1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2011
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 */
8 #include <linux/fs.h>
9 #include <linux/net.h>
10 #include <linux/string.h>
11 #include <linux/sched/mm.h>
12 #include <linux/sched/signal.h>
13 #include <linux/list.h>
14 #include <linux/wait.h>
15 #include <linux/slab.h>
16 #include <linux/pagemap.h>
17 #include <linux/ctype.h>
18 #include <linux/utsname.h>
19 #include <linux/mempool.h>
20 #include <linux/delay.h>
21 #include <linux/completion.h>
22 #include <linux/kthread.h>
23 #include <linux/pagevec.h>
24 #include <linux/freezer.h>
25 #include <linux/namei.h>
26 #include <linux/uuid.h>
27 #include <linux/uaccess.h>
28 #include <asm/processor.h>
29 #include <linux/inet.h>
30 #include <linux/module.h>
31 #include <keys/user-type.h>
32 #include <net/ipv6.h>
33 #include <linux/parser.h>
34 #include <linux/bvec.h>
35 #include "cifspdu.h"
36 #include "cifsglob.h"
37 #include "cifsproto.h"
38 #include "cifs_unicode.h"
39 #include "cifs_debug.h"
40 #include "cifs_fs_sb.h"
41 #include "ntlmssp.h"
42 #include "nterr.h"
43 #include "rfc1002pdu.h"
44 #include "fscache.h"
45 #include "smb2proto.h"
46 #include "smbdirect.h"
47 #include "dns_resolve.h"
48 #ifdef CONFIG_CIFS_DFS_UPCALL
49 #include "dfs.h"
50 #include "dfs_cache.h"
51 #endif
52 #include "fs_context.h"
53 #include "cifs_swn.h"
54
55 extern mempool_t *cifs_req_poolp;
56 extern bool disable_legacy_dialects;
57
58 /* FIXME: should these be tunable? */
59 #define TLINK_ERROR_EXPIRE (1 * HZ)
60 #define TLINK_IDLE_EXPIRE (600 * HZ)
61
62 /* Drop the connection to not overload the server */
63 #define MAX_STATUS_IO_TIMEOUT 5
64
65 static int ip_connect(struct TCP_Server_Info *server);
66 static int generic_ip_connect(struct TCP_Server_Info *server);
67 static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
68 static void cifs_prune_tlinks(struct work_struct *work);
69
70 /*
71 * Resolve hostname and set ip addr in tcp ses. Useful for hostnames that may
72 * get their ip addresses changed at some point.
73 *
74 * This should be called with server->srv_mutex held.
75 */
reconn_set_ipaddr_from_hostname(struct TCP_Server_Info * server)76 static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
77 {
78 int rc;
79 int len;
80 char *unc;
81 struct sockaddr_storage ss;
82
83 if (!server->hostname)
84 return -EINVAL;
85
86 /* if server hostname isn't populated, there's nothing to do here */
87 if (server->hostname[0] == '\0')
88 return 0;
89
90 len = strlen(server->hostname) + 3;
91
92 unc = kmalloc(len, GFP_KERNEL);
93 if (!unc) {
94 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
95 return -ENOMEM;
96 }
97 scnprintf(unc, len, "\\\\%s", server->hostname);
98
99 spin_lock(&server->srv_lock);
100 ss = server->dstaddr;
101 spin_unlock(&server->srv_lock);
102
103 rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, NULL);
104 kfree(unc);
105
106 if (rc < 0) {
107 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
108 __func__, server->hostname, rc);
109 } else {
110 spin_lock(&server->srv_lock);
111 memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
112 spin_unlock(&server->srv_lock);
113 rc = 0;
114 }
115
116 return rc;
117 }
118
smb2_query_server_interfaces(struct work_struct * work)119 static void smb2_query_server_interfaces(struct work_struct *work)
120 {
121 int rc;
122 int xid;
123 struct cifs_tcon *tcon = container_of(work,
124 struct cifs_tcon,
125 query_interfaces.work);
126
127 /*
128 * query server network interfaces, in case they change
129 */
130 xid = get_xid();
131 rc = SMB3_request_interfaces(xid, tcon, false);
132 free_xid(xid);
133
134 if (rc) {
135 if (rc == -EOPNOTSUPP)
136 return;
137
138 cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
139 __func__, rc);
140 }
141
142 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
143 (SMB_INTERFACE_POLL_INTERVAL * HZ));
144 }
145
146 /*
147 * Update the tcpStatus for the server.
148 * This is used to signal the cifsd thread to call cifs_reconnect
149 * ONLY cifsd thread should call cifs_reconnect. For any other
150 * thread, use this function
151 *
152 * @server: the tcp ses for which reconnect is needed
153 * @all_channels: if this needs to be done for all channels
154 */
155 void
cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info * server,bool all_channels)156 cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
157 bool all_channels)
158 {
159 struct TCP_Server_Info *pserver;
160 struct cifs_ses *ses;
161 int i;
162
163 /* If server is a channel, select the primary channel */
164 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
165
166 /* if we need to signal just this channel */
167 if (!all_channels) {
168 spin_lock(&server->srv_lock);
169 if (server->tcpStatus != CifsExiting)
170 server->tcpStatus = CifsNeedReconnect;
171 spin_unlock(&server->srv_lock);
172 return;
173 }
174
175 spin_lock(&cifs_tcp_ses_lock);
176 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
177 spin_lock(&ses->chan_lock);
178 for (i = 0; i < ses->chan_count; i++) {
179 if (!ses->chans[i].server)
180 continue;
181
182 spin_lock(&ses->chans[i].server->srv_lock);
183 if (ses->chans[i].server->tcpStatus != CifsExiting)
184 ses->chans[i].server->tcpStatus = CifsNeedReconnect;
185 spin_unlock(&ses->chans[i].server->srv_lock);
186 }
187 spin_unlock(&ses->chan_lock);
188 }
189 spin_unlock(&cifs_tcp_ses_lock);
190 }
191
192 /*
193 * Mark all sessions and tcons for reconnect.
194 * IMPORTANT: make sure that this gets called only from
195 * cifsd thread. For any other thread, use
196 * cifs_signal_cifsd_for_reconnect
197 *
198 * @server: the tcp ses for which reconnect is needed
199 * @server needs to be previously set to CifsNeedReconnect.
200 * @mark_smb_session: whether even sessions need to be marked
201 */
202 void
cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info * server,bool mark_smb_session)203 cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
204 bool mark_smb_session)
205 {
206 struct TCP_Server_Info *pserver;
207 struct cifs_ses *ses, *nses;
208 struct cifs_tcon *tcon;
209
210 /*
211 * before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
212 * are not used until reconnected.
213 */
214 cifs_dbg(FYI, "%s: marking necessary sessions and tcons for reconnect\n", __func__);
215
216 /* If server is a channel, select the primary channel */
217 pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
218
219 /*
220 * if the server has been marked for termination, there is a
221 * chance that the remaining channels all need reconnect. To be
222 * on the safer side, mark the session and trees for reconnect
223 * for this scenario. This might cause a few redundant session
224 * setup and tree connect requests, but it is better than not doing
225 * a tree connect when needed, and all following requests failing
226 */
227 if (server->terminate) {
228 mark_smb_session = true;
229 server = pserver;
230 }
231
232 spin_lock(&cifs_tcp_ses_lock);
233 list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
234 /* check if iface is still active */
235 spin_lock(&ses->chan_lock);
236 if (cifs_ses_get_chan_index(ses, server) ==
237 CIFS_INVAL_CHAN_INDEX) {
238 spin_unlock(&ses->chan_lock);
239 continue;
240 }
241
242 if (!cifs_chan_is_iface_active(ses, server)) {
243 spin_unlock(&ses->chan_lock);
244 cifs_chan_update_iface(ses, server);
245 spin_lock(&ses->chan_lock);
246 }
247
248 if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server)) {
249 spin_unlock(&ses->chan_lock);
250 continue;
251 }
252
253 if (mark_smb_session)
254 CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses);
255 else
256 cifs_chan_set_need_reconnect(ses, server);
257
258 cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
259 __func__, ses->chans_need_reconnect);
260
261 /* If all channels need reconnect, then tcon needs reconnect */
262 if (!mark_smb_session && !CIFS_ALL_CHANS_NEED_RECONNECT(ses)) {
263 spin_unlock(&ses->chan_lock);
264 continue;
265 }
266 spin_unlock(&ses->chan_lock);
267
268 spin_lock(&ses->ses_lock);
269 ses->ses_status = SES_NEED_RECON;
270 spin_unlock(&ses->ses_lock);
271
272 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
273 tcon->need_reconnect = true;
274 spin_lock(&tcon->tc_lock);
275 tcon->status = TID_NEED_RECON;
276 spin_unlock(&tcon->tc_lock);
277
278 cancel_delayed_work(&tcon->query_interfaces);
279 }
280 if (ses->tcon_ipc) {
281 ses->tcon_ipc->need_reconnect = true;
282 spin_lock(&ses->tcon_ipc->tc_lock);
283 ses->tcon_ipc->status = TID_NEED_RECON;
284 spin_unlock(&ses->tcon_ipc->tc_lock);
285 }
286 }
287 spin_unlock(&cifs_tcp_ses_lock);
288 }
289
290 static void
cifs_abort_connection(struct TCP_Server_Info * server)291 cifs_abort_connection(struct TCP_Server_Info *server)
292 {
293 struct mid_q_entry *mid, *nmid;
294 struct list_head retry_list;
295
296 server->maxBuf = 0;
297 server->max_read = 0;
298
299 /* do not want to be sending data on a socket we are freeing */
300 cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
301 cifs_server_lock(server);
302 if (server->ssocket) {
303 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
304 server->ssocket->flags);
305 kernel_sock_shutdown(server->ssocket, SHUT_WR);
306 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
307 server->ssocket->flags);
308 sock_release(server->ssocket);
309 server->ssocket = NULL;
310 }
311 server->sequence_number = 0;
312 server->session_estab = false;
313 kfree_sensitive(server->session_key.response);
314 server->session_key.response = NULL;
315 server->session_key.len = 0;
316 server->lstrp = jiffies;
317
318 /* mark submitted MIDs for retry and issue callback */
319 INIT_LIST_HEAD(&retry_list);
320 cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
321 spin_lock(&server->mid_lock);
322 list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
323 kref_get(&mid->refcount);
324 if (mid->mid_state == MID_REQUEST_SUBMITTED)
325 mid->mid_state = MID_RETRY_NEEDED;
326 list_move(&mid->qhead, &retry_list);
327 mid->mid_flags |= MID_DELETED;
328 }
329 spin_unlock(&server->mid_lock);
330 cifs_server_unlock(server);
331
332 cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
333 list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
334 list_del_init(&mid->qhead);
335 mid->callback(mid);
336 release_mid(mid);
337 }
338
339 if (cifs_rdma_enabled(server)) {
340 cifs_server_lock(server);
341 smbd_destroy(server);
342 cifs_server_unlock(server);
343 }
344 }
345
cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info * server,int num_targets)346 static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
347 {
348 spin_lock(&server->srv_lock);
349 server->nr_targets = num_targets;
350 if (server->tcpStatus == CifsExiting) {
351 /* the demux thread will exit normally next time through the loop */
352 spin_unlock(&server->srv_lock);
353 wake_up(&server->response_q);
354 return false;
355 }
356
357 cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
358 trace_smb3_reconnect(server->CurrentMid, server->conn_id,
359 server->hostname);
360 server->tcpStatus = CifsNeedReconnect;
361
362 spin_unlock(&server->srv_lock);
363 return true;
364 }
365
366 /*
367 * cifs tcp session reconnection
368 *
369 * mark tcp session as reconnecting so temporarily locked
370 * mark all smb sessions as reconnecting for tcp session
371 * reconnect tcp session
372 * wake up waiters on reconnection? - (not needed currently)
373 *
374 * if mark_smb_session is passed as true, unconditionally mark
375 * the smb session (and tcon) for reconnect as well. This value
376 * doesn't really matter for non-multichannel scenario.
