fs/smb/client/connect.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002,2011
   5  *   Author(s): Steve French (sfrench@us.ibm.com)
   6  *
   7  */
   8 #include <linux/fs.h>
   9 #include <linux/net.h>
  10 #include <linux/string.h>
  11 #include <linux/sched/mm.h>
  12 #include <linux/sched/signal.h>
  13 #include <linux/list.h>
  14 #include <linux/wait.h>
  15 #include <linux/slab.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/ctype.h>
  18 #include <linux/utsname.h>
  19 #include <linux/mempool.h>
  20 #include <linux/delay.h>
  21 #include <linux/completion.h>
  22 #include <linux/kthread.h>
  23 #include <linux/pagevec.h>
  24 #include <linux/freezer.h>
  25 #include <linux/namei.h>
  26 #include <linux/uuid.h>
  27 #include <linux/uaccess.h>
  28 #include <asm/processor.h>
  29 #include <linux/inet.h>
  30 #include <linux/module.h>
  31 #include <keys/user-type.h>
  32 #include <net/ipv6.h>
  33 #include <linux/parser.h>
  34 #include <linux/bvec.h>
  35 #include "cifspdu.h"
  36 #include "cifsglob.h"
  37 #include "cifsproto.h"
  38 #include "cifs_unicode.h"
  39 #include "cifs_debug.h"
  40 #include "cifs_fs_sb.h"
  41 #include "ntlmssp.h"
  42 #include "nterr.h"
  43 #include "rfc1002pdu.h"
  44 #include "fscache.h"
  45 #include "smb2proto.h"
  46 #include "smbdirect.h"
  47 #include "dns_resolve.h"
  48 #ifdef CONFIG_CIFS_DFS_UPCALL
  49 #include "dfs.h"
  50 #include "dfs_cache.h"
  51 #endif
  52 #include "fs_context.h"
  53 #include "cifs_swn.h"
  54
  55 extern mempool_t *cifs_req_poolp;
  56 extern bool disable_legacy_dialects;
  57
  58 /* FIXME: should these be tunable? */
  59 #define TLINK_ERROR_EXPIRE      (1 * HZ)
  60 #define TLINK_IDLE_EXPIRE       (600 * HZ)
  61
  62 /* Drop the connection to not overload the server */
  63 #define MAX_STATUS_IO_TIMEOUT   5
  64
  65 static int ip_connect(struct TCP_Server_Info *server);
  66 static int generic_ip_connect(struct TCP_Server_Info *server);
  67 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
  68 static void cifs_prune_tlinks(struct work_struct *work);
  69
  70 /*
  71  * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
  72  * get their ip addresses changed at some point.
  73  *
  74  * This should be called with server->srv_mutex held.
  75  */
  76 static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
  77 {
  78         int rc;
  79         int len;
  80         char *unc;
  81         struct sockaddr_storage ss;
  82
  83         if (!server->hostname)
  84                 return -EINVAL;
  85
  86         /* if server hostname isn't populated, there's nothing to do here */
  87         if (server->hostname[0] == '\0')
  88                 return 0;
  89
  90         len = strlen(server->hostname) + 3;
  91
  92         unc = kmalloc(len, GFP_KERNEL);
  93         if (!unc) {
  94                 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
  95                 return -ENOMEM;
  96         }
  97         scnprintf(unc, len, "\\\\%s", server->hostname);
  98
  99         spin_lock(&server->srv_lock);
 100         ss = server->dstaddr;
 101         spin_unlock(&server->srv_lock);
 102
 103         rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, NULL);
 104         kfree(unc);
 105
 106         if (rc < 0) {
 107                 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
 108                          __func__, server->hostname, rc);
 109         } else {
 110                 spin_lock(&server->srv_lock);
 111                 memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
 112                 spin_unlock(&server->srv_lock);
 113                 rc = 0;
 114         }
 115
 116         return rc;
 117 }
 118
 119 static void smb2_query_server_interfaces(struct work_struct *work)
 120 {
 121         int rc;
 122         int xid;
 123         struct cifs_tcon *tcon = container_of(work,
 124                                         struct cifs_tcon,
 125                                         query_interfaces.work);
 126
 127         /*
 128          * query server network interfaces, in case they change
 129          */
 130         xid = get_xid();
 131         rc = SMB3_request_interfaces(xid, tcon, false);
 132         free_xid(xid);
 133
 134         if (rc) {
 135                 if (rc == -EOPNOTSUPP)
 136                         return;
 137
 138                 cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
 139                                 __func__, rc);
 140         }
 141
 142         queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
 143                            (SMB_INTERFACE_POLL_INTERVAL * HZ));
 144 }
 145
 146 /*
 147  * Update the tcpStatus for the server.
 148  * This is used to signal the cifsd thread to call cifs_reconnect
 149  * ONLY cifsd thread should call cifs_reconnect. For any other
 150  * thread, use this function
 151  *
 152  * @server: the tcp ses for which reconnect is needed
 153  * @all_channels: if this needs to be done for all channels
 154  */
 155 void
 156 cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
 157                                 bool all_channels)
 158 {
 159         struct TCP_Server_Info *pserver;
 160         struct cifs_ses *ses;
 161         int i;
 162
 163         /* If server is a channel, select the primary channel */
 164         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
 165
 166         /* if we need to signal just this channel */
 167         if (!all_channels) {
 168                 spin_lock(&server->srv_lock);
 169                 if (server->tcpStatus != CifsExiting)
 170                         server->tcpStatus = CifsNeedReconnect;
 171                 spin_unlock(&server->srv_lock);
 172                 return;
 173         }
 174
 175         spin_lock(&cifs_tcp_ses_lock);
 176         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 177                 spin_lock(&ses->chan_lock);
 178                 for (i = 0; i < ses->chan_count; i++) {
 179                         if (!ses->chans[i].server)
 180                                 continue;
 181
 182                         spin_lock(&ses->chans[i].server->srv_lock);
 183                         if (ses->chans[i].server->tcpStatus != CifsExiting)
 184                                 ses->chans[i].server->tcpStatus = CifsNeedReconnect;
 185                         spin_unlock(&ses->chans[i].server->srv_lock);
 186                 }
 187                 spin_unlock(&ses->chan_lock);
 188         }
 189         spin_unlock(&cifs_tcp_ses_lock);
 190 }
 191
 192 /*
 193  * Mark all sessions and tcons for reconnect.
 194  * IMPORTANT: make sure that this gets called only from
 195  * cifsd thread. For any other thread, use
 196  * cifs_signal_cifsd_for_reconnect
 197  *
 198  * @server: the tcp ses for which reconnect is needed
 199  * @server needs to be previously set to CifsNeedReconnect.
 200  * @mark_smb_session: whether even sessions need to be marked
 201  */
 202 void
 203 cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
 204                                       bool mark_smb_session)
 205 {
 206         struct TCP_Server_Info *pserver;
 207         struct cifs_ses *ses, *nses;
 208         struct cifs_tcon *tcon;
 209
 210         /*
 211          * before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
 212          * are not used until reconnected.
 213          */
 214         cifs_dbg(FYI, "%s: marking necessary sessions and tcons for reconnect\n", __func__);
 215
 216         /* If server is a channel, select the primary channel */
 217         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
 218
 219
 220         spin_lock(&cifs_tcp_ses_lock);
 221         list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
 222                 /*
 223                  * if channel has been marked for termination, nothing to do
 224                  * for the channel. in fact, we cannot find the channel for the
 225                  * server. So safe to exit here
 226                  */
 227                 if (server->terminate)
 228                         break;
 229
 230                 /* check if iface is still active */
 231                 if (!cifs_chan_is_iface_active(ses, server))
 232                         cifs_chan_update_iface(ses, server);
 233
 234                 spin_lock(&ses->chan_lock);
 235                 if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
 236                         spin_unlock(&ses->chan_lock);
 237                         continue;
 238                 }
 239
 240                 if (mark_smb_session)
 241                         CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses);
 242                 else
 243                         cifs_chan_set_need_reconnect(ses, server);
 244
 245                 cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
 246                          __func__, ses->chans_need_reconnect);
 247
 248                 /* If all channels need reconnect, then tcon needs reconnect */
 249                 if (!mark_smb_session && !CIFS_ALL_CHANS_NEED_RECONNECT(ses)) {
 250                         spin_unlock(&ses->chan_lock);
 251                         continue;
 252                 }
 253                 spin_unlock(&ses->chan_lock);
 254
 255                 spin_lock(&ses->ses_lock);
 256                 ses->ses_status = SES_NEED_RECON;
 257                 spin_unlock(&ses->ses_lock);
 258
 259                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 260                         tcon->need_reconnect = true;
 261                         spin_lock(&tcon->tc_lock);
 262                         tcon->status = TID_NEED_RECON;
 263                         spin_unlock(&tcon->tc_lock);
 264
 265                         cancel_delayed_work(&tcon->query_interfaces);
 266                 }
 267                 if (ses->tcon_ipc) {
 268                         ses->tcon_ipc->need_reconnect = true;
 269                         spin_lock(&ses->tcon_ipc->tc_lock);
 270                         ses->tcon_ipc->status = TID_NEED_RECON;
 271                         spin_unlock(&ses->tcon_ipc->tc_lock);
 272                 }
 273         }
 274         spin_unlock(&cifs_tcp_ses_lock);
 275 }
 276
 277 static void
 278 cifs_abort_connection(struct TCP_Server_Info *server)
 279 {
 280         struct mid_q_entry *mid, *nmid;
 281         struct list_head retry_list;
 282
 283         server->maxBuf = 0;
 284         server->max_read = 0;
 285
 286         /* do not want to be sending data on a socket we are freeing */
 287         cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
 288         cifs_server_lock(server);
 289         if (server->ssocket) {
 290                 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
 291                          server->ssocket->flags);
 292                 kernel_sock_shutdown(server->ssocket, SHUT_WR);
 293                 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
 294                          server->ssocket->flags);
 295                 sock_release(server->ssocket);
 296                 server->ssocket = NULL;
 297         }
 298         server->sequence_number = 0;
 299         server->session_estab = false;
 300         kfree_sensitive(server->session_key.response);
 301         server->session_key.response = NULL;
 302         server->session_key.len = 0;
 303         server->lstrp = jiffies;
 304
 305         /* mark submitted MIDs for retry and issue callback */
 306         INIT_LIST_HEAD(&retry_list);
 307         cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
 308         spin_lock(&server->mid_lock);
 309         list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
 310                 kref_get(&mid->refcount);
 311                 if (mid->mid_state == MID_REQUEST_SUBMITTED)
 312                         mid->mid_state = MID_RETRY_NEEDED;
 313                 list_move(&mid->qhead, &retry_list);
 314                 mid->mid_flags |= MID_DELETED;
 315         }
 316         spin_unlock(&server->mid_lock);
 317         cifs_server_unlock(server);
 318
 319         cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
 320         list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
 321                 list_del_init(&mid->qhead);
 322                 mid->callback(mid);
 323                 release_mid(mid);
 324         }
 325
 326         if (cifs_rdma_enabled(server)) {
 327                 cifs_server_lock(server);
 328                 smbd_destroy(server);
 329                 cifs_server_unlock(server);
 330         }
 331 }
 332
 333 static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
 334 {
 335         spin_lock(&server->srv_lock);
 336         server->nr_targets = num_targets;
 337         if (server->tcpStatus == CifsExiting) {
 338                 /* the demux thread will exit normally next time through the loop */
 339                 spin_unlock(&server->srv_lock);
 340                 wake_up(&server->response_q);
 341                 return false;
 342         }
 343
 344         cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
 345         trace_smb3_reconnect(server->CurrentMid, server->conn_id,
 346                              server->hostname);
 347         server->tcpStatus = CifsNeedReconnect;
 348
 349         spin_unlock(&server->srv_lock);
 350         return true;
 351 }
 352
 353 /*
 354  * cifs tcp session reconnection
 355  *
 356  * mark tcp session as reconnecting so temporarily locked
 357  * mark all smb sessions as reconnecting for tcp session
 358  * reconnect tcp session
 359  * wake up waiters on reconnection? - (not needed currently)
 360  *
 361  * if mark_smb_session is passed as true, unconditionally mark
 362  * the smb session (and tcon) for reconnect as well. This value
 363  * doesn't really matter for non-multichannel scenario.
 364  *
 365  */
 366 static int __cifs_reconnect(struct TCP_Server_Info *server,
 367                             bool mark_smb_session)
 368 {
 369         int rc = 0;
 370
 371         if (!cifs_tcp_ses_needs_reconnect(server, 1))
 372                 return 0;
 373
 374         cifs_mark_tcp_ses_conns_for_reconnect(server, mark_smb_session);
 375
 376         cifs_abort_connection(server);
 377
 378         do {
 379                 try_to_freeze();
 380                 cifs_server_lock(server);
 381
 382                 if (!cifs_swn_set_server_dstaddr(server)) {
 383                         /* resolve the hostname again to make sure that IP address is up-to-date */
 384                         rc = reconn_set_ipaddr_from_hostname(server);
 385                         cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
 386                 }
 387
 388                 if (cifs_rdma_enabled(server))
 389                         rc = smbd_reconnect(server);
 390                 else
 391                         rc = generic_ip_connect(server);
 392                 if (rc) {
 393                         cifs_server_unlock(server);
 394                         cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
 395                         msleep(3000);
 396                 } else {
 397                         atomic_inc(&tcpSesReconnectCount);
 398                         set_credits(server, 1);
 399                         spin_lock(&server->srv_lock);
 400                         if (server->tcpStatus != CifsExiting)
 401                                 server->tcpStatus = CifsNeedNegotiate;
 402                         spin_unlock(&server->srv_lock);
 403                         cifs_swn_reset_server_dstaddr(server);
 404                         cifs_server_unlock(server);
 405                         mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 406                 }
 407         } while (server->tcpStatus == CifsNeedReconnect);
 408
 409         spin_lock(&server->srv_lock);
 410         if (server->tcpStatus == CifsNeedNegotiate)
 411                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 412         spin_unlock(&server->srv_lock);
 413
 414         wake_up(&server->response_q);
 415         return rc;
 416 }
 417
 418 #ifdef CONFIG_CIFS_DFS_UPCALL
 419 static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
 420 {
 421         int rc;
 422         char *hostname;
 423
 424         if (!cifs_swn_set_server_dstaddr(server)) {
 425                 if (server->hostname != target) {
 426                         hostname = extract_hostname(target);
 427                         if (!IS_ERR(hostname)) {
 428                                 spin_lock(&server->srv_lock);
 429                                 kfree(server->hostname);
 430                                 server->hostname = hostname;
 431                                 spin_unlock(&server->srv_lock);
 432                         } else {
 433                                 cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
 434                                          __func__, PTR_ERR(hostname));
 435                                 cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
 436                                          server->hostname);
 437                         }
 438                 }
 439                 /* resolve the hostname again to make sure that IP address is up-to-date. */
 440                 rc = reconn_set_ipaddr_from_hostname(server);
 441                 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
 442         }
 443         /* Reconnect the socket */
 444         if (cifs_rdma_enabled(server))
 445                 rc = smbd_reconnect(server);
 446         else
 447                 rc = generic_ip_connect(server);
 448
 449         return rc;
 450 }
 451
 452 static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
 453                                      struct dfs_cache_tgt_iterator **target_hint)
 454 {
 455         int rc;
 456         struct dfs_cache_tgt_iterator *tit;
 457
 458         *target_hint = NULL;
 459
 460         /* If dfs target list is empty, then reconnect to last server */
 461         tit = dfs_cache_get_tgt_iterator(tl);
 462         if (!tit)
 463                 return __reconnect_target_unlocked(server, server->hostname);
 464
 465         /* Otherwise, try every dfs target in @tl */
 466         for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
 467                 rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
 468                 if (!rc) {
 469                         *target_hint = tit;
 470                         break;
 471                 }
 472         }
 473         return rc;
 474 }
 475
 476 static int reconnect_dfs_server(struct TCP_Server_Info *server)
 477 {
 478         struct dfs_cache_tgt_iterator *target_hint = NULL;
 479         DFS_CACHE_TGT_LIST(tl);
 480         int num_targets = 0;
 481         int rc = 0;
 482
 483         /*
 484          * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
 485          *
 486          * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
 487          * targets (server->nr_targets).  It's also possible that the cached referral was cleared
 488          * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
 489          * refreshing the referral, so, in this case, default it to 1.
 490          */
 491         mutex_lock(&server->refpath_lock);
 492         if (!dfs_cache_noreq_find(server->leaf_fullpath + 1, NULL, &tl))
 493                 num_targets = dfs_cache_get_nr_tgts(&tl);
 494         mutex_unlock(&server->refpath_lock);
 495         if (!num_targets)
 496                 num_targets = 1;
 497
 498         if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
 499                 return 0;
 500
 501         /*
 502          * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
 503          * different server or share during failover.  It could be improved by adding some logic to
 504          * only do that in case it connects to a different server or share, though.
 505          */
 506         cifs_mark_tcp_ses_conns_for_reconnect(server, true);
 507
 508         cifs_abort_connection(server);
 509
 510         do {
 511                 try_to_freeze();
 512                 cifs_server_lock(server);
 513
 514                 rc = reconnect_target_unlocked(server, &tl, &target_hint);
 515                 if (rc) {
 516                         /* Failed to reconnect socket */
 517                         cifs_server_unlock(server);
 518                         cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
 519                         msleep(3000);
 520                         continue;
 521                 }
 522                 /*
 523                  * Socket was created.  Update tcp session status to CifsNeedNegotiate so that a
 524                  * process waiting for reconnect will know it needs to re-establish session and tcon
 525                  * through the reconnected target server.
