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 ([email protected])
   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
 406                         /* increase ref count which reconnect work will drop */
 407                         spin_lock(&cifs_tcp_ses_lock);
 408                         server->srv_count++;
 409                         spin_unlock(&cifs_tcp_ses_lock);
 410                         if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))
 411                                 cifs_put_tcp_session(server, false);
 412                 }
 413         } while (server->tcpStatus == CifsNeedReconnect);
 414
 415         spin_lock(&server->srv_lock);
 416         if (server->tcpStatus == CifsNeedNegotiate)
 417                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 418         spin_unlock(&server->srv_lock);
 419
 420         wake_up(&server->response_q);
 421         return rc;
 422 }
 423
 424 #ifdef CONFIG_CIFS_DFS_UPCALL
 425 static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
 426 {
 427         int rc;
 428         char *hostname;
 429
 430         if (!cifs_swn_set_server_dstaddr(server)) {
 431                 if (server->hostname != target) {
 432                         hostname = extract_hostname(target);
 433                         if (!IS_ERR(hostname)) {
 434                                 spin_lock(&server->srv_lock);
 435                                 kfree(server->hostname);
 436                                 server->hostname = hostname;
 437                                 spin_unlock(&server->srv_lock);
 438                         } else {
 439                                 cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
 440                                          __func__, PTR_ERR(hostname));
 441                                 cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
 442                                          server->hostname);
 443                         }
 444                 }
 445                 /* resolve the hostname again to make sure that IP address is up-to-date. */
 446                 rc = reconn_set_ipaddr_from_hostname(server);
 447                 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
 448         }
 449         /* Reconnect the socket */
 450         if (cifs_rdma_enabled(server))
 451                 rc = smbd_reconnect(server);
 452         else
 453                 rc = generic_ip_connect(server);
 454
 455         return rc;
 456 }
 457
 458 static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
 459                                      struct dfs_cache_tgt_iterator **target_hint)
 460 {
 461         int rc;
 462         struct dfs_cache_tgt_iterator *tit;
 463
 464         *target_hint = NULL;
 465
 466         /* If dfs target list is empty, then reconnect to last server */
 467         tit = dfs_cache_get_tgt_iterator(tl);
 468         if (!tit)
 469                 return __reconnect_target_unlocked(server, server->hostname);
 470
 471         /* Otherwise, try every dfs target in @tl */
 472         for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
 473                 rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
 474                 if (!rc) {
 475                         *target_hint = tit;
 476                         break;
 477                 }
 478         }
 479         return rc;
 480 }
 481
 482 static int reconnect_dfs_server(struct TCP_Server_Info *server)
 483 {
 484         struct dfs_cache_tgt_iterator *target_hint = NULL;
 485         DFS_CACHE_TGT_LIST(tl);
 486         int num_targets = 0;
 487         int rc = 0;
 488
 489         /*
 490          * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
 491          *
 492          * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
 493          * targets (server->nr_targets).  It's also possible that the cached referral was cleared
 494          * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
 495          * refreshing the referral, so, in this case, default it to 1.
 496          */
 497         mutex_lock(&server->refpath_lock);
 498         if (!dfs_cache_noreq_find(server->leaf_fullpath + 1, NULL, &tl))
 499                 num_targets = dfs_cache_get_nr_tgts(&tl);
 500         mutex_unlock(&server->refpath_lock);
 501         if (!num_targets)
 502                 num_targets = 1;
 503
 504         if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
 505                 return 0;
 506
 507         /*
 508          * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
 509          * different server or share during failover.  It could be improved by adding some logic to
 510          * only do that in case it connects to a different server or share, though.
 511          */
 512         cifs_mark_tcp_ses_conns_for_reconnect(server, true);
 513
 514         cifs_abort_connection(server);
 515
 516         do {
 517                 try_to_freeze();
 518                 cifs_server_lock(server);
 519
 520                 rc = reconnect_target_unlocked(server, &tl, &target_hint);
 521                 if (rc) {
 522                         /* Failed to reconnect socket */
 523                         cifs_server_unlock(server);
 524                         cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
 525                         msleep(3000);
 526                         continue;
 527                 }
 528                 /*
 529                  * Socket was created.  Update tcp session status to CifsNeedNegotiate so that a
 530                  * process waiting for reconnect will know it needs to re-establish session and tcon
 531                  * through the reconnected target server.
 532                  */
 533                 atomic_inc(&tcpSesReconnectCount);
 534                 set_credits(server, 1);
 535                 spin_lock(&server->srv_lock);
 536                 if (server->tcpStatus != CifsExiting)
 537                         server->tcpStatus = CifsNeedNegotiate;
 538                 spin_unlock(&server->srv_lock);
 539                 cifs_swn_reset_server_dstaddr(server);
 540                 cifs_server_unlock(server);
 541
 542                 /* increase ref count which reconnect work will drop */
 543                 spin_lock(&cifs_tcp_ses_lock);
 544                 server->srv_count++;
 545                 spin_unlock(&cifs_tcp_ses_lock);
 546                 if (mod_delayed_work(cifsiod_wq, &server->reconnect, 0))
 547                         cifs_put_tcp_session(server, false);
 548         } while (server->tcpStatus == CifsNeedReconnect);
 549
 550         mutex_lock(&server->refpath_lock);
 551         dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, target_hint);
 552         mutex_unlock(&server->refpath_lock);
 553         dfs_cache_free_tgts(&tl);
 554
 555         /* Need to set up echo worker again once connection has been established */
 556         spin_lock(&server->srv_lock);
 557         if (server->tcpStatus == CifsNeedNegotiate)
 558                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 559         spin_unlock(&server->srv_lock);
 560
 561         wake_up(&server->response_q);
 562         return rc;
 563 }
 564
 565 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 566 {
 567         mutex_lock(&server->refpath_lock);
 568         if (!server->leaf_fullpath) {
 569                 mutex_unlock(&server->refpath_lock);
 570                 return __cifs_reconnect(server, mark_smb_session);
 571         }
 572         mutex_unlock(&server->refpath_lock);
 573
 574         return reconnect_dfs_server(server);
 575 }
 576 #else
 577 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 578 {
 579         return __cifs_reconnect(server, mark_smb_session);
 580 }
 581 #endif
 582
 583 static void
 584 cifs_echo_request(struct work_struct *work)
 585 {
 586         int rc;
 587         struct TCP_Server_Info *server = container_of(work,
 588                                         struct TCP_Server_Info, echo.work);
 589
 590         /*
 591          * We cannot send an echo if it is disabled.
 592          * Also, no need to ping if we got a response recently.
 593          */
 594
 595         if (server->tcpStatus == CifsNeedReconnect ||
 596             server->tcpStatus == CifsExiting ||
 597             server->tcpStatus == CifsNew ||
 598             (server->ops->can_echo && !server->ops->can_echo(server)) ||
 599             time_before(jiffies, server->lstrp + server->echo_interval - HZ))
 600                 goto requeue_echo;
 601
 602         rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
 603         cifs_server_dbg(FYI, "send echo request: rc = %d\n", rc);
 604
 605         /* Check witness registrations */
 606         cifs_swn_check();
 607
 608 requeue_echo:
 609         queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
 610 }
 611
 612 static bool
 613 allocate_buffers(struct TCP_Server_Info *server)
 614 {
 615         if (!server->bigbuf) {
 616                 server->bigbuf = (char *)cifs_buf_get();
 617                 if (!server->bigbuf) {
 618                         cifs_server_dbg(VFS, "No memory for large SMB response\n");
 619                         msleep(3000);
 620                         /* retry will check if exiting */
 621                         return false;
 622                 }
 623         } else if (server->large_buf) {
 624                 /* we are reusing a dirty large buf, clear its start */
 625                 memset(server->bigbuf, 0, HEADER_SIZE(server));
 626         }
 627
 628         if (!server->smallbuf) {
 629                 server->smallbuf = (char *)cifs_small_buf_get();
 630                 if (!server->smallbuf) {
 631                         cifs_server_dbg(VFS, "No memory for SMB response\n");
 632                         msleep(1000);
 633                         /* retry will check if exiting */
 634                         return false;
 635                 }
 636                 /* beginning of smb buffer is cleared in our buf_get */
 637         } else {
 638                 /* if existing small buf clear beginning */
 639                 memset(server->smallbuf, 0, HEADER_SIZE(server));
 640         }
 641
 642         return true;
 643 }
 644
 645 static bool
 646 server_unresponsive(struct TCP_Server_Info *server)
 647 {
 648         /*
 649          * We need to wait 3 echo intervals to make sure we handle such
 650          * situations right:
 651          * 1s  client sends a normal SMB request
 652          * 2s  client gets a response
 653          * 30s echo workqueue job pops, and decides we got a response recently
 654          *     and don't need to send another
 655          * ...
 656          * 65s kernel_recvmsg times out, and we see that we haven't gotten
 657          *     a response in >60s.
 658          */
 659         spin_lock(&server->srv_lock);
 660         if ((server->tcpStatus == CifsGood ||
 661             server->tcpStatus == CifsNeedNegotiate) &&
 662             (!server->ops->can_echo || server->ops->can_echo(server)) &&
 663             time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
 664                 spin_unlock(&server->srv_lock);
 665                 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
 666                          (3 * server->echo_interval) / HZ);
 667                 cifs_reconnect(server, false);
 668                 return true;
 669         }
 670         spin_unlock(&server->srv_lock);
 671
 672         return false;
 673 }
 674
 675 static inline bool
 676 zero_credits(struct TCP_Server_Info *server)
 677 {
 678         int val;
 679
 680         spin_lock(&server->req_lock);
 681         val = server->credits + server->echo_credits + server->oplock_credits;
 682         if (server->in_flight == 0 && val == 0) {
 683                 spin_unlock(&server->req_lock);
 684                 return true;
 685         }
 686         spin_unlock(&server->req_lock);
 687         return false;
 688 }
 689
 690 static int
 691 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 692 {
 693         int length = 0;
 694         int total_read;
 695
 696         for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 697                 try_to_freeze();
 698
 699                 /* reconnect if no credits and no requests in flight */
 700                 if (zero_credits(server)) {
 701                         cifs_reconnect(server, false);
 702                         return -ECONNABORTED;
 703                 }
 704
 705                 if (server_unresponsive(server))
 706                         return -ECONNABORTED;
 707                 if (cifs_rdma_enabled(server) && server->smbd_conn)
 708                         length = smbd_recv(server->smbd_conn, smb_msg);
 709                 else
 710                         length = sock_recvmsg(server->ssocket, smb_msg, 0);
 711
 712                 spin_lock(&server->srv_lock);
 713                 if (server->tcpStatus == CifsExiting) {
 714                         spin_unlock(&server->srv_lock);
 715                         return -ESHUTDOWN;
 716                 }
 717
 718                 if (server->tcpStatus == CifsNeedReconnect) {
 719                         spin_unlock(&server->srv_lock);
 720                         cifs_reconnect(server, false);
 721                         return -ECONNABORTED;
 722                 }
 723                 spin_unlock(&server->srv_lock);
 724
 725                 if (length == -ERESTARTSYS ||
 726                     length == -EAGAIN ||
 727                     length == -EINTR) {
 728                         /*
 729                          * Minimum sleep to prevent looping, allowing socket
 730                          * to clear and app threads to set tcpStatus
 731                          * CifsNeedReconnect if server hung.
 732                          */
 733                         usleep_range(1000, 2000);
 734                         length = 0;
 735                         continue;
 736                 }
 737
 738                 if (length <= 0) {
 739                         cifs_dbg(FYI, "Received no data or error: %d\n", length);
 740                         cifs_reconnect(server, false);
 741                         return -ECONNABORTED;
 742                 }
 743         }
 744         return total_read;
 745 }
 746
 747 int
 748 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 749                       unsigned int to_read)
 750 {
 751         struct msghdr smb_msg = {};
 752         struct kvec iov = {.iov_base = buf, .iov_len = to_read};
 753         iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
 754
 755         return cifs_readv_from_socket(server, &smb_msg);
 756 }
 757
 758 ssize_t
 759 cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
 760 {
 761         struct msghdr smb_msg = {};
 762
 763         /*
 764          *  iov_iter_discard already sets smb_msg.type and count and iov_offset
 765          *  and cifs_readv_from_socket sets msg_control and msg_controllen
 766          *  so little to initialize in struct msghdr
 767          */
 768         iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
 769
 770         return cifs_readv_from_socket(server, &smb_msg);
 771 }
 772
 773 int
 774 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 775         unsigned int page_offset, unsigned int to_read)
 776 {
 777         struct msghdr smb_msg = {};
 778         struct bio_vec bv;
 779
 780         bvec_set_page(&bv, page, to_read, page_offset);
 781         iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
 782         return cifs_readv_from_socket(server, &smb_msg);
 783 }
 784
 785 int
 786 cifs_read_iter_from_socket(struct TCP_Server_Info *server, struct iov_iter *iter,
 787                            unsigned int to_read)
 788 {
 789         struct msghdr smb_msg = { .msg_iter = *iter };
 790         int ret;
 791
 792         iov_iter_truncate(&smb_msg.msg_iter, to_read);
 793         ret = cifs_readv_from_socket(server, &smb_msg);
 794         if (ret > 0)
 795                 iov_iter_advance(iter, ret);
 796         return ret;
 797 }
 798
 799 static bool
 800 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
 801 {
 802         /*
 803          * The first byte big endian of the length field,
 804          * is actually not part of the length but the type
 805          * with the most common, zero, as regular data.
 806          */
 807         switch (type) {
 808         case RFC1002_SESSION_MESSAGE:
 809                 /* Regular SMB response */
 810                 return true;
 811         case RFC1002_SESSION_KEEP_ALIVE:
 812                 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
 813                 break;
 814         case RFC1002_POSITIVE_SESSION_RESPONSE:
 815                 cifs_dbg(FYI, "RFC 1002 positive session response\n");
 816                 break;
 817         case RFC1002_NEGATIVE_SESSION_RESPONSE:
 818                 /*
 819                  * We get this from Windows 98 instead of an error on
 820                  * SMB negprot response.
 821                  */
 822                 cifs_dbg(FYI, "RFC 1002 negative session response\n");
 823                 /* give server a second to clean up */
 824                 msleep(1000);
 825                 /*
 826                  * Always try 445 first on reconnect since we get NACK
 827                  * on some if we ever connected to port 139 (the NACK
 828                  * is since we do not begin with RFC1001 session
 829                  * initialize frame).
 830                  */
 831                 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
 832                 cifs_reconnect(server, true);
 833                 break;
 834         default:
 835                 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
 836                 cifs_reconnect(server, true);
 837         }
 838
 839         return false;
 840 }
 841
 842 void
 843 dequeue_mid(struct mid_q_entry *mid, bool malformed)
 844 {
 845 #ifdef CONFIG_CIFS_STATS2
 846         mid->when_received = jiffies;
 847 #endif
 848         spin_lock(&mid->server->mid_lock);
 849         if (!malformed)
 850                 mid->mid_state = MID_RESPONSE_RECEIVED;
 851         else
 852                 mid->mid_state = MID_RESPONSE_MALFORMED;
 853         /*
 854          * Trying to handle/dequeue a mid after the send_recv()
 855          * function has finished processing it is a bug.
 856          */
 857         if (mid->mid_flags & MID_DELETED) {
 858                 spin_unlock(&mid->server->mid_lock);
 859                 pr_warn_once("trying to dequeue a deleted mid\n");
 860         } else {
 861                 list_del_init(&mid->qhead);
 862                 mid->mid_flags |= MID_DELETED;
 863                 spin_unlock(&mid->server->mid_lock);
 864         }
 865 }
 866
 867 static unsigned int
 868 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 869 {
 870         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
 871
 872         /*
 873          * SMB1 does not use credits.
