fs/smb/client/connect.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002,2011
   5  *   Author(s): Steve French (sfrench@us.ibm.com)
   6  *
   7  */
   8 #include <linux/fs.h>
   9 #include <linux/net.h>
  10 #include <linux/string.h>
  11 #include <linux/sched/mm.h>
  12 #include <linux/sched/signal.h>
  13 #include <linux/list.h>
  14 #include <linux/wait.h>
  15 #include <linux/slab.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/ctype.h>
  18 #include <linux/utsname.h>
  19 #include <linux/mempool.h>
  20 #include <linux/delay.h>
  21 #include <linux/completion.h>
  22 #include <linux/kthread.h>
  23 #include <linux/pagevec.h>
  24 #include <linux/freezer.h>
  25 #include <linux/namei.h>
  26 #include <linux/uuid.h>
  27 #include <linux/uaccess.h>
  28 #include <asm/processor.h>
  29 #include <linux/inet.h>
  30 #include <linux/module.h>
  31 #include <keys/user-type.h>
  32 #include <net/ipv6.h>
  33 #include <linux/parser.h>
  34 #include <linux/bvec.h>
  35 #include "cifspdu.h"
  36 #include "cifsglob.h"
  37 #include "cifsproto.h"
  38 #include "cifs_unicode.h"
  39 #include "cifs_debug.h"
  40 #include "cifs_fs_sb.h"
  41 #include "ntlmssp.h"
  42 #include "nterr.h"
  43 #include "rfc1002pdu.h"
  44 #include "fscache.h"
  45 #include "smb2proto.h"
  46 #include "smbdirect.h"
  47 #include "dns_resolve.h"
  48 #ifdef CONFIG_CIFS_DFS_UPCALL
  49 #include "dfs.h"
  50 #include "dfs_cache.h"
  51 #endif
  52 #include "fs_context.h"
  53 #include "cifs_swn.h"
  54
  55 extern mempool_t *cifs_req_poolp;
  56 extern bool disable_legacy_dialects;
  57
  58 /* FIXME: should these be tunable? */
  59 #define TLINK_ERROR_EXPIRE      (1 * HZ)
  60 #define TLINK_IDLE_EXPIRE       (600 * HZ)
  61
  62 /* Drop the connection to not overload the server */
  63 #define MAX_STATUS_IO_TIMEOUT   5
  64
  65 static int ip_connect(struct TCP_Server_Info *server);
  66 static int generic_ip_connect(struct TCP_Server_Info *server);
  67 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
  68 static void cifs_prune_tlinks(struct work_struct *work);
  69
  70 /*
  71  * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
  72  * get their ip addresses changed at some point.
  73  *
  74  * This should be called with server->srv_mutex held.
  75  */
  76 static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
  77 {
  78         int rc;
  79         int len;
  80         char *unc;
  81         struct sockaddr_storage ss;
  82
  83         if (!server->hostname)
  84                 return -EINVAL;
  85
  86         /* if server hostname isn't populated, there's nothing to do here */
  87         if (server->hostname[0] == '\0')
  88                 return 0;
  89
  90         len = strlen(server->hostname) + 3;
  91
  92         unc = kmalloc(len, GFP_KERNEL);
  93         if (!unc) {
  94                 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
  95                 return -ENOMEM;
  96         }
  97         scnprintf(unc, len, "\\\\%s", server->hostname);
  98
  99         spin_lock(&server->srv_lock);
 100         ss = server->dstaddr;
 101         spin_unlock(&server->srv_lock);
 102
 103         rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, NULL);
 104         kfree(unc);
 105
 106         if (rc < 0) {
 107                 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
 108                          __func__, server->hostname, rc);
 109         } else {
 110                 spin_lock(&server->srv_lock);
 111                 memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
 112                 spin_unlock(&server->srv_lock);
 113                 rc = 0;
 114         }
 115
 116         return rc;
 117 }
 118
 119 static void smb2_query_server_interfaces(struct work_struct *work)
 120 {
 121         int rc;
 122         int xid;
 123         struct cifs_tcon *tcon = container_of(work,
 124                                         struct cifs_tcon,
 125                                         query_interfaces.work);
 126
 127         /*
 128          * query server network interfaces, in case they change
 129          */
 130         xid = get_xid();
 131         rc = SMB3_request_interfaces(xid, tcon, false);
 132         free_xid(xid);
 133
 134         if (rc) {
 135                 if (rc == -EOPNOTSUPP)
 136                         return;
 137
 138                 cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
 139                                 __func__, rc);
 140         }
 141
 142         queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
 143                            (SMB_INTERFACE_POLL_INTERVAL * HZ));
 144 }
 145
 146 /*
 147  * Update the tcpStatus for the server.
 148  * This is used to signal the cifsd thread to call cifs_reconnect
 149  * ONLY cifsd thread should call cifs_reconnect. For any other
 150  * thread, use this function
 151  *
 152  * @server: the tcp ses for which reconnect is needed
 153  * @all_channels: if this needs to be done for all channels
 154  */
 155 void
 156 cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
 157                                 bool all_channels)
 158 {
 159         struct TCP_Server_Info *pserver;
 160         struct cifs_ses *ses;
 161         int i;
 162
 163         /* If server is a channel, select the primary channel */
 164         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
 165
 166         /* if we need to signal just this channel */
 167         if (!all_channels) {
 168                 spin_lock(&server->srv_lock);
 169                 if (server->tcpStatus != CifsExiting)
 170                         server->tcpStatus = CifsNeedReconnect;
 171                 spin_unlock(&server->srv_lock);
 172                 return;
 173         }
 174
 175         spin_lock(&cifs_tcp_ses_lock);
 176         list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
 177                 spin_lock(&ses->chan_lock);
 178                 for (i = 0; i < ses->chan_count; i++) {
 179                         if (!ses->chans[i].server)
 180                                 continue;
 181
 182                         spin_lock(&ses->chans[i].server->srv_lock);
 183                         if (ses->chans[i].server->tcpStatus != CifsExiting)
 184                                 ses->chans[i].server->tcpStatus = CifsNeedReconnect;
 185                         spin_unlock(&ses->chans[i].server->srv_lock);
 186                 }
 187                 spin_unlock(&ses->chan_lock);
 188         }
 189         spin_unlock(&cifs_tcp_ses_lock);
 190 }
 191
 192 /*
 193  * Mark all sessions and tcons for reconnect.
 194  * IMPORTANT: make sure that this gets called only from
 195  * cifsd thread. For any other thread, use
 196  * cifs_signal_cifsd_for_reconnect
 197  *
 198  * @server: the tcp ses for which reconnect is needed
 199  * @server needs to be previously set to CifsNeedReconnect.
 200  * @mark_smb_session: whether even sessions need to be marked
 201  */
 202 void
 203 cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
 204                                       bool mark_smb_session)
 205 {
 206         struct TCP_Server_Info *pserver;
 207         struct cifs_ses *ses, *nses;
 208         struct cifs_tcon *tcon;
 209
 210         /*
 211          * before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
 212          * are not used until reconnected.
 213          */
 214         cifs_dbg(FYI, "%s: marking necessary sessions and tcons for reconnect\n", __func__);
 215
 216         /* If server is a channel, select the primary channel */
 217         pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
 218
 219         /*
 220          * if the server has been marked for termination, there is a
 221          * chance that the remaining channels all need reconnect. To be
 222          * on the safer side, mark the session and trees for reconnect
 223          * for this scenario. This might cause a few redundant session
 224          * setup and tree connect requests, but it is better than not doing
 225          * a tree connect when needed, and all following requests failing
 226          */
 227         if (server->terminate) {
 228                 mark_smb_session = true;
 229                 server = pserver;
 230         }
 231
 232         spin_lock(&cifs_tcp_ses_lock);
 233         list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
 234                 /* check if iface is still active */
 235                 spin_lock(&ses->chan_lock);
 236                 if (cifs_ses_get_chan_index(ses, server) ==
 237                     CIFS_INVAL_CHAN_INDEX) {
 238                         spin_unlock(&ses->chan_lock);
 239                         continue;
 240                 }
 241
 242                 if (!cifs_chan_is_iface_active(ses, server)) {
 243                         spin_unlock(&ses->chan_lock);
 244                         cifs_chan_update_iface(ses, server);
 245                         spin_lock(&ses->chan_lock);
 246                 }
 247
 248                 if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
 249                         spin_unlock(&ses->chan_lock);
 250                         continue;
 251                 }
 252
 253                 if (mark_smb_session)
 254                         CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses);
 255                 else
 256                         cifs_chan_set_need_reconnect(ses, server);
 257
 258                 cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
 259                          __func__, ses->chans_need_reconnect);
 260
 261                 /* If all channels need reconnect, then tcon needs reconnect */
 262                 if (!mark_smb_session && !CIFS_ALL_CHANS_NEED_RECONNECT(ses)) {
 263                         spin_unlock(&ses->chan_lock);
 264                         continue;
 265                 }
 266                 spin_unlock(&ses->chan_lock);
 267
 268                 spin_lock(&ses->ses_lock);
 269                 ses->ses_status = SES_NEED_RECON;
 270                 spin_unlock(&ses->ses_lock);
 271
 272                 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
 273                         tcon->need_reconnect = true;
 274                         spin_lock(&tcon->tc_lock);
 275                         tcon->status = TID_NEED_RECON;
 276                         spin_unlock(&tcon->tc_lock);
 277
 278                         cancel_delayed_work(&tcon->query_interfaces);
 279                 }
 280                 if (ses->tcon_ipc) {
 281                         ses->tcon_ipc->need_reconnect = true;
 282                         spin_lock(&ses->tcon_ipc->tc_lock);
 283                         ses->tcon_ipc->status = TID_NEED_RECON;
 284                         spin_unlock(&ses->tcon_ipc->tc_lock);
 285                 }
 286         }
 287         spin_unlock(&cifs_tcp_ses_lock);
 288 }
 289
 290 static void
 291 cifs_abort_connection(struct TCP_Server_Info *server)
 292 {
 293         struct mid_q_entry *mid, *nmid;
 294         struct list_head retry_list;
 295
 296         server->maxBuf = 0;
 297         server->max_read = 0;
 298
 299         /* do not want to be sending data on a socket we are freeing */
 300         cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
 301         cifs_server_lock(server);
 302         if (server->ssocket) {
 303                 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
 304                          server->ssocket->flags);
 305                 kernel_sock_shutdown(server->ssocket, SHUT_WR);
 306                 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
 307                          server->ssocket->flags);
 308                 sock_release(server->ssocket);
 309                 server->ssocket = NULL;
 310         }
 311         server->sequence_number = 0;
 312         server->session_estab = false;
 313         kfree_sensitive(server->session_key.response);
 314         server->session_key.response = NULL;
 315         server->session_key.len = 0;
 316         server->lstrp = jiffies;
 317
 318         /* mark submitted MIDs for retry and issue callback */
 319         INIT_LIST_HEAD(&retry_list);
 320         cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
 321         spin_lock(&server->mid_lock);
 322         list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
 323                 kref_get(&mid->refcount);
 324                 if (mid->mid_state == MID_REQUEST_SUBMITTED)
 325                         mid->mid_state = MID_RETRY_NEEDED;
 326                 list_move(&mid->qhead, &retry_list);
 327                 mid->mid_flags |= MID_DELETED;
 328         }
 329         spin_unlock(&server->mid_lock);
 330         cifs_server_unlock(server);
 331
 332         cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
 333         list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
 334                 list_del_init(&mid->qhead);
 335                 mid->callback(mid);
 336                 release_mid(mid);
 337         }
 338
 339         if (cifs_rdma_enabled(server)) {
 340                 cifs_server_lock(server);
 341                 smbd_destroy(server);
 342                 cifs_server_unlock(server);
 343         }
 344 }
 345
 346 static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
 347 {
 348         spin_lock(&server->srv_lock);
 349         server->nr_targets = num_targets;
 350         if (server->tcpStatus == CifsExiting) {
 351                 /* the demux thread will exit normally next time through the loop */
 352                 spin_unlock(&server->srv_lock);
 353                 wake_up(&server->response_q);
 354                 return false;
 355         }
 356
 357         cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
 358         trace_smb3_reconnect(server->CurrentMid, server->conn_id,
 359                              server->hostname);
 360         server->tcpStatus = CifsNeedReconnect;
 361
 362         spin_unlock(&server->srv_lock);
 363         return true;
 364 }
 365
 366 /*
 367  * cifs tcp session reconnection
 368  *
 369  * mark tcp session as reconnecting so temporarily locked
 370  * mark all smb sessions as reconnecting for tcp session
 371  * reconnect tcp session
 372  * wake up waiters on reconnection? - (not needed currently)
 373  *
 374  * if mark_smb_session is passed as true, unconditionally mark
 375  * the smb session (and tcon) for reconnect as well. This value
 376  * doesn't really matter for non-multichannel scenario.
 377  *
 378  */
 379 static int __cifs_reconnect(struct TCP_Server_Info *server,
 380                             bool mark_smb_session)
 381 {
 382         int rc = 0;
 383
 384         if (!cifs_tcp_ses_needs_reconnect(server, 1))
 385                 return 0;
 386
 387         cifs_mark_tcp_ses_conns_for_reconnect(server, mark_smb_session);
 388
 389         cifs_abort_connection(server);
 390
 391         do {
 392                 try_to_freeze();
 393                 cifs_server_lock(server);
 394
 395                 if (!cifs_swn_set_server_dstaddr(server)) {
 396                         /* resolve the hostname again to make sure that IP address is up-to-date */
 397                         rc = reconn_set_ipaddr_from_hostname(server);
 398                         cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
 399                 }
 400
 401                 if (cifs_rdma_enabled(server))
 402                         rc = smbd_reconnect(server);
 403                 else
 404                         rc = generic_ip_connect(server);
 405                 if (rc) {
 406                         cifs_server_unlock(server);
 407                         cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
 408                         msleep(3000);
 409                 } else {
 410                         atomic_inc(&tcpSesReconnectCount);
 411                         set_credits(server, 1);
 412                         spin_lock(&server->srv_lock);
 413                         if (server->tcpStatus != CifsExiting)
 414                                 server->tcpStatus = CifsNeedNegotiate;
 415                         spin_unlock(&server->srv_lock);
 416                         cifs_swn_reset_server_dstaddr(server);
 417                         cifs_server_unlock(server);
 418                         mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 419                 }
 420         } while (server->tcpStatus == CifsNeedReconnect);
 421
 422         spin_lock(&server->srv_lock);
 423         if (server->tcpStatus == CifsNeedNegotiate)
 424                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 425         spin_unlock(&server->srv_lock);
 426
 427         wake_up(&server->response_q);
 428         return rc;
 429 }
 430
 431 #ifdef CONFIG_CIFS_DFS_UPCALL
 432 static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
 433 {
 434         int rc;
 435         char *hostname;
 436
 437         if (!cifs_swn_set_server_dstaddr(server)) {
 438                 if (server->hostname != target) {
 439                         hostname = extract_hostname(target);
 440                         if (!IS_ERR(hostname)) {
 441                                 spin_lock(&server->srv_lock);
 442                                 kfree(server->hostname);
 443                                 server->hostname = hostname;
 444                                 spin_unlock(&server->srv_lock);
 445                         } else {
 446                                 cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
 447                                          __func__, PTR_ERR(hostname));
 448                                 cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
 449                                          server->hostname);
 450                         }
 451                 }
 452                 /* resolve the hostname again to make sure that IP address is up-to-date. */
 453                 rc = reconn_set_ipaddr_from_hostname(server);
 454                 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
 455         }
 456         /* Reconnect the socket */
 457         if (cifs_rdma_enabled(server))
 458                 rc = smbd_reconnect(server);
 459         else
 460                 rc = generic_ip_connect(server);
 461
 462         return rc;
 463 }
 464
 465 static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
 466                                      struct dfs_cache_tgt_iterator **target_hint)
 467 {
 468         int rc;
 469         struct dfs_cache_tgt_iterator *tit;
 470
 471         *target_hint = NULL;
 472
 473         /* If dfs target list is empty, then reconnect to last server */
 474         tit = dfs_cache_get_tgt_iterator(tl);
 475         if (!tit)
 476                 return __reconnect_target_unlocked(server, server->hostname);
 477
 478         /* Otherwise, try every dfs target in @tl */
 479         for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
 480                 rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
 481                 if (!rc) {
 482                         *target_hint = tit;
 483                         break;
 484                 }
 485         }
 486         return rc;
 487 }
 488
 489 static int reconnect_dfs_server(struct TCP_Server_Info *server)
 490 {
 491         struct dfs_cache_tgt_iterator *target_hint = NULL;
 492
 493         DFS_CACHE_TGT_LIST(tl);
 494         int num_targets = 0;
 495         int rc = 0;
 496
 497         /*
 498          * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
 499          *
 500          * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
 501          * targets (server->nr_targets).  It's also possible that the cached referral was cleared
 502          * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
 503          * refreshing the referral, so, in this case, default it to 1.
 504          */
 505         mutex_lock(&server->refpath_lock);
 506         if (!dfs_cache_noreq_find(server->leaf_fullpath + 1, NULL, &tl))
 507                 num_targets = dfs_cache_get_nr_tgts(&tl);
 508         mutex_unlock(&server->refpath_lock);
 509         if (!num_targets)
 510                 num_targets = 1;
 511
 512         if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
 513                 return 0;
 514
 515         /*
 516          * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
 517          * different server or share during failover.  It could be improved by adding some logic to
 518          * only do that in case it connects to a different server or share, though.