 526                  */
 527                 atomic_inc(&tcpSesReconnectCount);
 528                 set_credits(server, 1);
 529                 spin_lock(&server->srv_lock);
 530                 if (server->tcpStatus != CifsExiting)
 531                         server->tcpStatus = CifsNeedNegotiate;
 532                 spin_unlock(&server->srv_lock);
 533                 cifs_swn_reset_server_dstaddr(server);
 534                 cifs_server_unlock(server);
 535                 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 536         } while (server->tcpStatus == CifsNeedReconnect);
 537
 538         mutex_lock(&server->refpath_lock);
 539         dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, target_hint);
 540         mutex_unlock(&server->refpath_lock);
 541         dfs_cache_free_tgts(&tl);
 542
 543         /* Need to set up echo worker again once connection has been established */
 544         spin_lock(&server->srv_lock);
 545         if (server->tcpStatus == CifsNeedNegotiate)
 546                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 547         spin_unlock(&server->srv_lock);
 548
 549         wake_up(&server->response_q);
 550         return rc;
 551 }
 552
 553 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 554 {
 555         mutex_lock(&server->refpath_lock);
 556         if (!server->leaf_fullpath) {
 557                 mutex_unlock(&server->refpath_lock);
 558                 return __cifs_reconnect(server, mark_smb_session);
 559         }
 560         mutex_unlock(&server->refpath_lock);
 561
 562         return reconnect_dfs_server(server);
 563 }
 564 #else
 565 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 566 {
 567         return __cifs_reconnect(server, mark_smb_session);
 568 }
 569 #endif
 570
 571 static void
 572 cifs_echo_request(struct work_struct *work)
 573 {
 574         int rc;
 575         struct TCP_Server_Info *server = container_of(work,
 576                                         struct TCP_Server_Info, echo.work);
 577
 578         /*
 579          * We cannot send an echo if it is disabled.
 580          * Also, no need to ping if we got a response recently.
 581          */
 582
 583         if (server->tcpStatus == CifsNeedReconnect ||
 584             server->tcpStatus == CifsExiting ||
 585             server->tcpStatus == CifsNew ||
 586             (server->ops->can_echo && !server->ops->can_echo(server)) ||
 587             time_before(jiffies, server->lstrp + server->echo_interval - HZ))
 588                 goto requeue_echo;
 589
 590         rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
 591         cifs_server_dbg(FYI, "send echo request: rc = %d\n", rc);
 592
 593         /* Check witness registrations */
 594         cifs_swn_check();
 595
 596 requeue_echo:
 597         queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
 598 }
 599
 600 static bool
 601 allocate_buffers(struct TCP_Server_Info *server)
 602 {
 603         if (!server->bigbuf) {
 604                 server->bigbuf = (char *)cifs_buf_get();
 605                 if (!server->bigbuf) {
 606                         cifs_server_dbg(VFS, "No memory for large SMB response\n");
 607                         msleep(3000);
 608                         /* retry will check if exiting */
 609                         return false;
 610                 }
 611         } else if (server->large_buf) {
 612                 /* we are reusing a dirty large buf, clear its start */
 613                 memset(server->bigbuf, 0, HEADER_SIZE(server));
 614         }
 615
 616         if (!server->smallbuf) {
 617                 server->smallbuf = (char *)cifs_small_buf_get();
 618                 if (!server->smallbuf) {
 619                         cifs_server_dbg(VFS, "No memory for SMB response\n");
 620                         msleep(1000);
 621                         /* retry will check if exiting */
 622                         return false;
 623                 }
 624                 /* beginning of smb buffer is cleared in our buf_get */
 625         } else {
 626                 /* if existing small buf clear beginning */
 627                 memset(server->smallbuf, 0, HEADER_SIZE(server));
 628         }
 629
 630         return true;
 631 }
 632
 633 static bool
 634 server_unresponsive(struct TCP_Server_Info *server)
 635 {
 636         /*
 637          * We need to wait 3 echo intervals to make sure we handle such
 638          * situations right:
 639          * 1s  client sends a normal SMB request
 640          * 2s  client gets a response
 641          * 30s echo workqueue job pops, and decides we got a response recently
 642          *     and don't need to send another
 643          * ...
 644          * 65s kernel_recvmsg times out, and we see that we haven't gotten
 645          *     a response in >60s.
 646          */
 647         spin_lock(&server->srv_lock);
 648         if ((server->tcpStatus == CifsGood ||
 649             server->tcpStatus == CifsNeedNegotiate) &&
 650             (!server->ops->can_echo || server->ops->can_echo(server)) &&
 651             time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
 652                 spin_unlock(&server->srv_lock);
 653                 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
 654                          (3 * server->echo_interval) / HZ);
 655                 cifs_reconnect(server, false);
 656                 return true;
 657         }
 658         spin_unlock(&server->srv_lock);
 659
 660         return false;
 661 }
 662
 663 static inline bool
 664 zero_credits(struct TCP_Server_Info *server)
 665 {
 666         int val;
 667
 668         spin_lock(&server->req_lock);
 669         val = server->credits + server->echo_credits + server->oplock_credits;
 670         if (server->in_flight == 0 && val == 0) {
 671                 spin_unlock(&server->req_lock);
 672                 return true;
 673         }
 674         spin_unlock(&server->req_lock);
 675         return false;
 676 }
 677
 678 static int
 679 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 680 {
 681         int length = 0;
 682         int total_read;
 683
 684         for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 685                 try_to_freeze();
 686
 687                 /* reconnect if no credits and no requests in flight */
 688                 if (zero_credits(server)) {
 689                         cifs_reconnect(server, false);
 690                         return -ECONNABORTED;
 691                 }
 692
 693                 if (server_unresponsive(server))
 694                         return -ECONNABORTED;
 695                 if (cifs_rdma_enabled(server) && server->smbd_conn)
 696                         length = smbd_recv(server->smbd_conn, smb_msg);
 697                 else
 698                         length = sock_recvmsg(server->ssocket, smb_msg, 0);
 699
 700                 spin_lock(&server->srv_lock);
 701                 if (server->tcpStatus == CifsExiting) {
 702                         spin_unlock(&server->srv_lock);
 703                         return -ESHUTDOWN;
 704                 }
 705
 706                 if (server->tcpStatus == CifsNeedReconnect) {
 707                         spin_unlock(&server->srv_lock);
 708                         cifs_reconnect(server, false);
 709                         return -ECONNABORTED;
 710                 }
 711                 spin_unlock(&server->srv_lock);
 712
 713                 if (length == -ERESTARTSYS ||
 714                     length == -EAGAIN ||
 715                     length == -EINTR) {
 716                         /*
 717                          * Minimum sleep to prevent looping, allowing socket
 718                          * to clear and app threads to set tcpStatus
 719                          * CifsNeedReconnect if server hung.
 720                          */
 721                         usleep_range(1000, 2000);
 722                         length = 0;
 723                         continue;
 724                 }
 725
 726                 if (length <= 0) {
 727                         cifs_dbg(FYI, "Received no data or error: %d\n", length);
 728                         cifs_reconnect(server, false);
 729                         return -ECONNABORTED;
 730                 }
 731         }
 732         return total_read;
 733 }
 734
 735 int
 736 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 737                       unsigned int to_read)
 738 {
 739         struct msghdr smb_msg = {};
 740         struct kvec iov = {.iov_base = buf, .iov_len = to_read};
 741         iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
 742
 743         return cifs_readv_from_socket(server, &smb_msg);
 744 }
 745
 746 ssize_t
 747 cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
 748 {
 749         struct msghdr smb_msg = {};
 750
 751         /*
 752          *  iov_iter_discard already sets smb_msg.type and count and iov_offset
 753          *  and cifs_readv_from_socket sets msg_control and msg_controllen
 754          *  so little to initialize in struct msghdr
 755          */
 756         iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
 757
 758         return cifs_readv_from_socket(server, &smb_msg);
 759 }
 760
 761 int
 762 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 763         unsigned int page_offset, unsigned int to_read)
 764 {
 765         struct msghdr smb_msg = {};
 766         struct bio_vec bv;
 767
 768         bvec_set_page(&bv, page, to_read, page_offset);
 769         iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
 770         return cifs_readv_from_socket(server, &smb_msg);
 771 }
 772
 773 int
 774 cifs_read_iter_from_socket(struct TCP_Server_Info *server, struct iov_iter *iter,
 775                            unsigned int to_read)
 776 {
 777         struct msghdr smb_msg = { .msg_iter = *iter };
 778         int ret;
 779
 780         iov_iter_truncate(&smb_msg.msg_iter, to_read);
 781         ret = cifs_readv_from_socket(server, &smb_msg);
 782         if (ret > 0)
 783                 iov_iter_advance(iter, ret);
 784         return ret;
 785 }
 786
 787 static bool
 788 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
 789 {
 790         /*
 791          * The first byte big endian of the length field,
 792          * is actually not part of the length but the type
 793          * with the most common, zero, as regular data.
 794          */
 795         switch (type) {
 796         case RFC1002_SESSION_MESSAGE:
 797                 /* Regular SMB response */
 798                 return true;
 799         case RFC1002_SESSION_KEEP_ALIVE:
 800                 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
 801                 break;
 802         case RFC1002_POSITIVE_SESSION_RESPONSE:
 803                 cifs_dbg(FYI, "RFC 1002 positive session response\n");
 804                 break;
 805         case RFC1002_NEGATIVE_SESSION_RESPONSE:
 806                 /*
 807                  * We get this from Windows 98 instead of an error on
 808                  * SMB negprot response.
 809                  */
 810                 cifs_dbg(FYI, "RFC 1002 negative session response\n");
 811                 /* give server a second to clean up */
 812                 msleep(1000);
 813                 /*
 814                  * Always try 445 first on reconnect since we get NACK
 815                  * on some if we ever connected to port 139 (the NACK
 816                  * is since we do not begin with RFC1001 session
 817                  * initialize frame).
 818                  */
 819                 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
 820                 cifs_reconnect(server, true);
 821                 break;
 822         default:
 823                 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
 824                 cifs_reconnect(server, true);
 825         }
 826
 827         return false;
 828 }
 829
 830 void
 831 dequeue_mid(struct mid_q_entry *mid, bool malformed)
 832 {
 833 #ifdef CONFIG_CIFS_STATS2
 834         mid->when_received = jiffies;
 835 #endif
 836         spin_lock(&mid->server->mid_lock);
 837         if (!malformed)
 838                 mid->mid_state = MID_RESPONSE_RECEIVED;
 839         else
 840                 mid->mid_state = MID_RESPONSE_MALFORMED;
 841         /*
 842          * Trying to handle/dequeue a mid after the send_recv()
 843          * function has finished processing it is a bug.
 844          */
 845         if (mid->mid_flags & MID_DELETED) {
 846                 spin_unlock(&mid->server->mid_lock);
 847                 pr_warn_once("trying to dequeue a deleted mid\n");
 848         } else {
 849                 list_del_init(&mid->qhead);
 850                 mid->mid_flags |= MID_DELETED;
 851                 spin_unlock(&mid->server->mid_lock);
 852         }
 853 }
 854
 855 static unsigned int
 856 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 857 {
 858         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
 859
 860         /*
 861          * SMB1 does not use credits.
 862          */
 863         if (is_smb1(server))
 864                 return 0;
 865
 866         return le16_to_cpu(shdr->CreditRequest);
 867 }
 868
 869 static void
 870 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 871            char *buf, int malformed)
 872 {
 873         if (server->ops->check_trans2 &&
 874             server->ops->check_trans2(mid, server, buf, malformed))
 875                 return;
 876         mid->credits_received = smb2_get_credits_from_hdr(buf, server);
 877         mid->resp_buf = buf;
 878         mid->large_buf = server->large_buf;
 879         /* Was previous buf put in mpx struct for multi-rsp? */
 880         if (!mid->multiRsp) {
 881                 /* smb buffer will be freed by user thread */
 882                 if (server->large_buf)
 883                         server->bigbuf = NULL;
 884                 else
 885                         server->smallbuf = NULL;
 886         }
 887         dequeue_mid(mid, malformed);
 888 }
 889
 890 int
 891 cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
 892 {
 893         bool srv_sign_required = server->sec_mode & server->vals->signing_required;
 894         bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
 895         bool mnt_sign_enabled;
 896
 897         /*
 898          * Is signing required by mnt options? If not then check
 899          * global_secflags to see if it is there.
 900          */
 901         if (!mnt_sign_required)
 902                 mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
 903                                                 CIFSSEC_MUST_SIGN);
 904
 905         /*
 906          * If signing is required then it's automatically enabled too,
 907          * otherwise, check to see if the secflags allow it.
 908          */
 909         mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
 910                                 (global_secflags & CIFSSEC_MAY_SIGN);
 911
 912         /* If server requires signing, does client allow it? */
 913         if (srv_sign_required) {
 914                 if (!mnt_sign_enabled) {
 915                         cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
 916                         return -EOPNOTSUPP;
 917                 }
 918                 server->sign = true;
 919         }
 920
 921         /* If client requires signing, does server allow it? */
 922         if (mnt_sign_required) {
 923                 if (!srv_sign_enabled) {
 924                         cifs_dbg(VFS, "Server does not support signing!\n");
 925                         return -EOPNOTSUPP;
 926                 }
 927                 server->sign = true;
 928         }
 929
 930         if (cifs_rdma_enabled(server) && server->sign)
 931                 cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
 932
 933         return 0;
 934 }
 935
 936 static noinline_for_stack void
 937 clean_demultiplex_info(struct TCP_Server_Info *server)
 938 {
 939         int length;
 940
 941         /* take it off the list, if it's not already */
 942         spin_lock(&server->srv_lock);
 943         list_del_init(&server->tcp_ses_list);
 944         spin_unlock(&server->srv_lock);
 945
 946         cancel_delayed_work_sync(&server->echo);
 947
 948         spin_lock(&server->srv_lock);
 949         server->tcpStatus = CifsExiting;
 950         spin_unlock(&server->srv_lock);
 951         wake_up_all(&server->response_q);
 952
 953         /* check if we have blocked requests that need to free */
 954         spin_lock(&server->req_lock);
 955         if (server->credits <= 0)
 956                 server->credits = 1;
 957         spin_unlock(&server->req_lock);
 958         /*
 959          * Although there should not be any requests blocked on this queue it
 960          * can not hurt to be paranoid and try to wake up requests that may
 961          * haven been blocked when more than 50 at time were on the wire to the
 962          * same server - they now will see the session is in exit state and get
 963          * out of SendReceive.
 964          */
 965         wake_up_all(&server->request_q);
 966         /* give those requests time to exit */
 967         msleep(125);
 968         if (cifs_rdma_enabled(server))
 969                 smbd_destroy(server);
 970         if (server->ssocket) {
 971                 sock_release(server->ssocket);
 972                 server->ssocket = NULL;
 973         }
 974
 975         if (!list_empty(&server->pending_mid_q)) {
 976                 struct list_head dispose_list;
 977                 struct mid_q_entry *mid_entry;
 978                 struct list_head *tmp, *tmp2;
 979
 980                 INIT_LIST_HEAD(&dispose_list);
 981                 spin_lock(&server->mid_lock);
 982                 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 983                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 984                         cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
 985                         kref_get(&mid_entry->refcount);
 986                         mid_entry->mid_state = MID_SHUTDOWN;
 987                         list_move(&mid_entry->qhead, &dispose_list);
 988                         mid_entry->mid_flags |= MID_DELETED;
 989                 }
 990                 spin_unlock(&server->mid_lock);
 991
 992                 /* now walk dispose list and issue callbacks */
 993                 list_for_each_safe(tmp, tmp2, &dispose_list) {
 994                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 995                         cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
 996                         list_del_init(&mid_entry->qhead);
 997                         mid_entry->callback(mid_entry);
 998                         release_mid(mid_entry);
 999                 }
1000                 /* 1/8th of sec is more than enough time for them to exit */
1001                 msleep(125);
1002         }
1003
1004         if (!list_empty(&server->pending_mid_q)) {
1005                 /*
1006                  * mpx threads have not exited yet give them at least the smb
1007                  * send timeout time for long ops.
1008                  *
1009                  * Due to delays on oplock break requests, we need to wait at
1010                  * least 45 seconds before giving up on a request getting a
1011                  * response and going ahead and killing cifsd.
1012                  */
1013                 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
1014                 msleep(46000);
1015                 /*
1016                  * If threads still have not exited they are probably never
1017                  * coming home not much else we can do but free the memory.
1018                  */
1019         }
1020
1021         kfree(server->leaf_fullpath);
1022         kfree(server);
1023
1024         length = atomic_dec_return(&tcpSesAllocCount);
1025         if (length > 0)
1026                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1027 }
1028
1029 static int
1030 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1031 {
1032         int length;
1033         char *buf = server->smallbuf;
1034         unsigned int pdu_length = server->pdu_size;
1035
1036         /* make sure this will fit in a large buffer */
1037         if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1038             HEADER_PREAMBLE_SIZE(server)) {
1039                 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1040                 cifs_reconnect(server, true);
1041                 return -ECONNABORTED;
1042         }
1043
1044         /* switch to large buffer if too big for a small one */
1045         if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1046                 server->large_buf = true;
1047                 memcpy(server->bigbuf, buf, server->total_read);
1048                 buf = server->bigbuf;
1049         }
1050
1051         /* now read the rest */
1052         length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1053                                        pdu_length - MID_HEADER_SIZE(server));
1054
1055         if (length < 0)
1056                 return length;
1057         server->total_read += length;
1058
1059         dump_smb(buf, server->total_read);
1060
1061         return cifs_handle_standard(server, mid);
1062 }
1063
1064 int
1065 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1066 {
1067         char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1068         int rc;
1069
1070         /*
1071          * We know that we received enough to get to the MID as we
1072          * checked the pdu_length earlier. Now check to see
1073          * if the rest of the header is OK.