377 *
378 */
__cifs_reconnect(struct TCP_Server_Info * server,bool mark_smb_session)379 static int __cifs_reconnect(struct TCP_Server_Info *server,
380 bool mark_smb_session)
381 {
382 int rc = 0;
383
384 if (!cifs_tcp_ses_needs_reconnect(server, 1))
385 return 0;
386
387 cifs_mark_tcp_ses_conns_for_reconnect(server, mark_smb_session);
388
389 cifs_abort_connection(server);
390
391 do {
392 try_to_freeze();
393 cifs_server_lock(server);
394
395 if (!cifs_swn_set_server_dstaddr(server)) {
396 /* resolve the hostname again to make sure that IP address is up-to-date */
397 rc = reconn_set_ipaddr_from_hostname(server);
398 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
399 }
400
401 if (cifs_rdma_enabled(server))
402 rc = smbd_reconnect(server);
403 else
404 rc = generic_ip_connect(server);
405 if (rc) {
406 cifs_server_unlock(server);
407 cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
408 msleep(3000);
409 } else {
410 atomic_inc(&tcpSesReconnectCount);
411 set_credits(server, 1);
412 spin_lock(&server->srv_lock);
413 if (server->tcpStatus != CifsExiting)
414 server->tcpStatus = CifsNeedNegotiate;
415 spin_unlock(&server->srv_lock);
416 cifs_swn_reset_server_dstaddr(server);
417 cifs_server_unlock(server);
418 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
419 }
420 } while (server->tcpStatus == CifsNeedReconnect);
421
422 spin_lock(&server->srv_lock);
423 if (server->tcpStatus == CifsNeedNegotiate)
424 mod_delayed_work(cifsiod_wq, &server->echo, 0);
425 spin_unlock(&server->srv_lock);
426
427 wake_up(&server->response_q);
428 return rc;
429 }
430
431 #ifdef CONFIG_CIFS_DFS_UPCALL
__reconnect_target_unlocked(struct TCP_Server_Info * server,const char * target)432 static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
433 {
434 int rc;
435 char *hostname;
436
437 if (!cifs_swn_set_server_dstaddr(server)) {
438 if (server->hostname != target) {
439 hostname = extract_hostname(target);
440 if (!IS_ERR(hostname)) {
441 spin_lock(&server->srv_lock);
442 kfree(server->hostname);
443 server->hostname = hostname;
444 spin_unlock(&server->srv_lock);
445 } else {
446 cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
447 __func__, PTR_ERR(hostname));
448 cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
449 server->hostname);
450 }
451 }
452 /* resolve the hostname again to make sure that IP address is up-to-date. */
453 rc = reconn_set_ipaddr_from_hostname(server);
454 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
455 }
456 /* Reconnect the socket */
457 if (cifs_rdma_enabled(server))
458 rc = smbd_reconnect(server);
459 else
460 rc = generic_ip_connect(server);
461
462 return rc;
463 }
464
reconnect_target_unlocked(struct TCP_Server_Info * server,struct dfs_cache_tgt_list * tl,struct dfs_cache_tgt_iterator ** target_hint)465 static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
466 struct dfs_cache_tgt_iterator **target_hint)
467 {
468 int rc;
469 struct dfs_cache_tgt_iterator *tit;
470
471 *target_hint = NULL;
472
473 /* If dfs target list is empty, then reconnect to last server */
474 tit = dfs_cache_get_tgt_iterator(tl);
475 if (!tit)
476 return __reconnect_target_unlocked(server, server->hostname);
477
478 /* Otherwise, try every dfs target in @tl */
479 for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
480 rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
481 if (!rc) {
482 *target_hint = tit;
483 break;
484 }
485 }
486 return rc;
487 }
488
reconnect_dfs_server(struct TCP_Server_Info * server)489 static int reconnect_dfs_server(struct TCP_Server_Info *server)
490 {
491 struct dfs_cache_tgt_iterator *target_hint = NULL;
492
493 DFS_CACHE_TGT_LIST(tl);
494 int num_targets = 0;
495 int rc = 0;
496
497 /*
498 * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
499 *
500 * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
501 * targets (server->nr_targets). It's also possible that the cached referral was cleared
502 * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
503 * refreshing the referral, so, in this case, default it to 1.
504 */
505 mutex_lock(&server->refpath_lock);
506 if (!dfs_cache_noreq_find(server->leaf_fullpath + 1, NULL, &tl))
507 num_targets = dfs_cache_get_nr_tgts(&tl);
508 mutex_unlock(&server->refpath_lock);
509 if (!num_targets)
510 num_targets = 1;
511
512 if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
513 return 0;
514
515 /*
516 * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
517 * different server or share during failover. It could be improved by adding some logic to
518 * only do that in case it connects to a different server or share, though.
519 */
520 cifs_mark_tcp_ses_conns_for_reconnect(server, true);
521
522 cifs_abort_connection(server);
523
524 do {
525 try_to_freeze();
526 cifs_server_lock(server);
527
528 rc = reconnect_target_unlocked(server, &tl, &target_hint);
529 if (rc) {
530 /* Failed to reconnect socket */
531 cifs_server_unlock(server);
532 cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
533 msleep(3000);
534 continue;
535 }
536 /*
537 * Socket was created. Update tcp session status to CifsNeedNegotiate so that a
538 * process waiting for reconnect will know it needs to re-establish session and tcon
539 * through the reconnected target server.
540 */
541 atomic_inc(&tcpSesReconnectCount);
542 set_credits(server, 1);
543 spin_lock(&server->srv_lock);
544 if (server->tcpStatus != CifsExiting)
545 server->tcpStatus = CifsNeedNegotiate;
546 spin_unlock(&server->srv_lock);
547 cifs_swn_reset_server_dstaddr(server);
548 cifs_server_unlock(server);
549 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
550 } while (server->tcpStatus == CifsNeedReconnect);
551
552 mutex_lock(&server->refpath_lock);
553 dfs_cache_noreq_update_tgthint(server->leaf_fullpath + 1, target_hint);
554 mutex_unlock(&server->refpath_lock);
555 dfs_cache_free_tgts(&tl);
556
557 /* Need to set up echo worker again once connection has been established */
558 spin_lock(&server->srv_lock);
559 if (server->tcpStatus == CifsNeedNegotiate)
560 mod_delayed_work(cifsiod_wq, &server->echo, 0);
561 spin_unlock(&server->srv_lock);
562
563 wake_up(&server->response_q);
564 return rc;
565 }
566
cifs_reconnect(struct TCP_Server_Info * server,bool mark_smb_session)567 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
568 {
569 mutex_lock(&server->refpath_lock);
570 if (!server->leaf_fullpath) {
571 mutex_unlock(&server->refpath_lock);
572 return __cifs_reconnect(server, mark_smb_session);
573 }
574 mutex_unlock(&server->refpath_lock);
575
576 return reconnect_dfs_server(server);
577 }
578 #else
cifs_reconnect(struct TCP_Server_Info * server,bool mark_smb_session)579 int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
580 {
581 return __cifs_reconnect(server, mark_smb_session);
582 }
583 #endif
584
585 static void
cifs_echo_request(struct work_struct * work)586 cifs_echo_request(struct work_struct *work)
587 {
588 int rc;
589 struct TCP_Server_Info *server = container_of(work,
590 struct TCP_Server_Info, echo.work);
591
592 /*
593 * We cannot send an echo if it is disabled.
594 * Also, no need to ping if we got a response recently.
595 */
596
597 if (server->tcpStatus == CifsNeedReconnect ||
598 server->tcpStatus == CifsExiting ||
599 server->tcpStatus == CifsNew ||
600 (server->ops->can_echo && !server->ops->can_echo(server)) ||
601 time_before(jiffies, server->lstrp + server->echo_interval - HZ))
602 goto requeue_echo;
603
604 rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
605 cifs_server_dbg(FYI, "send echo request: rc = %d\n", rc);
606
607 /* Check witness registrations */
608 cifs_swn_check();
609
610 requeue_echo:
611 queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
612 }
613
614 static bool
allocate_buffers(struct TCP_Server_Info * server)615 allocate_buffers(struct TCP_Server_Info *server)
616 {
617 if (!server->bigbuf) {
618 server->bigbuf = (char *)cifs_buf_get();
619 if (!server->bigbuf) {
620 cifs_server_dbg(VFS, "No memory for large SMB response\n");
621 msleep(3000);
622 /* retry will check if exiting */
623 return false;
624 }
625 } else if (server->large_buf) {
626 /* we are reusing a dirty large buf, clear its start */
627 memset(server->bigbuf, 0, HEADER_SIZE(server));
628 }
629
630 if (!server->smallbuf) {
631 server->smallbuf = (char *)cifs_small_buf_get();
632 if (!server->smallbuf) {
633 cifs_server_dbg(VFS, "No memory for SMB response\n");
634 msleep(1000);
635 /* retry will check if exiting */
636 return false;
637 }
638 /* beginning of smb buffer is cleared in our buf_get */
639 } else {
640 /* if existing small buf clear beginning */
641 memset(server->smallbuf, 0, HEADER_SIZE(server));
642 }
643
644 return true;
645 }
646
647 static bool
server_unresponsive(struct TCP_Server_Info * server)648 server_unresponsive(struct TCP_Server_Info *server)
649 {
650 /*
651 * We need to wait 3 echo intervals to make sure we handle such
652 * situations right:
653 * 1s client sends a normal SMB request
654 * 2s client gets a response
655 * 30s echo workqueue job pops, and decides we got a response recently
656 * and don't need to send another
657 * ...
658 * 65s kernel_recvmsg times out, and we see that we haven't gotten
659 * a response in >60s.