 874          */
 875         if (is_smb1(server))
 876                 return 0;
 877
 878         return le16_to_cpu(shdr->CreditRequest);
 879 }
 880
 881 static void
 882 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 883            char *buf, int malformed)
 884 {
 885         if (server->ops->check_trans2 &&
 886             server->ops->check_trans2(mid, server, buf, malformed))
 887                 return;
 888         mid->credits_received = smb2_get_credits_from_hdr(buf, server);
 889         mid->resp_buf = buf;
 890         mid->large_buf = server->large_buf;
 891         /* Was previous buf put in mpx struct for multi-rsp? */
 892         if (!mid->multiRsp) {
 893                 /* smb buffer will be freed by user thread */
 894                 if (server->large_buf)
 895                         server->bigbuf = NULL;
 896                 else
 897                         server->smallbuf = NULL;
 898         }
 899         dequeue_mid(mid, malformed);
 900 }
 901
 902 int
 903 cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
 904 {
 905         bool srv_sign_required = server->sec_mode & server->vals->signing_required;
 906         bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
 907         bool mnt_sign_enabled;
 908
 909         /*
 910          * Is signing required by mnt options? If not then check
 911          * global_secflags to see if it is there.
 912          */
 913         if (!mnt_sign_required)
 914                 mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
 915                                                 CIFSSEC_MUST_SIGN);
 916
 917         /*
 918          * If signing is required then it's automatically enabled too,
 919          * otherwise, check to see if the secflags allow it.
 920          */
 921         mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
 922                                 (global_secflags & CIFSSEC_MAY_SIGN);
 923
 924         /* If server requires signing, does client allow it? */
 925         if (srv_sign_required) {
 926                 if (!mnt_sign_enabled) {
 927                         cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
 928                         return -EOPNOTSUPP;
 929                 }
 930                 server->sign = true;
 931         }
 932
 933         /* If client requires signing, does server allow it? */
 934         if (mnt_sign_required) {
 935                 if (!srv_sign_enabled) {
 936                         cifs_dbg(VFS, "Server does not support signing!\n");
 937                         return -EOPNOTSUPP;
 938                 }
 939                 server->sign = true;
 940         }
 941
 942         if (cifs_rdma_enabled(server) && server->sign)
 943                 cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
 944
 945         return 0;
 946 }
 947
 948 static noinline_for_stack void
 949 clean_demultiplex_info(struct TCP_Server_Info *server)
 950 {
 951         int length;
 952
 953         /* take it off the list, if it's not already */
 954         spin_lock(&server->srv_lock);
 955         list_del_init(&server->tcp_ses_list);
 956         spin_unlock(&server->srv_lock);
 957
 958         cancel_delayed_work_sync(&server->echo);
 959
 960         spin_lock(&server->srv_lock);
 961         server->tcpStatus = CifsExiting;
 962         spin_unlock(&server->srv_lock);
 963         wake_up_all(&server->response_q);
 964
 965         /* check if we have blocked requests that need to free */
 966         spin_lock(&server->req_lock);
 967         if (server->credits <= 0)
 968                 server->credits = 1;
 969         spin_unlock(&server->req_lock);
 970         /*
 971          * Although there should not be any requests blocked on this queue it
 972          * can not hurt to be paranoid and try to wake up requests that may
 973          * haven been blocked when more than 50 at time were on the wire to the
 974          * same server - they now will see the session is in exit state and get
 975          * out of SendReceive.
 976          */
 977         wake_up_all(&server->request_q);
 978         /* give those requests time to exit */
 979         msleep(125);
 980         if (cifs_rdma_enabled(server))
 981                 smbd_destroy(server);
 982         if (server->ssocket) {
 983                 sock_release(server->ssocket);
 984                 server->ssocket = NULL;
 985         }
 986
 987         if (!list_empty(&server->pending_mid_q)) {
 988                 struct list_head dispose_list;
 989                 struct mid_q_entry *mid_entry;
 990                 struct list_head *tmp, *tmp2;
 991
 992                 INIT_LIST_HEAD(&dispose_list);
 993                 spin_lock(&server->mid_lock);
 994                 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 995                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 996                         cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
 997                         kref_get(&mid_entry->refcount);
 998                         mid_entry->mid_state = MID_SHUTDOWN;
 999                         list_move(&mid_entry->qhead, &dispose_list);
1000                         mid_entry->mid_flags |= MID_DELETED;
1001                 }
1002                 spin_unlock(&server->mid_lock);
1003
1004                 /* now walk dispose list and issue callbacks */
1005                 list_for_each_safe(tmp, tmp2, &dispose_list) {
1006                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
1007                         cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
1008                         list_del_init(&mid_entry->qhead);
1009                         mid_entry->callback(mid_entry);
1010                         release_mid(mid_entry);
1011                 }
1012                 /* 1/8th of sec is more than enough time for them to exit */
1013                 msleep(125);
1014         }
1015
1016         if (!list_empty(&server->pending_mid_q)) {
1017                 /*
1018                  * mpx threads have not exited yet give them at least the smb
1019                  * send timeout time for long ops.
1020                  *
1021                  * Due to delays on oplock break requests, we need to wait at
1022                  * least 45 seconds before giving up on a request getting a
1023                  * response and going ahead and killing cifsd.
1024                  */
1025                 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
1026                 msleep(46000);
1027                 /*
1028                  * If threads still have not exited they are probably never
1029                  * coming home not much else we can do but free the memory.
1030                  */
1031         }
1032
1033         kfree(server->leaf_fullpath);
1034         kfree(server);
1035
1036         length = atomic_dec_return(&tcpSesAllocCount);
1037         if (length > 0)
1038                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1039 }
1040
1041 static int
1042 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1043 {
1044         int length;
1045         char *buf = server->smallbuf;
1046         unsigned int pdu_length = server->pdu_size;
1047
1048         /* make sure this will fit in a large buffer */
1049         if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1050             HEADER_PREAMBLE_SIZE(server)) {
1051                 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1052                 cifs_reconnect(server, true);
1053                 return -ECONNABORTED;
1054         }
1055
1056         /* switch to large buffer if too big for a small one */
1057         if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1058                 server->large_buf = true;
1059                 memcpy(server->bigbuf, buf, server->total_read);
1060                 buf = server->bigbuf;
1061         }
1062
1063         /* now read the rest */
1064         length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1065                                        pdu_length - MID_HEADER_SIZE(server));
1066
1067         if (length < 0)
1068                 return length;
1069         server->total_read += length;
1070
1071         dump_smb(buf, server->total_read);
1072
1073         return cifs_handle_standard(server, mid);
1074 }
1075
1076 int
1077 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1078 {
1079         char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1080         int rc;
1081
1082         /*
1083          * We know that we received enough to get to the MID as we
1084          * checked the pdu_length earlier. Now check to see
1085          * if the rest of the header is OK.
1086          *
1087          * 48 bytes is enough to display the header and a little bit
1088          * into the payload for debugging purposes.
1089          */
1090         rc = server->ops->check_message(buf, server->total_read, server);
1091         if (rc)
1092                 cifs_dump_mem("Bad SMB: ", buf,
1093                         min_t(unsigned int, server->total_read, 48));
1094
1095         if (server->ops->is_session_expired &&
1096             server->ops->is_session_expired(buf)) {
1097                 cifs_reconnect(server, true);
1098                 return -1;
1099         }
1100
1101         if (server->ops->is_status_pending &&
1102             server->ops->is_status_pending(buf, server))
1103                 return -1;
1104
1105         if (!mid)
1106                 return rc;
1107
1108         handle_mid(mid, server, buf, rc);
1109         return 0;
1110 }
1111
1112 static void
1113 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1114 {
1115         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
1116         int scredits, in_flight;
1117
1118         /*
1119          * SMB1 does not use credits.
1120          */
1121         if (is_smb1(server))
1122                 return;
1123
1124         if (shdr->CreditRequest) {
1125                 spin_lock(&server->req_lock);
1126                 server->credits += le16_to_cpu(shdr->CreditRequest);
1127                 scredits = server->credits;
1128                 in_flight = server->in_flight;
1129                 spin_unlock(&server->req_lock);
1130                 wake_up(&server->request_q);
1131
1132                 trace_smb3_hdr_credits(server->CurrentMid,
1133                                 server->conn_id, server->hostname, scredits,
1134                                 le16_to_cpu(shdr->CreditRequest), in_flight);
1135                 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
1136                                 __func__, le16_to_cpu(shdr->CreditRequest),
1137                                 scredits);
1138         }
1139 }
1140
1141
1142 static int
1143 cifs_demultiplex_thread(void *p)
1144 {
1145         int i, num_mids, length;
1146         struct TCP_Server_Info *server = p;
1147         unsigned int pdu_length;
1148         unsigned int next_offset;
1149         char *buf = NULL;
1150         struct task_struct *task_to_wake = NULL;
1151         struct mid_q_entry *mids[MAX_COMPOUND];
1152         char *bufs[MAX_COMPOUND];
1153         unsigned int noreclaim_flag, num_io_timeout = 0;
1154         bool pending_reconnect = false;
1155
1156         noreclaim_flag = memalloc_noreclaim_save();
1157         cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1158
1159         length = atomic_inc_return(&tcpSesAllocCount);
1160         if (length > 1)
1161                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1162
1163         set_freezable();
1164         allow_kernel_signal(SIGKILL);
1165         while (server->tcpStatus != CifsExiting) {
1166                 if (try_to_freeze())
1167                         continue;
1168
1169                 if (!allocate_buffers(server))
1170                         continue;
1171
1172                 server->large_buf = false;
1173                 buf = server->smallbuf;
1174                 pdu_length = 4; /* enough to get RFC1001 header */
1175
1176                 length = cifs_read_from_socket(server, buf, pdu_length);
1177                 if (length < 0)
1178                         continue;
1179
1180                 if (is_smb1(server))
1181                         server->total_read = length;
1182                 else
1183                         server->total_read = 0;
1184
1185                 /*
1186                  * The right amount was read from socket - 4 bytes,
1187                  * so we can now interpret the length field.
1188                  */
1189                 pdu_length = get_rfc1002_length(buf);
1190
1191                 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1192                 if (!is_smb_response(server, buf[0]))
1193                         continue;
1194
1195                 pending_reconnect = false;
1196 next_pdu:
1197                 server->pdu_size = pdu_length;
1198
1199                 /* make sure we have enough to get to the MID */
1200                 if (server->pdu_size < MID_HEADER_SIZE(server)) {
1201                         cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1202                                  server->pdu_size);
1203                         cifs_reconnect(server, true);
1204                         continue;
1205                 }
1206
1207                 /* read down to the MID */
1208                 length = cifs_read_from_socket(server,
1209                              buf + HEADER_PREAMBLE_SIZE(server),
1210                              MID_HEADER_SIZE(server));
1211                 if (length < 0)
1212                         continue;
1213                 server->total_read += length;
1214
1215                 if (server->ops->next_header) {
1216                         next_offset = server->ops->next_header(buf);
1217                         if (next_offset)
1218                                 server->pdu_size = next_offset;
1219                 }
1220
1221                 memset(mids, 0, sizeof(mids));
1222                 memset(bufs, 0, sizeof(bufs));
1223                 num_mids = 0;
1224
1225                 if (server->ops->is_transform_hdr &&
1226                     server->ops->receive_transform &&
1227                     server->ops->is_transform_hdr(buf)) {
1228                         length = server->ops->receive_transform(server,
1229                                                                 mids,
1230                                                                 bufs,
1231                                                                 &num_mids);
1232                 } else {
1233                         mids[0] = server->ops->find_mid(server, buf);
1234                         bufs[0] = buf;
1235                         num_mids = 1;
1236
1237                         if (!mids[0] || !mids[0]->receive)
1238                                 length = standard_receive3(server, mids[0]);
1239                         else
1240                                 length = mids[0]->receive(server, mids[0]);
1241                 }
1242
1243                 if (length < 0) {
1244                         for (i = 0; i < num_mids; i++)
1245                                 if (mids[i])
1246                                         release_mid(mids[i]);
1247                         continue;
1248                 }
1249
1250                 if (server->ops->is_status_io_timeout &&
1251                     server->ops->is_status_io_timeout(buf)) {
1252                         num_io_timeout++;
1253                         if (num_io_timeout > MAX_STATUS_IO_TIMEOUT) {
1254                                 cifs_server_dbg(VFS,
1255                                                 "Number of request timeouts exceeded %d. Reconnecting",
1256                                                 MAX_STATUS_IO_TIMEOUT);
1257
1258                                 pending_reconnect = true;
1259                                 num_io_timeout = 0;
1260                         }
1261                 }
1262
1263                 server->lstrp = jiffies;
1264
1265                 for (i = 0; i < num_mids; i++) {
1266                         if (mids[i] != NULL) {
1267                                 mids[i]->resp_buf_size = server->pdu_size;
1268
1269                                 if (bufs[i] != NULL) {
1270                                         if (server->ops->is_network_name_deleted &&
1271                                             server->ops->is_network_name_deleted(bufs[i],
1272                                                                                  server)) {
1273                                                 cifs_server_dbg(FYI,
1274                                                                 "Share deleted. Reconnect needed");
1275                                         }
1276                                 }
1277
1278                                 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1279                                         mids[i]->callback(mids[i]);
1280
1281                                 release_mid(mids[i]);
1282                         } else if (server->ops->is_oplock_break &&
1283                                    server->ops->is_oplock_break(bufs[i],
1284                                                                 server)) {
1285                                 smb2_add_credits_from_hdr(bufs[i], server);
1286                                 cifs_dbg(FYI, "Received oplock break\n");
1287                         } else {
1288                                 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1289                                                 atomic_read(&mid_count));
1290                                 cifs_dump_mem("Received Data is: ", bufs[i],
1291                                               HEADER_SIZE(server));
1292                                 smb2_add_credits_from_hdr(bufs[i], server);
1293 #ifdef CONFIG_CIFS_DEBUG2
1294                                 if (server->ops->dump_detail)
1295                                         server->ops->dump_detail(bufs[i],
1296                                                                  server);
1297                                 cifs_dump_mids(server);
1298 #endif /* CIFS_DEBUG2 */
1299                         }
1300                 }
1301
1302                 if (pdu_length > server->pdu_size) {
1303                         if (!allocate_buffers(server))
1304                                 continue;
1305                         pdu_length -= server->pdu_size;
1306                         server->total_read = 0;
1307                         server->large_buf = false;
1308                         buf = server->smallbuf;
1309                         goto next_pdu;
1310                 }
1311
1312                 /* do this reconnect at the very end after processing all MIDs */
1313                 if (pending_reconnect)
1314                         cifs_reconnect(server, true);
1315
1316         } /* end while !EXITING */
1317
1318         /* buffer usually freed in free_mid - need to free it here on exit */
1319         cifs_buf_release(server->bigbuf);
1320         if (server->smallbuf) /* no sense logging a debug message if NULL */
1321                 cifs_small_buf_release(server->smallbuf);
1322
1323         task_to_wake = xchg(&server->tsk, NULL);
1324         clean_demultiplex_info(server);
1325
1326         /* if server->tsk was NULL then wait for a signal before exiting */
1327         if (!task_to_wake) {
1328                 set_current_state(TASK_INTERRUPTIBLE);
1329                 while (!signal_pending(current)) {
1330                         schedule();
1331                         set_current_state(TASK_INTERRUPTIBLE);
1332                 }
1333                 set_current_state(TASK_RUNNING);
1334         }
1335
1336         memalloc_noreclaim_restore(noreclaim_flag);
1337         module_put_and_kthread_exit(0);
1338 }
1339
1340 int
1341 cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
1342 {
1343         struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1344         struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1345         struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1346         struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1347
1348         switch (srcaddr->sa_family) {
1349         case AF_UNSPEC:
1350                 switch (rhs->sa_family) {
1351                 case AF_UNSPEC:
1352                         return 0;
1353                 case AF_INET:
1354                 case AF_INET6:
1355                         return 1;
1356                 default:
1357                         return -1;
1358                 }
1359         case AF_INET: {
1360                 switch (rhs->sa_family) {
1361                 case AF_UNSPEC:
1362                         return -1;
1363                 case AF_INET:
1364                         return memcmp(saddr4, vaddr4,
1365                                       sizeof(struct sockaddr_in));
1366                 case AF_INET6:
1367                         return 1;
1368                 default:
1369                         return -1;
1370                 }
1371         }
1372         case AF_INET6: {
1373                 switch (rhs->sa_family) {
1374                 case AF_UNSPEC:
1375                 case AF_INET:
1376                         return -1;
1377                 case AF_INET6:
1378                         return memcmp(saddr6,
1379                                       vaddr6,
1380                                       sizeof(struct sockaddr_in6));
1381                 default:
1382                         return -1;
1383                 }
1384         }
1385         default:
1386                 return -1; /* don't expect to be here */
1387         }
1388 }
1389
1390 /*
1391  * Returns true if srcaddr isn't specified and rhs isn't specified, or
1392  * if srcaddr is specified and matches the IP address of the rhs argument
1393  */
1394 bool
1395 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1396 {
1397         switch (srcaddr->sa_family) {
1398         case AF_UNSPEC:
1399                 return (rhs->sa_family == AF_UNSPEC);
1400         case AF_INET: {
1401                 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1402                 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1403                 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1404         }
1405         case AF_INET6: {
1406                 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1407                 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1408                 return (ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr)
1409                         && saddr6->sin6_scope_id == vaddr6->sin6_scope_id);
1410         }
1411         default:
1412                 WARN_ON(1);
1413                 return false; /* don't expect to be here */
1414         }
1415 }
1416
1417 /*
1418  * If no port is specified in addr structure, we try to match with 445 port
1419  * and if it fails - with 139 ports. It should be called only if address
1420  * families of server and addr are equal.