1074          *
1075          * 48 bytes is enough to display the header and a little bit
1076          * into the payload for debugging purposes.
1077          */
1078         rc = server->ops->check_message(buf, server->total_read, server);
1079         if (rc)
1080                 cifs_dump_mem("Bad SMB: ", buf,
1081                         min_t(unsigned int, server->total_read, 48));
1082
1083         if (server->ops->is_session_expired &&
1084             server->ops->is_session_expired(buf)) {
1085                 cifs_reconnect(server, true);
1086                 return -1;
1087         }
1088
1089         if (server->ops->is_status_pending &&
1090             server->ops->is_status_pending(buf, server))
1091                 return -1;
1092
1093         if (!mid)
1094                 return rc;
1095
1096         handle_mid(mid, server, buf, rc);
1097         return 0;
1098 }
1099
1100 static void
1101 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1102 {
1103         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
1104         int scredits, in_flight;
1105
1106         /*
1107          * SMB1 does not use credits.
1108          */
1109         if (is_smb1(server))
1110                 return;
1111
1112         if (shdr->CreditRequest) {
1113                 spin_lock(&server->req_lock);
1114                 server->credits += le16_to_cpu(shdr->CreditRequest);
1115                 scredits = server->credits;
1116                 in_flight = server->in_flight;
1117                 spin_unlock(&server->req_lock);
1118                 wake_up(&server->request_q);
1119
1120                 trace_smb3_hdr_credits(server->CurrentMid,
1121                                 server->conn_id, server->hostname, scredits,
1122                                 le16_to_cpu(shdr->CreditRequest), in_flight);
1123                 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
1124                                 __func__, le16_to_cpu(shdr->CreditRequest),
1125                                 scredits);
1126         }
1127 }
1128
1129
1130 static int
1131 cifs_demultiplex_thread(void *p)
1132 {
1133         int i, num_mids, length;
1134         struct TCP_Server_Info *server = p;
1135         unsigned int pdu_length;
1136         unsigned int next_offset;
1137         char *buf = NULL;
1138         struct task_struct *task_to_wake = NULL;
1139         struct mid_q_entry *mids[MAX_COMPOUND];
1140         char *bufs[MAX_COMPOUND];
1141         unsigned int noreclaim_flag, num_io_timeout = 0;
1142         bool pending_reconnect = false;
1143
1144         noreclaim_flag = memalloc_noreclaim_save();
1145         cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1146
1147         length = atomic_inc_return(&tcpSesAllocCount);
1148         if (length > 1)
1149                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1150
1151         set_freezable();
1152         allow_kernel_signal(SIGKILL);
1153         while (server->tcpStatus != CifsExiting) {
1154                 if (try_to_freeze())
1155                         continue;
1156
1157                 if (!allocate_buffers(server))
1158                         continue;
1159
1160                 server->large_buf = false;
1161                 buf = server->smallbuf;
1162                 pdu_length = 4; /* enough to get RFC1001 header */
1163
1164                 length = cifs_read_from_socket(server, buf, pdu_length);
1165                 if (length < 0)
1166                         continue;
1167
1168                 if (is_smb1(server))
1169                         server->total_read = length;
1170                 else
1171                         server->total_read = 0;
1172
1173                 /*
1174                  * The right amount was read from socket - 4 bytes,
1175                  * so we can now interpret the length field.
1176                  */
1177                 pdu_length = get_rfc1002_length(buf);
1178
1179                 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1180                 if (!is_smb_response(server, buf[0]))
1181                         continue;
1182
1183                 pending_reconnect = false;
1184 next_pdu:
1185                 server->pdu_size = pdu_length;
1186
1187                 /* make sure we have enough to get to the MID */
1188                 if (server->pdu_size < MID_HEADER_SIZE(server)) {
1189                         cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1190                                  server->pdu_size);
1191                         cifs_reconnect(server, true);
1192                         continue;
1193                 }
1194
1195                 /* read down to the MID */
1196                 length = cifs_read_from_socket(server,
1197                              buf + HEADER_PREAMBLE_SIZE(server),
1198                              MID_HEADER_SIZE(server));
1199                 if (length < 0)
1200                         continue;
1201                 server->total_read += length;
1202
1203                 if (server->ops->next_header) {
1204                         if (server->ops->next_header(server, buf, &next_offset)) {
1205                                 cifs_dbg(VFS, "%s: malformed response (next_offset=%u)\n",
1206                                          __func__, next_offset);
1207                                 cifs_reconnect(server, true);
1208                                 continue;
1209                         }
1210                         if (next_offset)
1211                                 server->pdu_size = next_offset;
1212                 }
1213
1214                 memset(mids, 0, sizeof(mids));
1215                 memset(bufs, 0, sizeof(bufs));
1216                 num_mids = 0;
1217
1218                 if (server->ops->is_transform_hdr &&
1219                     server->ops->receive_transform &&
1220                     server->ops->is_transform_hdr(buf)) {
1221                         length = server->ops->receive_transform(server,
1222                                                                 mids,
1223                                                                 bufs,
1224                                                                 &num_mids);
1225                 } else {
1226                         mids[0] = server->ops->find_mid(server, buf);
1227                         bufs[0] = buf;
1228                         num_mids = 1;
1229
1230                         if (!mids[0] || !mids[0]->receive)
1231                                 length = standard_receive3(server, mids[0]);
1232                         else
1233                                 length = mids[0]->receive(server, mids[0]);
1234                 }
1235
1236                 if (length < 0) {
1237                         for (i = 0; i < num_mids; i++)
1238                                 if (mids[i])
1239                                         release_mid(mids[i]);
1240                         continue;
1241                 }
1242
1243                 if (server->ops->is_status_io_timeout &&
1244                     server->ops->is_status_io_timeout(buf)) {
1245                         num_io_timeout++;
1246                         if (num_io_timeout > MAX_STATUS_IO_TIMEOUT) {
1247                                 cifs_server_dbg(VFS,
1248                                                 "Number of request timeouts exceeded %d. Reconnecting",
1249                                                 MAX_STATUS_IO_TIMEOUT);
1250
1251                                 pending_reconnect = true;
1252                                 num_io_timeout = 0;
1253                         }
1254                 }
1255
1256                 server->lstrp = jiffies;
1257
1258                 for (i = 0; i < num_mids; i++) {
1259                         if (mids[i] != NULL) {
1260                                 mids[i]->resp_buf_size = server->pdu_size;
1261
1262                                 if (bufs[i] != NULL) {
1263                                         if (server->ops->is_network_name_deleted &&
1264                                             server->ops->is_network_name_deleted(bufs[i],
1265                                                                                  server)) {
1266                                                 cifs_server_dbg(FYI,
1267                                                                 "Share deleted. Reconnect needed");
1268                                         }
1269                                 }
1270
1271                                 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1272                                         mids[i]->callback(mids[i]);
1273
1274                                 release_mid(mids[i]);
1275                         } else if (server->ops->is_oplock_break &&
1276                                    server->ops->is_oplock_break(bufs[i],
1277                                                                 server)) {
1278                                 smb2_add_credits_from_hdr(bufs[i], server);
1279                                 cifs_dbg(FYI, "Received oplock break\n");
1280                         } else {
1281                                 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1282                                                 atomic_read(&mid_count));
1283                                 cifs_dump_mem("Received Data is: ", bufs[i],
1284                                               HEADER_SIZE(server));
1285                                 smb2_add_credits_from_hdr(bufs[i], server);
1286 #ifdef CONFIG_CIFS_DEBUG2
1287                                 if (server->ops->dump_detail)
1288                                         server->ops->dump_detail(bufs[i],
1289                                                                  server);
1290                                 cifs_dump_mids(server);
1291 #endif /* CIFS_DEBUG2 */
1292                         }
1293                 }
1294
1295                 if (pdu_length > server->pdu_size) {
1296                         if (!allocate_buffers(server))
1297                                 continue;
1298                         pdu_length -= server->pdu_size;
1299                         server->total_read = 0;
1300                         server->large_buf = false;
1301                         buf = server->smallbuf;
1302                         goto next_pdu;
1303                 }
1304
1305                 /* do this reconnect at the very end after processing all MIDs */
1306                 if (pending_reconnect)
1307                         cifs_reconnect(server, true);
1308
1309         } /* end while !EXITING */
1310
1311         /* buffer usually freed in free_mid - need to free it here on exit */
1312         cifs_buf_release(server->bigbuf);
1313         if (server->smallbuf) /* no sense logging a debug message if NULL */
1314                 cifs_small_buf_release(server->smallbuf);
1315
1316         task_to_wake = xchg(&server->tsk, NULL);
1317         clean_demultiplex_info(server);
1318
1319         /* if server->tsk was NULL then wait for a signal before exiting */
1320         if (!task_to_wake) {
1321                 set_current_state(TASK_INTERRUPTIBLE);
1322                 while (!signal_pending(current)) {
1323                         schedule();
1324                         set_current_state(TASK_INTERRUPTIBLE);
1325                 }
1326                 set_current_state(TASK_RUNNING);
1327         }
1328
1329         memalloc_noreclaim_restore(noreclaim_flag);
1330         module_put_and_kthread_exit(0);
1331 }
1332
1333 int
1334 cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
1335 {
1336         struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1337         struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1338         struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1339         struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1340
1341         switch (srcaddr->sa_family) {
1342         case AF_UNSPEC:
1343                 switch (rhs->sa_family) {
1344                 case AF_UNSPEC:
1345                         return 0;
1346                 case AF_INET:
1347                 case AF_INET6:
1348                         return 1;
1349                 default:
1350                         return -1;
1351                 }
1352         case AF_INET: {
1353                 switch (rhs->sa_family) {
1354                 case AF_UNSPEC:
1355                         return -1;
1356                 case AF_INET:
1357                         return memcmp(saddr4, vaddr4,
1358                                       sizeof(struct sockaddr_in));
1359                 case AF_INET6:
1360                         return 1;
1361                 default:
1362                         return -1;
1363                 }
1364         }
1365         case AF_INET6: {
1366                 switch (rhs->sa_family) {
1367                 case AF_UNSPEC:
1368                 case AF_INET:
1369                         return -1;
1370                 case AF_INET6:
1371                         return memcmp(saddr6,
1372                                       vaddr6,
1373                                       sizeof(struct sockaddr_in6));
1374                 default:
1375                         return -1;
1376                 }
1377         }
1378         default:
1379                 return -1; /* don't expect to be here */
1380         }
1381 }
1382
1383 /*
1384  * Returns true if srcaddr isn't specified and rhs isn't specified, or
1385  * if srcaddr is specified and matches the IP address of the rhs argument
1386  */
1387 bool
1388 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1389 {
1390         switch (srcaddr->sa_family) {
1391         case AF_UNSPEC:
1392                 return (rhs->sa_family == AF_UNSPEC);
1393         case AF_INET: {
1394                 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1395                 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1396                 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1397         }
1398         case AF_INET6: {
1399                 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1400                 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1401                 return (ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr)
1402                         && saddr6->sin6_scope_id == vaddr6->sin6_scope_id);
1403         }
1404         default:
1405                 WARN_ON(1);
1406                 return false; /* don't expect to be here */
1407         }
1408 }
1409
1410 /*
1411  * If no port is specified in addr structure, we try to match with 445 port
1412  * and if it fails - with 139 ports. It should be called only if address
1413  * families of server and addr are equal.
1414  */
1415 static bool
1416 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1417 {
1418         __be16 port, *sport;
1419
1420         /* SMBDirect manages its own ports, don't match it here */
1421         if (server->rdma)
1422                 return true;
1423
1424         switch (addr->sa_family) {
1425         case AF_INET:
1426                 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1427                 port = ((struct sockaddr_in *) addr)->sin_port;
1428                 break;
1429         case AF_INET6:
1430                 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1431                 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1432                 break;
1433         default:
1434                 WARN_ON(1);
1435                 return false;
1436         }
1437
1438         if (!port) {
1439                 port = htons(CIFS_PORT);
1440                 if (port == *sport)
1441                         return true;
1442
1443                 port = htons(RFC1001_PORT);
1444         }
1445
1446         return port == *sport;
1447 }
1448
1449 static bool match_server_address(struct TCP_Server_Info *server, struct sockaddr *addr)
1450 {
1451         if (!cifs_match_ipaddr(addr, (struct sockaddr *)&server->dstaddr))
1452                 return false;
1453
1454         return true;
1455 }
1456
1457 static bool
1458 match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1459 {
1460         /*
1461          * The select_sectype function should either return the ctx->sectype
1462          * that was specified, or "Unspecified" if that sectype was not
1463          * compatible with the given NEGOTIATE request.
1464          */
1465         if (server->ops->select_sectype(server, ctx->sectype)
1466              == Unspecified)
1467                 return false;
1468
1469         /*
1470          * Now check if signing mode is acceptable. No need to check
1471          * global_secflags at this point since if MUST_SIGN is set then
1472          * the server->sign had better be too.
1473          */
1474         if (ctx->sign && !server->sign)
1475                 return false;
1476
1477         return true;
1478 }
1479
1480 /* this function must be called with srv_lock held */
1481 static int match_server(struct TCP_Server_Info *server,
1482                         struct smb3_fs_context *ctx,
1483                         bool match_super)
1484 {
1485         struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1486
1487         lockdep_assert_held(&server->srv_lock);
1488
1489         if (ctx->nosharesock)
1490                 return 0;
1491
1492         /* this server does not share socket */
1493         if (server->nosharesock)
1494                 return 0;
1495
1496         /* If multidialect negotiation see if existing sessions match one */
1497         if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1498                 if (server->vals->protocol_id < SMB30_PROT_ID)
1499                         return 0;
1500         } else if (strcmp(ctx->vals->version_string,
1501                    SMBDEFAULT_VERSION_STRING) == 0) {
1502                 if (server->vals->protocol_id < SMB21_PROT_ID)
1503                         return 0;
1504         } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1505                 return 0;
1506
1507         if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1508                 return 0;
1509
1510         if (!cifs_match_ipaddr((struct sockaddr *)&ctx->srcaddr,
1511                                (struct sockaddr *)&server->srcaddr))
1512                 return 0;
1513         /*
1514          * When matching cifs.ko superblocks (@match_super == true), we can't
1515          * really match either @server->leaf_fullpath or @server->dstaddr
1516          * directly since this @server might belong to a completely different
1517          * server -- in case of domain-based DFS referrals or DFS links -- as
1518          * provided earlier by mount(2) through 'source' and 'ip' options.
1519          *
1520          * Otherwise, match the DFS referral in @server->leaf_fullpath or the
1521          * destination address in @server->dstaddr.
1522          *
1523          * When using 'nodfs' mount option, we avoid sharing it with DFS
1524          * connections as they might failover.
1525          */
1526         if (!match_super) {
1527                 if (!ctx->nodfs) {
1528                         if (server->leaf_fullpath) {
1529                                 if (!ctx->leaf_fullpath ||
1530                                     strcasecmp(server->leaf_fullpath,
1531                                                ctx->leaf_fullpath))
1532                                         return 0;
1533                         } else if (ctx->leaf_fullpath) {
1534                                 return 0;
1535                         }
1536                 } else if (server->leaf_fullpath) {
1537                         return 0;
1538                 }
1539         }
1540
1541         /*
1542          * Match for a regular connection (address/hostname/port) which has no
1543          * DFS referrals set.
1544          */
1545         if (!server->leaf_fullpath &&
1546             (strcasecmp(server->hostname, ctx->server_hostname) ||
1547              !match_server_address(server, addr) ||
1548              !match_port(server, addr)))
1549                 return 0;
1550
1551         if (!match_security(server, ctx))
1552                 return 0;
1553
1554         if (server->echo_interval != ctx->echo_interval * HZ)
1555                 return 0;
1556
1557         if (server->rdma != ctx->rdma)
1558                 return 0;
1559
1560         if (server->ignore_signature != ctx->ignore_signature)
1561                 return 0;
1562
1563         if (server->min_offload != ctx->min_offload)
1564                 return 0;
1565
1566         return 1;
1567 }
1568
1569 struct TCP_Server_Info *
1570 cifs_find_tcp_session(struct smb3_fs_context *ctx)
1571 {
1572         struct TCP_Server_Info *server;
1573
1574         spin_lock(&cifs_tcp_ses_lock);
1575         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1576                 spin_lock(&server->srv_lock);
1577                 /*
1578                  * Skip ses channels since they're only handled in lower layers
1579                  * (e.g. cifs_send_recv).
1580                  */
1581                 if (SERVER_IS_CHAN(server) ||
1582                     !match_server(server, ctx, false)) {
1583                         spin_unlock(&server->srv_lock);
1584                         continue;
1585                 }
1586                 spin_unlock(&server->srv_lock);
1587
1588                 ++server->srv_count;
1589                 spin_unlock(&cifs_tcp_ses_lock);
1590                 cifs_dbg(FYI, "Existing tcp session with server found\n");
1591                 return server;
1592         }
1593         spin_unlock(&cifs_tcp_ses_lock);
1594         return NULL;
1595 }
1596
1597 void
1598 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1599 {
1600         struct task_struct *task;
1601
1602         spin_lock(&cifs_tcp_ses_lock);
1603         if (--server->srv_count > 0) {
1604                 spin_unlock(&cifs_tcp_ses_lock);
1605                 return;
1606         }
1607
1608         /* srv_count can never go negative */
1609         WARN_ON(server->srv_count < 0);
1610
1611         put_net(cifs_net_ns(server));
1612
1613         list_del_init(&server->tcp_ses_list);
1614         spin_unlock(&cifs_tcp_ses_lock);
1615
1616         cancel_delayed_work_sync(&server->echo);
1617
1618         if (from_reconnect)
1619                 /*
1620                  * Avoid deadlock here: reconnect work calls
1621                  * cifs_put_tcp_session() at its end. Need to be sure
1622                  * that reconnect work does nothing with server pointer after
1623                  * that step.
