fs/nfs/fs_context.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/fs/nfs/fs_context.c
   4  *
   5  * Copyright (C) 1992 Rick Sladkey
   6  * Conversion to new mount api Copyright (C) David Howells
   7  *
   8  * NFS mount handling.
   9  *
  10  * Split from fs/nfs/super.c by David Howells <dhowells@redhat.com>
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/fs.h>
  15 #include <linux/fs_context.h>
  16 #include <linux/fs_parser.h>
  17 #include <linux/nfs_fs.h>
  18 #include <linux/nfs_mount.h>
  19 #include <linux/nfs4_mount.h>
  20 #include "nfs.h"
  21 #include "internal.h"
  22
  23 #define NFSDBG_FACILITY         NFSDBG_MOUNT
  24
  25 #if IS_ENABLED(CONFIG_NFS_V3)
  26 #define NFS_DEFAULT_VERSION 3
  27 #else
  28 #define NFS_DEFAULT_VERSION 2
  29 #endif
  30
  31 #define NFS_MAX_CONNECTIONS 16
  32
  33 enum nfs_param {
  34         Opt_ac,
  35         Opt_acdirmax,
  36         Opt_acdirmin,
  37         Opt_acl,
  38         Opt_acregmax,
  39         Opt_acregmin,
  40         Opt_actimeo,
  41         Opt_addr,
  42         Opt_bg,
  43         Opt_bsize,
  44         Opt_clientaddr,
  45         Opt_cto,
  46         Opt_fg,
  47         Opt_fscache,
  48         Opt_fscache_flag,
  49         Opt_hard,
  50         Opt_intr,
  51         Opt_local_lock,
  52         Opt_lock,
  53         Opt_lookupcache,
  54         Opt_migration,
  55         Opt_minorversion,
  56         Opt_mountaddr,
  57         Opt_mounthost,
  58         Opt_mountport,
  59         Opt_mountproto,
  60         Opt_mountvers,
  61         Opt_namelen,
  62         Opt_nconnect,
  63         Opt_max_connect,
  64         Opt_port,
  65         Opt_posix,
  66         Opt_proto,
  67         Opt_rdirplus,
  68         Opt_rdma,
  69         Opt_resvport,
  70         Opt_retrans,
  71         Opt_retry,
  72         Opt_rsize,
  73         Opt_sec,
  74         Opt_sharecache,
  75         Opt_sloppy,
  76         Opt_soft,
  77         Opt_softerr,
  78         Opt_softreval,
  79         Opt_source,
  80         Opt_tcp,
  81         Opt_timeo,
  82         Opt_udp,
  83         Opt_v,
  84         Opt_vers,
  85         Opt_wsize,
  86         Opt_write,
  87 };
  88
  89 enum {
  90         Opt_local_lock_all,
  91         Opt_local_lock_flock,
  92         Opt_local_lock_none,
  93         Opt_local_lock_posix,
  94 };
  95
  96 static const struct constant_table nfs_param_enums_local_lock[] = {
  97         { "all",                Opt_local_lock_all },
  98         { "flock",      Opt_local_lock_flock },
  99         { "posix",      Opt_local_lock_posix },
 100         { "none",               Opt_local_lock_none },
 101         {}
 102 };
 103
 104 enum {
 105         Opt_lookupcache_all,
 106         Opt_lookupcache_none,
 107         Opt_lookupcache_positive,
 108 };
 109
 110 static const struct constant_table nfs_param_enums_lookupcache[] = {
 111         { "all",                Opt_lookupcache_all },
 112         { "none",               Opt_lookupcache_none },
 113         { "pos",                Opt_lookupcache_positive },
 114         { "positive",           Opt_lookupcache_positive },
 115         {}
 116 };
 117
 118 enum {
 119         Opt_write_lazy,
 120         Opt_write_eager,
 121         Opt_write_wait,
 122 };
 123
 124 static const struct constant_table nfs_param_enums_write[] = {
 125         { "lazy",               Opt_write_lazy },
 126         { "eager",              Opt_write_eager },
 127         { "wait",               Opt_write_wait },
 128         {}
 129 };
 130
 131 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 132         fsparam_flag_no("ac",           Opt_ac),
 133         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 134         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 135         fsparam_flag_no("acl",          Opt_acl),
 136         fsparam_u32   ("acregmax",      Opt_acregmax),
 137         fsparam_u32   ("acregmin",      Opt_acregmin),
 138         fsparam_u32   ("actimeo",       Opt_actimeo),
 139         fsparam_string("addr",          Opt_addr),
 140         fsparam_flag  ("bg",            Opt_bg),
 141         fsparam_u32   ("bsize",         Opt_bsize),
 142         fsparam_string("clientaddr",    Opt_clientaddr),
 143         fsparam_flag_no("cto",          Opt_cto),
 144         fsparam_flag  ("fg",            Opt_fg),
 145         fsparam_flag_no("fsc",          Opt_fscache_flag),
 146         fsparam_string("fsc",           Opt_fscache),
 147         fsparam_flag  ("hard",          Opt_hard),
 148         __fsparam(NULL, "intr",         Opt_intr,
 149                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 150         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 151         fsparam_flag_no("lock",         Opt_lock),
 152         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 153         fsparam_flag_no("migration",    Opt_migration),
 154         fsparam_u32   ("minorversion",  Opt_minorversion),
 155         fsparam_string("mountaddr",     Opt_mountaddr),
 156         fsparam_string("mounthost",     Opt_mounthost),
 157         fsparam_u32   ("mountport",     Opt_mountport),
 158         fsparam_string("mountproto",    Opt_mountproto),
 159         fsparam_u32   ("mountvers",     Opt_mountvers),
 160         fsparam_u32   ("namlen",        Opt_namelen),
 161         fsparam_u32   ("nconnect",      Opt_nconnect),
 162         fsparam_u32   ("max_connect",   Opt_max_connect),
 163         fsparam_string("nfsvers",       Opt_vers),
 164         fsparam_u32   ("port",          Opt_port),
 165         fsparam_flag_no("posix",        Opt_posix),
 166         fsparam_string("proto",         Opt_proto),
 167         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 168         fsparam_flag  ("rdma",          Opt_rdma),
 169         fsparam_flag_no("resvport",     Opt_resvport),
 170         fsparam_u32   ("retrans",       Opt_retrans),
 171         fsparam_string("retry",         Opt_retry),
 172         fsparam_u32   ("rsize",         Opt_rsize),
 173         fsparam_string("sec",           Opt_sec),
 174         fsparam_flag_no("sharecache",   Opt_sharecache),
 175         fsparam_flag  ("sloppy",        Opt_sloppy),
 176         fsparam_flag  ("soft",          Opt_soft),
 177         fsparam_flag  ("softerr",       Opt_softerr),
 178         fsparam_flag  ("softreval",     Opt_softreval),
 179         fsparam_string("source",        Opt_source),
