fs/cifs/connect.c

   1 /*
   2  *   fs/cifs/connect.c
   3  *
   4  *   Copyright (C) International Business Machines  Corp., 2002,2011
   5  *   Author(s): Steve French ([email protected])
   6  *
   7  *   This library is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU Lesser General Public License as published
   9  *   by the Free Software Foundation; either version 2.1 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This library is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  15  *   the GNU Lesser General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU Lesser General Public License
  18  *   along with this library; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21 #include <linux/fs.h>
  22 #include <linux/net.h>
  23 #include <linux/string.h>
  24 #include <linux/sched/mm.h>
  25 #include <linux/sched/signal.h>
  26 #include <linux/list.h>
  27 #include <linux/wait.h>
  28 #include <linux/slab.h>
  29 #include <linux/pagemap.h>
  30 #include <linux/ctype.h>
  31 #include <linux/utsname.h>
  32 #include <linux/mempool.h>
  33 #include <linux/delay.h>
  34 #include <linux/completion.h>
  35 #include <linux/kthread.h>
  36 #include <linux/pagevec.h>
  37 #include <linux/freezer.h>
  38 #include <linux/namei.h>
  39 #include <linux/uuid.h>
  40 #include <linux/uaccess.h>
  41 #include <asm/processor.h>
  42 #include <linux/inet.h>
  43 #include <linux/module.h>
  44 #include <keys/user-type.h>
  45 #include <net/ipv6.h>
  46 #include <linux/parser.h>
  47 #include <linux/bvec.h>
  48 #include "cifspdu.h"
  49 #include "cifsglob.h"
  50 #include "cifsproto.h"
  51 #include "cifs_unicode.h"
  52 #include "cifs_debug.h"
  53 #include "cifs_fs_sb.h"
  54 #include "ntlmssp.h"
  55 #include "nterr.h"
  56 #include "rfc1002pdu.h"
  57 #include "fscache.h"
  58 #include "smb2proto.h"
  59 #include "smbdirect.h"
  60 #include "dns_resolve.h"
  61 #ifdef CONFIG_CIFS_DFS_UPCALL
  62 #include "dfs_cache.h"
  63 #endif
  64
  65 extern mempool_t *cifs_req_poolp;
  66 extern bool disable_legacy_dialects;
  67
  68 /* FIXME: should these be tunable? */
  69 #define TLINK_ERROR_EXPIRE      (1 * HZ)
  70 #define TLINK_IDLE_EXPIRE       (600 * HZ)
  71
  72 enum {
  73         /* Mount options that take no arguments */
  74         Opt_user_xattr, Opt_nouser_xattr,
  75         Opt_forceuid, Opt_noforceuid,
  76         Opt_forcegid, Opt_noforcegid,
  77         Opt_noblocksend, Opt_noautotune, Opt_nolease,
  78         Opt_hard, Opt_soft, Opt_perm, Opt_noperm, Opt_nodelete,
  79         Opt_mapposix, Opt_nomapposix,
  80         Opt_mapchars, Opt_nomapchars, Opt_sfu,
  81         Opt_nosfu, Opt_nodfs, Opt_posixpaths,
  82         Opt_noposixpaths, Opt_nounix, Opt_unix,
  83         Opt_nocase,
  84         Opt_brl, Opt_nobrl,
  85         Opt_handlecache, Opt_nohandlecache,
  86         Opt_forcemandatorylock, Opt_setuidfromacl, Opt_setuids,
  87         Opt_nosetuids, Opt_dynperm, Opt_nodynperm,
  88         Opt_nohard, Opt_nosoft,
  89         Opt_nointr, Opt_intr,
  90         Opt_nostrictsync, Opt_strictsync,
  91         Opt_serverino, Opt_noserverino,
  92         Opt_rwpidforward, Opt_cifsacl, Opt_nocifsacl,
  93         Opt_acl, Opt_noacl, Opt_locallease,
  94         Opt_sign, Opt_ignore_signature, Opt_seal, Opt_noac,
  95         Opt_fsc, Opt_mfsymlinks,
  96         Opt_multiuser, Opt_sloppy, Opt_nosharesock,
  97         Opt_persistent, Opt_nopersistent,
  98         Opt_resilient, Opt_noresilient,
  99         Opt_domainauto, Opt_rdma, Opt_modesid, Opt_rootfs,
 100         Opt_multichannel, Opt_nomultichannel,
 101         Opt_compress,
 102
 103         /* Mount options which take numeric value */
 104         Opt_backupuid, Opt_backupgid, Opt_uid,
 105         Opt_cruid, Opt_gid, Opt_file_mode,
 106         Opt_dirmode, Opt_port,
 107         Opt_min_enc_offload,
 108         Opt_blocksize, Opt_rsize, Opt_wsize, Opt_actimeo,
 109         Opt_echo_interval, Opt_max_credits, Opt_handletimeout,
 110         Opt_snapshot, Opt_max_channels,
 111
 112         /* Mount options which take string value */
 113         Opt_user, Opt_pass, Opt_ip,
 114         Opt_domain, Opt_srcaddr, Opt_iocharset,
 115         Opt_netbiosname, Opt_servern,
 116         Opt_ver, Opt_vers, Opt_sec, Opt_cache,
 117
 118         /* Mount options to be ignored */
 119         Opt_ignore,
 120
 121         /* Options which could be blank */
 122         Opt_blank_pass,
 123         Opt_blank_user,
 124         Opt_blank_ip,
 125
 126         Opt_err
 127 };
 128
 129 static const match_table_t cifs_mount_option_tokens = {
 130
 131         { Opt_user_xattr, "user_xattr" },
 132         { Opt_nouser_xattr, "nouser_xattr" },
 133         { Opt_forceuid, "forceuid" },
 134         { Opt_noforceuid, "noforceuid" },
 135         { Opt_forcegid, "forcegid" },
 136         { Opt_noforcegid, "noforcegid" },
 137         { Opt_noblocksend, "noblocksend" },
 138         { Opt_noautotune, "noautotune" },
 139         { Opt_nolease, "nolease" },
 140         { Opt_hard, "hard" },
 141         { Opt_soft, "soft" },
 142         { Opt_perm, "perm" },
 143         { Opt_noperm, "noperm" },
 144         { Opt_nodelete, "nodelete" },
 145         { Opt_mapchars, "mapchars" }, /* SFU style */
 146         { Opt_nomapchars, "nomapchars" },
 147         { Opt_mapposix, "mapposix" }, /* SFM style */
 148         { Opt_nomapposix, "nomapposix" },
 149         { Opt_sfu, "sfu" },
 150         { Opt_nosfu, "nosfu" },
 151         { Opt_nodfs, "nodfs" },
 152         { Opt_posixpaths, "posixpaths" },
 153         { Opt_noposixpaths, "noposixpaths" },
 154         { Opt_nounix, "nounix" },
 155         { Opt_nounix, "nolinux" },
 156         { Opt_nounix, "noposix" },
 157         { Opt_unix, "unix" },
 158         { Opt_unix, "linux" },
 159         { Opt_unix, "posix" },
 160         { Opt_nocase, "nocase" },
 161         { Opt_nocase, "ignorecase" },
 162         { Opt_brl, "brl" },
 163         { Opt_nobrl, "nobrl" },
 164         { Opt_handlecache, "handlecache" },
 165         { Opt_nohandlecache, "nohandlecache" },
 166         { Opt_nobrl, "nolock" },
 167         { Opt_forcemandatorylock, "forcemandatorylock" },
 168         { Opt_forcemandatorylock, "forcemand" },
 169         { Opt_setuids, "setuids" },
 170         { Opt_nosetuids, "nosetuids" },
 171         { Opt_setuidfromacl, "idsfromsid" },
 172         { Opt_dynperm, "dynperm" },
 173         { Opt_nodynperm, "nodynperm" },
 174         { Opt_nohard, "nohard" },
 175         { Opt_nosoft, "nosoft" },
 176         { Opt_nointr, "nointr" },
 177         { Opt_intr, "intr" },
 178         { Opt_nostrictsync, "nostrictsync" },
 179         { Opt_strictsync, "strictsync" },
 180         { Opt_serverino, "serverino" },
 181         { Opt_noserverino, "noserverino" },
 182         { Opt_rwpidforward, "rwpidforward" },
 183         { Opt_modesid, "modefromsid" },
 184         { Opt_cifsacl, "cifsacl" },
 185         { Opt_nocifsacl, "nocifsacl" },
 186         { Opt_acl, "acl" },
 187         { Opt_noacl, "noacl" },
 188         { Opt_locallease, "locallease" },
 189         { Opt_sign, "sign" },
 190         { Opt_ignore_signature, "signloosely" },
 191         { Opt_seal, "seal" },
 192         { Opt_noac, "noac" },
 193         { Opt_fsc, "fsc" },
 194         { Opt_mfsymlinks, "mfsymlinks" },
 195         { Opt_multiuser, "multiuser" },
 196         { Opt_sloppy, "sloppy" },
 197         { Opt_nosharesock, "nosharesock" },
 198         { Opt_persistent, "persistenthandles"},
 199         { Opt_nopersistent, "nopersistenthandles"},
 200         { Opt_resilient, "resilienthandles"},
 201         { Opt_noresilient, "noresilienthandles"},
 202         { Opt_domainauto, "domainauto"},
 203         { Opt_rdma, "rdma"},
 204         { Opt_multichannel, "multichannel" },
 205         { Opt_nomultichannel, "nomultichannel" },
 206
 207         { Opt_backupuid, "backupuid=%s" },
 208         { Opt_backupgid, "backupgid=%s" },
 209         { Opt_uid, "uid=%s" },
 210         { Opt_cruid, "cruid=%s" },
 211         { Opt_gid, "gid=%s" },
 212         { Opt_file_mode, "file_mode=%s" },
 213         { Opt_dirmode, "dirmode=%s" },
 214         { Opt_dirmode, "dir_mode=%s" },
 215         { Opt_port, "port=%s" },
 216         { Opt_min_enc_offload, "esize=%s" },
 217         { Opt_blocksize, "bsize=%s" },
 218         { Opt_rsize, "rsize=%s" },
 219         { Opt_wsize, "wsize=%s" },
 220         { Opt_actimeo, "actimeo=%s" },
 221         { Opt_handletimeout, "handletimeout=%s" },
 222         { Opt_echo_interval, "echo_interval=%s" },
 223         { Opt_max_credits, "max_credits=%s" },
 224         { Opt_snapshot, "snapshot=%s" },
 225         { Opt_max_channels, "max_channels=%s" },
 226         { Opt_compress, "compress=%s" },
 227
 228         { Opt_blank_user, "user=" },
 229         { Opt_blank_user, "username=" },
 230         { Opt_user, "user=%s" },
 231         { Opt_user, "username=%s" },
 232         { Opt_blank_pass, "pass=" },
 233         { Opt_blank_pass, "password=" },
 234         { Opt_pass, "pass=%s" },
 235         { Opt_pass, "password=%s" },
 236         { Opt_blank_ip, "ip=" },
 237         { Opt_blank_ip, "addr=" },
 238         { Opt_ip, "ip=%s" },
 239         { Opt_ip, "addr=%s" },
 240         { Opt_ignore, "unc=%s" },
 241         { Opt_ignore, "target=%s" },
 242         { Opt_ignore, "path=%s" },
 243         { Opt_domain, "dom=%s" },
 244         { Opt_domain, "domain=%s" },
 245         { Opt_domain, "workgroup=%s" },
 246         { Opt_srcaddr, "srcaddr=%s" },
 247         { Opt_ignore, "prefixpath=%s" },
 248         { Opt_iocharset, "iocharset=%s" },
 249         { Opt_netbiosname, "netbiosname=%s" },
 250         { Opt_servern, "servern=%s" },
 251         { Opt_ver, "ver=%s" },
 252         { Opt_vers, "vers=%s" },
 253         { Opt_sec, "sec=%s" },
 254         { Opt_cache, "cache=%s" },
 255
 256         { Opt_ignore, "cred" },
 257         { Opt_ignore, "credentials" },
 258         { Opt_ignore, "cred=%s" },
 259         { Opt_ignore, "credentials=%s" },
 260         { Opt_ignore, "guest" },
 261         { Opt_ignore, "rw" },
 262         { Opt_ignore, "ro" },
 263         { Opt_ignore, "suid" },
 264         { Opt_ignore, "nosuid" },
 265         { Opt_ignore, "exec" },
 266         { Opt_ignore, "noexec" },
 267         { Opt_ignore, "nodev" },
 268         { Opt_ignore, "noauto" },
 269         { Opt_ignore, "dev" },
 270         { Opt_ignore, "mand" },
 271         { Opt_ignore, "nomand" },
 272         { Opt_ignore, "relatime" },
 273         { Opt_ignore, "_netdev" },
 274         { Opt_rootfs, "rootfs" },
 275
 276         { Opt_err, NULL }
 277 };
 278
 279 enum {
 280         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 281         Opt_sec_ntlmsspi, Opt_sec_ntlmssp,
 282         Opt_ntlm, Opt_sec_ntlmi, Opt_sec_ntlmv2,
 283         Opt_sec_ntlmv2i, Opt_sec_lanman,
 284         Opt_sec_none,
 285
 286         Opt_sec_err
 287 };
 288
 289 static const match_table_t cifs_secflavor_tokens = {
 290         { Opt_sec_krb5, "krb5" },
 291         { Opt_sec_krb5i, "krb5i" },
 292         { Opt_sec_krb5p, "krb5p" },
 293         { Opt_sec_ntlmsspi, "ntlmsspi" },
 294         { Opt_sec_ntlmssp, "ntlmssp" },
 295         { Opt_ntlm, "ntlm" },
 296         { Opt_sec_ntlmi, "ntlmi" },
 297         { Opt_sec_ntlmv2, "nontlm" },
 298         { Opt_sec_ntlmv2, "ntlmv2" },
 299         { Opt_sec_ntlmv2i, "ntlmv2i" },
 300         { Opt_sec_lanman, "lanman" },
 301         { Opt_sec_none, "none" },
 302
 303         { Opt_sec_err, NULL }
 304 };
 305
 306 /* cache flavors */
 307 enum {
 308         Opt_cache_loose,
 309         Opt_cache_strict,
 310         Opt_cache_none,
 311         Opt_cache_ro,
 312         Opt_cache_rw,
 313         Opt_cache_err
 314 };
 315
 316 static const match_table_t cifs_cacheflavor_tokens = {
 317         { Opt_cache_loose, "loose" },
 318         { Opt_cache_strict, "strict" },
 319         { Opt_cache_none, "none" },
 320         { Opt_cache_ro, "ro" },
 321         { Opt_cache_rw, "singleclient" },
 322         { Opt_cache_err, NULL }
 323 };
 324
 325 static const match_table_t cifs_smb_version_tokens = {
 326         { Smb_1, SMB1_VERSION_STRING },
 327         { Smb_20, SMB20_VERSION_STRING},
 328         { Smb_21, SMB21_VERSION_STRING },
 329         { Smb_30, SMB30_VERSION_STRING },
 330         { Smb_302, SMB302_VERSION_STRING },
 331         { Smb_302, ALT_SMB302_VERSION_STRING },
 332         { Smb_311, SMB311_VERSION_STRING },
 333         { Smb_311, ALT_SMB311_VERSION_STRING },
 334         { Smb_3any, SMB3ANY_VERSION_STRING },
 335         { Smb_default, SMBDEFAULT_VERSION_STRING },
 336         { Smb_version_err, NULL }
 337 };
 338
 339 static int ip_connect(struct TCP_Server_Info *server);
 340 static int generic_ip_connect(struct TCP_Server_Info *server);
 341 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
 342 static void cifs_prune_tlinks(struct work_struct *work);
 343 static char *extract_hostname(const char *unc);
 344
 345 /*
 346  * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
 347  * get their ip addresses changed at some point.
 348  *
 349  * This should be called with server->srv_mutex held.
 350  */
 351 #ifdef CONFIG_CIFS_DFS_UPCALL
 352 static int reconn_set_ipaddr(struct TCP_Server_Info *server)
 353 {
 354         int rc;
 355         int len;
 356         char *unc, *ipaddr = NULL;
 357
 358         if (!server->hostname)
 359                 return -EINVAL;
 360
 361         len = strlen(server->hostname) + 3;
 362
 363         unc = kmalloc(len, GFP_KERNEL);
 364         if (!unc) {
 365                 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
 366                 return -ENOMEM;
 367         }
 368         scnprintf(unc, len, "\\\\%s", server->hostname);
 369
 370         rc = dns_resolve_server_name_to_ip(unc, &ipaddr);
 371         kfree(unc);
 372
 373         if (rc < 0) {
 374                 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
 375                          __func__, server->hostname, rc);
 376                 return rc;
 377         }
 378
 379         spin_lock(&cifs_tcp_ses_lock);
 380         rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
 381                                   strlen(ipaddr));
 382         spin_unlock(&cifs_tcp_ses_lock);
 383         kfree(ipaddr);
 384
 385         return !rc ? -1 : 0;
 386 }
 387 #else
 388 static inline int reconn_set_ipaddr(struct TCP_Server_Info *server)
 389 {
 390         return 0;
 391 }
 392 #endif
 393
 394 #ifdef CONFIG_CIFS_DFS_UPCALL
 395 /* These functions must be called with server->srv_mutex held */
 396 static void reconn_set_next_dfs_target(struct TCP_Server_Info *server,
 397                                        struct cifs_sb_info *cifs_sb,
 398                                        struct dfs_cache_tgt_list *tgt_list,
 399                                        struct dfs_cache_tgt_iterator **tgt_it)
 400 {
 401         const char *name;
 402
 403         if (!cifs_sb || !cifs_sb->origin_fullpath)
 404                 return;
 405
 406         if (!*tgt_it) {
 407                 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
 408         } else {
 409                 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
 410                 if (!*tgt_it)
 411                         *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
 412         }
 413
 414         cifs_dbg(FYI, "%s: UNC: %s\n", __func__, cifs_sb->origin_fullpath);
 415
 416         name = dfs_cache_get_tgt_name(*tgt_it);
 417
 418         kfree(server->hostname);
 419
 420         server->hostname = extract_hostname(name);
 421         if (IS_ERR(server->hostname)) {
 422                 cifs_dbg(FYI,
 423                          "%s: failed to extract hostname from target: %ld\n",
 424                          __func__, PTR_ERR(server->hostname));
 425         }
 426 }
 427
 428 static inline int reconn_setup_dfs_targets(struct cifs_sb_info *cifs_sb,
 429                                            struct dfs_cache_tgt_list *tl)
 430 {
 431         if (!cifs_sb->origin_fullpath)
 432                 return -EOPNOTSUPP;
 433         return dfs_cache_noreq_find(cifs_sb->origin_fullpath + 1, NULL, tl);
 434 }
 435 #endif
 436
 437 /*
 438  * cifs tcp session reconnection
 439  *
 440  * mark tcp session as reconnecting so temporarily locked
 441  * mark all smb sessions as reconnecting for tcp session
 442  * reconnect tcp session
 443  * wake up waiters on reconnection? - (not needed currently)
 444  */
 445 int
 446 cifs_reconnect(struct TCP_Server_Info *server)
 447 {
 448         int rc = 0;
 449         struct list_head *tmp, *tmp2;
 450         struct cifs_ses *ses;
 451         struct cifs_tcon *tcon;
 452         struct mid_q_entry *mid_entry;
 453         struct list_head retry_list;
 454 #ifdef CONFIG_CIFS_DFS_UPCALL
 455         struct super_block *sb = NULL;
 456         struct cifs_sb_info *cifs_sb = NULL;
 457         struct dfs_cache_tgt_list tgt_list = {0};
 458         struct dfs_cache_tgt_iterator *tgt_it = NULL;
 459 #endif
 460
 461         spin_lock(&GlobalMid_Lock);
 462         server->nr_targets = 1;
 463 #ifdef CONFIG_CIFS_DFS_UPCALL
 464         spin_unlock(&GlobalMid_Lock);
 465         sb = cifs_get_tcp_super(server);
 466         if (IS_ERR(sb)) {
 467                 rc = PTR_ERR(sb);
 468                 cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n",
 469                          __func__, rc);
 470                 sb = NULL;
 471         } else {
 472                 cifs_sb = CIFS_SB(sb);
 473                 rc = reconn_setup_dfs_targets(cifs_sb, &tgt_list);
 474                 if (rc) {
 475                         cifs_sb = NULL;
 476                         if (rc != -EOPNOTSUPP) {
 477                                 cifs_server_dbg(VFS, "%s: no target servers for DFS failover\n",
 478                                                 __func__);
 479                         }
 480                 } else {
 481                         server->nr_targets = dfs_cache_get_nr_tgts(&tgt_list);
 482                 }
 483         }
 484         cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__,
 485                  server->nr_targets);
 486         spin_lock(&GlobalMid_Lock);
 487 #endif
 488         if (server->tcpStatus == CifsExiting) {
 489                 /* the demux thread will exit normally
 490                 next time through the loop */
 491                 spin_unlock(&GlobalMid_Lock);
 492 #ifdef CONFIG_CIFS_DFS_UPCALL
 493                 dfs_cache_free_tgts(&tgt_list);
 494                 cifs_put_tcp_super(sb);
 495 #endif
 496                 wake_up(&server->response_q);
 497                 return rc;
 498         } else
 499                 server->tcpStatus = CifsNeedReconnect;
 500         spin_unlock(&GlobalMid_Lock);
 501         server->maxBuf = 0;
 502         server->max_read = 0;
 503
 504         cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
 505         trace_smb3_reconnect(server->CurrentMid, server->hostname);
 506
 507         /* before reconnecting the tcp session, mark the smb session (uid)
 508                 and the tid bad so they are not used until reconnected */
 509         cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n",
 510                  __func__);
 511         spin_lock(&cifs_tcp_ses_lock);
 512         list_for_each(tmp, &server->smb_ses_list) {
 513                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 514                 ses->need_reconnect = true;
 515                 list_for_each(tmp2, &ses->tcon_list) {
 516                         tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
 517                         tcon->need_reconnect = true;
 518                 }
 519                 if (ses->tcon_ipc)
 520                         ses->tcon_ipc->need_reconnect = true;
 521         }
 522         spin_unlock(&cifs_tcp_ses_lock);
 523
 524         /* do not want to be sending data on a socket we are freeing */
 525         cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
 526         mutex_lock(&server->srv_mutex);
 527         if (server->ssocket) {
 528                 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n",
 529                          server->ssocket->state, server->ssocket->flags);
 530                 kernel_sock_shutdown(server->ssocket, SHUT_WR);
 531                 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n",
 532                          server->ssocket->state, server->ssocket->flags);
 533                 sock_release(server->ssocket);
 534                 server->ssocket = NULL;
 535         }
 536         server->sequence_number = 0;
 537         server->session_estab = false;
 538         kfree(server->session_key.response);
 539         server->session_key.response = NULL;
 540         server->session_key.len = 0;
 541         server->lstrp = jiffies;
 542
 543         /* mark submitted MIDs for retry and issue callback */
 544         INIT_LIST_HEAD(&retry_list);
 545         cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
 546         spin_lock(&GlobalMid_Lock);
 547         list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 548                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 549                 kref_get(&mid_entry->refcount);
 550                 if (mid_entry->mid_state == MID_REQUEST_SUBMITTED)
 551                         mid_entry->mid_state = MID_RETRY_NEEDED;
 552                 list_move(&mid_entry->qhead, &retry_list);
 553                 mid_entry->mid_flags |= MID_DELETED;
 554         }
 555         spin_unlock(&GlobalMid_Lock);
 556         mutex_unlock(&server->srv_mutex);
 557
 558         cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
 559         list_for_each_safe(tmp, tmp2, &retry_list) {
 560                 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 561                 list_del_init(&mid_entry->qhead);
 562                 mid_entry->callback(mid_entry);
 563                 cifs_mid_q_entry_release(mid_entry);
 564         }
 565
 566         if (cifs_rdma_enabled(server)) {
 567                 mutex_lock(&server->srv_mutex);
 568                 smbd_destroy(server);
 569                 mutex_unlock(&server->srv_mutex);
 570         }
 571
 572         do {
 573                 try_to_freeze();
 574
 575                 mutex_lock(&server->srv_mutex);
 576 #ifdef CONFIG_CIFS_DFS_UPCALL
 577                 /*
 578                  * Set up next DFS target server (if any) for reconnect. If DFS
 579                  * feature is disabled, then we will retry last server we
 580                  * connected to before.
