 }
5935 #endif  /* CONFIG_NETFILTER */
5936
5937 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5938 {
5939         int rc = 0;
5940         unsigned int msg_len;
5941         unsigned int data_len = skb->len;
5942         unsigned char *data = skb->data;
5943         struct nlmsghdr *nlh;
5944         struct sk_security_struct *sksec = sk->sk_security;
5945         u16 sclass = sksec->sclass;
5946         u32 perm;
5947
5948         while (data_len >= nlmsg_total_size(0)) {
5949                 nlh = (struct nlmsghdr *)data;
5950
5951                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5952                  *       users which means we can't reject skb's with bogus
5953                  *       length fields; our solution is to follow what
5954                  *       netlink_rcv_skb() does and simply skip processing at
5955                  *       messages with length fields that are clearly junk
5956                  */
5957                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5958                         return 0;
5959
5960                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5961                 if (rc == 0) {
5962                         rc = sock_has_perm(sk, perm);
5963                         if (rc)
5964                                 return rc;
5965                 } else if (rc == -EINVAL) {
5966                         /* -EINVAL is a missing msg/perm mapping */
5967                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5968                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5969                                 " pid=%d comm=%s\n",
5970                                 sk->sk_protocol, nlh->nlmsg_type,
5971                                 secclass_map[sclass - 1].name,
5972                                 task_pid_nr(current), current->comm);
5973                         if (enforcing_enabled() &&
5974                             !security_get_allow_unknown())
5975                                 return rc;
5976                         rc = 0;
5977                 } else if (rc == -ENOENT) {
5978                         /* -ENOENT is a missing socket/class mapping, ignore */
5979                         rc = 0;
5980                 } else {
5981                         return rc;
5982                 }
5983
5984                 /* move to the next message after applying netlink padding */
5985                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5986                 if (msg_len >= data_len)
5987                         return 0;
5988                 data_len -= msg_len;
5989                 data += msg_len;
5990         }
5991
5992         return rc;
5993 }
5994
5995 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5996 {
5997         isec->sclass = sclass;
5998         isec->sid = current_sid();
5999 }
6000
6001 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
6002                         u32 perms)
6003 {
6004         struct ipc_security_struct *isec;
6005         struct common_audit_data ad;
6006         u32 sid = current_sid();
6007
6008         isec = selinux_ipc(ipc_perms);
6009
6010         ad.type = LSM_AUDIT_DATA_IPC;
6011         ad.u.ipc_id = ipc_perms->key;
6012
6013         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
6014 }
6015
6016 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
6017 {
6018         struct msg_security_struct *msec;
6019
6020         msec = selinux_msg_msg(msg);
6021         msec->sid = SECINITSID_UNLABELED;
6022
6023         return 0;
6024 }
6025
6026 /* message queue security operations */
6027 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
6028 {
6029         struct ipc_security_struct *isec;
6030         struct common_audit_data ad;
6031         u32 sid = current_sid();
6032
6033         isec = selinux_ipc(msq);
6034         ipc_init_security(isec, SECCLASS_MSGQ);
6035
6036         ad.type = LSM_AUDIT_DATA_IPC;
6037         ad.u.ipc_id = msq->key;
6038
6039         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6040                             MSGQ__CREATE, &ad);
6041 }
6042
6043 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
6044 {
6045         struct ipc_security_struct *isec;
6046         struct common_audit_data ad;
6047         u32 sid = current_sid();
6048
6049         isec = selinux_ipc(msq);
6050
6051         ad.type = LSM_AUDIT_DATA_IPC;
6052         ad.u.ipc_id = msq->key;
6053
6054         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6055                             MSGQ__ASSOCIATE, &ad);
6056 }
6057
6058 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
6059 {
6060         u32 perms;
6061
6062         switch (cmd) {
6063         case IPC_INFO:
6064         case MSG_INFO:
6065                 /* No specific object, just general system-wide information. */
6066                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6067                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6068         case IPC_STAT:
6069         case MSG_STAT:
6070         case MSG_STAT_ANY:
6071                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
6072                 break;
6073         case IPC_SET:
6074                 perms = MSGQ__SETATTR;
6075                 break;
6076         case IPC_RMID:
6077                 perms = MSGQ__DESTROY;
6078                 break;
6079         default:
6080                 return 0;
6081         }
6082
6083         return ipc_has_perm(msq, perms);
6084 }
6085
6086 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
6087 {
6088         struct ipc_security_struct *isec;
6089         struct msg_security_struct *msec;
6090         struct common_audit_data ad;
6091         u32 sid = current_sid();
6092         int rc;
6093
6094         isec = selinux_ipc(msq);
6095         msec = selinux_msg_msg(msg);
6096
6097         /*
6098          * First time through, need to assign label to the message
6099          */
6100         if (msec->sid == SECINITSID_UNLABELED) {
6101                 /*
6102                  * Compute new sid based on current process and
6103                  * message queue this message will be stored in
6104                  */
6105                 rc = security_transition_sid(sid, isec->sid,
6106                                              SECCLASS_MSG, NULL, &msec->sid);
6107                 if (rc)
6108                         return rc;
6109         }
6110
6111         ad.type = LSM_AUDIT_DATA_IPC;
6112         ad.u.ipc_id = msq->key;
6113
6114         /* Can this process write to the queue? */
6115         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
6116                           MSGQ__WRITE, &ad);
6117         if (!rc)
6118                 /* Can this process send the message */
6119                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
6120                                   MSG__SEND, &ad);
6121         if (!rc)
6122                 /* Can the message be put in the queue? */
6123                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
6124                                   MSGQ__ENQUEUE, &ad);
6125
6126         return rc;
6127 }
6128
6129 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6130                                     struct task_struct *target,
6131                                     long type, int mode)
6132 {
6133         struct ipc_security_struct *isec;
6134         struct msg_security_struct *msec;
6135         struct common_audit_data ad;
6136         u32 sid = task_sid_obj(target);
6137         int rc;
6138
6139         isec = selinux_ipc(msq);
6140         msec = selinux_msg_msg(msg);
6141
6142         ad.type = LSM_AUDIT_DATA_IPC;
6143         ad.u.ipc_id = msq->key;
6144
6145         rc = avc_has_perm(sid, isec->sid,
6146                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6147         if (!rc)
6148                 rc = avc_has_perm(sid, msec->sid,
6149                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6150         return rc;
6151 }
6152
6153 /* Shared Memory security operations */