 180         fsparam_flag  ("tcp",           Opt_tcp),
 181         fsparam_u32   ("timeo",         Opt_timeo),
 182         fsparam_flag  ("udp",           Opt_udp),
 183         fsparam_flag  ("v2",            Opt_v),
 184         fsparam_flag  ("v3",            Opt_v),
 185         fsparam_flag  ("v4",            Opt_v),
 186         fsparam_flag  ("v4.0",          Opt_v),
 187         fsparam_flag  ("v4.1",          Opt_v),
 188         fsparam_flag  ("v4.2",          Opt_v),
 189         fsparam_string("vers",          Opt_vers),
 190         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 191         fsparam_u32   ("wsize",         Opt_wsize),
 192         {}
 193 };
 194
 195 enum {
 196         Opt_vers_2,
 197         Opt_vers_3,
 198         Opt_vers_4,
 199         Opt_vers_4_0,
 200         Opt_vers_4_1,
 201         Opt_vers_4_2,
 202 };
 203
 204 static const struct constant_table nfs_vers_tokens[] = {
 205         { "2",          Opt_vers_2 },
 206         { "3",          Opt_vers_3 },
 207         { "4",          Opt_vers_4 },
 208         { "4.0",        Opt_vers_4_0 },
 209         { "4.1",        Opt_vers_4_1 },
 210         { "4.2",        Opt_vers_4_2 },
 211         {}
 212 };
 213
 214 enum {
 215         Opt_xprt_rdma,
 216         Opt_xprt_rdma6,
 217         Opt_xprt_tcp,
 218         Opt_xprt_tcp6,
 219         Opt_xprt_udp,
 220         Opt_xprt_udp6,
 221         nr__Opt_xprt
 222 };
 223
 224 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 225         { "rdma",       Opt_xprt_rdma },
 226         { "rdma6",      Opt_xprt_rdma6 },
 227         { "tcp",        Opt_xprt_tcp },
 228         { "tcp6",       Opt_xprt_tcp6 },
 229         { "udp",        Opt_xprt_udp },
 230         { "udp6",       Opt_xprt_udp6 },
 231         {}
 232 };
 233
 234 enum {
 235         Opt_sec_krb5,
 236         Opt_sec_krb5i,
 237         Opt_sec_krb5p,
 238         Opt_sec_lkey,
 239         Opt_sec_lkeyi,
 240         Opt_sec_lkeyp,
 241         Opt_sec_none,
 242         Opt_sec_spkm,
 243         Opt_sec_spkmi,
 244         Opt_sec_spkmp,
 245         Opt_sec_sys,
 246         nr__Opt_sec
 247 };
 248
 249 static const struct constant_table nfs_secflavor_tokens[] = {
 250         { "krb5",       Opt_sec_krb5 },
 251         { "krb5i",      Opt_sec_krb5i },
 252         { "krb5p",      Opt_sec_krb5p },
 253         { "lkey",       Opt_sec_lkey },
 254         { "lkeyi",      Opt_sec_lkeyi },
 255         { "lkeyp",      Opt_sec_lkeyp },
 256         { "none",       Opt_sec_none },
 257         { "null",       Opt_sec_none },
 258         { "spkm3",      Opt_sec_spkm },
 259         { "spkm3i",     Opt_sec_spkmi },
 260         { "spkm3p",     Opt_sec_spkmp },
 261         { "sys",        Opt_sec_sys },
 262         {}
 263 };
 264
 265 /*
 266  * Sanity-check a server address provided by the mount command.
 267  *
 268  * Address family must be initialized, and address must not be
 269  * the ANY address for that family.
 270  */
 271 static int nfs_verify_server_address(struct sockaddr *addr)
 272 {
 273         switch (addr->sa_family) {
 274         case AF_INET: {
 275                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 276                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 277         }
 278         case AF_INET6: {
 279                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 280                 return !ipv6_addr_any(sa);
 281         }
 282         }
 283
 284         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 285         return 0;
 286 }
 287
 288 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
 289 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 290 {
 291         return true;
 292 }
 293 #else
 294 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 295 {
 296         if (ctx->version == 4)
 297                 return true;
 298         return false;
 299 }
 300 #endif
 301
 302 /*
 303  * Sanity check the NFS transport protocol.
 304  */
 305 static int nfs_validate_transport_protocol(struct fs_context *fc,
 306                                            struct nfs_fs_context *ctx)
 307 {
 308         switch (ctx->nfs_server.protocol) {
 309         case XPRT_TRANSPORT_UDP:
 310                 if (nfs_server_transport_udp_invalid(ctx))
 311                         goto out_invalid_transport_udp;
 312                 break;
 313         case XPRT_TRANSPORT_TCP:
 314         case XPRT_TRANSPORT_RDMA:
 315                 break;
 316         default:
 317                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 318         }
 319         return 0;
 320 out_invalid_transport_udp:
 321         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
 322 }
 323
 324 /*
 325  * For text based NFSv2/v3 mounts, the mount protocol transport default
 326  * settings should depend upon the specified NFS transport.
 327  */
 328 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 329 {
 330         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 331             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 332                         return;
 333         switch (ctx->nfs_server.protocol) {
 334         case XPRT_TRANSPORT_UDP:
 335                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 336                 break;
 337         case XPRT_TRANSPORT_TCP:
 338         case XPRT_TRANSPORT_RDMA:
 339                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 340         }
 341 }
 342
 343 /*
 344  * Add 'flavor' to 'auth_info' if not already present.
 345  * Returns true if 'flavor' ends up in the list, false otherwise
 346  */
 347 static int nfs_auth_info_add(struct fs_context *fc,
 348                              struct nfs_auth_info *auth_info,
 349                              rpc_authflavor_t flavor)
 350 {
 351         unsigned int i;
 352         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 353
 354         /* make sure this flavor isn't already in the list */
 355         for (i = 0; i < auth_info->flavor_len; i++) {
 356                 if (flavor == auth_info->flavors[i])
 357                         return 0;
 358         }
 359
 360         if (auth_info->flavor_len + 1 >= max_flavor_len)
 361                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 362
 363         auth_info->flavors[auth_info->flavor_len++] = flavor;
 364         return 0;
 365 }
 366
 367 /*
 368  * Parse the value of the 'sec=' option.