 581                  */
 582                 reconn_set_next_dfs_target(server, cifs_sb, &tgt_list, &tgt_it);
 583 #endif
 584                 rc = reconn_set_ipaddr(server);
 585                 if (rc) {
 586                         cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
 587                                  __func__, rc);
 588                 }
 589
 590                 if (cifs_rdma_enabled(server))
 591                         rc = smbd_reconnect(server);
 592                 else
 593                         rc = generic_ip_connect(server);
 594                 if (rc) {
 595                         cifs_dbg(FYI, "reconnect error %d\n", rc);
 596                         mutex_unlock(&server->srv_mutex);
 597                         msleep(3000);
 598                 } else {
 599                         atomic_inc(&tcpSesReconnectCount);
 600                         set_credits(server, 1);
 601                         spin_lock(&GlobalMid_Lock);
 602                         if (server->tcpStatus != CifsExiting)
 603                                 server->tcpStatus = CifsNeedNegotiate;
 604                         spin_unlock(&GlobalMid_Lock);
 605                         mutex_unlock(&server->srv_mutex);
 606                 }
 607         } while (server->tcpStatus == CifsNeedReconnect);
 608
 609 #ifdef CONFIG_CIFS_DFS_UPCALL
 610         if (tgt_it) {
 611                 rc = dfs_cache_noreq_update_tgthint(cifs_sb->origin_fullpath + 1,
 612                                                     tgt_it);
 613                 if (rc) {
 614                         cifs_server_dbg(VFS, "%s: failed to update DFS target hint: rc = %d\n",
 615                                  __func__, rc);
 616                 }
 617                 rc = dfs_cache_update_vol(cifs_sb->origin_fullpath, server);
 618                 if (rc) {
 619                         cifs_server_dbg(VFS, "%s: failed to update vol info in DFS cache: rc = %d\n",
 620                                  __func__, rc);
 621                 }
 622                 dfs_cache_free_tgts(&tgt_list);
 623
 624         }
 625
 626         cifs_put_tcp_super(sb);
 627 #endif
 628         if (server->tcpStatus == CifsNeedNegotiate)
 629                 mod_delayed_work(cifsiod_wq, &server->echo, 0);
 630
 631         wake_up(&server->response_q);
 632         return rc;
 633 }
 634
 635 static void
 636 cifs_echo_request(struct work_struct *work)
 637 {
 638         int rc;
 639         struct TCP_Server_Info *server = container_of(work,
 640                                         struct TCP_Server_Info, echo.work);
 641         unsigned long echo_interval;
 642
 643         /*
 644          * If we need to renegotiate, set echo interval to zero to
 645          * immediately call echo service where we can renegotiate.
 646          */
 647         if (server->tcpStatus == CifsNeedNegotiate)
 648                 echo_interval = 0;
 649         else
 650                 echo_interval = server->echo_interval;
 651
 652         /*
 653          * We cannot send an echo if it is disabled.
 654          * Also, no need to ping if we got a response recently.
 655          */
 656
 657         if (server->tcpStatus == CifsNeedReconnect ||
 658             server->tcpStatus == CifsExiting ||
 659             server->tcpStatus == CifsNew ||
 660             (server->ops->can_echo && !server->ops->can_echo(server)) ||
 661             time_before(jiffies, server->lstrp + echo_interval - HZ))
 662                 goto requeue_echo;
 663
 664         rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
 665         if (rc)
 666                 cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
 667                          server->hostname);
 668
 669 requeue_echo:
 670         queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
 671 }
 672
 673 static bool
 674 allocate_buffers(struct TCP_Server_Info *server)
 675 {
 676         if (!server->bigbuf) {
 677                 server->bigbuf = (char *)cifs_buf_get();
 678                 if (!server->bigbuf) {
 679                         cifs_server_dbg(VFS, "No memory for large SMB response\n");
 680                         msleep(3000);
 681                         /* retry will check if exiting */
 682                         return false;
 683                 }
 684         } else if (server->large_buf) {
 685                 /* we are reusing a dirty large buf, clear its start */
 686                 memset(server->bigbuf, 0, HEADER_SIZE(server));
 687         }
 688
 689         if (!server->smallbuf) {
 690                 server->smallbuf = (char *)cifs_small_buf_get();
 691                 if (!server->smallbuf) {
 692                         cifs_server_dbg(VFS, "No memory for SMB response\n");
 693                         msleep(1000);
 694                         /* retry will check if exiting */
 695                         return false;
 696                 }
 697                 /* beginning of smb buffer is cleared in our buf_get */
 698         } else {
 699                 /* if existing small buf clear beginning */
 700                 memset(server->smallbuf, 0, HEADER_SIZE(server));
 701         }
 702
 703         return true;
 704 }
 705
 706 static bool
 707 server_unresponsive(struct TCP_Server_Info *server)
 708 {
 709         /*
 710          * We need to wait 3 echo intervals to make sure we handle such
 711          * situations right:
 712          * 1s  client sends a normal SMB request
 713          * 2s  client gets a response
 714          * 30s echo workqueue job pops, and decides we got a response recently
 715          *     and don't need to send another
 716          * ...
 717          * 65s kernel_recvmsg times out, and we see that we haven't gotten
 718          *     a response in >60s.
 719          */
 720         if ((server->tcpStatus == CifsGood ||
 721             server->tcpStatus == CifsNeedNegotiate) &&
 722             time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
 723                 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
 724                          (3 * server->echo_interval) / HZ);
 725                 cifs_reconnect(server);
 726                 return true;
 727         }
 728
 729         return false;
 730 }
 731
 732 static inline bool
 733 zero_credits(struct TCP_Server_Info *server)
 734 {
 735         int val;
 736
 737         spin_lock(&server->req_lock);
 738         val = server->credits + server->echo_credits + server->oplock_credits;
 739         if (server->in_flight == 0 && val == 0) {
 740                 spin_unlock(&server->req_lock);
 741                 return true;
 742         }
 743         spin_unlock(&server->req_lock);
 744         return false;
 745 }
 746
 747 static int
 748 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
 749 {
 750         int length = 0;
 751         int total_read;
 752
 753         smb_msg->msg_control = NULL;
 754         smb_msg->msg_controllen = 0;
 755
 756         for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
 757                 try_to_freeze();
 758
 759                 /* reconnect if no credits and no requests in flight */
 760                 if (zero_credits(server)) {
 761                         cifs_reconnect(server);
 762                         return -ECONNABORTED;
 763                 }
 764
 765                 if (server_unresponsive(server))
 766                         return -ECONNABORTED;
 767                 if (cifs_rdma_enabled(server) && server->smbd_conn)
 768                         length = smbd_recv(server->smbd_conn, smb_msg);
 769                 else
 770                         length = sock_recvmsg(server->ssocket, smb_msg, 0);
 771
 772                 if (server->tcpStatus == CifsExiting)
 773                         return -ESHUTDOWN;
 774
 775                 if (server->tcpStatus == CifsNeedReconnect) {
 776                         cifs_reconnect(server);
 777                         return -ECONNABORTED;
 778                 }
 779
 780                 if (length == -ERESTARTSYS ||
 781                     length == -EAGAIN ||
 782                     length == -EINTR) {
 783                         /*
 784                          * Minimum sleep to prevent looping, allowing socket
 785                          * to clear and app threads to set tcpStatus
 786                          * CifsNeedReconnect if server hung.
 787                          */
 788                         usleep_range(1000, 2000);
 789                         length = 0;
 790                         continue;
 791                 }
 792
 793                 if (length <= 0) {
 794                         cifs_dbg(FYI, "Received no data or error: %d\n", length);
 795                         cifs_reconnect(server);
 796                         return -ECONNABORTED;
 797                 }
 798         }
 799         return total_read;
 800 }
 801
 802 int
 803 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
 804                       unsigned int to_read)
 805 {
 806         struct msghdr smb_msg;
 807         struct kvec iov = {.iov_base = buf, .iov_len = to_read};
 808         iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
 809
 810         return cifs_readv_from_socket(server, &smb_msg);
 811 }
 812
 813 int
 814 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
 815         unsigned int page_offset, unsigned int to_read)
 816 {
 817         struct msghdr smb_msg;
 818         struct bio_vec bv = {
 819                 .bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
 820         iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
 821         return cifs_readv_from_socket(server, &smb_msg);
 822 }
 823
 824 static bool
 825 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
 826 {
 827         /*
 828          * The first byte big endian of the length field,
 829          * is actually not part of the length but the type
 830          * with the most common, zero, as regular data.
 831          */
 832         switch (type) {
 833         case RFC1002_SESSION_MESSAGE:
 834                 /* Regular SMB response */
 835                 return true;
 836         case RFC1002_SESSION_KEEP_ALIVE:
 837                 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
 838                 break;
 839         case RFC1002_POSITIVE_SESSION_RESPONSE:
 840                 cifs_dbg(FYI, "RFC 1002 positive session response\n");
 841                 break;
 842         case RFC1002_NEGATIVE_SESSION_RESPONSE:
 843                 /*
 844                  * We get this from Windows 98 instead of an error on
 845                  * SMB negprot response.
 846                  */
 847                 cifs_dbg(FYI, "RFC 1002 negative session response\n");
 848                 /* give server a second to clean up */
 849                 msleep(1000);
 850                 /*
 851                  * Always try 445 first on reconnect since we get NACK
 852                  * on some if we ever connected to port 139 (the NACK
 853                  * is since we do not begin with RFC1001 session
 854                  * initialize frame).
 855                  */
 856                 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
 857                 cifs_reconnect(server);
 858                 break;
 859         default:
 860                 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
 861                 cifs_reconnect(server);
 862         }
 863
 864         return false;
 865 }
 866
 867 void
 868 dequeue_mid(struct mid_q_entry *mid, bool malformed)
 869 {
 870 #ifdef CONFIG_CIFS_STATS2
 871         mid->when_received = jiffies;
 872 #endif
 873         spin_lock(&GlobalMid_Lock);
 874         if (!malformed)
 875                 mid->mid_state = MID_RESPONSE_RECEIVED;
 876         else
 877                 mid->mid_state = MID_RESPONSE_MALFORMED;
 878         /*
 879          * Trying to handle/dequeue a mid after the send_recv()
 880          * function has finished processing it is a bug.
 881          */
 882         if (mid->mid_flags & MID_DELETED)
 883                 pr_warn_once("trying to dequeue a deleted mid\n");
 884         else {
 885                 list_del_init(&mid->qhead);
 886                 mid->mid_flags |= MID_DELETED;
 887         }
 888         spin_unlock(&GlobalMid_Lock);
 889 }
 890
 891 static unsigned int
 892 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
 893 {
 894         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
 895
 896         /*
 897          * SMB1 does not use credits.
 898          */
 899         if (server->vals->header_preamble_size)
 900                 return 0;
 901
 902         return le16_to_cpu(shdr->CreditRequest);
 903 }
 904
 905 static void
 906 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 907            char *buf, int malformed)
 908 {
 909         if (server->ops->check_trans2 &&
 910             server->ops->check_trans2(mid, server, buf, malformed))
 911                 return;
 912         mid->credits_received = smb2_get_credits_from_hdr(buf, server);
 913         mid->resp_buf = buf;
 914         mid->large_buf = server->large_buf;
 915         /* Was previous buf put in mpx struct for multi-rsp? */
 916         if (!mid->multiRsp) {
 917                 /* smb buffer will be freed by user thread */
 918                 if (server->large_buf)
 919                         server->bigbuf = NULL;
 920                 else
 921                         server->smallbuf = NULL;
 922         }
 923         dequeue_mid(mid, malformed);
 924 }
 925
 926 static void clean_demultiplex_info(struct TCP_Server_Info *server)
 927 {
 928         int length;
 929
 930         /* take it off the list, if it's not already */
 931         spin_lock(&cifs_tcp_ses_lock);
 932         list_del_init(&server->tcp_ses_list);
 933         spin_unlock(&cifs_tcp_ses_lock);
 934
 935         spin_lock(&GlobalMid_Lock);
 936         server->tcpStatus = CifsExiting;
 937         spin_unlock(&GlobalMid_Lock);
 938         wake_up_all(&server->response_q);
 939
 940         /* check if we have blocked requests that need to free */
 941         spin_lock(&server->req_lock);
 942         if (server->credits <= 0)
 943                 server->credits = 1;
 944         spin_unlock(&server->req_lock);
 945         /*
 946          * Although there should not be any requests blocked on this queue it
 947          * can not hurt to be paranoid and try to wake up requests that may
 948          * haven been blocked when more than 50 at time were on the wire to the
 949          * same server - they now will see the session is in exit state and get
 950          * out of SendReceive.
 951          */
 952         wake_up_all(&server->request_q);
 953         /* give those requests time to exit */
 954         msleep(125);
 955         if (cifs_rdma_enabled(server))
 956                 smbd_destroy(server);
 957         if (server->ssocket) {
 958                 sock_release(server->ssocket);
 959                 server->ssocket = NULL;
 960         }
 961
 962         if (!list_empty(&server->pending_mid_q)) {
 963                 struct list_head dispose_list;
 964                 struct mid_q_entry *mid_entry;
 965                 struct list_head *tmp, *tmp2;
 966
 967                 INIT_LIST_HEAD(&dispose_list);
 968                 spin_lock(&GlobalMid_Lock);
 969                 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
 970                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 971                         cifs_dbg(FYI, "Clearing mid 0x%llx\n", mid_entry->mid);
 972                         kref_get(&mid_entry->refcount);
 973                         mid_entry->mid_state = MID_SHUTDOWN;
 974                         list_move(&mid_entry->qhead, &dispose_list);
 975                         mid_entry->mid_flags |= MID_DELETED;
 976                 }
 977                 spin_unlock(&GlobalMid_Lock);
 978
 979                 /* now walk dispose list and issue callbacks */
 980                 list_for_each_safe(tmp, tmp2, &dispose_list) {
 981                         mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
 982                         cifs_dbg(FYI, "Callback mid 0x%llx\n", mid_entry->mid);
 983                         list_del_init(&mid_entry->qhead);
 984                         mid_entry->callback(mid_entry);
 985                         cifs_mid_q_entry_release(mid_entry);
 986                 }
 987                 /* 1/8th of sec is more than enough time for them to exit */
 988                 msleep(125);
 989         }
 990
 991         if (!list_empty(&server->pending_mid_q)) {
 992                 /*
 993                  * mpx threads have not exited yet give them at least the smb
 994                  * send timeout time for long ops.
 995                  *
 996                  * Due to delays on oplock break requests, we need to wait at
 997                  * least 45 seconds before giving up on a request getting a
 998                  * response and going ahead and killing cifsd.
 999                  */
1000                 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
1001                 msleep(46000);
1002                 /*
1003                  * If threads still have not exited they are probably never
1004                  * coming home not much else we can do but free the memory.
1005                  */
1006         }
1007
1008         kfree(server->hostname);
1009         kfree(server);
1010
1011         length = atomic_dec_return(&tcpSesAllocCount);
1012         if (length > 0)
1013                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1014 }
1015
1016 static int
1017 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1018 {
1019         int length;
1020         char *buf = server->smallbuf;
1021         unsigned int pdu_length = server->pdu_size;
1022
1023         /* make sure this will fit in a large buffer */
1024         if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1025                 server->vals->header_preamble_size) {
1026                 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1027                 cifs_reconnect(server);
1028                 return -ECONNABORTED;
1029         }
1030
1031         /* switch to large buffer if too big for a small one */
1032         if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1033                 server->large_buf = true;
1034                 memcpy(server->bigbuf, buf, server->total_read);
1035                 buf = server->bigbuf;
1036         }
1037
1038         /* now read the rest */
1039         length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1040                                        pdu_length - HEADER_SIZE(server) + 1
1041                                        + server->vals->header_preamble_size);
1042
1043         if (length < 0)
1044                 return length;
1045         server->total_read += length;
1046
1047         dump_smb(buf, server->total_read);
1048
1049         return cifs_handle_standard(server, mid);
1050 }
1051
1052 int
1053 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1054 {
1055         char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1056         int length;
1057
1058         /*
1059          * We know that we received enough to get to the MID as we
1060          * checked the pdu_length earlier. Now check to see
1061          * if the rest of the header is OK. We borrow the length
1062          * var for the rest of the loop to avoid a new stack var.
1063          *
1064          * 48 bytes is enough to display the header and a little bit
1065          * into the payload for debugging purposes.
1066          */
1067         length = server->ops->check_message(buf, server->total_read, server);
1068         if (length != 0)
1069                 cifs_dump_mem("Bad SMB: ", buf,
1070                         min_t(unsigned int, server->total_read, 48));
1071
1072         if (server->ops->is_session_expired &&
1073             server->ops->is_session_expired(buf)) {
1074                 cifs_reconnect(server);
1075                 return -1;
1076         }
1077
1078         if (server->ops->is_status_pending &&
1079             server->ops->is_status_pending(buf, server))
1080                 return -1;
1081
1082         if (!mid)
1083                 return length;
1084
1085         handle_mid(mid, server, buf, length);
1086         return 0;
1087 }
1088
1089 static void
1090 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1091 {
1092         struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
1093
1094         /*
1095          * SMB1 does not use credits.
1096          */
1097         if (server->vals->header_preamble_size)
1098                 return;
1099
1100         if (shdr->CreditRequest) {
1101                 spin_lock(&server->req_lock);
1102                 server->credits += le16_to_cpu(shdr->CreditRequest);
1103                 spin_unlock(&server->req_lock);
1104                 wake_up(&server->request_q);
1105         }
1106 }
1107
1108
1109 static int
1110 cifs_demultiplex_thread(void *p)
1111 {
1112         int i, num_mids, length;
1113         struct TCP_Server_Info *server = p;
1114         unsigned int pdu_length;
1115         unsigned int next_offset;
1116         char *buf = NULL;
1117         struct task_struct *task_to_wake = NULL;
1118         struct mid_q_entry *mids[MAX_COMPOUND];
1119         char *bufs[MAX_COMPOUND];
1120         unsigned int noreclaim_flag;
1121
1122         noreclaim_flag = memalloc_noreclaim_save();
1123         cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1124
1125         length = atomic_inc_return(&tcpSesAllocCount);
1126         if (length > 1)
1127                 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1128
1129         set_freezable();
1130         allow_kernel_signal(SIGKILL);
1131         while (server->tcpStatus != CifsExiting) {
1132                 if (try_to_freeze())
1133                         continue;
1134
1135                 if (!allocate_buffers(server))
1136                         continue;
1137
1138                 server->large_buf = false;
1139                 buf = server->smallbuf;
1140                 pdu_length = 4; /* enough to get RFC1001 header */
1141
1142                 length = cifs_read_from_socket(server, buf, pdu_length);
1143                 if (length < 0)
1144                         continue;
1145
1146                 if (server->vals->header_preamble_size == 0)
1147                         server->total_read = 0;
1148                 else
1149                         server->total_read = length;
1150
1151                 /*
1152                  * The right amount was read from socket - 4 bytes,
1153                  * so we can now interpret the length field.
1154                  */
1155                 pdu_length = get_rfc1002_length(buf);
1156
1157                 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1158                 if (!is_smb_response(server, buf[0]))
1159                         continue;
1160 next_pdu:
1161                 server->pdu_size = pdu_length;
1162
1163                 /* make sure we have enough to get to the MID */
1164                 if (server->pdu_size < HEADER_SIZE(server) - 1 -
1165                     server->vals->header_preamble_size) {
1166                         cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1167                                  server->pdu_size);
1168                         cifs_reconnect(server);
1169                         continue;
1170                 }
1171
1172                 /* read down to the MID */
1173                 length = cifs_read_from_socket(server,
1174                              buf + server->vals->header_preamble_size,
1175                              HEADER_SIZE(server) - 1
1176                              - server->vals->header_preamble_size);
1177                 if (length < 0)
1178                         continue;
1179                 server->total_read += length;
1180
1181                 if (server->ops->next_header) {
1182                         next_offset = server->ops->next_header(buf);
1183                         if (next_offset)
1184                                 server->pdu_size = next_offset;
1185                 }
1186
1187                 memset(mids, 0, sizeof(mids));
1188                 memset(bufs, 0, sizeof(bufs));
1189                 num_mids = 0;
1190
1191                 if (server->ops->is_transform_hdr &&
1192                     server->ops->receive_transform &&
1193                     server->ops->is_transform_hdr(buf)) {
1194                         length = server->ops->receive_transform(server,
1195                                                                 mids,
1196                                                                 bufs,
1197                                                                 &num_mids);
1198                 } else {
1199                         mids[0] = server->ops->find_mid(server, buf);
1200                         bufs[0] = buf;
1201                         num_mids = 1;
1202
1203                         if (!mids[0] || !mids[0]->receive)
1204                                 length = standard_receive3(server, mids[0]);
1205                         else
1206                                 length = mids[0]->receive(server, mids[0]);
1207                 }
1208
1209                 if (length < 0) {
1210                         for (i = 0; i < num_mids; i++)
1211                                 if (mids[i])
1212                                         cifs_mid_q_entry_release(mids[i]);
1213                         continue;
1214                 }
1215
1216                 server->lstrp = jiffies;
1217
1218                 for (i = 0; i < num_mids; i++) {
1219                         if (mids[i] != NULL) {
1220                                 mids[i]->resp_buf_size = server->pdu_size;
1221
1222                                 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1223                                         mids[i]->callback(mids[i]);
1224
1225                                 cifs_mid_q_entry_release(mids[i]);
1226                         } else if (server->ops->is_oplock_break &&
1227                                    server->ops->is_oplock_break(bufs[i],
1228                                                                 server)) {
1229                                 smb2_add_credits_from_hdr(bufs[i], server);
1230                                 cifs_dbg(FYI, "Received oplock break\n");
1231                         } else {
1232                                 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1233                                                 atomic_read(&midCount));
1234                                 cifs_dump_mem("Received Data is: ", bufs[i],
1235                                               HEADER_SIZE(server));
1236                                 smb2_add_credits_from_hdr(bufs[i], server);
1237 #ifdef CONFIG_CIFS_DEBUG2
1238                                 if (server->ops->dump_detail)
1239                                         server->ops->dump_detail(bufs[i],
1240                                                                  server);
1241                                 cifs_dump_mids(server);
1242 #endif /* CIFS_DEBUG2 */
1243                         }
1244                 }
1245
1246                 if (pdu_length > server->pdu_size) {
1247                         if (!allocate_buffers(server))
1248                                 continue;
1249                         pdu_length -= server->pdu_size;
1250                         server->total_read = 0;
1251                         server->large_buf = false;
1252                         buf = server->smallbuf;
1253                         goto next_pdu;
1254                 }
1255         } /* end while !EXITING */
1256
1257         /* buffer usually freed in free_mid - need to free it here on exit */
1258         cifs_buf_release(server->bigbuf);
1259         if (server->smallbuf) /* no sense logging a debug message if NULL */
1260                 cifs_small_buf_release(server->smallbuf);
1261
1262         task_to_wake = xchg(&server->tsk, NULL);
1263         clean_demultiplex_info(server);
1264
1265         /* if server->tsk was NULL then wait for a signal before exiting */
1266         if (!task_to_wake) {
1267                 set_current_state(TASK_INTERRUPTIBLE);
1268                 while (!signal_pending(current)) {
1269                         schedule();
1270                         set_current_state(TASK_INTERRUPTIBLE);
1271                 }
1272                 set_current_state(TASK_RUNNING);
1273         }
1274
1275         memalloc_noreclaim_restore(noreclaim_flag);
1276         module_put_and_exit(0);
1277 }
1278
1279 /* extract the host portion of the UNC string */
1280 static char *
1281 extract_hostname(const char *unc)
1282 {
1283         const char *src;
1284         char *dst, *delim;
1285         unsigned int len;
1286
1287         /* skip double chars at beginning of string */
1288         /* BB: check validity of these bytes? */
1289         if (strlen(unc) < 3)
1290                 return ERR_PTR(-EINVAL);
1291         for (src = unc; *src && *src == '\\'; src++)
1292                 ;
1293         if (!*src)
1294                 return ERR_PTR(-EINVAL);
1295
1296         /* delimiter between hostname and sharename is always '\\' now */
1297         delim = strchr(src, '\\');
1298         if (!delim)
1299                 return ERR_PTR(-EINVAL);
1300
1301         len = delim - src;
1302         dst = kmalloc((len + 1), GFP_KERNEL);
1303         if (dst == NULL)
1304                 return ERR_PTR(-ENOMEM);
1305
1306         memcpy(dst, src, len);
1307         dst[len] = '\0';
1308
1309         return dst;
1310 }
1311
1312 static int get_option_ul(substring_t args[], unsigned long *option)
1313 {
1314         int rc;
1315         char *string;
1316
1317         string = match_strdup(args);
1318         if (string == NULL)
1319                 return -ENOMEM;
1320         rc = kstrtoul(string, 0, option);
1321         kfree(string);
1322
1323         return rc;
1324 }
1325
1326 static int get_option_uid(substring_t args[], kuid_t *result)
1327 {
1328         unsigned long value;
1329         kuid_t uid;
1330         int rc;
1331
1332         rc = get_option_ul(args, &value);
1333         if (rc)
1334                 return rc;
1335
1336         uid = make_kuid(current_user_ns(), value);
1337         if (!uid_valid(uid))
1338                 return -EINVAL;
1339
1340         *result = uid;
1341         return 0;
1342 }
1343
1344 static int get_option_gid(substring_t args[], kgid_t *result)
1345 {
1346         unsigned long value;
1347         kgid_t gid;
1348         int rc;
1349
1350         rc = get_option_ul(args, &value);
1351         if (rc)
1352                 return rc;
1353
1354         gid = make_kgid(current_user_ns(), value);
1355         if (!gid_valid(gid))
1356                 return -EINVAL;
1357
1358         *result = gid;
1359         return 0;
1360 }
1361
1362 static int cifs_parse_security_flavors(char *value,
1363                                        struct smb_vol *vol)
1364 {
1365
1366         substring_t args[MAX_OPT_ARGS];
1367
1368         /*
1369          * With mount options, the last one should win. Reset any existing
1370          * settings back to default.