1624                  */
1625                 cancel_delayed_work(&server->reconnect);
1626         else
1627                 cancel_delayed_work_sync(&server->reconnect);
1628
1629         /* For secondary channels, we pick up ref-count on the primary server */
1630         if (SERVER_IS_CHAN(server))
1631                 cifs_put_tcp_session(server->primary_server, from_reconnect);
1632
1633         spin_lock(&server->srv_lock);
1634         server->tcpStatus = CifsExiting;
1635         spin_unlock(&server->srv_lock);
1636
1637         cifs_crypto_secmech_release(server);
1638
1639         kfree_sensitive(server->session_key.response);
1640         server->session_key.response = NULL;
1641         server->session_key.len = 0;
1642         kfree(server->hostname);
1643         server->hostname = NULL;
1644
1645         task = xchg(&server->tsk, NULL);
1646         if (task)
1647                 send_sig(SIGKILL, task, 1);
1648 }
1649
1650 struct TCP_Server_Info *
1651 cifs_get_tcp_session(struct smb3_fs_context *ctx,
1652                      struct TCP_Server_Info *primary_server)
1653 {
1654         struct TCP_Server_Info *tcp_ses = NULL;
1655         int rc;
1656
1657         cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1658
1659         /* see if we already have a matching tcp_ses */
1660         tcp_ses = cifs_find_tcp_session(ctx);
1661         if (tcp_ses)
1662                 return tcp_ses;
1663
1664         tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1665         if (!tcp_ses) {
1666                 rc = -ENOMEM;
1667                 goto out_err;
1668         }
1669
1670         tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
1671         if (!tcp_ses->hostname) {
1672                 rc = -ENOMEM;
1673                 goto out_err;
1674         }
1675
1676         if (ctx->leaf_fullpath) {
1677                 tcp_ses->leaf_fullpath = kstrdup(ctx->leaf_fullpath, GFP_KERNEL);
1678                 if (!tcp_ses->leaf_fullpath) {
1679                         rc = -ENOMEM;
1680                         goto out_err;
1681                 }
1682         }
1683
1684         if (ctx->nosharesock)
1685                 tcp_ses->nosharesock = true;
1686
1687         tcp_ses->ops = ctx->ops;
1688         tcp_ses->vals = ctx->vals;
1689         cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1690
1691         tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1692         tcp_ses->noblockcnt = ctx->rootfs;
1693         tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1694         tcp_ses->noautotune = ctx->noautotune;
1695         tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1696         tcp_ses->rdma = ctx->rdma;
1697         tcp_ses->in_flight = 0;
1698         tcp_ses->max_in_flight = 0;
1699         tcp_ses->credits = 1;
1700         if (primary_server) {
1701                 spin_lock(&cifs_tcp_ses_lock);
1702                 ++primary_server->srv_count;
1703                 spin_unlock(&cifs_tcp_ses_lock);
1704                 tcp_ses->primary_server = primary_server;
1705         }
1706         init_waitqueue_head(&tcp_ses->response_q);
1707         init_waitqueue_head(&tcp_ses->request_q);
1708         INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1709         mutex_init(&tcp_ses->_srv_mutex);
1710         memcpy(tcp_ses->workstation_RFC1001_name,
1711                 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1712         memcpy(tcp_ses->server_RFC1001_name,
1713                 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1714         tcp_ses->session_estab = false;
1715         tcp_ses->sequence_number = 0;
1716         tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
1717         tcp_ses->reconnect_instance = 1;
1718         tcp_ses->lstrp = jiffies;
1719         tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1720         spin_lock_init(&tcp_ses->req_lock);
1721         spin_lock_init(&tcp_ses->srv_lock);
1722         spin_lock_init(&tcp_ses->mid_lock);
1723         INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1724         INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1725         INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1726         INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1727         mutex_init(&tcp_ses->reconnect_mutex);
1728 #ifdef CONFIG_CIFS_DFS_UPCALL
1729         mutex_init(&tcp_ses->refpath_lock);
1730 #endif
1731         memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1732                sizeof(tcp_ses->srcaddr));
1733         memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1734                 sizeof(tcp_ses->dstaddr));
1735         if (ctx->use_client_guid)
1736                 memcpy(tcp_ses->client_guid, ctx->client_guid,
1737                        SMB2_CLIENT_GUID_SIZE);
1738         else
1739                 generate_random_uuid(tcp_ses->client_guid);
1740         /*
1741          * at this point we are the only ones with the pointer
1742          * to the struct since the kernel thread not created yet
1743          * no need to spinlock this init of tcpStatus or srv_count
1744          */
1745         tcp_ses->tcpStatus = CifsNew;
1746         ++tcp_ses->srv_count;
1747
1748         if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1749                 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1750                 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1751         else
1752                 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1753         if (tcp_ses->rdma) {
1754 #ifndef CONFIG_CIFS_SMB_DIRECT
1755                 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1756                 rc = -ENOENT;
1757                 goto out_err_crypto_release;
1758 #endif
1759                 tcp_ses->smbd_conn = smbd_get_connection(
1760                         tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1761                 if (tcp_ses->smbd_conn) {
1762                         cifs_dbg(VFS, "RDMA transport established\n");
1763                         rc = 0;
1764                         goto smbd_connected;
1765                 } else {
1766                         rc = -ENOENT;
1767                         goto out_err_crypto_release;
1768                 }
1769         }
1770         rc = ip_connect(tcp_ses);
1771         if (rc < 0) {
1772                 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1773                 goto out_err_crypto_release;
1774         }
1775 smbd_connected:
1776         /*
1777          * since we're in a cifs function already, we know that
1778          * this will succeed. No need for try_module_get().
1779          */
1780         __module_get(THIS_MODULE);
1781         tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1782                                   tcp_ses, "cifsd");
1783         if (IS_ERR(tcp_ses->tsk)) {
1784                 rc = PTR_ERR(tcp_ses->tsk);
1785                 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1786                 module_put(THIS_MODULE);
1787                 goto out_err_crypto_release;
1788         }
1789         tcp_ses->min_offload = ctx->min_offload;
1790         /*
1791          * at this point we are the only ones with the pointer
1792          * to the struct since the kernel thread not created yet
1793          * no need to spinlock this update of tcpStatus
1794          */
1795         spin_lock(&tcp_ses->srv_lock);
1796         tcp_ses->tcpStatus = CifsNeedNegotiate;
1797         spin_unlock(&tcp_ses->srv_lock);
1798
1799         if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1800                 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1801         else
1802                 tcp_ses->max_credits = ctx->max_credits;
1803
1804         tcp_ses->nr_targets = 1;
1805         tcp_ses->ignore_signature = ctx->ignore_signature;
1806         /* thread spawned, put it on the list */
1807         spin_lock(&cifs_tcp_ses_lock);
1808         list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1809         spin_unlock(&cifs_tcp_ses_lock);
1810
1811         /* queue echo request delayed work */
1812         queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1813
1814         return tcp_ses;
1815
1816 out_err_crypto_release:
1817         cifs_crypto_secmech_release(tcp_ses);
1818
1819         put_net(cifs_net_ns(tcp_ses));
1820
1821 out_err:
1822         if (tcp_ses) {
1823                 if (SERVER_IS_CHAN(tcp_ses))
1824                         cifs_put_tcp_session(tcp_ses->primary_server, false);
1825                 kfree(tcp_ses->hostname);
1826                 kfree(tcp_ses->leaf_fullpath);
1827                 if (tcp_ses->ssocket)
1828                         sock_release(tcp_ses->ssocket);
1829                 kfree(tcp_ses);
1830         }
1831         return ERR_PTR(rc);
1832 }
1833
1834 /* this function must be called with ses_lock and chan_lock held */
1835 static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1836 {
1837         if (ctx->sectype != Unspecified &&
1838             ctx->sectype != ses->sectype)
1839                 return 0;
1840
1841         /*
1842          * If an existing session is limited to less channels than
1843          * requested, it should not be reused
1844          */
1845         if (ses->chan_max < ctx->max_channels)
1846                 return 0;
1847
1848         switch (ses->sectype) {
1849         case Kerberos:
1850                 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1851                         return 0;
1852                 break;
1853         default:
1854                 /* NULL username means anonymous session */
1855                 if (ses->user_name == NULL) {
1856                         if (!ctx->nullauth)
1857                                 return 0;
1858                         break;
1859                 }
1860
1861                 /* anything else takes username/password */
1862                 if (strncmp(ses->user_name,
1863                             ctx->username ? ctx->username : "",
1864                             CIFS_MAX_USERNAME_LEN))
1865                         return 0;
1866                 if ((ctx->username && strlen(ctx->username) != 0) &&
1867                     ses->password != NULL &&
1868                     strncmp(ses->password,
1869                             ctx->password ? ctx->password : "",
1870                             CIFS_MAX_PASSWORD_LEN))
1871                         return 0;
1872         }
1873
1874         if (strcmp(ctx->local_nls->charset, ses->local_nls->charset))
1875                 return 0;
1876
1877         return 1;
1878 }
1879
1880 /**
1881  * cifs_setup_ipc - helper to setup the IPC tcon for the session
1882  * @ses: smb session to issue the request on
1883  * @ctx: the superblock configuration context to use for building the
1884  *       new tree connection for the IPC (interprocess communication RPC)
1885  *
1886  * A new IPC connection is made and stored in the session
1887  * tcon_ipc. The IPC tcon has the same lifetime as the session.
1888  */
1889 static int
1890 cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1891 {
1892         int rc = 0, xid;
1893         struct cifs_tcon *tcon;
1894         char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1895         bool seal = false;
1896         struct TCP_Server_Info *server = ses->server;
1897
1898         /*
1899          * If the mount request that resulted in the creation of the
1900          * session requires encryption, force IPC to be encrypted too.
1901          */
1902         if (ctx->seal) {
1903                 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1904                         seal = true;
1905                 else {
1906                         cifs_server_dbg(VFS,
1907                                  "IPC: server doesn't support encryption\n");
1908                         return -EOPNOTSUPP;
1909                 }
1910         }
1911
1912         /* no need to setup directory caching on IPC share, so pass in false */
1913         tcon = tcon_info_alloc(false);
1914         if (tcon == NULL)
1915                 return -ENOMEM;
1916
1917         spin_lock(&server->srv_lock);
1918         scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1919         spin_unlock(&server->srv_lock);
1920
1921         xid = get_xid();
1922         tcon->ses = ses;
1923         tcon->ipc = true;
1924         tcon->seal = seal;
1925         rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1926         free_xid(xid);
1927
1928         if (rc) {
1929                 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1930                 tconInfoFree(tcon);
1931                 goto out;
1932         }
1933
1934         cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
1935
1936         spin_lock(&tcon->tc_lock);
1937         tcon->status = TID_GOOD;
1938         spin_unlock(&tcon->tc_lock);
1939         ses->tcon_ipc = tcon;
1940 out:
1941         return rc;
1942 }
1943
1944 /**
1945  * cifs_free_ipc - helper to release the session IPC tcon
1946  * @ses: smb session to unmount the IPC from
1947  *
1948  * Needs to be called everytime a session is destroyed.
1949  *
1950  * On session close, the IPC is closed and the server must release all tcons of the session.
1951  * No need to send a tree disconnect here.
1952  *
1953  * Besides, it will make the server to not close durable and resilient files on session close, as
1954  * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1955  */
1956 static int
1957 cifs_free_ipc(struct cifs_ses *ses)
1958 {
1959         struct cifs_tcon *tcon = ses->tcon_ipc;
1960
1961         if (tcon == NULL)
1962                 return 0;
1963
1964         tconInfoFree(tcon);
1965         ses->tcon_ipc = NULL;
1966         return 0;
1967 }
1968
1969 static struct cifs_ses *
1970 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1971 {
1972         struct cifs_ses *ses, *ret = NULL;
1973
1974         spin_lock(&cifs_tcp_ses_lock);
1975         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1976                 spin_lock(&ses->ses_lock);
1977                 if (ses->ses_status == SES_EXITING) {
1978                         spin_unlock(&ses->ses_lock);
1979                         continue;
1980                 }
1981                 spin_lock(&ses->chan_lock);
1982                 if (match_session(ses, ctx)) {
1983                         spin_unlock(&ses->chan_lock);
1984                         spin_unlock(&ses->ses_lock);
1985                         ret = ses;
1986                         break;
1987                 }
1988                 spin_unlock(&ses->chan_lock);
1989                 spin_unlock(&ses->ses_lock);
1990         }
1991         if (ret)
1992                 cifs_smb_ses_inc_refcount(ret);
1993         spin_unlock(&cifs_tcp_ses_lock);
1994         return ret;
1995 }
1996
1997 void __cifs_put_smb_ses(struct cifs_ses *ses)
1998 {
1999         struct TCP_Server_Info *server = ses->server;
2000         unsigned int xid;
2001         size_t i;
2002         int rc;
2003
2004         spin_lock(&ses->ses_lock);
2005         if (ses->ses_status == SES_EXITING) {
2006                 spin_unlock(&ses->ses_lock);
2007                 return;
2008         }
2009         spin_unlock(&ses->ses_lock);
2010
2011         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
2012         cifs_dbg(FYI,
2013                  "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
2014
2015         spin_lock(&cifs_tcp_ses_lock);
2016         if (--ses->ses_count > 0) {
2017                 spin_unlock(&cifs_tcp_ses_lock);
2018                 return;
2019         }
2020         spin_lock(&ses->ses_lock);
2021         if (ses->ses_status == SES_GOOD)
2022                 ses->ses_status = SES_EXITING;
2023         spin_unlock(&ses->ses_lock);
2024         spin_unlock(&cifs_tcp_ses_lock);
2025
2026         /* ses_count can never go negative */
2027         WARN_ON(ses->ses_count < 0);
2028
2029         spin_lock(&ses->ses_lock);
2030         if (ses->ses_status == SES_EXITING && server->ops->logoff) {
2031                 spin_unlock(&ses->ses_lock);
2032                 cifs_free_ipc(ses);
2033                 xid = get_xid();
2034                 rc = server->ops->logoff(xid, ses);
2035                 if (rc)
2036                         cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
2037                                 __func__, rc);
2038                 _free_xid(xid);
2039         } else {
2040                 spin_unlock(&ses->ses_lock);
2041                 cifs_free_ipc(ses);
2042         }
2043
2044         spin_lock(&cifs_tcp_ses_lock);
2045         list_del_init(&ses->smb_ses_list);
2046         spin_unlock(&cifs_tcp_ses_lock);
2047
2048         /* close any extra channels */
2049         for (i = 1; i < ses->chan_count; i++) {
2050                 if (ses->chans[i].iface) {
2051                         kref_put(&ses->chans[i].iface->refcount, release_iface);
2052                         ses->chans[i].iface = NULL;
2053                 }
2054                 cifs_put_tcp_session(ses->chans[i].server, 0);
2055                 ses->chans[i].server = NULL;
2056         }
2057
2058         /* we now account for primary channel in iface->refcount */
2059         if (ses->chans[0].iface) {
2060                 kref_put(&ses->chans[0].iface->refcount, release_iface);
2061                 ses->chans[0].server = NULL;
2062         }
2063
2064         sesInfoFree(ses);
2065         cifs_put_tcp_session(server, 0);
2066 }
2067
2068 #ifdef CONFIG_KEYS
2069
2070 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
2071 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
2072
2073 /* Populate username and pw fields from keyring if possible */
2074 static int
2075 cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
2076 {
2077         int rc = 0;
2078         int is_domain = 0;
2079         const char *delim, *payload;
2080         char *desc;
2081         ssize_t len;
2082         struct key *key;
2083         struct TCP_Server_Info *server = ses->server;
2084         struct sockaddr_in *sa;
2085         struct sockaddr_in6 *sa6;
2086         const struct user_key_payload *upayload;
2087
2088         desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
2089         if (!desc)
2090                 return -ENOMEM;
2091
2092         /* try to find an address key first */
2093         switch (server->dstaddr.ss_family) {
2094         case AF_INET:
2095                 sa = (struct sockaddr_in *)&server->dstaddr;
2096                 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
2097                 break;
2098         case AF_INET6:
2099                 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
2100                 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
2101                 break;
2102         default:
2103                 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
2104                          server->dstaddr.ss_family);
2105                 rc = -EINVAL;
2106                 goto out_err;
2107         }
2108
2109         cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2110         key = request_key(&key_type_logon, desc, "");
2111         if (IS_ERR(key)) {
2112                 if (!ses->domainName) {
2113                         cifs_dbg(FYI, "domainName is NULL\n");
2114                         rc = PTR_ERR(key);
2115                         goto out_err;
2116                 }
2117
2118                 /* didn't work, try to find a domain key */
2119                 sprintf(desc, "cifs:d:%s", ses->domainName);
2120                 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2121                 key = request_key(&key_type_logon, desc, "");
2122                 if (IS_ERR(key)) {
2123                         rc = PTR_ERR(key);
2124                         goto out_err;
2125                 }
2126                 is_domain = 1;
2127         }
2128
2129         down_read(&key->sem);
2130         upayload = user_key_payload_locked(key);
2131         if (IS_ERR_OR_NULL(upayload)) {
2132                 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
2133                 goto out_key_put;
2134         }
2135
2136         /* find first : in payload */
2137         payload = upayload->data;
2138         delim = strnchr(payload, upayload->datalen, ':');
2139         cifs_dbg(FYI, "payload=%s\n", payload);
2140         if (!delim) {
2141                 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
2142                          upayload->datalen);
2143                 rc = -EINVAL;
2144                 goto out_key_put;
2145         }
2146
2147         len = delim - payload;
2148         if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
2149                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
2150                          len);
2151                 rc = -EINVAL;
2152                 goto out_key_put;
2153         }
2154
2155         ctx->username = kstrndup(payload, len, GFP_KERNEL);
2156         if (!ctx->username) {
2157                 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
2158                          len);
2159                 rc = -ENOMEM;
2160                 goto out_key_put;
2161         }
2162         cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
2163
2164         len = key->datalen - (len + 1);
2165         if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
2166                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
2167                 rc = -EINVAL;
2168                 kfree(ctx->username);
2169                 ctx->username = NULL;
2170                 goto out_key_put;
2171         }
2172
2173         ++delim;
2174         ctx->password = kstrndup(delim, len, GFP_KERNEL);
2175         if (!ctx->password) {
2176                 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
2177                          len);
2178                 rc = -ENOMEM;
2179                 kfree(ctx->username);
2180                 ctx->username = NULL;
2181                 goto out_key_put;
2182         }
2183
2184         /*
2185          * If we have a domain key then we must set the domainName in the
2186          * for the request.