660 */
661 spin_lock(&server->srv_lock);
662 if ((server->tcpStatus == CifsGood ||
663 server->tcpStatus == CifsNeedNegotiate) &&
664 (!server->ops->can_echo || server->ops->can_echo(server)) &&
665 time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
666 spin_unlock(&server->srv_lock);
667 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
668 (3 * server->echo_interval) / HZ);
669 cifs_reconnect(server, false);
670 return true;
671 }
672 spin_unlock(&server->srv_lock);
673
674 return false;
675 }
676
677 static inline bool
zero_credits(struct TCP_Server_Info * server)678 zero_credits(struct TCP_Server_Info *server)
679 {
680 int val;
681
682 spin_lock(&server->req_lock);
683 val = server->credits + server->echo_credits + server->oplock_credits;
684 if (server->in_flight == 0 && val == 0) {
685 spin_unlock(&server->req_lock);
686 return true;
687 }
688 spin_unlock(&server->req_lock);
689 return false;
690 }
691
692 static int
cifs_readv_from_socket(struct TCP_Server_Info * server,struct msghdr * smb_msg)693 cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
694 {
695 int length = 0;
696 int total_read;
697
698 for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
699 try_to_freeze();
700
701 /* reconnect if no credits and no requests in flight */
702 if (zero_credits(server)) {
703 cifs_reconnect(server, false);
704 return -ECONNABORTED;
705 }
706
707 if (server_unresponsive(server))
708 return -ECONNABORTED;
709 if (cifs_rdma_enabled(server) && server->smbd_conn)
710 length = smbd_recv(server->smbd_conn, smb_msg);
711 else
712 length = sock_recvmsg(server->ssocket, smb_msg, 0);
713
714 spin_lock(&server->srv_lock);
715 if (server->tcpStatus == CifsExiting) {
716 spin_unlock(&server->srv_lock);
717 return -ESHUTDOWN;
718 }
719
720 if (server->tcpStatus == CifsNeedReconnect) {
721 spin_unlock(&server->srv_lock);
722 cifs_reconnect(server, false);
723 return -ECONNABORTED;
724 }
725 spin_unlock(&server->srv_lock);
726
727 if (length == -ERESTARTSYS ||
728 length == -EAGAIN ||
729 length == -EINTR) {
730 /*
731 * Minimum sleep to prevent looping, allowing socket
732 * to clear and app threads to set tcpStatus
733 * CifsNeedReconnect if server hung.
734 */
735 usleep_range(1000, 2000);
736 length = 0;
737 continue;
738 }
739
740 if (length <= 0) {
741 cifs_dbg(FYI, "Received no data or error: %d\n", length);
742 cifs_reconnect(server, false);
743 return -ECONNABORTED;
744 }
745 }
746 return total_read;
747 }
748
749 int
cifs_read_from_socket(struct TCP_Server_Info * server,char * buf,unsigned int to_read)750 cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
751 unsigned int to_read)
752 {
753 struct msghdr smb_msg = {};
754 struct kvec iov = {.iov_base = buf, .iov_len = to_read};
755
756 iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
757
758 return cifs_readv_from_socket(server, &smb_msg);
759 }
760
761 ssize_t
cifs_discard_from_socket(struct TCP_Server_Info * server,size_t to_read)762 cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
763 {
764 struct msghdr smb_msg = {};
765
766 /*
767 * iov_iter_discard already sets smb_msg.type and count and iov_offset
768 * and cifs_readv_from_socket sets msg_control and msg_controllen
769 * so little to initialize in struct msghdr
770 */
771 iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
772
773 return cifs_readv_from_socket(server, &smb_msg);
774 }
775
776 int
cifs_read_page_from_socket(struct TCP_Server_Info * server,struct page * page,unsigned int page_offset,unsigned int to_read)777 cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
778 unsigned int page_offset, unsigned int to_read)
779 {
780 struct msghdr smb_msg = {};
781 struct bio_vec bv;
782
783 bvec_set_page(&bv, page, to_read, page_offset);
784 iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
785 return cifs_readv_from_socket(server, &smb_msg);
786 }
787
788 int
cifs_read_iter_from_socket(struct TCP_Server_Info * server,struct iov_iter * iter,unsigned int to_read)789 cifs_read_iter_from_socket(struct TCP_Server_Info *server, struct iov_iter *iter,
790 unsigned int to_read)
791 {
792 struct msghdr smb_msg = { .msg_iter = *iter };
793 int ret;
794
795 iov_iter_truncate(&smb_msg.msg_iter, to_read);
796 ret = cifs_readv_from_socket(server, &smb_msg);
797 if (ret > 0)
798 iov_iter_advance(iter, ret);
799 return ret;
800 }
801
802 static bool
is_smb_response(struct TCP_Server_Info * server,unsigned char type)803 is_smb_response(struct TCP_Server_Info *server, unsigned char type)
804 {
805 /*
806 * The first byte big endian of the length field,
807 * is actually not part of the length but the type
808 * with the most common, zero, as regular data.
809 */
810 switch (type) {
811 case RFC1002_SESSION_MESSAGE:
812 /* Regular SMB response */
813 return true;
814 case RFC1002_SESSION_KEEP_ALIVE:
815 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
816 break;
817 case RFC1002_POSITIVE_SESSION_RESPONSE:
818 cifs_dbg(FYI, "RFC 1002 positive session response\n");
819 break;
820 case RFC1002_NEGATIVE_SESSION_RESPONSE:
821 /*
822 * We get this from Windows 98 instead of an error on
823 * SMB negprot response.
824 */
825 cifs_dbg(FYI, "RFC 1002 negative session response\n");
826 /* give server a second to clean up */
827 msleep(1000);
828 /*
829 * Always try 445 first on reconnect since we get NACK
830 * on some if we ever connected to port 139 (the NACK
831 * is since we do not begin with RFC1001 session
832 * initialize frame).
833 */
834 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
835 cifs_reconnect(server, true);
836 break;
837 default:
838 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
839 cifs_reconnect(server, true);
840 }
841
842 return false;
843 }
844
845 void
dequeue_mid(struct mid_q_entry * mid,bool malformed)846 dequeue_mid(struct mid_q_entry *mid, bool malformed)
847 {
848 #ifdef CONFIG_CIFS_STATS2
849 mid->when_received = jiffies;
850 #endif
851 spin_lock(&mid->server->mid_lock);
852 if (!malformed)
853 mid->mid_state = MID_RESPONSE_RECEIVED;
854 else
855 mid->mid_state = MID_RESPONSE_MALFORMED;
856 /*
857 * Trying to handle/dequeue a mid after the send_recv()
858 * function has finished processing it is a bug.
859 */
860 if (mid->mid_flags & MID_DELETED) {
861 spin_unlock(&mid->server->mid_lock);
862 pr_warn_once("trying to dequeue a deleted mid\n");
863 } else {
864 list_del_init(&mid->qhead);
865 mid->mid_flags |= MID_DELETED;
866 spin_unlock(&mid->server->mid_lock);
867 }
868 }
869
870 static unsigned int
smb2_get_credits_from_hdr(char * buffer,struct TCP_Server_Info * server)871 smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
872 {
873 struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
874
875 /*
876 * SMB1 does not use credits.
877 */
878 if (is_smb1(server))
879 return 0;
880
881 return le16_to_cpu(shdr->CreditRequest);
882 }
883
884 static void
handle_mid(struct mid_q_entry * mid,struct TCP_Server_Info * server,char * buf,int malformed)885 handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
886 char *buf, int malformed)
887 {
888 if (server->ops->check_trans2 &&
889 server->ops->check_trans2(mid, server, buf, malformed))
890 return;
891 mid->credits_received = smb2_get_credits_from_hdr(buf, server);
892 mid->resp_buf = buf;
893 mid->large_buf = server->large_buf;
894 /* Was previous buf put in mpx struct for multi-rsp? */
895 if (!mid->multiRsp) {
896 /* smb buffer will be freed by user thread */
897 if (server->large_buf)
898 server->bigbuf = NULL;
899 else
900 server->smallbuf = NULL;
901 }
902 dequeue_mid(mid, malformed);
903 }
904
905 int
cifs_enable_signing(struct TCP_Server_Info * server,bool mnt_sign_required)906 cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
907 {
908 bool srv_sign_required = server->sec_mode & server->vals->signing_required;
909 bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
910 bool mnt_sign_enabled;
911
912 /*
913 * Is signing required by mnt options? If not then check
914 * global_secflags to see if it is there.
915 */
916 if (!mnt_sign_required)
917 mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
918 CIFSSEC_MUST_SIGN);
919
920 /*
921 * If signing is required then it's automatically enabled too,
922 * otherwise, check to see if the secflags allow it.
923 */
924 mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
925 (global_secflags & CIFSSEC_MAY_SIGN);
926
927 /* If server requires signing, does client allow it? */
928 if (srv_sign_required) {
929 if (!mnt_sign_enabled) {
930 cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
931 return -EOPNOTSUPP;
932 }
933 server->sign = true;
934 }
935
936 /* If client requires signing, does server allow it? */
937 if (mnt_sign_required) {
938 if (!srv_sign_enabled) {
939 cifs_dbg(VFS, "Server does not support signing!\n");
940 return -EOPNOTSUPP;
941 }
942 server->sign = true;
943 }
944
945 if (cifs_rdma_enabled(server) && server->sign)
946 cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
947
948 return 0;
949 }
950
951 static noinline_for_stack void
clean_demultiplex_info(struct TCP_Server_Info * server)952 clean_demultiplex_info(struct TCP_Server_Info *server)
953 {
954 int length;
955
956 /* take it off the list, if it's not already */
957 spin_lock(&server->srv_lock);
958 list_del_init(&server->tcp_ses_list);
959 spin_unlock(&server->srv_lock);
960
961 cancel_delayed_work_sync(&server->echo);
962
963 spin_lock(&server->srv_lock);
964 server->tcpStatus = CifsExiting;
965 spin_unlock(&server->srv_lock);
966 wake_up_all(&server->response_q);
967
968 /* check if we have blocked requests that need to free */
969 spin_lock(&server->req_lock);
970 if (server->credits <= 0)
971 server->credits = 1;
972 spin_unlock(&server->req_lock);
973 /*
974 * Although there should not be any requests blocked on this queue it
975 * can not hurt to be paranoid and try to wake up requests that may
976 * haven been blocked when more than 50 at time were on the wire to the
977 * same server - they now will see the session is in exit state and get
978 * out of SendReceive.
979 */
980 wake_up_all(&server->request_q);
981 /* give those requests time to exit */
982 msleep(125);
983 if (cifs_rdma_enabled(server))
984 smbd_destroy(server);
985 if (server->ssocket) {
986 sock_release(server->ssocket);
987 server->ssocket = NULL;
988 }
989
990 if (!list_empty(&server->pending_mid_q)) {
991 struct list_head dispose_list;
992 struct mid_q_entry *mid_entry;
993 struct list_head *tmp, *tmp2;
994
995 INIT_LIST_HEAD(&dispose_list);
996 spin_lock(&server->mid_lock);
997 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
998 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
999 cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
1000 kref_get(&mid_entry->refcount);
1001 mid_entry->mid_state = MID_SHUTDOWN;
1002 list_move(&mid_entry->qhead, &dispose_list);
1003 mid_entry->mid_flags |= MID_DELETED;
1004 }
1005 spin_unlock(&server->mid_lock);
1006
1007 /* now walk dispose list and issue callbacks */
1008 list_for_each_safe(tmp, tmp2, &dispose_list) {
1009 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
1010 cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
1011 list_del_init(&mid_entry->qhead);
1012 mid_entry->callback(mid_entry);
1013 release_mid(mid_entry);
1014 }
1015 /* 1/8th of sec is more than enough time for them to exit */
1016 msleep(125);
1017 }
1018
1019 if (!list_empty(&server->pending_mid_q)) {
1020 /*
1021 * mpx threads have not exited yet give them at least the smb
1022 * send timeout time for long ops.