1371          */
1372         vol->sectype = Unspecified;
1373         vol->sign = false;
1374
1375         switch (match_token(value, cifs_secflavor_tokens, args)) {
1376         case Opt_sec_krb5p:
1377                 cifs_dbg(VFS, "sec=krb5p is not supported!\n");
1378                 return 1;
1379         case Opt_sec_krb5i:
1380                 vol->sign = true;
1381                 fallthrough;
1382         case Opt_sec_krb5:
1383                 vol->sectype = Kerberos;
1384                 break;
1385         case Opt_sec_ntlmsspi:
1386                 vol->sign = true;
1387                 fallthrough;
1388         case Opt_sec_ntlmssp:
1389                 vol->sectype = RawNTLMSSP;
1390                 break;
1391         case Opt_sec_ntlmi:
1392                 vol->sign = true;
1393                 fallthrough;
1394         case Opt_ntlm:
1395                 vol->sectype = NTLM;
1396                 break;
1397         case Opt_sec_ntlmv2i:
1398                 vol->sign = true;
1399                 fallthrough;
1400         case Opt_sec_ntlmv2:
1401                 vol->sectype = NTLMv2;
1402                 break;
1403 #ifdef CONFIG_CIFS_WEAK_PW_HASH
1404         case Opt_sec_lanman:
1405                 vol->sectype = LANMAN;
1406                 break;
1407 #endif
1408         case Opt_sec_none:
1409                 vol->nullauth = 1;
1410                 break;
1411         default:
1412                 cifs_dbg(VFS, "bad security option: %s\n", value);
1413                 return 1;
1414         }
1415
1416         return 0;
1417 }
1418
1419 static int
1420 cifs_parse_cache_flavor(char *value, struct smb_vol *vol)
1421 {
1422         substring_t args[MAX_OPT_ARGS];
1423
1424         switch (match_token(value, cifs_cacheflavor_tokens, args)) {
1425         case Opt_cache_loose:
1426                 vol->direct_io = false;
1427                 vol->strict_io = false;
1428                 vol->cache_ro = false;
1429                 vol->cache_rw = false;
1430                 break;
1431         case Opt_cache_strict:
1432                 vol->direct_io = false;
1433                 vol->strict_io = true;
1434                 vol->cache_ro = false;
1435                 vol->cache_rw = false;
1436                 break;
1437         case Opt_cache_none:
1438                 vol->direct_io = true;
1439                 vol->strict_io = false;
1440                 vol->cache_ro = false;
1441                 vol->cache_rw = false;
1442                 break;
1443         case Opt_cache_ro:
1444                 vol->direct_io = false;
1445                 vol->strict_io = false;
1446                 vol->cache_ro = true;
1447                 vol->cache_rw = false;
1448                 break;
1449         case Opt_cache_rw:
1450                 vol->direct_io = false;
1451                 vol->strict_io = false;
1452                 vol->cache_ro = false;
1453                 vol->cache_rw = true;
1454                 break;
1455         default:
1456                 cifs_dbg(VFS, "bad cache= option: %s\n", value);
1457                 return 1;
1458         }
1459         return 0;
1460 }
1461
1462 static int
1463 cifs_parse_smb_version(char *value, struct smb_vol *vol, bool is_smb3)
1464 {
1465         substring_t args[MAX_OPT_ARGS];
1466
1467         switch (match_token(value, cifs_smb_version_tokens, args)) {
1468 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
1469         case Smb_1:
1470                 if (disable_legacy_dialects) {
1471                         cifs_dbg(VFS, "mount with legacy dialect disabled\n");
1472                         return 1;
1473                 }
1474                 if (is_smb3) {
1475                         cifs_dbg(VFS, "vers=1.0 (cifs) not permitted when mounting with smb3\n");
1476                         return 1;
1477                 }
1478                 cifs_dbg(VFS, "Use of the less secure dialect vers=1.0 is not recommended unless required for access to very old servers\n");
1479                 vol->ops = &smb1_operations;
1480                 vol->vals = &smb1_values;
1481                 break;
1482         case Smb_20:
1483                 if (disable_legacy_dialects) {
1484                         cifs_dbg(VFS, "mount with legacy dialect disabled\n");
1485                         return 1;
1486                 }
1487                 if (is_smb3) {
1488                         cifs_dbg(VFS, "vers=2.0 not permitted when mounting with smb3\n");
1489                         return 1;
1490                 }
1491                 vol->ops = &smb20_operations;
1492                 vol->vals = &smb20_values;
1493                 break;
1494 #else
1495         case Smb_1:
1496                 cifs_dbg(VFS, "vers=1.0 (cifs) mount not permitted when legacy dialects disabled\n");
1497                 return 1;
1498         case Smb_20:
1499                 cifs_dbg(VFS, "vers=2.0 mount not permitted when legacy dialects disabled\n");
1500                 return 1;
1501 #endif /* CIFS_ALLOW_INSECURE_LEGACY */
1502         case Smb_21:
1503                 vol->ops = &smb21_operations;
1504                 vol->vals = &smb21_values;
1505                 break;
1506         case Smb_30:
1507                 vol->ops = &smb30_operations;
1508                 vol->vals = &smb30_values;
1509                 break;
1510         case Smb_302:
1511                 vol->ops = &smb30_operations; /* currently identical with 3.0 */
1512                 vol->vals = &smb302_values;
1513                 break;
1514         case Smb_311:
1515                 vol->ops = &smb311_operations;
1516                 vol->vals = &smb311_values;
1517                 break;
1518         case Smb_3any:
1519                 vol->ops = &smb30_operations; /* currently identical with 3.0 */
1520                 vol->vals = &smb3any_values;
1521                 break;
1522         case Smb_default:
1523                 vol->ops = &smb30_operations; /* currently identical with 3.0 */
1524                 vol->vals = &smbdefault_values;
1525                 break;
1526         default:
1527                 cifs_dbg(VFS, "Unknown vers= option specified: %s\n", value);
1528                 return 1;
1529         }
1530         return 0;
1531 }
1532
1533 /*
1534  * Parse a devname into substrings and populate the vol->UNC and vol->prepath
1535  * fields with the result. Returns 0 on success and an error otherwise.
1536  */
1537 static int
1538 cifs_parse_devname(const char *devname, struct smb_vol *vol)
1539 {
1540         char *pos;
1541         const char *delims = "/\\";
1542         size_t len;
1543
1544         if (unlikely(!devname || !*devname)) {
1545                 cifs_dbg(VFS, "Device name not specified\n");
1546                 return -EINVAL;
1547         }
1548
1549         /* make sure we have a valid UNC double delimiter prefix */
1550         len = strspn(devname, delims);
1551         if (len != 2)
1552                 return -EINVAL;
1553
1554         /* find delimiter between host and sharename */
1555         pos = strpbrk(devname + 2, delims);
1556         if (!pos)
1557                 return -EINVAL;
1558
1559         /* skip past delimiter */
1560         ++pos;
1561
1562         /* now go until next delimiter or end of string */
1563         len = strcspn(pos, delims);
1564
1565         /* move "pos" up to delimiter or NULL */
1566         pos += len;
1567         vol->UNC = kstrndup(devname, pos - devname, GFP_KERNEL);
1568         if (!vol->UNC)
1569                 return -ENOMEM;
1570
1571         convert_delimiter(vol->UNC, '\\');
1572
1573         /* skip any delimiter */
1574         if (*pos == '/' || *pos == '\\')
1575                 pos++;
1576
1577         /* If pos is NULL then no prepath */
1578         if (!*pos)
1579                 return 0;
1580
1581         vol->prepath = kstrdup(pos, GFP_KERNEL);
1582         if (!vol->prepath)
1583                 return -ENOMEM;
1584
1585         return 0;
1586 }
1587
1588 static int
1589 cifs_parse_mount_options(const char *mountdata, const char *devname,
1590                          struct smb_vol *vol, bool is_smb3)
1591 {
1592         char *data, *end;
1593         char *mountdata_copy = NULL, *options;
1594         unsigned int  temp_len, i, j;
1595         char separator[2];
1596         short int override_uid = -1;
1597         short int override_gid = -1;
1598         bool uid_specified = false;
1599         bool gid_specified = false;
1600         bool sloppy = false;
1601         char *invalid = NULL;
1602         char *nodename = utsname()->nodename;
1603         char *string = NULL;
1604         char *tmp_end, *value;
1605         char delim;
1606         bool got_ip = false;
1607         bool got_version = false;
1608         unsigned short port = 0;
1609         struct sockaddr *dstaddr = (struct sockaddr *)&vol->dstaddr;
1610
1611         separator[0] = ',';
1612         separator[1] = 0;
1613         delim = separator[0];
1614
1615         /* ensure we always start with zeroed-out smb_vol */
1616         memset(vol, 0, sizeof(*vol));
1617
1618         /*
1619          * does not have to be perfect mapping since field is
1620          * informational, only used for servers that do not support
1621          * port 445 and it can be overridden at mount time
1622          */
1623         memset(vol->source_rfc1001_name, 0x20, RFC1001_NAME_LEN);
1624         for (i = 0; i < strnlen(nodename, RFC1001_NAME_LEN); i++)
1625                 vol->source_rfc1001_name[i] = toupper(nodename[i]);
1626
1627         vol->source_rfc1001_name[RFC1001_NAME_LEN] = 0;
1628         /* null target name indicates to use *SMBSERVR default called name
1629            if we end up sending RFC1001 session initialize */
1630         vol->target_rfc1001_name[0] = 0;
1631         vol->cred_uid = current_uid();
1632         vol->linux_uid = current_uid();
1633         vol->linux_gid = current_gid();
1634         vol->bsize = 1024 * 1024; /* can improve cp performance significantly */
1635         /*
1636          * default to SFM style remapping of seven reserved characters
1637          * unless user overrides it or we negotiate CIFS POSIX where
1638          * it is unnecessary.  Can not simultaneously use more than one mapping
1639          * since then readdir could list files that open could not open
1640          */
1641         vol->remap = true;
1642
1643         /* default to only allowing write access to owner of the mount */
1644         vol->dir_mode = vol->file_mode = S_IRUGO | S_IXUGO | S_IWUSR;
1645
1646         /* vol->retry default is 0 (i.e. "soft" limited retry not hard retry) */
1647         /* default is always to request posix paths. */
1648         vol->posix_paths = 1;
1649         /* default to using server inode numbers where available */
1650         vol->server_ino = 1;
1651
1652         /* default is to use strict cifs caching semantics */
1653         vol->strict_io = true;
1654
1655         vol->actimeo = CIFS_DEF_ACTIMEO;
1656
1657         /* Most clients set timeout to 0, allows server to use its default */
1658         vol->handle_timeout = 0; /* See MS-SMB2 spec section 2.2.14.2.12 */
1659
1660         /* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */
1661         vol->ops = &smb30_operations;
1662         vol->vals = &smbdefault_values;
1663
1664         vol->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
1665
1666         /* default to no multichannel (single server connection) */
1667         vol->multichannel = false;
1668         vol->max_channels = 1;
1669
1670         if (!mountdata)
1671                 goto cifs_parse_mount_err;
1672
1673         mountdata_copy = kstrndup(mountdata, PAGE_SIZE, GFP_KERNEL);
1674         if (!mountdata_copy)
1675                 goto cifs_parse_mount_err;
1676
1677         options = mountdata_copy;
1678         end = options + strlen(options);
1679
1680         if (strncmp(options, "sep=", 4) == 0) {
1681                 if (options[4] != 0) {
1682                         separator[0] = options[4];
1683                         options += 5;
1684                 } else {
1685                         cifs_dbg(FYI, "Null separator not allowed\n");
1686                 }
1687         }
1688         vol->backupuid_specified = false; /* no backup intent for a user */
1689         vol->backupgid_specified = false; /* no backup intent for a group */
1690
1691         switch (cifs_parse_devname(devname, vol)) {
1692         case 0:
1693                 break;
1694         case -ENOMEM:
1695                 cifs_dbg(VFS, "Unable to allocate memory for devname\n");
1696                 goto cifs_parse_mount_err;
1697         case -EINVAL:
1698                 cifs_dbg(VFS, "Malformed UNC in devname\n");
1699                 goto cifs_parse_mount_err;
1700         default:
1701                 cifs_dbg(VFS, "Unknown error parsing devname\n");
1702                 goto cifs_parse_mount_err;
1703         }
1704
1705         while ((data = strsep(&options, separator)) != NULL) {
1706                 substring_t args[MAX_OPT_ARGS];
1707                 unsigned long option;
1708                 int token;
1709
1710                 if (!*data)
1711                         continue;
1712
1713                 token = match_token(data, cifs_mount_option_tokens, args);
1714
1715                 switch (token) {
1716
1717                 /* Ingnore the following */
1718                 case Opt_ignore:
1719                         break;
1720
1721                 /* Boolean values */
1722                 case Opt_user_xattr:
1723                         vol->no_xattr = 0;
1724                         break;
1725                 case Opt_nouser_xattr:
1726                         vol->no_xattr = 1;
1727                         break;
1728                 case Opt_forceuid:
1729                         override_uid = 1;
1730                         break;
1731                 case Opt_noforceuid:
1732                         override_uid = 0;
1733                         break;
1734                 case Opt_forcegid:
1735                         override_gid = 1;
1736                         break;
1737                 case Opt_noforcegid:
1738                         override_gid = 0;
1739                         break;
1740                 case Opt_noblocksend:
1741                         vol->noblocksnd = 1;
1742                         break;
1743                 case Opt_noautotune:
1744                         vol->noautotune = 1;
1745                         break;
1746                 case Opt_nolease:
1747                         vol->no_lease = 1;
1748                         break;
1749                 case Opt_hard:
1750                         vol->retry = 1;
1751                         break;
1752                 case Opt_soft:
1753                         vol->retry = 0;
1754                         break;
1755                 case Opt_perm:
1756                         vol->noperm = 0;
1757                         break;
1758                 case Opt_noperm:
1759                         vol->noperm = 1;
1760                         break;
1761                 case Opt_nodelete:
1762                         vol->nodelete = 1;
1763                         break;
1764                 case Opt_mapchars:
1765                         vol->sfu_remap = true;
1766                         vol->remap = false; /* disable SFM mapping */
1767                         break;
1768                 case Opt_nomapchars:
1769                         vol->sfu_remap = false;
1770                         break;
1771                 case Opt_mapposix:
1772                         vol->remap = true;
1773                         vol->sfu_remap = false; /* disable SFU mapping */
1774                         break;
1775                 case Opt_nomapposix:
1776                         vol->remap = false;
1777                         break;
1778                 case Opt_sfu:
1779                         vol->sfu_emul = 1;
1780                         break;
1781                 case Opt_nosfu:
1782                         vol->sfu_emul = 0;
1783                         break;
1784                 case Opt_nodfs:
1785                         vol->nodfs = 1;
1786                         break;
1787                 case Opt_rootfs:
1788 #ifdef CONFIG_CIFS_ROOT
1789                         vol->rootfs = true;
1790 #endif
1791                         break;
1792                 case Opt_posixpaths:
1793                         vol->posix_paths = 1;
1794                         break;
1795                 case Opt_noposixpaths:
1796                         vol->posix_paths = 0;
1797                         break;
1798                 case Opt_nounix:
1799                         if (vol->linux_ext)
1800                                 cifs_dbg(VFS,
1801                                         "conflicting unix mount options\n");
1802                         vol->no_linux_ext = 1;
1803                         break;
1804                 case Opt_unix:
1805                         if (vol->no_linux_ext)
1806                                 cifs_dbg(VFS,
1807                                         "conflicting unix mount options\n");
1808                         vol->linux_ext = 1;
1809                         break;
1810                 case Opt_nocase:
1811                         vol->nocase = 1;
1812                         break;
1813                 case Opt_brl:
1814                         vol->nobrl =  0;
1815                         break;
1816                 case Opt_nobrl:
1817                         vol->nobrl =  1;
1818                         /*
1819                          * turn off mandatory locking in mode
1820                          * if remote locking is turned off since the
1821                          * local vfs will do advisory
1822                          */
1823                         if (vol->file_mode ==
1824                                 (S_IALLUGO & ~(S_ISUID | S_IXGRP)))
1825                                 vol->file_mode = S_IALLUGO;
1826                         break;
1827                 case Opt_nohandlecache:
1828                         vol->nohandlecache = 1;
1829                         break;
1830                 case Opt_handlecache:
1831                         vol->nohandlecache = 0;
1832                         break;
1833                 case Opt_forcemandatorylock:
1834                         vol->mand_lock = 1;
1835                         break;
1836                 case Opt_setuids:
1837                         vol->setuids = 1;
1838                         break;
1839                 case Opt_nosetuids:
1840                         vol->setuids = 0;
1841                         break;
1842                 case Opt_setuidfromacl:
1843                         vol->setuidfromacl = 1;
1844                         break;
1845                 case Opt_dynperm:
1846                         vol->dynperm = true;
1847                         break;
1848                 case Opt_nodynperm:
1849                         vol->dynperm = false;
1850                         break;
1851                 case Opt_nohard:
1852                         vol->retry = 0;
1853                         break;
1854                 case Opt_nosoft:
1855                         vol->retry = 1;
1856                         break;
1857                 case Opt_nointr:
1858                         vol->intr = 0;
1859                         break;
1860                 case Opt_intr:
1861                         vol->intr = 1;
1862                         break;
1863                 case Opt_nostrictsync:
1864                         vol->nostrictsync = 1;
1865                         break;
1866                 case Opt_strictsync:
1867                         vol->nostrictsync = 0;
1868                         break;
1869                 case Opt_serverino:
1870                         vol->server_ino = 1;
1871                         break;
1872                 case Opt_noserverino:
1873                         vol->server_ino = 0;
1874                         break;
1875                 case Opt_rwpidforward:
1876                         vol->rwpidforward = 1;
1877                         break;
1878                 case Opt_modesid:
1879                         vol->mode_ace = 1;
1880                         break;
1881                 case Opt_cifsacl:
1882                         vol->cifs_acl = 1;
1883                         break;
1884                 case Opt_nocifsacl:
1885                         vol->cifs_acl = 0;
1886                         break;
1887                 case Opt_acl:
1888                         vol->no_psx_acl = 0;
1889                         break;
1890                 case Opt_noacl:
1891                         vol->no_psx_acl = 1;
1892                         break;
1893                 case Opt_locallease:
1894                         vol->local_lease = 1;
1895                         break;
1896                 case Opt_sign:
1897                         vol->sign = true;
1898                         break;
1899                 case Opt_ignore_signature:
1900                         vol->sign = true;
1901                         vol->ignore_signature = true;
1902                         break;
1903                 case Opt_seal:
1904                         /* we do not do the following in secFlags because seal
1905                          * is a per tree connection (mount) not a per socket
1906                          * or per-smb connection option in the protocol
1907                          * vol->secFlg |= CIFSSEC_MUST_SEAL;
1908                          */
1909                         vol->seal = 1;
1910                         break;
1911                 case Opt_noac:
1912                         pr_warn("Mount option noac not supported. Instead set /proc/fs/cifs/LookupCacheEnabled to 0\n");
1913                         break;
1914                 case Opt_fsc:
1915 #ifndef CONFIG_CIFS_FSCACHE
1916                         cifs_dbg(VFS, "FS-Cache support needs CONFIG_CIFS_FSCACHE kernel config option set\n");
1917                         goto cifs_parse_mount_err;
1918 #endif
1919                         vol->fsc = true;
1920                         break;
1921                 case Opt_mfsymlinks:
1922                         vol->mfsymlinks = true;
1923                         break;
1924                 case Opt_multiuser:
1925                         vol->multiuser = true;
1926                         break;
1927                 case Opt_sloppy:
1928                         sloppy = true;
1929                         break;
1930                 case Opt_nosharesock:
1931                         vol->nosharesock = true;
1932                         break;
1933                 case Opt_nopersistent:
1934                         vol->nopersistent = true;
1935                         if (vol->persistent) {
1936                                 cifs_dbg(VFS,
1937                                   "persistenthandles mount options conflict\n");
1938                                 goto cifs_parse_mount_err;
1939                         }
1940                         break;
1941                 case Opt_persistent:
1942                         vol->persistent = true;
1943                         if ((vol->nopersistent) || (vol->resilient)) {
1944                                 cifs_dbg(VFS,
1945                                   "persistenthandles mount options conflict\n");
1946                                 goto cifs_parse_mount_err;
1947                         }
1948                         break;
1949                 case Opt_resilient:
1950                         vol->resilient = true;
1951                         if (vol->persistent) {
1952                                 cifs_dbg(VFS,
1953                                   "persistenthandles mount options conflict\n");
1954                                 goto cifs_parse_mount_err;
1955                         }
1956                         break;
1957                 case Opt_noresilient:
1958                         vol->resilient = false; /* already the default */
1959                         break;
1960                 case Opt_domainauto:
1961                         vol->domainauto = true;
1962                         break;
1963                 case Opt_rdma:
1964                         vol->rdma = true;
1965                         break;
1966                 case Opt_multichannel:
1967                         vol->multichannel = true;
1968                         /* if number of channels not specified, default to 2 */
1969                         if (vol->max_channels < 2)
1970                                 vol->max_channels = 2;
1971                         break;
1972                 case Opt_nomultichannel:
1973                         vol->multichannel = false;
1974                         vol->max_channels = 1;
1975                         break;
1976                 case Opt_compress:
1977                         vol->compression = UNKNOWN_TYPE;
1978                         cifs_dbg(VFS,
1979                                 "SMB3 compression support is experimental\n");
1980                         break;
1981
1982                 /* Numeric Values */
1983                 case Opt_backupuid:
1984                         if (get_option_uid(args, &vol->backupuid)) {
1985                                 cifs_dbg(VFS, "%s: Invalid backupuid value\n",
1986                                          __func__);
1987                                 goto cifs_parse_mount_err;
1988                         }
1989                         vol->backupuid_specified = true;
1990                         break;
1991                 case Opt_backupgid:
1992                         if (get_option_gid(args, &vol->backupgid)) {
1993                                 cifs_dbg(VFS, "%s: Invalid backupgid value\n",
1994                                          __func__);
1995                                 goto cifs_parse_mount_err;
1996                         }
1997                         vol->backupgid_specified = true;
1998                         break;
1999                 case Opt_uid:
2000                         if (get_option_uid(args, &vol->linux_uid)) {
2001                                 cifs_dbg(VFS, "%s: Invalid uid value\n",
2002                                          __func__);
2003                                 goto cifs_parse_mount_err;
2004                         }
2005                         uid_specified = true;
2006                         break;
2007                 case Opt_cruid:
2008                         if (get_option_uid(args, &vol->cred_uid)) {
2009                                 cifs_dbg(VFS, "%s: Invalid cruid value\n",
2010                                          __func__);
2011                                 goto cifs_parse_mount_err;
2012                         }
2013                         break;
2014                 case Opt_gid:
2015                         if (get_option_gid(args, &vol->linux_gid)) {
2016                                 cifs_dbg(VFS, "%s: Invalid gid value\n",
2017                                          __func__);
2018                                 goto cifs_parse_mount_err;
2019                         }
2020                         gid_specified = true;
2021                         break;
2022                 case Opt_file_mode:
2023                         if (get_option_ul(args, &option)) {
2024                                 cifs_dbg(VFS, "%s: Invalid file_mode value\n",
2025                                          __func__);
2026                                 goto cifs_parse_mount_err;
2027                         }
2028                         vol->file_mode = option;
2029                         break;
2030                 case Opt_dirmode:
2031                         if (get_option_ul(args, &option)) {
2032                                 cifs_dbg(VFS, "%s: Invalid dir_mode value\n",
2033                                          __func__);
2034                                 goto cifs_parse_mount_err;
2035                         }
2036                         vol->dir_mode = option;
2037                         break;
2038                 case Opt_port:
2039                         if (get_option_ul(args, &option) ||
2040                             option > USHRT_MAX) {
2041                                 cifs_dbg(VFS, "%s: Invalid port value\n",
2042                                          __func__);
2043                                 goto cifs_parse_mount_err;
2044                         }
2045                         port = (unsigned short)option;
2046                         break;
2047                 case Opt_min_enc_offload:
2048                         if (get_option_ul(args, &option)) {
2049                                 cifs_dbg(VFS, "Invalid minimum encrypted read offload size (esize)\n");
2050                                 goto cifs_parse_mount_err;
2051                         }
2052                         vol->min_offload = option;
2053                         break;
2054                 case Opt_blocksize:
2055                         if (get_option_ul(args, &option)) {
2056                                 cifs_dbg(VFS, "%s: Invalid blocksize value\n",
2057                                         __func__);
2058                                 goto cifs_parse_mount_err;
2059                         }
2060                         /*
2061                          * inode blocksize realistically should never need to be
2062                          * less than 16K or greater than 16M and default is 1MB.