 519          */
 520         cifs_mark_tcp_ses_conns_for_reconnect(server, true);
 521
 522         cifs_abort_connection(server);
 523
 524         do {
 525                 try_to_freeze();
 526                 cifs_server_lock(server);
 527
 528                 rc = reconnect_target_unlocked(server, &tl, &target_hint);
 529                 if (rc) {
 530                         /* Failed to reconnect socket */
 531                         cifs_server_unlock(server);
 532                         cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
 533                         msleep(3000);
 534                         continue;
 535                 }
 536                 /*
 537                  * Socket was created.  Update tcp session status to CifsNeedNegotiate so that a
 538                  * process waiting for reconnect will know it needs to re-establish session and tcon
 539                  * through the reconnected target server.
 540                  */
 541                 atomic_inc(&tcpSesReconnectCount);
 542                 set_credits(server, 1);
 543                 spin_lock(&server->srv_lock);
 544                 if (server->tcpStatus != CifsExiting)
 545                         server->tcpStatus = CifsNeedNegotiate;
 546                 spin_unlock(&server->srv_lock);
 547                 cifs_swn_reset_server_dstaddr(server);
 548                 cifs_server_unlock(server);
 549                 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
 550         } while (server->tcpStatus == CifsNeedReconnect);
 551
 552         mutex_lock(&server->refpath_lock);
 553         dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, target_hint);
 554         mutex_unlock(&server->refpath_lock);
 555         dfs_cache_free_tgts(&tl);
 556
 557         /* Need to set up echo worker again once connection has been established */
 558         spin_lock(&server->srv_lock);
 559         if (server->tcpStatus == CifsNeedNegotiate)
 560                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 561         spin_unlock(&server->srv_lock);
 562
 563         wake_up(&server->response_q);
 564         return rc;
 565 }
 566
 567 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 568 {
 569         mutex_lock(&server->refpath_lock);
 570         if (!server->leaf_fullpath) {
 571                 mutex_unlock(&server->refpath_lock);
 572                 return __cifs_reconnect(server, mark_smb_session);
 573         }
 574         mutex_unlock(&server->refpath_lock);
 575
 576         return reconnect_dfs_server(server);
 577 }
 578 #else
 579 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
 580 {
 581         return __cifs_reconnect(server, mark_smb_session);
 582 }
 583 #endif
 584
 585 static void
 586 cifs_echo_request(struct work_struct *work)
 587 {
 588         int rc;
 589         struct TCP_Server_Info *server = container_of(work,
 590                                         struct TCP_Server_Info, echo.work);
 591
 592         /*
 593          * We cannot send an echo if it is disabled.
 594          * Also, no need to ping if we got a response recently.
 595          */
 596
 597         if (server->tcpStatus == CifsNeedReconnect ||
 598             server->tcpStatus == CifsExiting ||
 599             server->tcpStatus == CifsNew ||
 600             (server->ops->can_echo && !server->ops->can_echo(server)) ||
 601             time_before(jiffies, server->lstrp + server->echo_interval - HZ))
 602                 goto requeue_echo;
 603
 604         rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
 605         cifs_server_dbg(FYI, "send echo request: rc = %d\n", rc);
 606
 607         /* Check witness registrations */
 608         cifs_swn_check();
 609
 610 requeue_echo:
 611         queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
 612 }
 613
 614 static bool
 615 allocate_buffers(struct TCP_Server_Info *server)
 616 {
 617         if (!server->bigbuf) {
 618                 server->bigbuf = (char *)cifs_buf_get();
 619                 if (!server->bigbuf) {
 620                         cifs_server_dbg(VFS, "No memory for large SMB response\n");
 621                         msleep(3000);
 622                         /* retry will check if exiting */
 623                         return false;
 624                 }
 625         } else if (server->large_buf) {
 626                 /* we are reusing a dirty large buf, clear its start */
 627                 memset(server->bigbuf, 0, HEADER_SIZE(server));
 628         }
 629
 630         if (!server->smallbuf) {
 631                 server->smallbuf = (char *)cifs_small_buf_get();
 632                 if (!server->smallbuf) {
 633                         cifs_server_dbg(VFS, "No memory for SMB response\n");
 634                         msleep(1000);
 635                         /* retry will check if exiting */
 636                         return false;
 637                 }
 638                 /* beginning of smb buffer is cleared in our buf_get */
 639         } else {
 640                 /* if existing small buf clear beginning */
 641                 memset(server->smallbuf, 0, HEADER_SIZE(server));
 642         }
 643
 644         return true;
 645 }
 646
 647 static bool
 648 server_unresponsive(struct TCP_Server_Info *server)
 649 {
 650         /*
 651          * We need to wait 3 echo intervals to make sure we handle such
 652          * situations right:
 653          * 1s  client sends a normal SMB request
 654          * 2s  client gets a response
 655          * 30s echo workqueue job pops, and decides we got a response recently
 656          *     and don't need to send another
 657          * ...
 658          * 65s kernel_recvmsg times out, and we see that we haven't gotten
 659          *     a response in >60s.
 660          */
 661         spin_lock(&server->srv_lock);
 662         if ((server->tcpStatus == CifsGood ||
 663             server->tcpStatus == CifsNeedNegotiate) &&
 664             (!server->ops->can_echo || server->ops->can_echo(server)) &&
 665             time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
 666                 spin_unlock(&server->srv_lock);
 667                 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
 668                          (3 * server->echo_interval) / HZ);
 669                 cifs_reconnect(server, false);
 670                 return true;
 671         }
 672         spin_unlock(&server->srv_lock);
 673
 674         return false;
 675 }
 676
 677 static inline bool
 678 zero_credits(struct TCP_Server_Info *server)
 679 {
 680         int val;
 681
 682         spin_lock(&server->req_lock);
 683         val = server->credits + server->echo_credits + server->oplock_credits;
 684         if (server->in_flight == 0 && val == 0) {
 685                 spin_unlock(&server->req_lock);
 686                 return true;
 687         }
 688         spin_unlock(&server->req_lock);
 689         return false;
 690 }
 691
 692 static int
 693 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 694 {
 695         int length = 0;
 696         int total_read;
 697
 698         for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 699                 try_to_freeze();
 700
 701                 /* reconnect if no credits and no requests in flight */
 702                 if (zero_credits(server)) {
 703                         cifs_reconnect(server, false);
 704                         return -ECONNABORTED;
 705                 }
 706
 707                 if (server_unresponsive(server))
 708                         return -ECONNABORTED;
 709                 if (cifs_rdma_enabled(server) && server->smbd_conn)
 710                         length = smbd_recv(server->smbd_conn, smb_msg);
 711                 else
 712                         length = sock_recvmsg(server->ssocket, smb_msg, 0);
 713
 714                 spin_lock(&server->srv_lock);
 715                 if (server->tcpStatus == CifsExiting) {
 716                         spin_unlock(&server->srv_lock);
 717                         return -ESHUTDOWN;
 718                 }
 719
 720                 if (server->tcpStatus == CifsNeedReconnect) {
 721                         spin_unlock(&server->srv_lock);
 722                         cifs_reconnect(server, false);
 723                         return -ECONNABORTED;
 724                 }
 725                 spin_unlock(&server->srv_lock);
 726
 727                 if (length == -ERESTARTSYS ||
 728                     length == -EAGAIN ||
 729                     length == -EINTR) {
 730                         /*
 731                          * Minimum sleep to prevent looping, allowing socket
 732                          * to clear and app threads to set tcpStatus
 733                          * CifsNeedReconnect if server hung.
 734                          */
 735                         usleep_range(1000, 2000);
 736                         length = 0;
 737                         continue;
 738                 }
 739
 740                 if (length <= 0) {
 741                         cifs_dbg(FYI, "Received no data or error: %d\n", length);
 742                         cifs_reconnect(server, false);
 743                         return -ECONNABORTED;
 744                 }
 745         }
 746         return total_read;
 747 }
 748
 749 int
 750 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 751                       unsigned int to_read)
 752 {
 753         struct msghdr smb_msg = {};
 754         struct kvec iov = {.iov_base = buf, .iov_len = to_read};
 755
 756         iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
 757
 758         return cifs_readv_from_socket(server, &smb_msg);
 759 }
 760
 761 ssize_t
 762 cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
 763 {
 764         struct msghdr smb_msg = {};
 765
 766         /*
 767          *  iov_iter_discard already sets smb_msg.type and count and iov_offset
 768          *  and cifs_readv_from_socket sets msg_control and msg_controllen
 769          *  so little to initialize in struct msghdr
 770          */
 771         iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
 772
 773         return cifs_readv_from_socket(server, &smb_msg);
 774 }
 775
 776 int
 777 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 778         unsigned int page_offset, unsigned int to_read)
 779 {
 780         struct msghdr smb_msg = {};
 781         struct bio_vec bv;
 782
 783         bvec_set_page(&bv, page, to_read, page_offset);
 784         iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
 785         return cifs_readv_from_socket(server, &smb_msg);
 786 }
 787
 788 int
 789 cifs_read_iter_from_socket(struct TCP_Server_Info *server, struct iov_iter *iter,
 790                            unsigned int to_read)
 791 {
 792         struct msghdr smb_msg = { .msg_iter = *iter };
 793         int ret;
 794
 795         iov_iter_truncate(&smb_msg.msg_iter, to_read);
 796         ret = cifs_readv_from_socket(server, &smb_msg);
 797         if (ret > 0)
 798                 iov_iter_advance(iter, ret);
 799         return ret;
 800 }
 801
 802 static bool
 803 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
 804 {
 805         /*
 806          * The first byte big endian of the length field,
 807          * is actually not part of the length but the type
 808          * with the most common, zero, as regular data.
 809          */
 810         switch (type) {
 811         case RFC1002_SESSION_MESSAGE:
 812                 /* Regular SMB response */
 813                 return true;
 814         case RFC1002_SESSION_KEEP_ALIVE:
 815                 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
 816                 break;
 817         case RFC1002_POSITIVE_SESSION_RESPONSE:
 818                 cifs_dbg(FYI, "RFC 1002 positive session response\n");
 819                 break;
 820         case RFC1002_NEGATIVE_SESSION_RESPONSE:
 821                 /*
 822                  * We get this from Windows 98 instead of an error on
 823                  * SMB negprot response.
 824                  */
 825                 cifs_dbg(FYI, "RFC 1002 negative session response\n");
 826                 /* give server a second to clean up */
 827                 msleep(1000);
 828                 /*
 829                  * Always try 445 first on reconnect since we get NACK
 830                  * on some if we ever connected to port 139 (the NACK
 831                  * is since we do not begin with RFC1001 session
 832                  * initialize frame).
 833                  */
 834                 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
 835                 cifs_reconnect(server, true);
 836                 break;
 837         default:
 838                 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
 839                 cifs_reconnect(server, true);
 840         }
 841
 842         return false;
 843 }
 844
 845 void
 846 dequeue_mid(struct mid_q_entry *mid, bool malformed)
 847 {
 848 #ifdef CONFIG_CIFS_STATS2
 849         mid->when_received = jiffies;
 850 #endif
 851         spin_lock(&mid->server->mid_lock);
 852         if (!malformed)
 853                 mid->mid_state = MID_RESPONSE_RECEIVED;
 854         else
 855                 mid->mid_state = MID_RESPONSE_MALFORMED;
 856         /*
 857          * Trying to handle/dequeue a mid after the send_recv()
 858          * function has finished processing it is a bug.
 859          */
 860         if (mid->mid_flags & MID_DELETED) {
 861                 spin_unlock(&mid->server->mid_lock);
 862                 pr_warn_once("trying to dequeue a deleted mid\n");
 863         } else {
 864                 list_del_init(&mid->qhead);
 865                 mid->mid_flags |= MID_DELETED;
 866                 spin_unlock(&mid->server->mid_lock);
 867         }
 868 }
 869
 870 static unsigned int
 871 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 872 {
 873         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
 874
 875         /*
 876          * SMB1 does not use credits.
 877          */
 878         if (is_smb1(server))
 879                 return 0;
 880
 881         return le16_to_cpu(shdr->CreditRequest);
 882 }
 883
 884 static void
 885 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 886            char *buf, int malformed)
 887 {
 888         if (server->ops->check_trans2 &&
 889             server->ops->check_trans2(mid, server, buf, malformed))
 890                 return;
 891         mid->credits_received = smb2_get_credits_from_hdr(buf, server);
 892         mid->resp_buf = buf;
 893         mid->large_buf = server->large_buf;
 894         /* Was previous buf put in mpx struct for multi-rsp? */
 895         if (!mid->multiRsp) {
 896                 /* smb buffer will be freed by user thread */
 897                 if (server->large_buf)
 898                         server->bigbuf = NULL;
 899                 else
 900                         server->smallbuf = NULL;
 901         }
 902         dequeue_mid(mid, malformed);
 903 }
 904
 905 int
 906 cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
 907 {
 908         bool srv_sign_required = server->sec_mode & server->vals->signing_required;
 909         bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
 910         bool mnt_sign_enabled;
 911
 912         /*
 913          * Is signing required by mnt options? If not then check
 914          * global_secflags to see if it is there.
 915          */
 916         if (!mnt_sign_required)
 917                 mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
 918                                                 CIFSSEC_MUST_SIGN);
 919
 920         /*
 921          * If signing is required then it's automatically enabled too,
 922          * otherwise, check to see if the secflags allow it.
 923          */
 924         mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
 925                                 (global_secflags & CIFSSEC_MAY_SIGN);
 926
 927         /* If server requires signing, does client allow it? */
 928         if (srv_sign_required) {
 929                 if (!mnt_sign_enabled) {
 930                         cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
 931                         return -EOPNOTSUPP;
 932                 }
 933                 server->sign = true;
 934         }
 935
 936         /* If client requires signing, does server allow it? */
 937         if (mnt_sign_required) {
 938                 if (!srv_sign_enabled) {
 939                         cifs_dbg(VFS, "Server does not support signing!\n");
 940                         return -EOPNOTSUPP;
 941                 }
 942                 server->sign = true;
 943         }
 944
 945         if (cifs_rdma_enabled(server) && server->sign)
 946                 cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
 947
 948         return 0;
 949 }
 950
 951 static noinline_for_stack void
 952 clean_demultiplex_info(struct TCP_Server_Info *server)
 953 {
 954         int length;
 955
 956         /* take it off the list, if it's not already */
 957         spin_lock(&server->srv_lock);
 958         list_del_init(&server->tcp_ses_list);
 959         spin_unlock(&server->srv_lock);
 960
 961         cancel_delayed_work_sync(&server->echo);
 962
 963         spin_lock(&server->srv_lock);
 964         server->tcpStatus = CifsExiting;
 965         spin_unlock(&server->srv_lock);
 966         wake_up_all(&server->response_q);
 967
 968         /* check if we have blocked requests that need to free */
 969         spin_lock(&server->req_lock);
 970         if (server->credits <= 0)
 971                 server->credits = 1;
 972         spin_unlock(&server->req_lock);
 973         /*
 974          * Although there should not be any requests blocked on this queue it
 975          * can not hurt to be paranoid and try to wake up requests that may
 976          * haven been blocked when more than 50 at time were on the wire to the
 977          * same server - they now will see the session is in exit state and get
 978          * out of SendReceive.
 979          */
 980         wake_up_all(&server->request_q);
 981         /* give those requests time to exit */
 982         msleep(125);
 983         if (cifs_rdma_enabled(server))
 984                 smbd_destroy(server);
 985         if (server->ssocket) {
 986                 sock_release(server->ssocket);
 987                 server->ssocket = NULL;
 988         }
 989
 990         if (!list_empty(&server->pending_mid_q)) {
 991                 struct list_head dispose_list;
 992                 struct mid_q_entry *mid_entry;
 993                 struct list_head *tmp, *tmp2;
 994
 995                 INIT_LIST_HEAD(&dispose_list);
 996                 spin_lock(&server->mid_lock);
 997                 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 998                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 999                         cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
1000                         kref_get(&mid_entry->refcount);
1001                         mid_entry->mid_state = MID_SHUTDOWN;
1002                         list_move(&mid_entry->qhead, &dispose_list);
1003                         mid_entry->mid_flags |= MID_DELETED;
1004                 }
1005                 spin_unlock(&server->mid_lock);
1006
1007                 /* now walk dispose list and issue callbacks */
1008                 list_for_each_safe(tmp, tmp2, &dispose_list) {
1009                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
1010                         cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
1011                         list_del_init(&mid_entry->qhead);
1012                         mid_entry->callback(mid_entry);
1013                         release_mid(mid_entry);
1014                 }
1015                 /* 1/8th of sec is more than enough time for them to exit */
1016                 msleep(125);
1017         }
1018
1019         if (!list_empty(&server->pending_mid_q)) {
1020                 /*
1021                  * mpx threads have not exited yet give them at least the smb
1022                  * send timeout time for long ops.
1023                  *
1024                  * Due to delays on oplock break requests, we need to wait at
1025                  * least 45 seconds before giving up on a request getting a
1026                  * response and going ahead and killing cifsd.
1027                  */
1028                 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
1029                 msleep(46000);
1030                 /*
1031                  * If threads still have not exited they are probably never
1032                  * coming home not much else we can do but free the memory.
1033                  */
1034         }
1035
1036         kfree(server->leaf_fullpath);
1037         kfree(server);
1038
1039         length = atomic_dec_return(&tcpSesAllocCount);
1040         if (length > 0)
1041                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1042 }
1043
1044 static int
1045 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1046 {
1047         int length;
1048         char *buf = server->smallbuf;
1049         unsigned int pdu_length = server->pdu_size;
1050
1051         /* make sure this will fit in a large buffer */
1052         if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1053             HEADER_PREAMBLE_SIZE(server)) {
1054                 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1055                 cifs_reconnect(server, true);
1056                 return -ECONNABORTED;
1057         }
1058
1059         /* switch to large buffer if too big for a small one */
1060         if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1061                 server->large_buf = true;
1062                 memcpy(server->bigbuf, buf, server->total_read);
1063                 buf = server->bigbuf;
1064         }
1065
1066         /* now read the rest */
1067         length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1068                                        pdu_length - MID_HEADER_SIZE(server));
1069
1070         if (length < 0)
1071                 return length;
1072         server->total_read += length;
1073
1074         dump_smb(buf, server->total_read);
1075
1076         return cifs_handle_standard(server, mid);
1077 }
1078
1079 int
1080 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1081 {
1082         char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1083         int rc;
1084
1085         /*
1086          * We know that we received enough to get to the MID as we
1087          * checked the pdu_length earlier. Now check to see
1088          * if the rest of the header is OK.