 369  */
 370 static int nfs_parse_security_flavors(struct fs_context *fc,
 371                                       struct fs_parameter *param)
 372 {
 373         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 374         rpc_authflavor_t pseudoflavor;
 375         char *string = param->string, *p;
 376         int ret;
 377
 378         dfprintk(MOUNT, "NFS: parsing %s=%s option\n", param->key, param->string);
 379
 380         while ((p = strsep(&string, ":")) != NULL) {
 381                 if (!*p)
 382                         continue;
 383                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 384                 case Opt_sec_none:
 385                         pseudoflavor = RPC_AUTH_NULL;
 386                         break;
 387                 case Opt_sec_sys:
 388                         pseudoflavor = RPC_AUTH_UNIX;
 389                         break;
 390                 case Opt_sec_krb5:
 391                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 392                         break;
 393                 case Opt_sec_krb5i:
 394                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 395                         break;
 396                 case Opt_sec_krb5p:
 397                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 398                         break;
 399                 case Opt_sec_lkey:
 400                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 401                         break;
 402                 case Opt_sec_lkeyi:
 403                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 404                         break;
 405                 case Opt_sec_lkeyp:
 406                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 407                         break;
 408                 case Opt_sec_spkm:
 409                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 410                         break;
 411                 case Opt_sec_spkmi:
 412                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 413                         break;
 414                 case Opt_sec_spkmp:
 415                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 416                         break;
 417                 default:
 418                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 419                 }
 420
 421                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 422                 if (ret < 0)
 423                         return ret;
 424         }
 425
 426         return 0;
 427 }
 428
 429 static int nfs_parse_version_string(struct fs_context *fc,
 430                                     const char *string)
 431 {
 432         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 433
 434         ctx->flags &= ~NFS_MOUNT_VER3;
 435         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 436         case Opt_vers_2:
 437                 ctx->version = 2;
 438                 break;
 439         case Opt_vers_3:
 440                 ctx->flags |= NFS_MOUNT_VER3;
 441                 ctx->version = 3;
 442                 break;
 443         case Opt_vers_4:
 444                 /* Backward compatibility option. In future,
 445                  * the mount program should always supply
 446                  * a NFSv4 minor version number.
 447                  */
 448                 ctx->version = 4;
 449                 break;
 450         case Opt_vers_4_0:
 451                 ctx->version = 4;
 452                 ctx->minorversion = 0;
 453                 break;
 454         case Opt_vers_4_1:
 455                 ctx->version = 4;
 456                 ctx->minorversion = 1;
 457                 break;
 458         case Opt_vers_4_2:
 459                 ctx->version = 4;
 460                 ctx->minorversion = 2;
 461                 break;
 462         default:
 463                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 464         }
 465         return 0;
 466 }
 467
 468 /*
 469  * Parse a single mount parameter.
 470  */
 471 static int nfs_fs_context_parse_param(struct fs_context *fc,
 472                                       struct fs_parameter *param)
 473 {
 474         struct fs_parse_result result;
 475         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 476         unsigned short protofamily, mountfamily;
 477         unsigned int len;
 478         int ret, opt;
 479
 480         dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", param->key);
 481
 482         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 483         if (opt < 0)
 484                 return ctx->sloppy ? 1 : opt;
 485
 486         if (fc->security)
 487                 ctx->has_sec_mnt_opts = 1;
 488
 489         switch (opt) {
 490         case Opt_source:
 491                 if (fc->source)
 492                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 493                 fc->source = param->string;
 494                 param->string = NULL;
 495                 break;
 496
 497                 /*
 498                  * boolean options:  foo/nofoo
 499                  */
 500         case Opt_soft:
 501                 ctx->flags |= NFS_MOUNT_SOFT;
 502                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 503                 break;
 504         case Opt_softerr:
 505                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 506                 ctx->flags &= ~NFS_MOUNT_SOFT;
 507                 break;
 508         case Opt_hard:
 509                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 510                                 NFS_MOUNT_SOFTERR |
 511                                 NFS_MOUNT_SOFTREVAL);
 512                 break;
 513         case Opt_softreval:
 514                 if (result.negated)
 515                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 516                 else
 517                         ctx->flags |= NFS_MOUNT_SOFTREVAL;
 518                 break;
 519         case Opt_posix:
 520                 if (result.negated)
 521                         ctx->flags &= ~NFS_MOUNT_POSIX;
 522                 else
 523                         ctx->flags |= NFS_MOUNT_POSIX;
 524                 break;
 525         case Opt_cto:
 526                 if (result.negated)
 527                         ctx->flags |= NFS_MOUNT_NOCTO;
 528                 else
 529                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 530                 break;
 531         case Opt_ac:
 532                 if (result.negated)
 533                         ctx->flags |= NFS_MOUNT_NOAC;
 534                 else
 535                         ctx->flags &= ~NFS_MOUNT_NOAC;
 536                 break;
 537         case Opt_lock:
 538                 if (result.negated) {
 539                         ctx->flags |= NFS_MOUNT_NONLM;
 540                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 541                 } else {
 542                         ctx->flags &= ~NFS_MOUNT_NONLM;
 543                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 544                 }
 545                 break;
 546         case Opt_udp:
 547                 ctx->flags &= ~NFS_MOUNT_TCP;
 548                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 549                 break;
 550         case Opt_tcp:
 551         case Opt_rdma:
 552                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 553                 ret = xprt_find_transport_ident(param->key);
 554                 if (ret < 0)
 555                         goto out_bad_transport;
 556                 ctx->nfs_server.protocol = ret;
 557                 break;
 558         case Opt_acl:
 559                 if (result.negated)
 560                         ctx->flags |= NFS_MOUNT_NOACL;
 561                 else
 562                         ctx->flags &= ~NFS_MOUNT_NOACL;
 563                 break;
 564         case Opt_rdirplus:
 565                 if (result.negated)
 566                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 567                 else
 568                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 569                 break;
 570         case Opt_sharecache:
 571                 if (result.negated)
 572                         ctx->flags |= NFS_MOUNT_UNSHARED;
 573                 else
 574                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 575                 break;
 576         case Opt_resvport:
 577                 if (result.negated)
 578                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 579                 else
 580                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 581                 break;
 582         case Opt_fscache_flag:
 583                 if (result.negated)
 584                         ctx->options &= ~NFS_OPTION_FSCACHE;
 585                 else
 586                         ctx->options |= NFS_OPTION_FSCACHE;