2187          */
2188         if (is_domain && ses->domainName) {
2189                 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
2190                 if (!ctx->domainname) {
2191                         cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
2192                                  len);
2193                         rc = -ENOMEM;
2194                         kfree(ctx->username);
2195                         ctx->username = NULL;
2196                         kfree_sensitive(ctx->password);
2197                         ctx->password = NULL;
2198                         goto out_key_put;
2199                 }
2200         }
2201
2202         strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
2203
2204 out_key_put:
2205         up_read(&key->sem);
2206         key_put(key);
2207 out_err:
2208         kfree(desc);
2209         cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
2210         return rc;
2211 }
2212 #else /* ! CONFIG_KEYS */
2213 static inline int
2214 cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
2215                    struct cifs_ses *ses __attribute__((unused)))
2216 {
2217         return -ENOSYS;
2218 }
2219 #endif /* CONFIG_KEYS */
2220
2221 /**
2222  * cifs_get_smb_ses - get a session matching @ctx data from @server
2223  * @server: server to setup the session to
2224  * @ctx: superblock configuration context to use to setup the session
2225  *
2226  * This function assumes it is being called from cifs_mount() where we
2227  * already got a server reference (server refcount +1). See
2228  * cifs_get_tcon() for refcount explanations.
2229  */
2230 struct cifs_ses *
2231 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
2232 {
2233         int rc = 0;
2234         unsigned int xid;
2235         struct cifs_ses *ses;
2236         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2237         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2238
2239         xid = get_xid();
2240
2241         ses = cifs_find_smb_ses(server, ctx);
2242         if (ses) {
2243                 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
2244                          ses->ses_status);
2245
2246                 spin_lock(&ses->chan_lock);
2247                 if (cifs_chan_needs_reconnect(ses, server)) {
2248                         spin_unlock(&ses->chan_lock);
2249                         cifs_dbg(FYI, "Session needs reconnect\n");
2250
2251                         mutex_lock(&ses->session_mutex);
2252                         rc = cifs_negotiate_protocol(xid, ses, server);
2253                         if (rc) {
2254                                 mutex_unlock(&ses->session_mutex);
2255                                 /* problem -- put our ses reference */
2256                                 cifs_put_smb_ses(ses);
2257                                 free_xid(xid);
2258                                 return ERR_PTR(rc);
2259                         }
2260
2261                         rc = cifs_setup_session(xid, ses, server,
2262                                                 ctx->local_nls);
2263                         if (rc) {
2264                                 mutex_unlock(&ses->session_mutex);
2265                                 /* problem -- put our reference */
2266                                 cifs_put_smb_ses(ses);
2267                                 free_xid(xid);
2268                                 return ERR_PTR(rc);
2269                         }
2270                         mutex_unlock(&ses->session_mutex);
2271
2272                         spin_lock(&ses->chan_lock);
2273                 }
2274                 spin_unlock(&ses->chan_lock);
2275
2276                 /* existing SMB ses has a server reference already */
2277                 cifs_put_tcp_session(server, 0);
2278                 free_xid(xid);
2279                 return ses;
2280         }
2281
2282         rc = -ENOMEM;
2283
2284         cifs_dbg(FYI, "Existing smb sess not found\n");
2285         ses = sesInfoAlloc();
2286         if (ses == NULL)
2287                 goto get_ses_fail;
2288
2289         /* new SMB session uses our server ref */
2290         ses->server = server;
2291         if (server->dstaddr.ss_family == AF_INET6)
2292                 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
2293         else
2294                 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
2295
2296         if (ctx->username) {
2297                 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
2298                 if (!ses->user_name)
2299                         goto get_ses_fail;
2300         }
2301
2302         /* ctx->password freed at unmount */
2303         if (ctx->password) {
2304                 ses->password = kstrdup(ctx->password, GFP_KERNEL);
2305                 if (!ses->password)
2306                         goto get_ses_fail;
2307         }
2308         if (ctx->domainname) {
2309                 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
2310                 if (!ses->domainName)
2311                         goto get_ses_fail;
2312         }
2313
2314         strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
2315
2316         if (ctx->domainauto)
2317                 ses->domainAuto = ctx->domainauto;
2318         ses->cred_uid = ctx->cred_uid;
2319         ses->linux_uid = ctx->linux_uid;
2320
2321         ses->sectype = ctx->sectype;
2322         ses->sign = ctx->sign;
2323         ses->local_nls = load_nls(ctx->local_nls->charset);
2324
2325         /* add server as first channel */
2326         spin_lock(&ses->chan_lock);
2327         ses->chans[0].server = server;
2328         ses->chan_count = 1;
2329         ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
2330         ses->chans_need_reconnect = 1;
2331         spin_unlock(&ses->chan_lock);
2332
2333         mutex_lock(&ses->session_mutex);
2334         rc = cifs_negotiate_protocol(xid, ses, server);
2335         if (!rc)
2336                 rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
2337         mutex_unlock(&ses->session_mutex);
2338
2339         /* each channel uses a different signing key */
2340         spin_lock(&ses->chan_lock);
2341         memcpy(ses->chans[0].signkey, ses->smb3signingkey,
2342                sizeof(ses->smb3signingkey));
2343         spin_unlock(&ses->chan_lock);
2344
2345         if (rc)
2346                 goto get_ses_fail;
2347
2348         /*
2349          * success, put it on the list and add it as first channel
2350          * note: the session becomes active soon after this. So you'll
2351          * need to lock before changing something in the session.
2352          */
2353         spin_lock(&cifs_tcp_ses_lock);
2354         ses->dfs_root_ses = ctx->dfs_root_ses;
2355         if (ses->dfs_root_ses)
2356                 ses->dfs_root_ses->ses_count++;
2357         list_add(&ses->smb_ses_list, &server->smb_ses_list);
2358         spin_unlock(&cifs_tcp_ses_lock);
2359
2360         cifs_setup_ipc(ses, ctx);
2361
2362         free_xid(xid);
2363
2364         return ses;
2365
2366 get_ses_fail:
2367         sesInfoFree(ses);
2368         free_xid(xid);
2369         return ERR_PTR(rc);
2370 }
2371
2372 /* this function must be called with tc_lock held */
2373 static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
2374 {
2375         struct TCP_Server_Info *server = tcon->ses->server;
2376
2377         if (tcon->status == TID_EXITING)
2378                 return 0;
2379
2380         if (tcon->origin_fullpath) {
2381                 if (!ctx->source ||
2382                     !dfs_src_pathname_equal(ctx->source,
2383                                             tcon->origin_fullpath))
2384                         return 0;
2385         } else if (!server->leaf_fullpath &&
2386                    strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE)) {
2387                 return 0;
2388         }
2389         if (tcon->seal != ctx->seal)
2390                 return 0;
2391         if (tcon->snapshot_time != ctx->snapshot_time)
2392                 return 0;
2393         if (tcon->handle_timeout != ctx->handle_timeout)
2394                 return 0;
2395         if (tcon->no_lease != ctx->no_lease)
2396                 return 0;
2397         if (tcon->nodelete != ctx->nodelete)
2398                 return 0;
2399         return 1;
2400 }
2401
2402 static struct cifs_tcon *
2403 cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2404 {
2405         struct cifs_tcon *tcon;
2406
2407         spin_lock(&cifs_tcp_ses_lock);
2408         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
2409                 spin_lock(&tcon->tc_lock);
2410                 if (!match_tcon(tcon, ctx)) {
2411                         spin_unlock(&tcon->tc_lock);
2412                         continue;
2413                 }
2414                 ++tcon->tc_count;
2415                 spin_unlock(&tcon->tc_lock);
2416                 spin_unlock(&cifs_tcp_ses_lock);
2417                 return tcon;
2418         }
2419         spin_unlock(&cifs_tcp_ses_lock);
2420         return NULL;
2421 }
2422
2423 void
2424 cifs_put_tcon(struct cifs_tcon *tcon)
2425 {
2426         unsigned int xid;
2427         struct cifs_ses *ses;
2428
2429         /*
2430          * IPC tcon share the lifetime of their session and are
2431          * destroyed in the session put function
2432          */
2433         if (tcon == NULL || tcon->ipc)
2434                 return;
2435
2436         ses = tcon->ses;
2437         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2438         spin_lock(&cifs_tcp_ses_lock);
2439         spin_lock(&tcon->tc_lock);
2440         if (--tcon->tc_count > 0) {
2441                 spin_unlock(&tcon->tc_lock);
2442                 spin_unlock(&cifs_tcp_ses_lock);
2443                 return;
2444         }
2445
2446         /* tc_count can never go negative */
2447         WARN_ON(tcon->tc_count < 0);
2448
2449         list_del_init(&tcon->tcon_list);
2450         tcon->status = TID_EXITING;
2451         spin_unlock(&tcon->tc_lock);
2452         spin_unlock(&cifs_tcp_ses_lock);
2453
2454         /* cancel polling of interfaces */
2455         cancel_delayed_work_sync(&tcon->query_interfaces);
2456 #ifdef CONFIG_CIFS_DFS_UPCALL
2457         cancel_delayed_work_sync(&tcon->dfs_cache_work);
2458 #endif
2459
2460         if (tcon->use_witness) {
2461                 int rc;
2462
2463                 rc = cifs_swn_unregister(tcon);
2464                 if (rc < 0) {
2465                         cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2466                                         __func__, rc);
2467                 }
2468         }
2469
2470         xid = get_xid();
2471         if (ses->server->ops->tree_disconnect)
2472                 ses->server->ops->tree_disconnect(xid, tcon);
2473         _free_xid(xid);
2474
2475         cifs_fscache_release_super_cookie(tcon);
2476         tconInfoFree(tcon);
2477         cifs_put_smb_ses(ses);
2478 }
2479
2480 /**
2481  * cifs_get_tcon - get a tcon matching @ctx data from @ses
2482  * @ses: smb session to issue the request on
2483  * @ctx: the superblock configuration context to use for building the
2484  *
2485  * - tcon refcount is the number of mount points using the tcon.
2486  * - ses refcount is the number of tcon using the session.
2487  *
2488  * 1. This function assumes it is being called from cifs_mount() where
2489  *    we already got a session reference (ses refcount +1).
2490  *
2491  * 2. Since we're in the context of adding a mount point, the end
2492  *    result should be either:
2493  *
2494  * a) a new tcon already allocated with refcount=1 (1 mount point) and
2495  *    its session refcount incremented (1 new tcon). This +1 was
2496  *    already done in (1).
2497  *
2498  * b) an existing tcon with refcount+1 (add a mount point to it) and
2499  *    identical ses refcount (no new tcon). Because of (1) we need to
2500  *    decrement the ses refcount.
2501  */
2502 static struct cifs_tcon *
2503 cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2504 {
2505         struct cifs_tcon *tcon;
2506         bool nohandlecache;
2507         int rc, xid;
2508
2509         tcon = cifs_find_tcon(ses, ctx);
2510         if (tcon) {
2511                 /*
2512                  * tcon has refcount already incremented but we need to
2513                  * decrement extra ses reference gotten by caller (case b)
2514                  */
2515                 cifs_dbg(FYI, "Found match on UNC path\n");
2516                 cifs_put_smb_ses(ses);
2517                 return tcon;
2518         }
2519
2520         if (!ses->server->ops->tree_connect) {
2521                 rc = -ENOSYS;
2522                 goto out_fail;
2523         }
2524
2525         if (ses->server->dialect >= SMB20_PROT_ID &&
2526             (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING))
2527                 nohandlecache = ctx->nohandlecache;
2528         else
2529                 nohandlecache = true;
2530         tcon = tcon_info_alloc(!nohandlecache);
2531         if (tcon == NULL) {
2532                 rc = -ENOMEM;
2533                 goto out_fail;
2534         }
2535         tcon->nohandlecache = nohandlecache;
2536
2537         if (ctx->snapshot_time) {
2538                 if (ses->server->vals->protocol_id == 0) {
2539                         cifs_dbg(VFS,
2540                              "Use SMB2 or later for snapshot mount option\n");
2541                         rc = -EOPNOTSUPP;
2542                         goto out_fail;
2543                 } else
2544                         tcon->snapshot_time = ctx->snapshot_time;
2545         }
2546
2547         if (ctx->handle_timeout) {
2548                 if (ses->server->vals->protocol_id == 0) {
2549                         cifs_dbg(VFS,
2550                              "Use SMB2.1 or later for handle timeout option\n");
2551                         rc = -EOPNOTSUPP;
2552                         goto out_fail;
2553                 } else
2554                         tcon->handle_timeout = ctx->handle_timeout;
2555         }
2556
2557         tcon->ses = ses;
2558         if (ctx->password) {
2559                 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2560                 if (!tcon->password) {
2561                         rc = -ENOMEM;
2562                         goto out_fail;
2563                 }
2564         }
2565
2566         if (ctx->seal) {
2567                 if (ses->server->vals->protocol_id == 0) {
2568                         cifs_dbg(VFS,
2569                                  "SMB3 or later required for encryption\n");
2570                         rc = -EOPNOTSUPP;
2571                         goto out_fail;
2572                 } else if (tcon->ses->server->capabilities &
2573                                         SMB2_GLOBAL_CAP_ENCRYPTION)
2574                         tcon->seal = true;
2575                 else {
2576                         cifs_dbg(VFS, "Encryption is not supported on share\n");
2577                         rc = -EOPNOTSUPP;
2578                         goto out_fail;
2579                 }
2580         }
2581
2582         if (ctx->linux_ext) {
2583                 if (ses->server->posix_ext_supported) {
2584                         tcon->posix_extensions = true;
2585                         pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2586                 } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
2587                     (strcmp(ses->server->vals->version_string,
2588                      SMB3ANY_VERSION_STRING) == 0) ||
2589                     (strcmp(ses->server->vals->version_string,
2590                      SMBDEFAULT_VERSION_STRING) == 0)) {
2591                         cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2592                         rc = -EOPNOTSUPP;
2593                         goto out_fail;
2594                 } else {
2595                         cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
2596                                 "disabled but required for POSIX extensions\n");
2597                         rc = -EOPNOTSUPP;
2598                         goto out_fail;
2599                 }
2600         }
2601
2602         xid = get_xid();
2603         rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2604                                             ctx->local_nls);
2605         free_xid(xid);
2606         cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2607         if (rc)
2608                 goto out_fail;
2609
2610         tcon->use_persistent = false;
2611         /* check if SMB2 or later, CIFS does not support persistent handles */
2612         if (ctx->persistent) {
2613                 if (ses->server->vals->protocol_id == 0) {
2614                         cifs_dbg(VFS,
2615                              "SMB3 or later required for persistent handles\n");
2616                         rc = -EOPNOTSUPP;
2617                         goto out_fail;
2618                 } else if (ses->server->capabilities &
2619                            SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2620                         tcon->use_persistent = true;
2621                 else /* persistent handles requested but not supported */ {
2622                         cifs_dbg(VFS,
2623                                 "Persistent handles not supported on share\n");
2624                         rc = -EOPNOTSUPP;
2625                         goto out_fail;
2626                 }
2627         } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2628              && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2629              && (ctx->nopersistent == false)) {
2630                 cifs_dbg(FYI, "enabling persistent handles\n");
2631                 tcon->use_persistent = true;
2632         } else if (ctx->resilient) {
2633                 if (ses->server->vals->protocol_id == 0) {
2634                         cifs_dbg(VFS,
2635                              "SMB2.1 or later required for resilient handles\n");
2636                         rc = -EOPNOTSUPP;
2637                         goto out_fail;
2638                 }
2639                 tcon->use_resilient = true;
2640         }
2641
2642         tcon->use_witness = false;
2643         if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2644                 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2645                         if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2646                                 /*
2647                                  * Set witness in use flag in first place
2648                                  * to retry registration in the echo task
2649                                  */
2650                                 tcon->use_witness = true;
2651                                 /* And try to register immediately */
2652                                 rc = cifs_swn_register(tcon);
2653                                 if (rc < 0) {
2654                                         cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2655                                         goto out_fail;
2656                                 }
2657                         } else {
2658                                 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2659                                 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2660                                 rc = -EOPNOTSUPP;
2661                                 goto out_fail;
2662                         }
2663                 } else {
2664                         cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2665                         rc = -EOPNOTSUPP;
2666                         goto out_fail;
2667                 }
2668         }
2669
2670         /* If the user really knows what they are doing they can override */
2671         if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2672                 if (ctx->cache_ro)
2673                         cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2674                 else if (ctx->cache_rw)
2675                         cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2676         }
2677
2678         if (ctx->no_lease) {
2679                 if (ses->server->vals->protocol_id == 0) {
2680                         cifs_dbg(VFS,
2681                                 "SMB2 or later required for nolease option\n");
2682                         rc = -EOPNOTSUPP;
2683                         goto out_fail;
2684                 } else
2685                         tcon->no_lease = ctx->no_lease;
2686         }
2687
2688         /*
2689          * We can have only one retry value for a connection to a share so for
2690          * resources mounted more than once to the same server share the last
2691          * value passed in for the retry flag is used.