1089          *
1090          * 48 bytes is enough to display the header and a little bit
1091          * into the payload for debugging purposes.
1092          */
1093         rc = server->ops->check_message(buf, server->total_read, server);
1094         if (rc)
1095                 cifs_dump_mem("Bad SMB: ", buf,
1096                         min_t(unsigned int, server->total_read, 48));
1097
1098         if (server->ops->is_session_expired &&
1099             server->ops->is_session_expired(buf)) {
1100                 cifs_reconnect(server, true);
1101                 return -1;
1102         }
1103
1104         if (server->ops->is_status_pending &&
1105             server->ops->is_status_pending(buf, server))
1106                 return -1;
1107
1108         if (!mid)
1109                 return rc;
1110
1111         handle_mid(mid, server, buf, rc);
1112         return 0;
1113 }
1114
1115 static void
1116 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1117 {
1118         struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
1119         int scredits, in_flight;
1120
1121         /*
1122          * SMB1 does not use credits.
1123          */
1124         if (is_smb1(server))
1125                 return;
1126
1127         if (shdr->CreditRequest) {
1128                 spin_lock(&server->req_lock);
1129                 server->credits += le16_to_cpu(shdr->CreditRequest);
1130                 scredits = server->credits;
1131                 in_flight = server->in_flight;
1132                 spin_unlock(&server->req_lock);
1133                 wake_up(&server->request_q);
1134
1135                 trace_smb3_hdr_credits(server->CurrentMid,
1136                                 server->conn_id, server->hostname, scredits,
1137                                 le16_to_cpu(shdr->CreditRequest), in_flight);
1138                 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
1139                                 __func__, le16_to_cpu(shdr->CreditRequest),
1140                                 scredits);
1141         }
1142 }
1143
1144
1145 static int
1146 cifs_demultiplex_thread(void *p)
1147 {
1148         int i, num_mids, length;
1149         struct TCP_Server_Info *server = p;
1150         unsigned int pdu_length;
1151         unsigned int next_offset;
1152         char *buf = NULL;
1153         struct task_struct *task_to_wake = NULL;
1154         struct mid_q_entry *mids[MAX_COMPOUND];
1155         char *bufs[MAX_COMPOUND];
1156         unsigned int noreclaim_flag, num_io_timeout = 0;
1157         bool pending_reconnect = false;
1158
1159         noreclaim_flag = memalloc_noreclaim_save();
1160         cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1161
1162         length = atomic_inc_return(&tcpSesAllocCount);
1163         if (length > 1)
1164                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1165
1166         set_freezable();
1167         allow_kernel_signal(SIGKILL);
1168         while (server->tcpStatus != CifsExiting) {
1169                 if (try_to_freeze())
1170                         continue;
1171
1172                 if (!allocate_buffers(server))
1173                         continue;
1174
1175                 server->large_buf = false;
1176                 buf = server->smallbuf;
1177                 pdu_length = 4; /* enough to get RFC1001 header */
1178
1179                 length = cifs_read_from_socket(server, buf, pdu_length);
1180                 if (length < 0)
1181                         continue;
1182
1183                 if (is_smb1(server))
1184                         server->total_read = length;
1185                 else
1186                         server->total_read = 0;
1187
1188                 /*
1189                  * The right amount was read from socket - 4 bytes,
1190                  * so we can now interpret the length field.
1191                  */
1192                 pdu_length = get_rfc1002_length(buf);
1193
1194                 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1195                 if (!is_smb_response(server, buf[0]))
1196                         continue;
1197
1198                 pending_reconnect = false;
1199 next_pdu:
1200                 server->pdu_size = pdu_length;
1201
1202                 /* make sure we have enough to get to the MID */
1203                 if (server->pdu_size < MID_HEADER_SIZE(server)) {
1204                         cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1205                                  server->pdu_size);
1206                         cifs_reconnect(server, true);
1207                         continue;
1208                 }
1209
1210                 /* read down to the MID */
1211                 length = cifs_read_from_socket(server,
1212                              buf + HEADER_PREAMBLE_SIZE(server),
1213                              MID_HEADER_SIZE(server));
1214                 if (length < 0)
1215                         continue;
1216                 server->total_read += length;
1217
1218                 if (server->ops->next_header) {
1219                         if (server->ops->next_header(server, buf, &next_offset)) {
1220                                 cifs_dbg(VFS, "%s: malformed response (next_offset=%u)\n",
1221                                          __func__, next_offset);
1222                                 cifs_reconnect(server, true);
1223                                 continue;
1224                         }
1225                         if (next_offset)
1226                                 server->pdu_size = next_offset;
1227                 }
1228
1229                 memset(mids, 0, sizeof(mids));
1230                 memset(bufs, 0, sizeof(bufs));
1231                 num_mids = 0;
1232
1233                 if (server->ops->is_transform_hdr &&
1234                     server->ops->receive_transform &&
1235                     server->ops->is_transform_hdr(buf)) {
1236                         length = server->ops->receive_transform(server,
1237                                                                 mids,
1238                                                                 bufs,
1239                                                                 &num_mids);
1240                 } else {
1241                         mids[0] = server->ops->find_mid(server, buf);
1242                         bufs[0] = buf;
1243                         num_mids = 1;
1244
1245                         if (!mids[0] || !mids[0]->receive)
1246                                 length = standard_receive3(server, mids[0]);
1247                         else
1248                                 length = mids[0]->receive(server, mids[0]);
1249                 }
1250
1251                 if (length < 0) {
1252                         for (i = 0; i < num_mids; i++)
1253                                 if (mids[i])
1254                                         release_mid(mids[i]);
1255                         continue;
1256                 }
1257
1258                 if (server->ops->is_status_io_timeout &&
1259                     server->ops->is_status_io_timeout(buf)) {
1260                         num_io_timeout++;
1261                         if (num_io_timeout > MAX_STATUS_IO_TIMEOUT) {
1262                                 cifs_server_dbg(VFS,
1263                                                 "Number of request timeouts exceeded %d. Reconnecting",
1264                                                 MAX_STATUS_IO_TIMEOUT);
1265
1266                                 pending_reconnect = true;
1267                                 num_io_timeout = 0;
1268                         }
1269                 }
1270
1271                 server->lstrp = jiffies;
1272
1273                 for (i = 0; i < num_mids; i++) {
1274                         if (mids[i] != NULL) {
1275                                 mids[i]->resp_buf_size = server->pdu_size;
1276
1277                                 if (bufs[i] != NULL) {
1278                                         if (server->ops->is_network_name_deleted &&
1279                                             server->ops->is_network_name_deleted(bufs[i],
1280                                                                                  server)) {
1281                                                 cifs_server_dbg(FYI,
1282                                                                 "Share deleted. Reconnect needed");
1283                                         }
1284                                 }
1285
1286                                 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1287                                         mids[i]->callback(mids[i]);
1288
1289                                 release_mid(mids[i]);
1290                         } else if (server->ops->is_oplock_break &&
1291                                    server->ops->is_oplock_break(bufs[i],
1292                                                                 server)) {
1293                                 smb2_add_credits_from_hdr(bufs[i], server);
1294                                 cifs_dbg(FYI, "Received oplock break\n");
1295                         } else {
1296                                 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1297                                                 atomic_read(&mid_count));
1298                                 cifs_dump_mem("Received Data is: ", bufs[i],
1299                                               HEADER_SIZE(server));
1300                                 smb2_add_credits_from_hdr(bufs[i], server);
1301 #ifdef CONFIG_CIFS_DEBUG2
1302                                 if (server->ops->dump_detail)
1303                                         server->ops->dump_detail(bufs[i],
1304                                                                  server);
1305                                 cifs_dump_mids(server);
1306 #endif /* CIFS_DEBUG2 */
1307                         }
1308                 }
1309
1310                 if (pdu_length > server->pdu_size) {
1311                         if (!allocate_buffers(server))
1312                                 continue;
1313                         pdu_length -= server->pdu_size;
1314                         server->total_read = 0;
1315                         server->large_buf = false;
1316                         buf = server->smallbuf;
1317                         goto next_pdu;
1318                 }
1319
1320                 /* do this reconnect at the very end after processing all MIDs */
1321                 if (pending_reconnect)
1322                         cifs_reconnect(server, true);
1323
1324         } /* end while !EXITING */
1325
1326         /* buffer usually freed in free_mid - need to free it here on exit */
1327         cifs_buf_release(server->bigbuf);
1328         if (server->smallbuf) /* no sense logging a debug message if NULL */
1329                 cifs_small_buf_release(server->smallbuf);
1330
1331         task_to_wake = xchg(&server->tsk, NULL);
1332         clean_demultiplex_info(server);
1333
1334         /* if server->tsk was NULL then wait for a signal before exiting */
1335         if (!task_to_wake) {
1336                 set_current_state(TASK_INTERRUPTIBLE);
1337                 while (!signal_pending(current)) {
1338                         schedule();
1339                         set_current_state(TASK_INTERRUPTIBLE);
1340                 }
1341                 set_current_state(TASK_RUNNING);
1342         }
1343
1344         memalloc_noreclaim_restore(noreclaim_flag);
1345         module_put_and_kthread_exit(0);
1346 }
1347
1348 int
1349 cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
1350 {
1351         struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1352         struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1353         struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1354         struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1355
1356         switch (srcaddr->sa_family) {
1357         case AF_UNSPEC:
1358                 switch (rhs->sa_family) {
1359                 case AF_UNSPEC:
1360                         return 0;
1361                 case AF_INET:
1362                 case AF_INET6:
1363                         return 1;
1364                 default:
1365                         return -1;
1366                 }
1367         case AF_INET: {
1368                 switch (rhs->sa_family) {
1369                 case AF_UNSPEC:
1370                         return -1;
1371                 case AF_INET:
1372                         return memcmp(saddr4, vaddr4,
1373                                       sizeof(struct sockaddr_in));
1374                 case AF_INET6:
1375                         return 1;
1376                 default:
1377                         return -1;
1378                 }
1379         }
1380         case AF_INET6: {
1381                 switch (rhs->sa_family) {
1382                 case AF_UNSPEC:
1383                 case AF_INET:
1384                         return -1;
1385                 case AF_INET6:
1386                         return memcmp(saddr6,
1387                                       vaddr6,
1388                                       sizeof(struct sockaddr_in6));
1389                 default:
1390                         return -1;
1391                 }
1392         }
1393         default:
1394                 return -1; /* don't expect to be here */
1395         }
1396 }
1397
1398 /*
1399  * Returns true if srcaddr isn't specified and rhs isn't specified, or
1400  * if srcaddr is specified and matches the IP address of the rhs argument
1401  */
1402 bool
1403 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1404 {
1405         switch (srcaddr->sa_family) {
1406         case AF_UNSPEC:
1407                 return (rhs->sa_family == AF_UNSPEC);
1408         case AF_INET: {
1409                 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1410                 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1411
1412                 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1413         }
1414         case AF_INET6: {
1415                 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1416                 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1417
1418                 return (ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr)
1419                         && saddr6->sin6_scope_id == vaddr6->sin6_scope_id);
1420         }
1421         default:
1422                 WARN_ON(1);
1423                 return false; /* don't expect to be here */
1424         }
1425 }
1426
1427 /*
1428  * If no port is specified in addr structure, we try to match with 445 port
1429  * and if it fails - with 139 ports. It should be called only if address
1430  * families of server and addr are equal.
1431  */
1432 static bool
1433 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1434 {
1435         __be16 port, *sport;
1436
1437         /* SMBDirect manages its own ports, don't match it here */
1438         if (server->rdma)
1439                 return true;
1440
1441         switch (addr->sa_family) {
1442         case AF_INET:
1443                 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1444                 port = ((struct sockaddr_in *) addr)->sin_port;
1445                 break;
1446         case AF_INET6:
1447                 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1448                 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1449                 break;
1450         default:
1451                 WARN_ON(1);
1452                 return false;
1453         }
1454
1455         if (!port) {
1456                 port = htons(CIFS_PORT);
1457                 if (port == *sport)
1458                         return true;
1459
1460                 port = htons(RFC1001_PORT);
1461         }
1462
1463         return port == *sport;
1464 }
1465
1466 static bool match_server_address(struct TCP_Server_Info *server, struct sockaddr *addr)
1467 {
1468         if (!cifs_match_ipaddr(addr, (struct sockaddr *)&server->dstaddr))
1469                 return false;
1470
1471         return true;
1472 }
1473
1474 static bool
1475 match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1476 {
1477         /*
1478          * The select_sectype function should either return the ctx->sectype
1479          * that was specified, or "Unspecified" if that sectype was not
1480          * compatible with the given NEGOTIATE request.
1481          */
1482         if (server->ops->select_sectype(server, ctx->sectype)
1483              == Unspecified)
1484                 return false;
1485
1486         /*
1487          * Now check if signing mode is acceptable. No need to check
1488          * global_secflags at this point since if MUST_SIGN is set then
1489          * the server->sign had better be too.
1490          */
1491         if (ctx->sign && !server->sign)
1492                 return false;
1493
1494         return true;
1495 }
1496
1497 /* this function must be called with srv_lock held */
1498 static int match_server(struct TCP_Server_Info *server,
1499                         struct smb3_fs_context *ctx,
1500                         bool match_super)
1501 {
1502         struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1503
1504         lockdep_assert_held(&server->srv_lock);
1505
1506         if (ctx->nosharesock)
1507                 return 0;
1508
1509         /* this server does not share socket */
1510         if (server->nosharesock)
1511                 return 0;
1512
1513         /* If multidialect negotiation see if existing sessions match one */
1514         if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1515                 if (server->vals->protocol_id < SMB30_PROT_ID)
1516                         return 0;
1517         } else if (strcmp(ctx->vals->version_string,
1518                    SMBDEFAULT_VERSION_STRING) == 0) {
1519                 if (server->vals->protocol_id < SMB21_PROT_ID)
1520                         return 0;
1521         } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1522                 return 0;
1523
1524         if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1525                 return 0;
1526
1527         if (!cifs_match_ipaddr((struct sockaddr *)&ctx->srcaddr,
1528                                (struct sockaddr *)&server->srcaddr))
1529                 return 0;
1530         /*
1531          * When matching cifs.ko superblocks (@match_super == true), we can't
1532          * really match either @server->leaf_fullpath or @server->dstaddr
1533          * directly since this @server might belong to a completely different
1534          * server -- in case of domain-based DFS referrals or DFS links -- as
1535          * provided earlier by mount(2) through 'source' and 'ip' options.
1536          *
1537          * Otherwise, match the DFS referral in @server->leaf_fullpath or the
1538          * destination address in @server->dstaddr.
1539          *
1540          * When using 'nodfs' mount option, we avoid sharing it with DFS
1541          * connections as they might failover.
1542          */
1543         if (!match_super) {
1544                 if (!ctx->nodfs) {
1545                         if (server->leaf_fullpath) {
1546                                 if (!ctx->leaf_fullpath ||
1547                                     strcasecmp(server->leaf_fullpath,
1548                                                ctx->leaf_fullpath))
1549                                         return 0;
1550                         } else if (ctx->leaf_fullpath) {
1551                                 return 0;
1552                         }
1553                 } else if (server->leaf_fullpath) {
1554                         return 0;
1555                 }
1556         }
1557
1558         /*
1559          * Match for a regular connection (address/hostname/port) which has no
1560          * DFS referrals set.
1561          */
1562         if (!server->leaf_fullpath &&
1563             (strcasecmp(server->hostname, ctx->server_hostname) ||
1564              !match_server_address(server, addr) ||
1565              !match_port(server, addr)))
1566                 return 0;
1567
1568         if (!match_security(server, ctx))
1569                 return 0;
1570
1571         if (server->echo_interval != ctx->echo_interval * HZ)
1572                 return 0;
1573
1574         if (server->rdma != ctx->rdma)
1575                 return 0;
1576
1577         if (server->ignore_signature != ctx->ignore_signature)
1578                 return 0;
1579
1580         if (server->min_offload != ctx->min_offload)
1581                 return 0;
1582
1583         if (server->retrans != ctx->retrans)
1584                 return 0;
1585
1586         return 1;
1587 }
1588
1589 struct TCP_Server_Info *
1590 cifs_find_tcp_session(struct smb3_fs_context *ctx)
1591 {
1592         struct TCP_Server_Info *server;
1593
1594         spin_lock(&cifs_tcp_ses_lock);
1595         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1596                 spin_lock(&server->srv_lock);
1597                 /*
1598                  * Skip ses channels since they're only handled in lower layers
1599                  * (e.g. cifs_send_recv).