6154 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6155 {
6156         struct ipc_security_struct *isec;
6157         struct common_audit_data ad;
6158         u32 sid = current_sid();
6159
6160         isec = selinux_ipc(shp);
6161         ipc_init_security(isec, SECCLASS_SHM);
6162
6163         ad.type = LSM_AUDIT_DATA_IPC;
6164         ad.u.ipc_id = shp->key;
6165
6166         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6167                             SHM__CREATE, &ad);
6168 }
6169
6170 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6171 {
6172         struct ipc_security_struct *isec;
6173         struct common_audit_data ad;
6174         u32 sid = current_sid();
6175
6176         isec = selinux_ipc(shp);
6177
6178         ad.type = LSM_AUDIT_DATA_IPC;
6179         ad.u.ipc_id = shp->key;
6180
6181         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
6182                             SHM__ASSOCIATE, &ad);
6183 }
6184
6185 /* Note, at this point, shp is locked down */
6186 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6187 {
6188         u32 perms;
6189
6190         switch (cmd) {
6191         case IPC_INFO:
6192         case SHM_INFO:
6193                 /* No specific object, just general system-wide information. */
6194                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6195                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6196         case IPC_STAT:
6197         case SHM_STAT:
6198         case SHM_STAT_ANY:
6199                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6200                 break;
6201         case IPC_SET:
6202                 perms = SHM__SETATTR;
6203                 break;
6204         case SHM_LOCK:
6205         case SHM_UNLOCK:
6206                 perms = SHM__LOCK;
6207                 break;
6208         case IPC_RMID:
6209                 perms = SHM__DESTROY;
6210                 break;
6211         default:
6212                 return 0;
6213         }
6214
6215         return ipc_has_perm(shp, perms);
6216 }
6217
6218 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6219                              char __user *shmaddr, int shmflg)
6220 {
6221         u32 perms;
6222
6223         if (shmflg & SHM_RDONLY)
6224                 perms = SHM__READ;
6225         else
6226                 perms = SHM__READ | SHM__WRITE;
6227
6228         return ipc_has_perm(shp, perms);
6229 }
6230
6231 /* Semaphore security operations */
6232 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6233 {
6234         struct ipc_security_struct *isec;
6235         struct common_audit_data ad;
6236         u32 sid = current_sid();
6237
6238         isec = selinux_ipc(sma);
6239         ipc_init_security(isec, SECCLASS_SEM);
6240
6241         ad.type = LSM_AUDIT_DATA_IPC;
6242         ad.u.ipc_id = sma->key;
6243
6244         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6245                             SEM__CREATE, &ad);
6246 }
6247
6248 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6249 {
6250         struct ipc_security_struct *isec;
6251         struct common_audit_data ad;
6252         u32 sid = current_sid();
6253
6254         isec = selinux_ipc(sma);
6255
6256         ad.type = LSM_AUDIT_DATA_IPC;
6257         ad.u.ipc_id = sma->key;
6258
6259         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
6260                             SEM__ASSOCIATE, &ad);
6261 }
6262
6263 /* Note, at this point, sma is locked down */
6264 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6265 {
6266         int err;
6267         u32 perms;
6268
6269         switch (cmd) {
6270         case IPC_INFO:
6271         case SEM_INFO:
6272                 /* No specific object, just general system-wide information. */
6273                 return avc_has_perm(current_sid(), SECINITSID_KERNEL,
6274                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6275         case GETPID:
6276         case GETNCNT:
6277         case GETZCNT:
6278                 perms = SEM__GETATTR;
6279                 break;
6280         case GETVAL:
6281         case GETALL:
6282                 perms = SEM__READ;
6283                 break;
6284         case SETVAL:
6285         case SETALL:
6286                 perms = SEM__WRITE;
6287                 break;
6288         case IPC_RMID:
6289                 perms = SEM__DESTROY;
6290                 break;
6291         case IPC_SET:
6292                 perms = SEM__SETATTR;
6293                 break;
6294         case IPC_STAT:
6295         case SEM_STAT:
6296         case SEM_STAT_ANY:
6297                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6298                 break;
6299         default:
6300                 return 0;
6301         }
6302
6303         err = ipc_has_perm(sma, perms);
6304         return err;
6305 }
6306
6307 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6308                              struct sembuf *sops, unsigned nsops, int alter)
6309 {
6310         u32 perms;
6311
6312         if (alter)
6313                 perms = SEM__READ | SEM__WRITE;
6314         else
6315                 perms = SEM__READ;
6316
6317         return ipc_has_perm(sma, perms);
6318 }
6319
6320 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6321 {
6322         u32 av = 0;
6323
6324         av = 0;
6325         if (flag & S_IRUGO)
6326                 av |= IPC__UNIX_READ;
6327         if (flag & S_IWUGO)
6328                 av |= IPC__UNIX_WRITE;
6329
6330         if (av == 0)
6331                 return 0;
6332
6333         return ipc_has_perm(ipcp, av);
6334 }
6335
6336 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6337 {
6338         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6339         *secid = isec->sid;
6340 }
6341
6342 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6343 {
6344         if (inode)
6345                 inode_doinit_with_dentry(inode, dentry);
6346 }
6347
6348 static int selinux_lsm_getattr(unsigned int attr, struct task_struct *p,
6349                                char **value)
6350 {
6351         const struct task_security_struct *__tsec;
6352         u32 sid;
6353         int error;
6354         unsigned len;
6355
6356         rcu_read_lock();
6357         __tsec = selinux_cred(__task_cred(p));
6358
6359         if (current != p) {
6360                 error = avc_has_perm(current_sid(), __tsec->sid,
6361                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6362                 if (error)
6363                         goto bad;
6364         }
6365
6366         switch (attr) {
6367         case LSM_ATTR_CURRENT:
6368                 sid = __tsec->sid;
6369                 break;
6370         case LSM_ATTR_PREV:
6371                 sid = __tsec->osid;
6372                 break;
6373         case LSM_ATTR_EXEC:
6374                 sid = __tsec->exec_sid;
6375                 break;
6376         case LSM_ATTR_FSCREATE:
6377                 sid = __tsec->create_sid;
6378                 break;
6379         case LSM_ATTR_KEYCREATE:
6380                 sid = __tsec->keycreate_sid;
6381                 break;
6382         case LSM_ATTR_SOCKCREATE:
6383                 sid = __tsec->sockcreate_sid;
6384                 break;
6385         default:
6386                 error = -EOPNOTSUPP;
6387                 goto bad;
6388         }
6389         rcu_read_unlock();
6390
6391         if (!sid)
6392                 return 0;
6393
6394         error = security_sid_to_context(sid, value, &len);
6395         if (error)
6396                 return error;
6397         return len;
6398
6399 bad:
6400         rcu_read_unlock();
6401         return error;
6402 }
6403
6404 static int selinux_lsm_setattr(u64 attr, void *value, size_t size)
6405 {
6406         struct task_security_struct *tsec;
6407         struct cred *new;
6408         u32 mysid = current_sid(), sid = 0, ptsid;
6409         int error;
6410         char *str = value;
6411
6412         /*
6413          * Basic control over ability to set these attributes at all.