1421  */
1422 static bool
1423 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1424 {
1425         __be16 port, *sport;
1426
1427         /* SMBDirect manages its own ports, don't match it here */
1428         if (server->rdma)
1429                 return true;
1430
1431         switch (addr->sa_family) {
1432         case AF_INET:
1433                 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1434                 port = ((struct sockaddr_in *) addr)->sin_port;
1435                 break;
1436         case AF_INET6:
1437                 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1438                 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1439                 break;
1440         default:
1441                 WARN_ON(1);
1442                 return false;
1443         }
1444
1445         if (!port) {
1446                 port = htons(CIFS_PORT);
1447                 if (port == *sport)
1448                         return true;
1449
1450                 port = htons(RFC1001_PORT);
1451         }
1452
1453         return port == *sport;
1454 }
1455
1456 static bool match_server_address(struct TCP_Server_Info *server, struct sockaddr *addr)
1457 {
1458         if (!cifs_match_ipaddr(addr, (struct sockaddr *)&server->dstaddr))
1459                 return false;
1460
1461         return true;
1462 }
1463
1464 static bool
1465 match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1466 {
1467         /*
1468          * The select_sectype function should either return the ctx->sectype
1469          * that was specified, or "Unspecified" if that sectype was not
1470          * compatible with the given NEGOTIATE request.
1471          */
1472         if (server->ops->select_sectype(server, ctx->sectype)
1473              == Unspecified)
1474                 return false;
1475
1476         /*
1477          * Now check if signing mode is acceptable. No need to check
1478          * global_secflags at this point since if MUST_SIGN is set then
1479          * the server->sign had better be too.
1480          */
1481         if (ctx->sign && !server->sign)
1482                 return false;
1483
1484         return true;
1485 }
1486
1487 /* this function must be called with srv_lock held */
1488 static int match_server(struct TCP_Server_Info *server,
1489                         struct smb3_fs_context *ctx,
1490                         bool match_super)
1491 {
1492         struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1493
1494         lockdep_assert_held(&server->srv_lock);
1495
1496         if (ctx->nosharesock)
1497                 return 0;
1498
1499         /* this server does not share socket */
1500         if (server->nosharesock)
1501                 return 0;
1502
1503         /* If multidialect negotiation see if existing sessions match one */
1504         if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1505                 if (server->vals->protocol_id < SMB30_PROT_ID)
1506                         return 0;
1507         } else if (strcmp(ctx->vals->version_string,
1508                    SMBDEFAULT_VERSION_STRING) == 0) {
1509                 if (server->vals->protocol_id < SMB21_PROT_ID)
1510                         return 0;
1511         } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1512                 return 0;
1513
1514         if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1515                 return 0;
1516
1517         if (!cifs_match_ipaddr((struct sockaddr *)&ctx->srcaddr,
1518                                (struct sockaddr *)&server->srcaddr))
1519                 return 0;
1520         /*
1521          * When matching cifs.ko superblocks (@match_super == true), we can't
1522          * really match either @server->leaf_fullpath or @server->dstaddr
1523          * directly since this @server might belong to a completely different
1524          * server -- in case of domain-based DFS referrals or DFS links -- as
1525          * provided earlier by mount(2) through 'source' and 'ip' options.
1526          *
1527          * Otherwise, match the DFS referral in @server->leaf_fullpath or the
1528          * destination address in @server->dstaddr.
1529          *
1530          * When using 'nodfs' mount option, we avoid sharing it with DFS
1531          * connections as they might failover.
1532          */
1533         if (!match_super) {
1534                 if (!ctx->nodfs) {
1535                         if (server->leaf_fullpath) {
1536                                 if (!ctx->leaf_fullpath ||
1537                                     strcasecmp(server->leaf_fullpath,
1538                                                ctx->leaf_fullpath))
1539                                         return 0;
1540                         } else if (ctx->leaf_fullpath) {
1541                                 return 0;
1542                         }
1543                 } else if (server->leaf_fullpath) {
1544                         return 0;
1545                 }
1546         }
1547
1548         /*
1549          * Match for a regular connection (address/hostname/port) which has no
1550          * DFS referrals set.
1551          */
1552         if (!server->leaf_fullpath &&
1553             (strcasecmp(server->hostname, ctx->server_hostname) ||
1554              !match_server_address(server, addr) ||
1555              !match_port(server, addr)))
1556                 return 0;
1557
1558         if (!match_security(server, ctx))
1559                 return 0;
1560
1561         if (server->echo_interval != ctx->echo_interval * HZ)
1562                 return 0;
1563
1564         if (server->rdma != ctx->rdma)
1565                 return 0;
1566
1567         if (server->ignore_signature != ctx->ignore_signature)
1568                 return 0;
1569
1570         if (server->min_offload != ctx->min_offload)
1571                 return 0;
1572
1573         return 1;
1574 }
1575
1576 struct TCP_Server_Info *
1577 cifs_find_tcp_session(struct smb3_fs_context *ctx)
1578 {
1579         struct TCP_Server_Info *server;
1580
1581         spin_lock(&cifs_tcp_ses_lock);
1582         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1583                 spin_lock(&server->srv_lock);
1584                 /*
1585                  * Skip ses channels since they're only handled in lower layers
1586                  * (e.g. cifs_send_recv).
1587                  */
1588                 if (SERVER_IS_CHAN(server) ||
1589                     !match_server(server, ctx, false)) {
1590                         spin_unlock(&server->srv_lock);
1591                         continue;
1592                 }
1593                 spin_unlock(&server->srv_lock);
1594
1595                 ++server->srv_count;
1596                 spin_unlock(&cifs_tcp_ses_lock);
1597                 cifs_dbg(FYI, "Existing tcp session with server found\n");
1598                 return server;
1599         }
1600         spin_unlock(&cifs_tcp_ses_lock);
1601         return NULL;
1602 }
1603
1604 void
1605 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1606 {
1607         struct task_struct *task;
1608
1609         spin_lock(&cifs_tcp_ses_lock);
1610         if (--server->srv_count > 0) {
1611                 spin_unlock(&cifs_tcp_ses_lock);
1612                 return;
1613         }
1614
1615         /* srv_count can never go negative */
1616         WARN_ON(server->srv_count < 0);
1617
1618         put_net(cifs_net_ns(server));
1619
1620         list_del_init(&server->tcp_ses_list);
1621         spin_unlock(&cifs_tcp_ses_lock);
1622
1623         /* For secondary channels, we pick up ref-count on the primary server */
1624         if (SERVER_IS_CHAN(server))
1625                 cifs_put_tcp_session(server->primary_server, from_reconnect);
1626
1627         cancel_delayed_work_sync(&server->echo);
1628
1629         if (from_reconnect) {
1630                 /*
1631                  * Avoid deadlock here: reconnect work calls
1632                  * cifs_put_tcp_session() at its end. Need to be sure
1633                  * that reconnect work does nothing with server pointer after
1634                  * that step.
1635                  */
1636                 if (cancel_delayed_work(&server->reconnect))
1637                         cifs_put_tcp_session(server, from_reconnect);
1638         } else {
1639                 if (cancel_delayed_work_sync(&server->reconnect))
1640                         cifs_put_tcp_session(server, from_reconnect);
1641         }
1642
1643         spin_lock(&server->srv_lock);
1644         server->tcpStatus = CifsExiting;
1645         spin_unlock(&server->srv_lock);
1646
1647         cifs_crypto_secmech_release(server);
1648
1649         kfree_sensitive(server->session_key.response);
1650         server->session_key.response = NULL;
1651         server->session_key.len = 0;
1652         kfree(server->hostname);
1653         server->hostname = NULL;
1654
1655         task = xchg(&server->tsk, NULL);
1656         if (task)
1657                 send_sig(SIGKILL, task, 1);
1658 }
1659
1660 struct TCP_Server_Info *
1661 cifs_get_tcp_session(struct smb3_fs_context *ctx,
1662                      struct TCP_Server_Info *primary_server)
1663 {
1664         struct TCP_Server_Info *tcp_ses = NULL;
1665         int rc;
1666
1667         cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1668
1669         /* see if we already have a matching tcp_ses */
1670         tcp_ses = cifs_find_tcp_session(ctx);
1671         if (tcp_ses)
1672                 return tcp_ses;
1673
1674         tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1675         if (!tcp_ses) {
1676                 rc = -ENOMEM;
1677                 goto out_err;
1678         }
1679
1680         tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
1681         if (!tcp_ses->hostname) {
1682                 rc = -ENOMEM;
1683                 goto out_err;
1684         }
1685
1686         if (ctx->leaf_fullpath) {
1687                 tcp_ses->leaf_fullpath = kstrdup(ctx->leaf_fullpath, GFP_KERNEL);
1688                 if (!tcp_ses->leaf_fullpath) {
1689                         rc = -ENOMEM;
1690                         goto out_err;
1691                 }
1692         }
1693
1694         if (ctx->nosharesock)
1695                 tcp_ses->nosharesock = true;
1696
1697         tcp_ses->ops = ctx->ops;
1698         tcp_ses->vals = ctx->vals;
1699         cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1700
1701         tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1702         tcp_ses->noblockcnt = ctx->rootfs;
1703         tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1704         tcp_ses->noautotune = ctx->noautotune;
1705         tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1706         tcp_ses->rdma = ctx->rdma;
1707         tcp_ses->in_flight = 0;
1708         tcp_ses->max_in_flight = 0;
1709         tcp_ses->credits = 1;
1710         if (primary_server) {
1711                 spin_lock(&cifs_tcp_ses_lock);
1712                 ++primary_server->srv_count;
1713                 spin_unlock(&cifs_tcp_ses_lock);
1714                 tcp_ses->primary_server = primary_server;
1715         }
1716         init_waitqueue_head(&tcp_ses->response_q);
1717         init_waitqueue_head(&tcp_ses->request_q);
1718         INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1719         mutex_init(&tcp_ses->_srv_mutex);
1720         memcpy(tcp_ses->workstation_RFC1001_name,
1721                 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1722         memcpy(tcp_ses->server_RFC1001_name,
1723                 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1724         tcp_ses->session_estab = false;
1725         tcp_ses->sequence_number = 0;
1726         tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
1727         tcp_ses->reconnect_instance = 1;
1728         tcp_ses->lstrp = jiffies;
1729         tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1730         spin_lock_init(&tcp_ses->req_lock);
1731         spin_lock_init(&tcp_ses->srv_lock);
1732         spin_lock_init(&tcp_ses->mid_lock);
1733         INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1734         INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1735         INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1736         INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1737         mutex_init(&tcp_ses->reconnect_mutex);
1738 #ifdef CONFIG_CIFS_DFS_UPCALL
1739         mutex_init(&tcp_ses->refpath_lock);
1740 #endif
1741         memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1742                sizeof(tcp_ses->srcaddr));
1743         memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1744                 sizeof(tcp_ses->dstaddr));
1745         if (ctx->use_client_guid)
1746                 memcpy(tcp_ses->client_guid, ctx->client_guid,
1747                        SMB2_CLIENT_GUID_SIZE);
1748         else
1749                 generate_random_uuid(tcp_ses->client_guid);
1750         /*
1751          * at this point we are the only ones with the pointer
1752          * to the struct since the kernel thread not created yet
1753          * no need to spinlock this init of tcpStatus or srv_count
1754          */
1755         tcp_ses->tcpStatus = CifsNew;
1756         ++tcp_ses->srv_count;
1757
1758         if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1759                 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1760                 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1761         else
1762                 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1763         if (tcp_ses->rdma) {
1764 #ifndef CONFIG_CIFS_SMB_DIRECT
1765                 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1766                 rc = -ENOENT;
1767                 goto out_err_crypto_release;
1768 #endif
1769                 tcp_ses->smbd_conn = smbd_get_connection(
1770                         tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1771                 if (tcp_ses->smbd_conn) {
1772                         cifs_dbg(VFS, "RDMA transport established\n");
1773                         rc = 0;
1774                         goto smbd_connected;
1775                 } else {
1776                         rc = -ENOENT;
1777                         goto out_err_crypto_release;
1778                 }
1779         }
1780         rc = ip_connect(tcp_ses);
1781         if (rc < 0) {
1782                 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1783                 goto out_err_crypto_release;
1784         }
1785 smbd_connected:
1786         /*
1787          * since we're in a cifs function already, we know that
1788          * this will succeed. No need for try_module_get().
1789          */
1790         __module_get(THIS_MODULE);
1791         tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1792                                   tcp_ses, "cifsd");
1793         if (IS_ERR(tcp_ses->tsk)) {
1794                 rc = PTR_ERR(tcp_ses->tsk);
1795                 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1796                 module_put(THIS_MODULE);
1797                 goto out_err_crypto_release;
1798         }
1799         tcp_ses->min_offload = ctx->min_offload;
1800         /*
1801          * at this point we are the only ones with the pointer
1802          * to the struct since the kernel thread not created yet
1803          * no need to spinlock this update of tcpStatus
1804          */
1805         spin_lock(&tcp_ses->srv_lock);
1806         tcp_ses->tcpStatus = CifsNeedNegotiate;
1807         spin_unlock(&tcp_ses->srv_lock);
1808
1809         if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1810                 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1811         else
1812                 tcp_ses->max_credits = ctx->max_credits;
1813
1814         tcp_ses->nr_targets = 1;
1815         tcp_ses->ignore_signature = ctx->ignore_signature;
1816         /* thread spawned, put it on the list */
1817         spin_lock(&cifs_tcp_ses_lock);
1818         list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1819         spin_unlock(&cifs_tcp_ses_lock);
1820
1821         /* queue echo request delayed work */
1822         queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1823
1824         return tcp_ses;
1825
1826 out_err_crypto_release:
1827         cifs_crypto_secmech_release(tcp_ses);
1828
1829         put_net(cifs_net_ns(tcp_ses));
1830
1831 out_err:
1832         if (tcp_ses) {
1833                 if (SERVER_IS_CHAN(tcp_ses))
1834                         cifs_put_tcp_session(tcp_ses->primary_server, false);
1835                 kfree(tcp_ses->hostname);
1836                 kfree(tcp_ses->leaf_fullpath);
1837                 if (tcp_ses->ssocket)
1838                         sock_release(tcp_ses->ssocket);
1839                 kfree(tcp_ses);
1840         }
1841         return ERR_PTR(rc);
1842 }
1843
1844 /* this function must be called with ses_lock and chan_lock held */
1845 static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1846 {
1847         if (ctx->sectype != Unspecified &&
1848             ctx->sectype != ses->sectype)
1849                 return 0;
1850
1851         /*
1852          * If an existing session is limited to less channels than
1853          * requested, it should not be reused
1854          */
1855         if (ses->chan_max < ctx->max_channels)
1856                 return 0;
1857
1858         switch (ses->sectype) {
1859         case Kerberos:
1860                 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1861                         return 0;
1862                 break;
1863         default:
1864                 /* NULL username means anonymous session */
1865                 if (ses->user_name == NULL) {
1866                         if (!ctx->nullauth)
1867                                 return 0;
1868                         break;
1869                 }
1870
1871                 /* anything else takes username/password */
1872                 if (strncmp(ses->user_name,
1873                             ctx->username ? ctx->username : "",
1874                             CIFS_MAX_USERNAME_LEN))
1875                         return 0;
1876                 if ((ctx->username && strlen(ctx->username) != 0) &&
1877                     ses->password != NULL &&
1878                     strncmp(ses->password,
1879                             ctx->password ? ctx->password : "",
1880                             CIFS_MAX_PASSWORD_LEN))
1881                         return 0;
1882         }
1883
1884         if (strcmp(ctx->local_nls->charset, ses->local_nls->charset))
1885                 return 0;
1886
1887         return 1;
1888 }
1889
1890 /**
1891  * cifs_setup_ipc - helper to setup the IPC tcon for the session
1892  * @ses: smb session to issue the request on
1893  * @ctx: the superblock configuration context to use for building the
1894  *       new tree connection for the IPC (interprocess communication RPC)
1895  *
1896  * A new IPC connection is made and stored in the session
1897  * tcon_ipc. The IPC tcon has the same lifetime as the session.