1600                  */
1601                 if (SERVER_IS_CHAN(server) ||
1602                     !match_server(server, ctx, false)) {
1603                         spin_unlock(&server->srv_lock);
1604                         continue;
1605                 }
1606                 spin_unlock(&server->srv_lock);
1607
1608                 ++server->srv_count;
1609                 spin_unlock(&cifs_tcp_ses_lock);
1610                 cifs_dbg(FYI, "Existing tcp session with server found\n");
1611                 return server;
1612         }
1613         spin_unlock(&cifs_tcp_ses_lock);
1614         return NULL;
1615 }
1616
1617 void
1618 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1619 {
1620         struct task_struct *task;
1621
1622         spin_lock(&cifs_tcp_ses_lock);
1623         if (--server->srv_count > 0) {
1624                 spin_unlock(&cifs_tcp_ses_lock);
1625                 return;
1626         }
1627
1628         /* srv_count can never go negative */
1629         WARN_ON(server->srv_count < 0);
1630
1631         put_net(cifs_net_ns(server));
1632
1633         list_del_init(&server->tcp_ses_list);
1634         spin_unlock(&cifs_tcp_ses_lock);
1635
1636         cancel_delayed_work_sync(&server->echo);
1637
1638         if (from_reconnect)
1639                 /*
1640                  * Avoid deadlock here: reconnect work calls
1641                  * cifs_put_tcp_session() at its end. Need to be sure
1642                  * that reconnect work does nothing with server pointer after
1643                  * that step.
1644                  */
1645                 cancel_delayed_work(&server->reconnect);
1646         else
1647                 cancel_delayed_work_sync(&server->reconnect);
1648
1649         /* For secondary channels, we pick up ref-count on the primary server */
1650         if (SERVER_IS_CHAN(server))
1651                 cifs_put_tcp_session(server->primary_server, from_reconnect);
1652
1653         spin_lock(&server->srv_lock);
1654         server->tcpStatus = CifsExiting;
1655         spin_unlock(&server->srv_lock);
1656
1657         cifs_crypto_secmech_release(server);
1658
1659         kfree_sensitive(server->session_key.response);
1660         server->session_key.response = NULL;
1661         server->session_key.len = 0;
1662         kfree(server->hostname);
1663         server->hostname = NULL;
1664
1665         task = xchg(&server->tsk, NULL);
1666         if (task)
1667                 send_sig(SIGKILL, task, 1);
1668 }
1669
1670 struct TCP_Server_Info *
1671 cifs_get_tcp_session(struct smb3_fs_context *ctx,
1672                      struct TCP_Server_Info *primary_server)
1673 {
1674         struct TCP_Server_Info *tcp_ses = NULL;
1675         int rc;
1676
1677         cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1678
1679         /* see if we already have a matching tcp_ses */
1680         tcp_ses = cifs_find_tcp_session(ctx);
1681         if (tcp_ses)
1682                 return tcp_ses;
1683
1684         tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1685         if (!tcp_ses) {
1686                 rc = -ENOMEM;
1687                 goto out_err;
1688         }
1689
1690         tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
1691         if (!tcp_ses->hostname) {
1692                 rc = -ENOMEM;
1693                 goto out_err;
1694         }
1695
1696         if (ctx->leaf_fullpath) {
1697                 tcp_ses->leaf_fullpath = kstrdup(ctx->leaf_fullpath, GFP_KERNEL);
1698                 if (!tcp_ses->leaf_fullpath) {
1699                         rc = -ENOMEM;
1700                         goto out_err;
1701                 }
1702         }
1703
1704         if (ctx->nosharesock)
1705                 tcp_ses->nosharesock = true;
1706
1707         tcp_ses->ops = ctx->ops;
1708         tcp_ses->vals = ctx->vals;
1709         cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1710
1711         tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1712         tcp_ses->noblockcnt = ctx->rootfs;
1713         tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1714         tcp_ses->noautotune = ctx->noautotune;
1715         tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1716         tcp_ses->rdma = ctx->rdma;
1717         tcp_ses->in_flight = 0;
1718         tcp_ses->max_in_flight = 0;
1719         tcp_ses->credits = 1;
1720         if (primary_server) {
1721                 spin_lock(&cifs_tcp_ses_lock);
1722                 ++primary_server->srv_count;
1723                 spin_unlock(&cifs_tcp_ses_lock);
1724                 tcp_ses->primary_server = primary_server;
1725         }
1726         init_waitqueue_head(&tcp_ses->response_q);
1727         init_waitqueue_head(&tcp_ses->request_q);
1728         INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1729         mutex_init(&tcp_ses->_srv_mutex);
1730         memcpy(tcp_ses->workstation_RFC1001_name,
1731                 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1732         memcpy(tcp_ses->server_RFC1001_name,
1733                 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1734         tcp_ses->session_estab = false;
1735         tcp_ses->sequence_number = 0;
1736         tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
1737         tcp_ses->reconnect_instance = 1;
1738         tcp_ses->lstrp = jiffies;
1739         tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1740         spin_lock_init(&tcp_ses->req_lock);
1741         spin_lock_init(&tcp_ses->srv_lock);
1742         spin_lock_init(&tcp_ses->mid_lock);
1743         INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1744         INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1745         INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1746         INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1747         mutex_init(&tcp_ses->reconnect_mutex);
1748 #ifdef CONFIG_CIFS_DFS_UPCALL
1749         mutex_init(&tcp_ses->refpath_lock);
1750 #endif
1751         memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1752                sizeof(tcp_ses->srcaddr));
1753         memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1754                 sizeof(tcp_ses->dstaddr));
1755         if (ctx->use_client_guid)
1756                 memcpy(tcp_ses->client_guid, ctx->client_guid,
1757                        SMB2_CLIENT_GUID_SIZE);
1758         else
1759                 generate_random_uuid(tcp_ses->client_guid);
1760         /*
1761          * at this point we are the only ones with the pointer
1762          * to the struct since the kernel thread not created yet
1763          * no need to spinlock this init of tcpStatus or srv_count
1764          */
1765         tcp_ses->tcpStatus = CifsNew;
1766         ++tcp_ses->srv_count;
1767
1768         if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1769                 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1770                 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1771         else
1772                 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1773         if (tcp_ses->rdma) {
1774 #ifndef CONFIG_CIFS_SMB_DIRECT
1775                 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1776                 rc = -ENOENT;
1777                 goto out_err_crypto_release;
1778 #endif
1779                 tcp_ses->smbd_conn = smbd_get_connection(
1780                         tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1781                 if (tcp_ses->smbd_conn) {
1782                         cifs_dbg(VFS, "RDMA transport established\n");
1783                         rc = 0;
1784                         goto smbd_connected;
1785                 } else {
1786                         rc = -ENOENT;
1787                         goto out_err_crypto_release;
1788                 }
1789         }
1790         rc = ip_connect(tcp_ses);
1791         if (rc < 0) {
1792                 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1793                 goto out_err_crypto_release;
1794         }
1795 smbd_connected:
1796         /*
1797          * since we're in a cifs function already, we know that
1798          * this will succeed. No need for try_module_get().
1799          */
1800         __module_get(THIS_MODULE);
1801         tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1802                                   tcp_ses, "cifsd");
1803         if (IS_ERR(tcp_ses->tsk)) {
1804                 rc = PTR_ERR(tcp_ses->tsk);
1805                 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1806                 module_put(THIS_MODULE);
1807                 goto out_err_crypto_release;
1808         }
1809         tcp_ses->min_offload = ctx->min_offload;
1810         tcp_ses->retrans = ctx->retrans;
1811         /*
1812          * at this point we are the only ones with the pointer
1813          * to the struct since the kernel thread not created yet
1814          * no need to spinlock this update of tcpStatus
1815          */
1816         spin_lock(&tcp_ses->srv_lock);
1817         tcp_ses->tcpStatus = CifsNeedNegotiate;
1818         spin_unlock(&tcp_ses->srv_lock);
1819
1820         if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1821                 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1822         else
1823                 tcp_ses->max_credits = ctx->max_credits;
1824
1825         tcp_ses->nr_targets = 1;
1826         tcp_ses->ignore_signature = ctx->ignore_signature;
1827         /* thread spawned, put it on the list */
1828         spin_lock(&cifs_tcp_ses_lock);
1829         list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1830         spin_unlock(&cifs_tcp_ses_lock);
1831
1832         /* queue echo request delayed work */
1833         queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1834
1835         return tcp_ses;
1836
1837 out_err_crypto_release:
1838         cifs_crypto_secmech_release(tcp_ses);
1839
1840         put_net(cifs_net_ns(tcp_ses));
1841
1842 out_err:
1843         if (tcp_ses) {
1844                 if (SERVER_IS_CHAN(tcp_ses))
1845                         cifs_put_tcp_session(tcp_ses->primary_server, false);
1846                 kfree(tcp_ses->hostname);
1847                 kfree(tcp_ses->leaf_fullpath);
1848                 if (tcp_ses->ssocket)
1849                         sock_release(tcp_ses->ssocket);
1850                 kfree(tcp_ses);
1851         }
1852         return ERR_PTR(rc);
1853 }
1854
1855 /* this function must be called with ses_lock and chan_lock held */
1856 static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1857 {
1858         if (ctx->sectype != Unspecified &&
1859             ctx->sectype != ses->sectype)
1860                 return 0;
1861
1862         /*
1863          * If an existing session is limited to less channels than
1864          * requested, it should not be reused
1865          */
1866         if (ses->chan_max < ctx->max_channels)
1867                 return 0;
1868
1869         switch (ses->sectype) {
1870         case Kerberos:
1871                 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1872                         return 0;
1873                 break;
1874         default:
1875                 /* NULL username means anonymous session */
1876                 if (ses->user_name == NULL) {
1877                         if (!ctx->nullauth)
1878                                 return 0;
1879                         break;
1880                 }
1881
1882                 /* anything else takes username/password */
1883                 if (strncmp(ses->user_name,
1884                             ctx->username ? ctx->username : "",
1885                             CIFS_MAX_USERNAME_LEN))
1886                         return 0;
1887                 if ((ctx->username && strlen(ctx->username) != 0) &&
1888                     ses->password != NULL &&
1889                     strncmp(ses->password,
1890                             ctx->password ? ctx->password : "",
1891                             CIFS_MAX_PASSWORD_LEN))
1892                         return 0;
1893         }
1894
1895         if (strcmp(ctx->local_nls->charset, ses->local_nls->charset))
1896                 return 0;
1897
1898         return 1;
1899 }
1900
1901 /**
1902  * cifs_setup_ipc - helper to setup the IPC tcon for the session
1903  * @ses: smb session to issue the request on
1904  * @ctx: the superblock configuration context to use for building the
1905  *       new tree connection for the IPC (interprocess communication RPC)
1906  *
1907  * A new IPC connection is made and stored in the session
1908  * tcon_ipc. The IPC tcon has the same lifetime as the session.
1909  */
1910 static int
1911 cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1912 {
1913         int rc = 0, xid;
1914         struct cifs_tcon *tcon;
1915         char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1916         bool seal = false;
1917         struct TCP_Server_Info *server = ses->server;
1918
1919         /*
1920          * If the mount request that resulted in the creation of the
1921          * session requires encryption, force IPC to be encrypted too.
1922          */
1923         if (ctx->seal) {
1924                 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1925                         seal = true;
1926                 else {
1927                         cifs_server_dbg(VFS,
1928                                  "IPC: server doesn't support encryption\n");
1929                         return -EOPNOTSUPP;
1930                 }
1931         }
1932
1933         /* no need to setup directory caching on IPC share, so pass in false */
1934         tcon = tcon_info_alloc(false);
1935         if (tcon == NULL)
1936                 return -ENOMEM;
1937
1938         spin_lock(&server->srv_lock);
1939         scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1940         spin_unlock(&server->srv_lock);
1941
1942         xid = get_xid();
1943         tcon->ses = ses;
1944         tcon->ipc = true;
1945         tcon->seal = seal;
1946         rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1947         free_xid(xid);
1948
1949         if (rc) {
1950                 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1951                 tconInfoFree(tcon);
1952                 goto out;
1953         }
1954
1955         cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
1956
1957         spin_lock(&tcon->tc_lock);
1958         tcon->status = TID_GOOD;
1959         spin_unlock(&tcon->tc_lock);
1960         ses->tcon_ipc = tcon;
1961 out:
1962         return rc;
1963 }
1964
1965 /**
1966  * cifs_free_ipc - helper to release the session IPC tcon
1967  * @ses: smb session to unmount the IPC from
1968  *
1969  * Needs to be called everytime a session is destroyed.
1970  *
1971  * On session close, the IPC is closed and the server must release all tcons of the session.
1972  * No need to send a tree disconnect here.
1973  *
1974  * Besides, it will make the server to not close durable and resilient files on session close, as
1975  * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1976  */
1977 static int
1978 cifs_free_ipc(struct cifs_ses *ses)
1979 {
1980         struct cifs_tcon *tcon = ses->tcon_ipc;
1981
1982         if (tcon == NULL)
1983                 return 0;
1984
1985         tconInfoFree(tcon);
1986         ses->tcon_ipc = NULL;
1987         return 0;
1988 }
1989
1990 static struct cifs_ses *
1991 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1992 {
1993         struct cifs_ses *ses, *ret = NULL;
1994
1995         spin_lock(&cifs_tcp_ses_lock);
1996         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1997                 spin_lock(&ses->ses_lock);
1998                 if (ses->ses_status == SES_EXITING) {
1999                         spin_unlock(&ses->ses_lock);
2000                         continue;
2001                 }
2002                 spin_lock(&ses->chan_lock);
2003                 if (match_session(ses, ctx)) {
2004                         spin_unlock(&ses->chan_lock);
2005                         spin_unlock(&ses->ses_lock);
2006                         ret = ses;
2007                         break;
2008                 }
2009                 spin_unlock(&ses->chan_lock);
2010                 spin_unlock(&ses->ses_lock);
2011         }
2012         if (ret)
2013                 cifs_smb_ses_inc_refcount(ret);
2014         spin_unlock(&cifs_tcp_ses_lock);
2015         return ret;
2016 }
2017
2018 void __cifs_put_smb_ses(struct cifs_ses *ses)
2019 {
2020         struct TCP_Server_Info *server = ses->server;
2021         unsigned int xid;
2022         size_t i;
2023         int rc;
2024
2025         spin_lock(&ses->ses_lock);
2026         if (ses->ses_status == SES_EXITING) {
2027                 spin_unlock(&ses->ses_lock);
2028                 return;
2029         }
2030         spin_unlock(&ses->ses_lock);
2031
2032         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
2033         cifs_dbg(FYI,
2034                  "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
2035
2036         spin_lock(&cifs_tcp_ses_lock);
2037         if (--ses->ses_count > 0) {
2038                 spin_unlock(&cifs_tcp_ses_lock);
2039                 return;
2040         }
2041         spin_lock(&ses->ses_lock);
2042         if (ses->ses_status == SES_GOOD)
2043                 ses->ses_status = SES_EXITING;
2044         spin_unlock(&ses->ses_lock);
2045         spin_unlock(&cifs_tcp_ses_lock);
2046
2047         /* ses_count can never go negative */
2048         WARN_ON(ses->ses_count < 0);
2049
2050         spin_lock(&ses->ses_lock);
2051         if (ses->ses_status == SES_EXITING && server->ops->logoff) {
2052                 spin_unlock(&ses->ses_lock);
2053                 cifs_free_ipc(ses);
2054                 xid = get_xid();
2055                 rc = server->ops->logoff(xid, ses);
2056                 if (rc)
2057                         cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
2058                                 __func__, rc);
2059                 _free_xid(xid);
2060         } else {
2061                 spin_unlock(&ses->ses_lock);
2062                 cifs_free_ipc(ses);
2063         }
2064
2065         spin_lock(&cifs_tcp_ses_lock);
2066         list_del_init(&ses->smb_ses_list);
2067         spin_unlock(&cifs_tcp_ses_lock);
2068
2069         /* close any extra channels */
2070         for (i = 1; i < ses->chan_count; i++) {
2071                 if (ses->chans[i].iface) {
2072                         kref_put(&ses->chans[i].iface->refcount, release_iface);
2073                         ses->chans[i].iface = NULL;
2074                 }
2075                 cifs_put_tcp_session(ses->chans[i].server, 0);
2076                 ses->chans[i].server = NULL;
2077         }
2078
2079         /* we now account for primary channel in iface->refcount */
2080         if (ses->chans[0].iface) {
2081                 kref_put(&ses->chans[0].iface->refcount, release_iface);
2082                 ses->chans[0].server = NULL;
2083         }
2084
2085         sesInfoFree(ses);
2086         cifs_put_tcp_session(server, 0);
2087 }
2088
2089 #ifdef CONFIG_KEYS
2090
2091 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
2092 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
2093
2094 /* Populate username and pw fields from keyring if possible */
2095 static int
2096 cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
2097 {
2098         int rc = 0;
2099         int is_domain = 0;
2100         const char *delim, *payload;
2101         char *desc;
2102         ssize_t len;
2103         struct key *key;
2104         struct TCP_Server_Info *server = ses->server;
2105         struct sockaddr_in *sa;
2106         struct sockaddr_in6 *sa6;
2107         const struct user_key_payload *upayload;
2108
2109         desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
2110         if (!desc)
2111                 return -ENOMEM;
2112
2113         /* try to find an address key first */
2114         switch (server->dstaddr.ss_family) {
2115         case AF_INET:
2116                 sa = (struct sockaddr_in *)&server->dstaddr;
2117                 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
2118                 break;
2119         case AF_INET6:
2120                 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
2121                 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
2122                 break;
2123         default:
2124                 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
2125                          server->dstaddr.ss_family);
2126                 rc = -EINVAL;
2127                 goto out_err;
2128         }
2129
2130         cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2131         key = request_key(&key_type_logon, desc, "");
2132         if (IS_ERR(key)) {
2133                 if (!ses->domainName) {
2134                         cifs_dbg(FYI, "domainName is NULL\n");
2135                         rc = PTR_ERR(key);
2136                         goto out_err;
2137                 }
2138
2139                 /* didn't work, try to find a domain key */
2140                 sprintf(desc, "cifs:d:%s", ses->domainName);
2141                 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2142                 key = request_key(&key_type_logon, desc, "");
2143                 if (IS_ERR(key)) {
2144                         rc = PTR_ERR(key);
2145                         goto out_err;
2146                 }
2147                 is_domain = 1;
2148         }
2149
2150         down_read(&key->sem);
2151         upayload = user_key_payload_locked(key);
2152         if (IS_ERR_OR_NULL(upayload)) {
2153                 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
2154                 goto out_key_put;
2155         }
2156
2157         /* find first : in payload */
2158         payload = upayload->data;
2159         delim = strnchr(payload, upayload->datalen, ':');
2160         cifs_dbg(FYI, "payload=%s\n", payload);
2161         if (!delim) {
2162                 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
2163                          upayload->datalen);
2164                 rc = -EINVAL;
2165                 goto out_key_put;
2166         }
2167
2168         len = delim - payload;
2169         if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
2170                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
2171                          len);
2172                 rc = -EINVAL;
2173                 goto out_key_put;
2174         }
2175
2176         ctx->username = kstrndup(payload, len, GFP_KERNEL);
2177         if (!ctx->username) {
2178                 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
2179                          len);
2180                 rc = -ENOMEM;
2181                 goto out_key_put;
2182         }
2183         cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
2184
2185         len = key->datalen - (len + 1);
2186         if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
2187                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
2188                 rc = -EINVAL;
2189                 kfree(ctx->username);
2190                 ctx->username = NULL;
2191                 goto out_key_put;
2192         }
2193
2194         ++delim;
2195         ctx->password = kstrndup(delim, len, GFP_KERNEL);
2196         if (!ctx->password) {
2197                 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
2198                          len);
2199                 rc = -ENOMEM;
2200                 kfree(ctx->username);
2201                 ctx->username = NULL;
2202                 goto out_key_put;
2203         }
2204
2205         /*
2206          * If we have a domain key then we must set the domainName in the
2207          * for the request.