1023 *
1024 * Due to delays on oplock break requests, we need to wait at
1025 * least 45 seconds before giving up on a request getting a
1026 * response and going ahead and killing cifsd.
1027 */
1028 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
1029 msleep(46000);
1030 /*
1031 * If threads still have not exited they are probably never
1032 * coming home not much else we can do but free the memory.
1033 */
1034 }
1035
1036 kfree(server->leaf_fullpath);
1037 kfree(server);
1038
1039 length = atomic_dec_return(&tcpSesAllocCount);
1040 if (length > 0)
1041 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1042 }
1043
1044 static int
standard_receive3(struct TCP_Server_Info * server,struct mid_q_entry * mid)1045 standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1046 {
1047 int length;
1048 char *buf = server->smallbuf;
1049 unsigned int pdu_length = server->pdu_size;
1050
1051 /* make sure this will fit in a large buffer */
1052 if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1053 HEADER_PREAMBLE_SIZE(server)) {
1054 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1055 cifs_reconnect(server, true);
1056 return -ECONNABORTED;
1057 }
1058
1059 /* switch to large buffer if too big for a small one */
1060 if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1061 server->large_buf = true;
1062 memcpy(server->bigbuf, buf, server->total_read);
1063 buf = server->bigbuf;
1064 }
1065
1066 /* now read the rest */
1067 length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1068 pdu_length - MID_HEADER_SIZE(server));
1069
1070 if (length < 0)
1071 return length;
1072 server->total_read += length;
1073
1074 dump_smb(buf, server->total_read);
1075
1076 return cifs_handle_standard(server, mid);
1077 }
1078
1079 int
cifs_handle_standard(struct TCP_Server_Info * server,struct mid_q_entry * mid)1080 cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1081 {
1082 char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1083 int rc;
1084
1085 /*
1086 * We know that we received enough to get to the MID as we
1087 * checked the pdu_length earlier. Now check to see
1088 * if the rest of the header is OK.
1089 *
1090 * 48 bytes is enough to display the header and a little bit
1091 * into the payload for debugging purposes.
1092 */
1093 rc = server->ops->check_message(buf, server->total_read, server);
1094 if (rc)
1095 cifs_dump_mem("Bad SMB: ", buf,
1096 min_t(unsigned int, server->total_read, 48));
1097
1098 if (server->ops->is_session_expired &&
1099 server->ops->is_session_expired(buf)) {
1100 cifs_reconnect(server, true);
1101 return -1;
1102 }
1103
1104 if (server->ops->is_status_pending &&
1105 server->ops->is_status_pending(buf, server))
1106 return -1;
1107
1108 if (!mid)
1109 return rc;
1110
1111 handle_mid(mid, server, buf, rc);
1112 return 0;
1113 }
1114
1115 static void
smb2_add_credits_from_hdr(char * buffer,struct TCP_Server_Info * server)1116 smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1117 {
1118 struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
1119 int scredits, in_flight;
1120
1121 /*
1122 * SMB1 does not use credits.
1123 */
1124 if (is_smb1(server))
1125 return;
1126
1127 if (shdr->CreditRequest) {
1128 spin_lock(&server->req_lock);
1129 server->credits += le16_to_cpu(shdr->CreditRequest);
1130 scredits = server->credits;
1131 in_flight = server->in_flight;
1132 spin_unlock(&server->req_lock);
1133 wake_up(&server->request_q);
1134
1135 trace_smb3_hdr_credits(server->CurrentMid,
1136 server->conn_id, server->hostname, scredits,
1137 le16_to_cpu(shdr->CreditRequest), in_flight);
1138 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
1139 __func__, le16_to_cpu(shdr->CreditRequest),
1140 scredits);
1141 }
1142 }
1143
1144
1145 static int
cifs_demultiplex_thread(void * p)1146 cifs_demultiplex_thread(void *p)
1147 {
1148 int i, num_mids, length;
1149 struct TCP_Server_Info *server = p;
1150 unsigned int pdu_length;
1151 unsigned int next_offset;
1152 char *buf = NULL;
1153 struct task_struct *task_to_wake = NULL;
1154 struct mid_q_entry *mids[MAX_COMPOUND];
1155 char *bufs[MAX_COMPOUND];
1156 unsigned int noreclaim_flag, num_io_timeout = 0;
1157 bool pending_reconnect = false;
1158
1159 noreclaim_flag = memalloc_noreclaim_save();
1160 cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1161
1162 length = atomic_inc_return(&tcpSesAllocCount);
1163 if (length > 1)
1164 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1165
1166 set_freezable();
1167 allow_kernel_signal(SIGKILL);
1168 while (server->tcpStatus != CifsExiting) {
1169 if (try_to_freeze())
1170 continue;
1171
1172 if (!allocate_buffers(server))
1173 continue;
1174
1175 server->large_buf = false;
1176 buf = server->smallbuf;
1177 pdu_length = 4; /* enough to get RFC1001 header */
1178
1179 length = cifs_read_from_socket(server, buf, pdu_length);
1180 if (length < 0)
1181 continue;
1182
1183 if (is_smb1(server))
1184 server->total_read = length;
1185 else
1186 server->total_read = 0;
1187
1188 /*
1189 * The right amount was read from socket - 4 bytes,
1190 * so we can now interpret the length field.
1191 */
1192 pdu_length = get_rfc1002_length(buf);
1193
1194 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1195 if (!is_smb_response(server, buf[0]))
1196 continue;
1197
1198 pending_reconnect = false;
1199 next_pdu:
1200 server->pdu_size = pdu_length;
1201
1202 /* make sure we have enough to get to the MID */
1203 if (server->pdu_size < MID_HEADER_SIZE(server)) {
1204 cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1205 server->pdu_size);
1206 cifs_reconnect(server, true);
1207 continue;
1208 }
1209
1210 /* read down to the MID */
1211 length = cifs_read_from_socket(server,
1212 buf + HEADER_PREAMBLE_SIZE(server),
1213 MID_HEADER_SIZE(server));
1214 if (length < 0)
1215 continue;
1216 server->total_read += length;
1217
1218 if (server->ops->next_header) {
1219 if (server->ops->next_header(server, buf, &next_offset)) {
1220 cifs_dbg(VFS, "%s: malformed response (next_offset=%u)\n",
1221 __func__, next_offset);
1222 cifs_reconnect(server, true);
1223 continue;
1224 }
1225 if (next_offset)
1226 server->pdu_size = next_offset;
1227 }
1228
1229 memset(mids, 0, sizeof(mids));
1230 memset(bufs, 0, sizeof(bufs));
1231 num_mids = 0;
1232
1233 if (server->ops->is_transform_hdr &&
1234 server->ops->receive_transform &&
1235 server->ops->is_transform_hdr(buf)) {
1236 length = server->ops->receive_transform(server,
1237 mids,
1238 bufs,
1239 &num_mids);
1240 } else {
1241 mids[0] = server->ops->find_mid(server, buf);
1242 bufs[0] = buf;
1243 num_mids = 1;
1244
1245 if (!mids[0] || !mids[0]->receive)
1246 length = standard_receive3(server, mids[0]);
1247 else
1248 length = mids[0]->receive(server, mids[0]);
1249 }
1250
1251 if (length < 0) {
1252 for (i = 0; i < num_mids; i++)
1253 if (mids[i])
1254 release_mid(mids[i]);
1255 continue;
1256 }
1257
1258 if (server->ops->is_status_io_timeout &&
1259 server->ops->is_status_io_timeout(buf)) {
1260 num_io_timeout++;
1261 if (num_io_timeout > MAX_STATUS_IO_TIMEOUT) {
1262 cifs_server_dbg(VFS,
1263 "Number of request timeouts exceeded %d. Reconnecting",
1264 MAX_STATUS_IO_TIMEOUT);
1265
1266 pending_reconnect = true;
1267 num_io_timeout = 0;
1268 }
1269 }
1270
1271 server->lstrp = jiffies;
1272
1273 for (i = 0; i < num_mids; i++) {
1274 if (mids[i] != NULL) {
1275 mids[i]->resp_buf_size = server->pdu_size;
1276
1277 if (bufs[i] != NULL) {
1278 if (server->ops->is_network_name_deleted &&
1279 server->ops->is_network_name_deleted(bufs[i],
1280 server)) {
1281 cifs_server_dbg(FYI,
1282 "Share deleted. Reconnect needed");
1283 }
1284 }
1285
1286 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1287 mids[i]->callback(mids[i]);
1288
1289 release_mid(mids[i]);
1290 } else if (server->ops->is_oplock_break &&
1291 server->ops->is_oplock_break(bufs[i],
1292 server)) {
1293 smb2_add_credits_from_hdr(bufs[i], server);
1294 cifs_dbg(FYI, "Received oplock break\n");
1295 } else {
1296 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1297 atomic_read(&mid_count));
1298 cifs_dump_mem("Received Data is: ", bufs[i],
1299 HEADER_SIZE(server));
1300 smb2_add_credits_from_hdr(bufs[i], server);
1301 #ifdef CONFIG_CIFS_DEBUG2
1302 if (server->ops->dump_detail)
1303 server->ops->dump_detail(bufs[i],
1304 server);
1305 cifs_dump_mids(server);
1306 #endif /* CIFS_DEBUG2 */
1307 }
1308 }
1309
1310 if (pdu_length > server->pdu_size) {
1311 if (!allocate_buffers(server))
1312 continue;
1313 pdu_length -= server->pdu_size;
1314 server->total_read = 0;
1315 server->large_buf = false;
1316 buf = server->smallbuf;
1317 goto next_pdu;
1318 }
1319
1320 /* do this reconnect at the very end after processing all MIDs */
1321 if (pending_reconnect)
1322 cifs_reconnect(server, true);
1323
1324 } /* end while !EXITING */
1325
1326 /* buffer usually freed in free_mid - need to free it here on exit */
1327 cifs_buf_release(server->bigbuf);
1328 if (server->smallbuf) /* no sense logging a debug message if NULL */
1329 cifs_small_buf_release(server->smallbuf);
1330
1331 task_to_wake = xchg(&server->tsk, NULL);
1332 clean_demultiplex_info(server);
1333
1334 /* if server->tsk was NULL then wait for a signal before exiting */
1335 if (!task_to_wake) {
1336 set_current_state(TASK_INTERRUPTIBLE);
1337 while (!signal_pending(current)) {
1338 schedule();
1339 set_current_state(TASK_INTERRUPTIBLE);
1340 }
1341 set_current_state(TASK_RUNNING);
1342 }
1343
1344 memalloc_noreclaim_restore(noreclaim_flag);
1345 module_put_and_kthread_exit(0);
1346 }
1347
1348 int
cifs_ipaddr_cmp(struct sockaddr * srcaddr,struct sockaddr * rhs)1349 cifs_ipaddr_cmp(struct sockaddr *srcaddr, struct sockaddr *rhs)
1350 {
1351 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1352 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1353 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1354 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1355
1356 switch (srcaddr->sa_family) {
1357 case AF_UNSPEC:
1358 switch (rhs->sa_family) {
1359 case AF_UNSPEC:
1360 return 0;
1361 case AF_INET:
1362 case AF_INET6:
1363 return 1;
1364 default:
1365 return -1;
1366 }
1367 case AF_INET: {
1368 switch (rhs->sa_family) {
1369 case AF_UNSPEC:
1370 return -1;
1371 case AF_INET:
1372 return memcmp(saddr4, vaddr4,
1373 sizeof(struct sockaddr_in));
1374 case AF_INET6:
1375 return 1;
1376 default:
1377 return -1;
1378 }
1379 }
1380 case AF_INET6: {
1381 switch (rhs->sa_family) {
1382 case AF_UNSPEC:
1383 case AF_INET:
1384 return -1;
1385 case AF_INET6:
1386 return memcmp(saddr6,
1387 vaddr6,
1388 sizeof(struct sockaddr_in6));
1389 default:
1390 return -1;
1391 }
1392 }
1393 default:
1394 return -1; /* don't expect to be here */
1395 }
1396 }
1397
1398 /*
1399 * Returns true if srcaddr isn't specified and rhs isn't specified, or
1400 * if srcaddr is specified and matches the IP address of the rhs argument
1401 */
1402 bool
cifs_match_ipaddr(struct sockaddr * srcaddr,struct sockaddr * rhs)1403 cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1404 {
1405 switch (srcaddr->sa_family) {
1406 case AF_UNSPEC:
1407 return (rhs->sa_family == AF_UNSPEC);
1408 case AF_INET: {
1409 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1410 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1411
1412 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1413 }
1414 case AF_INET6: {
1415 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1416 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1417
1418 return (ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr)
1419 && saddr6->sin6_scope_id == vaddr6->sin6_scope_id);
1420 }
1421 default:
1422 WARN_ON(1);
1423 return false; /* don't expect to be here */
1424 }
1425 }
1426
1427 /*
1428 * If no port is specified in addr structure, we try to match with 445 port
1429 * and if it fails - with 139 ports. It should be called only if address
1430 * families of server and addr are equal.