2692          */
2693         tcon->retry = ctx->retry;
2694         tcon->nocase = ctx->nocase;
2695         tcon->broken_sparse_sup = ctx->no_sparse;
2696         tcon->max_cached_dirs = ctx->max_cached_dirs;
2697         tcon->nodelete = ctx->nodelete;
2698         tcon->local_lease = ctx->local_lease;
2699         INIT_LIST_HEAD(&tcon->pending_opens);
2700         tcon->status = TID_GOOD;
2701
2702         INIT_DELAYED_WORK(&tcon->query_interfaces,
2703                           smb2_query_server_interfaces);
2704         if (ses->server->dialect >= SMB30_PROT_ID &&
2705             (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
2706                 /* schedule query interfaces poll */
2707                 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
2708                                    (SMB_INTERFACE_POLL_INTERVAL * HZ));
2709         }
2710 #ifdef CONFIG_CIFS_DFS_UPCALL
2711         INIT_DELAYED_WORK(&tcon->dfs_cache_work, dfs_cache_refresh);
2712 #endif
2713         spin_lock(&cifs_tcp_ses_lock);
2714         list_add(&tcon->tcon_list, &ses->tcon_list);
2715         spin_unlock(&cifs_tcp_ses_lock);
2716
2717         return tcon;
2718
2719 out_fail:
2720         tconInfoFree(tcon);
2721         return ERR_PTR(rc);
2722 }
2723
2724 void
2725 cifs_put_tlink(struct tcon_link *tlink)
2726 {
2727         if (!tlink || IS_ERR(tlink))
2728                 return;
2729
2730         if (!atomic_dec_and_test(&tlink->tl_count) ||
2731             test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2732                 tlink->tl_time = jiffies;
2733                 return;
2734         }
2735
2736         if (!IS_ERR(tlink_tcon(tlink)))
2737                 cifs_put_tcon(tlink_tcon(tlink));
2738         kfree(tlink);
2739         return;
2740 }
2741
2742 static int
2743 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2744 {
2745         struct cifs_sb_info *old = CIFS_SB(sb);
2746         struct cifs_sb_info *new = mnt_data->cifs_sb;
2747         unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2748         unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2749
2750         if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2751                 return 0;
2752
2753         if (old->mnt_cifs_serverino_autodisabled)
2754                 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2755
2756         if (oldflags != newflags)
2757                 return 0;
2758
2759         /*
2760          * We want to share sb only if we don't specify an r/wsize or
2761          * specified r/wsize is greater than or equal to existing one.
2762          */
2763         if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2764                 return 0;
2765
2766         if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2767                 return 0;
2768
2769         if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2770             !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2771                 return 0;
2772
2773         if (old->ctx->file_mode != new->ctx->file_mode ||
2774             old->ctx->dir_mode != new->ctx->dir_mode)
2775                 return 0;
2776
2777         if (strcmp(old->local_nls->charset, new->local_nls->charset))
2778                 return 0;
2779
2780         if (old->ctx->acregmax != new->ctx->acregmax)
2781                 return 0;
2782         if (old->ctx->acdirmax != new->ctx->acdirmax)
2783                 return 0;
2784         if (old->ctx->closetimeo != new->ctx->closetimeo)
2785                 return 0;
2786
2787         return 1;
2788 }
2789
2790 static int match_prepath(struct super_block *sb,
2791                          struct cifs_tcon *tcon,
2792                          struct cifs_mnt_data *mnt_data)
2793 {
2794         struct smb3_fs_context *ctx = mnt_data->ctx;
2795         struct cifs_sb_info *old = CIFS_SB(sb);
2796         struct cifs_sb_info *new = mnt_data->cifs_sb;
2797         bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2798                 old->prepath;
2799         bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2800                 new->prepath;
2801
2802         if (tcon->origin_fullpath &&
2803             dfs_src_pathname_equal(tcon->origin_fullpath, ctx->source))
2804                 return 1;
2805
2806         if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2807                 return 1;
2808         else if (!old_set && !new_set)
2809                 return 1;
2810
2811         return 0;
2812 }
2813
2814 int
2815 cifs_match_super(struct super_block *sb, void *data)
2816 {
2817         struct cifs_mnt_data *mnt_data = data;
2818         struct smb3_fs_context *ctx;
2819         struct cifs_sb_info *cifs_sb;
2820         struct TCP_Server_Info *tcp_srv;
2821         struct cifs_ses *ses;
2822         struct cifs_tcon *tcon;
2823         struct tcon_link *tlink;
2824         int rc = 0;
2825
2826         spin_lock(&cifs_tcp_ses_lock);
2827         cifs_sb = CIFS_SB(sb);
2828
2829         /* We do not want to use a superblock that has been shutdown */
2830         if (CIFS_MOUNT_SHUTDOWN & cifs_sb->mnt_cifs_flags) {
2831                 spin_unlock(&cifs_tcp_ses_lock);
2832                 return 0;
2833         }
2834
2835         tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2836         if (IS_ERR_OR_NULL(tlink)) {
2837                 pr_warn_once("%s: skip super matching due to bad tlink(%p)\n",
2838                              __func__, tlink);
2839                 spin_unlock(&cifs_tcp_ses_lock);
2840                 return 0;
2841         }
2842         tcon = tlink_tcon(tlink);
2843         ses = tcon->ses;
2844         tcp_srv = ses->server;
2845
2846         ctx = mnt_data->ctx;
2847
2848         spin_lock(&tcp_srv->srv_lock);
2849         spin_lock(&ses->ses_lock);
2850         spin_lock(&ses->chan_lock);
2851         spin_lock(&tcon->tc_lock);
2852         if (!match_server(tcp_srv, ctx, true) ||
2853             !match_session(ses, ctx) ||
2854             !match_tcon(tcon, ctx) ||
2855             !match_prepath(sb, tcon, mnt_data)) {
2856                 rc = 0;
2857                 goto out;
2858         }
2859
2860         rc = compare_mount_options(sb, mnt_data);
2861 out:
2862         spin_unlock(&tcon->tc_lock);
2863         spin_unlock(&ses->chan_lock);
2864         spin_unlock(&ses->ses_lock);
2865         spin_unlock(&tcp_srv->srv_lock);
2866
2867         spin_unlock(&cifs_tcp_ses_lock);
2868         cifs_put_tlink(tlink);
2869         return rc;
2870 }
2871
2872 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2873 static struct lock_class_key cifs_key[2];
2874 static struct lock_class_key cifs_slock_key[2];
2875
2876 static inline void
2877 cifs_reclassify_socket4(struct socket *sock)
2878 {
2879         struct sock *sk = sock->sk;
2880         BUG_ON(!sock_allow_reclassification(sk));
2881         sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2882                 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2883 }
2884
2885 static inline void
2886 cifs_reclassify_socket6(struct socket *sock)
2887 {
2888         struct sock *sk = sock->sk;
2889         BUG_ON(!sock_allow_reclassification(sk));
2890         sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2891                 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2892 }
2893 #else
2894 static inline void
2895 cifs_reclassify_socket4(struct socket *sock)
2896 {
2897 }
2898
2899 static inline void
2900 cifs_reclassify_socket6(struct socket *sock)
2901 {
2902 }
2903 #endif
2904
2905 /* See RFC1001 section 14 on representation of Netbios names */
2906 static void rfc1002mangle(char *target, char *source, unsigned int length)
2907 {
2908         unsigned int i, j;
2909
2910         for (i = 0, j = 0; i < (length); i++) {
2911                 /* mask a nibble at a time and encode */
2912                 target[j] = 'A' + (0x0F & (source[i] >> 4));
2913                 target[j+1] = 'A' + (0x0F & source[i]);
2914                 j += 2;
2915         }
2916
2917 }
2918
2919 static int
2920 bind_socket(struct TCP_Server_Info *server)
2921 {
2922         int rc = 0;
2923         if (server->srcaddr.ss_family != AF_UNSPEC) {
2924                 /* Bind to the specified local IP address */
2925                 struct socket *socket = server->ssocket;
2926                 rc = kernel_bind(socket,
2927                                  (struct sockaddr *) &server->srcaddr,
2928                                  sizeof(server->srcaddr));
2929                 if (rc < 0) {
2930                         struct sockaddr_in *saddr4;
2931                         struct sockaddr_in6 *saddr6;
2932                         saddr4 = (struct sockaddr_in *)&server->srcaddr;
2933                         saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2934                         if (saddr6->sin6_family == AF_INET6)
2935                                 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2936                                          &saddr6->sin6_addr, rc);
2937                         else
2938                                 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2939                                          &saddr4->sin_addr.s_addr, rc);
2940                 }
2941         }
2942         return rc;
2943 }
2944
2945 static int
2946 ip_rfc1001_connect(struct TCP_Server_Info *server)
2947 {
2948         int rc = 0;
2949         /*
2950          * some servers require RFC1001 sessinit before sending
2951          * negprot - BB check reconnection in case where second
2952          * sessinit is sent but no second negprot
2953          */
2954         struct rfc1002_session_packet req = {};
2955         struct smb_hdr *smb_buf = (struct smb_hdr *)&req;
2956         unsigned int len;
2957
2958         req.trailer.session_req.called_len = sizeof(req.trailer.session_req.called_name);
2959
2960         if (server->server_RFC1001_name[0] != 0)
2961                 rfc1002mangle(req.trailer.session_req.called_name,
2962                               server->server_RFC1001_name,
2963                               RFC1001_NAME_LEN_WITH_NULL);
2964         else
2965                 rfc1002mangle(req.trailer.session_req.called_name,
2966                               DEFAULT_CIFS_CALLED_NAME,
2967                               RFC1001_NAME_LEN_WITH_NULL);
2968
2969         req.trailer.session_req.calling_len = sizeof(req.trailer.session_req.calling_name);
2970
2971         /* calling name ends in null (byte 16) from old smb convention */
2972         if (server->workstation_RFC1001_name[0] != 0)
2973                 rfc1002mangle(req.trailer.session_req.calling_name,
2974                               server->workstation_RFC1001_name,
2975                               RFC1001_NAME_LEN_WITH_NULL);
2976         else
2977                 rfc1002mangle(req.trailer.session_req.calling_name,
2978                               "LINUX_CIFS_CLNT",
2979                               RFC1001_NAME_LEN_WITH_NULL);
2980
2981         /*
2982          * As per rfc1002, @len must be the number of bytes that follows the
2983          * length field of a rfc1002 session request payload.
2984          */
2985         len = sizeof(req) - offsetof(struct rfc1002_session_packet, trailer.session_req);
2986
2987         smb_buf->smb_buf_length = cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | len);
2988         rc = smb_send(server, smb_buf, len);
2989         /*
2990          * RFC1001 layer in at least one server requires very short break before
2991          * negprot presumably because not expecting negprot to follow so fast.
2992          * This is a simple solution that works without complicating the code
2993          * and causes no significant slowing down on mount for everyone else
2994          */
2995         usleep_range(1000, 2000);
2996
2997         return rc;
2998 }
2999
3000 static int
3001 generic_ip_connect(struct TCP_Server_Info *server)
3002 {
3003         struct sockaddr *saddr;
3004         struct socket *socket;
3005         int slen, sfamily;
3006         __be16 sport;
3007         int rc = 0;
3008
3009         saddr = (struct sockaddr *) &server->dstaddr;
3010
3011         if (server->dstaddr.ss_family == AF_INET6) {
3012                 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
3013
3014                 sport = ipv6->sin6_port;
3015                 slen = sizeof(struct sockaddr_in6);
3016                 sfamily = AF_INET6;
3017                 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
3018                                 ntohs(sport));
3019         } else {
3020                 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
3021
3022                 sport = ipv4->sin_port;
3023                 slen = sizeof(struct sockaddr_in);
3024                 sfamily = AF_INET;
3025                 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
3026                                 ntohs(sport));
3027         }
3028
3029         if (server->ssocket) {
3030                 socket = server->ssocket;
3031         } else {
3032                 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
3033                                    IPPROTO_TCP, &server->ssocket, 1);
3034                 if (rc < 0) {
3035                         cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
3036                         return rc;
3037                 }
3038
3039                 /* BB other socket options to set KEEPALIVE, NODELAY? */
3040                 cifs_dbg(FYI, "Socket created\n");
3041                 socket = server->ssocket;
3042                 socket->sk->sk_allocation = GFP_NOFS;
3043                 socket->sk->sk_use_task_frag = false;
3044                 if (sfamily == AF_INET6)
3045                         cifs_reclassify_socket6(socket);
3046                 else
3047                         cifs_reclassify_socket4(socket);
3048         }
3049
3050         rc = bind_socket(server);
3051         if (rc < 0)
3052                 return rc;
3053
3054         /*
3055          * Eventually check for other socket options to change from
3056          * the default. sock_setsockopt not used because it expects
3057          * user space buffer
3058          */
3059         socket->sk->sk_rcvtimeo = 7 * HZ;
3060         socket->sk->sk_sndtimeo = 5 * HZ;
3061
3062         /* make the bufsizes depend on wsize/rsize and max requests */
3063         if (server->noautotune) {
3064                 if (socket->sk->sk_sndbuf < (200 * 1024))
3065                         socket->sk->sk_sndbuf = 200 * 1024;
3066                 if (socket->sk->sk_rcvbuf < (140 * 1024))
3067                         socket->sk->sk_rcvbuf = 140 * 1024;
3068         }
3069
3070         if (server->tcp_nodelay)
3071                 tcp_sock_set_nodelay(socket->sk);
3072
3073         cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
3074                  socket->sk->sk_sndbuf,
3075                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
3076
3077         rc = kernel_connect(socket, saddr, slen,
3078                             server->noblockcnt ? O_NONBLOCK : 0);
3079         /*
3080          * When mounting SMB root file systems, we do not want to block in
3081          * connect. Otherwise bail out and then let cifs_reconnect() perform
3082          * reconnect failover - if possible.
3083          */
3084         if (server->noblockcnt && rc == -EINPROGRESS)
3085                 rc = 0;
3086         if (rc < 0) {
3087                 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3088                 trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
3089                 sock_release(socket);
3090                 server->ssocket = NULL;
3091                 return rc;
3092         }
3093         trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
3094         if (sport == htons(RFC1001_PORT))
3095                 rc = ip_rfc1001_connect(server);
3096
3097         return rc;
3098 }
3099
3100 static int
3101 ip_connect(struct TCP_Server_Info *server)
3102 {
3103         __be16 *sport;
3104         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3105         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3106
3107         if (server->dstaddr.ss_family == AF_INET6)
3108                 sport = &addr6->sin6_port;
3109         else
3110                 sport = &addr->sin_port;
3111
3112         if (*sport == 0) {
3113                 int rc;
3114
3115                 /* try with 445 port at first */
3116                 *sport = htons(CIFS_PORT);
3117
3118                 rc = generic_ip_connect(server);
3119                 if (rc >= 0)
3120                         return rc;
3121
3122                 /* if it failed, try with 139 port */
3123                 *sport = htons(RFC1001_PORT);
3124         }
3125
3126         return generic_ip_connect(server);
3127 }
3128
3129 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3130 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3131                           struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3132 {
3133         /*
3134          * If we are reconnecting then should we check to see if
3135          * any requested capabilities changed locally e.g. via
3136          * remount but we can not do much about it here
3137          * if they have (even if we could detect it by the following)
3138          * Perhaps we could add a backpointer to array of sb from tcon
3139          * or if we change to make all sb to same share the same
3140          * sb as NFS - then we only have one backpointer to sb.
3141          * What if we wanted to mount the server share twice once with
3142          * and once without posixacls or posix paths?