 587                 kfree(ctx->fscache_uniq);
 588                 ctx->fscache_uniq = NULL;
 589                 break;
 590         case Opt_fscache:
 591                 ctx->options |= NFS_OPTION_FSCACHE;
 592                 kfree(ctx->fscache_uniq);
 593                 ctx->fscache_uniq = param->string;
 594                 param->string = NULL;
 595                 break;
 596         case Opt_migration:
 597                 if (result.negated)
 598                         ctx->options &= ~NFS_OPTION_MIGRATION;
 599                 else
 600                         ctx->options |= NFS_OPTION_MIGRATION;
 601                 break;
 602
 603                 /*
 604                  * options that take numeric values
 605                  */
 606         case Opt_port:
 607                 if (result.uint_32 > USHRT_MAX)
 608                         goto out_of_bounds;
 609                 ctx->nfs_server.port = result.uint_32;
 610                 break;
 611         case Opt_rsize:
 612                 ctx->rsize = result.uint_32;
 613                 break;
 614         case Opt_wsize:
 615                 ctx->wsize = result.uint_32;
 616                 break;
 617         case Opt_bsize:
 618                 ctx->bsize = result.uint_32;
 619                 break;
 620         case Opt_timeo:
 621                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 622                         goto out_of_bounds;
 623                 ctx->timeo = result.uint_32;
 624                 break;
 625         case Opt_retrans:
 626                 if (result.uint_32 > INT_MAX)
 627                         goto out_of_bounds;
 628                 ctx->retrans = result.uint_32;
 629                 break;
 630         case Opt_acregmin:
 631                 ctx->acregmin = result.uint_32;
 632                 break;
 633         case Opt_acregmax:
 634                 ctx->acregmax = result.uint_32;
 635                 break;
 636         case Opt_acdirmin:
 637                 ctx->acdirmin = result.uint_32;
 638                 break;
 639         case Opt_acdirmax:
 640                 ctx->acdirmax = result.uint_32;
 641                 break;
 642         case Opt_actimeo:
 643                 ctx->acregmin = result.uint_32;
 644                 ctx->acregmax = result.uint_32;
 645                 ctx->acdirmin = result.uint_32;
 646                 ctx->acdirmax = result.uint_32;
 647                 break;
 648         case Opt_namelen:
 649                 ctx->namlen = result.uint_32;
 650                 break;
 651         case Opt_mountport:
 652                 if (result.uint_32 > USHRT_MAX)
 653                         goto out_of_bounds;
 654                 ctx->mount_server.port = result.uint_32;
 655                 break;
 656         case Opt_mountvers:
 657                 if (result.uint_32 < NFS_MNT_VERSION ||
 658                     result.uint_32 > NFS_MNT3_VERSION)
 659                         goto out_of_bounds;
 660                 ctx->mount_server.version = result.uint_32;
 661                 break;
 662         case Opt_minorversion:
 663                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 664                         goto out_of_bounds;
 665                 ctx->minorversion = result.uint_32;
 666                 break;
 667
 668                 /*
 669                  * options that take text values
 670                  */
 671         case Opt_v:
 672                 ret = nfs_parse_version_string(fc, param->key + 1);
 673                 if (ret < 0)
 674                         return ret;
 675                 break;
 676         case Opt_vers:
 677                 ret = nfs_parse_version_string(fc, param->string);
 678                 if (ret < 0)
 679                         return ret;
 680                 break;
 681         case Opt_sec:
 682                 ret = nfs_parse_security_flavors(fc, param);
 683                 if (ret < 0)
 684                         return ret;
 685                 break;
 686
 687         case Opt_proto:
 688                 protofamily = AF_INET;
 689                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 690                 case Opt_xprt_udp6:
 691                         protofamily = AF_INET6;
 692                         fallthrough;
 693                 case Opt_xprt_udp:
 694                         ctx->flags &= ~NFS_MOUNT_TCP;
 695                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 696                         break;
 697                 case Opt_xprt_tcp6:
 698                         protofamily = AF_INET6;
 699                         fallthrough;
 700                 case Opt_xprt_tcp:
 701                         ctx->flags |= NFS_MOUNT_TCP;
 702                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 703                         break;
 704                 case Opt_xprt_rdma6:
 705                         protofamily = AF_INET6;
 706                         fallthrough;
 707                 case Opt_xprt_rdma:
 708                         /* vector side protocols to TCP */
 709                         ctx->flags |= NFS_MOUNT_TCP;
 710                         ret = xprt_find_transport_ident(param->string);
 711                         if (ret < 0)
 712                                 goto out_bad_transport;
 713                         ctx->nfs_server.protocol = ret;
 714                         break;
 715                 default:
 716                         goto out_bad_transport;
 717                 }
 718
 719                 ctx->protofamily = protofamily;
 720                 break;
 721
 722         case Opt_mountproto:
 723                 mountfamily = AF_INET;
 724                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 725                 case Opt_xprt_udp6:
 726                         mountfamily = AF_INET6;
 727                         fallthrough;
 728                 case Opt_xprt_udp:
 729                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 730                         break;
 731                 case Opt_xprt_tcp6:
 732                         mountfamily = AF_INET6;
 733                         fallthrough;
 734                 case Opt_xprt_tcp:
 735                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 736                         break;
 737                 case Opt_xprt_rdma: /* not used for side protocols */
 738                 default:
 739                         goto out_bad_transport;
 740                 }
 741                 ctx->mountfamily = mountfamily;
 742                 break;
 743
 744         case Opt_addr:
 745                 len = rpc_pton(fc->net_ns, param->string, param->size,
 746                                &ctx->nfs_server.address,
 747                                sizeof(ctx->nfs_server._address));
 748                 if (len == 0)
 749                         goto out_invalid_address;
 750                 ctx->nfs_server.addrlen = len;
 751                 break;
 752         case Opt_clientaddr:
 753                 kfree(ctx->client_address);
 754                 ctx->client_address = param->string;
 755                 param->string = NULL;
 756                 break;
 757         case Opt_mounthost:
 758                 kfree(ctx->mount_server.hostname);
 759                 ctx->mount_server.hostname = param->string;
 760                 param->string = NULL;
 761                 break;
 762         case Opt_mountaddr:
 763                 len = rpc_pton(fc->net_ns, param->string, param->size,
 764                                &ctx->mount_server.address,
 765                                sizeof(ctx->mount_server._address));
 766                 if (len == 0)
 767                         goto out_invalid_address;
 768                 ctx->mount_server.addrlen = len;
 769                 break;
 770         case Opt_nconnect:
 771                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 772                         goto out_of_bounds;
 773                 ctx->nfs_server.nconnect = result.uint_32;
 774                 break;
 775         case Opt_max_connect:
 776                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
 777                         goto out_of_bounds;
 778                 ctx->nfs_server.max_connect = result.uint_32;
 779                 break;
 780         case Opt_lookupcache:
 781                 switch (result.uint_32) {
 782                 case Opt_lookupcache_all:
 783                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 784                         break;
 785                 case Opt_lookupcache_positive:
 786                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 787                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 788                         break;
 789                 case Opt_lookupcache_none:
 790                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 791                         break;