6414          */
6415         switch (attr) {
6416         case LSM_ATTR_EXEC:
6417                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6418                                      PROCESS__SETEXEC, NULL);
6419                 break;
6420         case LSM_ATTR_FSCREATE:
6421                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6422                                      PROCESS__SETFSCREATE, NULL);
6423                 break;
6424         case LSM_ATTR_KEYCREATE:
6425                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6426                                      PROCESS__SETKEYCREATE, NULL);
6427                 break;
6428         case LSM_ATTR_SOCKCREATE:
6429                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6430                                      PROCESS__SETSOCKCREATE, NULL);
6431                 break;
6432         case LSM_ATTR_CURRENT:
6433                 error = avc_has_perm(mysid, mysid, SECCLASS_PROCESS,
6434                                      PROCESS__SETCURRENT, NULL);
6435                 break;
6436         default:
6437                 error = -EOPNOTSUPP;
6438                 break;
6439         }
6440         if (error)
6441                 return error;
6442
6443         /* Obtain a SID for the context, if one was specified. */
6444         if (size && str[0] && str[0] != '\n') {
6445                 if (str[size-1] == '\n') {
6446                         str[size-1] = 0;
6447                         size--;
6448                 }
6449                 error = security_context_to_sid(value, size,
6450                                                 &sid, GFP_KERNEL);
6451                 if (error == -EINVAL && attr == LSM_ATTR_FSCREATE) {
6452                         if (!has_cap_mac_admin(true)) {
6453                                 struct audit_buffer *ab;
6454                                 size_t audit_size;
6455
6456                                 /* We strip a nul only if it is at the end,
6457                                  * otherwise the context contains a nul and
6458                                  * we should audit that */
6459                                 if (str[size - 1] == '\0')
6460                                         audit_size = size - 1;
6461                                 else
6462                                         audit_size = size;
6463                                 ab = audit_log_start(audit_context(),
6464                                                      GFP_ATOMIC,
6465                                                      AUDIT_SELINUX_ERR);
6466                                 if (!ab)
6467                                         return error;
6468                                 audit_log_format(ab, "op=fscreate invalid_context=");
6469                                 audit_log_n_untrustedstring(ab, value,
6470                                                             audit_size);
6471                                 audit_log_end(ab);
6472
6473                                 return error;
6474                         }
6475                         error = security_context_to_sid_force(value, size,
6476                                                         &sid);
6477                 }
6478                 if (error)
6479                         return error;
6480         }
6481
6482         new = prepare_creds();
6483         if (!new)
6484                 return -ENOMEM;
6485
6486         /* Permission checking based on the specified context is
6487            performed during the actual operation (execve,
6488            open/mkdir/...), when we know the full context of the
6489            operation.  See selinux_bprm_creds_for_exec for the execve
6490            checks and may_create for the file creation checks. The
6491            operation will then fail if the context is not permitted. */
6492         tsec = selinux_cred(new);
6493         if (attr == LSM_ATTR_EXEC) {
6494                 tsec->exec_sid = sid;
6495         } else if (attr == LSM_ATTR_FSCREATE) {
6496                 tsec->create_sid = sid;
6497         } else if (attr == LSM_ATTR_KEYCREATE) {
6498                 if (sid) {
6499                         error = avc_has_perm(mysid, sid,
6500                                              SECCLASS_KEY, KEY__CREATE, NULL);
6501                         if (error)
6502                                 goto abort_change;
6503                 }
6504                 tsec->keycreate_sid = sid;
6505         } else if (attr == LSM_ATTR_SOCKCREATE) {
6506                 tsec->sockcreate_sid = sid;
6507         } else if (attr == LSM_ATTR_CURRENT) {
6508                 error = -EINVAL;
6509                 if (sid == 0)
6510                         goto abort_change;
6511
6512                 if (!current_is_single_threaded()) {
6513                         error = security_bounded_transition(tsec->sid, sid);
6514                         if (error)
6515                                 goto abort_change;
6516                 }
6517
6518                 /* Check permissions for the transition. */
6519                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
6520                                      PROCESS__DYNTRANSITION, NULL);
6521                 if (error)
6522                         goto abort_change;
6523
6524                 /* Check for ptracing, and update the task SID if ok.
6525                    Otherwise, leave SID unchanged and fail. */
6526                 ptsid = ptrace_parent_sid();
6527                 if (ptsid != 0) {
6528                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
6529                                              PROCESS__PTRACE, NULL);
6530                         if (error)
6531                                 goto abort_change;
6532                 }
6533
6534                 tsec->sid = sid;
6535         } else {
6536                 error = -EINVAL;
6537                 goto abort_change;
6538         }
6539
6540         commit_creds(new);
6541         return size;
6542
6543 abort_change:
6544         abort_creds(new);
6545         return error;
6546 }
6547
6548 /**
6549  * selinux_getselfattr - Get SELinux current task attributes
6550  * @attr: the requested attribute
6551  * @ctx: buffer to receive the result
6552  * @size: buffer size (input), buffer size used (output)
6553  * @flags: unused
6554  *
6555  * Fill the passed user space @ctx with the details of the requested
6556  * attribute.