2063                          * Note that small inode block sizes (e.g. 64K) can lead
2064                          * to very poor performance of common tools like cp and scp
2065                          */
2066                         if ((option < CIFS_MAX_MSGSIZE) ||
2067                            (option > (4 * SMB3_DEFAULT_IOSIZE))) {
2068                                 cifs_dbg(VFS, "%s: Invalid blocksize\n",
2069                                         __func__);
2070                                 goto cifs_parse_mount_err;
2071                         }
2072                         vol->bsize = option;
2073                         break;
2074                 case Opt_rsize:
2075                         if (get_option_ul(args, &option)) {
2076                                 cifs_dbg(VFS, "%s: Invalid rsize value\n",
2077                                          __func__);
2078                                 goto cifs_parse_mount_err;
2079                         }
2080                         vol->rsize = option;
2081                         break;
2082                 case Opt_wsize:
2083                         if (get_option_ul(args, &option)) {
2084                                 cifs_dbg(VFS, "%s: Invalid wsize value\n",
2085                                          __func__);
2086                                 goto cifs_parse_mount_err;
2087                         }
2088                         vol->wsize = option;
2089                         break;
2090                 case Opt_actimeo:
2091                         if (get_option_ul(args, &option)) {
2092                                 cifs_dbg(VFS, "%s: Invalid actimeo value\n",
2093                                          __func__);
2094                                 goto cifs_parse_mount_err;
2095                         }
2096                         vol->actimeo = HZ * option;
2097                         if (vol->actimeo > CIFS_MAX_ACTIMEO) {
2098                                 cifs_dbg(VFS, "attribute cache timeout too large\n");
2099                                 goto cifs_parse_mount_err;
2100                         }
2101                         break;
2102                 case Opt_handletimeout:
2103                         if (get_option_ul(args, &option)) {
2104                                 cifs_dbg(VFS, "%s: Invalid handletimeout value\n",
2105                                          __func__);
2106                                 goto cifs_parse_mount_err;
2107                         }
2108                         vol->handle_timeout = option;
2109                         if (vol->handle_timeout > SMB3_MAX_HANDLE_TIMEOUT) {
2110                                 cifs_dbg(VFS, "Invalid handle cache timeout, longer than 16 minutes\n");
2111                                 goto cifs_parse_mount_err;
2112                         }
2113                         break;
2114                 case Opt_echo_interval:
2115                         if (get_option_ul(args, &option)) {
2116                                 cifs_dbg(VFS, "%s: Invalid echo interval value\n",
2117                                          __func__);
2118                                 goto cifs_parse_mount_err;
2119                         }
2120                         vol->echo_interval = option;
2121                         break;
2122                 case Opt_snapshot:
2123                         if (get_option_ul(args, &option)) {
2124                                 cifs_dbg(VFS, "%s: Invalid snapshot time\n",
2125                                          __func__);
2126                                 goto cifs_parse_mount_err;
2127                         }
2128                         vol->snapshot_time = option;
2129                         break;
2130                 case Opt_max_credits:
2131                         if (get_option_ul(args, &option) || (option < 20) ||
2132                             (option > 60000)) {
2133                                 cifs_dbg(VFS, "%s: Invalid max_credits value\n",
2134                                          __func__);
2135                                 goto cifs_parse_mount_err;
2136                         }
2137                         vol->max_credits = option;
2138                         break;
2139                 case Opt_max_channels:
2140                         if (get_option_ul(args, &option) || option < 1 ||
2141                                 option > CIFS_MAX_CHANNELS) {
2142                                 cifs_dbg(VFS, "%s: Invalid max_channels value, needs to be 1-%d\n",
2143                                          __func__, CIFS_MAX_CHANNELS);
2144                                 goto cifs_parse_mount_err;
2145                         }
2146                         vol->max_channels = option;
2147                         break;
2148
2149                 /* String Arguments */
2150
2151                 case Opt_blank_user:
2152                         /* null user, ie. anonymous authentication */
2153                         vol->nullauth = 1;
2154                         vol->username = NULL;
2155                         break;
2156                 case Opt_user:
2157                         string = match_strdup(args);
2158                         if (string == NULL)
2159                                 goto out_nomem;
2160
2161                         if (strnlen(string, CIFS_MAX_USERNAME_LEN) >
2162                                                         CIFS_MAX_USERNAME_LEN) {
2163                                 pr_warn("username too long\n");
2164                                 goto cifs_parse_mount_err;
2165                         }
2166
2167                         kfree(vol->username);
2168                         vol->username = kstrdup(string, GFP_KERNEL);
2169                         if (!vol->username)
2170                                 goto cifs_parse_mount_err;
2171                         break;
2172                 case Opt_blank_pass:
2173                         /* passwords have to be handled differently
2174                          * to allow the character used for deliminator
2175                          * to be passed within them
2176                          */
2177
2178                         /*
2179                          * Check if this is a case where the  password
2180                          * starts with a delimiter
2181                          */
2182                         tmp_end = strchr(data, '=');
2183                         tmp_end++;
2184                         if (!(tmp_end < end && tmp_end[1] == delim)) {
2185                                 /* No it is not. Set the password to NULL */
2186                                 kfree_sensitive(vol->password);
2187                                 vol->password = NULL;
2188                                 break;
2189                         }
2190                         fallthrough;    /* to Opt_pass below */
2191                 case Opt_pass:
2192                         /* Obtain the value string */
2193                         value = strchr(data, '=');
2194                         value++;
2195
2196                         /* Set tmp_end to end of the string */
2197                         tmp_end = (char *) value + strlen(value);
2198
2199                         /* Check if following character is the deliminator
2200                          * If yes, we have encountered a double deliminator
2201                          * reset the NULL character to the deliminator
2202                          */
2203                         if (tmp_end < end && tmp_end[1] == delim) {
2204                                 tmp_end[0] = delim;
2205
2206                                 /* Keep iterating until we get to a single
2207                                  * deliminator OR the end
2208                                  */
2209                                 while ((tmp_end = strchr(tmp_end, delim))
2210                                         != NULL && (tmp_end[1] == delim)) {
2211                                                 tmp_end = (char *) &tmp_end[2];
2212                                 }
2213
2214                                 /* Reset var options to point to next element */
2215                                 if (tmp_end) {
2216                                         tmp_end[0] = '\0';
2217                                         options = (char *) &tmp_end[1];
2218                                 } else
2219                                         /* Reached the end of the mount option
2220                                          * string */
2221                                         options = end;
2222                         }
2223
2224                         kfree_sensitive(vol->password);
2225                         /* Now build new password string */
2226                         temp_len = strlen(value);
2227                         vol->password = kzalloc(temp_len+1, GFP_KERNEL);
2228                         if (vol->password == NULL) {
2229                                 pr_warn("no memory for password\n");
2230                                 goto cifs_parse_mount_err;
2231                         }
2232
2233                         for (i = 0, j = 0; i < temp_len; i++, j++) {
2234                                 vol->password[j] = value[i];
2235                                 if ((value[i] == delim) &&
2236                                      value[i+1] == delim)
2237                                         /* skip the second deliminator */
2238                                         i++;
2239                         }
2240                         vol->password[j] = '\0';
2241                         break;
2242                 case Opt_blank_ip:
2243                         /* FIXME: should this be an error instead? */
2244                         got_ip = false;
2245                         break;
2246                 case Opt_ip:
2247                         string = match_strdup(args);
2248                         if (string == NULL)
2249                                 goto out_nomem;
2250
2251                         if (!cifs_convert_address(dstaddr, string,
2252                                         strlen(string))) {
2253                                 pr_err("bad ip= option (%s)\n", string);
2254                                 goto cifs_parse_mount_err;
2255                         }
2256                         got_ip = true;
2257                         break;
2258                 case Opt_domain:
2259                         string = match_strdup(args);
2260                         if (string == NULL)
2261                                 goto out_nomem;
2262
2263                         if (strnlen(string, CIFS_MAX_DOMAINNAME_LEN)
2264                                         == CIFS_MAX_DOMAINNAME_LEN) {
2265                                 pr_warn("domain name too long\n");
2266                                 goto cifs_parse_mount_err;
2267                         }
2268
2269                         kfree(vol->domainname);
2270                         vol->domainname = kstrdup(string, GFP_KERNEL);
2271                         if (!vol->domainname) {
2272                                 pr_warn("no memory for domainname\n");
2273                                 goto cifs_parse_mount_err;
2274                         }
2275                         cifs_dbg(FYI, "Domain name set\n");
2276                         break;
2277                 case Opt_srcaddr:
2278                         string = match_strdup(args);
2279                         if (string == NULL)
2280                                 goto out_nomem;
2281
2282                         if (!cifs_convert_address(
2283                                         (struct sockaddr *)&vol->srcaddr,
2284                                         string, strlen(string))) {
2285                                 pr_warn("Could not parse srcaddr: %s\n",
2286                                         string);
2287                                 goto cifs_parse_mount_err;
2288                         }
2289                         break;
2290                 case Opt_iocharset:
2291                         string = match_strdup(args);
2292                         if (string == NULL)
2293                                 goto out_nomem;
2294
2295                         if (strnlen(string, 1024) >= 65) {
2296                                 pr_warn("iocharset name too long\n");
2297                                 goto cifs_parse_mount_err;
2298                         }
2299
2300                          if (strncasecmp(string, "default", 7) != 0) {
2301                                 kfree(vol->iocharset);
2302                                 vol->iocharset = kstrdup(string,
2303                                                          GFP_KERNEL);
2304                                 if (!vol->iocharset) {
2305                                         pr_warn("no memory for charset\n");
2306                                         goto cifs_parse_mount_err;
2307                                 }
2308                         }
2309                         /* if iocharset not set then load_nls_default
2310                          * is used by caller
2311                          */
2312                          cifs_dbg(FYI, "iocharset set to %s\n", string);
2313                         break;
2314                 case Opt_netbiosname:
2315                         string = match_strdup(args);
2316                         if (string == NULL)
2317                                 goto out_nomem;
2318
2319                         memset(vol->source_rfc1001_name, 0x20,
2320                                 RFC1001_NAME_LEN);
2321                         /*
2322                          * FIXME: are there cases in which a comma can
2323                          * be valid in workstation netbios name (and
2324                          * need special handling)?
2325                          */
2326                         for (i = 0; i < RFC1001_NAME_LEN; i++) {
2327                                 /* don't ucase netbiosname for user */
2328                                 if (string[i] == 0)
2329                                         break;
2330                                 vol->source_rfc1001_name[i] = string[i];
2331                         }
2332                         /* The string has 16th byte zero still from
2333                          * set at top of the function
2334                          */
2335                         if (i == RFC1001_NAME_LEN && string[i] != 0)
2336                                 pr_warn("netbiosname longer than 15 truncated\n");
2337                         break;
2338                 case Opt_servern:
2339                         /* servernetbiosname specified override *SMBSERVER */
2340                         string = match_strdup(args);
2341                         if (string == NULL)
2342                                 goto out_nomem;
2343
2344                         /* last byte, type, is 0x20 for servr type */
2345                         memset(vol->target_rfc1001_name, 0x20,
2346                                 RFC1001_NAME_LEN_WITH_NULL);
2347
2348                         /* BB are there cases in which a comma can be
2349                            valid in this workstation netbios name
2350                            (and need special handling)? */
2351
2352                         /* user or mount helper must uppercase the
2353                            netbios name */
2354                         for (i = 0; i < 15; i++) {
2355                                 if (string[i] == 0)
2356                                         break;
2357                                 vol->target_rfc1001_name[i] = string[i];
2358                         }
2359                         /* The string has 16th byte zero still from
2360                            set at top of the function  */
2361                         if (i == RFC1001_NAME_LEN && string[i] != 0)
2362                                 pr_warn("server netbiosname longer than 15 truncated\n");
2363                         break;
2364                 case Opt_ver:
2365                         /* version of mount userspace tools, not dialect */
2366                         string = match_strdup(args);
2367                         if (string == NULL)
2368                                 goto out_nomem;
2369
2370                         /* If interface changes in mount.cifs bump to new ver */
2371                         if (strncasecmp(string, "1", 1) == 0) {
2372                                 if (strlen(string) > 1) {
2373                                         pr_warn("Bad mount helper ver=%s. Did you want SMB1 (CIFS) dialect and mean to type vers=1.0 instead?\n",
2374                                                 string);
2375                                         goto cifs_parse_mount_err;
2376                                 }
2377                                 /* This is the default */
2378                                 break;
2379                         }
2380                         /* For all other value, error */
2381                         pr_warn("Invalid mount helper version specified\n");
2382                         goto cifs_parse_mount_err;
2383                 case Opt_vers:
2384                         /* protocol version (dialect) */
2385                         string = match_strdup(args);
2386                         if (string == NULL)
2387                                 goto out_nomem;
2388
2389                         if (cifs_parse_smb_version(string, vol, is_smb3) != 0)
2390                                 goto cifs_parse_mount_err;
2391                         got_version = true;
2392                         break;
2393                 case Opt_sec:
2394                         string = match_strdup(args);
2395                         if (string == NULL)
2396                                 goto out_nomem;
2397
2398                         if (cifs_parse_security_flavors(string, vol) != 0)
2399                                 goto cifs_parse_mount_err;
2400                         break;
2401                 case Opt_cache:
2402                         string = match_strdup(args);
2403                         if (string == NULL)
2404                                 goto out_nomem;
2405
2406                         if (cifs_parse_cache_flavor(string, vol) != 0)
2407                                 goto cifs_parse_mount_err;
2408                         break;
2409                 default:
2410                         /*
2411                          * An option we don't recognize. Save it off for later
2412                          * if we haven't already found one
2413                          */
2414                         if (!invalid)
2415                                 invalid = data;
2416                         break;
2417                 }
2418                 /* Free up any allocated string */
2419                 kfree(string);
2420                 string = NULL;
2421         }
2422
2423         if (!sloppy && invalid) {
2424                 pr_err("Unknown mount option \"%s\"\n", invalid);
2425                 goto cifs_parse_mount_err;
2426         }
2427
2428         if (vol->rdma && vol->vals->protocol_id < SMB30_PROT_ID) {
2429                 cifs_dbg(VFS, "SMB Direct requires Version >=3.0\n");
2430                 goto cifs_parse_mount_err;
2431         }
2432
2433 #ifndef CONFIG_KEYS
2434         /* Muliuser mounts require CONFIG_KEYS support */
2435         if (vol->multiuser) {
2436                 cifs_dbg(VFS, "Multiuser mounts require kernels with CONFIG_KEYS enabled\n");
2437                 goto cifs_parse_mount_err;
2438         }
2439 #endif
2440         if (!vol->UNC) {
2441                 cifs_dbg(VFS, "CIFS mount error: No usable UNC path provided in device string!\n");
2442                 goto cifs_parse_mount_err;
2443         }
2444
2445         /* make sure UNC has a share name */
2446         if (!strchr(vol->UNC + 3, '\\')) {
2447                 cifs_dbg(VFS, "Malformed UNC. Unable to find share name.\n");
2448                 goto cifs_parse_mount_err;
2449         }
2450
2451         if (!got_ip) {
2452                 int len;
2453                 const char *slash;
2454
2455                 /* No ip= option specified? Try to get it from UNC */
2456                 /* Use the address part of the UNC. */
2457                 slash = strchr(&vol->UNC[2], '\\');
2458                 len = slash - &vol->UNC[2];
2459                 if (!cifs_convert_address(dstaddr, &vol->UNC[2], len)) {
2460                         pr_err("Unable to determine destination address\n");
2461                         goto cifs_parse_mount_err;
2462                 }
2463         }
2464
2465         /* set the port that we got earlier */
2466         cifs_set_port(dstaddr, port);
2467
2468         if (uid_specified)
2469                 vol->override_uid = override_uid;
2470         else if (override_uid == 1)
2471                 pr_notice("ignoring forceuid mount option specified with no uid= option\n");
2472
2473         if (gid_specified)
2474                 vol->override_gid = override_gid;
2475         else if (override_gid == 1)
2476                 pr_notice("ignoring forcegid mount option specified with no gid= option\n");
2477
2478         if (got_version == false)
2479                 pr_warn_once("No dialect specified on mount. Default has changed to a more secure dialect, SMB2.1 or later (e.g. SMB3.1.1), from CIFS (SMB1). To use the less secure SMB1 dialect to access old servers which do not support SMB3.1.1 (or even SMB3 or SMB2.1) specify vers=1.0 on mount.\n");
2480
2481         kfree(mountdata_copy);
2482         return 0;
2483
2484 out_nomem:
2485         pr_warn("Could not allocate temporary buffer\n");
2486 cifs_parse_mount_err:
2487         kfree(string);
2488         kfree(mountdata_copy);
2489         return 1;
2490 }
2491
2492 /** Returns true if srcaddr isn't specified and rhs isn't
2493  * specified, or if srcaddr is specified and
2494  * matches the IP address of the rhs argument.
2495  */
2496 bool
2497 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
2498 {
2499         switch (srcaddr->sa_family) {
2500         case AF_UNSPEC:
2501                 return (rhs->sa_family == AF_UNSPEC);
2502         case AF_INET: {
2503                 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
2504                 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
2505                 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
2506         }
2507         case AF_INET6: {
2508                 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
2509                 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
2510                 return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
2511         }
2512         default:
2513                 WARN_ON(1);
2514                 return false; /* don't expect to be here */
2515         }
2516 }
2517
2518 /*
2519  * If no port is specified in addr structure, we try to match with 445 port
2520  * and if it fails - with 139 ports. It should be called only if address
2521  * families of server and addr are equal.
2522  */
2523 static bool
2524 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
2525 {
2526         __be16 port, *sport;
2527
2528         /* SMBDirect manages its own ports, don't match it here */
2529         if (server->rdma)
2530                 return true;
2531
2532         switch (addr->sa_family) {
2533         case AF_INET:
2534                 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
2535                 port = ((struct sockaddr_in *) addr)->sin_port;
2536                 break;
2537         case AF_INET6:
2538                 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
2539                 port = ((struct sockaddr_in6 *) addr)->sin6_port;
2540                 break;
2541         default:
2542                 WARN_ON(1);
2543                 return false;
2544         }
2545
2546         if (!port) {
2547                 port = htons(CIFS_PORT);
2548                 if (port == *sport)
2549                         return true;
2550
2551                 port = htons(RFC1001_PORT);
2552         }
2553
2554         return port == *sport;
2555 }
2556
2557 static bool
2558 match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
2559               struct sockaddr *srcaddr)
2560 {
2561         switch (addr->sa_family) {
2562         case AF_INET: {
2563                 struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
2564                 struct sockaddr_in *srv_addr4 =
2565                                         (struct sockaddr_in *)&server->dstaddr;
2566
2567                 if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
2568                         return false;
2569                 break;
2570         }
2571         case AF_INET6: {
2572                 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
2573                 struct sockaddr_in6 *srv_addr6 =
2574                                         (struct sockaddr_in6 *)&server->dstaddr;
2575
2576                 if (!ipv6_addr_equal(&addr6->sin6_addr,
2577                                      &srv_addr6->sin6_addr))
2578                         return false;
2579                 if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
2580                         return false;
2581                 break;
2582         }
2583         default:
2584                 WARN_ON(1);
2585                 return false; /* don't expect to be here */
2586         }
2587
2588         if (!cifs_match_ipaddr(srcaddr, (struct sockaddr *)&server->srcaddr))
2589                 return false;
2590
2591         return true;
2592 }
2593
2594 static bool
2595 match_security(struct TCP_Server_Info *server, struct smb_vol *vol)
2596 {
2597         /*
2598          * The select_sectype function should either return the vol->sectype
2599          * that was specified, or "Unspecified" if that sectype was not
2600          * compatible with the given NEGOTIATE request.
2601          */
2602         if (server->ops->select_sectype(server, vol->sectype)
2603              == Unspecified)
2604                 return false;
2605
2606         /*
2607          * Now check if signing mode is acceptable. No need to check
2608          * global_secflags at this point since if MUST_SIGN is set then
2609          * the server->sign had better be too.
2610          */
2611         if (vol->sign && !server->sign)
2612                 return false;
2613
2614         return true;
2615 }
2616
2617 static int match_server(struct TCP_Server_Info *server, struct smb_vol *vol)
2618 {
2619         struct sockaddr *addr = (struct sockaddr *)&vol->dstaddr;
2620
2621         if (vol->nosharesock)
2622                 return 0;
2623
2624         /* If multidialect negotiation see if existing sessions match one */
2625         if (strcmp(vol->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
2626                 if (server->vals->protocol_id < SMB30_PROT_ID)
2627                         return 0;
2628         } else if (strcmp(vol->vals->version_string,
2629                    SMBDEFAULT_VERSION_STRING) == 0) {
2630                 if (server->vals->protocol_id < SMB21_PROT_ID)
2631                         return 0;
2632         } else if ((server->vals != vol->vals) || (server->ops != vol->ops))
2633                 return 0;
2634
2635         if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
2636                 return 0;
2637
2638         if (!match_address(server, addr,
2639                            (struct sockaddr *)&vol->srcaddr))
2640                 return 0;
2641
2642         if (!match_port(server, addr))
2643                 return 0;
2644
2645         if (!match_security(server, vol))
2646                 return 0;
2647
2648         if (server->echo_interval != vol->echo_interval * HZ)
2649                 return 0;
2650
2651         if (server->rdma != vol->rdma)
2652                 return 0;
2653
2654         if (server->ignore_signature != vol->ignore_signature)
2655                 return 0;
2656
2657         if (server->min_offload != vol->min_offload)
2658                 return 0;
2659
2660         return 1;
2661 }
2662
2663 struct TCP_Server_Info *
2664 cifs_find_tcp_session(struct smb_vol *vol)
2665 {
2666         struct TCP_Server_Info *server;
2667
2668         spin_lock(&cifs_tcp_ses_lock);
2669         list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
2670                 /*
2671                  * Skip ses channels since they're only handled in lower layers
2672                  * (e.g. cifs_send_recv).
2673                  */
2674                 if (server->is_channel || !match_server(server, vol))
2675                         continue;
2676
2677                 ++server->srv_count;
2678                 spin_unlock(&cifs_tcp_ses_lock);
2679                 cifs_dbg(FYI, "Existing tcp session with server found\n");
2680                 return server;
2681         }
2682         spin_unlock(&cifs_tcp_ses_lock);
2683         return NULL;
2684 }
2685
2686 void
2687 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
2688 {
2689         struct task_struct *task;
2690
2691         spin_lock(&cifs_tcp_ses_lock);
2692         if (--server->srv_count > 0) {
2693                 spin_unlock(&cifs_tcp_ses_lock);
2694                 return;
2695         }
2696
2697         put_net(cifs_net_ns(server));
2698
2699         list_del_init(&server->tcp_ses_list);
2700         spin_unlock(&cifs_tcp_ses_lock);
2701
2702         cancel_delayed_work_sync(&server->echo);
2703
2704         if (from_reconnect)
2705                 /*
2706                  * Avoid deadlock here: reconnect work calls
2707                  * cifs_put_tcp_session() at its end. Need to be sure
2708                  * that reconnect work does nothing with server pointer after
2709                  * that step.