 792                 default:
 793                         goto out_invalid_value;
 794                 }
 795                 break;
 796         case Opt_local_lock:
 797                 switch (result.uint_32) {
 798                 case Opt_local_lock_all:
 799                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 800                                        NFS_MOUNT_LOCAL_FCNTL);
 801                         break;
 802                 case Opt_local_lock_flock:
 803                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 804                         break;
 805                 case Opt_local_lock_posix:
 806                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 807                         break;
 808                 case Opt_local_lock_none:
 809                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 810                                         NFS_MOUNT_LOCAL_FCNTL);
 811                         break;
 812                 default:
 813                         goto out_invalid_value;
 814                 }
 815                 break;
 816         case Opt_write:
 817                 switch (result.uint_32) {
 818                 case Opt_write_lazy:
 819                         ctx->flags &=
 820                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 821                         break;
 822                 case Opt_write_eager:
 823                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 824                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 825                         break;
 826                 case Opt_write_wait:
 827                         ctx->flags |=
 828                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 829                         break;
 830                 default:
 831                         goto out_invalid_value;
 832                 }
 833                 break;
 834
 835                 /*
 836                  * Special options
 837                  */
 838         case Opt_sloppy:
 839                 ctx->sloppy = true;
 840                 dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
 841                 break;
 842         }
 843
 844         return 0;
 845
 846 out_invalid_value:
 847         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 848 out_invalid_address:
 849         return nfs_invalf(fc, "NFS: Bad IP address specified");
 850 out_of_bounds:
 851         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 852 out_bad_transport:
 853         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 854 }
 855
 856 /*
 857  * Split fc->source into "hostname:export_path".
 858  *
 859  * The leftmost colon demarks the split between the server's hostname
 860  * and the export path.  If the hostname starts with a left square
 861  * bracket, then it may contain colons.
 862  *
 863  * Note: caller frees hostname and export path, even on error.
 864  */
 865 static int nfs_parse_source(struct fs_context *fc,
 866                             size_t maxnamlen, size_t maxpathlen)
 867 {
 868         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 869         const char *dev_name = fc->source;
 870         size_t len;
 871         const char *end;
 872
 873         if (unlikely(!dev_name || !*dev_name)) {
 874                 dfprintk(MOUNT, "NFS: device name not specified\n");
 875                 return -EINVAL;
 876         }
 877
 878         /* Is the host name protected with square brakcets? */
 879         if (*dev_name == '[') {
 880                 end = strchr(++dev_name, ']');
 881                 if (end == NULL || end[1] != ':')
 882                         goto out_bad_devname;
 883
 884                 len = end - dev_name;
 885                 end++;
 886         } else {
 887                 const char *comma;
 888
 889                 end = strchr(dev_name, ':');
 890                 if (end == NULL)
 891                         goto out_bad_devname;
 892                 len = end - dev_name;
 893
 894                 /* kill possible hostname list: not supported */
 895                 comma = memchr(dev_name, ',', len);
 896                 if (comma)
 897                         len = comma - dev_name;
 898         }
 899
 900         if (len > maxnamlen)
 901                 goto out_hostname;
 902
 903         kfree(ctx->nfs_server.hostname);
 904
 905         /* N.B. caller will free nfs_server.hostname in all cases */
 906         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 907         if (!ctx->nfs_server.hostname)
 908                 goto out_nomem;
 909         len = strlen(++end);
 910         if (len > maxpathlen)
 911                 goto out_path;
 912         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
 913         if (!ctx->nfs_server.export_path)
 914                 goto out_nomem;
 915
 916         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
 917         return 0;
 918
 919 out_bad_devname:
 920         return nfs_invalf(fc, "NFS: device name not in host:path format");
 921 out_nomem:
 922         nfs_errorf(fc, "NFS: not enough memory to parse device name");
 923         return -ENOMEM;
 924 out_hostname:
 925         nfs_errorf(fc, "NFS: server hostname too long");
 926         return -ENAMETOOLONG;
 927 out_path:
 928         nfs_errorf(fc, "NFS: export pathname too long");
 929         return -ENAMETOOLONG;
 930 }
 931
 932 static inline bool is_remount_fc(struct fs_context *fc)
 933 {
 934         return fc->root != NULL;
 935 }
 936
 937 /*
 938  * Parse monolithic NFS2/NFS3 mount data
 939  * - fills in the mount root filehandle
 940  *
 941  * For option strings, user space handles the following behaviors:
 942  *
 943  * + DNS: mapping server host name to IP address ("addr=" option)
 944  *
 945  * + failure mode: how to behave if a mount request can't be handled
 946  *   immediately ("fg/bg" option)
 947  *
 948  * + retry: how often to retry a mount request ("retry=" option)
 949  *
 950  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
 951  *   mountproto=tcp after mountproto=udp, and so on
 952  */
 953 static int nfs23_parse_monolithic(struct fs_context *fc,
 954                                   struct nfs_mount_data *data)
 955 {
 956         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 957         struct nfs_fh *mntfh = ctx->mntfh;
 958         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
 959         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
 960         int ret;
 961
 962         if (data == NULL)
 963                 goto out_no_data;
 964
 965         ctx->version = NFS_DEFAULT_VERSION;
 966         switch (data->version) {
 967         case 1:
 968                 data->namlen = 0;
 969                 fallthrough;
 970         case 2:
 971                 data->bsize = 0;
 972                 fallthrough;
 973         case 3:
 974                 if (data->flags & NFS_MOUNT_VER3)
 975                         goto out_no_v3;
 976                 data->root.size = NFS2_FHSIZE;
 977                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
 978                 /* Turn off security negotiation */
 979                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
 980                 fallthrough;
 981         case 4:
 982                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
 983                         goto out_no_sec;
 984                 fallthrough;
 985         case 5:
 986                 memset(data->context, 0, sizeof(data->context));
 987                 fallthrough;
 988         case 6:
 989                 if (data->flags & NFS_MOUNT_VER3) {
 990                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
 991                                 goto out_invalid_fh;
 992                         mntfh->size = data->root.size;
 993                         ctx->version = 3;
 994                 } else {
 995                         mntfh->size = NFS2_FHSIZE;
 996                         ctx->version = 2;
 997                 }
 998
 999
1000                 memcpy(mntfh->data, data->root.data, mntfh->size);
1001                 if (mntfh->size < sizeof(mntfh->data))
1002                         memset(mntfh->data + mntfh->size, 0,
1003                                sizeof(mntfh->data) - mntfh->size);
1004
1005                 /*
1006                  * for proto == XPRT_TRANSPORT_UDP, which is what uses
1007                  * to_exponential, implying shift: limit the shift value
1008                  * to BITS_PER_LONG (majortimeo is unsigned long)
1009                  */
1010                 if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1011                         if (data->retrans >= 64) /* shift value is too large */
1012                                 goto out_invalid_data;
1013
1014                 /*
1015                  * Translate to nfs_fs_context, which nfs_fill_super
1016                  * can deal with.