6557  *
6558  * Returns the number of attributes on success, an error code otherwise.
6559  * There will only ever be one attribute.
6560  */
6561 static int selinux_getselfattr(unsigned int attr, struct lsm_ctx __user *ctx,
6562                                u32 *size, u32 flags)
6563 {
6564         int rc;
6565         char *val = NULL;
6566         int val_len;
6567
6568         val_len = selinux_lsm_getattr(attr, current, &val);
6569         if (val_len < 0)
6570                 return val_len;
6571         rc = lsm_fill_user_ctx(ctx, size, val, val_len, LSM_ID_SELINUX, 0);
6572         kfree(val);
6573         return (!rc ? 1 : rc);
6574 }
6575
6576 static int selinux_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
6577                                u32 size, u32 flags)
6578 {
6579         int rc;
6580
6581         rc = selinux_lsm_setattr(attr, ctx->ctx, ctx->ctx_len);
6582         if (rc > 0)
6583                 return 0;
6584         return rc;
6585 }
6586
6587 static int selinux_getprocattr(struct task_struct *p,
6588                                const char *name, char **value)
6589 {
6590         unsigned int attr = lsm_name_to_attr(name);
6591         int rc;
6592
6593         if (attr) {
6594                 rc = selinux_lsm_getattr(attr, p, value);
6595                 if (rc != -EOPNOTSUPP)
6596                         return rc;
6597         }
6598
6599         return -EINVAL;
6600 }
6601
6602 static int selinux_setprocattr(const char *name, void *value, size_t size)
6603 {
6604         int attr = lsm_name_to_attr(name);
6605
6606         if (attr)
6607                 return selinux_lsm_setattr(attr, value, size);
6608         return -EINVAL;
6609 }
6610
6611 static int selinux_ismaclabel(const char *name)
6612 {
6613         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6614 }
6615
6616 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6617 {
6618         return security_sid_to_context(secid,
6619                                        secdata, seclen);
6620 }
6621
6622 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6623 {
6624         return security_context_to_sid(secdata, seclen,
6625                                        secid, GFP_KERNEL);
6626 }
6627
6628 static void selinux_release_secctx(char *secdata, u32 seclen)
6629 {
6630         kfree(secdata);
6631 }
6632
6633 static void selinux_inode_invalidate_secctx(struct inode *inode)
6634 {
6635         struct inode_security_struct *isec = selinux_inode(inode);
6636
6637         spin_lock(&isec->lock);
6638         isec->initialized = LABEL_INVALID;
6639         spin_unlock(&isec->lock);
6640 }
6641
6642 /*
6643  *      called with inode->i_mutex locked
6644  */
6645 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6646 {
6647         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6648                                            ctx, ctxlen, 0);
6649         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6650         return rc == -EOPNOTSUPP ? 0 : rc;
6651 }
6652
6653 /*
6654  *      called with inode->i_mutex locked
6655  */
6656 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6657 {
6658         return __vfs_setxattr_noperm(&nop_mnt_idmap, dentry, XATTR_NAME_SELINUX,
6659                                      ctx, ctxlen, 0);
6660 }
6661
6662 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6663 {
6664         int len = 0;
6665         len = selinux_inode_getsecurity(&nop_mnt_idmap, inode,
6666                                         XATTR_SELINUX_SUFFIX, ctx, true);
6667         if (len < 0)
6668                 return len;
6669         *ctxlen = len;
6670         return 0;
6671 }
6672 #ifdef CONFIG_KEYS
6673
6674 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6675                              unsigned long flags)
6676 {
6677         const struct task_security_struct *tsec;
6678         struct key_security_struct *ksec;
6679
6680         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6681         if (!ksec)
6682                 return -ENOMEM;
6683
6684         tsec = selinux_cred(cred);
6685         if (tsec->keycreate_sid)
6686                 ksec->sid = tsec->keycreate_sid;
6687         else
6688                 ksec->sid = tsec->sid;
6689
6690         k->security = ksec;
6691         return 0;
6692 }
6693
6694 static void selinux_key_free(struct key *k)
6695 {
6696         struct key_security_struct *ksec = k->security;
6697
6698         k->security = NULL;
6699         kfree(ksec);
6700 }
6701
6702 static int selinux_key_permission(key_ref_t key_ref,
6703                                   const struct cred *cred,
6704                                   enum key_need_perm need_perm)
6705 {
6706         struct key *key;
6707         struct key_security_struct *ksec;
6708         u32 perm, sid;
6709
6710         switch (need_perm) {
6711         case KEY_NEED_VIEW:
6712                 perm = KEY__VIEW;
6713                 break;
6714         case KEY_NEED_READ:
6715                 perm = KEY__READ;
6716                 break;
6717         case KEY_NEED_WRITE:
6718                 perm = KEY__WRITE;
6719                 break;
6720         case KEY_NEED_SEARCH:
6721                 perm = KEY__SEARCH;
6722                 break;
6723         case KEY_NEED_LINK:
6724                 perm = KEY__LINK;
6725                 break;
6726         case KEY_NEED_SETATTR:
6727                 perm = KEY__SETATTR;
6728                 break;
6729         case KEY_NEED_UNLINK:
6730         case KEY_SYSADMIN_OVERRIDE:
6731         case KEY_AUTHTOKEN_OVERRIDE:
6732         case KEY_DEFER_PERM_CHECK:
6733                 return 0;
6734         default:
6735                 WARN_ON(1);
6736                 return -EPERM;
6737
6738         }
6739
6740         sid = cred_sid(cred);
6741         key = key_ref_to_ptr(key_ref);
6742         ksec = key->security;
6743
6744         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6745 }
6746
6747 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6748 {
6749         struct key_security_struct *ksec = key->security;
6750         char *context = NULL;
6751         unsigned len;
6752         int rc;
6753
6754         rc = security_sid_to_context(ksec->sid,
6755                                      &context, &len);
6756         if (!rc)
6757                 rc = len;
6758         *_buffer = context;