1898  */
1899 static int
1900 cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1901 {
1902         int rc = 0, xid;
1903         struct cifs_tcon *tcon;
1904         char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1905         bool seal = false;
1906         struct TCP_Server_Info *server = ses->server;
1907
1908         /*
1909          * If the mount request that resulted in the creation of the
1910          * session requires encryption, force IPC to be encrypted too.
1911          */
1912         if (ctx->seal) {
1913                 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1914                         seal = true;
1915                 else {
1916                         cifs_server_dbg(VFS,
1917                                  "IPC: server doesn't support encryption\n");
1918                         return -EOPNOTSUPP;
1919                 }
1920         }
1921
1922         /* no need to setup directory caching on IPC share, so pass in false */
1923         tcon = tcon_info_alloc(false);
1924         if (tcon == NULL)
1925                 return -ENOMEM;
1926
1927         spin_lock(&server->srv_lock);
1928         scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1929         spin_unlock(&server->srv_lock);
1930
1931         xid = get_xid();
1932         tcon->ses = ses;
1933         tcon->ipc = true;
1934         tcon->seal = seal;
1935         rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1936         free_xid(xid);
1937
1938         if (rc) {
1939                 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1940                 tconInfoFree(tcon);
1941                 goto out;
1942         }
1943
1944         cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
1945
1946         spin_lock(&tcon->tc_lock);
1947         tcon->status = TID_GOOD;
1948         spin_unlock(&tcon->tc_lock);
1949         ses->tcon_ipc = tcon;
1950 out:
1951         return rc;
1952 }
1953
1954 /**
1955  * cifs_free_ipc - helper to release the session IPC tcon
1956  * @ses: smb session to unmount the IPC from
1957  *
1958  * Needs to be called everytime a session is destroyed.
1959  *
1960  * On session close, the IPC is closed and the server must release all tcons of the session.
1961  * No need to send a tree disconnect here.
1962  *
1963  * Besides, it will make the server to not close durable and resilient files on session close, as
1964  * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1965  */
1966 static int
1967 cifs_free_ipc(struct cifs_ses *ses)
1968 {
1969         struct cifs_tcon *tcon = ses->tcon_ipc;
1970
1971         if (tcon == NULL)
1972                 return 0;
1973
1974         tconInfoFree(tcon);
1975         ses->tcon_ipc = NULL;
1976         return 0;
1977 }
1978
1979 static struct cifs_ses *
1980 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1981 {
1982         struct cifs_ses *ses, *ret = NULL;
1983
1984         spin_lock(&cifs_tcp_ses_lock);
1985         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1986                 spin_lock(&ses->ses_lock);
1987                 if (ses->ses_status == SES_EXITING) {
1988                         spin_unlock(&ses->ses_lock);
1989                         continue;
1990                 }
1991                 spin_lock(&ses->chan_lock);
1992                 if (match_session(ses, ctx)) {
1993                         spin_unlock(&ses->chan_lock);
1994                         spin_unlock(&ses->ses_lock);
1995                         ret = ses;
1996                         break;
1997                 }
1998                 spin_unlock(&ses->chan_lock);
1999                 spin_unlock(&ses->ses_lock);
2000         }
2001         if (ret)
2002                 cifs_smb_ses_inc_refcount(ret);
2003         spin_unlock(&cifs_tcp_ses_lock);
2004         return ret;
2005 }
2006
2007 void __cifs_put_smb_ses(struct cifs_ses *ses)
2008 {
2009         struct TCP_Server_Info *server = ses->server;
2010         unsigned int xid;
2011         size_t i;
2012         int rc;
2013
2014         spin_lock(&ses->ses_lock);
2015         if (ses->ses_status == SES_EXITING) {
2016                 spin_unlock(&ses->ses_lock);
2017                 return;
2018         }
2019         spin_unlock(&ses->ses_lock);
2020
2021         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
2022         cifs_dbg(FYI,
2023                  "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
2024
2025         spin_lock(&cifs_tcp_ses_lock);
2026         if (--ses->ses_count > 0) {
2027                 spin_unlock(&cifs_tcp_ses_lock);
2028                 return;
2029         }
2030         spin_lock(&ses->ses_lock);
2031         if (ses->ses_status == SES_GOOD)
2032                 ses->ses_status = SES_EXITING;
2033         spin_unlock(&ses->ses_lock);
2034         spin_unlock(&cifs_tcp_ses_lock);
2035
2036         /* ses_count can never go negative */
2037         WARN_ON(ses->ses_count < 0);
2038
2039         spin_lock(&ses->ses_lock);
2040         if (ses->ses_status == SES_EXITING && server->ops->logoff) {
2041                 spin_unlock(&ses->ses_lock);
2042                 cifs_free_ipc(ses);
2043                 xid = get_xid();
2044                 rc = server->ops->logoff(xid, ses);
2045                 if (rc)
2046                         cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
2047                                 __func__, rc);
2048                 _free_xid(xid);
2049         } else {
2050                 spin_unlock(&ses->ses_lock);
2051                 cifs_free_ipc(ses);
2052         }
2053
2054         spin_lock(&cifs_tcp_ses_lock);
2055         list_del_init(&ses->smb_ses_list);
2056         spin_unlock(&cifs_tcp_ses_lock);
2057
2058         /* close any extra channels */
2059         for (i = 1; i < ses->chan_count; i++) {
2060                 if (ses->chans[i].iface) {
2061                         kref_put(&ses->chans[i].iface->refcount, release_iface);
2062                         ses->chans[i].iface = NULL;
2063                 }
2064                 cifs_put_tcp_session(ses->chans[i].server, 0);
2065                 ses->chans[i].server = NULL;
2066         }
2067
2068         sesInfoFree(ses);
2069         cifs_put_tcp_session(server, 0);
2070 }
2071
2072 #ifdef CONFIG_KEYS
2073
2074 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
2075 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
2076
2077 /* Populate username and pw fields from keyring if possible */
2078 static int
2079 cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
2080 {
2081         int rc = 0;
2082         int is_domain = 0;
2083         const char *delim, *payload;
2084         char *desc;
2085         ssize_t len;
2086         struct key *key;
2087         struct TCP_Server_Info *server = ses->server;
2088         struct sockaddr_in *sa;
2089         struct sockaddr_in6 *sa6;
2090         const struct user_key_payload *upayload;
2091
2092         desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
2093         if (!desc)
2094                 return -ENOMEM;
2095
2096         /* try to find an address key first */
2097         switch (server->dstaddr.ss_family) {
2098         case AF_INET:
2099                 sa = (struct sockaddr_in *)&server->dstaddr;
2100                 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
2101                 break;
2102         case AF_INET6:
2103                 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
2104                 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
2105                 break;
2106         default:
2107                 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
2108                          server->dstaddr.ss_family);
2109                 rc = -EINVAL;
2110                 goto out_err;
2111         }
2112
2113         cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2114         key = request_key(&key_type_logon, desc, "");
2115         if (IS_ERR(key)) {
2116                 if (!ses->domainName) {
2117                         cifs_dbg(FYI, "domainName is NULL\n");
2118                         rc = PTR_ERR(key);
2119                         goto out_err;
2120                 }
2121
2122                 /* didn't work, try to find a domain key */
2123                 sprintf(desc, "cifs:d:%s", ses->domainName);
2124                 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2125                 key = request_key(&key_type_logon, desc, "");
2126                 if (IS_ERR(key)) {
2127                         rc = PTR_ERR(key);
2128                         goto out_err;
2129                 }
2130                 is_domain = 1;
2131         }
2132
2133         down_read(&key->sem);
2134         upayload = user_key_payload_locked(key);
2135         if (IS_ERR_OR_NULL(upayload)) {
2136                 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
2137                 goto out_key_put;
2138         }
2139
2140         /* find first : in payload */
2141         payload = upayload->data;
2142         delim = strnchr(payload, upayload->datalen, ':');
2143         cifs_dbg(FYI, "payload=%s\n", payload);
2144         if (!delim) {
2145                 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
2146                          upayload->datalen);
2147                 rc = -EINVAL;
2148                 goto out_key_put;
2149         }
2150
2151         len = delim - payload;
2152         if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
2153                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
2154                          len);
2155                 rc = -EINVAL;
2156                 goto out_key_put;
2157         }
2158
2159         ctx->username = kstrndup(payload, len, GFP_KERNEL);
2160         if (!ctx->username) {
2161                 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
2162                          len);
2163                 rc = -ENOMEM;
2164                 goto out_key_put;
2165         }
2166         cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
2167
2168         len = key->datalen - (len + 1);
2169         if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
2170                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
2171                 rc = -EINVAL;
2172                 kfree(ctx->username);
2173                 ctx->username = NULL;
2174                 goto out_key_put;
2175         }
2176
2177         ++delim;
2178         ctx->password = kstrndup(delim, len, GFP_KERNEL);
2179         if (!ctx->password) {
2180                 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
2181                          len);
2182                 rc = -ENOMEM;
2183                 kfree(ctx->username);
2184                 ctx->username = NULL;
2185                 goto out_key_put;
2186         }
2187
2188         /*
2189          * If we have a domain key then we must set the domainName in the
2190          * for the request.
2191          */
2192         if (is_domain && ses->domainName) {
2193                 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
2194                 if (!ctx->domainname) {
2195                         cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
2196                                  len);
2197                         rc = -ENOMEM;
2198                         kfree(ctx->username);
2199                         ctx->username = NULL;
2200                         kfree_sensitive(ctx->password);
2201                         ctx->password = NULL;
2202                         goto out_key_put;
2203                 }
2204         }
2205
2206         strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
2207
2208 out_key_put:
2209         up_read(&key->sem);
2210         key_put(key);
2211 out_err:
2212         kfree(desc);
2213         cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
2214         return rc;
2215 }
2216 #else /* ! CONFIG_KEYS */
2217 static inline int
2218 cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
2219                    struct cifs_ses *ses __attribute__((unused)))
2220 {
2221         return -ENOSYS;
2222 }
2223 #endif /* CONFIG_KEYS */
2224
2225 /**
2226  * cifs_get_smb_ses - get a session matching @ctx data from @server
2227  * @server: server to setup the session to
2228  * @ctx: superblock configuration context to use to setup the session
2229  *
2230  * This function assumes it is being called from cifs_mount() where we
2231  * already got a server reference (server refcount +1). See
2232  * cifs_get_tcon() for refcount explanations.
2233  */
2234 struct cifs_ses *
2235 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
2236 {
2237         int rc = 0;
2238         unsigned int xid;
2239         struct cifs_ses *ses;
2240         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2241         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2242
2243         xid = get_xid();
2244
2245         ses = cifs_find_smb_ses(server, ctx);
2246         if (ses) {
2247                 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
2248                          ses->ses_status);
2249
2250                 spin_lock(&ses->chan_lock);
2251                 if (cifs_chan_needs_reconnect(ses, server)) {
2252                         spin_unlock(&ses->chan_lock);
2253                         cifs_dbg(FYI, "Session needs reconnect\n");
2254
2255                         mutex_lock(&ses->session_mutex);
2256                         rc = cifs_negotiate_protocol(xid, ses, server);
2257                         if (rc) {
2258                                 mutex_unlock(&ses->session_mutex);
2259                                 /* problem -- put our ses reference */
2260                                 cifs_put_smb_ses(ses);
2261                                 free_xid(xid);
2262                                 return ERR_PTR(rc);
2263                         }
2264
2265                         rc = cifs_setup_session(xid, ses, server,
2266                                                 ctx->local_nls);
2267                         if (rc) {
2268                                 mutex_unlock(&ses->session_mutex);
2269                                 /* problem -- put our reference */
2270                                 cifs_put_smb_ses(ses);
2271                                 free_xid(xid);
2272                                 return ERR_PTR(rc);
2273                         }
2274                         mutex_unlock(&ses->session_mutex);
2275
2276                         spin_lock(&ses->chan_lock);
2277                 }
2278                 spin_unlock(&ses->chan_lock);
2279
2280                 /* existing SMB ses has a server reference already */
2281                 cifs_put_tcp_session(server, 0);
2282                 free_xid(xid);
2283                 return ses;
2284         }
2285
2286         rc = -ENOMEM;
2287
2288         cifs_dbg(FYI, "Existing smb sess not found\n");
2289         ses = sesInfoAlloc();
2290         if (ses == NULL)
2291                 goto get_ses_fail;
2292
2293         /* new SMB session uses our server ref */
2294         ses->server = server;
2295         if (server->dstaddr.ss_family == AF_INET6)
2296                 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
2297         else
2298                 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
2299
2300         if (ctx->username) {
2301                 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
2302                 if (!ses->user_name)
2303                         goto get_ses_fail;
2304         }
2305
2306         /* ctx->password freed at unmount */
2307         if (ctx->password) {
2308                 ses->password = kstrdup(ctx->password, GFP_KERNEL);
2309                 if (!ses->password)
2310                         goto get_ses_fail;
2311         }
2312         if (ctx->domainname) {
2313                 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
2314                 if (!ses->domainName)
2315                         goto get_ses_fail;
2316         }
2317
2318         strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
2319
2320         if (ctx->domainauto)
2321                 ses->domainAuto = ctx->domainauto;
2322         ses->cred_uid = ctx->cred_uid;
2323         ses->linux_uid = ctx->linux_uid;
2324
2325         ses->sectype = ctx->sectype;
2326         ses->sign = ctx->sign;
2327         ses->local_nls = load_nls(ctx->local_nls->charset);
2328
2329         /* add server as first channel */
2330         spin_lock(&ses->chan_lock);
2331         ses->chans[0].server = server;
2332         ses->chan_count = 1;
2333         ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
2334         ses->chans_need_reconnect = 1;
2335         spin_unlock(&ses->chan_lock);
2336
2337         mutex_lock(&ses->session_mutex);
2338         rc = cifs_negotiate_protocol(xid, ses, server);
2339         if (!rc)
2340                 rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
2341         mutex_unlock(&ses->session_mutex);
2342
2343         /* each channel uses a different signing key */
2344         spin_lock(&ses->chan_lock);
2345         memcpy(ses->chans[0].signkey, ses->smb3signingkey,
2346                sizeof(ses->smb3signingkey));
2347         spin_unlock(&ses->chan_lock);
2348
2349         if (rc)
2350                 goto get_ses_fail;
2351
2352         /*
2353          * success, put it on the list and add it as first channel
2354          * note: the session becomes active soon after this. So you'll
2355          * need to lock before changing something in the session.