1017                  */
1018                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
1019                 ctx->flags      |= extra_flags;
1020                 ctx->rsize      = data->rsize;
1021                 ctx->wsize      = data->wsize;
1022                 ctx->timeo      = data->timeo;
1023                 ctx->retrans    = data->retrans;
1024                 ctx->acregmin   = data->acregmin;
1025                 ctx->acregmax   = data->acregmax;
1026                 ctx->acdirmin   = data->acdirmin;
1027                 ctx->acdirmax   = data->acdirmax;
1028                 ctx->need_mount = false;
1029
1030                 memcpy(sap, &data->addr, sizeof(data->addr));
1031                 ctx->nfs_server.addrlen = sizeof(data->addr);
1032                 ctx->nfs_server.port = ntohs(data->addr.sin_port);
1033                 if (sap->sa_family != AF_INET ||
1034                     !nfs_verify_server_address(sap))
1035                         goto out_no_address;
1036
1037                 if (!(data->flags & NFS_MOUNT_TCP))
1038                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1039                 /* N.B. caller will free nfs_server.hostname in all cases */
1040                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1041                 if (!ctx->nfs_server.hostname)
1042                         goto out_nomem;
1043
1044                 ctx->namlen             = data->namlen;
1045                 ctx->bsize              = data->bsize;
1046
1047                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1048                         ctx->selected_flavor = data->pseudoflavor;
1049                 else
1050                         ctx->selected_flavor = RPC_AUTH_UNIX;
1051
1052                 if (!(data->flags & NFS_MOUNT_NONLM))
1053                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1054                                          NFS_MOUNT_LOCAL_FCNTL);
1055                 else
1056                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1057                                         NFS_MOUNT_LOCAL_FCNTL);
1058
1059                 /*
1060                  * The legacy version 6 binary mount data from userspace has a
1061                  * field used only to transport selinux information into the
1062                  * kernel.  To continue to support that functionality we
1063                  * have a touch of selinux knowledge here in the NFS code. The
1064                  * userspace code converted context=blah to just blah so we are
1065                  * converting back to the full string selinux understands.
1066                  */
1067                 if (data->context[0]){
1068 #ifdef CONFIG_SECURITY_SELINUX
1069                         int ret;
1070
1071                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1072                         ret = vfs_parse_fs_string(fc, "context",
1073                                                   data->context, strlen(data->context));
1074                         if (ret < 0)
1075                                 return ret;
1076 #else
1077                         return -EINVAL;
1078 #endif
1079                 }
1080
1081                 break;
1082         default:
1083                 goto generic;
1084         }
1085
1086         ret = nfs_validate_transport_protocol(fc, ctx);
1087         if (ret)
1088                 return ret;
1089
1090         ctx->skip_reconfig_option_check = true;
1091         return 0;
1092
1093 generic:
1094         return generic_parse_monolithic(fc, data);
1095
1096 out_no_data:
1097         if (is_remount_fc(fc)) {
1098                 ctx->skip_reconfig_option_check = true;
1099                 return 0;
1100         }
1101         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1102
1103 out_no_v3:
1104         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1105
1106 out_no_sec:
1107         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1108
1109 out_nomem:
1110         dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
1111         return -ENOMEM;
1112
1113 out_no_address:
1114         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1115
1116 out_invalid_fh:
1117         return nfs_invalf(fc, "NFS: invalid root filehandle");
1118
1119 out_invalid_data:
1120         return nfs_invalf(fc, "NFS: invalid binary mount data");
1121 }
1122
1123 #if IS_ENABLED(CONFIG_NFS_V4)
1124 struct compat_nfs_string {
1125         compat_uint_t len;
1126         compat_uptr_t data;
1127 };
1128
1129 static inline void compat_nfs_string(struct nfs_string *dst,
1130                                      struct compat_nfs_string *src)
1131 {
1132         dst->data = compat_ptr(src->data);
1133         dst->len = src->len;
1134 }
1135
1136 struct compat_nfs4_mount_data_v1 {
1137         compat_int_t version;
1138         compat_int_t flags;
1139         compat_int_t rsize;
1140         compat_int_t wsize;
1141         compat_int_t timeo;
1142         compat_int_t retrans;
1143         compat_int_t acregmin;
1144         compat_int_t acregmax;
1145         compat_int_t acdirmin;
1146         compat_int_t acdirmax;
1147         struct compat_nfs_string client_addr;
1148         struct compat_nfs_string mnt_path;
1149         struct compat_nfs_string hostname;
1150         compat_uint_t host_addrlen;
1151         compat_uptr_t host_addr;
1152         compat_int_t proto;
1153         compat_int_t auth_flavourlen;
1154         compat_uptr_t auth_flavours;
1155 };
1156
1157 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1158 {
1159         struct compat_nfs4_mount_data_v1 *compat =
1160                         (struct compat_nfs4_mount_data_v1 *)data;
1161
1162         /* copy the fields backwards */
1163         data->auth_flavours = compat_ptr(compat->auth_flavours);
1164         data->auth_flavourlen = compat->auth_flavourlen;
1165         data->proto = compat->proto;
1166         data->host_addr = compat_ptr(compat->host_addr);
1167         data->host_addrlen = compat->host_addrlen;
1168         compat_nfs_string(&data->hostname, &compat->hostname);
1169         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1170         compat_nfs_string(&data->client_addr, &compat->client_addr);
1171         data->acdirmax = compat->acdirmax;
1172         data->acdirmin = compat->acdirmin;
1173         data->acregmax = compat->acregmax;
1174         data->acregmin = compat->acregmin;
1175         data->retrans = compat->retrans;
1176         data->timeo = compat->timeo;
1177         data->wsize = compat->wsize;
1178         data->rsize = compat->rsize;
1179         data->flags = compat->flags;
1180         data->version = compat->version;
1181 }
1182
1183 /*
1184  * Validate NFSv4 mount options
1185  */
1186 static int nfs4_parse_monolithic(struct fs_context *fc,
1187                                  struct nfs4_mount_data *data)
1188 {
1189         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1190         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1191         int ret;
1192         char *c;
1193
1194         if (!data) {
1195                 if (is_remount_fc(fc))
1196                         goto done;
1197                 return nfs_invalf(fc,
1198                         "NFS4: mount program didn't pass any mount data");
1199         }
1200
1201         ctx->version = 4;
1202
1203         if (data->version != 1)
1204                 return generic_parse_monolithic(fc, data);
1205
1206         if (in_compat_syscall())
1207                 nfs4_compat_mount_data_conv(data);
1208
1209         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1210                 goto out_no_address;
1211         if (data->host_addrlen == 0)
1212                 goto out_no_address;
1213         ctx->nfs_server.addrlen = data->host_addrlen;