6759         return rc;
6760 }
6761
6762 #ifdef CONFIG_KEY_NOTIFICATIONS
6763 static int selinux_watch_key(struct key *key)
6764 {
6765         struct key_security_struct *ksec = key->security;
6766         u32 sid = current_sid();
6767
6768         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6769 }
6770 #endif
6771 #endif
6772
6773 #ifdef CONFIG_SECURITY_INFINIBAND
6774 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6775 {
6776         struct common_audit_data ad;
6777         int err;
6778         u32 sid = 0;
6779         struct ib_security_struct *sec = ib_sec;
6780         struct lsm_ibpkey_audit ibpkey;
6781
6782         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6783         if (err)
6784                 return err;
6785
6786         ad.type = LSM_AUDIT_DATA_IBPKEY;
6787         ibpkey.subnet_prefix = subnet_prefix;
6788         ibpkey.pkey = pkey_val;
6789         ad.u.ibpkey = &ibpkey;
6790         return avc_has_perm(sec->sid, sid,
6791                             SECCLASS_INFINIBAND_PKEY,
6792                             INFINIBAND_PKEY__ACCESS, &ad);
6793 }
6794
6795 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6796                                             u8 port_num)
6797 {
6798         struct common_audit_data ad;
6799         int err;
6800         u32 sid = 0;
6801         struct ib_security_struct *sec = ib_sec;
6802         struct lsm_ibendport_audit ibendport;
6803
6804         err = security_ib_endport_sid(dev_name, port_num,
6805                                       &sid);
6806
6807         if (err)
6808                 return err;
6809
6810         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6811         ibendport.dev_name = dev_name;
6812         ibendport.port = port_num;
6813         ad.u.ibendport = &ibendport;
6814         return avc_has_perm(sec->sid, sid,
6815                             SECCLASS_INFINIBAND_ENDPORT,
6816                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6817 }
6818
6819 static int selinux_ib_alloc_security(void **ib_sec)
6820 {
6821         struct ib_security_struct *sec;
6822
6823         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6824         if (!sec)
6825                 return -ENOMEM;
6826         sec->sid = current_sid();
6827
6828         *ib_sec = sec;
6829         return 0;
6830 }
6831
6832 static void selinux_ib_free_security(void *ib_sec)
6833 {
6834         kfree(ib_sec);
6835 }
6836 #endif
6837
6838 #ifdef CONFIG_BPF_SYSCALL
6839 static int selinux_bpf(int cmd, union bpf_attr *attr,
6840                                      unsigned int size)
6841 {
6842         u32 sid = current_sid();
6843         int ret;
6844
6845         switch (cmd) {
6846         case BPF_MAP_CREATE:
6847                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6848                                    NULL);
6849                 break;
6850         case BPF_PROG_LOAD:
6851                 ret = avc_has_perm(sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6852                                    NULL);
6853                 break;
6854         default:
6855                 ret = 0;
6856                 break;
6857         }
6858
6859         return ret;
6860 }
6861
6862 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6863 {
6864         u32 av = 0;
6865
6866         if (fmode & FMODE_READ)
6867                 av |= BPF__MAP_READ;
6868         if (fmode & FMODE_WRITE)
6869                 av |= BPF__MAP_WRITE;
6870         return av;
6871 }
6872
6873 /* This function will check the file pass through unix socket or binder to see
6874  * if it is a bpf related object. And apply corresponding checks on the bpf
6875  * object based on the type. The bpf maps and programs, not like other files and
6876  * socket, are using a shared anonymous inode inside the kernel as their inode.
6877  * So checking that inode cannot identify if the process have privilege to
6878  * access the bpf object and that's why we have to add this additional check in
6879  * selinux_file_receive and selinux_binder_transfer_files.
6880  */
6881 static int bpf_fd_pass(const struct file *file, u32 sid)
6882 {
6883         struct bpf_security_struct *bpfsec;
6884         struct bpf_prog *prog;
6885         struct bpf_map *map;
6886         int ret;
6887
6888         if (file->f_op == &bpf_map_fops) {
6889                 map = file->private_data;
6890                 bpfsec = map->security;
6891                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6892                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6893                 if (ret)
6894                         return ret;
6895         } else if (file->f_op == &bpf_prog_fops) {
6896                 prog = file->private_data;
6897                 bpfsec = prog->aux->security;
6898                 ret = avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6899                                    BPF__PROG_RUN, NULL);
6900                 if (ret)
6901                         return ret;
6902         }
6903         return 0;
6904 }
6905
6906 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6907 {
6908         u32 sid = current_sid();
6909         struct bpf_security_struct *bpfsec;
6910
6911         bpfsec = map->security;
6912         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6913                             bpf_map_fmode_to_av(fmode), NULL);
6914 }
6915
6916 static int selinux_bpf_prog(struct bpf_prog *prog)
6917 {
6918         u32 sid = current_sid();
6919         struct bpf_security_struct *bpfsec;
6920
6921         bpfsec = prog->aux->security;
6922         return avc_has_perm(sid, bpfsec->sid, SECCLASS_BPF,
6923                             BPF__PROG_RUN, NULL);
6924 }
6925
6926 static int selinux_bpf_map_create(struct bpf_map *map, union bpf_attr *attr,
6927                                   struct bpf_token *token)
6928 {
6929         struct bpf_security_struct *bpfsec;
6930
6931         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6932         if (!bpfsec)
6933                 return -ENOMEM;
6934
6935         bpfsec->sid = current_sid();
6936         map->security = bpfsec;
6937
6938         return 0;
6939 }
6940
6941 static void selinux_bpf_map_free(struct bpf_map *map)
6942 {
6943         struct bpf_security_struct *bpfsec = map->security;
6944