2208          */
2209         if (is_domain && ses->domainName) {
2210                 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
2211                 if (!ctx->domainname) {
2212                         cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
2213                                  len);
2214                         rc = -ENOMEM;
2215                         kfree(ctx->username);
2216                         ctx->username = NULL;
2217                         kfree_sensitive(ctx->password);
2218                         ctx->password = NULL;
2219                         goto out_key_put;
2220                 }
2221         }
2222
2223         strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
2224
2225 out_key_put:
2226         up_read(&key->sem);
2227         key_put(key);
2228 out_err:
2229         kfree(desc);
2230         cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
2231         return rc;
2232 }
2233 #else /* ! CONFIG_KEYS */
2234 static inline int
2235 cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
2236                    struct cifs_ses *ses __attribute__((unused)))
2237 {
2238         return -ENOSYS;
2239 }
2240 #endif /* CONFIG_KEYS */
2241
2242 /**
2243  * cifs_get_smb_ses - get a session matching @ctx data from @server
2244  * @server: server to setup the session to
2245  * @ctx: superblock configuration context to use to setup the session
2246  *
2247  * This function assumes it is being called from cifs_mount() where we
2248  * already got a server reference (server refcount +1). See
2249  * cifs_get_tcon() for refcount explanations.
2250  */
2251 struct cifs_ses *
2252 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
2253 {
2254         int rc = 0;
2255         unsigned int xid;
2256         struct cifs_ses *ses;
2257         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2258         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2259
2260         xid = get_xid();
2261
2262         ses = cifs_find_smb_ses(server, ctx);
2263         if (ses) {
2264                 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
2265                          ses->ses_status);
2266
2267                 spin_lock(&ses->chan_lock);
2268                 if (cifs_chan_needs_reconnect(ses, server)) {
2269                         spin_unlock(&ses->chan_lock);
2270                         cifs_dbg(FYI, "Session needs reconnect\n");
2271
2272                         mutex_lock(&ses->session_mutex);
2273                         rc = cifs_negotiate_protocol(xid, ses, server);
2274                         if (rc) {
2275                                 mutex_unlock(&ses->session_mutex);
2276                                 /* problem -- put our ses reference */
2277                                 cifs_put_smb_ses(ses);
2278                                 free_xid(xid);
2279                                 return ERR_PTR(rc);
2280                         }
2281
2282                         rc = cifs_setup_session(xid, ses, server,
2283                                                 ctx->local_nls);
2284                         if (rc) {
2285                                 mutex_unlock(&ses->session_mutex);
2286                                 /* problem -- put our reference */
2287                                 cifs_put_smb_ses(ses);
2288                                 free_xid(xid);
2289                                 return ERR_PTR(rc);
2290                         }
2291                         mutex_unlock(&ses->session_mutex);
2292
2293                         spin_lock(&ses->chan_lock);
2294                 }
2295                 spin_unlock(&ses->chan_lock);
2296
2297                 /* existing SMB ses has a server reference already */
2298                 cifs_put_tcp_session(server, 0);
2299                 free_xid(xid);
2300                 return ses;
2301         }
2302
2303         rc = -ENOMEM;
2304
2305         cifs_dbg(FYI, "Existing smb sess not found\n");
2306         ses = sesInfoAlloc();
2307         if (ses == NULL)
2308                 goto get_ses_fail;
2309
2310         /* new SMB session uses our server ref */
2311         ses->server = server;
2312         if (server->dstaddr.ss_family == AF_INET6)
2313                 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
2314         else
2315                 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
2316
2317         if (ctx->username) {
2318                 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
2319                 if (!ses->user_name)
2320                         goto get_ses_fail;
2321         }
2322
2323         /* ctx->password freed at unmount */
2324         if (ctx->password) {
2325                 ses->password = kstrdup(ctx->password, GFP_KERNEL);
2326                 if (!ses->password)
2327                         goto get_ses_fail;
2328         }
2329         if (ctx->domainname) {
2330                 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
2331                 if (!ses->domainName)
2332                         goto get_ses_fail;
2333         }
2334
2335         strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
2336
2337         if (ctx->domainauto)
2338                 ses->domainAuto = ctx->domainauto;
2339         ses->cred_uid = ctx->cred_uid;
2340         ses->linux_uid = ctx->linux_uid;
2341
2342         ses->sectype = ctx->sectype;
2343         ses->sign = ctx->sign;
2344         ses->local_nls = load_nls(ctx->local_nls->charset);
2345
2346         /* add server as first channel */
2347         spin_lock(&ses->chan_lock);
2348         ses->chans[0].server = server;
2349         ses->chan_count = 1;
2350         ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
2351         ses->chans_need_reconnect = 1;
2352         spin_unlock(&ses->chan_lock);
2353
2354         mutex_lock(&ses->session_mutex);
2355         rc = cifs_negotiate_protocol(xid, ses, server);
2356         if (!rc)
2357                 rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
2358         mutex_unlock(&ses->session_mutex);
2359
2360         /* each channel uses a different signing key */
2361         spin_lock(&ses->chan_lock);
2362         memcpy(ses->chans[0].signkey, ses->smb3signingkey,
2363                sizeof(ses->smb3signingkey));
2364         spin_unlock(&ses->chan_lock);
2365
2366         if (rc)
2367                 goto get_ses_fail;
2368
2369         /*
2370          * success, put it on the list and add it as first channel
2371          * note: the session becomes active soon after this. So you'll
2372          * need to lock before changing something in the session.
2373          */
2374         spin_lock(&cifs_tcp_ses_lock);
2375         ses->dfs_root_ses = ctx->dfs_root_ses;
2376         if (ses->dfs_root_ses)
2377                 ses->dfs_root_ses->ses_count++;
2378         list_add(&ses->smb_ses_list, &server->smb_ses_list);
2379         spin_unlock(&cifs_tcp_ses_lock);
2380
2381         cifs_setup_ipc(ses, ctx);
2382
2383         free_xid(xid);
2384
2385         return ses;
2386
2387 get_ses_fail:
2388         sesInfoFree(ses);
2389         free_xid(xid);
2390         return ERR_PTR(rc);
2391 }
2392
2393 /* this function must be called with tc_lock held */
2394 static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
2395 {
2396         struct TCP_Server_Info *server = tcon->ses->server;
2397
2398         if (tcon->status == TID_EXITING)
2399                 return 0;
2400
2401         if (tcon->origin_fullpath) {
2402                 if (!ctx->source ||
2403                     !dfs_src_pathname_equal(ctx->source,
2404                                             tcon->origin_fullpath))
2405                         return 0;
2406         } else if (!server->leaf_fullpath &&
2407                    strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE)) {
2408                 return 0;
2409         }
2410         if (tcon->seal != ctx->seal)
2411                 return 0;
2412         if (tcon->snapshot_time != ctx->snapshot_time)
2413                 return 0;
2414         if (tcon->handle_timeout != ctx->handle_timeout)
2415                 return 0;
2416         if (tcon->no_lease != ctx->no_lease)
2417                 return 0;
2418         if (tcon->nodelete != ctx->nodelete)
2419                 return 0;
2420         return 1;
2421 }
2422
2423 static struct cifs_tcon *
2424 cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2425 {
2426         struct cifs_tcon *tcon;
2427
2428         spin_lock(&cifs_tcp_ses_lock);
2429         list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
2430                 spin_lock(&tcon->tc_lock);
2431                 if (!match_tcon(tcon, ctx)) {
2432                         spin_unlock(&tcon->tc_lock);
2433                         continue;
2434                 }
2435                 ++tcon->tc_count;
2436                 spin_unlock(&tcon->tc_lock);
2437                 spin_unlock(&cifs_tcp_ses_lock);
2438                 return tcon;
2439         }
2440         spin_unlock(&cifs_tcp_ses_lock);
2441         return NULL;
2442 }
2443
2444 void
2445 cifs_put_tcon(struct cifs_tcon *tcon)
2446 {
2447         unsigned int xid;
2448         struct cifs_ses *ses;
2449
2450         /*
2451          * IPC tcon share the lifetime of their session and are
2452          * destroyed in the session put function
2453          */
2454         if (tcon == NULL || tcon->ipc)
2455                 return;
2456
2457         ses = tcon->ses;
2458         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2459         spin_lock(&cifs_tcp_ses_lock);
2460         spin_lock(&tcon->tc_lock);
2461         if (--tcon->tc_count > 0) {
2462                 spin_unlock(&tcon->tc_lock);
2463                 spin_unlock(&cifs_tcp_ses_lock);
2464                 return;
2465         }
2466
2467         /* tc_count can never go negative */
2468         WARN_ON(tcon->tc_count < 0);
2469
2470         list_del_init(&tcon->tcon_list);
2471         tcon->status = TID_EXITING;
2472         spin_unlock(&tcon->tc_lock);
2473         spin_unlock(&cifs_tcp_ses_lock);
2474
2475         /* cancel polling of interfaces */
2476         cancel_delayed_work_sync(&tcon->query_interfaces);
2477 #ifdef CONFIG_CIFS_DFS_UPCALL
2478         cancel_delayed_work_sync(&tcon->dfs_cache_work);
2479 #endif
2480
2481         if (tcon->use_witness) {
2482                 int rc;
2483
2484                 rc = cifs_swn_unregister(tcon);
2485                 if (rc < 0) {
2486                         cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2487                                         __func__, rc);
2488                 }
2489         }
2490
2491         xid = get_xid();
2492         if (ses->server->ops->tree_disconnect)
2493                 ses->server->ops->tree_disconnect(xid, tcon);
2494         _free_xid(xid);
2495
2496         cifs_fscache_release_super_cookie(tcon);
2497         tconInfoFree(tcon);
2498         cifs_put_smb_ses(ses);
2499 }
2500
2501 /**
2502  * cifs_get_tcon - get a tcon matching @ctx data from @ses
2503  * @ses: smb session to issue the request on
2504  * @ctx: the superblock configuration context to use for building the
2505  *
2506  * - tcon refcount is the number of mount points using the tcon.
2507  * - ses refcount is the number of tcon using the session.
2508  *
2509  * 1. This function assumes it is being called from cifs_mount() where
2510  *    we already got a session reference (ses refcount +1).
2511  *
2512  * 2. Since we're in the context of adding a mount point, the end
2513  *    result should be either:
2514  *
2515  * a) a new tcon already allocated with refcount=1 (1 mount point) and
2516  *    its session refcount incremented (1 new tcon). This +1 was
2517  *    already done in (1).
2518  *
2519  * b) an existing tcon with refcount+1 (add a mount point to it) and
2520  *    identical ses refcount (no new tcon). Because of (1) we need to
2521  *    decrement the ses refcount.
2522  */
2523 static struct cifs_tcon *
2524 cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2525 {
2526         struct cifs_tcon *tcon;
2527         bool nohandlecache;
2528         int rc, xid;
2529
2530         tcon = cifs_find_tcon(ses, ctx);
2531         if (tcon) {
2532                 /*
2533                  * tcon has refcount already incremented but we need to
2534                  * decrement extra ses reference gotten by caller (case b)
2535                  */
2536                 cifs_dbg(FYI, "Found match on UNC path\n");
2537                 cifs_put_smb_ses(ses);
2538                 return tcon;
2539         }
2540
2541         if (!ses->server->ops->tree_connect) {
2542                 rc = -ENOSYS;
2543                 goto out_fail;
2544         }
2545
2546         if (ses->server->dialect >= SMB20_PROT_ID &&
2547             (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING))
2548                 nohandlecache = ctx->nohandlecache;
2549         else
2550                 nohandlecache = true;
2551         tcon = tcon_info_alloc(!nohandlecache);
2552         if (tcon == NULL) {
2553                 rc = -ENOMEM;
2554                 goto out_fail;
2555         }
2556         tcon->nohandlecache = nohandlecache;
2557
2558         if (ctx->snapshot_time) {
2559                 if (ses->server->vals->protocol_id == 0) {
2560                         cifs_dbg(VFS,
2561                              "Use SMB2 or later for snapshot mount option\n");
2562                         rc = -EOPNOTSUPP;
2563                         goto out_fail;
2564                 } else
2565                         tcon->snapshot_time = ctx->snapshot_time;
2566         }
2567
2568         if (ctx->handle_timeout) {
2569                 if (ses->server->vals->protocol_id == 0) {
2570                         cifs_dbg(VFS,
2571                              "Use SMB2.1 or later for handle timeout option\n");
2572                         rc = -EOPNOTSUPP;
2573                         goto out_fail;
2574                 } else
2575                         tcon->handle_timeout = ctx->handle_timeout;
2576         }
2577
2578         tcon->ses = ses;
2579         if (ctx->password) {
2580                 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2581                 if (!tcon->password) {
2582                         rc = -ENOMEM;
2583                         goto out_fail;
2584                 }
2585         }
2586
2587         if (ctx->seal) {
2588                 if (ses->server->vals->protocol_id == 0) {
2589                         cifs_dbg(VFS,
2590                                  "SMB3 or later required for encryption\n");
2591                         rc = -EOPNOTSUPP;
2592                         goto out_fail;
2593                 } else if (tcon->ses->server->capabilities &
2594                                         SMB2_GLOBAL_CAP_ENCRYPTION)
2595                         tcon->seal = true;
2596                 else {
2597                         cifs_dbg(VFS, "Encryption is not supported on share\n");
2598                         rc = -EOPNOTSUPP;
2599                         goto out_fail;
2600                 }
2601         }
2602
2603         if (ctx->linux_ext) {
2604                 if (ses->server->posix_ext_supported) {
2605                         tcon->posix_extensions = true;
2606                         pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2607                 } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
2608                     (strcmp(ses->server->vals->version_string,
2609                      SMB3ANY_VERSION_STRING) == 0) ||
2610                     (strcmp(ses->server->vals->version_string,
2611                      SMBDEFAULT_VERSION_STRING) == 0)) {
2612                         cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2613                         rc = -EOPNOTSUPP;
2614                         goto out_fail;
2615                 } else {
2616                         cifs_dbg(VFS,
2617                                 "Check vers= mount option. SMB3.11 disabled but required for POSIX extensions\n");
2618                         rc = -EOPNOTSUPP;
2619                         goto out_fail;
2620                 }
2621         }
2622
2623         xid = get_xid();
2624         rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2625                                             ctx->local_nls);
2626         free_xid(xid);
2627         cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2628         if (rc)
2629                 goto out_fail;
2630
2631         tcon->use_persistent = false;
2632         /* check if SMB2 or later, CIFS does not support persistent handles */
2633         if (ctx->persistent) {
2634                 if (ses->server->vals->protocol_id == 0) {
2635                         cifs_dbg(VFS,
2636                              "SMB3 or later required for persistent handles\n");
2637                         rc = -EOPNOTSUPP;
2638                         goto out_fail;
2639                 } else if (ses->server->capabilities &
2640                            SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2641                         tcon->use_persistent = true;
2642                 else /* persistent handles requested but not supported */ {
2643                         cifs_dbg(VFS,
2644                                 "Persistent handles not supported on share\n");
2645                         rc = -EOPNOTSUPP;
2646                         goto out_fail;
2647                 }
2648         } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2649              && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2650              && (ctx->nopersistent == false)) {
2651                 cifs_dbg(FYI, "enabling persistent handles\n");
2652                 tcon->use_persistent = true;
2653         } else if (ctx->resilient) {
2654                 if (ses->server->vals->protocol_id == 0) {
2655                         cifs_dbg(VFS,
2656                              "SMB2.1 or later required for resilient handles\n");
2657                         rc = -EOPNOTSUPP;
2658                         goto out_fail;
2659                 }
2660                 tcon->use_resilient = true;
2661         }
2662
2663         tcon->use_witness = false;
2664         if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2665                 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2666                         if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2667                                 /*
2668                                  * Set witness in use flag in first place
2669                                  * to retry registration in the echo task
2670                                  */
2671                                 tcon->use_witness = true;
2672                                 /* And try to register immediately */
2673                                 rc = cifs_swn_register(tcon);
2674                                 if (rc < 0) {
2675                                         cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2676                                         goto out_fail;
2677                                 }
2678                         } else {
2679                                 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2680                                 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2681                                 rc = -EOPNOTSUPP;
2682                                 goto out_fail;
2683                         }
2684                 } else {
2685                         cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2686                         rc = -EOPNOTSUPP;
2687                         goto out_fail;
2688                 }
2689         }
2690
2691         /* If the user really knows what they are doing they can override */
2692         if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2693                 if (ctx->cache_ro)
2694                         cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2695                 else if (ctx->cache_rw)
2696                         cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2697         }
2698
2699         if (ctx->no_lease) {
2700                 if (ses->server->vals->protocol_id == 0) {
2701                         cifs_dbg(VFS,
2702                                 "SMB2 or later required for nolease option\n");
2703                         rc = -EOPNOTSUPP;
2704                         goto out_fail;
2705                 } else
2706                         tcon->no_lease = ctx->no_lease;
2707         }
2708
2709         /*
2710          * We can have only one retry value for a connection to a share so for
2711          * resources mounted more than once to the same server share the last
2712          * value passed in for the retry flag is used.