2710                  */
2711                 cancel_delayed_work(&server->reconnect);
2712         else
2713                 cancel_delayed_work_sync(&server->reconnect);
2714
2715         spin_lock(&GlobalMid_Lock);
2716         server->tcpStatus = CifsExiting;
2717         spin_unlock(&GlobalMid_Lock);
2718
2719         cifs_crypto_secmech_release(server);
2720         cifs_fscache_release_client_cookie(server);
2721
2722         kfree(server->session_key.response);
2723         server->session_key.response = NULL;
2724         server->session_key.len = 0;
2725
2726         task = xchg(&server->tsk, NULL);
2727         if (task)
2728                 send_sig(SIGKILL, task, 1);
2729 }
2730
2731 struct TCP_Server_Info *
2732 cifs_get_tcp_session(struct smb_vol *volume_info)
2733 {
2734         struct TCP_Server_Info *tcp_ses = NULL;
2735         int rc;
2736
2737         cifs_dbg(FYI, "UNC: %s\n", volume_info->UNC);
2738
2739         /* see if we already have a matching tcp_ses */
2740         tcp_ses = cifs_find_tcp_session(volume_info);
2741         if (tcp_ses)
2742                 return tcp_ses;
2743
2744         tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
2745         if (!tcp_ses) {
2746                 rc = -ENOMEM;
2747                 goto out_err;
2748         }
2749
2750         tcp_ses->ops = volume_info->ops;
2751         tcp_ses->vals = volume_info->vals;
2752         cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
2753         tcp_ses->hostname = extract_hostname(volume_info->UNC);
2754         if (IS_ERR(tcp_ses->hostname)) {
2755                 rc = PTR_ERR(tcp_ses->hostname);
2756                 goto out_err_crypto_release;
2757         }
2758
2759         tcp_ses->noblockcnt = volume_info->rootfs;
2760         tcp_ses->noblocksnd = volume_info->noblocksnd || volume_info->rootfs;
2761         tcp_ses->noautotune = volume_info->noautotune;
2762         tcp_ses->tcp_nodelay = volume_info->sockopt_tcp_nodelay;
2763         tcp_ses->rdma = volume_info->rdma;
2764         tcp_ses->in_flight = 0;
2765         tcp_ses->max_in_flight = 0;
2766         tcp_ses->credits = 1;
2767         init_waitqueue_head(&tcp_ses->response_q);
2768         init_waitqueue_head(&tcp_ses->request_q);
2769         INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
2770         mutex_init(&tcp_ses->srv_mutex);
2771         memcpy(tcp_ses->workstation_RFC1001_name,
2772                 volume_info->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
2773         memcpy(tcp_ses->server_RFC1001_name,
2774                 volume_info->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
2775         tcp_ses->session_estab = false;
2776         tcp_ses->sequence_number = 0;
2777         tcp_ses->reconnect_instance = 1;
2778         tcp_ses->lstrp = jiffies;
2779         tcp_ses->compress_algorithm = cpu_to_le16(volume_info->compression);
2780         spin_lock_init(&tcp_ses->req_lock);
2781         INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
2782         INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
2783         INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
2784         INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
2785         mutex_init(&tcp_ses->reconnect_mutex);
2786         memcpy(&tcp_ses->srcaddr, &volume_info->srcaddr,
2787                sizeof(tcp_ses->srcaddr));
2788         memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
2789                 sizeof(tcp_ses->dstaddr));
2790         if (volume_info->use_client_guid)
2791                 memcpy(tcp_ses->client_guid, volume_info->client_guid,
2792                        SMB2_CLIENT_GUID_SIZE);
2793         else
2794                 generate_random_uuid(tcp_ses->client_guid);
2795         /*
2796          * at this point we are the only ones with the pointer
2797          * to the struct since the kernel thread not created yet
2798          * no need to spinlock this init of tcpStatus or srv_count
2799          */
2800         tcp_ses->tcpStatus = CifsNew;
2801         ++tcp_ses->srv_count;
2802
2803         if (volume_info->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
2804                 volume_info->echo_interval <= SMB_ECHO_INTERVAL_MAX)
2805                 tcp_ses->echo_interval = volume_info->echo_interval * HZ;
2806         else
2807                 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
2808         if (tcp_ses->rdma) {
2809 #ifndef CONFIG_CIFS_SMB_DIRECT
2810                 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
2811                 rc = -ENOENT;
2812                 goto out_err_crypto_release;
2813 #endif
2814                 tcp_ses->smbd_conn = smbd_get_connection(
2815                         tcp_ses, (struct sockaddr *)&volume_info->dstaddr);
2816                 if (tcp_ses->smbd_conn) {
2817                         cifs_dbg(VFS, "RDMA transport established\n");
2818                         rc = 0;
2819                         goto smbd_connected;
2820                 } else {
2821                         rc = -ENOENT;
2822                         goto out_err_crypto_release;
2823                 }
2824         }
2825         rc = ip_connect(tcp_ses);
2826         if (rc < 0) {
2827                 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
2828                 goto out_err_crypto_release;
2829         }
2830 smbd_connected:
2831         /*
2832          * since we're in a cifs function already, we know that
2833          * this will succeed. No need for try_module_get().
2834          */
2835         __module_get(THIS_MODULE);
2836         tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
2837                                   tcp_ses, "cifsd");
2838         if (IS_ERR(tcp_ses->tsk)) {
2839                 rc = PTR_ERR(tcp_ses->tsk);
2840                 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
2841                 module_put(THIS_MODULE);
2842                 goto out_err_crypto_release;
2843         }
2844         tcp_ses->min_offload = volume_info->min_offload;
2845         tcp_ses->tcpStatus = CifsNeedNegotiate;
2846
2847         tcp_ses->nr_targets = 1;
2848         tcp_ses->ignore_signature = volume_info->ignore_signature;
2849         /* thread spawned, put it on the list */
2850         spin_lock(&cifs_tcp_ses_lock);
2851         list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
2852         spin_unlock(&cifs_tcp_ses_lock);
2853
2854         cifs_fscache_get_client_cookie(tcp_ses);
2855
2856         /* queue echo request delayed work */
2857         queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
2858
2859         return tcp_ses;
2860
2861 out_err_crypto_release:
2862         cifs_crypto_secmech_release(tcp_ses);
2863
2864         put_net(cifs_net_ns(tcp_ses));
2865
2866 out_err:
2867         if (tcp_ses) {
2868                 if (!IS_ERR(tcp_ses->hostname))
2869                         kfree(tcp_ses->hostname);
2870                 if (tcp_ses->ssocket)
2871                         sock_release(tcp_ses->ssocket);
2872                 kfree(tcp_ses);
2873         }
2874         return ERR_PTR(rc);
2875 }
2876
2877 static int match_session(struct cifs_ses *ses, struct smb_vol *vol)
2878 {
2879         if (vol->sectype != Unspecified &&
2880             vol->sectype != ses->sectype)
2881                 return 0;
2882
2883         /*
2884          * If an existing session is limited to less channels than
2885          * requested, it should not be reused
2886          */
2887         if (ses->chan_max < vol->max_channels)
2888                 return 0;
2889
2890         switch (ses->sectype) {
2891         case Kerberos:
2892                 if (!uid_eq(vol->cred_uid, ses->cred_uid))
2893                         return 0;
2894                 break;
2895         default:
2896                 /* NULL username means anonymous session */
2897                 if (ses->user_name == NULL) {
2898                         if (!vol->nullauth)
2899                                 return 0;
2900                         break;
2901                 }
2902
2903                 /* anything else takes username/password */
2904                 if (strncmp(ses->user_name,
2905                             vol->username ? vol->username : "",
2906                             CIFS_MAX_USERNAME_LEN))
2907                         return 0;
2908                 if ((vol->username && strlen(vol->username) != 0) &&
2909                     ses->password != NULL &&
2910                     strncmp(ses->password,
2911                             vol->password ? vol->password : "",
2912                             CIFS_MAX_PASSWORD_LEN))
2913                         return 0;
2914         }
2915         return 1;
2916 }
2917
2918 /**
2919  * cifs_setup_ipc - helper to setup the IPC tcon for the session
2920  *
2921  * A new IPC connection is made and stored in the session
2922  * tcon_ipc. The IPC tcon has the same lifetime as the session.
2923  */
2924 static int
2925 cifs_setup_ipc(struct cifs_ses *ses, struct smb_vol *volume_info)
2926 {
2927         int rc = 0, xid;
2928         struct cifs_tcon *tcon;
2929         struct nls_table *nls_codepage;
2930         char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
2931         bool seal = false;
2932         struct TCP_Server_Info *server = ses->server;
2933
2934         /*
2935          * If the mount request that resulted in the creation of the
2936          * session requires encryption, force IPC to be encrypted too.
2937          */
2938         if (volume_info->seal) {
2939                 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
2940                         seal = true;
2941                 else {
2942                         cifs_server_dbg(VFS,
2943                                  "IPC: server doesn't support encryption\n");
2944                         return -EOPNOTSUPP;
2945                 }
2946         }
2947
2948         tcon = tconInfoAlloc();
2949         if (tcon == NULL)
2950                 return -ENOMEM;
2951
2952         scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
2953
2954         /* cannot fail */
2955         nls_codepage = load_nls_default();
2956
2957         xid = get_xid();
2958         tcon->ses = ses;
2959         tcon->ipc = true;
2960         tcon->seal = seal;
2961         rc = server->ops->tree_connect(xid, ses, unc, tcon, nls_codepage);
2962         free_xid(xid);
2963
2964         if (rc) {
2965                 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
2966                 tconInfoFree(tcon);
2967                 goto out;
2968         }
2969
2970         cifs_dbg(FYI, "IPC tcon rc = %d ipc tid = %d\n", rc, tcon->tid);
2971
2972         ses->tcon_ipc = tcon;
2973 out:
2974         unload_nls(nls_codepage);
2975         return rc;
2976 }
2977
2978 /**
2979  * cifs_free_ipc - helper to release the session IPC tcon
2980  *
2981  * Needs to be called everytime a session is destroyed
2982  */
2983 static int
2984 cifs_free_ipc(struct cifs_ses *ses)
2985 {
2986         int rc = 0, xid;
2987         struct cifs_tcon *tcon = ses->tcon_ipc;
2988
2989         if (tcon == NULL)
2990                 return 0;
2991
2992         if (ses->server->ops->tree_disconnect) {
2993                 xid = get_xid();
2994                 rc = ses->server->ops->tree_disconnect(xid, tcon);
2995                 free_xid(xid);
2996         }
2997
2998         if (rc)
2999                 cifs_dbg(FYI, "failed to disconnect IPC tcon (rc=%d)\n", rc);
3000
3001         tconInfoFree(tcon);
3002         ses->tcon_ipc = NULL;
3003         return rc;
3004 }
3005
3006 static struct cifs_ses *
3007 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb_vol *vol)
3008 {
3009         struct cifs_ses *ses;
3010
3011         spin_lock(&cifs_tcp_ses_lock);
3012         list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
3013                 if (ses->status == CifsExiting)
3014                         continue;
3015                 if (!match_session(ses, vol))
3016                         continue;
3017                 ++ses->ses_count;
3018                 spin_unlock(&cifs_tcp_ses_lock);
3019                 return ses;
3020         }
3021         spin_unlock(&cifs_tcp_ses_lock);
3022         return NULL;
3023 }
3024
3025 void cifs_put_smb_ses(struct cifs_ses *ses)
3026 {
3027         unsigned int rc, xid;
3028         struct TCP_Server_Info *server = ses->server;
3029
3030         cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
3031
3032         spin_lock(&cifs_tcp_ses_lock);
3033         if (ses->status == CifsExiting) {
3034                 spin_unlock(&cifs_tcp_ses_lock);
3035                 return;
3036         }
3037         if (--ses->ses_count > 0) {
3038                 spin_unlock(&cifs_tcp_ses_lock);
3039                 return;
3040         }
3041         if (ses->status == CifsGood)
3042                 ses->status = CifsExiting;
3043         spin_unlock(&cifs_tcp_ses_lock);
3044
3045         cifs_free_ipc(ses);
3046
3047         if (ses->status == CifsExiting && server->ops->logoff) {
3048                 xid = get_xid();
3049                 rc = server->ops->logoff(xid, ses);
3050                 if (rc)
3051                         cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
3052                                 __func__, rc);
3053                 _free_xid(xid);
3054         }
3055
3056         spin_lock(&cifs_tcp_ses_lock);
3057         list_del_init(&ses->smb_ses_list);
3058         spin_unlock(&cifs_tcp_ses_lock);
3059
3060         /* close any extra channels */
3061         if (ses->chan_count > 1) {
3062                 int i;
3063
3064                 for (i = 1; i < ses->chan_count; i++)
3065                         cifs_put_tcp_session(ses->chans[i].server, 0);
3066         }
3067
3068         sesInfoFree(ses);
3069         cifs_put_tcp_session(server, 0);
3070 }
3071
3072 #ifdef CONFIG_KEYS
3073
3074 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
3075 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
3076
3077 /* Populate username and pw fields from keyring if possible */
3078 static int
3079 cifs_set_cifscreds(struct smb_vol *vol, struct cifs_ses *ses)
3080 {
3081         int rc = 0;
3082         int is_domain = 0;
3083         const char *delim, *payload;
3084         char *desc;
3085         ssize_t len;
3086         struct key *key;
3087         struct TCP_Server_Info *server = ses->server;
3088         struct sockaddr_in *sa;
3089         struct sockaddr_in6 *sa6;
3090         const struct user_key_payload *upayload;
3091
3092         desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
3093         if (!desc)
3094                 return -ENOMEM;
3095
3096         /* try to find an address key first */
3097         switch (server->dstaddr.ss_family) {
3098         case AF_INET:
3099                 sa = (struct sockaddr_in *)&server->dstaddr;
3100                 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
3101                 break;
3102         case AF_INET6:
3103                 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
3104                 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
3105                 break;
3106         default:
3107                 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
3108                          server->dstaddr.ss_family);
3109                 rc = -EINVAL;
3110                 goto out_err;
3111         }
3112
3113         cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
3114         key = request_key(&key_type_logon, desc, "");
3115         if (IS_ERR(key)) {
3116                 if (!ses->domainName) {
3117                         cifs_dbg(FYI, "domainName is NULL\n");
3118                         rc = PTR_ERR(key);
3119                         goto out_err;
3120                 }
3121
3122                 /* didn't work, try to find a domain key */
3123                 sprintf(desc, "cifs:d:%s", ses->domainName);
3124                 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
3125                 key = request_key(&key_type_logon, desc, "");
3126                 if (IS_ERR(key)) {
3127                         rc = PTR_ERR(key);
3128                         goto out_err;
3129                 }
3130                 is_domain = 1;
3131         }
3132
3133         down_read(&key->sem);
3134         upayload = user_key_payload_locked(key);
3135         if (IS_ERR_OR_NULL(upayload)) {
3136                 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
3137                 goto out_key_put;
3138         }
3139
3140         /* find first : in payload */
3141         payload = upayload->data;
3142         delim = strnchr(payload, upayload->datalen, ':');
3143         cifs_dbg(FYI, "payload=%s\n", payload);
3144         if (!delim) {
3145                 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
3146                          upayload->datalen);
3147                 rc = -EINVAL;
3148                 goto out_key_put;
3149         }
3150
3151         len = delim - payload;
3152         if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
3153                 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
3154                          len);
3155                 rc = -EINVAL;
3156                 goto out_key_put;
3157         }
3158
3159         vol->username = kstrndup(payload, len, GFP_KERNEL);
3160         if (!vol->username) {
3161                 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
3162                          len);
3163                 rc = -ENOMEM;
3164                 goto out_key_put;
3165         }
3166         cifs_dbg(FYI, "%s: username=%s\n", __func__, vol->username);
3167
3168         len = key->datalen - (len + 1);
3169         if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
3170                 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
3171                 rc = -EINVAL;
3172                 kfree(vol->username);
3173                 vol->username = NULL;
3174                 goto out_key_put;
3175         }
3176
3177         ++delim;
3178         vol->password = kstrndup(delim, len, GFP_KERNEL);
3179         if (!vol->password) {
3180                 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
3181                          len);
3182                 rc = -ENOMEM;
3183                 kfree(vol->username);
3184                 vol->username = NULL;
3185                 goto out_key_put;
3186         }
3187
3188         /*
3189          * If we have a domain key then we must set the domainName in the
3190          * for the request.
3191          */
3192         if (is_domain && ses->domainName) {
3193                 vol->domainname = kstrndup(ses->domainName,
3194                                            strlen(ses->domainName),
3195                                            GFP_KERNEL);
3196                 if (!vol->domainname) {
3197                         cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
3198                                  len);
3199                         rc = -ENOMEM;
3200                         kfree(vol->username);
3201                         vol->username = NULL;
3202                         kfree_sensitive(vol->password);
3203                         vol->password = NULL;
3204                         goto out_key_put;
3205                 }
3206         }
3207
3208 out_key_put:
3209         up_read(&key->sem);
3210         key_put(key);
3211 out_err:
3212         kfree(desc);
3213         cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
3214         return rc;
3215 }
3216 #else /* ! CONFIG_KEYS */
3217 static inline int
3218 cifs_set_cifscreds(struct smb_vol *vol __attribute__((unused)),
3219                    struct cifs_ses *ses __attribute__((unused)))
3220 {
3221         return -ENOSYS;
3222 }
3223 #endif /* CONFIG_KEYS */
3224
3225 /**
3226  * cifs_get_smb_ses - get a session matching @volume_info data from @server
3227  *
3228  * This function assumes it is being called from cifs_mount() where we
3229  * already got a server reference (server refcount +1). See
3230  * cifs_get_tcon() for refcount explanations.
3231  */
3232 struct cifs_ses *
3233 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
3234 {
3235         int rc = -ENOMEM;
3236         unsigned int xid;
3237         struct cifs_ses *ses;
3238         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3239         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3240
3241         xid = get_xid();
3242
3243         ses = cifs_find_smb_ses(server, volume_info);
3244         if (ses) {
3245                 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
3246                          ses->status);
3247
3248                 mutex_lock(&ses->session_mutex);
3249                 rc = cifs_negotiate_protocol(xid, ses);
3250                 if (rc) {
3251                         mutex_unlock(&ses->session_mutex);
3252                         /* problem -- put our ses reference */
3253                         cifs_put_smb_ses(ses);
3254                         free_xid(xid);
3255                         return ERR_PTR(rc);
3256                 }
3257                 if (ses->need_reconnect) {
3258                         cifs_dbg(FYI, "Session needs reconnect\n");
3259                         rc = cifs_setup_session(xid, ses,
3260                                                 volume_info->local_nls);
3261                         if (rc) {
3262                                 mutex_unlock(&ses->session_mutex);
3263                                 /* problem -- put our reference */
3264                                 cifs_put_smb_ses(ses);
3265                                 free_xid(xid);
3266                                 return ERR_PTR(rc);
3267                         }
3268                 }
3269                 mutex_unlock(&ses->session_mutex);
3270
3271                 /* existing SMB ses has a server reference already */
3272                 cifs_put_tcp_session(server, 0);
3273                 free_xid(xid);
3274                 return ses;
3275         }
3276
3277         cifs_dbg(FYI, "Existing smb sess not found\n");
3278         ses = sesInfoAlloc();
3279         if (ses == NULL)
3280                 goto get_ses_fail;
3281
3282         /* new SMB session uses our server ref */
3283         ses->server = server;
3284         if (server->dstaddr.ss_family == AF_INET6)
3285                 sprintf(ses->serverName, "%pI6", &addr6->sin6_addr);
3286         else
3287                 sprintf(ses->serverName, "%pI4", &addr->sin_addr);
3288
3289         if (volume_info->username) {
3290                 ses->user_name = kstrdup(volume_info->username, GFP_KERNEL);
3291                 if (!ses->user_name)
3292                         goto get_ses_fail;
3293         }
3294
3295         /* volume_info->password freed at unmount */
3296         if (volume_info->password) {
3297                 ses->password = kstrdup(volume_info->password, GFP_KERNEL);
3298                 if (!ses->password)
3299                         goto get_ses_fail;
3300         }
3301         if (volume_info->domainname) {
3302                 ses->domainName = kstrdup(volume_info->domainname, GFP_KERNEL);
3303                 if (!ses->domainName)
3304                         goto get_ses_fail;
3305         }
3306         if (volume_info->domainauto)
3307                 ses->domainAuto = volume_info->domainauto;
3308         ses->cred_uid = volume_info->cred_uid;
3309         ses->linux_uid = volume_info->linux_uid;
3310
3311         ses->sectype = volume_info->sectype;
3312         ses->sign = volume_info->sign;
3313         mutex_lock(&ses->session_mutex);
3314
3315         /* add server as first channel */
3316         ses->chans[0].server = server;
3317         ses->chan_count = 1;
3318         ses->chan_max = volume_info->multichannel ? volume_info->max_channels:1;
3319
3320         rc = cifs_negotiate_protocol(xid, ses);
3321         if (!rc)
3322                 rc = cifs_setup_session(xid, ses, volume_info->local_nls);
3323
3324         /* each channel uses a different signing key */
3325         memcpy(ses->chans[0].signkey, ses->smb3signingkey,
3326                sizeof(ses->smb3signingkey));
3327
3328         mutex_unlock(&ses->session_mutex);
3329         if (rc)
3330                 goto get_ses_fail;
3331
3332         /* success, put it on the list and add it as first channel */
3333         spin_lock(&cifs_tcp_ses_lock);
3334         list_add(&ses->smb_ses_list, &server->smb_ses_list);
3335         spin_unlock(&cifs_tcp_ses_lock);
3336
3337         free_xid(xid);
3338
3339         cifs_setup_ipc(ses, volume_info);
3340
3341         return ses;
3342
3343 get_ses_fail:
3344         sesInfoFree(ses);
3345         free_xid(xid);
3346         return ERR_PTR(rc);
3347 }
3348
3349 static int match_tcon(struct cifs_tcon *tcon, struct smb_vol *volume_info)
3350 {
3351         if (tcon->tidStatus == CifsExiting)
3352                 return 0;
3353         if (strncmp(tcon->treeName, volume_info->UNC, MAX_TREE_SIZE))
3354                 return 0;
3355         if (tcon->seal != volume_info->seal)
3356                 return 0;
3357         if (tcon->snapshot_time != volume_info->snapshot_time)
3358                 return 0;
3359         if (tcon->handle_timeout != volume_info->handle_timeout)
3360                 return 0;
3361         if (tcon->no_lease != volume_info->no_lease)
3362                 return 0;
3363         if (tcon->nodelete != volume_info->nodelete)
3364                 return 0;
3365         return 1;
3366 }
3367
3368 static struct cifs_tcon *
3369 cifs_find_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
3370 {
3371         struct list_head *tmp;
3372         struct cifs_tcon *tcon;
3373
3374         spin_lock(&cifs_tcp_ses_lock);
3375         list_for_each(tmp, &ses->tcon_list) {
3376                 tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
3377 #ifdef CONFIG_CIFS_DFS_UPCALL
3378                 if (tcon->dfs_path)
3379                         continue;
3380 #endif
3381                 if (!match_tcon(tcon, volume_info))
3382                         continue;
3383                 ++tcon->tc_count;
3384                 spin_unlock(&cifs_tcp_ses_lock);
3385                 return tcon;
3386         }
3387         spin_unlock(&cifs_tcp_ses_lock);
3388         return NULL;
3389 }
3390
3391 void
3392 cifs_put_tcon(struct cifs_tcon *tcon)
3393 {
3394         unsigned int xid;
3395         struct cifs_ses *ses;
3396
3397         /*
3398          * IPC tcon share the lifetime of their session and are
3399          * destroyed in the session put function
3400          */
3401         if (tcon == NULL || tcon->ipc)
3402                 return;
3403
3404         ses = tcon->ses;
3405         cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
3406         spin_lock(&cifs_tcp_ses_lock);
3407         if (--tcon->tc_count > 0) {
3408                 spin_unlock(&cifs_tcp_ses_lock);
3409                 return;
3410         }
3411
3412         list_del_init(&tcon->tcon_list);
3413         spin_unlock(&cifs_tcp_ses_lock);
3414
3415         xid = get_xid();
3416         if (ses->server->ops->tree_disconnect)
3417                 ses->server->ops->tree_disconnect(xid, tcon);
3418         _free_xid(xid);
3419
3420         cifs_fscache_release_super_cookie(tcon);
3421         tconInfoFree(tcon);
3422         cifs_put_smb_ses(ses);
3423 }
3424
3425 /**
3426  * cifs_get_tcon - get a tcon matching @volume_info data from @ses
3427  *
3428  * - tcon refcount is the number of mount points using the tcon.
3429  * - ses refcount is the number of tcon using the session.
3430  *
3431  * 1. This function assumes it is being called from cifs_mount() where
3432  *    we already got a session reference (ses refcount +1).
3433  *
3434  * 2. Since we're in the context of adding a mount point, the end
3435  *    result should be either:
3436  *
3437  * a) a new tcon already allocated with refcount=1 (1 mount point) and
3438  *    its session refcount incremented (1 new tcon). This +1 was
3439  *    already done in (1).
3440  *
3441  * b) an existing tcon with refcount+1 (add a mount point to it) and
3442  *    identical ses refcount (no new tcon). Because of (1) we need to
3443  *    decrement the ses refcount.
3444  */
3445 static struct cifs_tcon *
3446 cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
3447 {
3448         int rc, xid;
3449         struct cifs_tcon *tcon;
3450
3451         tcon = cifs_find_tcon(ses, volume_info);
3452         if (tcon) {
3453                 /*
3454                  * tcon has refcount already incremented but we need to
3455                  * decrement extra ses reference gotten by caller (case b)
3456                  */
3457                 cifs_dbg(FYI, "Found match on UNC path\n");
3458                 cifs_put_smb_ses(ses);
3459                 return tcon;
3460         }
3461
3462         if (!ses->server->ops->tree_connect) {
3463                 rc = -ENOSYS;
3464                 goto out_fail;
3465         }
3466
3467         tcon = tconInfoAlloc();
3468         if (tcon == NULL) {
3469                 rc = -ENOMEM;
3470                 goto out_fail;
3471         }
3472
3473         if (volume_info->snapshot_time) {
3474                 if (ses->server->vals->protocol_id == 0) {
3475                         cifs_dbg(VFS,
3476                              "Use SMB2 or later for snapshot mount option\n");
3477                         rc = -EOPNOTSUPP;
3478                         goto out_fail;
3479                 } else
3480                         tcon->snapshot_time = volume_info->snapshot_time;
3481         }
3482
3483         if (volume_info->handle_timeout) {
3484                 if (ses->server->vals->protocol_id == 0) {
3485                         cifs_dbg(VFS,
3486                              "Use SMB2.1 or later for handle timeout option\n");
3487                         rc = -EOPNOTSUPP;
3488                         goto out_fail;
3489                 } else
3490                         tcon->handle_timeout = volume_info->handle_timeout;
3491         }
3492
3493         tcon->ses = ses;
3494         if (volume_info->password) {
3495                 tcon->password = kstrdup(volume_info->password, GFP_KERNEL);
3496                 if (!tcon->password) {
3497                         rc = -ENOMEM;
3498                         goto out_fail;
3499                 }
3500         }
3501
3502         if (volume_info->seal) {
3503                 if (ses->server->vals->protocol_id == 0) {
3504                         cifs_dbg(VFS,
3505                                  "SMB3 or later required for encryption\n");
3506                         rc = -EOPNOTSUPP;
3507                         goto out_fail;
3508                 } else if (tcon->ses->server->capabilities &
3509                                         SMB2_GLOBAL_CAP_ENCRYPTION)
3510                         tcon->seal = true;
3511                 else {
3512                         cifs_dbg(VFS, "Encryption is not supported on share\n");
3513                         rc = -EOPNOTSUPP;
3514                         goto out_fail;
3515                 }
3516         }
3517
3518         if (volume_info->linux_ext) {
3519                 if (ses->server->posix_ext_supported) {
3520                         tcon->posix_extensions = true;
3521                         pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
3522                 } else {
3523                         cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
3524                         rc = -EOPNOTSUPP;
3525                         goto out_fail;
3526                 }
3527         }
3528
3529         /*
3530          * BB Do we need to wrap session_mutex around this TCon call and Unix
3531          * SetFS as we do on SessSetup and reconnect?