6945         map->security = NULL;
6946         kfree(bpfsec);
6947 }
6948
6949 static int selinux_bpf_prog_load(struct bpf_prog *prog, union bpf_attr *attr,
6950                                  struct bpf_token *token)
6951 {
6952         struct bpf_security_struct *bpfsec;
6953
6954         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6955         if (!bpfsec)
6956                 return -ENOMEM;
6957
6958         bpfsec->sid = current_sid();
6959         prog->aux->security = bpfsec;
6960
6961         return 0;
6962 }
6963
6964 static void selinux_bpf_prog_free(struct bpf_prog *prog)
6965 {
6966         struct bpf_security_struct *bpfsec = prog->aux->security;
6967
6968         prog->aux->security = NULL;
6969         kfree(bpfsec);
6970 }
6971
6972 static int selinux_bpf_token_create(struct bpf_token *token, union bpf_attr *attr,
6973                                     struct path *path)
6974 {
6975         struct bpf_security_struct *bpfsec;
6976
6977         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6978         if (!bpfsec)
6979                 return -ENOMEM;
6980
6981         bpfsec->sid = current_sid();
6982         token->security = bpfsec;
6983
6984         return 0;
6985 }
6986
6987 static void selinux_bpf_token_free(struct bpf_token *token)
6988 {
6989         struct bpf_security_struct *bpfsec = token->security;
6990
6991         token->security = NULL;
6992         kfree(bpfsec);
6993 }
6994 #endif
6995
6996 struct lsm_blob_sizes selinux_blob_sizes __ro_after_init = {
6997         .lbs_cred = sizeof(struct task_security_struct),
6998         .lbs_file = sizeof(struct file_security_struct),
6999         .lbs_inode = sizeof(struct inode_security_struct),
7000         .lbs_ipc = sizeof(struct ipc_security_struct),
7001         .lbs_msg_msg = sizeof(struct msg_security_struct),
7002         .lbs_superblock = sizeof(struct superblock_security_struct),
7003         .lbs_xattr_count = SELINUX_INODE_INIT_XATTRS,
7004 };
7005
7006 #ifdef CONFIG_PERF_EVENTS
7007 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
7008 {
7009         u32 requested, sid = current_sid();
7010
7011         if (type == PERF_SECURITY_OPEN)
7012                 requested = PERF_EVENT__OPEN;
7013         else if (type == PERF_SECURITY_CPU)
7014                 requested = PERF_EVENT__CPU;
7015         else if (type == PERF_SECURITY_KERNEL)
7016                 requested = PERF_EVENT__KERNEL;
7017         else if (type == PERF_SECURITY_TRACEPOINT)
7018                 requested = PERF_EVENT__TRACEPOINT;
7019         else
7020                 return -EINVAL;
7021
7022         return avc_has_perm(sid, sid, SECCLASS_PERF_EVENT,
7023                             requested, NULL);
7024 }
7025
7026 static int selinux_perf_event_alloc(struct perf_event *event)
7027 {
7028         struct perf_event_security_struct *perfsec;
7029
7030         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
7031         if (!perfsec)
7032                 return -ENOMEM;
7033
7034         perfsec->sid = current_sid();
7035         event->security = perfsec;
7036
7037         return 0;
7038 }
7039
7040 static void selinux_perf_event_free(struct perf_event *event)
7041 {
7042         struct perf_event_security_struct *perfsec = event->security;
7043
7044         event->security = NULL;
7045         kfree(perfsec);
7046 }
7047
7048 static int selinux_perf_event_read(struct perf_event *event)
7049 {
7050         struct perf_event_security_struct *perfsec = event->security;
7051         u32 sid = current_sid();
7052
7053         return avc_has_perm(sid, perfsec->sid,
7054                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
7055 }
7056
7057 static int selinux_perf_event_write(struct perf_event *event)
7058 {
7059         struct perf_event_security_struct *perfsec = event->security;
7060         u32 sid = current_sid();
7061
7062         return avc_has_perm(sid, perfsec->sid,
7063                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
7064 }
7065 #endif
7066
7067 #ifdef CONFIG_IO_URING
7068 /**
7069  * selinux_uring_override_creds - check the requested cred override
7070  * @new: the target creds
7071  *
7072  * Check to see if the current task is allowed to override it's credentials
7073  * to service an io_uring operation.
7074  */
7075 static int selinux_uring_override_creds(const struct cred *new)
7076 {
7077         return avc_has_perm(current_sid(), cred_sid(new),
7078                             SECCLASS_IO_URING, IO_URING__OVERRIDE_CREDS, NULL);
7079 }
7080
7081 /**
7082  * selinux_uring_sqpoll - check if a io_uring polling thread can be created
7083  *
7084  * Check to see if the current task is allowed to create a new io_uring
7085  * kernel polling thread.
7086  */
7087 static int selinux_uring_sqpoll(void)
7088 {
7089         u32 sid = current_sid();
7090
7091         return avc_has_perm(sid, sid,
7092                             SECCLASS_IO_URING, IO_URING__SQPOLL, NULL);
7093 }
7094
7095 /**
7096  * selinux_uring_cmd - check if IORING_OP_URING_CMD is allowed
7097  * @ioucmd: the io_uring command structure
7098  *
7099  * Check to see if the current domain is allowed to execute an
7100  * IORING_OP_URING_CMD against the device/file specified in @ioucmd.
7101  *
7102  */
7103 static int selinux_uring_cmd(struct io_uring_cmd *ioucmd)
7104 {
7105         struct file *file = ioucmd->file;
7106         struct inode *inode = file_inode(file);
7107         struct inode_security_struct *isec = selinux_inode(inode);
7108         struct common_audit_data ad;
7109
7110         ad.type = LSM_AUDIT_DATA_FILE;
7111         ad.u.file = file;
7112
7113         return avc_has_perm(current_sid(), isec->sid,
7114                             SECCLASS_IO_URING, IO_URING__CMD, &ad);
7115 }
7116 #endif /* CONFIG_IO_URING */
7117
7118 static const struct lsm_id selinux_lsmid = {
7119         .name = "selinux",
7120         .id = LSM_ID_SELINUX,
7121 };
7122
7123 /*
7124  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
7125  * 1. any hooks that don't belong to (2.) or (3.) below,
7126  * 2. hooks that both access structures allocated by other hooks, and allocate
7127  *    structures that can be later accessed by other hooks (mostly "cloning"
7128  *    hooks),
7129  * 3. hooks that only allocate structures that can be later accessed by other
7130  *    hooks ("allocating" hooks).