2356          */
2357         spin_lock(&cifs_tcp_ses_lock);
2358         ses->dfs_root_ses = ctx->dfs_root_ses;
2359         if (ses->dfs_root_ses)
2360                 ses->dfs_root_ses->ses_count++;
2361         list_add(&ses->smb_ses_list, &server->smb_ses_list);
2362         spin_unlock(&cifs_tcp_ses_lock);
2363
2364         cifs_setup_ipc(ses, ctx);
2365
2366         free_xid(xid);
2367
2368         return ses;
2369
2370 get_ses_fail:
2371         sesInfoFree(ses);
2372         free_xid(xid);
2373         return ERR_PTR(rc);
2374 }
2375
2376 /* this function must be called with tc_lock held */
2377 static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
2378 {
2379         struct TCP_Server_Info *server = tcon->ses->server;
2380
2381         if (tcon->status == TID_EXITING)
2382                 return 0;
2383
2384         if (tcon->origin_fullpath) {
2385                 if (!ctx->source ||
2386                     !dfs_src_pathname_equal(ctx->source,
2387                                             tcon->origin_fullpath))
2388                         return 0;
2389         } else if (!server->leaf_fullpath &&
2390                    strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE)) {
2391                 return 0;
2392         }
2393         if (tcon->seal != ctx->seal)
2394                 return 0;
2395         if (tcon->snapshot_time != ctx->snapshot_time)
2396                 return 0;
2397         if (tcon->handle_timeout != ctx->handle_timeout)
2398                 return 0;
2399         if (tcon->no_lease != ctx->no_lease)
2400                 return 0;
2401         if (tcon->nodelete != ctx->nodelete)
2402                 return 0;
2403         return 1;
2404 }
2405
2406 static struct cifs_tcon *
2407 cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2408 {
2409         struct cifs_tcon *tcon;
2410
2411         spin_lock(&cifs_tcp_ses_lock);
2412         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
2413                 spin_lock(&tcon->tc_lock);
2414                 if (!match_tcon(tcon, ctx)) {
2415                         spin_unlock(&tcon->tc_lock);
2416                         continue;
2417                 }
2418                 ++tcon->tc_count;
2419                 spin_unlock(&tcon->tc_lock);
2420                 spin_unlock(&cifs_tcp_ses_lock);
2421                 return tcon;
2422         }
2423         spin_unlock(&cifs_tcp_ses_lock);
2424         return NULL;
2425 }
2426
2427 void
2428 cifs_put_tcon(struct cifs_tcon *tcon)
2429 {
2430         unsigned int xid;
2431         struct cifs_ses *ses;
2432
2433         /*
2434          * IPC tcon share the lifetime of their session and are
2435          * destroyed in the session put function
2436          */
2437         if (tcon == NULL || tcon->ipc)
2438                 return;
2439
2440         ses = tcon->ses;
2441         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2442         spin_lock(&cifs_tcp_ses_lock);
2443         spin_lock(&tcon->tc_lock);
2444         if (--tcon->tc_count > 0) {
2445                 spin_unlock(&tcon->tc_lock);
2446                 spin_unlock(&cifs_tcp_ses_lock);
2447                 return;
2448         }
2449
2450         /* tc_count can never go negative */
2451         WARN_ON(tcon->tc_count < 0);
2452
2453         list_del_init(&tcon->tcon_list);
2454         tcon->status = TID_EXITING;
2455         spin_unlock(&tcon->tc_lock);
2456         spin_unlock(&cifs_tcp_ses_lock);
2457
2458         /* cancel polling of interfaces */
2459         cancel_delayed_work_sync(&tcon->query_interfaces);
2460 #ifdef CONFIG_CIFS_DFS_UPCALL
2461         cancel_delayed_work_sync(&tcon->dfs_cache_work);
2462 #endif
2463
2464         if (tcon->use_witness) {
2465                 int rc;
2466
2467                 rc = cifs_swn_unregister(tcon);
2468                 if (rc < 0) {
2469                         cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2470                                         __func__, rc);
2471                 }
2472         }
2473
2474         xid = get_xid();
2475         if (ses->server->ops->tree_disconnect)
2476                 ses->server->ops->tree_disconnect(xid, tcon);
2477         _free_xid(xid);
2478
2479         cifs_fscache_release_super_cookie(tcon);
2480         tconInfoFree(tcon);
2481         cifs_put_smb_ses(ses);
2482 }
2483
2484 /**
2485  * cifs_get_tcon - get a tcon matching @ctx data from @ses
2486  * @ses: smb session to issue the request on
2487  * @ctx: the superblock configuration context to use for building the
2488  *
2489  * - tcon refcount is the number of mount points using the tcon.
2490  * - ses refcount is the number of tcon using the session.
2491  *
2492  * 1. This function assumes it is being called from cifs_mount() where
2493  *    we already got a session reference (ses refcount +1).
2494  *
2495  * 2. Since we're in the context of adding a mount point, the end
2496  *    result should be either:
2497  *
2498  * a) a new tcon already allocated with refcount=1 (1 mount point) and
2499  *    its session refcount incremented (1 new tcon). This +1 was
2500  *    already done in (1).
2501  *
2502  * b) an existing tcon with refcount+1 (add a mount point to it) and
2503  *    identical ses refcount (no new tcon). Because of (1) we need to
2504  *    decrement the ses refcount.
2505  */
2506 static struct cifs_tcon *
2507 cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2508 {
2509         struct cifs_tcon *tcon;
2510         bool nohandlecache;
2511         int rc, xid;
2512
2513         tcon = cifs_find_tcon(ses, ctx);
2514         if (tcon) {
2515                 /*
2516                  * tcon has refcount already incremented but we need to
2517                  * decrement extra ses reference gotten by caller (case b)
2518                  */
2519                 cifs_dbg(FYI, "Found match on UNC path\n");
2520                 cifs_put_smb_ses(ses);
2521                 return tcon;
2522         }
2523
2524         if (!ses->server->ops->tree_connect) {
2525                 rc = -ENOSYS;
2526                 goto out_fail;
2527         }
2528
2529         if (ses->server->dialect >= SMB20_PROT_ID &&
2530             (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING))
2531                 nohandlecache = ctx->nohandlecache;
2532         else
2533                 nohandlecache = true;
2534         tcon = tcon_info_alloc(!nohandlecache);
2535         if (tcon == NULL) {
2536                 rc = -ENOMEM;
2537                 goto out_fail;
2538         }
2539         tcon->nohandlecache = nohandlecache;
2540
2541         if (ctx->snapshot_time) {
2542                 if (ses->server->vals->protocol_id == 0) {
2543                         cifs_dbg(VFS,
2544                              "Use SMB2 or later for snapshot mount option\n");
2545                         rc = -EOPNOTSUPP;
2546                         goto out_fail;
2547                 } else
2548                         tcon->snapshot_time = ctx->snapshot_time;
2549         }
2550
2551         if (ctx->handle_timeout) {
2552                 if (ses->server->vals->protocol_id == 0) {
2553                         cifs_dbg(VFS,
2554                              "Use SMB2.1 or later for handle timeout option\n");
2555                         rc = -EOPNOTSUPP;
2556                         goto out_fail;
2557                 } else
2558                         tcon->handle_timeout = ctx->handle_timeout;
2559         }
2560
2561         tcon->ses = ses;
2562         if (ctx->password) {
2563                 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2564                 if (!tcon->password) {
2565                         rc = -ENOMEM;
2566                         goto out_fail;
2567                 }
2568         }
2569
2570         if (ctx->seal) {
2571                 if (ses->server->vals->protocol_id == 0) {
2572                         cifs_dbg(VFS,
2573                                  "SMB3 or later required for encryption\n");
2574                         rc = -EOPNOTSUPP;
2575                         goto out_fail;
2576                 } else if (tcon->ses->server->capabilities &
2577                                         SMB2_GLOBAL_CAP_ENCRYPTION)
2578                         tcon->seal = true;
2579                 else {
2580                         cifs_dbg(VFS, "Encryption is not supported on share\n");
2581                         rc = -EOPNOTSUPP;
2582                         goto out_fail;
2583                 }
2584         }
2585
2586         if (ctx->linux_ext) {
2587                 if (ses->server->posix_ext_supported) {
2588                         tcon->posix_extensions = true;
2589                         pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2590                 } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
2591                     (strcmp(ses->server->vals->version_string,
2592                      SMB3ANY_VERSION_STRING) == 0) ||
2593                     (strcmp(ses->server->vals->version_string,
2594                      SMBDEFAULT_VERSION_STRING) == 0)) {
2595                         cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2596                         rc = -EOPNOTSUPP;
2597                         goto out_fail;
2598                 } else {
2599                         cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
2600                                 "disabled but required for POSIX extensions\n");
2601                         rc = -EOPNOTSUPP;
2602                         goto out_fail;
2603                 }
2604         }
2605
2606         xid = get_xid();
2607         rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2608                                             ctx->local_nls);
2609         free_xid(xid);
2610         cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2611         if (rc)
2612                 goto out_fail;
2613
2614         tcon->use_persistent = false;
2615         /* check if SMB2 or later, CIFS does not support persistent handles */
2616         if (ctx->persistent) {
2617                 if (ses->server->vals->protocol_id == 0) {
2618                         cifs_dbg(VFS,
2619                              "SMB3 or later required for persistent handles\n");
2620                         rc = -EOPNOTSUPP;
2621                         goto out_fail;
2622                 } else if (ses->server->capabilities &
2623                            SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2624                         tcon->use_persistent = true;
2625                 else /* persistent handles requested but not supported */ {
2626                         cifs_dbg(VFS,
2627                                 "Persistent handles not supported on share\n");
2628                         rc = -EOPNOTSUPP;
2629                         goto out_fail;
2630                 }
2631         } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2632              && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2633              && (ctx->nopersistent == false)) {
2634                 cifs_dbg(FYI, "enabling persistent handles\n");
2635                 tcon->use_persistent = true;
2636         } else if (ctx->resilient) {
2637                 if (ses->server->vals->protocol_id == 0) {
2638                         cifs_dbg(VFS,
2639                              "SMB2.1 or later required for resilient handles\n");
2640                         rc = -EOPNOTSUPP;
2641                         goto out_fail;
2642                 }
2643                 tcon->use_resilient = true;
2644         }
2645
2646         tcon->use_witness = false;
2647         if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2648                 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2649                         if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2650                                 /*
2651                                  * Set witness in use flag in first place
2652                                  * to retry registration in the echo task
2653                                  */
2654                                 tcon->use_witness = true;
2655                                 /* And try to register immediately */
2656                                 rc = cifs_swn_register(tcon);
2657                                 if (rc < 0) {
2658                                         cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2659                                         goto out_fail;
2660                                 }
2661                         } else {
2662                                 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2663                                 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2664                                 rc = -EOPNOTSUPP;
2665                                 goto out_fail;
2666                         }
2667                 } else {
2668                         cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2669                         rc = -EOPNOTSUPP;
2670                         goto out_fail;
2671                 }
2672         }
2673
2674         /* If the user really knows what they are doing they can override */
2675         if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2676                 if (ctx->cache_ro)
2677                         cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2678                 else if (ctx->cache_rw)
2679                         cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2680         }
2681
2682         if (ctx->no_lease) {
2683                 if (ses->server->vals->protocol_id == 0) {
2684                         cifs_dbg(VFS,
2685                                 "SMB2 or later required for nolease option\n");
2686                         rc = -EOPNOTSUPP;
2687                         goto out_fail;
2688                 } else
2689                         tcon->no_lease = ctx->no_lease;
2690         }
2691
2692         /*
2693          * We can have only one retry value for a connection to a share so for
2694          * resources mounted more than once to the same server share the last
2695          * value passed in for the retry flag is used.
2696          */
2697         tcon->retry = ctx->retry;
2698         tcon->nocase = ctx->nocase;
2699         tcon->broken_sparse_sup = ctx->no_sparse;
2700         tcon->max_cached_dirs = ctx->max_cached_dirs;
2701         tcon->nodelete = ctx->nodelete;
2702         tcon->local_lease = ctx->local_lease;
2703         INIT_LIST_HEAD(&tcon->pending_opens);
2704         tcon->status = TID_GOOD;
2705
2706         INIT_DELAYED_WORK(&tcon->query_interfaces,
2707                           smb2_query_server_interfaces);
2708         if (ses->server->dialect >= SMB30_PROT_ID &&
2709             (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
2710                 /* schedule query interfaces poll */
2711                 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
2712                                    (SMB_INTERFACE_POLL_INTERVAL * HZ));
2713         }
2714 #ifdef CONFIG_CIFS_DFS_UPCALL
2715         INIT_DELAYED_WORK(&tcon->dfs_cache_work, dfs_cache_refresh);
2716 #endif
2717         spin_lock(&cifs_tcp_ses_lock);
2718         list_add(&tcon->tcon_list, &ses->tcon_list);
2719         spin_unlock(&cifs_tcp_ses_lock);
2720
2721         return tcon;
2722
2723 out_fail:
2724         tconInfoFree(tcon);
2725         return ERR_PTR(rc);
2726 }
2727
2728 void
2729 cifs_put_tlink(struct tcon_link *tlink)
2730 {
2731         if (!tlink || IS_ERR(tlink))
2732                 return;
2733
2734         if (!atomic_dec_and_test(&tlink->tl_count) ||
2735             test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2736                 tlink->tl_time = jiffies;
2737                 return;
2738         }
2739
2740         if (!IS_ERR(tlink_tcon(tlink)))
2741                 cifs_put_tcon(tlink_tcon(tlink));
2742         kfree(tlink);
2743         return;
2744 }
2745
2746 static int
2747 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2748 {
2749         struct cifs_sb_info *old = CIFS_SB(sb);
2750         struct cifs_sb_info *new = mnt_data->cifs_sb;
2751         unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2752         unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2753
2754         if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2755                 return 0;
2756
2757         if (old->mnt_cifs_serverino_autodisabled)
2758                 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2759
2760         if (oldflags != newflags)
2761                 return 0;
2762
2763         /*
2764          * We want to share sb only if we don't specify an r/wsize or
2765          * specified r/wsize is greater than or equal to existing one.