3532          */
3533         xid = get_xid();
3534         rc = ses->server->ops->tree_connect(xid, ses, volume_info->UNC, tcon,
3535                                             volume_info->local_nls);
3536         free_xid(xid);
3537         cifs_dbg(FYI, "Tcon rc = %d\n", rc);
3538         if (rc)
3539                 goto out_fail;
3540
3541         tcon->use_persistent = false;
3542         /* check if SMB2 or later, CIFS does not support persistent handles */
3543         if (volume_info->persistent) {
3544                 if (ses->server->vals->protocol_id == 0) {
3545                         cifs_dbg(VFS,
3546                              "SMB3 or later required for persistent handles\n");
3547                         rc = -EOPNOTSUPP;
3548                         goto out_fail;
3549                 } else if (ses->server->capabilities &
3550                            SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
3551                         tcon->use_persistent = true;
3552                 else /* persistent handles requested but not supported */ {
3553                         cifs_dbg(VFS,
3554                                 "Persistent handles not supported on share\n");
3555                         rc = -EOPNOTSUPP;
3556                         goto out_fail;
3557                 }
3558         } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
3559              && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
3560              && (volume_info->nopersistent == false)) {
3561                 cifs_dbg(FYI, "enabling persistent handles\n");
3562                 tcon->use_persistent = true;
3563         } else if (volume_info->resilient) {
3564                 if (ses->server->vals->protocol_id == 0) {
3565                         cifs_dbg(VFS,
3566                              "SMB2.1 or later required for resilient handles\n");
3567                         rc = -EOPNOTSUPP;
3568                         goto out_fail;
3569                 }
3570                 tcon->use_resilient = true;
3571         }
3572
3573         /* If the user really knows what they are doing they can override */
3574         if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
3575                 if (volume_info->cache_ro)
3576                         cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
3577                 else if (volume_info->cache_rw)
3578                         cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
3579         }
3580
3581         if (volume_info->no_lease) {
3582                 if (ses->server->vals->protocol_id == 0) {
3583                         cifs_dbg(VFS,
3584                                 "SMB2 or later required for nolease option\n");
3585                         rc = -EOPNOTSUPP;
3586                         goto out_fail;
3587                 } else
3588                         tcon->no_lease = volume_info->no_lease;
3589         }
3590
3591         /*
3592          * We can have only one retry value for a connection to a share so for
3593          * resources mounted more than once to the same server share the last
3594          * value passed in for the retry flag is used.
3595          */
3596         tcon->retry = volume_info->retry;
3597         tcon->nocase = volume_info->nocase;
3598         tcon->nohandlecache = volume_info->nohandlecache;
3599         tcon->nodelete = volume_info->nodelete;
3600         tcon->local_lease = volume_info->local_lease;
3601         INIT_LIST_HEAD(&tcon->pending_opens);
3602
3603         spin_lock(&cifs_tcp_ses_lock);
3604         list_add(&tcon->tcon_list, &ses->tcon_list);
3605         spin_unlock(&cifs_tcp_ses_lock);
3606
3607         cifs_fscache_get_super_cookie(tcon);
3608
3609         return tcon;
3610
3611 out_fail:
3612         tconInfoFree(tcon);
3613         return ERR_PTR(rc);
3614 }
3615
3616 void
3617 cifs_put_tlink(struct tcon_link *tlink)
3618 {
3619         if (!tlink || IS_ERR(tlink))
3620                 return;
3621
3622         if (!atomic_dec_and_test(&tlink->tl_count) ||
3623             test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
3624                 tlink->tl_time = jiffies;
3625                 return;
3626         }
3627
3628         if (!IS_ERR(tlink_tcon(tlink)))
3629                 cifs_put_tcon(tlink_tcon(tlink));
3630         kfree(tlink);
3631         return;
3632 }
3633
3634 static int
3635 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
3636 {
3637         struct cifs_sb_info *old = CIFS_SB(sb);
3638         struct cifs_sb_info *new = mnt_data->cifs_sb;
3639         unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
3640         unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
3641
3642         if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
3643                 return 0;
3644
3645         if (old->mnt_cifs_serverino_autodisabled)
3646                 newflags &= ~CIFS_MOUNT_SERVER_INUM;
3647
3648         if (oldflags != newflags)
3649                 return 0;
3650
3651         /*
3652          * We want to share sb only if we don't specify an r/wsize or
3653          * specified r/wsize is greater than or equal to existing one.
3654          */
3655         if (new->wsize && new->wsize < old->wsize)
3656                 return 0;
3657
3658         if (new->rsize && new->rsize < old->rsize)
3659                 return 0;
3660
3661         if (!uid_eq(old->mnt_uid, new->mnt_uid) || !gid_eq(old->mnt_gid, new->mnt_gid))
3662                 return 0;
3663
3664         if (old->mnt_file_mode != new->mnt_file_mode ||
3665             old->mnt_dir_mode != new->mnt_dir_mode)
3666                 return 0;
3667
3668         if (strcmp(old->local_nls->charset, new->local_nls->charset))
3669                 return 0;
3670
3671         if (old->actimeo != new->actimeo)
3672                 return 0;
3673
3674         return 1;
3675 }
3676
3677 static int
3678 match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
3679 {
3680         struct cifs_sb_info *old = CIFS_SB(sb);
3681         struct cifs_sb_info *new = mnt_data->cifs_sb;
3682         bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
3683                 old->prepath;
3684         bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
3685                 new->prepath;
3686
3687         if (old_set && new_set && !strcmp(new->prepath, old->prepath))
3688                 return 1;
3689         else if (!old_set && !new_set)
3690                 return 1;
3691
3692         return 0;
3693 }
3694
3695 int
3696 cifs_match_super(struct super_block *sb, void *data)
3697 {
3698         struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data;
3699         struct smb_vol *volume_info;
3700         struct cifs_sb_info *cifs_sb;
3701         struct TCP_Server_Info *tcp_srv;
3702         struct cifs_ses *ses;
3703         struct cifs_tcon *tcon;
3704         struct tcon_link *tlink;
3705         int rc = 0;
3706
3707         spin_lock(&cifs_tcp_ses_lock);
3708         cifs_sb = CIFS_SB(sb);
3709         tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
3710         if (IS_ERR(tlink)) {
3711                 spin_unlock(&cifs_tcp_ses_lock);
3712                 return rc;
3713         }
3714         tcon = tlink_tcon(tlink);
3715         ses = tcon->ses;
3716         tcp_srv = ses->server;
3717
3718         volume_info = mnt_data->vol;
3719
3720         if (!match_server(tcp_srv, volume_info) ||
3721             !match_session(ses, volume_info) ||
3722             !match_tcon(tcon, volume_info) ||
3723             !match_prepath(sb, mnt_data)) {
3724                 rc = 0;
3725                 goto out;
3726         }
3727
3728         rc = compare_mount_options(sb, mnt_data);
3729 out:
3730         spin_unlock(&cifs_tcp_ses_lock);
3731         cifs_put_tlink(tlink);
3732         return rc;
3733 }
3734
3735 #ifdef CONFIG_DEBUG_LOCK_ALLOC
3736 static struct lock_class_key cifs_key[2];
3737 static struct lock_class_key cifs_slock_key[2];
3738
3739 static inline void
3740 cifs_reclassify_socket4(struct socket *sock)
3741 {
3742         struct sock *sk = sock->sk;
3743         BUG_ON(!sock_allow_reclassification(sk));
3744         sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
3745                 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
3746 }
3747
3748 static inline void
3749 cifs_reclassify_socket6(struct socket *sock)
3750 {
3751         struct sock *sk = sock->sk;
3752         BUG_ON(!sock_allow_reclassification(sk));
3753         sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
3754                 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
3755 }
3756 #else
3757 static inline void
3758 cifs_reclassify_socket4(struct socket *sock)
3759 {
3760 }
3761
3762 static inline void
3763 cifs_reclassify_socket6(struct socket *sock)
3764 {
3765 }
3766 #endif
3767
3768 /* See RFC1001 section 14 on representation of Netbios names */
3769 static void rfc1002mangle(char *target, char *source, unsigned int length)
3770 {
3771         unsigned int i, j;
3772
3773         for (i = 0, j = 0; i < (length); i++) {
3774                 /* mask a nibble at a time and encode */
3775                 target[j] = 'A' + (0x0F & (source[i] >> 4));
3776                 target[j+1] = 'A' + (0x0F & source[i]);
3777                 j += 2;
3778         }
3779
3780 }
3781
3782 static int
3783 bind_socket(struct TCP_Server_Info *server)
3784 {
3785         int rc = 0;
3786         if (server->srcaddr.ss_family != AF_UNSPEC) {
3787                 /* Bind to the specified local IP address */
3788                 struct socket *socket = server->ssocket;
3789                 rc = socket->ops->bind(socket,
3790                                        (struct sockaddr *) &server->srcaddr,
3791                                        sizeof(server->srcaddr));
3792                 if (rc < 0) {
3793                         struct sockaddr_in *saddr4;
3794                         struct sockaddr_in6 *saddr6;
3795                         saddr4 = (struct sockaddr_in *)&server->srcaddr;
3796                         saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
3797                         if (saddr6->sin6_family == AF_INET6)
3798                                 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
3799                                          &saddr6->sin6_addr, rc);
3800                         else
3801                                 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
3802                                          &saddr4->sin_addr.s_addr, rc);
3803                 }
3804         }
3805         return rc;
3806 }
3807
3808 static int
3809 ip_rfc1001_connect(struct TCP_Server_Info *server)
3810 {
3811         int rc = 0;
3812         /*
3813          * some servers require RFC1001 sessinit before sending
3814          * negprot - BB check reconnection in case where second
3815          * sessinit is sent but no second negprot
3816          */
3817         struct rfc1002_session_packet *ses_init_buf;
3818         struct smb_hdr *smb_buf;
3819         ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
3820                                GFP_KERNEL);
3821         if (ses_init_buf) {
3822                 ses_init_buf->trailer.session_req.called_len = 32;
3823
3824                 if (server->server_RFC1001_name[0] != 0)
3825                         rfc1002mangle(ses_init_buf->trailer.
3826                                       session_req.called_name,
3827                                       server->server_RFC1001_name,
3828                                       RFC1001_NAME_LEN_WITH_NULL);
3829                 else
3830                         rfc1002mangle(ses_init_buf->trailer.
3831                                       session_req.called_name,
3832                                       DEFAULT_CIFS_CALLED_NAME,
3833                                       RFC1001_NAME_LEN_WITH_NULL);
3834
3835                 ses_init_buf->trailer.session_req.calling_len = 32;
3836
3837                 /*
3838                  * calling name ends in null (byte 16) from old smb
3839                  * convention.
3840                  */
3841                 if (server->workstation_RFC1001_name[0] != 0)
3842                         rfc1002mangle(ses_init_buf->trailer.
3843                                       session_req.calling_name,
3844                                       server->workstation_RFC1001_name,
3845                                       RFC1001_NAME_LEN_WITH_NULL);
3846                 else
3847                         rfc1002mangle(ses_init_buf->trailer.
3848                                       session_req.calling_name,
3849                                       "LINUX_CIFS_CLNT",
3850                                       RFC1001_NAME_LEN_WITH_NULL);
3851
3852                 ses_init_buf->trailer.session_req.scope1 = 0;
3853                 ses_init_buf->trailer.session_req.scope2 = 0;
3854                 smb_buf = (struct smb_hdr *)ses_init_buf;
3855
3856                 /* sizeof RFC1002_SESSION_REQUEST with no scope */
3857                 smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
3858                 rc = smb_send(server, smb_buf, 0x44);
3859                 kfree(ses_init_buf);
3860                 /*
3861                  * RFC1001 layer in at least one server
3862                  * requires very short break before negprot
3863                  * presumably because not expecting negprot
3864                  * to follow so fast.  This is a simple
3865                  * solution that works without
3866                  * complicating the code and causes no
3867                  * significant slowing down on mount
3868                  * for everyone else
3869                  */
3870                 usleep_range(1000, 2000);
3871         }
3872         /*
3873          * else the negprot may still work without this
3874          * even though malloc failed
3875          */
3876
3877         return rc;
3878 }
3879
3880 static int
3881 generic_ip_connect(struct TCP_Server_Info *server)
3882 {
3883         int rc = 0;
3884         __be16 sport;
3885         int slen, sfamily;
3886         struct socket *socket = server->ssocket;
3887         struct sockaddr *saddr;
3888
3889         saddr = (struct sockaddr *) &server->dstaddr;
3890
3891         if (server->dstaddr.ss_family == AF_INET6) {
3892                 sport = ((struct sockaddr_in6 *) saddr)->sin6_port;
3893                 slen = sizeof(struct sockaddr_in6);
3894                 sfamily = AF_INET6;
3895         } else {
3896                 sport = ((struct sockaddr_in *) saddr)->sin_port;
3897                 slen = sizeof(struct sockaddr_in);
3898                 sfamily = AF_INET;
3899         }
3900
3901         if (socket == NULL) {
3902                 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
3903                                    IPPROTO_TCP, &socket, 1);
3904                 if (rc < 0) {
3905                         cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
3906                         server->ssocket = NULL;
3907                         return rc;
3908                 }
3909
3910                 /* BB other socket options to set KEEPALIVE, NODELAY? */
3911                 cifs_dbg(FYI, "Socket created\n");
3912                 server->ssocket = socket;
3913                 socket->sk->sk_allocation = GFP_NOFS;
3914                 if (sfamily == AF_INET6)
3915                         cifs_reclassify_socket6(socket);
3916                 else
3917                         cifs_reclassify_socket4(socket);
3918         }
3919
3920         rc = bind_socket(server);
3921         if (rc < 0)
3922                 return rc;
3923
3924         /*
3925          * Eventually check for other socket options to change from
3926          * the default. sock_setsockopt not used because it expects
3927          * user space buffer
3928          */
3929         socket->sk->sk_rcvtimeo = 7 * HZ;
3930         socket->sk->sk_sndtimeo = 5 * HZ;
3931
3932         /* make the bufsizes depend on wsize/rsize and max requests */
3933         if (server->noautotune) {
3934                 if (socket->sk->sk_sndbuf < (200 * 1024))
3935                         socket->sk->sk_sndbuf = 200 * 1024;
3936                 if (socket->sk->sk_rcvbuf < (140 * 1024))
3937                         socket->sk->sk_rcvbuf = 140 * 1024;
3938         }
3939
3940         if (server->tcp_nodelay)
3941                 tcp_sock_set_nodelay(socket->sk);
3942
3943         cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
3944                  socket->sk->sk_sndbuf,
3945                  socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
3946
3947         rc = socket->ops->connect(socket, saddr, slen,
3948                                   server->noblockcnt ? O_NONBLOCK : 0);
3949         /*
3950          * When mounting SMB root file systems, we do not want to block in
3951          * connect. Otherwise bail out and then let cifs_reconnect() perform
3952          * reconnect failover - if possible.
3953          */
3954         if (server->noblockcnt && rc == -EINPROGRESS)
3955                 rc = 0;
3956         if (rc < 0) {
3957                 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3958                 sock_release(socket);
3959                 server->ssocket = NULL;
3960                 return rc;
3961         }
3962
3963         if (sport == htons(RFC1001_PORT))
3964                 rc = ip_rfc1001_connect(server);
3965
3966         return rc;
3967 }
3968
3969 static int
3970 ip_connect(struct TCP_Server_Info *server)
3971 {
3972         __be16 *sport;
3973         struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3974         struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3975
3976         if (server->dstaddr.ss_family == AF_INET6)
3977                 sport = &addr6->sin6_port;
3978         else
3979                 sport = &addr->sin_port;
3980
3981         if (*sport == 0) {
3982                 int rc;
3983
3984                 /* try with 445 port at first */
3985                 *sport = htons(CIFS_PORT);
3986
3987                 rc = generic_ip_connect(server);
3988                 if (rc >= 0)
3989                         return rc;
3990
3991                 /* if it failed, try with 139 port */
3992                 *sport = htons(RFC1001_PORT);
3993         }
3994
3995         return generic_ip_connect(server);
3996 }
3997
3998 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3999                           struct cifs_sb_info *cifs_sb, struct smb_vol *vol_info)
4000 {
4001         /* if we are reconnecting then should we check to see if
4002          * any requested capabilities changed locally e.g. via
4003          * remount but we can not do much about it here
4004          * if they have (even if we could detect it by the following)
4005          * Perhaps we could add a backpointer to array of sb from tcon
4006          * or if we change to make all sb to same share the same
4007          * sb as NFS - then we only have one backpointer to sb.
4008          * What if we wanted to mount the server share twice once with
4009          * and once without posixacls or posix paths? */
4010         __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
4011
4012         if (vol_info && vol_info->no_linux_ext) {
4013                 tcon->fsUnixInfo.Capability = 0;
4014                 tcon->unix_ext = 0; /* Unix Extensions disabled */
4015                 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
4016                 return;
4017         } else if (vol_info)
4018                 tcon->unix_ext = 1; /* Unix Extensions supported */
4019
4020         if (tcon->unix_ext == 0) {
4021                 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
4022                 return;
4023         }
4024
4025         if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
4026                 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
4027                 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
4028                 /* check for reconnect case in which we do not
4029                    want to change the mount behavior if we can avoid it */
4030                 if (vol_info == NULL) {
4031                         /* turn off POSIX ACL and PATHNAMES if not set
4032                            originally at mount time */
4033                         if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
4034                                 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
4035                         if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
4036                                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
4037                                         cifs_dbg(VFS, "POSIXPATH support change\n");
4038                                 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
4039                         } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
4040                                 cifs_dbg(VFS, "possible reconnect error\n");
4041                                 cifs_dbg(VFS, "server disabled POSIX path support\n");
4042                         }
4043                 }
4044
4045                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
4046                         cifs_dbg(VFS, "per-share encryption not supported yet\n");
4047
4048                 cap &= CIFS_UNIX_CAP_MASK;
4049                 if (vol_info && vol_info->no_psx_acl)
4050                         cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
4051                 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
4052                         cifs_dbg(FYI, "negotiated posix acl support\n");
4053                         if (cifs_sb)
4054                                 cifs_sb->mnt_cifs_flags |=
4055                                         CIFS_MOUNT_POSIXACL;
4056                 }
4057
4058                 if (vol_info && vol_info->posix_paths == 0)
4059                         cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
4060                 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
4061                         cifs_dbg(FYI, "negotiate posix pathnames\n");
4062                         if (cifs_sb)
4063                                 cifs_sb->mnt_cifs_flags |=
4064                                         CIFS_MOUNT_POSIX_PATHS;
4065                 }
4066
4067                 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
4068 #ifdef CONFIG_CIFS_DEBUG2
4069                 if (cap & CIFS_UNIX_FCNTL_CAP)
4070                         cifs_dbg(FYI, "FCNTL cap\n");
4071                 if (cap & CIFS_UNIX_EXTATTR_CAP)
4072                         cifs_dbg(FYI, "EXTATTR cap\n");
4073                 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
4074                         cifs_dbg(FYI, "POSIX path cap\n");
4075                 if (cap & CIFS_UNIX_XATTR_CAP)
4076                         cifs_dbg(FYI, "XATTR cap\n");
4077                 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
4078                         cifs_dbg(FYI, "POSIX ACL cap\n");
4079                 if (cap & CIFS_UNIX_LARGE_READ_CAP)
4080                         cifs_dbg(FYI, "very large read cap\n");
4081                 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
4082                         cifs_dbg(FYI, "very large write cap\n");
4083                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
4084                         cifs_dbg(FYI, "transport encryption cap\n");
4085                 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
4086                         cifs_dbg(FYI, "mandatory transport encryption cap\n");
4087 #endif /* CIFS_DEBUG2 */
4088                 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
4089                         if (vol_info == NULL) {
4090                                 cifs_dbg(FYI, "resetting capabilities failed\n");
4091                         } else
4092                                 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");
4093
4094                 }
4095         }
4096 }
4097
4098 int cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
4099                         struct cifs_sb_info *cifs_sb)
4100 {
4101         INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
4102
4103         spin_lock_init(&cifs_sb->tlink_tree_lock);
4104         cifs_sb->tlink_tree = RB_ROOT;
4105
4106         cifs_sb->bsize = pvolume_info->bsize;
4107         /*
4108          * Temporarily set r/wsize for matching superblock. If we end up using
4109          * new sb then client will later negotiate it downward if needed.
4110          */
4111         cifs_sb->rsize = pvolume_info->rsize;
4112         cifs_sb->wsize = pvolume_info->wsize;
4113
4114         cifs_sb->mnt_uid = pvolume_info->linux_uid;
4115         cifs_sb->mnt_gid = pvolume_info->linux_gid;
4116         cifs_sb->mnt_file_mode = pvolume_info->file_mode;
4117         cifs_sb->mnt_dir_mode = pvolume_info->dir_mode;
4118         cifs_dbg(FYI, "file mode: %04ho  dir mode: %04ho\n",
4119                  cifs_sb->mnt_file_mode, cifs_sb->mnt_dir_mode);
4120
4121         cifs_sb->actimeo = pvolume_info->actimeo;
4122         cifs_sb->local_nls = pvolume_info->local_nls;
4123
4124         if (pvolume_info->nodfs)
4125                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_DFS;
4126         if (pvolume_info->noperm)
4127                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_PERM;
4128         if (pvolume_info->setuids)
4129                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SET_UID;
4130         if (pvolume_info->setuidfromacl)
4131                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UID_FROM_ACL;
4132         if (pvolume_info->server_ino)
4133                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SERVER_INUM;
4134         if (pvolume_info->remap)
4135                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SFM_CHR;
4136         if (pvolume_info->sfu_remap)
4137                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
4138         if (pvolume_info->no_xattr)
4139                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
4140         if (pvolume_info->sfu_emul)
4141                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UNX_EMUL;
4142         if (pvolume_info->nobrl)
4143                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_BRL;
4144         if (pvolume_info->nohandlecache)
4145                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_HANDLE_CACHE;
4146         if (pvolume_info->nostrictsync)
4147                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOSSYNC;
4148         if (pvolume_info->mand_lock)
4149                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOPOSIXBRL;
4150         if (pvolume_info->rwpidforward)
4151                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RWPIDFORWARD;
4152         if (pvolume_info->mode_ace)
4153                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MODE_FROM_SID;
4154         if (pvolume_info->cifs_acl)
4155                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_ACL;
4156         if (pvolume_info->backupuid_specified) {
4157                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPUID;
4158                 cifs_sb->mnt_backupuid = pvolume_info->backupuid;
4159         }
4160         if (pvolume_info->backupgid_specified) {
4161                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPGID;
4162                 cifs_sb->mnt_backupgid = pvolume_info->backupgid;
4163         }
4164         if (pvolume_info->override_uid)
4165                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
4166         if (pvolume_info->override_gid)
4167                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
4168         if (pvolume_info->dynperm)
4169                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
4170         if (pvolume_info->fsc)
4171                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_FSCACHE;
4172         if (pvolume_info->multiuser)
4173                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_MULTIUSER |
4174                                             CIFS_MOUNT_NO_PERM);
4175         if (pvolume_info->strict_io)
4176                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_STRICT_IO;
4177         if (pvolume_info->direct_io) {
4178                 cifs_dbg(FYI, "mounting share using direct i/o\n");
4179                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DIRECT_IO;
4180         }
4181         if (pvolume_info->cache_ro) {
4182                 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
4183                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
4184         } else if (pvolume_info->cache_rw) {
4185                 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
4186                 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
4187                                             CIFS_MOUNT_RW_CACHE);
4188         }
4189         if (pvolume_info->mfsymlinks) {
4190                 if (pvolume_info->sfu_emul) {
4191                         /*
4192                          * Our SFU ("Services for Unix" emulation does not allow
4193                          * creating symlinks but does allow reading existing SFU
4194                          * symlinks (it does allow both creating and reading SFU
4195                          * style mknod and FIFOs though). When "mfsymlinks" and
4196                          * "sfu" are both enabled at the same time, it allows
4197                          * reading both types of symlinks, but will only create
4198                          * them with mfsymlinks format. This allows better
4199                          * Apple compatibility (probably better for Samba too)
4200                          * while still recognizing old Windows style symlinks.