2713          */
2714         tcon->retry = ctx->retry;
2715         tcon->nocase = ctx->nocase;
2716         tcon->broken_sparse_sup = ctx->no_sparse;
2717         tcon->max_cached_dirs = ctx->max_cached_dirs;
2718         tcon->nodelete = ctx->nodelete;
2719         tcon->local_lease = ctx->local_lease;
2720         INIT_LIST_HEAD(&tcon->pending_opens);
2721         tcon->status = TID_GOOD;
2722
2723         INIT_DELAYED_WORK(&tcon->query_interfaces,
2724                           smb2_query_server_interfaces);
2725         if (ses->server->dialect >= SMB30_PROT_ID &&
2726             (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
2727                 /* schedule query interfaces poll */
2728                 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
2729                                    (SMB_INTERFACE_POLL_INTERVAL * HZ));
2730         }
2731 #ifdef CONFIG_CIFS_DFS_UPCALL
2732         INIT_DELAYED_WORK(&tcon->dfs_cache_work, dfs_cache_refresh);
2733 #endif
2734         spin_lock(&cifs_tcp_ses_lock);
2735         list_add(&tcon->tcon_list, &ses->tcon_list);
2736         spin_unlock(&cifs_tcp_ses_lock);
2737
2738         return tcon;
2739
2740 out_fail:
2741         tconInfoFree(tcon);
2742         return ERR_PTR(rc);
2743 }
2744
2745 void
2746 cifs_put_tlink(struct tcon_link *tlink)
2747 {
2748         if (!tlink || IS_ERR(tlink))
2749                 return;
2750
2751         if (!atomic_dec_and_test(&tlink->tl_count) ||
2752             test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2753                 tlink->tl_time = jiffies;
2754                 return;
2755         }
2756
2757         if (!IS_ERR(tlink_tcon(tlink)))
2758                 cifs_put_tcon(tlink_tcon(tlink));
2759         kfree(tlink);
2760 }
2761
2762 static int
2763 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2764 {
2765         struct cifs_sb_info *old = CIFS_SB(sb);
2766         struct cifs_sb_info *new = mnt_data->cifs_sb;
2767         unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2768         unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2769
2770         if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2771                 return 0;
2772
2773         if (old->mnt_cifs_serverino_autodisabled)
2774                 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2775
2776         if (oldflags != newflags)
2777                 return 0;
2778
2779         /*
2780          * We want to share sb only if we don't specify an r/wsize or
2781          * specified r/wsize is greater than or equal to existing one.
2782          */
2783         if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2784                 return 0;
2785
2786         if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2787                 return 0;
2788
2789         if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2790             !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2791                 return 0;
2792
2793         if (old->ctx->file_mode != new->ctx->file_mode ||
2794             old->ctx->dir_mode != new->ctx->dir_mode)
2795                 return 0;
2796
2797         if (strcmp(old->local_nls->charset, new->local_nls->charset))
2798                 return 0;
2799
2800         if (old->ctx->acregmax != new->ctx->acregmax)
2801                 return 0;
2802         if (old->ctx->acdirmax != new->ctx->acdirmax)
2803                 return 0;
2804         if (old->ctx->closetimeo != new->ctx->closetimeo)
2805                 return 0;
2806
2807         return 1;
2808 }
2809
2810 static int match_prepath(struct super_block *sb,
2811                          struct cifs_tcon *tcon,
2812                          struct cifs_mnt_data *mnt_data)
2813 {
2814         struct smb3_fs_context *ctx = mnt_data->ctx;
2815         struct cifs_sb_info *old = CIFS_SB(sb);
2816         struct cifs_sb_info *new = mnt_data->cifs_sb;
2817         bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2818                 old->prepath;
2819         bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2820                 new->prepath;
2821
2822         if (tcon->origin_fullpath &&
2823             dfs_src_pathname_equal(tcon->origin_fullpath, ctx->source))
2824                 return 1;
2825
2826         if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2827                 return 1;
2828         else if (!old_set && !new_set)
2829                 return 1;
2830
2831         return 0;
2832 }
2833
2834 int
2835 cifs_match_super(struct super_block *sb, void *data)
2836 {
2837         struct cifs_mnt_data *mnt_data = data;
2838         struct smb3_fs_context *ctx;
2839         struct cifs_sb_info *cifs_sb;
2840         struct TCP_Server_Info *tcp_srv;
2841         struct cifs_ses *ses;
2842         struct cifs_tcon *tcon;
2843         struct tcon_link *tlink;
2844         int rc = 0;
2845
2846         spin_lock(&cifs_tcp_ses_lock);
2847         cifs_sb = CIFS_SB(sb);
2848
2849         /* We do not want to use a superblock that has been shutdown */
2850         if (CIFS_MOUNT_SHUTDOWN & cifs_sb->mnt_cifs_flags) {
2851                 spin_unlock(&cifs_tcp_ses_lock);
2852                 return 0;
2853         }
2854
2855         tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2856         if (IS_ERR_OR_NULL(tlink)) {
2857                 pr_warn_once("%s: skip super matching due to bad tlink(%p)\n",
2858                              __func__, tlink);
2859                 spin_unlock(&cifs_tcp_ses_lock);
2860                 return 0;
2861         }
2862         tcon = tlink_tcon(tlink);
2863         ses = tcon->ses;
2864         tcp_srv = ses->server;
2865
2866         ctx = mnt_data->ctx;
2867
2868         spin_lock(&tcp_srv->srv_lock);
2869         spin_lock(&ses->ses_lock);
2870         spin_lock(&ses->chan_lock);
2871         spin_lock(&tcon->tc_lock);
2872         if (!match_server(tcp_srv, ctx, true) ||
2873             !match_session(ses, ctx) ||
2874             !match_tcon(tcon, ctx) ||
2875             !match_prepath(sb, tcon, mnt_data)) {
2876                 rc = 0;
2877                 goto out;
2878         }
2879
2880         rc = compare_mount_options(sb, mnt_data);
2881 out:
2882         spin_unlock(&tcon->tc_lock);
2883         spin_unlock(&ses->chan_lock);
2884         spin_unlock(&ses->ses_lock);
2885         spin_unlock(&tcp_srv->srv_lock);
2886
2887         spin_unlock(&cifs_tcp_ses_lock);
2888         cifs_put_tlink(tlink);
2889         return rc;
2890 }
2891
2892 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2893 static struct lock_class_key cifs_key[2];
2894 static struct lock_class_key cifs_slock_key[2];
2895
2896 static inline void
2897 cifs_reclassify_socket4(struct socket *sock)
2898 {
2899         struct sock *sk = sock->sk;
2900
2901         BUG_ON(!sock_allow_reclassification(sk));
2902         sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2903                 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2904 }
2905
2906 static inline void
2907 cifs_reclassify_socket6(struct socket *sock)
2908 {
2909         struct sock *sk = sock->sk;
2910
2911         BUG_ON(!sock_allow_reclassification(sk));
2912         sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2913                 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2914 }
2915 #else
2916 static inline void
2917 cifs_reclassify_socket4(struct socket *sock)
2918 {
2919 }
2920
2921 static inline void
2922 cifs_reclassify_socket6(struct socket *sock)
2923 {
2924 }
2925 #endif
2926
2927 /* See RFC1001 section 14 on representation of Netbios names */
2928 static void rfc1002mangle(char *target, char *source, unsigned int length)
2929 {
2930         unsigned int i, j;
2931
2932         for (i = 0, j = 0; i < (length); i++) {
2933                 /* mask a nibble at a time and encode */
2934                 target[j] = 'A' + (0x0F & (source[i] >> 4));
2935                 target[j+1] = 'A' + (0x0F & source[i]);
2936                 j += 2;
2937         }
2938
2939 }
2940
2941 static int
2942 bind_socket(struct TCP_Server_Info *server)
2943 {
2944         int rc = 0;
2945
2946         if (server->srcaddr.ss_family != AF_UNSPEC) {
2947                 /* Bind to the specified local IP address */
2948                 struct socket *socket = server->ssocket;
2949
2950                 rc = kernel_bind(socket,
2951                                  (struct sockaddr *) &server->srcaddr,
2952                                  sizeof(server->srcaddr));
2953                 if (rc < 0) {
2954                         struct sockaddr_in *saddr4;
2955                         struct sockaddr_in6 *saddr6;
2956
2957                         saddr4 = (struct sockaddr_in *)&server->srcaddr;
2958                         saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2959                         if (saddr6->sin6_family == AF_INET6)
2960                                 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2961                                          &saddr6->sin6_addr, rc);
2962                         else
2963                                 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2964                                          &saddr4->sin_addr.s_addr, rc);
2965                 }
2966         }
2967         return rc;
2968 }
2969
2970 static int
2971 ip_rfc1001_connect(struct TCP_Server_Info *server)
2972 {
2973         int rc = 0;
2974         /*
2975          * some servers require RFC1001 sessinit before sending
2976          * negprot - BB check reconnection in case where second
2977          * sessinit is sent but no second negprot
2978          */
2979         struct rfc1002_session_packet req = {};
2980         struct smb_hdr *smb_buf = (struct smb_hdr *)&req;
2981         unsigned int len;
2982
2983         req.trailer.session_req.called_len = sizeof(req.trailer.session_req.called_name);
2984
2985         if (server->server_RFC1001_name[0] != 0)
2986                 rfc1002mangle(req.trailer.session_req.called_name,
2987                               server->server_RFC1001_name,
2988                               RFC1001_NAME_LEN_WITH_NULL);
2989         else
2990                 rfc1002mangle(req.trailer.session_req.called_name,
2991                               DEFAULT_CIFS_CALLED_NAME,
2992                               RFC1001_NAME_LEN_WITH_NULL);
2993
2994         req.trailer.session_req.calling_len = sizeof(req.trailer.session_req.calling_name);
2995
2996         /* calling name ends in null (byte 16) from old smb convention */
2997         if (server->workstation_RFC1001_name[0] != 0)
2998                 rfc1002mangle(req.trailer.session_req.calling_name,
2999                               server->workstation_RFC1001_name,
3000                               RFC1001_NAME_LEN_WITH_NULL);
3001         else
3002                 rfc1002mangle(req.trailer.session_req.calling_name,
3003                               "LINUX_CIFS_CLNT",
3004                               RFC1001_NAME_LEN_WITH_NULL);
3005
3006         /*
3007          * As per rfc1002, @len must be the number of bytes that follows the
3008          * length field of a rfc1002 session request payload.
3009          */
3010         len = sizeof(req) - offsetof(struct rfc1002_session_packet, trailer.session_req);
3011
3012         smb_buf->smb_buf_length = cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | len);
3013         rc = smb_send(server, smb_buf, len);
3014         /*
3015          * RFC1001 layer in at least one server requires very short break before
3016          * negprot presumably because not expecting negprot to follow so fast.
3017          * This is a simple solution that works without complicating the code
3018          * and causes no significant slowing down on mount for everyone else
3019          */
3020         usleep_range(1000, 2000);
3021
3022         return rc;
3023 }
3024
3025 static int
3026 generic_ip_connect(struct TCP_Server_Info *server)
3027 {
3028         struct sockaddr *saddr;
3029         struct socket *socket;
3030         int slen, sfamily;
3031         __be16 sport;
3032         int rc = 0;
3033
3034         saddr = (struct sockaddr *) &server->dstaddr;
3035
3036         if (server->dstaddr.ss_family == AF_INET6) {
3037                 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
3038
3039                 sport = ipv6->sin6_port;
3040                 slen = sizeof(struct sockaddr_in6);
3041                 sfamily = AF_INET6;
3042                 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
3043                                 ntohs(sport));
3044         } else {
3045                 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
3046
3047                 sport = ipv4->sin_port;
3048                 slen = sizeof(struct sockaddr_in);
3049                 sfamily = AF_INET;
3050                 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
3051                                 ntohs(sport));
3052         }
3053
3054         if (server->ssocket) {
3055                 socket = server->ssocket;
3056         } else {
3057                 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
3058                                    IPPROTO_TCP, &server->ssocket, 1);
3059                 if (rc < 0) {
3060                         cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
3061                         return rc;
3062                 }
3063
3064                 /* BB other socket options to set KEEPALIVE, NODELAY? */
3065                 cifs_dbg(FYI, "Socket created\n");
3066                 socket = server->ssocket;
3067                 socket->sk->sk_allocation = GFP_NOFS;
3068                 socket->sk->sk_use_task_frag = false;
3069                 if (sfamily == AF_INET6)
3070                         cifs_reclassify_socket6(socket);
3071                 else
3072                         cifs_reclassify_socket4(socket);
3073         }
3074
3075         rc = bind_socket(server);
3076         if (rc < 0)
3077                 return rc;
3078
3079         /*
3080          * Eventually check for other socket options to change from
3081          * the default. sock_setsockopt not used because it expects
3082          * user space buffer
3083          */
3084         socket->sk->sk_rcvtimeo = 7 * HZ;
3085         socket->sk->sk_sndtimeo = 5 * HZ;
3086
3087         /* make the bufsizes depend on wsize/rsize and max requests */
3088         if (server->noautotune) {
3089                 if (socket->sk->sk_sndbuf < (200 * 1024))
3090                         socket->sk->sk_sndbuf = 200 * 1024;
3091                 if (socket->sk->sk_rcvbuf < (140 * 1024))
3092                         socket->sk->sk_rcvbuf = 140 * 1024;
3093         }
3094
3095         if (server->tcp_nodelay)
3096                 tcp_sock_set_nodelay(socket->sk);
3097
3098         cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
3099                  socket->sk->sk_sndbuf,
3100                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
3101
3102         rc = kernel_connect(socket, saddr, slen,
3103                             server->noblockcnt ? O_NONBLOCK : 0);
3104         /*
3105          * When mounting SMB root file systems, we do not want to block in
3106          * connect. Otherwise bail out and then let cifs_reconnect() perform
3107          * reconnect failover - if possible.
3108          */
3109         if (server->noblockcnt && rc == -EINPROGRESS)
3110                 rc = 0;
3111         if (rc < 0) {
3112                 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3113                 trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
3114                 sock_release(socket);
3115                 server->ssocket = NULL;
3116                 return rc;
3117         }
3118         trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
3119         if (sport == htons(RFC1001_PORT))
3120                 rc = ip_rfc1001_connect(server);
3121
3122         return rc;
3123 }
3124
3125 static int
3126 ip_connect(struct TCP_Server_Info *server)
3127 {
3128         __be16 *sport;
3129         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3130         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3131
3132         if (server->dstaddr.ss_family == AF_INET6)
3133                 sport = &addr6->sin6_port;
3134         else
3135                 sport = &addr->sin_port;
3136
3137         if (*sport == 0) {
3138                 int rc;
3139
3140                 /* try with 445 port at first */
3141                 *sport = htons(CIFS_PORT);
3142
3143                 rc = generic_ip_connect(server);
3144                 if (rc >= 0)
3145                         return rc;
3146
3147                 /* if it failed, try with 139 port */
3148                 *sport = htons(RFC1001_PORT);
3149         }
3150
3151         return generic_ip_connect(server);
3152 }
3153
3154 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3155 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3156                           struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3157 {
3158         /*
3159          * If we are reconnecting then should we check to see if
3160          * any requested capabilities changed locally e.g. via
3161          * remount but we can not do much about it here
3162          * if they have (even if we could detect it by the following)
3163          * Perhaps we could add a backpointer to array of sb from tcon
3164          * or if we change to make all sb to same share the same
3165          * sb as NFS - then we only have one backpointer to sb.
3166          * What if we wanted to mount the server share twice once with
3167          * and once without posixacls or posix paths?