1431 */
1432 static bool
match_port(struct TCP_Server_Info * server,struct sockaddr * addr)1433 match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1434 {
1435 __be16 port, *sport;
1436
1437 /* SMBDirect manages its own ports, don't match it here */
1438 if (server->rdma)
1439 return true;
1440
1441 switch (addr->sa_family) {
1442 case AF_INET:
1443 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1444 port = ((struct sockaddr_in *) addr)->sin_port;
1445 break;
1446 case AF_INET6:
1447 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1448 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1449 break;
1450 default:
1451 WARN_ON(1);
1452 return false;
1453 }
1454
1455 if (!port) {
1456 port = htons(CIFS_PORT);
1457 if (port == *sport)
1458 return true;
1459
1460 port = htons(RFC1001_PORT);
1461 }
1462
1463 return port == *sport;
1464 }
1465
match_server_address(struct TCP_Server_Info * server,struct sockaddr * addr)1466 static bool match_server_address(struct TCP_Server_Info *server, struct sockaddr *addr)
1467 {
1468 if (!cifs_match_ipaddr(addr, (struct sockaddr *)&server->dstaddr))
1469 return false;
1470
1471 return true;
1472 }
1473
1474 static bool
match_security(struct TCP_Server_Info * server,struct smb3_fs_context * ctx)1475 match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1476 {
1477 /*
1478 * The select_sectype function should either return the ctx->sectype
1479 * that was specified, or "Unspecified" if that sectype was not
1480 * compatible with the given NEGOTIATE request.
1481 */
1482 if (server->ops->select_sectype(server, ctx->sectype)
1483 == Unspecified)
1484 return false;
1485
1486 /*
1487 * Now check if signing mode is acceptable. No need to check
1488 * global_secflags at this point since if MUST_SIGN is set then
1489 * the server->sign had better be too.
1490 */
1491 if (ctx->sign && !server->sign)
1492 return false;
1493
1494 return true;
1495 }
1496
1497 /* this function must be called with srv_lock held */
match_server(struct TCP_Server_Info * server,struct smb3_fs_context * ctx,bool match_super)1498 static int match_server(struct TCP_Server_Info *server,
1499 struct smb3_fs_context *ctx,
1500 bool match_super)
1501 {
1502 struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1503
1504 lockdep_assert_held(&server->srv_lock);
1505
1506 if (ctx->nosharesock)
1507 return 0;
1508
1509 /* this server does not share socket */
1510 if (server->nosharesock)
1511 return 0;
1512
1513 /* If multidialect negotiation see if existing sessions match one */
1514 if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1515 if (server->vals->protocol_id < SMB30_PROT_ID)
1516 return 0;
1517 } else if (strcmp(ctx->vals->version_string,
1518 SMBDEFAULT_VERSION_STRING) == 0) {
1519 if (server->vals->protocol_id < SMB21_PROT_ID)
1520 return 0;
1521 } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1522 return 0;
1523
1524 if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1525 return 0;
1526
1527 if (!cifs_match_ipaddr((struct sockaddr *)&ctx->srcaddr,
1528 (struct sockaddr *)&server->srcaddr))
1529 return 0;
1530 /*
1531 * When matching cifs.ko superblocks (@match_super == true), we can't
1532 * really match either @server->leaf_fullpath or @server->dstaddr
1533 * directly since this @server might belong to a completely different
1534 * server -- in case of domain-based DFS referrals or DFS links -- as
1535 * provided earlier by mount(2) through 'source' and 'ip' options.
1536 *
1537 * Otherwise, match the DFS referral in @server->leaf_fullpath or the
1538 * destination address in @server->dstaddr.
1539 *
1540 * When using 'nodfs' mount option, we avoid sharing it with DFS
1541 * connections as they might failover.
1542 */
1543 if (!match_super) {
1544 if (!ctx->nodfs) {
1545 if (server->leaf_fullpath) {
1546 if (!ctx->leaf_fullpath ||
1547 strcasecmp(server->leaf_fullpath,
1548 ctx->leaf_fullpath))
1549 return 0;
1550 } else if (ctx->leaf_fullpath) {
1551 return 0;
1552 }
1553 } else if (server->leaf_fullpath) {
1554 return 0;
1555 }
1556 }
1557
1558 /*
1559 * Match for a regular connection (address/hostname/port) which has no
1560 * DFS referrals set.
1561 */
1562 if (!server->leaf_fullpath &&
1563 (strcasecmp(server->hostname, ctx->server_hostname) ||
1564 !match_server_address(server, addr) ||
1565 !match_port(server, addr)))
1566 return 0;
1567
1568 if (!match_security(server, ctx))
1569 return 0;
1570
1571 if (server->echo_interval != ctx->echo_interval * HZ)
1572 return 0;
1573
1574 if (server->rdma != ctx->rdma)
1575 return 0;
1576
1577 if (server->ignore_signature != ctx->ignore_signature)
1578 return 0;
1579
1580 if (server->min_offload != ctx->min_offload)
1581 return 0;
1582
1583 if (server->retrans != ctx->retrans)
1584 return 0;
1585
1586 return 1;
1587 }
1588
1589 struct TCP_Server_Info *
cifs_find_tcp_session(struct smb3_fs_context * ctx)1590 cifs_find_tcp_session(struct smb3_fs_context *ctx)
1591 {
1592 struct TCP_Server_Info *server;
1593
1594 spin_lock(&cifs_tcp_ses_lock);
1595 list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1596 spin_lock(&server->srv_lock);
1597 /*
1598 * Skip ses channels since they're only handled in lower layers
1599 * (e.g. cifs_send_recv).
1600 */
1601 if (SERVER_IS_CHAN(server) ||
1602 !match_server(server, ctx, false)) {
1603 spin_unlock(&server->srv_lock);
1604 continue;
1605 }
1606 spin_unlock(&server->srv_lock);
1607
1608 ++server->srv_count;
1609 spin_unlock(&cifs_tcp_ses_lock);
1610 cifs_dbg(FYI, "Existing tcp session with server found\n");
1611 return server;
1612 }
1613 spin_unlock(&cifs_tcp_ses_lock);
1614 return NULL;
1615 }
1616
1617 void
cifs_put_tcp_session(struct TCP_Server_Info * server,int from_reconnect)1618 cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1619 {
1620 struct task_struct *task;
1621
1622 spin_lock(&cifs_tcp_ses_lock);
1623 if (--server->srv_count > 0) {
1624 spin_unlock(&cifs_tcp_ses_lock);
1625 return;
1626 }
1627
1628 /* srv_count can never go negative */
1629 WARN_ON(server->srv_count < 0);
1630
1631 put_net(cifs_net_ns(server));
1632
1633 list_del_init(&server->tcp_ses_list);
1634 spin_unlock(&cifs_tcp_ses_lock);
1635
1636 cancel_delayed_work_sync(&server->echo);
1637
1638 if (from_reconnect)
1639 /*
1640 * Avoid deadlock here: reconnect work calls
1641 * cifs_put_tcp_session() at its end. Need to be sure
1642 * that reconnect work does nothing with server pointer after
1643 * that step.