3143          */
3144         __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3145
3146         if (ctx && ctx->no_linux_ext) {
3147                 tcon->fsUnixInfo.Capability = 0;
3148                 tcon->unix_ext = 0; /* Unix Extensions disabled */
3149                 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
3150                 return;
3151         } else if (ctx)
3152                 tcon->unix_ext = 1; /* Unix Extensions supported */
3153
3154         if (!tcon->unix_ext) {
3155                 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
3156                 return;
3157         }
3158
3159         if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
3160                 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3161                 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
3162                 /*
3163                  * check for reconnect case in which we do not
3164                  * want to change the mount behavior if we can avoid it
3165                  */
3166                 if (ctx == NULL) {
3167                         /*
3168                          * turn off POSIX ACL and PATHNAMES if not set
3169                          * originally at mount time
3170                          */
3171                         if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
3172                                 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3173                         if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3174                                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3175                                         cifs_dbg(VFS, "POSIXPATH support change\n");
3176                                 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3177                         } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3178                                 cifs_dbg(VFS, "possible reconnect error\n");
3179                                 cifs_dbg(VFS, "server disabled POSIX path support\n");
3180                         }
3181                 }
3182
3183                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3184                         cifs_dbg(VFS, "per-share encryption not supported yet\n");
3185
3186                 cap &= CIFS_UNIX_CAP_MASK;
3187                 if (ctx && ctx->no_psx_acl)
3188                         cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3189                 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
3190                         cifs_dbg(FYI, "negotiated posix acl support\n");
3191                         if (cifs_sb)
3192                                 cifs_sb->mnt_cifs_flags |=
3193                                         CIFS_MOUNT_POSIXACL;
3194                 }
3195
3196                 if (ctx && ctx->posix_paths == 0)
3197                         cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3198                 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
3199                         cifs_dbg(FYI, "negotiate posix pathnames\n");
3200                         if (cifs_sb)
3201                                 cifs_sb->mnt_cifs_flags |=
3202                                         CIFS_MOUNT_POSIX_PATHS;
3203                 }
3204
3205                 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
3206 #ifdef CONFIG_CIFS_DEBUG2
3207                 if (cap & CIFS_UNIX_FCNTL_CAP)
3208                         cifs_dbg(FYI, "FCNTL cap\n");
3209                 if (cap & CIFS_UNIX_EXTATTR_CAP)
3210                         cifs_dbg(FYI, "EXTATTR cap\n");
3211                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3212                         cifs_dbg(FYI, "POSIX path cap\n");
3213                 if (cap & CIFS_UNIX_XATTR_CAP)
3214                         cifs_dbg(FYI, "XATTR cap\n");
3215                 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
3216                         cifs_dbg(FYI, "POSIX ACL cap\n");
3217                 if (cap & CIFS_UNIX_LARGE_READ_CAP)
3218                         cifs_dbg(FYI, "very large read cap\n");
3219                 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
3220                         cifs_dbg(FYI, "very large write cap\n");
3221                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
3222                         cifs_dbg(FYI, "transport encryption cap\n");
3223                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3224                         cifs_dbg(FYI, "mandatory transport encryption cap\n");
3225 #endif /* CIFS_DEBUG2 */
3226                 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
3227                         if (ctx == NULL)
3228                                 cifs_dbg(FYI, "resetting capabilities failed\n");
3229                         else
3230                                 cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
3231
3232                 }
3233         }
3234 }
3235 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3236
3237 int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
3238 {
3239         struct smb3_fs_context *ctx = cifs_sb->ctx;
3240
3241         INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
3242
3243         spin_lock_init(&cifs_sb->tlink_tree_lock);
3244         cifs_sb->tlink_tree = RB_ROOT;
3245
3246         cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
3247                  ctx->file_mode, ctx->dir_mode);
3248
3249         /* this is needed for ASCII cp to Unicode converts */
3250         if (ctx->iocharset == NULL) {
3251                 /* load_nls_default cannot return null */
3252                 cifs_sb->local_nls = load_nls_default();
3253         } else {
3254                 cifs_sb->local_nls = load_nls(ctx->iocharset);
3255                 if (cifs_sb->local_nls == NULL) {
3256                         cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
3257                                  ctx->iocharset);
3258                         return -ELIBACC;
3259                 }
3260         }
3261         ctx->local_nls = cifs_sb->local_nls;
3262
3263         smb3_update_mnt_flags(cifs_sb);
3264
3265         if (ctx->direct_io)
3266                 cifs_dbg(FYI, "mounting share using direct i/o\n");
3267         if (ctx->cache_ro) {
3268                 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
3269                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
3270         } else if (ctx->cache_rw) {
3271                 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
3272                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
3273                                             CIFS_MOUNT_RW_CACHE);
3274         }
3275
3276         if ((ctx->cifs_acl) && (ctx->dynperm))
3277                 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
3278
3279         if (ctx->prepath) {
3280                 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
3281                 if (cifs_sb->prepath == NULL)
3282                         return -ENOMEM;
3283                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3284         }
3285
3286         return 0;
3287 }
3288
3289 /* Release all succeed connections */
3290 void cifs_mount_put_conns(struct cifs_mount_ctx *mnt_ctx)
3291 {
3292         int rc = 0;
3293
3294         if (mnt_ctx->tcon)
3295                 cifs_put_tcon(mnt_ctx->tcon);
3296         else if (mnt_ctx->ses)
3297                 cifs_put_smb_ses(mnt_ctx->ses);
3298         else if (mnt_ctx->server)
3299                 cifs_put_tcp_session(mnt_ctx->server, 0);
3300         mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
3301         free_xid(mnt_ctx->xid);
3302 }
3303
3304 int cifs_mount_get_session(struct cifs_mount_ctx *mnt_ctx)
3305 {
3306         struct TCP_Server_Info *server = NULL;
3307         struct smb3_fs_context *ctx;
3308         struct cifs_ses *ses = NULL;
3309         unsigned int xid;
3310         int rc = 0;
3311
3312         xid = get_xid();
3313
3314         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->fs_ctx)) {
3315                 rc = -EINVAL;
3316                 goto out;
3317         }
3318         ctx = mnt_ctx->fs_ctx;
3319
3320         /* get a reference to a tcp session */
3321         server = cifs_get_tcp_session(ctx, NULL);
3322         if (IS_ERR(server)) {
3323                 rc = PTR_ERR(server);
3324                 server = NULL;
3325                 goto out;
3326         }
3327
3328         /* get a reference to a SMB session */
3329         ses = cifs_get_smb_ses(server, ctx);
3330         if (IS_ERR(ses)) {
3331                 rc = PTR_ERR(ses);
3332                 ses = NULL;
3333                 goto out;
3334         }
3335
3336         if ((ctx->persistent == true) && (!(ses->server->capabilities &
3337                                             SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
3338                 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
3339                 rc = -EOPNOTSUPP;
3340         }
3341
3342 out:
3343         mnt_ctx->xid = xid;
3344         mnt_ctx->server = server;
3345         mnt_ctx->ses = ses;
3346         mnt_ctx->tcon = NULL;
3347
3348         return rc;
3349 }
3350
3351 int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx)
3352 {
3353         struct TCP_Server_Info *server;
3354         struct cifs_sb_info *cifs_sb;
3355         struct smb3_fs_context *ctx;
3356         struct cifs_tcon *tcon = NULL;
3357         int rc = 0;
3358
3359         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->server || !mnt_ctx->ses || !mnt_ctx->fs_ctx ||
3360                          !mnt_ctx->cifs_sb)) {
3361                 rc = -EINVAL;
3362                 goto out;
3363         }
3364         server = mnt_ctx->server;
3365         ctx = mnt_ctx->fs_ctx;
3366         cifs_sb = mnt_ctx->cifs_sb;
3367
3368         /* search for existing tcon to this server share */
3369         tcon = cifs_get_tcon(mnt_ctx->ses, ctx);
3370         if (IS_ERR(tcon)) {
3371                 rc = PTR_ERR(tcon);
3372                 tcon = NULL;
3373                 goto out;
3374         }
3375
3376         /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
3377         if (tcon->posix_extensions)
3378                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
3379
3380 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3381         /* tell server which Unix caps we support */
3382         if (cap_unix(tcon->ses)) {
3383                 /*
3384                  * reset of caps checks mount to see if unix extensions disabled
3385                  * for just this mount.
3386                  */
3387                 reset_cifs_unix_caps(mnt_ctx->xid, tcon, cifs_sb, ctx);
3388                 spin_lock(&tcon->ses->server->srv_lock);
3389                 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
3390                     (le64_to_cpu(tcon->fsUnixInfo.Capability) &
3391                      CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
3392                         spin_unlock(&tcon->ses->server->srv_lock);
3393                         rc = -EACCES;
3394                         goto out;
3395                 }
3396                 spin_unlock(&tcon->ses->server->srv_lock);
3397         } else
3398 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3399                 tcon->unix_ext = 0; /* server does not support them */
3400
3401         /* do not care if a following call succeed - informational */
3402         if (!tcon->pipe && server->ops->qfs_tcon) {
3403                 server->ops->qfs_tcon(mnt_ctx->xid, tcon, cifs_sb);
3404                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
3405                         if (tcon->fsDevInfo.DeviceCharacteristics &
3406                             cpu_to_le32(FILE_READ_ONLY_DEVICE))
3407                                 cifs_dbg(VFS, "mounted to read only share\n");
3408                         else if ((cifs_sb->mnt_cifs_flags &
3409                                   CIFS_MOUNT_RW_CACHE) == 0)
3410                                 cifs_dbg(VFS, "read only mount of RW share\n");
3411                         /* no need to log a RW mount of a typical RW share */
3412                 }
3413         }
3414
3415         /*
3416          * Clamp the rsize/wsize mount arguments if they are too big for the server
3417          * and set the rsize/wsize to the negotiated values if not passed in by
3418          * the user on mount
3419          */
3420         if ((cifs_sb->ctx->wsize == 0) ||
3421             (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
3422                 cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
3423         if ((cifs_sb->ctx->rsize == 0) ||
3424             (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
3425                 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
3426
3427         /*
3428          * The cookie is initialized from volume info returned above.
3429          * Inside cifs_fscache_get_super_cookie it checks
3430          * that we do not get super cookie twice.
3431          */
3432         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
3433                 cifs_fscache_get_super_cookie(tcon);
3434
3435 out:
3436         mnt_ctx->tcon = tcon;
3437         return rc;
3438 }
3439
3440 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
3441                              struct cifs_tcon *tcon)
3442 {
3443         struct tcon_link *tlink;
3444
3445         /* hang the tcon off of the superblock */
3446         tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
3447         if (tlink == NULL)
3448                 return -ENOMEM;
3449
3450         tlink->tl_uid = ses->linux_uid;
3451         tlink->tl_tcon = tcon;
3452         tlink->tl_time = jiffies;
3453         set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
3454         set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3455
3456         cifs_sb->master_tlink = tlink;
3457         spin_lock(&cifs_sb->tlink_tree_lock);
3458         tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
3459         spin_unlock(&cifs_sb->tlink_tree_lock);
3460
3461         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
3462                                 TLINK_IDLE_EXPIRE);
3463         return 0;
3464 }
3465
3466 static int
3467 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3468                                         unsigned int xid,
3469                                         struct cifs_tcon *tcon,
3470                                         struct cifs_sb_info *cifs_sb,
3471                                         char *full_path,
3472                                         int added_treename)
3473 {
3474         int rc;
3475         char *s;
3476         char sep, tmp;
3477         int skip = added_treename ? 1 : 0;
3478
3479         sep = CIFS_DIR_SEP(cifs_sb);
3480         s = full_path;
3481
3482         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3483         while (rc == 0) {
3484                 /* skip separators */
3485                 while (*s == sep)
3486                         s++;
3487                 if (!*s)
3488                         break;
3489                 /* next separator */
3490                 while (*s && *s != sep)
3491                         s++;
3492                 /*
3493                  * if the treename is added, we then have to skip the first
3494                  * part within the separators
3495                  */
3496                 if (skip) {
3497                         skip = 0;
3498                         continue;
3499                 }
3500                 /*
3501                  * temporarily null-terminate the path at the end of
3502                  * the current component
3503                  */
3504                 tmp = *s;
3505                 *s = 0;
3506                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3507                                                      full_path);
3508                 *s = tmp;
3509         }
3510         return rc;
3511 }
3512
3513 /*
3514  * Check if path is remote (i.e. a DFS share).
3515  *
3516  * Return -EREMOTE if it is, otherwise 0 or -errno.
3517  */
3518 int cifs_is_path_remote(struct cifs_mount_ctx *mnt_ctx)
3519 {
3520         int rc;
3521         struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
3522         struct TCP_Server_Info *server = mnt_ctx->server;
3523         unsigned int xid = mnt_ctx->xid;
3524         struct cifs_tcon *tcon = mnt_ctx->tcon;
3525         struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
3526         char *full_path;
3527
3528         if (!server->ops->is_path_accessible)
3529                 return -EOPNOTSUPP;
3530
3531         /*
3532          * cifs_build_path_to_root works only when we have a valid tcon
3533          */
3534         full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3535                                             tcon->Flags & SMB_SHARE_IS_IN_DFS);
3536         if (full_path == NULL)
3537                 return -ENOMEM;
3538
3539         cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3540
3541         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3542                                              full_path);
3543         if (rc != 0 && rc != -EREMOTE)
3544                 goto out;
3545
3546         if (rc != -EREMOTE) {
3547                 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3548                         cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3549                 if (rc != 0) {
3550                         cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3551                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3552                         rc = 0;
3553                 }
3554         }
3555
3556 out:
3557         kfree(full_path);
3558         return rc;
3559 }
3560
3561 #ifdef CONFIG_CIFS_DFS_UPCALL
3562 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3563 {
3564         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3565         bool isdfs;
3566         int rc;
3567
3568         INIT_LIST_HEAD(&mnt_ctx.dfs_ses_list);
3569
3570         rc = dfs_mount_share(&mnt_ctx, &isdfs);
3571         if (rc)
3572                 goto error;
3573         if (!isdfs)
3574                 goto out;
3575
3576         /*
3577          * After reconnecting to a different server, unique ids won't match anymore, so we disable
3578          * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
3579          */
3580         cifs_autodisable_serverino(cifs_sb);
3581         /*
3582          * Force the use of prefix path to support failover on DFS paths that resolve to targets
3583          * that have different prefix paths.
3584          */
3585         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3586         kfree(cifs_sb->prepath);
3587         cifs_sb->prepath = ctx->prepath;
3588         ctx->prepath = NULL;
3589
3590 out:
3591         cifs_try_adding_channels(mnt_ctx.ses);
3592         rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3593         if (rc)
3594                 goto error;
3595
3596         free_xid(mnt_ctx.xid);
3597         return rc;
3598
3599 error:
3600         dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
3601         cifs_mount_put_conns(&mnt_ctx);
3602         return rc;
3603 }
3604 #else
3605 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3606 {
3607         int rc = 0;
3608         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3609
3610         rc = cifs_mount_get_session(&mnt_ctx);
3611         if (rc)
3612                 goto error;
3613
3614         rc = cifs_mount_get_tcon(&mnt_ctx);
3615         if (rc)
3616                 goto error;
3617
3618         rc = cifs_is_path_remote(&mnt_ctx);
3619         if (rc == -EREMOTE)
3620                 rc = -EOPNOTSUPP;
3621         if (rc)
3622                 goto error;
3623
3624         rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3625         if (rc)
3626                 goto error;
3627
3628         free_xid(mnt_ctx.xid);
3629         return rc;
3630
3631 error:
3632         cifs_mount_put_conns(&mnt_ctx);
3633         return rc;
3634 }
3635 #endif
3636
3637 /*
3638  * Issue a TREE_CONNECT request.