7131  *
7132  * Please follow block comment delimiters in the list to keep this order.
7133  */
7134 static struct security_hook_list selinux_hooks[] __ro_after_init = {
7135         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
7136         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
7137         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
7138         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
7139
7140         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
7141         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
7142         LSM_HOOK_INIT(capget, selinux_capget),
7143         LSM_HOOK_INIT(capset, selinux_capset),
7144         LSM_HOOK_INIT(capable, selinux_capable),
7145         LSM_HOOK_INIT(quotactl, selinux_quotactl),
7146         LSM_HOOK_INIT(quota_on, selinux_quota_on),
7147         LSM_HOOK_INIT(syslog, selinux_syslog),
7148         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
7149
7150         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
7151
7152         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
7153         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
7154         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
7155
7156         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
7157         LSM_HOOK_INIT(sb_mnt_opts_compat, selinux_sb_mnt_opts_compat),
7158         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
7159         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
7160         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
7161         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
7162         LSM_HOOK_INIT(sb_mount, selinux_mount),
7163         LSM_HOOK_INIT(sb_umount, selinux_umount),
7164         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
7165         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
7166
7167         LSM_HOOK_INIT(move_mount, selinux_move_mount),
7168
7169         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
7170         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
7171
7172         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
7173         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
7174         LSM_HOOK_INIT(inode_init_security_anon, selinux_inode_init_security_anon),
7175         LSM_HOOK_INIT(inode_create, selinux_inode_create),
7176         LSM_HOOK_INIT(inode_link, selinux_inode_link),
7177         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
7178         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
7179         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
7180         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
7181         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
7182         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
7183         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7184         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7185         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7186         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7187         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7188         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7189         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7190         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7191         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7192         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7193         LSM_HOOK_INIT(inode_set_acl, selinux_inode_set_acl),
7194         LSM_HOOK_INIT(inode_get_acl, selinux_inode_get_acl),
7195         LSM_HOOK_INIT(inode_remove_acl, selinux_inode_remove_acl),
7196         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7197         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7198         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7199         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7200         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7201         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7202         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7203
7204         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7205
7206         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7207         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7208         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7209         LSM_HOOK_INIT(file_ioctl_compat, selinux_file_ioctl_compat),
7210         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7211         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7212         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7213         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7214         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7215         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7216         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7217         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7218
7219         LSM_HOOK_INIT(file_open, selinux_file_open),
7220
7221         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7222         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7223         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7224         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7225         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7226         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7227         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7228         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7229         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7230         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7231         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7232         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7233         LSM_HOOK_INIT(current_getsecid_subj, selinux_current_getsecid_subj),
7234         LSM_HOOK_INIT(task_getsecid_obj, selinux_task_getsecid_obj),
7235         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7236         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7237         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7238         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7239         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7240         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7241         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7242         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7243         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7244         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7245         LSM_HOOK_INIT(userns_create, selinux_userns_create),
7246
7247         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7248         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7249
7250         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7251         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7252         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7253         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7254
7255         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7256         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7257         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7258
7259         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7260         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7261         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7262
7263         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7264
7265         LSM_HOOK_INIT(getselfattr, selinux_getselfattr),
7266         LSM_HOOK_INIT(setselfattr, selinux_setselfattr),
7267         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7268         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7269
7270         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7271         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7272         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7273         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7274         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7275         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7276
7277         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7278         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7279
7280         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7281         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7282         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7283         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7284         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7285         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7286         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7287         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7288         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7289         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7290         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7291         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7292         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7293         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7294         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7295         LSM_HOOK_INIT(socket_getpeersec_stream,
7296                         selinux_socket_getpeersec_stream),
7297         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7298         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7299         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7300         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7301         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7302         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7303         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7304         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7305         LSM_HOOK_INIT(sctp_assoc_established, selinux_sctp_assoc_established),
7306         LSM_HOOK_INIT(mptcp_add_subflow, selinux_mptcp_add_subflow),