1644 */
1645 cancel_delayed_work(&server->reconnect);
1646 else
1647 cancel_delayed_work_sync(&server->reconnect);
1648
1649 /* For secondary channels, we pick up ref-count on the primary server */
1650 if (SERVER_IS_CHAN(server))
1651 cifs_put_tcp_session(server->primary_server, from_reconnect);
1652
1653 spin_lock(&server->srv_lock);
1654 server->tcpStatus = CifsExiting;
1655 spin_unlock(&server->srv_lock);
1656
1657 cifs_crypto_secmech_release(server);
1658
1659 kfree_sensitive(server->session_key.response);
1660 server->session_key.response = NULL;
1661 server->session_key.len = 0;
1662 kfree(server->hostname);
1663 server->hostname = NULL;
1664
1665 task = xchg(&server->tsk, NULL);
1666 if (task)
1667 send_sig(SIGKILL, task, 1);
1668 }
1669
1670 struct TCP_Server_Info *
cifs_get_tcp_session(struct smb3_fs_context * ctx,struct TCP_Server_Info * primary_server)1671 cifs_get_tcp_session(struct smb3_fs_context *ctx,
1672 struct TCP_Server_Info *primary_server)
1673 {
1674 struct TCP_Server_Info *tcp_ses = NULL;
1675 int rc;
1676
1677 cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1678
1679 /* see if we already have a matching tcp_ses */
1680 tcp_ses = cifs_find_tcp_session(ctx);
1681 if (tcp_ses)
1682 return tcp_ses;
1683
1684 tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1685 if (!tcp_ses) {
1686 rc = -ENOMEM;
1687 goto out_err;
1688 }
1689
1690 tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
1691 if (!tcp_ses->hostname) {
1692 rc = -ENOMEM;
1693 goto out_err;
1694 }
1695
1696 if (ctx->leaf_fullpath) {
1697 tcp_ses->leaf_fullpath = kstrdup(ctx->leaf_fullpath, GFP_KERNEL);
1698 if (!tcp_ses->leaf_fullpath) {
1699 rc = -ENOMEM;
1700 goto out_err;
1701 }
1702 }
1703
1704 if (ctx->nosharesock)
1705 tcp_ses->nosharesock = true;
1706
1707 tcp_ses->ops = ctx->ops;
1708 tcp_ses->vals = ctx->vals;
1709 cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1710
1711 tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1712 tcp_ses->noblockcnt = ctx->rootfs;
1713 tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1714 tcp_ses->noautotune = ctx->noautotune;
1715 tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1716 tcp_ses->rdma = ctx->rdma;
1717 tcp_ses->in_flight = 0;
1718 tcp_ses->max_in_flight = 0;
1719 tcp_ses->credits = 1;
1720 if (primary_server) {
1721 spin_lock(&cifs_tcp_ses_lock);
1722 ++primary_server->srv_count;
1723 spin_unlock(&cifs_tcp_ses_lock);
1724 tcp_ses->primary_server = primary_server;
1725 }
1726 init_waitqueue_head(&tcp_ses->response_q);
1727 init_waitqueue_head(&tcp_ses->request_q);
1728 INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1729 mutex_init(&tcp_ses->_srv_mutex);
1730 memcpy(tcp_ses->workstation_RFC1001_name,
1731 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1732 memcpy(tcp_ses->server_RFC1001_name,
1733 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1734 tcp_ses->session_estab = false;
1735 tcp_ses->sequence_number = 0;
1736 tcp_ses->channel_sequence_num = 0; /* only tracked for primary channel */
1737 tcp_ses->reconnect_instance = 1;
1738 tcp_ses->lstrp = jiffies;
1739 tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1740 spin_lock_init(&tcp_ses->req_lock);
1741 spin_lock_init(&tcp_ses->srv_lock);
1742 spin_lock_init(&tcp_ses->mid_lock);
1743 INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1744 INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1745 INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1746 INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1747 mutex_init(&tcp_ses->reconnect_mutex);
1748 #ifdef CONFIG_CIFS_DFS_UPCALL
1749 mutex_init(&tcp_ses->refpath_lock);
1750 #endif
1751 memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1752 sizeof(tcp_ses->srcaddr));
1753 memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1754 sizeof(tcp_ses->dstaddr));
1755 if (ctx->use_client_guid)
1756 memcpy(tcp_ses->client_guid, ctx->client_guid,
1757 SMB2_CLIENT_GUID_SIZE);
1758 else
1759 generate_random_uuid(tcp_ses->client_guid);
1760 /*
1761 * at this point we are the only ones with the pointer
1762 * to the struct since the kernel thread not created yet
1763 * no need to spinlock this init of tcpStatus or srv_count
1764 */
1765 tcp_ses->tcpStatus = CifsNew;
1766 ++tcp_ses->srv_count;
1767
1768 if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1769 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1770 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1771 else
1772 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1773 if (tcp_ses->rdma) {
1774 #ifndef CONFIG_CIFS_SMB_DIRECT
1775 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1776 rc = -ENOENT;
1777 goto out_err_crypto_release;
1778 #endif
1779 tcp_ses->smbd_conn = smbd_get_connection(
1780 tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1781 if (tcp_ses->smbd_conn) {
1782 cifs_dbg(VFS, "RDMA transport established\n");
1783 rc = 0;
1784 goto smbd_connected;
1785 } else {
1786 rc = -ENOENT;
1787 goto out_err_crypto_release;
1788 }
1789 }
1790 rc = ip_connect(tcp_ses);
1791 if (rc < 0) {
1792 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1793 goto out_err_crypto_release;
1794 }
1795 smbd_connected:
1796 /*
1797 * since we're in a cifs function already, we know that
1798 * this will succeed. No need for try_module_get().
1799 */
1800 __module_get(THIS_MODULE);
1801 tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1802 tcp_ses, "cifsd");
1803 if (IS_ERR(tcp_ses->tsk)) {
1804 rc = PTR_ERR(tcp_ses->tsk);
1805 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1806 module_put(THIS_MODULE);
1807 goto out_err_crypto_release;
1808 }
1809 tcp_ses->min_offload = ctx->min_offload;
1810 tcp_ses->retrans = ctx->retrans;
1811 /*
1812 * at this point we are the only ones with the pointer
1813 * to the struct since the kernel thread not created yet
1814 * no need to spinlock this update of tcpStatus
1815 */
1816 spin_lock(&tcp_ses->srv_lock);
1817 tcp_ses->tcpStatus = CifsNeedNegotiate;
1818 spin_unlock(&tcp_ses->srv_lock);
1819
1820 if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1821 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1822 else
1823 tcp_ses->max_credits = ctx->max_credits;
1824
1825 tcp_ses->nr_targets = 1;
1826 tcp_ses->ignore_signature = ctx->ignore_signature;
1827 /* thread spawned, put it on the list */
1828 spin_lock(&cifs_tcp_ses_lock);
1829 list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1830 spin_unlock(&cifs_tcp_ses_lock);
1831
1832 /* queue echo request delayed work */
1833 queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1834
1835 return tcp_ses;
1836
1837 out_err_crypto_release:
1838 cifs_crypto_secmech_release(tcp_ses);
1839
1840 put_net(cifs_net_ns(tcp_ses));
1841
1842 out_err:
1843 if (tcp_ses) {
1844 if (SERVER_IS_CHAN(tcp_ses))
1845 cifs_put_tcp_session(tcp_ses->primary_server, false);
1846 kfree(tcp_ses->hostname);
1847 kfree(tcp_ses->leaf_fullpath);
1848 if (tcp_ses->ssocket)
1849 sock_release(tcp_ses->ssocket);
1850 kfree(tcp_ses);
1851 }
1852 return ERR_PTR(rc);
1853 }
1854
1855 /* this function must be called with ses_lock and chan_lock held */
match_session(struct cifs_ses * ses,struct smb3_fs_context * ctx)1856 static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1857 {
1858 if (ctx->sectype != Unspecified &&
1859 ctx->sectype != ses->sectype)
1860 return 0;
1861
1862 /*
1863 * If an existing session is limited to less channels than
1864 * requested, it should not be reused
1865 */
1866 if (ses->chan_max < ctx->max_channels)
1867 return 0;
1868
1869 switch (ses->sectype) {
1870 case Kerberos:
1871 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1872 return 0;
1873 break;
1874 default:
1875 /* NULL username means anonymous session */
1876 if (ses->user_name == NULL) {
1877 if (!ctx->nullauth)
1878 return 0;
1879 break;
1880 }
1881
1882 /* anything else takes username/password */
1883 if (strncmp(ses->user_name,
1884 ctx->username ? ctx->username : "",
1885 CIFS_MAX_USERNAME_LEN))
1886 return 0;
1887 if ((ctx->username && strlen(ctx->username) != 0) &&
1888 ses->password != NULL &&
1889 strncmp(ses->password,
1890 ctx->password ? ctx->password : "",
1891 CIFS_MAX_PASSWORD_LEN))
1892 return 0;
1893 }
1894
1895 if (strcmp(ctx->local_nls->charset, ses->local_nls->charset))
1896 return 0;
1897
1898 return 1;
1899 }
1900
1901 /**
1902 * cifs_setup_ipc - helper to setup the IPC tcon for the session
1903 * @ses: smb session to issue the request on
1904 * @ctx: the superblock configuration context to use for building the
1905 * new tree connection for the IPC (interprocess communication RPC)
1906 *
1907 * A new IPC connection is made and stored in the session
1908 * tcon_ipc. The IPC tcon has the same lifetime as the session.
1909 */
1910 static int
cifs_setup_ipc(struct cifs_ses * ses,struct smb3_fs_context * ctx)1911 cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1912 {
1913 int rc = 0, xid;
1914 struct cifs_tcon *tcon;
1915 char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1916 bool seal = false;
1917 struct TCP_Server_Info *server = ses->server;
1918
1919 /*
1920 * If the mount request that resulted in the creation of the
1921 * session requires encryption, force IPC to be encrypted too.
1922 */
1923 if (ctx->seal) {
1924 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1925 seal = true;
1926 else {
1927 cifs_server_dbg(VFS,
1928 "IPC: server doesn't support encryption\n");
1929 return -EOPNOTSUPP;
1930 }
1931 }
1932
1933 /* no need to setup directory caching on IPC share, so pass in false */
1934 tcon = tcon_info_alloc(false);
1935 if (tcon == NULL)
1936 return -ENOMEM;
1937
1938 spin_lock(&server->srv_lock);
1939 scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1940 spin_unlock(&server->srv_lock);
1941
1942 xid = get_xid();
1943 tcon->ses = ses;
1944 tcon->ipc = true;
1945 tcon->seal = seal;
1946 rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1947 free_xid(xid);
1948
1949 if (rc) {
1950 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1951 tconInfoFree(tcon);
1952 goto out;
1953 }
1954
1955 cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
1956
1957 spin_lock(&tcon->tc_lock);
1958 tcon->status = TID_GOOD;
1959 spin_unlock(&tcon->tc_lock);
1960 ses->tcon_ipc = tcon;
1961 out:
1962 return rc;
1963 }
1964
1965 /**
1966 * cifs_free_ipc - helper to release the session IPC tcon
1967 * @ses: smb session to unmount the IPC from
1968 *
1969 * Needs to be called everytime a session is destroyed.
1970 *
1971 * On session close, the IPC is closed and the server must release all tcons of the session.
1972 * No need to send a tree disconnect here.