1214         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1215                 return -EFAULT;
1216         if (!nfs_verify_server_address(sap))
1217                 goto out_no_address;
1218         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1219
1220         if (data->auth_flavourlen) {
1221                 rpc_authflavor_t pseudoflavor;
1222
1223                 if (data->auth_flavourlen > 1)
1224                         goto out_inval_auth;
1225                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1226                                    sizeof(pseudoflavor)))
1227                         return -EFAULT;
1228                 ctx->selected_flavor = pseudoflavor;
1229         } else {
1230                 ctx->selected_flavor = RPC_AUTH_UNIX;
1231         }
1232
1233         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1234         if (IS_ERR(c))
1235                 return PTR_ERR(c);
1236         ctx->nfs_server.hostname = c;
1237
1238         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1239         if (IS_ERR(c))
1240                 return PTR_ERR(c);
1241         ctx->nfs_server.export_path = c;
1242         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1243
1244         c = strndup_user(data->client_addr.data, 16);
1245         if (IS_ERR(c))
1246                 return PTR_ERR(c);
1247         ctx->client_address = c;
1248
1249         /*
1250          * Translate to nfs_fs_context, which nfs_fill_super
1251          * can deal with.
1252          */
1253
1254         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1255         ctx->rsize      = data->rsize;
1256         ctx->wsize      = data->wsize;
1257         ctx->timeo      = data->timeo;
1258         ctx->retrans    = data->retrans;
1259         ctx->acregmin   = data->acregmin;
1260         ctx->acregmax   = data->acregmax;
1261         ctx->acdirmin   = data->acdirmin;
1262         ctx->acdirmax   = data->acdirmax;
1263         ctx->nfs_server.protocol = data->proto;
1264         ret = nfs_validate_transport_protocol(fc, ctx);
1265         if (ret)
1266                 return ret;
1267 done:
1268         ctx->skip_reconfig_option_check = true;
1269         return 0;
1270
1271 out_inval_auth:
1272         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1273                       data->auth_flavourlen);
1274
1275 out_no_address:
1276         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1277 }
1278 #endif
1279
1280 /*
1281  * Parse a monolithic block of data from sys_mount().
1282  */
1283 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1284                                            void *data)
1285 {
1286         if (fc->fs_type == &nfs_fs_type)
1287                 return nfs23_parse_monolithic(fc, data);
1288
1289 #if IS_ENABLED(CONFIG_NFS_V4)
1290         if (fc->fs_type == &nfs4_fs_type)
1291                 return nfs4_parse_monolithic(fc, data);
1292 #endif
1293
1294         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1295 }
1296
1297 /*
1298  * Validate the preparsed information in the config.
1299  */
1300 static int nfs_fs_context_validate(struct fs_context *fc)
1301 {
1302         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1303         struct nfs_subversion *nfs_mod;
1304         struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1305         int max_namelen = PAGE_SIZE;
1306         int max_pathlen = NFS_MAXPATHLEN;
1307         int port = 0;
1308         int ret;
1309
1310         if (!fc->source)
1311                 goto out_no_device_name;
1312
1313         /* Check for sanity first. */
1314         if (ctx->minorversion && ctx->version != 4)
1315                 goto out_minorversion_mismatch;
1316
1317         if (ctx->options & NFS_OPTION_MIGRATION &&
1318             (ctx->version != 4 || ctx->minorversion != 0))
1319                 goto out_migration_misuse;
1320
1321         /* Verify that any proto=/mountproto= options match the address
1322          * families in the addr=/mountaddr= options.
1323          */
1324         if (ctx->protofamily != AF_UNSPEC &&
1325             ctx->protofamily != ctx->nfs_server.address.sa_family)
1326                 goto out_proto_mismatch;
1327
1328         if (ctx->mountfamily != AF_UNSPEC) {
1329                 if (ctx->mount_server.addrlen) {
1330                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1331                                 goto out_mountproto_mismatch;
1332                 } else {
1333                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1334                                 goto out_mountproto_mismatch;
1335                 }
1336         }
1337
1338         if (!nfs_verify_server_address(sap))
1339                 goto out_no_address;
1340
1341         ret = nfs_validate_transport_protocol(fc, ctx);
1342         if (ret)
1343                 return ret;
1344
1345         if (ctx->version == 4) {
1346                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1347                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1348                                 port = NFS_RDMA_PORT;
1349                         else
1350                                 port = NFS_PORT;
1351                         max_namelen = NFS4_MAXNAMLEN;
1352                         max_pathlen = NFS4_MAXPATHLEN;
1353                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1354                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1355                                         NFS_MOUNT_LOCAL_FCNTL);
1356                 } else {
1357                         goto out_v4_not_compiled;
1358                 }
1359         } else {
1360                 nfs_set_mount_transport_protocol(ctx);
1361                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1362                         port = NFS_RDMA_PORT;
1363         }
1364
1365         nfs_set_port(sap, &ctx->nfs_server.port, port);
1366
1367         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1368         if (ret < 0)
1369                 return ret;
1370
1371         /* Load the NFS protocol module if we haven't done so yet */
1372         if (!ctx->nfs_mod) {
1373                 nfs_mod = get_nfs_version(ctx->version);
1374                 if (IS_ERR(nfs_mod)) {
1375                         ret = PTR_ERR(nfs_mod);
1376                         goto out_version_unavailable;
1377                 }
1378                 ctx->nfs_mod = nfs_mod;
1379         }
1380
1381         /* Ensure the filesystem context has the correct fs_type */
1382         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1383                 module_put(fc->fs_type->owner);
1384                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1385                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1386         }
1387         return 0;
1388
1389 out_no_device_name:
1390         return nfs_invalf(fc, "NFS: Device name not specified");
1391 out_v4_not_compiled:
1392         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1393         return -EPROTONOSUPPORT;
1394 out_no_address:
1395         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1396 out_mountproto_mismatch:
1397         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1398 out_proto_mismatch:
1399         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1400 out_minorversion_mismatch:
1401         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1402                           ctx->version, ctx->minorversion);
1403 out_migration_misuse:
1404         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1405 out_version_unavailable:
1406         nfs_errorf(fc, "NFS: Version unavailable");
1407         return ret;
1408 }
1409
1410 /*
1411  * Create an NFS superblock by the appropriate method.