2766          */
2767         if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2768                 return 0;
2769
2770         if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2771                 return 0;
2772
2773         if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2774             !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2775                 return 0;
2776
2777         if (old->ctx->file_mode != new->ctx->file_mode ||
2778             old->ctx->dir_mode != new->ctx->dir_mode)
2779                 return 0;
2780
2781         if (strcmp(old->local_nls->charset, new->local_nls->charset))
2782                 return 0;
2783
2784         if (old->ctx->acregmax != new->ctx->acregmax)
2785                 return 0;
2786         if (old->ctx->acdirmax != new->ctx->acdirmax)
2787                 return 0;
2788         if (old->ctx->closetimeo != new->ctx->closetimeo)
2789                 return 0;
2790
2791         return 1;
2792 }
2793
2794 static int match_prepath(struct super_block *sb,
2795                          struct cifs_tcon *tcon,
2796                          struct cifs_mnt_data *mnt_data)
2797 {
2798         struct smb3_fs_context *ctx = mnt_data->ctx;
2799         struct cifs_sb_info *old = CIFS_SB(sb);
2800         struct cifs_sb_info *new = mnt_data->cifs_sb;
2801         bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2802                 old->prepath;
2803         bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2804                 new->prepath;
2805
2806         if (tcon->origin_fullpath &&
2807             dfs_src_pathname_equal(tcon->origin_fullpath, ctx->source))
2808                 return 1;
2809
2810         if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2811                 return 1;
2812         else if (!old_set && !new_set)
2813                 return 1;
2814
2815         return 0;
2816 }
2817
2818 int
2819 cifs_match_super(struct super_block *sb, void *data)
2820 {
2821         struct cifs_mnt_data *mnt_data = data;
2822         struct smb3_fs_context *ctx;
2823         struct cifs_sb_info *cifs_sb;
2824         struct TCP_Server_Info *tcp_srv;
2825         struct cifs_ses *ses;
2826         struct cifs_tcon *tcon;
2827         struct tcon_link *tlink;
2828         int rc = 0;
2829
2830         spin_lock(&cifs_tcp_ses_lock);
2831         cifs_sb = CIFS_SB(sb);
2832
2833         /* We do not want to use a superblock that has been shutdown */
2834         if (CIFS_MOUNT_SHUTDOWN & cifs_sb->mnt_cifs_flags) {
2835                 spin_unlock(&cifs_tcp_ses_lock);
2836                 return 0;
2837         }
2838
2839         tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2840         if (IS_ERR_OR_NULL(tlink)) {
2841                 pr_warn_once("%s: skip super matching due to bad tlink(%p)\n",
2842                              __func__, tlink);
2843                 spin_unlock(&cifs_tcp_ses_lock);
2844                 return 0;
2845         }
2846         tcon = tlink_tcon(tlink);
2847         ses = tcon->ses;
2848         tcp_srv = ses->server;
2849
2850         ctx = mnt_data->ctx;
2851
2852         spin_lock(&tcp_srv->srv_lock);
2853         spin_lock(&ses->ses_lock);
2854         spin_lock(&ses->chan_lock);
2855         spin_lock(&tcon->tc_lock);
2856         if (!match_server(tcp_srv, ctx, true) ||
2857             !match_session(ses, ctx) ||
2858             !match_tcon(tcon, ctx) ||
2859             !match_prepath(sb, tcon, mnt_data)) {
2860                 rc = 0;
2861                 goto out;
2862         }
2863
2864         rc = compare_mount_options(sb, mnt_data);
2865 out:
2866         spin_unlock(&tcon->tc_lock);
2867         spin_unlock(&ses->chan_lock);
2868         spin_unlock(&ses->ses_lock);
2869         spin_unlock(&tcp_srv->srv_lock);
2870
2871         spin_unlock(&cifs_tcp_ses_lock);
2872         cifs_put_tlink(tlink);
2873         return rc;
2874 }
2875
2876 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2877 static struct lock_class_key cifs_key[2];
2878 static struct lock_class_key cifs_slock_key[2];
2879
2880 static inline void
2881 cifs_reclassify_socket4(struct socket *sock)
2882 {
2883         struct sock *sk = sock->sk;
2884         BUG_ON(!sock_allow_reclassification(sk));
2885         sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2886                 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2887 }
2888
2889 static inline void
2890 cifs_reclassify_socket6(struct socket *sock)
2891 {
2892         struct sock *sk = sock->sk;
2893         BUG_ON(!sock_allow_reclassification(sk));
2894         sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2895                 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2896 }
2897 #else
2898 static inline void
2899 cifs_reclassify_socket4(struct socket *sock)
2900 {
2901 }
2902
2903 static inline void
2904 cifs_reclassify_socket6(struct socket *sock)
2905 {
2906 }
2907 #endif
2908
2909 /* See RFC1001 section 14 on representation of Netbios names */
2910 static void rfc1002mangle(char *target, char *source, unsigned int length)
2911 {
2912         unsigned int i, j;
2913
2914         for (i = 0, j = 0; i < (length); i++) {
2915                 /* mask a nibble at a time and encode */
2916                 target[j] = 'A' + (0x0F & (source[i] >> 4));
2917                 target[j+1] = 'A' + (0x0F & source[i]);
2918                 j += 2;
2919         }
2920
2921 }
2922
2923 static int
2924 bind_socket(struct TCP_Server_Info *server)
2925 {
2926         int rc = 0;
2927         if (server->srcaddr.ss_family != AF_UNSPEC) {
2928                 /* Bind to the specified local IP address */
2929                 struct socket *socket = server->ssocket;
2930                 rc = kernel_bind(socket,
2931                                  (struct sockaddr *) &server->srcaddr,
2932                                  sizeof(server->srcaddr));
2933                 if (rc < 0) {
2934                         struct sockaddr_in *saddr4;
2935                         struct sockaddr_in6 *saddr6;
2936                         saddr4 = (struct sockaddr_in *)&server->srcaddr;
2937                         saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2938                         if (saddr6->sin6_family == AF_INET6)
2939                                 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2940                                          &saddr6->sin6_addr, rc);
2941                         else
2942                                 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2943                                          &saddr4->sin_addr.s_addr, rc);
2944                 }
2945         }
2946         return rc;
2947 }
2948
2949 static int
2950 ip_rfc1001_connect(struct TCP_Server_Info *server)
2951 {
2952         int rc = 0;
2953         /*
2954          * some servers require RFC1001 sessinit before sending
2955          * negprot - BB check reconnection in case where second
2956          * sessinit is sent but no second negprot
2957          */
2958         struct rfc1002_session_packet req = {};
2959         struct smb_hdr *smb_buf = (struct smb_hdr *)&req;
2960         unsigned int len;
2961
2962         req.trailer.session_req.called_len = sizeof(req.trailer.session_req.called_name);
2963
2964         if (server->server_RFC1001_name[0] != 0)
2965                 rfc1002mangle(req.trailer.session_req.called_name,
2966                               server->server_RFC1001_name,
2967                               RFC1001_NAME_LEN_WITH_NULL);
2968         else
2969                 rfc1002mangle(req.trailer.session_req.called_name,
2970                               DEFAULT_CIFS_CALLED_NAME,
2971                               RFC1001_NAME_LEN_WITH_NULL);
2972
2973         req.trailer.session_req.calling_len = sizeof(req.trailer.session_req.calling_name);
2974
2975         /* calling name ends in null (byte 16) from old smb convention */
2976         if (server->workstation_RFC1001_name[0] != 0)
2977                 rfc1002mangle(req.trailer.session_req.calling_name,
2978                               server->workstation_RFC1001_name,
2979                               RFC1001_NAME_LEN_WITH_NULL);
2980         else
2981                 rfc1002mangle(req.trailer.session_req.calling_name,
2982                               "LINUX_CIFS_CLNT",
2983                               RFC1001_NAME_LEN_WITH_NULL);
2984
2985         /*
2986          * As per rfc1002, @len must be the number of bytes that follows the
2987          * length field of a rfc1002 session request payload.
2988          */
2989         len = sizeof(req) - offsetof(struct rfc1002_session_packet, trailer.session_req);
2990
2991         smb_buf->smb_buf_length = cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | len);
2992         rc = smb_send(server, smb_buf, len);
2993         /*
2994          * RFC1001 layer in at least one server requires very short break before
2995          * negprot presumably because not expecting negprot to follow so fast.
2996          * This is a simple solution that works without complicating the code
2997          * and causes no significant slowing down on mount for everyone else
2998          */
2999         usleep_range(1000, 2000);
3000
3001         return rc;
3002 }
3003
3004 static int
3005 generic_ip_connect(struct TCP_Server_Info *server)
3006 {
3007         struct sockaddr *saddr;
3008         struct socket *socket;
3009         int slen, sfamily;
3010         __be16 sport;
3011         int rc = 0;
3012
3013         saddr = (struct sockaddr *) &server->dstaddr;
3014
3015         if (server->dstaddr.ss_family == AF_INET6) {
3016                 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
3017
3018                 sport = ipv6->sin6_port;
3019                 slen = sizeof(struct sockaddr_in6);
3020                 sfamily = AF_INET6;
3021                 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
3022                                 ntohs(sport));
3023         } else {
3024                 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
3025
3026                 sport = ipv4->sin_port;
3027                 slen = sizeof(struct sockaddr_in);
3028                 sfamily = AF_INET;
3029                 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
3030                                 ntohs(sport));
3031         }
3032
3033         if (server->ssocket) {
3034                 socket = server->ssocket;
3035         } else {
3036                 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
3037                                    IPPROTO_TCP, &server->ssocket, 1);
3038                 if (rc < 0) {
3039                         cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
3040                         return rc;
3041                 }
3042
3043                 /* BB other socket options to set KEEPALIVE, NODELAY? */
3044                 cifs_dbg(FYI, "Socket created\n");
3045                 socket = server->ssocket;
3046                 socket->sk->sk_allocation = GFP_NOFS;
3047                 socket->sk->sk_use_task_frag = false;
3048                 if (sfamily == AF_INET6)
3049                         cifs_reclassify_socket6(socket);
3050                 else
3051                         cifs_reclassify_socket4(socket);
3052         }
3053
3054         rc = bind_socket(server);
3055         if (rc < 0)
3056                 return rc;
3057
3058         /*
3059          * Eventually check for other socket options to change from
3060          * the default. sock_setsockopt not used because it expects
3061          * user space buffer
3062          */
3063         socket->sk->sk_rcvtimeo = 7 * HZ;
3064         socket->sk->sk_sndtimeo = 5 * HZ;
3065
3066         /* make the bufsizes depend on wsize/rsize and max requests */
3067         if (server->noautotune) {
3068                 if (socket->sk->sk_sndbuf < (200 * 1024))
3069                         socket->sk->sk_sndbuf = 200 * 1024;
3070                 if (socket->sk->sk_rcvbuf < (140 * 1024))
3071                         socket->sk->sk_rcvbuf = 140 * 1024;
3072         }
3073
3074         if (server->tcp_nodelay)
3075                 tcp_sock_set_nodelay(socket->sk);
3076
3077         cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
3078                  socket->sk->sk_sndbuf,
3079                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
3080
3081         rc = kernel_connect(socket, saddr, slen,
3082                             server->noblockcnt ? O_NONBLOCK : 0);
3083         /*
3084          * When mounting SMB root file systems, we do not want to block in
3085          * connect. Otherwise bail out and then let cifs_reconnect() perform
3086          * reconnect failover - if possible.
3087          */
3088         if (server->noblockcnt && rc == -EINPROGRESS)
3089                 rc = 0;
3090         if (rc < 0) {
3091                 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3092                 trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
3093                 sock_release(socket);
3094                 server->ssocket = NULL;
3095                 return rc;
3096         }
3097         trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
3098         if (sport == htons(RFC1001_PORT))
3099                 rc = ip_rfc1001_connect(server);
3100
3101         return rc;
3102 }
3103
3104 static int
3105 ip_connect(struct TCP_Server_Info *server)
3106 {
3107         __be16 *sport;
3108         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3109         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3110
3111         if (server->dstaddr.ss_family == AF_INET6)
3112                 sport = &addr6->sin6_port;
3113         else
3114                 sport = &addr->sin_port;
3115
3116         if (*sport == 0) {
3117                 int rc;
3118
3119                 /* try with 445 port at first */
3120                 *sport = htons(CIFS_PORT);
3121
3122                 rc = generic_ip_connect(server);
3123                 if (rc >= 0)
3124                         return rc;
3125
3126                 /* if it failed, try with 139 port */
3127                 *sport = htons(RFC1001_PORT);
3128         }
3129
3130         return generic_ip_connect(server);
3131 }
3132
3133 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3134 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3135                           struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3136 {
3137         /*
3138          * If we are reconnecting then should we check to see if
3139          * any requested capabilities changed locally e.g. via
3140          * remount but we can not do much about it here
3141          * if they have (even if we could detect it by the following)
3142          * Perhaps we could add a backpointer to array of sb from tcon
3143          * or if we change to make all sb to same share the same
3144          * sb as NFS - then we only have one backpointer to sb.
3145          * What if we wanted to mount the server share twice once with
3146          * and once without posixacls or posix paths?
3147          */
3148         __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3149
3150         if (ctx && ctx->no_linux_ext) {
3151                 tcon->fsUnixInfo.Capability = 0;
3152                 tcon->unix_ext = 0; /* Unix Extensions disabled */
3153                 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
3154                 return;
3155         } else if (ctx)
3156                 tcon->unix_ext = 1; /* Unix Extensions supported */
3157
3158         if (!tcon->unix_ext) {
3159                 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
3160                 return;
3161         }
3162
3163         if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
3164                 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3165                 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
3166                 /*
3167                  * check for reconnect case in which we do not
3168                  * want to change the mount behavior if we can avoid it
3169                  */
3170                 if (ctx == NULL) {
3171                         /*
3172                          * turn off POSIX ACL and PATHNAMES if not set
3173                          * originally at mount time
3174                          */
3175                         if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
3176                                 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3177                         if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3178                                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3179                                         cifs_dbg(VFS, "POSIXPATH support change\n");
3180                                 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3181                         } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3182                                 cifs_dbg(VFS, "possible reconnect error\n");
3183                                 cifs_dbg(VFS, "server disabled POSIX path support\n");
3184                         }
3185                 }
3186
3187                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3188                         cifs_dbg(VFS, "per-share encryption not supported yet\n");
3189
3190                 cap &= CIFS_UNIX_CAP_MASK;
3191                 if (ctx && ctx->no_psx_acl)
3192                         cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3193                 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
3194                         cifs_dbg(FYI, "negotiated posix acl support\n");
3195                         if (cifs_sb)
3196                                 cifs_sb->mnt_cifs_flags |=
3197                                         CIFS_MOUNT_POSIXACL;
3198                 }
3199
3200                 if (ctx && ctx->posix_paths == 0)
3201                         cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3202                 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
3203                         cifs_dbg(FYI, "negotiate posix pathnames\n");
3204                         if (cifs_sb)
3205                                 cifs_sb->mnt_cifs_flags |=
3206                                         CIFS_MOUNT_POSIX_PATHS;
3207                 }
3208
3209                 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
3210 #ifdef CONFIG_CIFS_DEBUG2
3211                 if (cap & CIFS_UNIX_FCNTL_CAP)
3212                         cifs_dbg(FYI, "FCNTL cap\n");
3213                 if (cap & CIFS_UNIX_EXTATTR_CAP)
3214                         cifs_dbg(FYI, "EXTATTR cap\n");
3215                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3216                         cifs_dbg(FYI, "POSIX path cap\n");
3217                 if (cap & CIFS_UNIX_XATTR_CAP)
3218                         cifs_dbg(FYI, "XATTR cap\n");
3219                 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
3220                         cifs_dbg(FYI, "POSIX ACL cap\n");
3221                 if (cap & CIFS_UNIX_LARGE_READ_CAP)
3222                         cifs_dbg(FYI, "very large read cap\n");
3223                 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
3224                         cifs_dbg(FYI, "very large write cap\n");
3225                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
3226                         cifs_dbg(FYI, "transport encryption cap\n");
3227                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3228                         cifs_dbg(FYI, "mandatory transport encryption cap\n");
3229 #endif /* CIFS_DEBUG2 */
3230                 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
3231                         if (ctx == NULL)
3232                                 cifs_dbg(FYI, "resetting capabilities failed\n");
3233                         else
3234                                 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");
3235
3236                 }
3237         }
3238 }
3239 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3240
3241 int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
3242 {
3243         struct smb3_fs_context *ctx = cifs_sb->ctx;
3244
3245         INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
3246
3247         spin_lock_init(&cifs_sb->tlink_tree_lock);
3248         cifs_sb->tlink_tree = RB_ROOT;
3249
3250         cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
3251                  ctx->file_mode, ctx->dir_mode);
3252
3253         /* this is needed for ASCII cp to Unicode converts */
3254         if (ctx->iocharset == NULL) {
3255                 /* load_nls_default cannot return null */
3256                 cifs_sb->local_nls = load_nls_default();
3257         } else {
3258                 cifs_sb->local_nls = load_nls(ctx->iocharset);
3259                 if (cifs_sb->local_nls == NULL) {
3260                         cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
3261                                  ctx->iocharset);
3262                         return -ELIBACC;
3263                 }
3264         }
3265         ctx->local_nls = cifs_sb->local_nls;
3266
3267         smb3_update_mnt_flags(cifs_sb);
3268
3269         if (ctx->direct_io)
3270                 cifs_dbg(FYI, "mounting share using direct i/o\n");
3271         if (ctx->cache_ro) {
3272                 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
3273                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
3274         } else if (ctx->cache_rw) {
3275                 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
3276                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
3277                                             CIFS_MOUNT_RW_CACHE);
3278         }
3279
3280         if ((ctx->cifs_acl) && (ctx->dynperm))
3281                 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
3282
3283         if (ctx->prepath) {
3284                 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
3285                 if (cifs_sb->prepath == NULL)
3286                         return -ENOMEM;
3287                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3288         }
3289
3290         return 0;
3291 }
3292
3293 /* Release all succeed connections */
3294 void cifs_mount_put_conns(struct cifs_mount_ctx *mnt_ctx)
3295 {
3296         int rc = 0;
3297
3298         if (mnt_ctx->tcon)
3299                 cifs_put_tcon(mnt_ctx->tcon);
3300         else if (mnt_ctx->ses)
3301                 cifs_put_smb_ses(mnt_ctx->ses);
3302         else if (mnt_ctx->server)
3303                 cifs_put_tcp_session(mnt_ctx->server, 0);
3304         mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
3305         free_xid(mnt_ctx->xid);
3306 }
3307
3308 int cifs_mount_get_session(struct cifs_mount_ctx *mnt_ctx)
3309 {
3310         struct TCP_Server_Info *server = NULL;
3311         struct smb3_fs_context *ctx;
3312         struct cifs_ses *ses = NULL;
3313         unsigned int xid;
3314         int rc = 0;
3315
3316         xid = get_xid();
3317
3318         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->fs_ctx)) {
3319                 rc = -EINVAL;
3320                 goto out;
3321         }
3322         ctx = mnt_ctx->fs_ctx;
3323
3324         /* get a reference to a tcp session */
3325         server = cifs_get_tcp_session(ctx, NULL);
3326         if (IS_ERR(server)) {
3327                 rc = PTR_ERR(server);
3328                 server = NULL;
3329                 goto out;
3330         }
3331
3332         /* get a reference to a SMB session */
3333         ses = cifs_get_smb_ses(server, ctx);
3334         if (IS_ERR(ses)) {
3335                 rc = PTR_ERR(ses);
3336                 ses = NULL;
3337                 goto out;
3338         }
3339
3340         if ((ctx->persistent == true) && (!(ses->server->capabilities &
3341                                             SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
3342                 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
3343                 rc = -EOPNOTSUPP;
3344         }
3345
3346 out:
3347         mnt_ctx->xid = xid;
3348         mnt_ctx->server = server;
3349         mnt_ctx->ses = ses;
3350         mnt_ctx->tcon = NULL;
3351
3352         return rc;
3353 }
3354
3355 int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx)
3356 {
3357         struct TCP_Server_Info *server;
3358         struct cifs_sb_info *cifs_sb;
3359         struct smb3_fs_context *ctx;
3360         struct cifs_tcon *tcon = NULL;
3361         int rc = 0;
3362
3363         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->server || !mnt_ctx->ses || !mnt_ctx->fs_ctx ||
3364                          !mnt_ctx->cifs_sb)) {
3365                 rc = -EINVAL;
3366                 goto out;
3367         }
3368         server = mnt_ctx->server;
3369         ctx = mnt_ctx->fs_ctx;
3370         cifs_sb = mnt_ctx->cifs_sb;
3371
3372         /* search for existing tcon to this server share */
3373         tcon = cifs_get_tcon(mnt_ctx->ses, ctx);
3374         if (IS_ERR(tcon)) {
3375                 rc = PTR_ERR(tcon);
3376                 tcon = NULL;
3377                 goto out;
3378         }
3379
3380         /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
3381         if (tcon->posix_extensions)
3382                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
3383
3384 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3385         /* tell server which Unix caps we support */
3386         if (cap_unix(tcon->ses)) {
3387                 /*
3388                  * reset of caps checks mount to see if unix extensions disabled
3389                  * for just this mount.