1973 *
1974 * Besides, it will make the server to not close durable and resilient files on session close, as
1975 * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1976 */
1977 static int
cifs_free_ipc(struct cifs_ses * ses)1978 cifs_free_ipc(struct cifs_ses *ses)
1979 {
1980 struct cifs_tcon *tcon = ses->tcon_ipc;
1981
1982 if (tcon == NULL)
1983 return 0;
1984
1985 tconInfoFree(tcon);
1986 ses->tcon_ipc = NULL;
1987 return 0;
1988 }
1989
1990 static struct cifs_ses *
cifs_find_smb_ses(struct TCP_Server_Info * server,struct smb3_fs_context * ctx)1991 cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1992 {
1993 struct cifs_ses *ses, *ret = NULL;
1994
1995 spin_lock(&cifs_tcp_ses_lock);
1996 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1997 spin_lock(&ses->ses_lock);
1998 if (ses->ses_status == SES_EXITING) {
1999 spin_unlock(&ses->ses_lock);
2000 continue;
2001 }
2002 spin_lock(&ses->chan_lock);
2003 if (match_session(ses, ctx)) {
2004 spin_unlock(&ses->chan_lock);
2005 spin_unlock(&ses->ses_lock);
2006 ret = ses;
2007 break;
2008 }
2009 spin_unlock(&ses->chan_lock);
2010 spin_unlock(&ses->ses_lock);
2011 }
2012 if (ret)
2013 cifs_smb_ses_inc_refcount(ret);
2014 spin_unlock(&cifs_tcp_ses_lock);
2015 return ret;
2016 }
2017
__cifs_put_smb_ses(struct cifs_ses * ses)2018 void __cifs_put_smb_ses(struct cifs_ses *ses)
2019 {
2020 struct TCP_Server_Info *server = ses->server;
2021 unsigned int xid;
2022 size_t i;
2023 int rc;
2024
2025 spin_lock(&ses->ses_lock);
2026 if (ses->ses_status == SES_EXITING) {
2027 spin_unlock(&ses->ses_lock);
2028 return;
2029 }
2030 spin_unlock(&ses->ses_lock);
2031
2032 cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
2033 cifs_dbg(FYI,
2034 "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
2035
2036 spin_lock(&cifs_tcp_ses_lock);
2037 if (--ses->ses_count > 0) {
2038 spin_unlock(&cifs_tcp_ses_lock);
2039 return;
2040 }
2041 spin_lock(&ses->ses_lock);
2042 if (ses->ses_status == SES_GOOD)
2043 ses->ses_status = SES_EXITING;
2044 spin_unlock(&ses->ses_lock);
2045 spin_unlock(&cifs_tcp_ses_lock);
2046
2047 /* ses_count can never go negative */
2048 WARN_ON(ses->ses_count < 0);
2049
2050 spin_lock(&ses->ses_lock);
2051 if (ses->ses_status == SES_EXITING && server->ops->logoff) {
2052 spin_unlock(&ses->ses_lock);
2053 cifs_free_ipc(ses);
2054 xid = get_xid();
2055 rc = server->ops->logoff(xid, ses);
2056 if (rc)
2057 cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
2058 __func__, rc);
2059 _free_xid(xid);
2060 } else {
2061 spin_unlock(&ses->ses_lock);
2062 cifs_free_ipc(ses);
2063 }
2064
2065 spin_lock(&cifs_tcp_ses_lock);
2066 list_del_init(&ses->smb_ses_list);
2067 spin_unlock(&cifs_tcp_ses_lock);
2068
2069 /* close any extra channels */
2070 for (i = 1; i < ses->chan_count; i++) {
2071 if (ses->chans[i].iface) {
2072 kref_put(&ses->chans[i].iface->refcount, release_iface);
2073 ses->chans[i].iface = NULL;
2074 }
2075 cifs_put_tcp_session(ses->chans[i].server, 0);
2076 ses->chans[i].server = NULL;
2077 }
2078
2079 /* we now account for primary channel in iface->refcount */
2080 if (ses->chans[0].iface) {
2081 kref_put(&ses->chans[0].iface->refcount, release_iface);
2082 ses->chans[0].server = NULL;
2083 }
2084
2085 sesInfoFree(ses);
2086 cifs_put_tcp_session(server, 0);
2087 }
2088
2089 #ifdef CONFIG_KEYS
2090
2091 /* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
2092 #define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
2093
2094 /* Populate username and pw fields from keyring if possible */
2095 static int
cifs_set_cifscreds(struct smb3_fs_context * ctx,struct cifs_ses * ses)2096 cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
2097 {
2098 int rc = 0;
2099 int is_domain = 0;
2100 const char *delim, *payload;
2101 char *desc;
2102 ssize_t len;
2103 struct key *key;
2104 struct TCP_Server_Info *server = ses->server;
2105 struct sockaddr_in *sa;
2106 struct sockaddr_in6 *sa6;
2107 const struct user_key_payload *upayload;
2108
2109 desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
2110 if (!desc)
2111 return -ENOMEM;
2112
2113 /* try to find an address key first */
2114 switch (server->dstaddr.ss_family) {
2115 case AF_INET:
2116 sa = (struct sockaddr_in *)&server->dstaddr;
2117 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
2118 break;
2119 case AF_INET6:
2120 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
2121 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
2122 break;
2123 default:
2124 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
2125 server->dstaddr.ss_family);
2126 rc = -EINVAL;
2127 goto out_err;
2128 }
2129
2130 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2131 key = request_key(&key_type_logon, desc, "");
2132 if (IS_ERR(key)) {
2133 if (!ses->domainName) {
2134 cifs_dbg(FYI, "domainName is NULL\n");
2135 rc = PTR_ERR(key);
2136 goto out_err;
2137 }
2138
2139 /* didn't work, try to find a domain key */
2140 sprintf(desc, "cifs:d:%s", ses->domainName);
2141 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2142 key = request_key(&key_type_logon, desc, "");
2143 if (IS_ERR(key)) {
2144 rc = PTR_ERR(key);
2145 goto out_err;
2146 }
2147 is_domain = 1;
2148 }
2149
2150 down_read(&key->sem);
2151 upayload = user_key_payload_locked(key);
2152 if (IS_ERR_OR_NULL(upayload)) {
2153 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
2154 goto out_key_put;
2155 }
2156
2157 /* find first : in payload */
2158 payload = upayload->data;
2159 delim = strnchr(payload, upayload->datalen, ':');
2160 cifs_dbg(FYI, "payload=%s\n", payload);
2161 if (!delim) {
2162 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
2163 upayload->datalen);
2164 rc = -EINVAL;
2165 goto out_key_put;
2166 }
2167
2168 len = delim - payload;
2169 if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
2170 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
2171 len);
2172 rc = -EINVAL;
2173 goto out_key_put;
2174 }
2175
2176 ctx->username = kstrndup(payload, len, GFP_KERNEL);
2177 if (!ctx->username) {
2178 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
2179 len);
2180 rc = -ENOMEM;
2181 goto out_key_put;
2182 }
2183 cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
2184
2185 len = key->datalen - (len + 1);
2186 if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
2187 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
2188 rc = -EINVAL;
2189 kfree(ctx->username);
2190 ctx->username = NULL;
2191 goto out_key_put;
2192 }
2193
2194 ++delim;
2195 ctx->password = kstrndup(delim, len, GFP_KERNEL);
2196 if (!ctx->password) {
2197 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
2198 len);
2199 rc = -ENOMEM;
2200 kfree(ctx->username);
2201 ctx->username = NULL;
2202 goto out_key_put;
2203 }
2204
2205 /*
2206 * If we have a domain key then we must set the domainName in the
2207 * for the request.
2208 */
2209 if (is_domain && ses->domainName) {
2210 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
2211 if (!ctx->domainname) {
2212 cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
2213 len);
2214 rc = -ENOMEM;
2215 kfree(ctx->username);
2216 ctx->username = NULL;
2217 kfree_sensitive(ctx->password);
2218 ctx->password = NULL;
2219 goto out_key_put;
2220 }
2221 }
2222
2223 strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
2224
2225 out_key_put:
2226 up_read(&key->sem);
2227 key_put(key);
2228 out_err:
2229 kfree(desc);
2230 cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
2231 return rc;
2232 }
2233 #else /* ! CONFIG_KEYS */
2234 static inline int
cifs_set_cifscreds(struct smb3_fs_context * ctx,struct cifs_ses * ses)2235 cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
2236 struct cifs_ses *ses __attribute__((unused)))
2237 {
2238 return -ENOSYS;
2239 }
2240 #endif /* CONFIG_KEYS */
2241
2242 /**
2243 * cifs_get_smb_ses - get a session matching @ctx data from @server
2244 * @server: server to setup the session to
2245 * @ctx: superblock configuration context to use to setup the session
2246 *
2247 * This function assumes it is being called from cifs_mount() where we
2248 * already got a server reference (server refcount +1). See
2249 * cifs_get_tcon() for refcount explanations.
2250 */
2251 struct cifs_ses *
cifs_get_smb_ses(struct TCP_Server_Info * server,struct smb3_fs_context * ctx)2252 cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
2253 {
2254 int rc = 0;
2255 unsigned int xid;
2256 struct cifs_ses *ses;
2257 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2258 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2259
2260 xid = get_xid();
2261
2262 ses = cifs_find_smb_ses(server, ctx);
2263 if (ses) {
2264 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
2265 ses->ses_status);
2266
2267 spin_lock(&ses->chan_lock);
2268 if (cifs_chan_needs_reconnect(ses, server)) {
2269 spin_unlock(&ses->chan_lock);
2270 cifs_dbg(FYI, "Session needs reconnect\n");
2271
2272 mutex_lock(&ses->session_mutex);
2273 rc = cifs_negotiate_protocol(xid, ses, server);
2274 if (rc) {
2275 mutex_unlock(&ses->session_mutex);
2276 /* problem -- put our ses reference */
2277 cifs_put_smb_ses(ses);
2278 free_xid(xid);
2279 return ERR_PTR(rc);
2280 }
2281
2282 rc = cifs_setup_session(xid, ses, server,
2283 ctx->local_nls);
2284 if (rc) {
2285 mutex_unlock(&ses->session_mutex);
2286 /* problem -- put our reference */
2287 cifs_put_smb_ses(ses);
2288 free_xid(xid);
2289 return ERR_PTR(rc);
2290 }
2291 mutex_unlock(&ses->session_mutex);
2292
2293 spin_lock(&ses->chan_lock);
2294 }
2295 spin_unlock(&ses->chan_lock);
2296
2297 /* existing SMB ses has a server reference already */
2298 cifs_put_tcp_session(server, 0);
2299 free_xid(xid);
2300 return ses;
2301 }
2302
2303 rc = -ENOMEM;
2304
2305 cifs_dbg(FYI, "Existing smb sess not found\n");
2306 ses = sesInfoAlloc();
2307 if (ses == NULL)
2308 goto get_ses_fail;
2309
2310 /* new SMB session uses our server ref */
2311 ses->server = server;
2312 if (server->dstaddr.ss_family == AF_INET6)
2313 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
2314 else
2315 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
2316
2317 if (ctx->username) {
2318 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
2319 if (!ses->user_name)
2320 goto get_ses_fail;
2321 }
2322
2323 /* ctx->password freed at unmount */
2324 if (ctx->password) {
2325 ses->password = kstrdup(ctx->password, GFP_KERNEL);
2326 if (!ses->password)
2327 goto get_ses_fail;
2328 }
2329 if (ctx->domainname) {
2330 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
2331 if (!ses->domainName)
2332 goto get_ses_fail;
2333 }
2334
2335 strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
2336
2337 if (ctx->domainauto)
2338 ses->domainAuto = ctx->domainauto;
2339 ses->cred_uid = ctx->cred_uid;
2340 ses->linux_uid = ctx->linux_uid;
2341
2342 ses->sectype = ctx->sectype;
2343 ses->sign = ctx->sign;
2344 ses->local_nls = load_nls(ctx->local_nls->charset);
2345
2346 /* add server as first channel */
2347 spin_lock(&ses->chan_lock);
2348 ses->chans[0].server = server;
2349 ses->chan_count = 1;
2350 ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
2351 ses->chans_need_reconnect = 1;
2352 spin_unlock(&ses->chan_lock);
2353
2354 mutex_lock(&ses->session_mutex);
2355 rc = cifs_negotiate_protocol(xid, ses, server);
2356 if (!rc)
2357 rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
2358 mutex_unlock(&ses->session_mutex);
2359
2360 /* each channel uses a different signing key */
2361 spin_lock(&ses->chan_lock);
2362 memcpy(ses->chans[0].signkey, ses->smb3signingkey,
2363 sizeof(ses->smb3signingkey));
2364 spin_unlock(&ses->chan_lock);
2365
2366 if (rc)
2367 goto get_ses_fail;
2368
2369 /*
2370 * success, put it on the list and add it as first channel
2371 * note: the session becomes active soon after this. So you'll
2372 * need to lock before changing something in the session.