3639  */
3640 int
3641 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3642          const char *tree, struct cifs_tcon *tcon,
3643          const struct nls_table *nls_codepage)
3644 {
3645         struct smb_hdr *smb_buffer;
3646         struct smb_hdr *smb_buffer_response;
3647         TCONX_REQ *pSMB;
3648         TCONX_RSP *pSMBr;
3649         unsigned char *bcc_ptr;
3650         int rc = 0;
3651         int length;
3652         __u16 bytes_left, count;
3653
3654         if (ses == NULL)
3655                 return -EIO;
3656
3657         smb_buffer = cifs_buf_get();
3658         if (smb_buffer == NULL)
3659                 return -ENOMEM;
3660
3661         smb_buffer_response = smb_buffer;
3662
3663         header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3664                         NULL /*no tid */ , 4 /*wct */ );
3665
3666         smb_buffer->Mid = get_next_mid(ses->server);
3667         smb_buffer->Uid = ses->Suid;
3668         pSMB = (TCONX_REQ *) smb_buffer;
3669         pSMBr = (TCONX_RSP *) smb_buffer_response;
3670
3671         pSMB->AndXCommand = 0xFF;
3672         pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3673         bcc_ptr = &pSMB->Password[0];
3674
3675         pSMB->PasswordLength = cpu_to_le16(1);  /* minimum */
3676         *bcc_ptr = 0; /* password is null byte */
3677         bcc_ptr++;              /* skip password */
3678         /* already aligned so no need to do it below */
3679
3680         if (ses->server->sign)
3681                 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3682
3683         if (ses->capabilities & CAP_STATUS32) {
3684                 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3685         }
3686         if (ses->capabilities & CAP_DFS) {
3687                 smb_buffer->Flags2 |= SMBFLG2_DFS;
3688         }
3689         if (ses->capabilities & CAP_UNICODE) {
3690                 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3691                 length =
3692                     cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3693                         6 /* max utf8 char length in bytes */ *
3694                         (/* server len*/ + 256 /* share len */), nls_codepage);
3695                 bcc_ptr += 2 * length;  /* convert num 16 bit words to bytes */
3696                 bcc_ptr += 2;   /* skip trailing null */
3697         } else {                /* ASCII */
3698                 strcpy(bcc_ptr, tree);
3699                 bcc_ptr += strlen(tree) + 1;
3700         }
3701         strcpy(bcc_ptr, "?????");
3702         bcc_ptr += strlen("?????");
3703         bcc_ptr += 1;
3704         count = bcc_ptr - &pSMB->Password[0];
3705         be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3706         pSMB->ByteCount = cpu_to_le16(count);
3707
3708         rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3709                          0);
3710
3711         /* above now done in SendReceive */
3712         if (rc == 0) {
3713                 bool is_unicode;
3714
3715                 tcon->tid = smb_buffer_response->Tid;
3716                 bcc_ptr = pByteArea(smb_buffer_response);
3717                 bytes_left = get_bcc(smb_buffer_response);
3718                 length = strnlen(bcc_ptr, bytes_left - 2);
3719                 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3720                         is_unicode = true;
3721                 else
3722                         is_unicode = false;
3723
3724
3725                 /* skip service field (NB: this field is always ASCII) */
3726                 if (length == 3) {
3727                         if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3728                             (bcc_ptr[2] == 'C')) {
3729                                 cifs_dbg(FYI, "IPC connection\n");
3730                                 tcon->ipc = true;
3731                                 tcon->pipe = true;
3732                         }
3733                 } else if (length == 2) {
3734                         if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3735                                 /* the most common case */
3736                                 cifs_dbg(FYI, "disk share connection\n");
3737                         }
3738                 }
3739                 bcc_ptr += length + 1;
3740                 bytes_left -= (length + 1);
3741                 strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
3742
3743                 /* mostly informational -- no need to fail on error here */
3744                 kfree(tcon->nativeFileSystem);
3745                 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3746                                                       bytes_left, is_unicode,
3747                                                       nls_codepage);
3748
3749                 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3750
3751                 if ((smb_buffer_response->WordCount == 3) ||
3752                          (smb_buffer_response->WordCount == 7))
3753                         /* field is in same location */
3754                         tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3755                 else
3756                         tcon->Flags = 0;
3757                 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3758         }
3759
3760         cifs_buf_release(smb_buffer);
3761         return rc;
3762 }
3763
3764 static void delayed_free(struct rcu_head *p)
3765 {
3766         struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3767
3768         unload_nls(cifs_sb->local_nls);
3769         smb3_cleanup_fs_context(cifs_sb->ctx);
3770         kfree(cifs_sb);
3771 }
3772
3773 void
3774 cifs_umount(struct cifs_sb_info *cifs_sb)
3775 {
3776         struct rb_root *root = &cifs_sb->tlink_tree;
3777         struct rb_node *node;
3778         struct tcon_link *tlink;
3779
3780         cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3781
3782         spin_lock(&cifs_sb->tlink_tree_lock);
3783         while ((node = rb_first(root))) {
3784                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3785                 cifs_get_tlink(tlink);
3786                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3787                 rb_erase(node, root);
3788
3789                 spin_unlock(&cifs_sb->tlink_tree_lock);
3790                 cifs_put_tlink(tlink);
3791                 spin_lock(&cifs_sb->tlink_tree_lock);
3792         }
3793         spin_unlock(&cifs_sb->tlink_tree_lock);
3794
3795         kfree(cifs_sb->prepath);
3796         call_rcu(&cifs_sb->rcu, delayed_free);
3797 }
3798
3799 int
3800 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
3801                         struct TCP_Server_Info *server)
3802 {
3803         int rc = 0;
3804
3805         if (!server->ops->need_neg || !server->ops->negotiate)
3806                 return -ENOSYS;
3807
3808         /* only send once per connect */
3809         spin_lock(&server->srv_lock);
3810         if (server->tcpStatus != CifsGood &&
3811             server->tcpStatus != CifsNew &&
3812             server->tcpStatus != CifsNeedNegotiate) {
3813                 spin_unlock(&server->srv_lock);
3814                 return -EHOSTDOWN;
3815         }
3816
3817         if (!server->ops->need_neg(server) &&
3818             server->tcpStatus == CifsGood) {
3819                 spin_unlock(&server->srv_lock);
3820                 return 0;
3821         }
3822
3823         server->tcpStatus = CifsInNegotiate;
3824         spin_unlock(&server->srv_lock);
3825
3826         rc = server->ops->negotiate(xid, ses, server);
3827         if (rc == 0) {
3828                 spin_lock(&server->srv_lock);
3829                 if (server->tcpStatus == CifsInNegotiate)
3830                         server->tcpStatus = CifsGood;
3831                 else
3832                         rc = -EHOSTDOWN;
3833                 spin_unlock(&server->srv_lock);
3834         } else {
3835                 spin_lock(&server->srv_lock);
3836                 if (server->tcpStatus == CifsInNegotiate)
3837                         server->tcpStatus = CifsNeedNegotiate;
3838                 spin_unlock(&server->srv_lock);
3839         }
3840
3841         return rc;
3842 }
3843
3844 int
3845 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3846                    struct TCP_Server_Info *server,
3847                    struct nls_table *nls_info)
3848 {
3849         int rc = -ENOSYS;
3850         struct TCP_Server_Info *pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
3851         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&pserver->dstaddr;
3852         struct sockaddr_in *addr = (struct sockaddr_in *)&pserver->dstaddr;
3853         bool is_binding = false;
3854
3855         spin_lock(&ses->ses_lock);
3856         cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
3857                  __func__, ses->chans_need_reconnect);
3858
3859         if (ses->ses_status != SES_GOOD &&
3860             ses->ses_status != SES_NEW &&
3861             ses->ses_status != SES_NEED_RECON) {
3862                 spin_unlock(&ses->ses_lock);
3863                 return -EHOSTDOWN;
3864         }
3865
3866         /* only send once per connect */
3867         spin_lock(&ses->chan_lock);
3868         if (CIFS_ALL_CHANS_GOOD(ses)) {
3869                 if (ses->ses_status == SES_NEED_RECON)
3870                         ses->ses_status = SES_GOOD;
3871                 spin_unlock(&ses->chan_lock);
3872                 spin_unlock(&ses->ses_lock);
3873                 return 0;
3874         }
3875
3876         cifs_chan_set_in_reconnect(ses, server);
3877         is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
3878         spin_unlock(&ses->chan_lock);
3879
3880         if (!is_binding) {
3881                 ses->ses_status = SES_IN_SETUP;
3882
3883                 /* force iface_list refresh */
3884                 ses->iface_last_update = 0;
3885         }
3886         spin_unlock(&ses->ses_lock);
3887
3888         /* update ses ip_addr only for primary chan */
3889         if (server == pserver) {
3890                 if (server->dstaddr.ss_family == AF_INET6)
3891                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
3892                 else
3893                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
3894         }
3895
3896         if (!is_binding) {
3897                 ses->capabilities = server->capabilities;
3898                 if (!linuxExtEnabled)
3899                         ses->capabilities &= (~server->vals->cap_unix);
3900
3901                 if (ses->auth_key.response) {
3902                         cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3903                                  ses->auth_key.response);
3904                         kfree_sensitive(ses->auth_key.response);
3905                         ses->auth_key.response = NULL;
3906                         ses->auth_key.len = 0;
3907                 }
3908         }
3909
3910         cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3911                  server->sec_mode, server->capabilities, server->timeAdj);
3912
3913         if (server->ops->sess_setup)
3914                 rc = server->ops->sess_setup(xid, ses, server, nls_info);
3915
3916         if (rc) {
3917                 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3918                 spin_lock(&ses->ses_lock);
3919                 if (ses->ses_status == SES_IN_SETUP)
3920                         ses->ses_status = SES_NEED_RECON;
3921                 spin_lock(&ses->chan_lock);
3922                 cifs_chan_clear_in_reconnect(ses, server);
3923                 spin_unlock(&ses->chan_lock);
3924                 spin_unlock(&ses->ses_lock);
3925         } else {
3926                 spin_lock(&ses->ses_lock);
3927                 if (ses->ses_status == SES_IN_SETUP)
3928                         ses->ses_status = SES_GOOD;
3929                 spin_lock(&ses->chan_lock);
3930                 cifs_chan_clear_in_reconnect(ses, server);
3931                 cifs_chan_clear_need_reconnect(ses, server);
3932                 spin_unlock(&ses->chan_lock);
3933                 spin_unlock(&ses->ses_lock);
3934         }
3935
3936         return rc;
3937 }
3938
3939 static int
3940 cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3941 {
3942         ctx->sectype = ses->sectype;
3943
3944         /* krb5 is special, since we don't need username or pw */
3945         if (ctx->sectype == Kerberos)
3946                 return 0;
3947
3948         return cifs_set_cifscreds(ctx, ses);
3949 }
3950
3951 static struct cifs_tcon *
3952 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3953 {
3954         int rc;
3955         struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3956         struct cifs_ses *ses;
3957         struct cifs_tcon *tcon = NULL;
3958         struct smb3_fs_context *ctx;
3959
3960         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3961         if (ctx == NULL)
3962                 return ERR_PTR(-ENOMEM);
3963
3964         ctx->local_nls = cifs_sb->local_nls;
3965         ctx->linux_uid = fsuid;
3966         ctx->cred_uid = fsuid;
3967         ctx->UNC = master_tcon->tree_name;
3968         ctx->retry = master_tcon->retry;
3969         ctx->nocase = master_tcon->nocase;
3970         ctx->nohandlecache = master_tcon->nohandlecache;
3971         ctx->local_lease = master_tcon->local_lease;
3972         ctx->no_lease = master_tcon->no_lease;
3973         ctx->resilient = master_tcon->use_resilient;
3974         ctx->persistent = master_tcon->use_persistent;
3975         ctx->handle_timeout = master_tcon->handle_timeout;
3976         ctx->no_linux_ext = !master_tcon->unix_ext;
3977         ctx->linux_ext = master_tcon->posix_extensions;
3978         ctx->sectype = master_tcon->ses->sectype;
3979         ctx->sign = master_tcon->ses->sign;
3980         ctx->seal = master_tcon->seal;
3981         ctx->witness = master_tcon->use_witness;
3982
3983         rc = cifs_set_vol_auth(ctx, master_tcon->ses);
3984         if (rc) {
3985                 tcon = ERR_PTR(rc);
3986                 goto out;
3987         }
3988
3989         /* get a reference for the same TCP session */
3990         spin_lock(&cifs_tcp_ses_lock);
3991         ++master_tcon->ses->server->srv_count;
3992         spin_unlock(&cifs_tcp_ses_lock);
3993
3994         ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
3995         if (IS_ERR(ses)) {
3996                 tcon = (struct cifs_tcon *)ses;
3997                 cifs_put_tcp_session(master_tcon->ses->server, 0);
3998                 goto out;
3999         }
4000
4001         tcon = cifs_get_tcon(ses, ctx);
4002         if (IS_ERR(tcon)) {
4003                 cifs_put_smb_ses(ses);
4004                 goto out;
4005         }
4006
4007 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
4008         if (cap_unix(ses))
4009                 reset_cifs_unix_caps(0, tcon, NULL, ctx);
4010 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
4011
4012 out:
4013         kfree(ctx->username);
4014         kfree_sensitive(ctx->password);
4015         kfree(ctx);
4016
4017         return tcon;
4018 }
4019
4020 struct cifs_tcon *
4021 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
4022 {
4023         return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
4024 }
4025
4026 /* find and return a tlink with given uid */
4027 static struct tcon_link *
4028 tlink_rb_search(struct rb_root *root, kuid_t uid)
4029 {
4030         struct rb_node *node = root->rb_node;
4031         struct tcon_link *tlink;
4032
4033         while (node) {
4034                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
4035
4036                 if (uid_gt(tlink->tl_uid, uid))
4037                         node = node->rb_left;
4038                 else if (uid_lt(tlink->tl_uid, uid))
4039                         node = node->rb_right;
4040                 else
4041                         return tlink;
4042         }
4043         return NULL;
4044 }
4045
4046 /* insert a tcon_link into the tree */
4047 static void
4048 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
4049 {
4050         struct rb_node **new = &(root->rb_node), *parent = NULL;
4051         struct tcon_link *tlink;
4052
4053         while (*new) {
4054                 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
4055                 parent = *new;
4056
4057                 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
4058                         new = &((*new)->rb_left);
4059                 else
4060                         new = &((*new)->rb_right);
4061         }
4062
4063         rb_link_node(&new_tlink->tl_rbnode, parent, new);
4064         rb_insert_color(&new_tlink->tl_rbnode, root);
4065 }
4066
4067 /*
4068  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4069  * current task.
4070  *
4071  * If the superblock doesn't refer to a multiuser mount, then just return
4072  * the master tcon for the mount.
4073  *
4074  * First, search the rbtree for an existing tcon for this fsuid. If one
4075  * exists, then check to see if it's pending construction. If it is then wait
4076  * for construction to complete. Once it's no longer pending, check to see if
4077  * it failed and either return an error or retry construction, depending on
4078  * the timeout.
4079  *
4080  * If one doesn't exist then insert a new tcon_link struct into the tree and
4081  * try to construct a new one.
4082  */
4083 struct tcon_link *
4084 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4085 {
4086         int ret;
4087         kuid_t fsuid = current_fsuid();
4088         struct tcon_link *tlink, *newtlink;
4089
4090         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4091                 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4092
4093         spin_lock(&cifs_sb->tlink_tree_lock);
4094         tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4095         if (tlink)
4096                 cifs_get_tlink(tlink);
4097         spin_unlock(&cifs_sb->tlink_tree_lock);
4098
4099         if (tlink == NULL) {
4100                 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4101                 if (newtlink == NULL)
4102                         return ERR_PTR(-ENOMEM);
4103                 newtlink->tl_uid = fsuid;
4104                 newtlink->tl_tcon = ERR_PTR(-EACCES);
4105                 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4106                 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4107                 cifs_get_tlink(newtlink);
4108
4109                 spin_lock(&cifs_sb->tlink_tree_lock);
4110                 /* was one inserted after previous search? */
4111                 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4112                 if (tlink) {
4113                         cifs_get_tlink(tlink);
4114                         spin_unlock(&cifs_sb->tlink_tree_lock);
4115                         kfree(newtlink);
4116                         goto wait_for_construction;
4117                 }
4118                 tlink = newtlink;
4119                 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4120                 spin_unlock(&cifs_sb->tlink_tree_lock);
4121         } else {
4122 wait_for_construction:
4123                 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4124                                   TASK_INTERRUPTIBLE);
4125                 if (ret) {
4126                         cifs_put_tlink(tlink);
4127                         return ERR_PTR(-ERESTARTSYS);
4128                 }
4129
4130                 /* if it's good, return it */
4131                 if (!IS_ERR(tlink->tl_tcon))
4132                         return tlink;
4133
4134                 /* return error if we tried this already recently */
4135                 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4136                         cifs_put_tlink(tlink);
4137                         return ERR_PTR(-EACCES);
4138                 }
4139
4140                 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4141                         goto wait_for_construction;
4142         }
4143
4144         tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4145         clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4146         wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4147
4148         if (IS_ERR(tlink->tl_tcon)) {
4149                 cifs_put_tlink(tlink);
4150                 return ERR_PTR(-EACCES);
4151         }
4152
4153         return tlink;
4154 }
4155
4156 /*
4157  * periodic workqueue job that scans tcon_tree for a superblock and closes
4158  * out tcons.
4159  */
4160 static void
4161 cifs_prune_tlinks(struct work_struct *work)
4162 {
4163         struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4164                                                     prune_tlinks.work);
4165         struct rb_root *root = &cifs_sb->tlink_tree;
4166         struct rb_node *node;
4167         struct rb_node *tmp;
4168         struct tcon_link *tlink;
4169
4170         /*
4171          * Because we drop the spinlock in the loop in order to put the tlink
4172          * it's not guarded against removal of links from the tree. The only
4173          * places that remove entries from the tree are this function and
4174          * umounts. Because this function is non-reentrant and is canceled
4175          * before umount can proceed, this is safe.
4176          */
4177         spin_lock(&cifs_sb->tlink_tree_lock);
4178         node = rb_first(root);
4179         while (node != NULL) {
4180                 tmp = node;
4181                 node = rb_next(tmp);
4182                 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4183
4184                 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4185                     atomic_read(&tlink->tl_count) != 0 ||
4186                     time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4187                         continue;
4188
4189                 cifs_get_tlink(tlink);
4190                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4191                 rb_erase(tmp, root);
4192
4193                 spin_unlock(&cifs_sb->tlink_tree_lock);
4194                 cifs_put_tlink(tlink);
4195                 spin_lock(&cifs_sb->tlink_tree_lock);
4196         }
4197         spin_unlock(&cifs_sb->tlink_tree_lock);
4198
4199         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4200                                 TLINK_IDLE_EXPIRE);
4201 }
4202
4203 #ifndef CONFIG_CIFS_DFS_UPCALL
4204 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4205 {
4206         int rc;
4207         const struct smb_version_operations *ops = tcon->ses->server->ops;
4208
4209         /* only send once per connect */
4210         spin_lock(&tcon->tc_lock);
4211         if (tcon->status == TID_GOOD) {
4212                 spin_unlock(&tcon->tc_lock);
4213                 return 0;
4214         }
4215
4216         if (tcon->status != TID_NEW &&
4217             tcon->status != TID_NEED_TCON) {
4218                 spin_unlock(&tcon->tc_lock);
4219                 return -EHOSTDOWN;
4220         }
4221
4222         tcon->status = TID_IN_TCON;
4223         spin_unlock(&tcon->tc_lock);
4224
4225         rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
4226         if (rc) {
4227                 spin_lock(&tcon->tc_lock);
4228                 if (tcon->status == TID_IN_TCON)
4229                         tcon->status = TID_NEED_TCON;
4230                 spin_unlock(&tcon->tc_lock);
4231         } else {
4232                 spin_lock(&tcon->tc_lock);
4233                 if (tcon->status == TID_IN_TCON)
4234                         tcon->status = TID_GOOD;
4235                 tcon->need_reconnect = false;
4236                 spin_unlock(&tcon->tc_lock);
4237         }
4238
4239         return rc;
4240 }
4241 #endif