7307         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7308         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7309         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7310         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7311         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7312         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7313         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7314         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7315         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7316         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7317         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7318         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7319 #ifdef CONFIG_SECURITY_INFINIBAND
7320         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7321         LSM_HOOK_INIT(ib_endport_manage_subnet,
7322                       selinux_ib_endport_manage_subnet),
7323         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7324 #endif
7325 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7326         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7327         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7328         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7329         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7330         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7331         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7332                         selinux_xfrm_state_pol_flow_match),
7333         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7334 #endif
7335
7336 #ifdef CONFIG_KEYS
7337         LSM_HOOK_INIT(key_free, selinux_key_free),
7338         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7339         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7340 #ifdef CONFIG_KEY_NOTIFICATIONS
7341         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7342 #endif
7343 #endif
7344
7345 #ifdef CONFIG_AUDIT
7346         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7347         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7348         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7349 #endif
7350
7351 #ifdef CONFIG_BPF_SYSCALL
7352         LSM_HOOK_INIT(bpf, selinux_bpf),
7353         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7354         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7355         LSM_HOOK_INIT(bpf_map_free, selinux_bpf_map_free),
7356         LSM_HOOK_INIT(bpf_prog_free, selinux_bpf_prog_free),
7357         LSM_HOOK_INIT(bpf_token_free, selinux_bpf_token_free),
7358 #endif
7359
7360 #ifdef CONFIG_PERF_EVENTS
7361         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7362         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7363         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7364         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7365 #endif
7366
7367 #ifdef CONFIG_IO_URING
7368         LSM_HOOK_INIT(uring_override_creds, selinux_uring_override_creds),
7369         LSM_HOOK_INIT(uring_sqpoll, selinux_uring_sqpoll),
7370         LSM_HOOK_INIT(uring_cmd, selinux_uring_cmd),
7371 #endif
7372
7373         /*
7374          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7375          */
7376         LSM_HOOK_INIT(fs_context_submount, selinux_fs_context_submount),
7377         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7378         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7379         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7380 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7381         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7382 #endif
7383
7384         /*
7385          * PUT "ALLOCATING" HOOKS HERE
7386          */
7387         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7388         LSM_HOOK_INIT(msg_queue_alloc_security,
7389                       selinux_msg_queue_alloc_security),
7390         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7391         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7392         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7393         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7394         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7395         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7396         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7397         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7398 #ifdef CONFIG_SECURITY_INFINIBAND
7399         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7400 #endif
7401 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7402         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7403         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7404         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7405                       selinux_xfrm_state_alloc_acquire),
7406 #endif
7407 #ifdef CONFIG_KEYS
7408         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7409 #endif
7410 #ifdef CONFIG_AUDIT
7411         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7412 #endif
7413 #ifdef CONFIG_BPF_SYSCALL
7414         LSM_HOOK_INIT(bpf_map_create, selinux_bpf_map_create),
7415         LSM_HOOK_INIT(bpf_prog_load, selinux_bpf_prog_load),
7416         LSM_HOOK_INIT(bpf_token_create, selinux_bpf_token_create),
7417 #endif
7418 #ifdef CONFIG_PERF_EVENTS
7419         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7420 #endif
7421 };
7422
7423 static __init int selinux_init(void)
7424 {
7425         pr_info("SELinux:  Initializing.\n");
7426
7427         memset(&selinux_state, 0, sizeof(selinux_state));
7428         enforcing_set(selinux_enforcing_boot);
7429         selinux_avc_init();
7430         mutex_init(&selinux_state.status_lock);
7431         mutex_init(&selinux_state.policy_mutex);
7432
7433         /* Set the security state for the initial task. */
7434         cred_init_security();
7435
7436         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7437         if (!default_noexec)
7438                 pr_notice("SELinux:  virtual memory is executable by default\n");
7439
7440         avc_init();
7441
7442         avtab_cache_init();
7443
7444         ebitmap_cache_init();
7445
7446         hashtab_cache_init();
7447
7448         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks),
7449                            &selinux_lsmid);
7450
7451         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7452                 panic("SELinux: Unable to register AVC netcache callback\n");
7453
7454         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7455                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7456
7457         if (selinux_enforcing_boot)
7458                 pr_debug("SELinux:  Starting in enforcing mode\n");
7459         else
7460                 pr_debug("SELinux:  Starting in permissive mode\n");
7461
7462         fs_validate_description("selinux", selinux_fs_parameters);
7463
7464         return 0;
7465 }
7466
7467 static void delayed_superblock_init(struct super_block *sb, void *unused)
7468 {
7469         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7470 }
7471
7472 void selinux_complete_init(void)
7473 {
7474         pr_debug("SELinux:  Completing initialization.\n");
7475
7476         /* Set up any superblocks initialized prior to the policy load. */
7477         pr_debug("SELinux:  Setting up existing superblocks.\n");
7478         iterate_supers(delayed_superblock_init, NULL);
7479 }
7480
7481 /* SELinux requires early initialization in order to label
7482    all processes and objects when they are created. */
7483 DEFINE_LSM(selinux) = {
7484         .name = "selinux",
7485         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7486         .enabled = &selinux_enabled_boot,
7487         .blobs = &selinux_blob_sizes,
7488         .init = selinux_init,
7489 };
7490
7491 #if defined(CONFIG_NETFILTER)
7492 static const struct nf_hook_ops selinux_nf_ops[] = {
7493         {
7494                 .hook =         selinux_ip_postroute,
7495                 .pf =           NFPROTO_IPV4,
7496                 .hooknum =      NF_INET_POST_ROUTING,
7497                 .priority =     NF_IP_PRI_SELINUX_LAST,
7498         },
7499         {
7500                 .hook =         selinux_ip_forward,
7501                 .pf =           NFPROTO_IPV4,
7502                 .hooknum =      NF_INET_FORWARD,
7503                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7504         },
7505         {
7506                 .hook =         selinux_ip_output,
7507                 .pf =           NFPROTO_IPV4,
7508                 .hooknum =      NF_INET_LOCAL_OUT,
7509                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7510         },
7511 #if IS_ENABLED(CONFIG_IPV6)
7512         {
7513                 .hook =         selinux_ip_postroute,
7514                 .pf =           NFPROTO_IPV6,
7515                 .hooknum =      NF_INET_POST_ROUTING,
7516                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7517         },
7518         {
7519                 .hook =         selinux_ip_forward,
7520                 .pf =           NFPROTO_IPV6,
7521                 .hooknum =      NF_INET_FORWARD,
7522                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7523         },
7524         {
7525                 .hook =         selinux_ip_output,
7526                 .pf =           NFPROTO_IPV6,
7527                 .hooknum =      NF_INET_LOCAL_OUT,
7528                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7529         },
7530 #endif  /* IPV6 */
7531 };
7532
7533 static int __net_init selinux_nf_register(struct net *net)
7534 {
7535         return nf_register_net_hooks(net, selinux_nf_ops,
7536                                      ARRAY_SIZE(selinux_nf_ops));
7537 }
7538
7539 static void __net_exit selinux_nf_unregister(struct net *net)
7540 {
7541         nf_unregister_net_hooks(net, selinux_nf_ops,
7542                                 ARRAY_SIZE(selinux_nf_ops));
7543 }
7544
7545 static struct pernet_operations selinux_net_ops = {
7546         .init = selinux_nf_register,
7547         .exit = selinux_nf_unregister,
7548 };
7549
7550 static int __init selinux_nf_ip_init(void)
7551 {
7552         int err;
7553
7554         if (!selinux_enabled_boot)
7555                 return 0;
7556
7557         pr_debug("SELinux:  Registering netfilter hooks\n");
7558
7559         err = register_pernet_subsys(&selinux_net_ops);
7560         if (err)
7561                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7562
7563         return 0;
7564 }
7565 __initcall(selinux_nf_ip_init);
7566 #endif /* CONFIG_NETFILTER */