4201                          */
4202                         cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n");
4203                 }
4204                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
4205         }
4206
4207         if ((pvolume_info->cifs_acl) && (pvolume_info->dynperm))
4208                 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
4209
4210         if (pvolume_info->prepath) {
4211                 cifs_sb->prepath = kstrdup(pvolume_info->prepath, GFP_KERNEL);
4212                 if (cifs_sb->prepath == NULL)
4213                         return -ENOMEM;
4214         }
4215
4216         return 0;
4217 }
4218
4219 void
4220 cifs_cleanup_volume_info_contents(struct smb_vol *volume_info)
4221 {
4222         kfree(volume_info->username);
4223         kfree_sensitive(volume_info->password);
4224         kfree(volume_info->UNC);
4225         kfree(volume_info->domainname);
4226         kfree(volume_info->iocharset);
4227         kfree(volume_info->prepath);
4228 }
4229
4230 void
4231 cifs_cleanup_volume_info(struct smb_vol *volume_info)
4232 {
4233         if (!volume_info)
4234                 return;
4235         cifs_cleanup_volume_info_contents(volume_info);
4236         kfree(volume_info);
4237 }
4238
4239 /* Release all succeed connections */
4240 static inline void mount_put_conns(struct cifs_sb_info *cifs_sb,
4241                                    unsigned int xid,
4242                                    struct TCP_Server_Info *server,
4243                                    struct cifs_ses *ses, struct cifs_tcon *tcon)
4244 {
4245         int rc = 0;
4246
4247         if (tcon)
4248                 cifs_put_tcon(tcon);
4249         else if (ses)
4250                 cifs_put_smb_ses(ses);
4251         else if (server)
4252                 cifs_put_tcp_session(server, 0);
4253         cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
4254         free_xid(xid);
4255 }
4256
4257 /* Get connections for tcp, ses and tcon */
4258 static int mount_get_conns(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
4259                            unsigned int *xid,
4260                            struct TCP_Server_Info **nserver,
4261                            struct cifs_ses **nses, struct cifs_tcon **ntcon)
4262 {
4263         int rc = 0;
4264         struct TCP_Server_Info *server;
4265         struct cifs_ses *ses;
4266         struct cifs_tcon *tcon;
4267
4268         *nserver = NULL;
4269         *nses = NULL;
4270         *ntcon = NULL;
4271
4272         *xid = get_xid();
4273
4274         /* get a reference to a tcp session */
4275         server = cifs_get_tcp_session(vol);
4276         if (IS_ERR(server)) {
4277                 rc = PTR_ERR(server);
4278                 return rc;
4279         }
4280
4281         *nserver = server;
4282
4283         if ((vol->max_credits < 20) || (vol->max_credits > 60000))
4284                 server->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
4285         else
4286                 server->max_credits = vol->max_credits;
4287
4288         /* get a reference to a SMB session */
4289         ses = cifs_get_smb_ses(server, vol);
4290         if (IS_ERR(ses)) {
4291                 rc = PTR_ERR(ses);
4292                 return rc;
4293         }
4294
4295         *nses = ses;
4296
4297         if ((vol->persistent == true) && (!(ses->server->capabilities &
4298                                             SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
4299                 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
4300                 return -EOPNOTSUPP;
4301         }
4302
4303         /* search for existing tcon to this server share */
4304         tcon = cifs_get_tcon(ses, vol);
4305         if (IS_ERR(tcon)) {
4306                 rc = PTR_ERR(tcon);
4307                 return rc;
4308         }
4309
4310         *ntcon = tcon;
4311
4312         /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
4313         if (tcon->posix_extensions)
4314                 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
4315
4316         /* tell server which Unix caps we support */
4317         if (cap_unix(tcon->ses)) {
4318                 /*
4319                  * reset of caps checks mount to see if unix extensions disabled
4320                  * for just this mount.
4321                  */
4322                 reset_cifs_unix_caps(*xid, tcon, cifs_sb, vol);
4323                 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
4324                     (le64_to_cpu(tcon->fsUnixInfo.Capability) &
4325                      CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP))
4326                         return -EACCES;
4327         } else
4328                 tcon->unix_ext = 0; /* server does not support them */
4329
4330         /* do not care if a following call succeed - informational */
4331         if (!tcon->pipe && server->ops->qfs_tcon) {
4332                 server->ops->qfs_tcon(*xid, tcon, cifs_sb);
4333                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
4334                         if (tcon->fsDevInfo.DeviceCharacteristics &
4335                             cpu_to_le32(FILE_READ_ONLY_DEVICE))
4336                                 cifs_dbg(VFS, "mounted to read only share\n");
4337                         else if ((cifs_sb->mnt_cifs_flags &
4338                                   CIFS_MOUNT_RW_CACHE) == 0)
4339                                 cifs_dbg(VFS, "read only mount of RW share\n");
4340                         /* no need to log a RW mount of a typical RW share */
4341                 }
4342         }
4343
4344         cifs_sb->wsize = server->ops->negotiate_wsize(tcon, vol);
4345         cifs_sb->rsize = server->ops->negotiate_rsize(tcon, vol);
4346
4347         return 0;
4348 }
4349
4350 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
4351                              struct cifs_tcon *tcon)
4352 {
4353         struct tcon_link *tlink;
4354
4355         /* hang the tcon off of the superblock */
4356         tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4357         if (tlink == NULL)
4358                 return -ENOMEM;
4359
4360         tlink->tl_uid = ses->linux_uid;
4361         tlink->tl_tcon = tcon;
4362         tlink->tl_time = jiffies;
4363         set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
4364         set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4365
4366         cifs_sb->master_tlink = tlink;
4367         spin_lock(&cifs_sb->tlink_tree_lock);
4368         tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4369         spin_unlock(&cifs_sb->tlink_tree_lock);
4370
4371         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4372                                 TLINK_IDLE_EXPIRE);
4373         return 0;
4374 }
4375
4376 #ifdef CONFIG_CIFS_DFS_UPCALL
4377 /*
4378  * cifs_build_path_to_root returns full path to root when we do not have an
4379  * exiting connection (tcon)
4380  */
4381 static char *
4382 build_unc_path_to_root(const struct smb_vol *vol,
4383                        const struct cifs_sb_info *cifs_sb, bool useppath)
4384 {
4385         char *full_path, *pos;
4386         unsigned int pplen = useppath && vol->prepath ?
4387                 strlen(vol->prepath) + 1 : 0;
4388         unsigned int unc_len = strnlen(vol->UNC, MAX_TREE_SIZE + 1);
4389
4390         if (unc_len > MAX_TREE_SIZE)
4391                 return ERR_PTR(-EINVAL);
4392
4393         full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
4394         if (full_path == NULL)
4395                 return ERR_PTR(-ENOMEM);
4396
4397         memcpy(full_path, vol->UNC, unc_len);
4398         pos = full_path + unc_len;
4399
4400         if (pplen) {
4401                 *pos = CIFS_DIR_SEP(cifs_sb);
4402                 memcpy(pos + 1, vol->prepath, pplen);
4403                 pos += pplen;
4404         }
4405
4406         *pos = '\0'; /* add trailing null */
4407         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
4408         cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
4409         return full_path;
4410 }
4411
4412 /**
4413  * expand_dfs_referral - Perform a dfs referral query and update the cifs_sb
4414  *
4415  *
4416  * If a referral is found, cifs_sb->mountdata will be (re-)allocated
4417  * to a string containing updated options for the submount.  Otherwise it
4418  * will be left untouched.
4419  *
4420  * Returns the rc from get_dfs_path to the caller, which can be used to
4421  * determine whether there were referrals.
4422  */
4423 static int
4424 expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
4425                     struct smb_vol *volume_info, struct cifs_sb_info *cifs_sb,
4426                     char *ref_path)
4427 {
4428         int rc;
4429         struct dfs_info3_param referral = {0};
4430         char *full_path = NULL, *mdata = NULL;
4431
4432         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
4433                 return -EREMOTE;
4434
4435         full_path = build_unc_path_to_root(volume_info, cifs_sb, true);
4436         if (IS_ERR(full_path))
4437                 return PTR_ERR(full_path);
4438
4439         rc = dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb),
4440                             ref_path, &referral, NULL);
4441         if (!rc) {
4442                 char *fake_devname = NULL;
4443
4444                 mdata = cifs_compose_mount_options(cifs_sb->mountdata,
4445                                                    full_path + 1, &referral,
4446                                                    &fake_devname);
4447                 free_dfs_info_param(&referral);
4448
4449                 if (IS_ERR(mdata)) {
4450                         rc = PTR_ERR(mdata);
4451                         mdata = NULL;
4452                 } else {
4453                         cifs_cleanup_volume_info_contents(volume_info);
4454                         rc = cifs_setup_volume_info(volume_info, mdata,
4455                                                     fake_devname, false);
4456                 }
4457                 kfree(fake_devname);
4458                 kfree(cifs_sb->mountdata);
4459                 cifs_sb->mountdata = mdata;
4460         }
4461         kfree(full_path);
4462         return rc;
4463 }
4464
4465 static inline int get_next_dfs_tgt(const char *path,
4466                                    struct dfs_cache_tgt_list *tgt_list,
4467                                    struct dfs_cache_tgt_iterator **tgt_it)
4468 {
4469         if (!*tgt_it)
4470                 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
4471         else
4472                 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
4473         return !*tgt_it ? -EHOSTDOWN : 0;
4474 }
4475
4476 static int update_vol_info(const struct dfs_cache_tgt_iterator *tgt_it,
4477                            struct smb_vol *fake_vol, struct smb_vol *vol)
4478 {
4479         const char *tgt = dfs_cache_get_tgt_name(tgt_it);
4480         int len = strlen(tgt) + 2;
4481         char *new_unc;
4482
4483         new_unc = kmalloc(len, GFP_KERNEL);
4484         if (!new_unc)
4485                 return -ENOMEM;
4486         scnprintf(new_unc, len, "\\%s", tgt);
4487
4488         kfree(vol->UNC);
4489         vol->UNC = new_unc;
4490
4491         if (fake_vol->prepath) {
4492                 kfree(vol->prepath);
4493                 vol->prepath = fake_vol->prepath;
4494                 fake_vol->prepath = NULL;
4495         }
4496         memcpy(&vol->dstaddr, &fake_vol->dstaddr, sizeof(vol->dstaddr));
4497
4498         return 0;
4499 }
4500
4501 static int setup_dfs_tgt_conn(const char *path, const char *full_path,
4502                               const struct dfs_cache_tgt_iterator *tgt_it,
4503                               struct cifs_sb_info *cifs_sb, struct smb_vol *vol, unsigned int *xid,
4504                               struct TCP_Server_Info **server, struct cifs_ses **ses,
4505                               struct cifs_tcon **tcon)
4506 {
4507         int rc;
4508         struct dfs_info3_param ref = {0};
4509         char *mdata = NULL, *fake_devname = NULL;
4510         struct smb_vol fake_vol = {NULL};
4511
4512         cifs_dbg(FYI, "%s: dfs path: %s\n", __func__, path);
4513
4514         rc = dfs_cache_get_tgt_referral(path, tgt_it, &ref);
4515         if (rc)
4516                 return rc;
4517
4518         mdata = cifs_compose_mount_options(cifs_sb->mountdata, full_path + 1, &ref, &fake_devname);
4519         free_dfs_info_param(&ref);
4520
4521         if (IS_ERR(mdata)) {
4522                 rc = PTR_ERR(mdata);
4523                 mdata = NULL;
4524         } else {
4525                 cifs_dbg(FYI, "%s: fake_devname: %s\n", __func__, fake_devname);
4526                 rc = cifs_setup_volume_info(&fake_vol, mdata, fake_devname,
4527                                             false);
4528         }
4529         kfree(mdata);
4530         kfree(fake_devname);
4531
4532         if (!rc) {
4533                 /*
4534                  * We use a 'fake_vol' here because we need pass it down to the
4535                  * mount_{get,put} functions to test connection against new DFS
4536                  * targets.
4537                  */
4538                 mount_put_conns(cifs_sb, *xid, *server, *ses, *tcon);
4539                 rc = mount_get_conns(&fake_vol, cifs_sb, xid, server, ses,
4540                                      tcon);
4541                 if (!rc || (*server && *ses)) {
4542                         /*
4543                          * We were able to connect to new target server.
4544                          * Update current volume info with new target server.
4545                          */
4546                         rc = update_vol_info(tgt_it, &fake_vol, vol);
4547                 }
4548         }
4549         cifs_cleanup_volume_info_contents(&fake_vol);
4550         return rc;
4551 }
4552
4553 static int do_dfs_failover(const char *path, const char *full_path, struct cifs_sb_info *cifs_sb,
4554                            struct smb_vol *vol, struct cifs_ses *root_ses, unsigned int *xid,
4555                            struct TCP_Server_Info **server, struct cifs_ses **ses,
4556                            struct cifs_tcon **tcon)
4557 {
4558         int rc;
4559         struct dfs_cache_tgt_list tgt_list;
4560         struct dfs_cache_tgt_iterator *tgt_it = NULL;
4561
4562         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
4563                 return -EOPNOTSUPP;
4564
4565         rc = dfs_cache_noreq_find(path, NULL, &tgt_list);
4566         if (rc)
4567                 return rc;
4568
4569         for (;;) {
4570                 /* Get next DFS target server - if any */
4571                 rc = get_next_dfs_tgt(path, &tgt_list, &tgt_it);
4572                 if (rc)
4573                         break;
4574                 /* Connect to next DFS target */
4575                 rc = setup_dfs_tgt_conn(path, full_path, tgt_it, cifs_sb, vol, xid, server, ses,
4576                                         tcon);
4577                 if (!rc || (*server && *ses))
4578                         break;
4579         }
4580         if (!rc) {
4581                 /*
4582                  * Update DFS target hint in DFS referral cache with the target
4583                  * server we successfully reconnected to.
4584                  */
4585                 rc = dfs_cache_update_tgthint(*xid, root_ses ? root_ses : *ses,
4586                                               cifs_sb->local_nls,
4587                                               cifs_remap(cifs_sb), path,
4588                                               tgt_it);
4589         }
4590         dfs_cache_free_tgts(&tgt_list);
4591         return rc;
4592 }
4593 #endif
4594
4595 int
4596 cifs_setup_volume_info(struct smb_vol *volume_info, char *mount_data,
4597                         const char *devname, bool is_smb3)
4598 {
4599         int rc = 0;
4600
4601         if (cifs_parse_mount_options(mount_data, devname, volume_info, is_smb3))
4602                 return -EINVAL;
4603
4604         if (volume_info->nullauth) {
4605                 cifs_dbg(FYI, "Anonymous login\n");
4606                 kfree(volume_info->username);
4607                 volume_info->username = NULL;
4608         } else if (volume_info->username) {
4609                 /* BB fixme parse for domain name here */
4610                 cifs_dbg(FYI, "Username: %s\n", volume_info->username);
4611         } else {
4612                 cifs_dbg(VFS, "No username specified\n");
4613         /* In userspace mount helper we can get user name from alternate
4614            locations such as env variables and files on disk */
4615                 return -EINVAL;
4616         }
4617
4618         /* this is needed for ASCII cp to Unicode converts */
4619         if (volume_info->iocharset == NULL) {
4620                 /* load_nls_default cannot return null */
4621                 volume_info->local_nls = load_nls_default();
4622         } else {
4623                 volume_info->local_nls = load_nls(volume_info->iocharset);
4624                 if (volume_info->local_nls == NULL) {
4625                         cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
4626                                  volume_info->iocharset);
4627                         return -ELIBACC;
4628                 }
4629         }
4630
4631         return rc;
4632 }
4633
4634 struct smb_vol *
4635 cifs_get_volume_info(char *mount_data, const char *devname, bool is_smb3)
4636 {
4637         int rc;
4638         struct smb_vol *volume_info;
4639
4640         volume_info = kmalloc(sizeof(struct smb_vol), GFP_KERNEL);
4641         if (!volume_info)
4642                 return ERR_PTR(-ENOMEM);
4643
4644         rc = cifs_setup_volume_info(volume_info, mount_data, devname, is_smb3);
4645         if (rc) {
4646                 cifs_cleanup_volume_info(volume_info);
4647                 volume_info = ERR_PTR(rc);
4648         }
4649
4650         return volume_info;
4651 }
4652
4653 static int
4654 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
4655                                         unsigned int xid,
4656                                         struct cifs_tcon *tcon,
4657                                         struct cifs_sb_info *cifs_sb,
4658                                         char *full_path,
4659                                         int added_treename)
4660 {
4661         int rc;
4662         char *s;
4663         char sep, tmp;
4664         int skip = added_treename ? 1 : 0;
4665
4666         sep = CIFS_DIR_SEP(cifs_sb);
4667         s = full_path;
4668
4669         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
4670         while (rc == 0) {
4671                 /* skip separators */
4672                 while (*s == sep)
4673                         s++;
4674                 if (!*s)
4675                         break;
4676                 /* next separator */
4677                 while (*s && *s != sep)
4678                         s++;
4679                 /*
4680                  * if the treename is added, we then have to skip the first
4681                  * part within the separators
4682                  */
4683                 if (skip) {
4684                         skip = 0;
4685                         continue;
4686                 }
4687                 /*
4688                  * temporarily null-terminate the path at the end of
4689                  * the current component
4690                  */
4691                 tmp = *s;
4692                 *s = 0;
4693                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
4694                                                      full_path);
4695                 *s = tmp;
4696         }
4697         return rc;
4698 }
4699
4700 /*
4701  * Check if path is remote (e.g. a DFS share). Return -EREMOTE if it is,
4702  * otherwise 0.
4703  */
4704 static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb_vol *vol,
4705                           const unsigned int xid,
4706                           struct TCP_Server_Info *server,
4707                           struct cifs_tcon *tcon)
4708 {
4709         int rc;
4710         char *full_path;
4711
4712         if (!server->ops->is_path_accessible)
4713                 return -EOPNOTSUPP;
4714
4715         /*
4716          * cifs_build_path_to_root works only when we have a valid tcon
4717          */
4718         full_path = cifs_build_path_to_root(vol, cifs_sb, tcon,
4719                                             tcon->Flags & SMB_SHARE_IS_IN_DFS);
4720         if (full_path == NULL)
4721                 return -ENOMEM;
4722
4723         cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
4724
4725         rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
4726                                              full_path);
4727         if (rc != 0 && rc != -EREMOTE) {
4728                 kfree(full_path);
4729                 return rc;
4730         }
4731
4732         if (rc != -EREMOTE) {
4733                 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
4734                         cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
4735                 if (rc != 0) {
4736                         cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
4737                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
4738                         rc = 0;
4739                 }
4740         }
4741
4742         kfree(full_path);
4743         return rc;
4744 }
4745
4746 #ifdef CONFIG_CIFS_DFS_UPCALL
4747 static void set_root_ses(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
4748                          struct cifs_ses **root_ses)
4749 {
4750         if (ses) {
4751                 spin_lock(&cifs_tcp_ses_lock);
4752                 ses->ses_count++;
4753                 ses->tcon_ipc->remap = cifs_remap(cifs_sb);
4754                 spin_unlock(&cifs_tcp_ses_lock);
4755         }
4756         *root_ses = ses;
4757 }
4758
4759 static void put_root_ses(struct cifs_ses *ses)
4760 {
4761         if (ses)
4762                 cifs_put_smb_ses(ses);
4763 }
4764
4765 /* Check if a path component is remote and then update @dfs_path accordingly */
4766 static int check_dfs_prepath(struct cifs_sb_info *cifs_sb, struct smb_vol *vol,
4767                              const unsigned int xid, struct TCP_Server_Info *server,
4768                              struct cifs_tcon *tcon, char **dfs_path)
4769 {
4770         char *path, *s;
4771         char sep = CIFS_DIR_SEP(cifs_sb), tmp;
4772         char *npath;
4773         int rc = 0;
4774         int added_treename = tcon->Flags & SMB_SHARE_IS_IN_DFS;
4775         int skip = added_treename;
4776
4777         path = cifs_build_path_to_root(vol, cifs_sb, tcon, added_treename);
4778         if (!path)
4779                 return -ENOMEM;
4780
4781         /*
4782          * Walk through the path components in @path and check if they're accessible. In case any of
4783          * the components is -EREMOTE, then update @dfs_path with the next DFS referral request path
4784          * (NOT including the remaining components).
4785          */
4786         s = path;
4787         do {
4788                 /* skip separators */
4789                 while (*s && *s == sep)
4790                         s++;
4791                 if (!*s)
4792                         break;
4793                 /* next separator */
4794                 while (*s && *s != sep)
4795                         s++;
4796                 /*
4797                  * if the treename is added, we then have to skip the first
4798                  * part within the separators
4799                  */
4800                 if (skip) {
4801                         skip = 0;
4802                         continue;
4803                 }
4804                 tmp = *s;
4805                 *s = 0;
4806                 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, path);
4807                 if (rc && rc == -EREMOTE) {
4808                         struct smb_vol v = {NULL};
4809                         /* if @path contains a tree name, skip it in the prefix path */
4810                         if (added_treename) {
4811                                 rc = cifs_parse_devname(path, &v);
4812                                 if (rc)
4813                                         break;
4814                                 rc = -EREMOTE;
4815                                 npath = build_unc_path_to_root(&v, cifs_sb, true);
4816                                 cifs_cleanup_volume_info_contents(&v);
4817                         } else {
4818                                 v.UNC = vol->UNC;
4819                                 v.prepath = path + 1;
4820                                 npath = build_unc_path_to_root(&v, cifs_sb, true);
4821                         }
4822                         if (IS_ERR(npath)) {
4823                                 rc = PTR_ERR(npath);
4824                                 break;
4825                         }
4826                         kfree(*dfs_path);
4827                         *dfs_path = npath;
4828                 }
4829                 *s = tmp;
4830         } while (rc == 0);
4831
4832         kfree(path);
4833         return rc;
4834 }
4835
4836 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol)
4837 {
4838         int rc = 0;
4839         unsigned int xid;
4840         struct TCP_Server_Info *server = NULL;
4841         struct cifs_ses *ses = NULL, *root_ses = NULL;
4842         struct cifs_tcon *tcon = NULL;
4843         int count = 0;
4844         char *ref_path = NULL, *full_path = NULL;
4845         char *oldmnt = NULL;
4846         char *mntdata = NULL;
4847
4848         rc = mount_get_conns(vol, cifs_sb, &xid, &server, &ses, &tcon);
4849         /*
4850          * Unconditionally try to get an DFS referral (even cached) to determine whether it is an
4851          * DFS mount.
4852          *
4853          * Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
4854          * to respond with PATH_NOT_COVERED to requests that include the prefix.
4855          */
4856         if (dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb), vol->UNC + 1, NULL,
4857                            NULL)) {
4858                 /* No DFS referral was returned.  Looks like a regular share. */
4859                 if (rc)
4860                         goto error;
4861                 /* Check if it is fully accessible and then mount it */
4862                 rc = is_path_remote(cifs_sb, vol, xid, server, tcon);
4863                 if (!rc)
4864                         goto out;
4865                 if (rc != -EREMOTE)
4866                         goto error;
4867         }
4868         /* Save mount options */
4869         mntdata = kstrndup(cifs_sb->mountdata, strlen(cifs_sb->mountdata), GFP_KERNEL);
4870         if (!mntdata) {
4871                 rc = -ENOMEM;
4872                 goto error;
4873         }
4874         /* Get path of DFS root */
4875         ref_path = build_unc_path_to_root(vol, cifs_sb, false);
4876         if (IS_ERR(ref_path)) {
4877                 rc = PTR_ERR(ref_path);
4878                 ref_path = NULL;
4879                 goto error;
4880         }
4881
4882         set_root_ses(cifs_sb, ses, &root_ses);
4883         do {
4884                 /* Save full path of last DFS path we used to resolve final target server */
4885                 kfree(full_path);
4886                 full_path = build_unc_path_to_root(vol, cifs_sb, !!count);
4887                 if (IS_ERR(full_path)) {
4888                         rc = PTR_ERR(full_path);
4889                         full_path = NULL;
4890                         break;
4891                 }
4892                 /* Chase referral */
4893                 oldmnt = cifs_sb->mountdata;
4894                 rc = expand_dfs_referral(xid, root_ses, vol, cifs_sb, ref_path + 1);
4895                 if (rc)
4896                         break;
4897                 /* Connect to new DFS target only if we were redirected */
4898                 if (oldmnt != cifs_sb->mountdata) {
4899                         mount_put_conns(cifs_sb, xid, server, ses, tcon);
4900                         rc = mount_get_conns(vol, cifs_sb, &xid, &server, &ses, &tcon);
4901                 }
4902                 if (rc && !server && !ses) {
4903                         /* Failed to connect. Try to connect to other targets in the referral. */
4904                         rc = do_dfs_failover(ref_path + 1, full_path, cifs_sb, vol, root_ses, &xid,
4905                                              &server, &ses, &tcon);
4906                 }
4907                 if (rc == -EACCES || rc == -EOPNOTSUPP || !server || !ses)
4908                         break;
4909                 if (!tcon)
4910                         continue;
4911                 /* Make sure that requests go through new root servers */
4912                 if (is_tcon_dfs(tcon)) {
4913                         put_root_ses(root_ses);
4914                         set_root_ses(cifs_sb, ses, &root_ses);
4915                 }
4916                 /* Check for remaining path components and then continue chasing them (-EREMOTE) */
4917                 rc = check_dfs_prepath(cifs_sb, vol, xid, server, tcon, &ref_path);
4918                 /* Prevent recursion on broken link referrals */
4919                 if (rc == -EREMOTE && ++count > MAX_NESTED_LINKS)
4920                         rc = -ELOOP;
4921         } while (rc == -EREMOTE);
4922
4923         if (rc)
4924                 goto error;
4925         put_root_ses(root_ses);
4926         root_ses = NULL;
4927         kfree(ref_path);
4928         ref_path = NULL;
4929         /*
4930          * Store DFS full path in both superblock and tree connect structures.