1412  */
1413 static int nfs_get_tree(struct fs_context *fc)
1414 {
1415         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1416         int err = nfs_fs_context_validate(fc);
1417
1418         if (err)
1419                 return err;
1420         if (!ctx->internal)
1421                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1422         else
1423                 return nfs_get_tree_common(fc);
1424 }
1425
1426 /*
1427  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1428  * it can't deal with resource pointers in the filesystem context, so we have
1429  * to do that.  We need to clear pointers, copy data or get extra refs as
1430  * appropriate.
1431  */
1432 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1433 {
1434         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1435
1436         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1437         if (!ctx)
1438                 return -ENOMEM;
1439
1440         ctx->mntfh = nfs_alloc_fhandle();
1441         if (!ctx->mntfh) {
1442                 kfree(ctx);
1443                 return -ENOMEM;
1444         }
1445         nfs_copy_fh(ctx->mntfh, src->mntfh);
1446
1447         __module_get(ctx->nfs_mod->owner);
1448         ctx->client_address             = NULL;
1449         ctx->mount_server.hostname      = NULL;
1450         ctx->nfs_server.export_path     = NULL;
1451         ctx->nfs_server.hostname        = NULL;
1452         ctx->fscache_uniq               = NULL;
1453         ctx->clone_data.fattr           = NULL;
1454         fc->fs_private = ctx;
1455         return 0;
1456 }
1457
1458 static void nfs_fs_context_free(struct fs_context *fc)
1459 {
1460         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1461
1462         if (ctx) {
1463                 if (ctx->server)
1464                         nfs_free_server(ctx->server);
1465                 if (ctx->nfs_mod)
1466                         put_nfs_version(ctx->nfs_mod);
1467                 kfree(ctx->client_address);
1468                 kfree(ctx->mount_server.hostname);
1469                 kfree(ctx->nfs_server.export_path);
1470                 kfree(ctx->nfs_server.hostname);
1471                 kfree(ctx->fscache_uniq);
1472                 nfs_free_fhandle(ctx->mntfh);
1473                 nfs_free_fattr(ctx->clone_data.fattr);
1474                 kfree(ctx);
1475         }
1476 }
1477
1478 static const struct fs_context_operations nfs_fs_context_ops = {
1479         .free                   = nfs_fs_context_free,
1480         .dup                    = nfs_fs_context_dup,
1481         .parse_param            = nfs_fs_context_parse_param,
1482         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1483         .get_tree               = nfs_get_tree,
1484         .reconfigure            = nfs_reconfigure,
1485 };
1486
1487 /*
1488  * Prepare superblock configuration.  We use the namespaces attached to the
1489  * context.  This may be the current process's namespaces, or it may be a
1490  * container's namespaces.
1491  */
1492 static int nfs_init_fs_context(struct fs_context *fc)
1493 {
1494         struct nfs_fs_context *ctx;
1495
1496         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1497         if (unlikely(!ctx))
1498                 return -ENOMEM;
1499
1500         ctx->mntfh = nfs_alloc_fhandle();
1501         if (unlikely(!ctx->mntfh)) {
1502                 kfree(ctx);
1503                 return -ENOMEM;
1504         }
1505
1506         ctx->protofamily        = AF_UNSPEC;
1507         ctx->mountfamily        = AF_UNSPEC;
1508         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1509
1510         if (fc->root) {
1511                 /* reconfigure, start with the current config */
1512                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1513                 struct net *net = nfss->nfs_client->cl_net;
1514
1515                 ctx->flags              = nfss->flags;
1516                 ctx->rsize              = nfss->rsize;
1517                 ctx->wsize              = nfss->wsize;
1518                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1519                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1520                 ctx->acregmin           = nfss->acregmin / HZ;
1521                 ctx->acregmax           = nfss->acregmax / HZ;
1522                 ctx->acdirmin           = nfss->acdirmin / HZ;
1523                 ctx->acdirmax           = nfss->acdirmax / HZ;
1524                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1525                 ctx->nfs_server.port    = nfss->port;
1526                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1527                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1528                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1529
1530                 memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
1531                         ctx->nfs_server.addrlen);
1532
1533                 if (fc->net_ns != net) {
1534                         put_net(fc->net_ns);
1535                         fc->net_ns = get_net(net);
1536                 }
1537
1538                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1539                 __module_get(ctx->nfs_mod->owner);
1540         } else {
1541                 /* defaults */
1542                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1543                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1544                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1545                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1546                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1547                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1548                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1549                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1550                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1551                 ctx->minorversion       = 0;
1552                 ctx->need_mount         = true;
1553
1554                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1555         }
1556         fc->fs_private = ctx;
1557         fc->ops = &nfs_fs_context_ops;
1558         return 0;
1559 }
1560
1561 struct file_system_type nfs_fs_type = {
1562         .owner                  = THIS_MODULE,
1563         .name                   = "nfs",
1564         .init_fs_context        = nfs_init_fs_context,
1565         .parameters             = nfs_fs_parameters,
1566         .kill_sb                = nfs_kill_super,
1567         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1568 };
1569 MODULE_ALIAS_FS("nfs");
1570 EXPORT_SYMBOL_GPL(nfs_fs_type);
1571
1572 #if IS_ENABLED(CONFIG_NFS_V4)
1573 struct file_system_type nfs4_fs_type = {
1574         .owner                  = THIS_MODULE,
1575         .name                   = "nfs4",
1576         .init_fs_context        = nfs_init_fs_context,
1577         .parameters             = nfs_fs_parameters,
1578         .kill_sb                = nfs_kill_super,
1579         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1580 };
1581 MODULE_ALIAS_FS("nfs4");
1582 MODULE_ALIAS("nfs4");
1583 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1584 #endif /* CONFIG_NFS_V4 */