3168          */
3169         __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3170
3171         if (ctx && ctx->no_linux_ext) {
3172                 tcon->fsUnixInfo.Capability = 0;
3173                 tcon->unix_ext = 0; /* Unix Extensions disabled */
3174                 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
3175                 return;
3176         } else if (ctx)
3177                 tcon->unix_ext = 1; /* Unix Extensions supported */
3178
3179         if (!tcon->unix_ext) {
3180                 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
3181                 return;
3182         }
3183
3184         if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
3185                 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3186
3187                 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
3188                 /*
3189                  * check for reconnect case in which we do not
3190                  * want to change the mount behavior if we can avoid it
3191                  */
3192                 if (ctx == NULL) {
3193                         /*
3194                          * turn off POSIX ACL and PATHNAMES if not set
3195                          * originally at mount time
3196                          */
3197                         if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
3198                                 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3199                         if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3200                                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3201                                         cifs_dbg(VFS, "POSIXPATH support change\n");
3202                                 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3203                         } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3204                                 cifs_dbg(VFS, "possible reconnect error\n");
3205                                 cifs_dbg(VFS, "server disabled POSIX path support\n");
3206                         }
3207                 }
3208
3209                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3210                         cifs_dbg(VFS, "per-share encryption not supported yet\n");
3211
3212                 cap &= CIFS_UNIX_CAP_MASK;
3213                 if (ctx && ctx->no_psx_acl)
3214                         cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3215                 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
3216                         cifs_dbg(FYI, "negotiated posix acl support\n");
3217                         if (cifs_sb)
3218                                 cifs_sb->mnt_cifs_flags |=
3219                                         CIFS_MOUNT_POSIXACL;
3220                 }
3221
3222                 if (ctx && ctx->posix_paths == 0)
3223                         cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3224                 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
3225                         cifs_dbg(FYI, "negotiate posix pathnames\n");
3226                         if (cifs_sb)
3227                                 cifs_sb->mnt_cifs_flags |=
3228                                         CIFS_MOUNT_POSIX_PATHS;
3229                 }
3230
3231                 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
3232 #ifdef CONFIG_CIFS_DEBUG2
3233                 if (cap & CIFS_UNIX_FCNTL_CAP)
3234                         cifs_dbg(FYI, "FCNTL cap\n");
3235                 if (cap & CIFS_UNIX_EXTATTR_CAP)
3236                         cifs_dbg(FYI, "EXTATTR cap\n");
3237                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3238                         cifs_dbg(FYI, "POSIX path cap\n");
3239                 if (cap & CIFS_UNIX_XATTR_CAP)
3240                         cifs_dbg(FYI, "XATTR cap\n");
3241                 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
3242                         cifs_dbg(FYI, "POSIX ACL cap\n");
3243                 if (cap & CIFS_UNIX_LARGE_READ_CAP)
3244                         cifs_dbg(FYI, "very large read cap\n");
3245                 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
3246                         cifs_dbg(FYI, "very large write cap\n");
3247                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
3248                         cifs_dbg(FYI, "transport encryption cap\n");
3249                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3250                         cifs_dbg(FYI, "mandatory transport encryption cap\n");
3251 #endif /* CIFS_DEBUG2 */
3252                 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
3253                         if (ctx == NULL)
3254                                 cifs_dbg(FYI, "resetting capabilities failed\n");
3255                         else
3256                                 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");
3257
3258                 }
3259         }
3260 }
3261 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3262
3263 int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
3264 {
3265         struct smb3_fs_context *ctx = cifs_sb->ctx;
3266
3267         INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
3268
3269         spin_lock_init(&cifs_sb->tlink_tree_lock);
3270         cifs_sb->tlink_tree = RB_ROOT;
3271
3272         cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
3273                  ctx->file_mode, ctx->dir_mode);
3274
3275         /* this is needed for ASCII cp to Unicode converts */
3276         if (ctx->iocharset == NULL) {
3277                 /* load_nls_default cannot return null */
3278                 cifs_sb->local_nls = load_nls_default();
3279         } else {
3280                 cifs_sb->local_nls = load_nls(ctx->iocharset);
3281                 if (cifs_sb->local_nls == NULL) {
3282                         cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
3283                                  ctx->iocharset);
3284                         return -ELIBACC;
3285                 }
3286         }
3287         ctx->local_nls = cifs_sb->local_nls;
3288
3289         smb3_update_mnt_flags(cifs_sb);
3290
3291         if (ctx->direct_io)
3292                 cifs_dbg(FYI, "mounting share using direct i/o\n");
3293         if (ctx->cache_ro) {
3294                 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
3295                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
3296         } else if (ctx->cache_rw) {
3297                 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
3298                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
3299                                             CIFS_MOUNT_RW_CACHE);
3300         }
3301
3302         if ((ctx->cifs_acl) && (ctx->dynperm))
3303                 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
3304
3305         if (ctx->prepath) {
3306                 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
3307                 if (cifs_sb->prepath == NULL)
3308                         return -ENOMEM;
3309                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3310         }
3311
3312         return 0;
3313 }
3314
3315 /* Release all succeed connections */
3316 void cifs_mount_put_conns(struct cifs_mount_ctx *mnt_ctx)
3317 {
3318         int rc = 0;
3319
3320         if (mnt_ctx->tcon)
3321                 cifs_put_tcon(mnt_ctx->tcon);
3322         else if (mnt_ctx->ses)
3323                 cifs_put_smb_ses(mnt_ctx->ses);
3324         else if (mnt_ctx->server)
3325                 cifs_put_tcp_session(mnt_ctx->server, 0);
3326         mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
3327         free_xid(mnt_ctx->xid);
3328 }
3329
3330 int cifs_mount_get_session(struct cifs_mount_ctx *mnt_ctx)
3331 {
3332         struct TCP_Server_Info *server = NULL;
3333         struct smb3_fs_context *ctx;
3334         struct cifs_ses *ses = NULL;
3335         unsigned int xid;
3336         int rc = 0;
3337
3338         xid = get_xid();
3339
3340         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->fs_ctx)) {
3341                 rc = -EINVAL;
3342                 goto out;
3343         }
3344         ctx = mnt_ctx->fs_ctx;
3345
3346         /* get a reference to a tcp session */
3347         server = cifs_get_tcp_session(ctx, NULL);
3348         if (IS_ERR(server)) {
3349                 rc = PTR_ERR(server);
3350                 server = NULL;
3351                 goto out;
3352         }
3353
3354         /* get a reference to a SMB session */
3355         ses = cifs_get_smb_ses(server, ctx);
3356         if (IS_ERR(ses)) {
3357                 rc = PTR_ERR(ses);
3358                 ses = NULL;
3359                 goto out;
3360         }
3361
3362         if ((ctx->persistent == true) && (!(ses->server->capabilities &
3363                                             SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
3364                 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
3365                 rc = -EOPNOTSUPP;
3366         }
3367
3368 out:
3369         mnt_ctx->xid = xid;
3370         mnt_ctx->server = server;
3371         mnt_ctx->ses = ses;
3372         mnt_ctx->tcon = NULL;
3373
3374         return rc;
3375 }
3376
3377 int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx)
3378 {
3379         struct TCP_Server_Info *server;
3380         struct cifs_sb_info *cifs_sb;
3381         struct smb3_fs_context *ctx;
3382         struct cifs_tcon *tcon = NULL;
3383         int rc = 0;
3384
3385         if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->server || !mnt_ctx->ses || !mnt_ctx->fs_ctx ||
3386                          !mnt_ctx->cifs_sb)) {
3387                 rc = -EINVAL;
3388                 goto out;
3389         }
3390         server = mnt_ctx->server;
3391         ctx = mnt_ctx->fs_ctx;
3392         cifs_sb = mnt_ctx->cifs_sb;
3393
3394         /* search for existing tcon to this server share */
3395         tcon = cifs_get_tcon(mnt_ctx->ses, ctx);
3396         if (IS_ERR(tcon)) {
3397                 rc = PTR_ERR(tcon);
3398                 tcon = NULL;
3399                 goto out;
3400         }
3401
3402         /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
3403         if (tcon->posix_extensions)
3404                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
3405
3406 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3407         /* tell server which Unix caps we support */
3408         if (cap_unix(tcon->ses)) {
3409                 /*
3410                  * reset of caps checks mount to see if unix extensions disabled
3411                  * for just this mount.
3412                  */
3413                 reset_cifs_unix_caps(mnt_ctx->xid, tcon, cifs_sb, ctx);
3414                 spin_lock(&tcon->ses->server->srv_lock);
3415                 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
3416                     (le64_to_cpu(tcon->fsUnixInfo.Capability) &
3417                      CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
3418                         spin_unlock(&tcon->ses->server->srv_lock);
3419                         rc = -EACCES;
3420                         goto out;
3421                 }
3422                 spin_unlock(&tcon->ses->server->srv_lock);
3423         } else
3424 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3425                 tcon->unix_ext = 0; /* server does not support them */
3426
3427         /* do not care if a following call succeed - informational */
3428         if (!tcon->pipe && server->ops->qfs_tcon) {
3429                 server->ops->qfs_tcon(mnt_ctx->xid, tcon, cifs_sb);
3430                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
3431                         if (tcon->fsDevInfo.DeviceCharacteristics &
3432                             cpu_to_le32(FILE_READ_ONLY_DEVICE))
3433                                 cifs_dbg(VFS, "mounted to read only share\n");
3434                         else if ((cifs_sb->mnt_cifs_flags &
3435                                   CIFS_MOUNT_RW_CACHE) == 0)
3436                                 cifs_dbg(VFS, "read only mount of RW share\n");
3437                         /* no need to log a RW mount of a typical RW share */
3438                 }
3439         }
3440
3441         /*
3442          * Clamp the rsize/wsize mount arguments if they are too big for the server
3443          * and set the rsize/wsize to the negotiated values if not passed in by
3444          * the user on mount
3445          */
3446         if ((cifs_sb->ctx->wsize == 0) ||
3447             (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx))) {
3448                 cifs_sb->ctx->wsize =
3449                         round_down(server->ops->negotiate_wsize(tcon, ctx), PAGE_SIZE);
3450                 /*
3451                  * in the very unlikely event that the server sent a max write size under PAGE_SIZE,
3452                  * (which would get rounded down to 0) then reset wsize to absolute minimum eg 4096
3453                  */
3454                 if (cifs_sb->ctx->wsize == 0) {
3455                         cifs_sb->ctx->wsize = PAGE_SIZE;
3456                         cifs_dbg(VFS, "wsize too small, reset to minimum ie PAGE_SIZE, usually 4096\n");
3457                 }
3458         }
3459         if ((cifs_sb->ctx->rsize == 0) ||
3460             (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
3461                 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
3462
3463         /*
3464          * The cookie is initialized from volume info returned above.
3465          * Inside cifs_fscache_get_super_cookie it checks
3466          * that we do not get super cookie twice.
3467          */
3468         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
3469                 cifs_fscache_get_super_cookie(tcon);
3470
3471 out:
3472         mnt_ctx->tcon = tcon;
3473         return rc;
3474 }
3475
3476 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
3477                              struct cifs_tcon *tcon)
3478 {
3479         struct tcon_link *tlink;
3480
3481         /* hang the tcon off of the superblock */
3482         tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
3483         if (tlink == NULL)
3484                 return -ENOMEM;
3485
3486         tlink->tl_uid = ses->linux_uid;
3487         tlink->tl_tcon = tcon;
3488         tlink->tl_time = jiffies;
3489         set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
3490         set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3491
3492         cifs_sb->master_tlink = tlink;
3493         spin_lock(&cifs_sb->tlink_tree_lock);
3494         tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
3495         spin_unlock(&cifs_sb->tlink_tree_lock);
3496
3497         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
3498                                 TLINK_IDLE_EXPIRE);
3499         return 0;
3500 }
3501
3502 static int
3503 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3504                                         unsigned int xid,
3505                                         struct cifs_tcon *tcon,
3506                                         struct cifs_sb_info *cifs_sb,
3507                                         char *full_path,
3508                                         int added_treename)
3509 {
3510         int rc;
3511         char *s;
3512         char sep, tmp;
3513         int skip = added_treename ? 1 : 0;
3514
3515         sep = CIFS_DIR_SEP(cifs_sb);
3516         s = full_path;
3517
3518         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3519         while (rc == 0) {
3520                 /* skip separators */
3521                 while (*s == sep)
3522                         s++;
3523                 if (!*s)
3524                         break;
3525                 /* next separator */
3526                 while (*s && *s != sep)
3527                         s++;
3528                 /*
3529                  * if the treename is added, we then have to skip the first
3530                  * part within the separators
3531                  */
3532                 if (skip) {
3533                         skip = 0;
3534                         continue;
3535                 }
3536                 /*
3537                  * temporarily null-terminate the path at the end of
3538                  * the current component
3539                  */
3540                 tmp = *s;
3541                 *s = 0;
3542                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3543                                                      full_path);
3544                 *s = tmp;
3545         }
3546         return rc;
3547 }
3548
3549 /*
3550  * Check if path is remote (i.e. a DFS share).
3551  *
3552  * Return -EREMOTE if it is, otherwise 0 or -errno.
3553  */
3554 int cifs_is_path_remote(struct cifs_mount_ctx *mnt_ctx)
3555 {
3556         int rc;
3557         struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
3558         struct TCP_Server_Info *server = mnt_ctx->server;
3559         unsigned int xid = mnt_ctx->xid;
3560         struct cifs_tcon *tcon = mnt_ctx->tcon;
3561         struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
3562         char *full_path;
3563
3564         if (!server->ops->is_path_accessible)
3565                 return -EOPNOTSUPP;
3566
3567         /*
3568          * cifs_build_path_to_root works only when we have a valid tcon
3569          */
3570         full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3571                                             tcon->Flags & SMB_SHARE_IS_IN_DFS);
3572         if (full_path == NULL)
3573                 return -ENOMEM;
3574
3575         cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3576
3577         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3578                                              full_path);
3579         if (rc != 0 && rc != -EREMOTE)
3580                 goto out;
3581
3582         if (rc != -EREMOTE) {
3583                 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3584                         cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3585                 if (rc != 0) {
3586                         cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3587                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3588                         rc = 0;
3589                 }
3590         }
3591
3592 out:
3593         kfree(full_path);
3594         return rc;
3595 }
3596
3597 #ifdef CONFIG_CIFS_DFS_UPCALL
3598 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3599 {
3600         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3601         bool isdfs;
3602         int rc;
3603
3604         INIT_LIST_HEAD(&mnt_ctx.dfs_ses_list);
3605
3606         rc = dfs_mount_share(&mnt_ctx, &isdfs);
3607         if (rc)
3608                 goto error;
3609         if (!isdfs)
3610                 goto out;
3611
3612         /*
3613          * After reconnecting to a different server, unique ids won't match anymore, so we disable
3614          * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
3615          */
3616         cifs_autodisable_serverino(cifs_sb);
3617         /*
3618          * Force the use of prefix path to support failover on DFS paths that resolve to targets
3619          * that have different prefix paths.
3620          */
3621         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3622         kfree(cifs_sb->prepath);
3623         cifs_sb->prepath = ctx->prepath;
3624         ctx->prepath = NULL;
3625
3626 out:
3627         cifs_try_adding_channels(mnt_ctx.ses);
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         dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
3637         cifs_mount_put_conns(&mnt_ctx);
3638         return rc;
3639 }
3640 #else
3641 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3642 {
3643         int rc = 0;
3644         struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3645
3646         rc = cifs_mount_get_session(&mnt_ctx);
3647         if (rc)
3648                 goto error;
3649
3650         rc = cifs_mount_get_tcon(&mnt_ctx);
3651         if (rc)
3652                 goto error;
3653
3654         rc = cifs_is_path_remote(&mnt_ctx);
3655         if (rc == -EREMOTE)
3656                 rc = -EOPNOTSUPP;
3657         if (rc)
3658                 goto error;
3659
3660         rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3661         if (rc)
3662                 goto error;
3663
3664         free_xid(mnt_ctx.xid);
3665         return rc;
3666
3667 error:
3668         cifs_mount_put_conns(&mnt_ctx);
3669         return rc;
3670 }
3671 #endif
3672
3673 /*
3674  * Issue a TREE_CONNECT request.