4931          *
4932          * For DFS root mounts, the prefix path (cifs_sb->prepath) is preserved during reconnect so
4933          * only the root path is set in cifs_sb->origin_fullpath and tcon->dfs_path. And for DFS
4934          * links, the prefix path is included in both and may be changed during reconnect.  See
4935          * cifs_tree_connect().
4936          */
4937         cifs_sb->origin_fullpath = kstrndup(full_path, strlen(full_path), GFP_KERNEL);
4938         if (!cifs_sb->origin_fullpath) {
4939                 rc = -ENOMEM;
4940                 goto error;
4941         }
4942         spin_lock(&cifs_tcp_ses_lock);
4943         tcon->dfs_path = full_path;
4944         full_path = NULL;
4945         tcon->remap = cifs_remap(cifs_sb);
4946         spin_unlock(&cifs_tcp_ses_lock);
4947
4948         /* Add original volume information for DFS cache to be used when refreshing referrals */
4949         rc = dfs_cache_add_vol(mntdata, vol, cifs_sb->origin_fullpath);
4950         if (rc)
4951                 goto error;
4952         /*
4953          * After reconnecting to a different server, unique ids won't
4954          * match anymore, so we disable serverino. This prevents
4955          * dentry revalidation to think the dentry are stale (ESTALE).
4956          */
4957         cifs_autodisable_serverino(cifs_sb);
4958         /*
4959          * Force the use of prefix path to support failover on DFS paths that
4960          * resolve to targets that have different prefix paths.
4961          */
4962         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
4963         kfree(cifs_sb->prepath);
4964         cifs_sb->prepath = vol->prepath;
4965         vol->prepath = NULL;
4966
4967 out:
4968         free_xid(xid);
4969         cifs_try_adding_channels(ses);
4970         return mount_setup_tlink(cifs_sb, ses, tcon);
4971
4972 error:
4973         kfree(ref_path);
4974         kfree(full_path);
4975         kfree(mntdata);
4976         kfree(cifs_sb->origin_fullpath);
4977         put_root_ses(root_ses);
4978         mount_put_conns(cifs_sb, xid, server, ses, tcon);
4979         return rc;
4980 }
4981 #else
4982 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *vol)
4983 {
4984         int rc = 0;
4985         unsigned int xid;
4986         struct cifs_ses *ses;
4987         struct cifs_tcon *tcon;
4988         struct TCP_Server_Info *server;
4989
4990         rc = mount_get_conns(vol, cifs_sb, &xid, &server, &ses, &tcon);
4991         if (rc)
4992                 goto error;
4993
4994         if (tcon) {
4995                 rc = is_path_remote(cifs_sb, vol, xid, server, tcon);
4996                 if (rc == -EREMOTE)
4997                         rc = -EOPNOTSUPP;
4998                 if (rc)
4999                         goto error;
5000         }
5001
5002         free_xid(xid);
5003
5004         return mount_setup_tlink(cifs_sb, ses, tcon);
5005
5006 error:
5007         mount_put_conns(cifs_sb, xid, server, ses, tcon);
5008         return rc;
5009 }
5010 #endif
5011
5012 /*
5013  * Issue a TREE_CONNECT request.
5014  */
5015 int
5016 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
5017          const char *tree, struct cifs_tcon *tcon,
5018          const struct nls_table *nls_codepage)
5019 {
5020         struct smb_hdr *smb_buffer;
5021         struct smb_hdr *smb_buffer_response;
5022         TCONX_REQ *pSMB;
5023         TCONX_RSP *pSMBr;
5024         unsigned char *bcc_ptr;
5025         int rc = 0;
5026         int length;
5027         __u16 bytes_left, count;
5028
5029         if (ses == NULL)
5030                 return -EIO;
5031
5032         smb_buffer = cifs_buf_get();
5033         if (smb_buffer == NULL)
5034                 return -ENOMEM;
5035
5036         smb_buffer_response = smb_buffer;
5037
5038         header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
5039                         NULL /*no tid */ , 4 /*wct */ );
5040
5041         smb_buffer->Mid = get_next_mid(ses->server);
5042         smb_buffer->Uid = ses->Suid;
5043         pSMB = (TCONX_REQ *) smb_buffer;
5044         pSMBr = (TCONX_RSP *) smb_buffer_response;
5045
5046         pSMB->AndXCommand = 0xFF;
5047         pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
5048         bcc_ptr = &pSMB->Password[0];
5049         if (tcon->pipe || (ses->server->sec_mode & SECMODE_USER)) {
5050                 pSMB->PasswordLength = cpu_to_le16(1);  /* minimum */
5051                 *bcc_ptr = 0; /* password is null byte */
5052                 bcc_ptr++;              /* skip password */
5053                 /* already aligned so no need to do it below */
5054         } else {
5055                 pSMB->PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
5056                 /* BB FIXME add code to fail this if NTLMv2 or Kerberos
5057                    specified as required (when that support is added to
5058                    the vfs in the future) as only NTLM or the much
5059                    weaker LANMAN (which we do not send by default) is accepted
5060                    by Samba (not sure whether other servers allow
5061                    NTLMv2 password here) */
5062 #ifdef CONFIG_CIFS_WEAK_PW_HASH
5063                 if ((global_secflags & CIFSSEC_MAY_LANMAN) &&
5064                     (ses->sectype == LANMAN))
5065                         calc_lanman_hash(tcon->password, ses->server->cryptkey,
5066                                          ses->server->sec_mode &
5067                                             SECMODE_PW_ENCRYPT ? true : false,
5068                                          bcc_ptr);
5069                 else
5070 #endif /* CIFS_WEAK_PW_HASH */
5071                 rc = SMBNTencrypt(tcon->password, ses->server->cryptkey,
5072                                         bcc_ptr, nls_codepage);
5073                 if (rc) {
5074                         cifs_dbg(FYI, "%s Can't generate NTLM rsp. Error: %d\n",
5075                                  __func__, rc);
5076                         cifs_buf_release(smb_buffer);
5077                         return rc;
5078                 }
5079
5080                 bcc_ptr += CIFS_AUTH_RESP_SIZE;
5081                 if (ses->capabilities & CAP_UNICODE) {
5082                         /* must align unicode strings */
5083                         *bcc_ptr = 0; /* null byte password */
5084                         bcc_ptr++;
5085                 }
5086         }
5087
5088         if (ses->server->sign)
5089                 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
5090
5091         if (ses->capabilities & CAP_STATUS32) {
5092                 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
5093         }
5094         if (ses->capabilities & CAP_DFS) {
5095                 smb_buffer->Flags2 |= SMBFLG2_DFS;
5096         }
5097         if (ses->capabilities & CAP_UNICODE) {
5098                 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
5099                 length =
5100                     cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
5101                         6 /* max utf8 char length in bytes */ *
5102                         (/* server len*/ + 256 /* share len */), nls_codepage);
5103                 bcc_ptr += 2 * length;  /* convert num 16 bit words to bytes */
5104                 bcc_ptr += 2;   /* skip trailing null */
5105         } else {                /* ASCII */
5106                 strcpy(bcc_ptr, tree);
5107                 bcc_ptr += strlen(tree) + 1;
5108         }
5109         strcpy(bcc_ptr, "?????");
5110         bcc_ptr += strlen("?????");
5111         bcc_ptr += 1;
5112         count = bcc_ptr - &pSMB->Password[0];
5113         be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
5114         pSMB->ByteCount = cpu_to_le16(count);
5115
5116         rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
5117                          0);
5118
5119         /* above now done in SendReceive */
5120         if (rc == 0) {
5121                 bool is_unicode;
5122
5123                 tcon->tidStatus = CifsGood;
5124                 tcon->need_reconnect = false;
5125                 tcon->tid = smb_buffer_response->Tid;
5126                 bcc_ptr = pByteArea(smb_buffer_response);
5127                 bytes_left = get_bcc(smb_buffer_response);
5128                 length = strnlen(bcc_ptr, bytes_left - 2);
5129                 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
5130                         is_unicode = true;
5131                 else
5132                         is_unicode = false;
5133
5134
5135                 /* skip service field (NB: this field is always ASCII) */
5136                 if (length == 3) {
5137                         if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
5138                             (bcc_ptr[2] == 'C')) {
5139                                 cifs_dbg(FYI, "IPC connection\n");
5140                                 tcon->ipc = true;
5141                                 tcon->pipe = true;
5142                         }
5143                 } else if (length == 2) {
5144                         if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
5145                                 /* the most common case */
5146                                 cifs_dbg(FYI, "disk share connection\n");
5147                         }
5148                 }
5149                 bcc_ptr += length + 1;
5150                 bytes_left -= (length + 1);
5151                 strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
5152
5153                 /* mostly informational -- no need to fail on error here */
5154                 kfree(tcon->nativeFileSystem);
5155                 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
5156                                                       bytes_left, is_unicode,
5157                                                       nls_codepage);
5158
5159                 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
5160
5161                 if ((smb_buffer_response->WordCount == 3) ||
5162                          (smb_buffer_response->WordCount == 7))
5163                         /* field is in same location */
5164                         tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
5165                 else
5166                         tcon->Flags = 0;
5167                 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
5168         }
5169
5170         cifs_buf_release(smb_buffer);
5171         return rc;
5172 }
5173
5174 static void delayed_free(struct rcu_head *p)
5175 {
5176         struct cifs_sb_info *sbi = container_of(p, struct cifs_sb_info, rcu);
5177         unload_nls(sbi->local_nls);
5178         kfree(sbi);
5179 }
5180
5181 void
5182 cifs_umount(struct cifs_sb_info *cifs_sb)
5183 {
5184         struct rb_root *root = &cifs_sb->tlink_tree;
5185         struct rb_node *node;
5186         struct tcon_link *tlink;
5187
5188         cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
5189
5190         spin_lock(&cifs_sb->tlink_tree_lock);
5191         while ((node = rb_first(root))) {
5192                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
5193                 cifs_get_tlink(tlink);
5194                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
5195                 rb_erase(node, root);
5196
5197                 spin_unlock(&cifs_sb->tlink_tree_lock);
5198                 cifs_put_tlink(tlink);
5199                 spin_lock(&cifs_sb->tlink_tree_lock);
5200         }
5201         spin_unlock(&cifs_sb->tlink_tree_lock);
5202
5203         kfree(cifs_sb->mountdata);
5204         kfree(cifs_sb->prepath);
5205 #ifdef CONFIG_CIFS_DFS_UPCALL
5206         dfs_cache_del_vol(cifs_sb->origin_fullpath);
5207         kfree(cifs_sb->origin_fullpath);
5208 #endif
5209         call_rcu(&cifs_sb->rcu, delayed_free);
5210 }
5211
5212 int
5213 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
5214 {
5215         int rc = 0;
5216         struct TCP_Server_Info *server = cifs_ses_server(ses);
5217
5218         if (!server->ops->need_neg || !server->ops->negotiate)
5219                 return -ENOSYS;
5220
5221         /* only send once per connect */
5222         if (!server->ops->need_neg(server))
5223                 return 0;
5224
5225         rc = server->ops->negotiate(xid, ses);
5226         if (rc == 0) {
5227                 spin_lock(&GlobalMid_Lock);
5228                 if (server->tcpStatus == CifsNeedNegotiate)
5229                         server->tcpStatus = CifsGood;
5230                 else
5231                         rc = -EHOSTDOWN;
5232                 spin_unlock(&GlobalMid_Lock);
5233         }
5234
5235         return rc;
5236 }
5237
5238 int
5239 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
5240                    struct nls_table *nls_info)
5241 {
5242         int rc = -ENOSYS;
5243         struct TCP_Server_Info *server = cifs_ses_server(ses);
5244
5245         if (!ses->binding) {
5246                 ses->capabilities = server->capabilities;
5247                 if (linuxExtEnabled == 0)
5248                         ses->capabilities &= (~server->vals->cap_unix);
5249
5250                 if (ses->auth_key.response) {
5251                         cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
5252                                  ses->auth_key.response);
5253                         kfree(ses->auth_key.response);
5254                         ses->auth_key.response = NULL;
5255                         ses->auth_key.len = 0;
5256                 }
5257         }
5258
5259         cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
5260                  server->sec_mode, server->capabilities, server->timeAdj);
5261
5262         if (server->ops->sess_setup)
5263                 rc = server->ops->sess_setup(xid, ses, nls_info);
5264
5265         if (rc)
5266                 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
5267
5268         return rc;
5269 }
5270
5271 static int
5272 cifs_set_vol_auth(struct smb_vol *vol, struct cifs_ses *ses)
5273 {
5274         vol->sectype = ses->sectype;
5275
5276         /* krb5 is special, since we don't need username or pw */
5277         if (vol->sectype == Kerberos)
5278                 return 0;
5279
5280         return cifs_set_cifscreds(vol, ses);
5281 }
5282
5283 static struct cifs_tcon *
5284 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
5285 {
5286         int rc;
5287         struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
5288         struct cifs_ses *ses;
5289         struct cifs_tcon *tcon = NULL;
5290         struct smb_vol *vol_info;
5291
5292         vol_info = kzalloc(sizeof(*vol_info), GFP_KERNEL);
5293         if (vol_info == NULL)
5294                 return ERR_PTR(-ENOMEM);
5295
5296         vol_info->local_nls = cifs_sb->local_nls;
5297         vol_info->linux_uid = fsuid;
5298         vol_info->cred_uid = fsuid;
5299         vol_info->UNC = master_tcon->treeName;
5300         vol_info->retry = master_tcon->retry;
5301         vol_info->nocase = master_tcon->nocase;
5302         vol_info->nohandlecache = master_tcon->nohandlecache;
5303         vol_info->local_lease = master_tcon->local_lease;
5304         vol_info->no_lease = master_tcon->no_lease;
5305         vol_info->resilient = master_tcon->use_resilient;
5306         vol_info->persistent = master_tcon->use_persistent;
5307         vol_info->handle_timeout = master_tcon->handle_timeout;
5308         vol_info->no_linux_ext = !master_tcon->unix_ext;
5309         vol_info->linux_ext = master_tcon->posix_extensions;
5310         vol_info->sectype = master_tcon->ses->sectype;
5311         vol_info->sign = master_tcon->ses->sign;
5312         vol_info->seal = master_tcon->seal;
5313
5314         rc = cifs_set_vol_auth(vol_info, master_tcon->ses);
5315         if (rc) {
5316                 tcon = ERR_PTR(rc);
5317                 goto out;
5318         }
5319
5320         /* get a reference for the same TCP session */
5321         spin_lock(&cifs_tcp_ses_lock);
5322         ++master_tcon->ses->server->srv_count;
5323         spin_unlock(&cifs_tcp_ses_lock);
5324
5325         ses = cifs_get_smb_ses(master_tcon->ses->server, vol_info);
5326         if (IS_ERR(ses)) {
5327                 tcon = (struct cifs_tcon *)ses;
5328                 cifs_put_tcp_session(master_tcon->ses->server, 0);
5329                 goto out;
5330         }
5331
5332         tcon = cifs_get_tcon(ses, vol_info);
5333         if (IS_ERR(tcon)) {
5334                 cifs_put_smb_ses(ses);
5335                 goto out;
5336         }
5337
5338         if (cap_unix(ses))
5339                 reset_cifs_unix_caps(0, tcon, NULL, vol_info);
5340
5341 out:
5342         kfree(vol_info->username);
5343         kfree_sensitive(vol_info->password);
5344         kfree(vol_info);
5345
5346         return tcon;
5347 }
5348
5349 struct cifs_tcon *
5350 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
5351 {
5352         return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
5353 }
5354
5355 /* find and return a tlink with given uid */
5356 static struct tcon_link *
5357 tlink_rb_search(struct rb_root *root, kuid_t uid)
5358 {
5359         struct rb_node *node = root->rb_node;
5360         struct tcon_link *tlink;
5361
5362         while (node) {
5363                 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
5364
5365                 if (uid_gt(tlink->tl_uid, uid))
5366                         node = node->rb_left;
5367                 else if (uid_lt(tlink->tl_uid, uid))
5368                         node = node->rb_right;
5369                 else
5370                         return tlink;
5371         }
5372         return NULL;
5373 }
5374
5375 /* insert a tcon_link into the tree */
5376 static void
5377 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
5378 {
5379         struct rb_node **new = &(root->rb_node), *parent = NULL;
5380         struct tcon_link *tlink;
5381
5382         while (*new) {
5383                 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
5384                 parent = *new;
5385
5386                 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
5387                         new = &((*new)->rb_left);
5388                 else
5389                         new = &((*new)->rb_right);
5390         }
5391
5392         rb_link_node(&new_tlink->tl_rbnode, parent, new);
5393         rb_insert_color(&new_tlink->tl_rbnode, root);
5394 }
5395
5396 /*
5397  * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
5398  * current task.
5399  *
5400  * If the superblock doesn't refer to a multiuser mount, then just return
5401  * the master tcon for the mount.
5402  *
5403  * First, search the rbtree for an existing tcon for this fsuid. If one
5404  * exists, then check to see if it's pending construction. If it is then wait
5405  * for construction to complete. Once it's no longer pending, check to see if
5406  * it failed and either return an error or retry construction, depending on
5407  * the timeout.
5408  *
5409  * If one doesn't exist then insert a new tcon_link struct into the tree and
5410  * try to construct a new one.
5411  */
5412 struct tcon_link *
5413 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
5414 {
5415         int ret;
5416         kuid_t fsuid = current_fsuid();
5417         struct tcon_link *tlink, *newtlink;
5418
5419         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
5420                 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
5421
5422         spin_lock(&cifs_sb->tlink_tree_lock);
5423         tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
5424         if (tlink)
5425                 cifs_get_tlink(tlink);
5426         spin_unlock(&cifs_sb->tlink_tree_lock);
5427
5428         if (tlink == NULL) {
5429                 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
5430                 if (newtlink == NULL)
5431                         return ERR_PTR(-ENOMEM);
5432                 newtlink->tl_uid = fsuid;
5433                 newtlink->tl_tcon = ERR_PTR(-EACCES);
5434                 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
5435                 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
5436                 cifs_get_tlink(newtlink);
5437
5438                 spin_lock(&cifs_sb->tlink_tree_lock);
5439                 /* was one inserted after previous search? */
5440                 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
5441                 if (tlink) {
5442                         cifs_get_tlink(tlink);
5443                         spin_unlock(&cifs_sb->tlink_tree_lock);
5444                         kfree(newtlink);
5445                         goto wait_for_construction;
5446                 }
5447                 tlink = newtlink;
5448                 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
5449                 spin_unlock(&cifs_sb->tlink_tree_lock);
5450         } else {
5451 wait_for_construction:
5452                 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
5453                                   TASK_INTERRUPTIBLE);
5454                 if (ret) {
5455                         cifs_put_tlink(tlink);
5456                         return ERR_PTR(-ERESTARTSYS);
5457                 }
5458
5459                 /* if it's good, return it */
5460                 if (!IS_ERR(tlink->tl_tcon))
5461                         return tlink;
5462
5463                 /* return error if we tried this already recently */
5464                 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
5465                         cifs_put_tlink(tlink);
5466                         return ERR_PTR(-EACCES);
5467                 }
5468
5469                 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
5470                         goto wait_for_construction;
5471         }
5472
5473         tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
5474         clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
5475         wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
5476
5477         if (IS_ERR(tlink->tl_tcon)) {
5478                 cifs_put_tlink(tlink);
5479                 return ERR_PTR(-EACCES);
5480         }
5481
5482         return tlink;
5483 }
5484
5485 /*
5486  * periodic workqueue job that scans tcon_tree for a superblock and closes
5487  * out tcons.
5488  */
5489 static void
5490 cifs_prune_tlinks(struct work_struct *work)
5491 {
5492         struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
5493                                                     prune_tlinks.work);
5494         struct rb_root *root = &cifs_sb->tlink_tree;
5495         struct rb_node *node;
5496         struct rb_node *tmp;
5497         struct tcon_link *tlink;
5498
5499         /*
5500          * Because we drop the spinlock in the loop in order to put the tlink
5501          * it's not guarded against removal of links from the tree. The only
5502          * places that remove entries from the tree are this function and
5503          * umounts. Because this function is non-reentrant and is canceled
5504          * before umount can proceed, this is safe.
5505          */
5506         spin_lock(&cifs_sb->tlink_tree_lock);
5507         node = rb_first(root);
5508         while (node != NULL) {
5509                 tmp = node;
5510                 node = rb_next(tmp);
5511                 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
5512
5513                 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
5514                     atomic_read(&tlink->tl_count) != 0 ||
5515                     time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
5516                         continue;
5517
5518                 cifs_get_tlink(tlink);
5519                 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
5520                 rb_erase(tmp, root);
5521
5522                 spin_unlock(&cifs_sb->tlink_tree_lock);
5523                 cifs_put_tlink(tlink);
5524                 spin_lock(&cifs_sb->tlink_tree_lock);
5525         }
5526         spin_unlock(&cifs_sb->tlink_tree_lock);
5527
5528         queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
5529                                 TLINK_IDLE_EXPIRE);
5530 }
5531
5532 #ifdef CONFIG_CIFS_DFS_UPCALL
5533 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
5534 {
5535         int rc;
5536         struct TCP_Server_Info *server = tcon->ses->server;
5537         const struct smb_version_operations *ops = server->ops;
5538         struct dfs_cache_tgt_list tl;
5539         struct dfs_cache_tgt_iterator *it = NULL;
5540         char *tree;
5541         const char *tcp_host;
5542         size_t tcp_host_len;
5543         const char *dfs_host;
5544         size_t dfs_host_len;
5545         char *share = NULL, *prefix = NULL;
5546         struct dfs_info3_param ref = {0};
5547         bool isroot;
5548
5549         tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);
5550         if (!tree)
5551                 return -ENOMEM;
5552
5553         if (!tcon->dfs_path) {
5554                 if (tcon->ipc) {
5555                         scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
5556                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
5557                 } else {
5558                         rc = ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
5559                 }
5560                 goto out;
5561         }
5562
5563         rc = dfs_cache_noreq_find(tcon->dfs_path + 1, &ref, &tl);
5564         if (rc)
5565                 goto out;
5566         isroot = ref.server_type == DFS_TYPE_ROOT;
5567         free_dfs_info_param(&ref);
5568
5569         extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);
5570
5571         for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) {
5572                 bool target_match;
5573
5574                 kfree(share);
5575                 kfree(prefix);
5576                 share = NULL;
5577                 prefix = NULL;
5578
5579                 rc = dfs_cache_get_tgt_share(tcon->dfs_path + 1, it, &share, &prefix);
5580                 if (rc) {
5581                         cifs_dbg(VFS, "%s: failed to parse target share %d\n",
5582                                  __func__, rc);
5583                         continue;
5584                 }
5585
5586                 extract_unc_hostname(share, &dfs_host, &dfs_host_len);
5587
5588                 if (dfs_host_len != tcp_host_len
5589                     || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) {
5590                         cifs_dbg(FYI, "%s: %.*s doesn't match %.*s\n", __func__, (int)dfs_host_len,
5591                                  dfs_host, (int)tcp_host_len, tcp_host);
5592
5593                         rc = match_target_ip(server, dfs_host, dfs_host_len, &target_match);
5594                         if (rc) {
5595                                 cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc);
5596                                 break;
5597                         }
5598
5599                         if (!target_match) {
5600                                 cifs_dbg(FYI, "%s: skipping target\n", __func__);
5601                                 continue;
5602                         }
5603                 }
5604
5605                 if (tcon->ipc) {
5606                         scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", share);
5607                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
5608                 } else {
5609                         scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
5610                         rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
5611                         /* Only handle prefix paths of DFS link targets */
5612                         if (!rc && !isroot) {
5613                                 rc = update_super_prepath(tcon, prefix);
5614                                 break;
5615                         }
5616                 }
5617                 if (rc == -EREMOTE)
5618                         break;
5619         }
5620
5621         kfree(share);
5622         kfree(prefix);
5623
5624         if (!rc) {
5625                 if (it)
5626                         rc = dfs_cache_noreq_update_tgthint(tcon->dfs_path + 1, it);
5627                 else
5628                         rc = -ENOENT;
5629         }
5630         dfs_cache_free_tgts(&tl);
5631 out:
5632         kfree(tree);
5633         return rc;
5634 }
5635 #else
5636 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
5637 {
5638         const struct smb_version_operations *ops = tcon->ses->server->ops;
5639
5640         return ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
5641 }
5642 #endif