3390                  */
3391                 reset_cifs_unix_caps(mnt_ctx->xid, tcon, cifs_sb, ctx);
3392                 spin_lock(&tcon->ses->server->srv_lock);
3393                 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
3394                     (le64_to_cpu(tcon->fsUnixInfo.Capability) &
3395                      CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
3396                         spin_unlock(&tcon->ses->server->srv_lock);
3397                         rc = -EACCES;
3398                         goto out;
3399                 }
3400                 spin_unlock(&tcon->ses->server->srv_lock);
3401         } else
3402 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3403                 tcon->unix_ext = 0; /* server does not support them */
3404
3405         /* do not care if a following call succeed - informational */
3406         if (!tcon->pipe && server->ops->qfs_tcon) {
3407                 server->ops->qfs_tcon(mnt_ctx->xid, tcon, cifs_sb);
3408                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
3409                         if (tcon->fsDevInfo.DeviceCharacteristics &
3410                             cpu_to_le32(FILE_READ_ONLY_DEVICE))
3411                                 cifs_dbg(VFS, "mounted to read only share\n");
3412                         else if ((cifs_sb->mnt_cifs_flags &
3413                                   CIFS_MOUNT_RW_CACHE) == 0)
3414                                 cifs_dbg(VFS, "read only mount of RW share\n");
3415                         /* no need to log a RW mount of a typical RW share */
3416                 }
3417         }
3418
3419         /*
3420          * Clamp the rsize/wsize mount arguments if they are too big for the server
3421          * and set the rsize/wsize to the negotiated values if not passed in by
3422          * the user on mount
3423          */
3424         if ((cifs_sb->ctx->wsize == 0) ||
3425             (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
3426                 cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
3427         if ((cifs_sb->ctx->rsize == 0) ||
3428             (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
3429                 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
3430
3431         /*
3432          * The cookie is initialized from volume info returned above.
3433          * Inside cifs_fscache_get_super_cookie it checks
3434          * that we do not get super cookie twice.
3435          */
3436         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
3437                 cifs_fscache_get_super_cookie(tcon);
3438
3439 out:
3440         mnt_ctx->tcon = tcon;
3441         return rc;
3442 }
3443
3444 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
3445                              struct cifs_tcon *tcon)
3446 {
3447         struct tcon_link *tlink;
3448
3449         /* hang the tcon off of the superblock */
3450         tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
3451         if (tlink == NULL)
3452                 return -ENOMEM;
3453
3454         tlink->tl_uid = ses->linux_uid;
3455         tlink->tl_tcon = tcon;
3456         tlink->tl_time = jiffies;
3457         set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
3458         set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3459
3460         cifs_sb->master_tlink = tlink;
3461         spin_lock(&cifs_sb->tlink_tree_lock);
3462         tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
3463         spin_unlock(&cifs_sb->tlink_tree_lock);
3464
3465         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
3466                                 TLINK_IDLE_EXPIRE);
3467         return 0;
3468 }
3469
3470 static int
3471 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3472                                         unsigned int xid,
3473                                         struct cifs_tcon *tcon,
3474                                         struct cifs_sb_info *cifs_sb,
3475                                         char *full_path,
3476                                         int added_treename)
3477 {
3478         int rc;
3479         char *s;
3480         char sep, tmp;
3481         int skip = added_treename ? 1 : 0;
3482
3483         sep = CIFS_DIR_SEP(cifs_sb);
3484         s = full_path;
3485
3486         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3487         while (rc == 0) {
3488                 /* skip separators */
3489                 while (*s == sep)
3490                         s++;
3491                 if (!*s)
3492                         break;
3493                 /* next separator */
3494                 while (*s && *s != sep)
3495                         s++;
3496                 /*
3497                  * if the treename is added, we then have to skip the first
3498                  * part within the separators
3499                  */
3500                 if (skip) {
3501                         skip = 0;
3502                         continue;
3503                 }
3504                 /*
3505                  * temporarily null-terminate the path at the end of
3506                  * the current component
3507                  */
3508                 tmp = *s;
3509                 *s = 0;
3510                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3511                                                      full_path);
3512                 *s = tmp;
3513         }
3514         return rc;
3515 }
3516
3517 /*
3518  * Check if path is remote (i.e. a DFS share).
3519  *
3520  * Return -EREMOTE if it is, otherwise 0 or -errno.
3521  */
3522 int cifs_is_path_remote(struct cifs_mount_ctx *mnt_ctx)
3523 {
3524         int rc;
3525         struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
3526         struct TCP_Server_Info *server = mnt_ctx->server;
3527         unsigned int xid = mnt_ctx->xid;
3528         struct cifs_tcon *tcon = mnt_ctx->tcon;
3529         struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
3530         char *full_path;
3531
3532         if (!server->ops->is_path_accessible)
3533                 return -EOPNOTSUPP;
3534
3535         /*
3536          * cifs_build_path_to_root works only when we have a valid tcon
3537          */
3538         full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3539                                             tcon->Flags & SMB_SHARE_IS_IN_DFS);
3540         if (full_path == NULL)
3541                 return -ENOMEM;
3542
3543         cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3544
3545         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3546                                              full_path);
3547         if (rc != 0 && rc != -EREMOTE)
3548                 goto out;
3549
3550         if (rc != -EREMOTE) {
3551                 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3552                         cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3553                 if (rc != 0) {
3554                         cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3555                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3556                         rc = 0;
3557                 }
3558         }
3559
3560 out:
3561         kfree(full_path);
3562         return rc;
3563 }
3564
3565 #ifdef CONFIG_CIFS_DFS_UPCALL
3566 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3567 {
3568         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3569         bool isdfs;
3570         int rc;
3571
3572         INIT_LIST_HEAD(&mnt_ctx.dfs_ses_list);
3573
3574         rc = dfs_mount_share(&mnt_ctx, &isdfs);
3575         if (rc)
3576                 goto error;
3577         if (!isdfs)
3578                 goto out;
3579
3580         /*
3581          * After reconnecting to a different server, unique ids won't match anymore, so we disable
3582          * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
3583          */
3584         cifs_autodisable_serverino(cifs_sb);
3585         /*
3586          * Force the use of prefix path to support failover on DFS paths that resolve to targets
3587          * that have different prefix paths.
3588          */
3589         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3590         kfree(cifs_sb->prepath);
3591         cifs_sb->prepath = ctx->prepath;
3592         ctx->prepath = NULL;
3593
3594 out:
3595         cifs_try_adding_channels(mnt_ctx.ses);
3596         rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3597         if (rc)
3598                 goto error;
3599
3600         free_xid(mnt_ctx.xid);
3601         return rc;
3602
3603 error:
3604         dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
3605         cifs_mount_put_conns(&mnt_ctx);
3606         return rc;
3607 }
3608 #else
3609 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3610 {
3611         int rc = 0;
3612         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3613
3614         rc = cifs_mount_get_session(&mnt_ctx);
3615         if (rc)
3616                 goto error;
3617
3618         rc = cifs_mount_get_tcon(&mnt_ctx);
3619         if (rc)
3620                 goto error;
3621
3622         rc = cifs_is_path_remote(&mnt_ctx);
3623         if (rc == -EREMOTE)
3624                 rc = -EOPNOTSUPP;
3625         if (rc)
3626                 goto error;
3627
3628         rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3629         if (rc)
3630                 goto error;
3631
3632         free_xid(mnt_ctx.xid);
3633         return rc;
3634
3635 error:
3636         cifs_mount_put_conns(&mnt_ctx);
3637         return rc;
3638 }
3639 #endif
3640
3641 /*
3642  * Issue a TREE_CONNECT request.