3675  */
3676 int
3677 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3678          const char *tree, struct cifs_tcon *tcon,
3679          const struct nls_table *nls_codepage)
3680 {
3681         struct smb_hdr *smb_buffer;
3682         struct smb_hdr *smb_buffer_response;
3683         TCONX_REQ *pSMB;
3684         TCONX_RSP *pSMBr;
3685         unsigned char *bcc_ptr;
3686         int rc = 0;
3687         int length;
3688         __u16 bytes_left, count;
3689
3690         if (ses == NULL)
3691                 return -EIO;
3692
3693         smb_buffer = cifs_buf_get();
3694         if (smb_buffer == NULL)
3695                 return -ENOMEM;
3696
3697         smb_buffer_response = smb_buffer;
3698
3699         header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3700                         NULL /*no tid */, 4 /*wct */);
3701
3702         smb_buffer->Mid = get_next_mid(ses->server);
3703         smb_buffer->Uid = ses->Suid;
3704         pSMB = (TCONX_REQ *) smb_buffer;
3705         pSMBr = (TCONX_RSP *) smb_buffer_response;
3706
3707         pSMB->AndXCommand = 0xFF;
3708         pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3709         bcc_ptr = &pSMB->Password[0];
3710
3711         pSMB->PasswordLength = cpu_to_le16(1);  /* minimum */
3712         *bcc_ptr = 0; /* password is null byte */
3713         bcc_ptr++;              /* skip password */
3714         /* already aligned so no need to do it below */
3715
3716         if (ses->server->sign)
3717                 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3718
3719         if (ses->capabilities & CAP_STATUS32)
3720                 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3721
3722         if (ses->capabilities & CAP_DFS)
3723                 smb_buffer->Flags2 |= SMBFLG2_DFS;
3724
3725         if (ses->capabilities & CAP_UNICODE) {
3726                 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3727                 length =
3728                     cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3729                         6 /* max utf8 char length in bytes */ *
3730                         (/* server len*/ + 256 /* share len */), nls_codepage);
3731                 bcc_ptr += 2 * length;  /* convert num 16 bit words to bytes */
3732                 bcc_ptr += 2;   /* skip trailing null */
3733         } else {                /* ASCII */
3734                 strcpy(bcc_ptr, tree);
3735                 bcc_ptr += strlen(tree) + 1;
3736         }
3737         strcpy(bcc_ptr, "?????");
3738         bcc_ptr += strlen("?????");
3739         bcc_ptr += 1;
3740         count = bcc_ptr - &pSMB->Password[0];
3741         be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3742         pSMB->ByteCount = cpu_to_le16(count);
3743
3744         rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3745                          0);
3746
3747         /* above now done in SendReceive */
3748         if (rc == 0) {
3749                 bool is_unicode;
3750
3751                 tcon->tid = smb_buffer_response->Tid;
3752                 bcc_ptr = pByteArea(smb_buffer_response);
3753                 bytes_left = get_bcc(smb_buffer_response);
3754                 length = strnlen(bcc_ptr, bytes_left - 2);
3755                 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3756                         is_unicode = true;
3757                 else
3758                         is_unicode = false;
3759
3760
3761                 /* skip service field (NB: this field is always ASCII) */
3762                 if (length == 3) {
3763                         if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3764                             (bcc_ptr[2] == 'C')) {
3765                                 cifs_dbg(FYI, "IPC connection\n");
3766                                 tcon->ipc = true;
3767                                 tcon->pipe = true;
3768                         }
3769                 } else if (length == 2) {
3770                         if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3771                                 /* the most common case */
3772                                 cifs_dbg(FYI, "disk share connection\n");
3773                         }
3774                 }
3775                 bcc_ptr += length + 1;
3776                 bytes_left -= (length + 1);
3777                 strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
3778
3779                 /* mostly informational -- no need to fail on error here */
3780                 kfree(tcon->nativeFileSystem);
3781                 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3782                                                       bytes_left, is_unicode,
3783                                                       nls_codepage);
3784
3785                 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3786
3787                 if ((smb_buffer_response->WordCount == 3) ||
3788                          (smb_buffer_response->WordCount == 7))
3789                         /* field is in same location */
3790                         tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3791                 else
3792                         tcon->Flags = 0;
3793                 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3794         }
3795
3796         cifs_buf_release(smb_buffer);
3797         return rc;
3798 }
3799
3800 static void delayed_free(struct rcu_head *p)
3801 {
3802         struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3803
3804         unload_nls(cifs_sb->local_nls);
3805         smb3_cleanup_fs_context(cifs_sb->ctx);
3806         kfree(cifs_sb);
3807 }
3808
3809 void
3810 cifs_umount(struct cifs_sb_info *cifs_sb)
3811 {
3812         struct rb_root *root = &cifs_sb->tlink_tree;
3813         struct rb_node *node;
3814         struct tcon_link *tlink;
3815
3816         cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3817
3818         spin_lock(&cifs_sb->tlink_tree_lock);
3819         while ((node = rb_first(root))) {
3820                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3821                 cifs_get_tlink(tlink);
3822                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3823                 rb_erase(node, root);
3824
3825                 spin_unlock(&cifs_sb->tlink_tree_lock);
3826                 cifs_put_tlink(tlink);
3827                 spin_lock(&cifs_sb->tlink_tree_lock);
3828         }
3829         spin_unlock(&cifs_sb->tlink_tree_lock);
3830
3831         kfree(cifs_sb->prepath);
3832         call_rcu(&cifs_sb->rcu, delayed_free);
3833 }
3834
3835 int
3836 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
3837                         struct TCP_Server_Info *server)
3838 {
3839         int rc = 0;
3840
3841         if (!server->ops->need_neg || !server->ops->negotiate)
3842                 return -ENOSYS;
3843
3844         /* only send once per connect */
3845         spin_lock(&server->srv_lock);
3846         if (server->tcpStatus != CifsGood &&
3847             server->tcpStatus != CifsNew &&
3848             server->tcpStatus != CifsNeedNegotiate) {
3849                 spin_unlock(&server->srv_lock);
3850                 return -EHOSTDOWN;
3851         }
3852
3853         if (!server->ops->need_neg(server) &&
3854             server->tcpStatus == CifsGood) {
3855                 spin_unlock(&server->srv_lock);
3856                 return 0;
3857         }
3858
3859         server->tcpStatus = CifsInNegotiate;
3860         spin_unlock(&server->srv_lock);
3861
3862         rc = server->ops->negotiate(xid, ses, server);
3863         if (rc == 0) {
3864                 spin_lock(&server->srv_lock);
3865                 if (server->tcpStatus == CifsInNegotiate)
3866                         server->tcpStatus = CifsGood;
3867                 else
3868                         rc = -EHOSTDOWN;
3869                 spin_unlock(&server->srv_lock);
3870         } else {
3871                 spin_lock(&server->srv_lock);
3872                 if (server->tcpStatus == CifsInNegotiate)
3873                         server->tcpStatus = CifsNeedNegotiate;
3874                 spin_unlock(&server->srv_lock);
3875         }
3876
3877         return rc;
3878 }
3879
3880 int
3881 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3882                    struct TCP_Server_Info *server,
3883                    struct nls_table *nls_info)
3884 {
3885         int rc = -ENOSYS;
3886         struct TCP_Server_Info *pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
3887         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&pserver->dstaddr;
3888         struct sockaddr_in *addr = (struct sockaddr_in *)&pserver->dstaddr;
3889         bool is_binding = false;
3890
3891         spin_lock(&ses->ses_lock);
3892         cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
3893                  __func__, ses->chans_need_reconnect);
3894
3895         if (ses->ses_status != SES_GOOD &&
3896             ses->ses_status != SES_NEW &&
3897             ses->ses_status != SES_NEED_RECON) {
3898                 spin_unlock(&ses->ses_lock);
3899                 return -EHOSTDOWN;
3900         }
3901
3902         /* only send once per connect */
3903         spin_lock(&ses->chan_lock);
3904         if (CIFS_ALL_CHANS_GOOD(ses)) {
3905                 if (ses->ses_status == SES_NEED_RECON)
3906                         ses->ses_status = SES_GOOD;
3907                 spin_unlock(&ses->chan_lock);
3908                 spin_unlock(&ses->ses_lock);
3909                 return 0;
3910         }
3911
3912         cifs_chan_set_in_reconnect(ses, server);
3913         is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
3914         spin_unlock(&ses->chan_lock);
3915
3916         if (!is_binding) {
3917                 ses->ses_status = SES_IN_SETUP;
3918
3919                 /* force iface_list refresh */
3920                 ses->iface_last_update = 0;
3921         }
3922         spin_unlock(&ses->ses_lock);
3923
3924         /* update ses ip_addr only for primary chan */
3925         if (server == pserver) {
3926                 if (server->dstaddr.ss_family == AF_INET6)
3927                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
3928                 else
3929                         scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
3930         }
3931
3932         if (!is_binding) {
3933                 ses->capabilities = server->capabilities;
3934                 if (!linuxExtEnabled)
3935                         ses->capabilities &= (~server->vals->cap_unix);
3936
3937                 if (ses->auth_key.response) {
3938                         cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3939                                  ses->auth_key.response);
3940                         kfree_sensitive(ses->auth_key.response);
3941                         ses->auth_key.response = NULL;
3942                         ses->auth_key.len = 0;
3943                 }
3944         }
3945
3946         cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3947                  server->sec_mode, server->capabilities, server->timeAdj);
3948
3949         if (server->ops->sess_setup)
3950                 rc = server->ops->sess_setup(xid, ses, server, nls_info);
3951
3952         if (rc) {
3953                 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3954                 spin_lock(&ses->ses_lock);
3955                 if (ses->ses_status == SES_IN_SETUP)
3956                         ses->ses_status = SES_NEED_RECON;
3957                 spin_lock(&ses->chan_lock);
3958                 cifs_chan_clear_in_reconnect(ses, server);
3959                 spin_unlock(&ses->chan_lock);
3960                 spin_unlock(&ses->ses_lock);
3961         } else {
3962                 spin_lock(&ses->ses_lock);
3963                 if (ses->ses_status == SES_IN_SETUP)
3964                         ses->ses_status = SES_GOOD;
3965                 spin_lock(&ses->chan_lock);
3966                 cifs_chan_clear_in_reconnect(ses, server);
3967                 cifs_chan_clear_need_reconnect(ses, server);
3968                 spin_unlock(&ses->chan_lock);
3969                 spin_unlock(&ses->ses_lock);
3970         }
3971
3972         return rc;
3973 }
3974
3975 static int
3976 cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3977 {
3978         ctx->sectype = ses->sectype;
3979
3980         /* krb5 is special, since we don't need username or pw */
3981         if (ctx->sectype == Kerberos)
3982                 return 0;
3983
3984         return cifs_set_cifscreds(ctx, ses);
3985 }
3986
3987 static struct cifs_tcon *
3988 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3989 {
3990         int rc;
3991         struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3992         struct cifs_ses *ses;
3993         struct cifs_tcon *tcon = NULL;
3994         struct smb3_fs_context *ctx;
3995
3996         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3997         if (ctx == NULL)
3998                 return ERR_PTR(-ENOMEM);
3999
4000         ctx->local_nls = cifs_sb->local_nls;
4001         ctx->linux_uid = fsuid;
4002         ctx->cred_uid = fsuid;
4003         ctx->UNC = master_tcon->tree_name;
4004         ctx->retry = master_tcon->retry;
4005         ctx->nocase = master_tcon->nocase;
4006         ctx->nohandlecache = master_tcon->nohandlecache;
4007         ctx->local_lease = master_tcon->local_lease;
4008         ctx->no_lease = master_tcon->no_lease;
4009         ctx->resilient = master_tcon->use_resilient;
4010         ctx->persistent = master_tcon->use_persistent;
4011         ctx->handle_timeout = master_tcon->handle_timeout;
4012         ctx->no_linux_ext = !master_tcon->unix_ext;
4013         ctx->linux_ext = master_tcon->posix_extensions;
4014         ctx->sectype = master_tcon->ses->sectype;
4015         ctx->sign = master_tcon->ses->sign;
4016         ctx->seal = master_tcon->seal;
4017         ctx->witness = master_tcon->use_witness;
4018
4019         rc = cifs_set_vol_auth(ctx, master_tcon->ses);
4020         if (rc) {
4021                 tcon = ERR_PTR(rc);
4022                 goto out;
4023         }
4024
4025         /* get a reference for the same TCP session */
4026         spin_lock(&cifs_tcp_ses_lock);
4027         ++master_tcon->ses->server->srv_count;
4028         spin_unlock(&cifs_tcp_ses_lock);
4029
4030         ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
4031         if (IS_ERR(ses)) {
4032                 tcon = (struct cifs_tcon *)ses;
4033                 cifs_put_tcp_session(master_tcon->ses->server, 0);
4034                 goto out;
4035         }
4036
4037         tcon = cifs_get_tcon(ses, ctx);
4038         if (IS_ERR(tcon)) {
4039                 cifs_put_smb_ses(ses);
4040                 goto out;
4041         }
4042
4043 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
4044         if (cap_unix(ses))
4045                 reset_cifs_unix_caps(0, tcon, NULL, ctx);
4046 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
4047
4048 out:
4049         kfree(ctx->username);
4050         kfree_sensitive(ctx->password);
4051         kfree(ctx);
4052
4053         return tcon;
4054 }
4055
4056 struct cifs_tcon *
4057 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
4058 {
4059         return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
4060 }
4061
4062 /* find and return a tlink with given uid */
4063 static struct tcon_link *
4064 tlink_rb_search(struct rb_root *root, kuid_t uid)
4065 {
4066         struct rb_node *node = root->rb_node;
4067         struct tcon_link *tlink;
4068
4069         while (node) {
4070                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
4071
4072                 if (uid_gt(tlink->tl_uid, uid))
4073                         node = node->rb_left;
4074                 else if (uid_lt(tlink->tl_uid, uid))
4075                         node = node->rb_right;
4076                 else
4077                         return tlink;
4078         }
4079         return NULL;
4080 }
4081
4082 /* insert a tcon_link into the tree */
4083 static void
4084 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
4085 {
4086         struct rb_node **new = &(root->rb_node), *parent = NULL;
4087         struct tcon_link *tlink;
4088
4089         while (*new) {
4090                 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
4091                 parent = *new;
4092
4093                 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
4094                         new = &((*new)->rb_left);
4095                 else
4096                         new = &((*new)->rb_right);
4097         }
4098
4099         rb_link_node(&new_tlink->tl_rbnode, parent, new);
4100         rb_insert_color(&new_tlink->tl_rbnode, root);
4101 }
4102
4103 /*
4104  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4105  * current task.
4106  *
4107  * If the superblock doesn't refer to a multiuser mount, then just return
4108  * the master tcon for the mount.
4109  *
4110  * First, search the rbtree for an existing tcon for this fsuid. If one
4111  * exists, then check to see if it's pending construction. If it is then wait
4112  * for construction to complete. Once it's no longer pending, check to see if
4113  * it failed and either return an error or retry construction, depending on
4114  * the timeout.
4115  *
4116  * If one doesn't exist then insert a new tcon_link struct into the tree and
4117  * try to construct a new one.
4118  */
4119 struct tcon_link *
4120 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4121 {
4122         int ret;
4123         kuid_t fsuid = current_fsuid();
4124         struct tcon_link *tlink, *newtlink;
4125
4126         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4127                 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4128
4129         spin_lock(&cifs_sb->tlink_tree_lock);
4130         tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4131         if (tlink)
4132                 cifs_get_tlink(tlink);
4133         spin_unlock(&cifs_sb->tlink_tree_lock);
4134
4135         if (tlink == NULL) {
4136                 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4137                 if (newtlink == NULL)
4138                         return ERR_PTR(-ENOMEM);
4139                 newtlink->tl_uid = fsuid;
4140                 newtlink->tl_tcon = ERR_PTR(-EACCES);
4141                 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4142                 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4143                 cifs_get_tlink(newtlink);
4144
4145                 spin_lock(&cifs_sb->tlink_tree_lock);
4146                 /* was one inserted after previous search? */
4147                 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4148                 if (tlink) {
4149                         cifs_get_tlink(tlink);
4150                         spin_unlock(&cifs_sb->tlink_tree_lock);
4151                         kfree(newtlink);
4152                         goto wait_for_construction;
4153                 }
4154                 tlink = newtlink;
4155                 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4156                 spin_unlock(&cifs_sb->tlink_tree_lock);
4157         } else {
4158 wait_for_construction:
4159                 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4160                                   TASK_INTERRUPTIBLE);
4161                 if (ret) {
4162                         cifs_put_tlink(tlink);
4163                         return ERR_PTR(-ERESTARTSYS);
4164                 }
4165
4166                 /* if it's good, return it */
4167                 if (!IS_ERR(tlink->tl_tcon))
4168                         return tlink;
4169
4170                 /* return error if we tried this already recently */
4171                 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4172                         cifs_put_tlink(tlink);
4173                         return ERR_PTR(-EACCES);
4174                 }
4175
4176                 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4177                         goto wait_for_construction;
4178         }
4179
4180         tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4181         clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4182         wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4183
4184         if (IS_ERR(tlink->tl_tcon)) {
4185                 cifs_put_tlink(tlink);
4186                 return ERR_PTR(-EACCES);
4187         }
4188
4189         return tlink;
4190 }
4191
4192 /*
4193  * periodic workqueue job that scans tcon_tree for a superblock and closes
4194  * out tcons.
4195  */
4196 static void
4197 cifs_prune_tlinks(struct work_struct *work)
4198 {
4199         struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4200                                                     prune_tlinks.work);
4201         struct rb_root *root = &cifs_sb->tlink_tree;
4202         struct rb_node *node;
4203         struct rb_node *tmp;
4204         struct tcon_link *tlink;
4205
4206         /*
4207          * Because we drop the spinlock in the loop in order to put the tlink
4208          * it's not guarded against removal of links from the tree. The only
4209          * places that remove entries from the tree are this function and
4210          * umounts. Because this function is non-reentrant and is canceled
4211          * before umount can proceed, this is safe.
4212          */
4213         spin_lock(&cifs_sb->tlink_tree_lock);
4214         node = rb_first(root);
4215         while (node != NULL) {
4216                 tmp = node;
4217                 node = rb_next(tmp);
4218                 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4219
4220                 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4221                     atomic_read(&tlink->tl_count) != 0 ||
4222                     time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4223                         continue;
4224
4225                 cifs_get_tlink(tlink);
4226                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4227                 rb_erase(tmp, root);
4228
4229                 spin_unlock(&cifs_sb->tlink_tree_lock);
4230                 cifs_put_tlink(tlink);
4231                 spin_lock(&cifs_sb->tlink_tree_lock);
4232         }
4233         spin_unlock(&cifs_sb->tlink_tree_lock);
4234
4235         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4236                                 TLINK_IDLE_EXPIRE);
4237 }
4238
4239 #ifndef CONFIG_CIFS_DFS_UPCALL
4240 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4241 {
4242         int rc;
4243         const struct smb_version_operations *ops = tcon->ses->server->ops;
4244
4245         /* only send once per connect */
4246         spin_lock(&tcon->tc_lock);
4247
4248         /* if tcon is marked for needing reconnect, update state */
4249         if (tcon->need_reconnect)
4250                 tcon->status = TID_NEED_TCON;
4251
4252         if (tcon->status == TID_GOOD) {
4253                 spin_unlock(&tcon->tc_lock);
4254                 return 0;
4255         }
4256
4257         if (tcon->status != TID_NEW &&
4258             tcon->status != TID_NEED_TCON) {
4259                 spin_unlock(&tcon->tc_lock);
4260                 return -EHOSTDOWN;
4261         }
4262
4263         tcon->status = TID_IN_TCON;
4264         spin_unlock(&tcon->tc_lock);
4265
4266         rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
4267         if (rc) {
4268                 spin_lock(&tcon->tc_lock);
4269                 if (tcon->status == TID_IN_TCON)
4270                         tcon->status = TID_NEED_TCON;
4271                 spin_unlock(&tcon->tc_lock);
4272         } else {
4273                 spin_lock(&tcon->tc_lock);
4274                 if (tcon->status == TID_IN_TCON)
4275                         tcon->status = TID_GOOD;
4276                 tcon->need_reconnect = false;
4277                 spin_unlock(&tcon->tc_lock);
4278         }
4279
4280         return rc;
4281 }
4282 #endif