3643  */
3644 int
3645 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3646          const char *tree, struct cifs_tcon *tcon,
3647          const struct nls_table *nls_codepage)
3648 {
3649         struct smb_hdr *smb_buffer;
3650         struct smb_hdr *smb_buffer_response;
3651         TCONX_REQ *pSMB;
3652         TCONX_RSP *pSMBr;
3653         unsigned char *bcc_ptr;
3654         int rc = 0;
3655         int length;
3656         __u16 bytes_left, count;
3657
3658         if (ses == NULL)
3659                 return -EIO;
3660
3661         smb_buffer = cifs_buf_get();
3662         if (smb_buffer == NULL)
3663                 return -ENOMEM;
3664
3665         smb_buffer_response = smb_buffer;
3666
3667         header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3668                         NULL /*no tid */ , 4 /*wct */ );
3669
3670         smb_buffer->Mid = get_next_mid(ses->server);
3671         smb_buffer->Uid = ses->Suid;
3672         pSMB = (TCONX_REQ *) smb_buffer;
3673         pSMBr = (TCONX_RSP *) smb_buffer_response;
3674
3675         pSMB->AndXCommand = 0xFF;
3676         pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3677         bcc_ptr = &pSMB->Password[0];
3678
3679         pSMB->PasswordLength = cpu_to_le16(1);  /* minimum */
3680         *bcc_ptr = 0; /* password is null byte */
3681         bcc_ptr++;              /* skip password */
3682         /* already aligned so no need to do it below */
3683
3684         if (ses->server->sign)
3685                 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3686
3687         if (ses->capabilities & CAP_STATUS32) {
3688                 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3689         }
3690         if (ses->capabilities & CAP_DFS) {
3691                 smb_buffer->Flags2 |= SMBFLG2_DFS;
3692         }
3693         if (ses->capabilities & CAP_UNICODE) {
3694                 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3695                 length =
3696                     cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3697                         6 /* max utf8 char length in bytes */ *
3698                         (/* server len*/ + 256 /* share len */), nls_codepage);
3699                 bcc_ptr += 2 * length;  /* convert num 16 bit words to bytes */
3700                 bcc_ptr += 2;   /* skip trailing null */
3701         } else {                /* ASCII */
3702                 strcpy(bcc_ptr, tree);
3703                 bcc_ptr += strlen(tree) + 1;
3704         }
3705         strcpy(bcc_ptr, "?????");
3706         bcc_ptr += strlen("?????");
3707         bcc_ptr += 1;
3708         count = bcc_ptr - &pSMB->Password[0];
3709         be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3710         pSMB->ByteCount = cpu_to_le16(count);
3711
3712         rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3713                          0);
3714
3715         /* above now done in SendReceive */
3716         if (rc == 0) {
3717                 bool is_unicode;
3718
3719                 tcon->tid = smb_buffer_response->Tid;
3720                 bcc_ptr = pByteArea(smb_buffer_response);
3721                 bytes_left = get_bcc(smb_buffer_response);
3722                 length = strnlen(bcc_ptr, bytes_left - 2);
3723                 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3724                         is_unicode = true;
3725                 else
3726                         is_unicode = false;
3727
3728
3729                 /* skip service field (NB: this field is always ASCII) */
3730                 if (length == 3) {
3731                         if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3732                             (bcc_ptr[2] == 'C')) {
3733                                 cifs_dbg(FYI, "IPC connection\n");
3734                                 tcon->ipc = true;
3735                                 tcon->pipe = true;
3736                         }
3737                 } else if (length == 2) {
3738                         if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3739                                 /* the most common case */
3740                                 cifs_dbg(FYI, "disk share connection\n");
3741                         }
3742                 }
3743                 bcc_ptr += length + 1;
3744                 bytes_left -= (length + 1);
3745                 strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
3746
3747                 /* mostly informational -- no need to fail on error here */
3748                 kfree(tcon->nativeFileSystem);
3749                 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3750                                                       bytes_left, is_unicode,
3751                                                       nls_codepage);
3752
3753                 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3754
3755                 if ((smb_buffer_response->WordCount == 3) ||
3756                          (smb_buffer_response->WordCount == 7))
3757                         /* field is in same location */
3758                         tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3759                 else
3760                         tcon->Flags = 0;
3761                 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3762         }
3763
3764         cifs_buf_release(smb_buffer);
3765         return rc;
3766 }
3767
3768 static void delayed_free(struct rcu_head *p)
3769 {
3770         struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3771
3772         unload_nls(cifs_sb->local_nls);
3773         smb3_cleanup_fs_context(cifs_sb->ctx);
3774         kfree(cifs_sb);
3775 }
3776
3777 void
3778 cifs_umount(struct cifs_sb_info *cifs_sb)
3779 {
3780         struct rb_root *root = &cifs_sb->tlink_tree;
3781         struct rb_node *node;
3782         struct tcon_link *tlink;
3783
3784         cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3785
3786         spin_lock(&cifs_sb->tlink_tree_lock);
3787         while ((node = rb_first(root))) {
3788                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3789                 cifs_get_tlink(tlink);
3790                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3791                 rb_erase(node, root);
3792
3793                 spin_unlock(&cifs_sb->tlink_tree_lock);
3794                 cifs_put_tlink(tlink);
3795                 spin_lock(&cifs_sb->tlink_tree_lock);
3796         }
3797         spin_unlock(&cifs_sb->tlink_tree_lock);
3798
3799         kfree(cifs_sb->prepath);
3800         call_rcu(&cifs_sb->rcu, delayed_free);
3801 }
3802
3803 int
3804 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
3805                         struct TCP_Server_Info *server)
3806 {
3807         int rc = 0;
3808
3809         if (!server->ops->need_neg || !server->ops->negotiate)
3810                 return -ENOSYS;
3811
3812         /* only send once per connect */
3813         spin_lock(&server->srv_lock);
3814         if (server->tcpStatus != CifsGood &&
3815             server->tcpStatus != CifsNew &&
3816             server->tcpStatus != CifsNeedNegotiate) {
3817                 spin_unlock(&server->srv_lock);
3818                 return -EHOSTDOWN;
3819         }
3820
3821         if (!server->ops->need_neg(server) &&
3822             server->tcpStatus == CifsGood) {
3823                 spin_unlock(&server->srv_lock);
3824                 return 0;
3825         }
3826
3827         server->tcpStatus = CifsInNegotiate;
3828         spin_unlock(&server->srv_lock);
3829
3830         rc = server->ops->negotiate(xid, ses, server);
3831         if (rc == 0) {
3832                 spin_lock(&server->srv_lock);
3833                 if (server->tcpStatus == CifsInNegotiate)
3834                         server->tcpStatus = CifsGood;
3835                 else
3836                         rc = -EHOSTDOWN;
3837                 spin_unlock(&server->srv_lock);
3838         } else {
3839                 spin_lock(&server->srv_lock);
3840                 if (server->tcpStatus == CifsInNegotiate)
3841                         server->tcpStatus = CifsNeedNegotiate;
3842                 spin_unlock(&server->srv_lock);
3843         }
3844
3845         return rc;
3846 }
3847
3848 int
3849 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3850                    struct TCP_Server_Info *server,
3851                    struct nls_table *nls_info)
3852 {
3853         int rc = -ENOSYS;
3854         struct TCP_Server_Info *pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
3855         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&pserver->dstaddr;
3856         struct sockaddr_in *addr = (struct sockaddr_in *)&pserver->dstaddr;
3857         bool is_binding = false;
3858
3859         spin_lock(&ses->ses_lock);
3860         cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
3861                  __func__, ses->chans_need_reconnect);
3862
3863         if (ses->ses_status != SES_GOOD &&
3864             ses->ses_status != SES_NEW &&
3865             ses->ses_status != SES_NEED_RECON) {
3866                 spin_unlock(&ses->ses_lock);
3867                 return -EHOSTDOWN;
3868         }
3869
3870         /* only send once per connect */
3871         spin_lock(&ses->chan_lock);
3872         if (CIFS_ALL_CHANS_GOOD(ses)) {
3873                 if (ses->ses_status == SES_NEED_RECON)
3874                         ses->ses_status = SES_GOOD;
3875                 spin_unlock(&ses->chan_lock);
3876                 spin_unlock(&ses->ses_lock);
3877                 return 0;
3878         }
3879
3880         cifs_chan_set_in_reconnect(ses, server);
3881         is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
3882         spin_unlock(&ses->chan_lock);
3883
3884         if (!is_binding) {
3885                 ses->ses_status = SES_IN_SETUP;
3886
3887                 /* force iface_list refresh */
3888                 ses->iface_last_update = 0;
3889         }
3890         spin_unlock(&ses->ses_lock);
3891
3892         /* update ses ip_addr only for primary chan */
3893         if (server == pserver) {
3894                 if (server->dstaddr.ss_family == AF_INET6)
3895                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
3896                 else
3897                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
3898         }
3899
3900         if (!is_binding) {
3901                 ses->capabilities = server->capabilities;
3902                 if (!linuxExtEnabled)
3903                         ses->capabilities &= (~server->vals->cap_unix);
3904
3905                 if (ses->auth_key.response) {
3906                         cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3907                                  ses->auth_key.response);
3908                         kfree_sensitive(ses->auth_key.response);
3909                         ses->auth_key.response = NULL;
3910                         ses->auth_key.len = 0;
3911                 }
3912         }
3913
3914         cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3915                  server->sec_mode, server->capabilities, server->timeAdj);
3916
3917         if (server->ops->sess_setup)
3918                 rc = server->ops->sess_setup(xid, ses, server, nls_info);
3919
3920         if (rc) {
3921                 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3922                 spin_lock(&ses->ses_lock);
3923                 if (ses->ses_status == SES_IN_SETUP)
3924                         ses->ses_status = SES_NEED_RECON;
3925                 spin_lock(&ses->chan_lock);
3926                 cifs_chan_clear_in_reconnect(ses, server);
3927                 spin_unlock(&ses->chan_lock);
3928                 spin_unlock(&ses->ses_lock);
3929         } else {
3930                 spin_lock(&ses->ses_lock);
3931                 if (ses->ses_status == SES_IN_SETUP)
3932                         ses->ses_status = SES_GOOD;
3933                 spin_lock(&ses->chan_lock);
3934                 cifs_chan_clear_in_reconnect(ses, server);
3935                 cifs_chan_clear_need_reconnect(ses, server);
3936                 spin_unlock(&ses->chan_lock);
3937                 spin_unlock(&ses->ses_lock);
3938         }
3939
3940         return rc;
3941 }
3942
3943 static int
3944 cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3945 {
3946         ctx->sectype = ses->sectype;
3947
3948         /* krb5 is special, since we don't need username or pw */
3949         if (ctx->sectype == Kerberos)
3950                 return 0;
3951
3952         return cifs_set_cifscreds(ctx, ses);
3953 }
3954
3955 static struct cifs_tcon *
3956 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3957 {
3958         int rc;
3959         struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3960         struct cifs_ses *ses;
3961         struct cifs_tcon *tcon = NULL;
3962         struct smb3_fs_context *ctx;
3963
3964         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3965         if (ctx == NULL)
3966                 return ERR_PTR(-ENOMEM);
3967
3968         ctx->local_nls = cifs_sb->local_nls;
3969         ctx->linux_uid = fsuid;
3970         ctx->cred_uid = fsuid;
3971         ctx->UNC = master_tcon->tree_name;
3972         ctx->retry = master_tcon->retry;
3973         ctx->nocase = master_tcon->nocase;
3974         ctx->nohandlecache = master_tcon->nohandlecache;
3975         ctx->local_lease = master_tcon->local_lease;
3976         ctx->no_lease = master_tcon->no_lease;
3977         ctx->resilient = master_tcon->use_resilient;
3978         ctx->persistent = master_tcon->use_persistent;
3979         ctx->handle_timeout = master_tcon->handle_timeout;
3980         ctx->no_linux_ext = !master_tcon->unix_ext;
3981         ctx->linux_ext = master_tcon->posix_extensions;
3982         ctx->sectype = master_tcon->ses->sectype;
3983         ctx->sign = master_tcon->ses->sign;
3984         ctx->seal = master_tcon->seal;
3985         ctx->witness = master_tcon->use_witness;
3986
3987         rc = cifs_set_vol_auth(ctx, master_tcon->ses);
3988         if (rc) {
3989                 tcon = ERR_PTR(rc);
3990                 goto out;
3991         }
3992
3993         /* get a reference for the same TCP session */
3994         spin_lock(&cifs_tcp_ses_lock);
3995         ++master_tcon->ses->server->srv_count;
3996         spin_unlock(&cifs_tcp_ses_lock);
3997
3998         ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
3999         if (IS_ERR(ses)) {
4000                 tcon = (struct cifs_tcon *)ses;
4001                 cifs_put_tcp_session(master_tcon->ses->server, 0);
4002                 goto out;
4003         }
4004
4005         tcon = cifs_get_tcon(ses, ctx);
4006         if (IS_ERR(tcon)) {
4007                 cifs_put_smb_ses(ses);
4008                 goto out;
4009         }
4010
4011 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
4012         if (cap_unix(ses))
4013                 reset_cifs_unix_caps(0, tcon, NULL, ctx);
4014 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
4015
4016 out:
4017         kfree(ctx->username);
4018         kfree_sensitive(ctx->password);
4019         kfree(ctx);
4020
4021         return tcon;
4022 }
4023
4024 struct cifs_tcon *
4025 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
4026 {
4027         return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
4028 }
4029
4030 /* find and return a tlink with given uid */
4031 static struct tcon_link *
4032 tlink_rb_search(struct rb_root *root, kuid_t uid)
4033 {
4034         struct rb_node *node = root->rb_node;
4035         struct tcon_link *tlink;
4036
4037         while (node) {
4038                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
4039
4040                 if (uid_gt(tlink->tl_uid, uid))
4041                         node = node->rb_left;
4042                 else if (uid_lt(tlink->tl_uid, uid))
4043                         node = node->rb_right;
4044                 else
4045                         return tlink;
4046         }
4047         return NULL;
4048 }
4049
4050 /* insert a tcon_link into the tree */
4051 static void
4052 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
4053 {
4054         struct rb_node **new = &(root->rb_node), *parent = NULL;
4055         struct tcon_link *tlink;
4056
4057         while (*new) {
4058                 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
4059                 parent = *new;
4060
4061                 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
4062                         new = &((*new)->rb_left);
4063                 else
4064                         new = &((*new)->rb_right);
4065         }
4066
4067         rb_link_node(&new_tlink->tl_rbnode, parent, new);
4068         rb_insert_color(&new_tlink->tl_rbnode, root);
4069 }
4070
4071 /*
4072  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4073  * current task.
4074  *
4075  * If the superblock doesn't refer to a multiuser mount, then just return
4076  * the master tcon for the mount.
4077  *
4078  * First, search the rbtree for an existing tcon for this fsuid. If one
4079  * exists, then check to see if it's pending construction. If it is then wait
4080  * for construction to complete. Once it's no longer pending, check to see if
4081  * it failed and either return an error or retry construction, depending on
4082  * the timeout.
4083  *
4084  * If one doesn't exist then insert a new tcon_link struct into the tree and
4085  * try to construct a new one.
4086  */
4087 struct tcon_link *
4088 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4089 {
4090         int ret;
4091         kuid_t fsuid = current_fsuid();
4092         struct tcon_link *tlink, *newtlink;
4093
4094         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4095                 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4096
4097         spin_lock(&cifs_sb->tlink_tree_lock);
4098         tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4099         if (tlink)
4100                 cifs_get_tlink(tlink);
4101         spin_unlock(&cifs_sb->tlink_tree_lock);
4102
4103         if (tlink == NULL) {
4104                 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4105                 if (newtlink == NULL)
4106                         return ERR_PTR(-ENOMEM);
4107                 newtlink->tl_uid = fsuid;
4108                 newtlink->tl_tcon = ERR_PTR(-EACCES);
4109                 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4110                 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4111                 cifs_get_tlink(newtlink);
4112
4113                 spin_lock(&cifs_sb->tlink_tree_lock);
4114                 /* was one inserted after previous search? */
4115                 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4116                 if (tlink) {
4117                         cifs_get_tlink(tlink);
4118                         spin_unlock(&cifs_sb->tlink_tree_lock);
4119                         kfree(newtlink);
4120                         goto wait_for_construction;
4121                 }
4122                 tlink = newtlink;
4123                 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4124                 spin_unlock(&cifs_sb->tlink_tree_lock);
4125         } else {
4126 wait_for_construction:
4127                 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4128                                   TASK_INTERRUPTIBLE);
4129                 if (ret) {
4130                         cifs_put_tlink(tlink);
4131                         return ERR_PTR(-ERESTARTSYS);
4132                 }
4133
4134                 /* if it's good, return it */
4135                 if (!IS_ERR(tlink->tl_tcon))
4136                         return tlink;
4137
4138                 /* return error if we tried this already recently */
4139                 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4140                         cifs_put_tlink(tlink);
4141                         return ERR_PTR(-EACCES);
4142                 }
4143
4144                 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4145                         goto wait_for_construction;
4146         }
4147
4148         tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4149         clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4150         wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4151
4152         if (IS_ERR(tlink->tl_tcon)) {
4153                 cifs_put_tlink(tlink);
4154                 return ERR_PTR(-EACCES);
4155         }
4156
4157         return tlink;
4158 }
4159
4160 /*
4161  * periodic workqueue job that scans tcon_tree for a superblock and closes
4162  * out tcons.
4163  */
4164 static void
4165 cifs_prune_tlinks(struct work_struct *work)
4166 {
4167         struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4168                                                     prune_tlinks.work);
4169         struct rb_root *root = &cifs_sb->tlink_tree;
4170         struct rb_node *node;
4171         struct rb_node *tmp;
4172         struct tcon_link *tlink;
4173
4174         /*
4175          * Because we drop the spinlock in the loop in order to put the tlink
4176          * it's not guarded against removal of links from the tree. The only
4177          * places that remove entries from the tree are this function and
4178          * umounts. Because this function is non-reentrant and is canceled
4179          * before umount can proceed, this is safe.
4180          */
4181         spin_lock(&cifs_sb->tlink_tree_lock);
4182         node = rb_first(root);
4183         while (node != NULL) {
4184                 tmp = node;
4185                 node = rb_next(tmp);
4186                 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4187
4188                 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4189                     atomic_read(&tlink->tl_count) != 0 ||
4190                     time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4191                         continue;
4192
4193                 cifs_get_tlink(tlink);
4194                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4195                 rb_erase(tmp, root);
4196
4197                 spin_unlock(&cifs_sb->tlink_tree_lock);
4198                 cifs_put_tlink(tlink);
4199                 spin_lock(&cifs_sb->tlink_tree_lock);
4200         }
4201         spin_unlock(&cifs_sb->tlink_tree_lock);
4202
4203         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4204                                 TLINK_IDLE_EXPIRE);
4205 }
4206
4207 #ifndef CONFIG_CIFS_DFS_UPCALL
4208 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4209 {
4210         int rc;
4211         const struct smb_version_operations *ops = tcon->ses->server->ops;
4212
4213         /* only send once per connect */
4214         spin_lock(&tcon->tc_lock);
4215         if (tcon->status == TID_GOOD) {
4216                 spin_unlock(&tcon->tc_lock);
4217                 return 0;
4218         }
4219
4220         if (tcon->status != TID_NEW &&
4221             tcon->status != TID_NEED_TCON) {
4222                 spin_unlock(&tcon->tc_lock);
4223                 return -EHOSTDOWN;
4224         }
4225
4226         tcon->status = TID_IN_TCON;
4227         spin_unlock(&tcon->tc_lock);
4228
4229         rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
4230         if (rc) {
4231                 spin_lock(&tcon->tc_lock);
4232                 if (tcon->status == TID_IN_TCON)
4233                         tcon->status = TID_NEED_TCON;
4234                 spin_unlock(&tcon->tc_lock);
4235         } else {
4236                 spin_lock(&tcon->tc_lock);
4237                 if (tcon->status == TID_IN_TCON)
4238                         tcon->status = TID_GOOD;
4239                 tcon->need_reconnect = false;
4240                 spin_unlock(&tcon->tc_lock);
4241         }
4242
4243         return rc;
4244 }
4245 #endif