2373 */
2374 spin_lock(&cifs_tcp_ses_lock);
2375 ses->dfs_root_ses = ctx->dfs_root_ses;
2376 if (ses->dfs_root_ses)
2377 ses->dfs_root_ses->ses_count++;
2378 list_add(&ses->smb_ses_list, &server->smb_ses_list);
2379 spin_unlock(&cifs_tcp_ses_lock);
2380
2381 cifs_setup_ipc(ses, ctx);
2382
2383 free_xid(xid);
2384
2385 return ses;
2386
2387 get_ses_fail:
2388 sesInfoFree(ses);
2389 free_xid(xid);
2390 return ERR_PTR(rc);
2391 }
2392
2393 /* this function must be called with tc_lock held */
match_tcon(struct cifs_tcon * tcon,struct smb3_fs_context * ctx)2394 static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
2395 {
2396 struct TCP_Server_Info *server = tcon->ses->server;
2397
2398 if (tcon->status == TID_EXITING)
2399 return 0;
2400
2401 if (tcon->origin_fullpath) {
2402 if (!ctx->source ||
2403 !dfs_src_pathname_equal(ctx->source,
2404 tcon->origin_fullpath))
2405 return 0;
2406 } else if (!server->leaf_fullpath &&
2407 strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE)) {
2408 return 0;
2409 }
2410 if (tcon->seal != ctx->seal)
2411 return 0;
2412 if (tcon->snapshot_time != ctx->snapshot_time)
2413 return 0;
2414 if (tcon->handle_timeout != ctx->handle_timeout)
2415 return 0;
2416 if (tcon->no_lease != ctx->no_lease)
2417 return 0;
2418 if (tcon->nodelete != ctx->nodelete)
2419 return 0;
2420 return 1;
2421 }
2422
2423 static struct cifs_tcon *
cifs_find_tcon(struct cifs_ses * ses,struct smb3_fs_context * ctx)2424 cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2425 {
2426 struct cifs_tcon *tcon;
2427
2428 spin_lock(&cifs_tcp_ses_lock);
2429 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
2430 spin_lock(&tcon->tc_lock);
2431 if (!match_tcon(tcon, ctx)) {
2432 spin_unlock(&tcon->tc_lock);
2433 continue;
2434 }
2435 ++tcon->tc_count;
2436 spin_unlock(&tcon->tc_lock);
2437 spin_unlock(&cifs_tcp_ses_lock);
2438 return tcon;
2439 }
2440 spin_unlock(&cifs_tcp_ses_lock);
2441 return NULL;
2442 }
2443
2444 void
cifs_put_tcon(struct cifs_tcon * tcon)2445 cifs_put_tcon(struct cifs_tcon *tcon)
2446 {
2447 unsigned int xid;
2448 struct cifs_ses *ses;
2449
2450 /*
2451 * IPC tcon share the lifetime of their session and are
2452 * destroyed in the session put function
2453 */
2454 if (tcon == NULL || tcon->ipc)
2455 return;
2456
2457 ses = tcon->ses;
2458 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2459 spin_lock(&cifs_tcp_ses_lock);
2460 spin_lock(&tcon->tc_lock);
2461 if (--tcon->tc_count > 0) {
2462 spin_unlock(&tcon->tc_lock);
2463 spin_unlock(&cifs_tcp_ses_lock);
2464 return;
2465 }
2466
2467 /* tc_count can never go negative */
2468 WARN_ON(tcon->tc_count < 0);
2469
2470 list_del_init(&tcon->tcon_list);
2471 tcon->status = TID_EXITING;
2472 spin_unlock(&tcon->tc_lock);
2473 spin_unlock(&cifs_tcp_ses_lock);
2474
2475 /* cancel polling of interfaces */
2476 cancel_delayed_work_sync(&tcon->query_interfaces);
2477 #ifdef CONFIG_CIFS_DFS_UPCALL
2478 cancel_delayed_work_sync(&tcon->dfs_cache_work);
2479 #endif
2480
2481 if (tcon->use_witness) {
2482 int rc;
2483
2484 rc = cifs_swn_unregister(tcon);
2485 if (rc < 0) {
2486 cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2487 __func__, rc);
2488 }
2489 }
2490
2491 xid = get_xid();
2492 if (ses->server->ops->tree_disconnect)
2493 ses->server->ops->tree_disconnect(xid, tcon);
2494 _free_xid(xid);
2495
2496 cifs_fscache_release_super_cookie(tcon);
2497 tconInfoFree(tcon);
2498 cifs_put_smb_ses(ses);
2499 }
2500
2501 /**
2502 * cifs_get_tcon - get a tcon matching @ctx data from @ses
2503 * @ses: smb session to issue the request on
2504 * @ctx: the superblock configuration context to use for building the
2505 *
2506 * - tcon refcount is the number of mount points using the tcon.
2507 * - ses refcount is the number of tcon using the session.
2508 *
2509 * 1. This function assumes it is being called from cifs_mount() where
2510 * we already got a session reference (ses refcount +1).
2511 *
2512 * 2. Since we're in the context of adding a mount point, the end
2513 * result should be either:
2514 *
2515 * a) a new tcon already allocated with refcount=1 (1 mount point) and
2516 * its session refcount incremented (1 new tcon). This +1 was
2517 * already done in (1).
2518 *
2519 * b) an existing tcon with refcount+1 (add a mount point to it) and
2520 * identical ses refcount (no new tcon). Because of (1) we need to
2521 * decrement the ses refcount.
2522 */
2523 static struct cifs_tcon *
cifs_get_tcon(struct cifs_ses * ses,struct smb3_fs_context * ctx)2524 cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2525 {
2526 struct cifs_tcon *tcon;
2527 bool nohandlecache;
2528 int rc, xid;
2529
2530 tcon = cifs_find_tcon(ses, ctx);
2531 if (tcon) {
2532 /*
2533 * tcon has refcount already incremented but we need to
2534 * decrement extra ses reference gotten by caller (case b)
2535 */
2536 cifs_dbg(FYI, "Found match on UNC path\n");
2537 cifs_put_smb_ses(ses);
2538 return tcon;
2539 }
2540
2541 if (!ses->server->ops->tree_connect) {
2542 rc = -ENOSYS;
2543 goto out_fail;
2544 }
2545
2546 if (ses->server->dialect >= SMB20_PROT_ID &&
2547 (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING))
2548 nohandlecache = ctx->nohandlecache;
2549 else
2550 nohandlecache = true;
2551 tcon = tcon_info_alloc(!nohandlecache);
2552 if (tcon == NULL) {
2553 rc = -ENOMEM;
2554 goto out_fail;
2555 }
2556 tcon->nohandlecache = nohandlecache;
2557
2558 if (ctx->snapshot_time) {
2559 if (ses->server->vals->protocol_id == 0) {
2560 cifs_dbg(VFS,
2561 "Use SMB2 or later for snapshot mount option\n");
2562 rc = -EOPNOTSUPP;
2563 goto out_fail;
2564 } else
2565 tcon->snapshot_time = ctx->snapshot_time;
2566 }
2567
2568 if (ctx->handle_timeout) {
2569 if (ses->server->vals->protocol_id == 0) {
2570 cifs_dbg(VFS,
2571 "Use SMB2.1 or later for handle timeout option\n");
2572 rc = -EOPNOTSUPP;
2573 goto out_fail;
2574 } else
2575 tcon->handle_timeout = ctx->handle_timeout;
2576 }
2577
2578 tcon->ses = ses;
2579 if (ctx->password) {
2580 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2581 if (!tcon->password) {
2582 rc = -ENOMEM;
2583 goto out_fail;
2584 }
2585 }
2586
2587 if (ctx->seal) {
2588 if (ses->server->vals->protocol_id == 0) {
2589 cifs_dbg(VFS,
2590 "SMB3 or later required for encryption\n");
2591 rc = -EOPNOTSUPP;
2592 goto out_fail;
2593 } else if (tcon->ses->server->capabilities &
2594 SMB2_GLOBAL_CAP_ENCRYPTION)
2595 tcon->seal = true;
2596 else {
2597 cifs_dbg(VFS, "Encryption is not supported on share\n");
2598 rc = -EOPNOTSUPP;
2599 goto out_fail;
2600 }
2601 }
2602
2603 if (ctx->linux_ext) {
2604 if (ses->server->posix_ext_supported) {
2605 tcon->posix_extensions = true;
2606 pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2607 } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
2608 (strcmp(ses->server->vals->version_string,
2609 SMB3ANY_VERSION_STRING) == 0) ||
2610 (strcmp(ses->server->vals->version_string,
2611 SMBDEFAULT_VERSION_STRING) == 0)) {
2612 cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2613 rc = -EOPNOTSUPP;
2614 goto out_fail;
2615 } else {
2616 cifs_dbg(VFS,
2617 "Check vers= mount option. SMB3.11 disabled but required for POSIX extensions\n");
2618 rc = -EOPNOTSUPP;
2619 goto out_fail;
2620 }
2621 }
2622
2623 xid = get_xid();
2624 rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2625 ctx->local_nls);
2626 free_xid(xid);
2627 cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2628 if (rc)
2629 goto out_fail;
2630
2631 tcon->use_persistent = false;
2632 /* check if SMB2 or later, CIFS does not support persistent handles */
2633 if (ctx->persistent) {
2634 if (ses->server->vals->protocol_id == 0) {
2635 cifs_dbg(VFS,
2636 "SMB3 or later required for persistent handles\n");
2637 rc = -EOPNOTSUPP;
2638 goto out_fail;
2639 } else if (ses->server->capabilities &
2640 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2641 tcon->use_persistent = true;
2642 else /* persistent handles requested but not supported */ {
2643 cifs_dbg(VFS,
2644 "Persistent handles not supported on share\n");
2645 rc = -EOPNOTSUPP;
2646 goto out_fail;
2647 }
2648 } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2649 && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2650 && (ctx->nopersistent == false)) {
2651 cifs_dbg(FYI, "enabling persistent handles\n");
2652 tcon->use_persistent = true;
2653 } else if (ctx->resilient) {
2654 if (ses->server->vals->protocol_id == 0) {
2655 cifs_dbg(VFS,
2656 "SMB2.1 or later required for resilient handles\n");
2657 rc = -EOPNOTSUPP;
2658 goto out_fail;
2659 }
2660 tcon->use_resilient = true;
2661 }
2662
2663 tcon->use_witness = false;
2664 if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2665 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2666 if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2667 /*
2668 * Set witness in use flag in first place
2669 * to retry registration in the echo task
2670 */
2671 tcon->use_witness = true;
2672 /* And try to register immediately */
2673 rc = cifs_swn_register(tcon);
2674 if (rc < 0) {
2675 cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2676 goto out_fail;
2677 }
2678 } else {
2679 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2680 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2681 rc = -EOPNOTSUPP;
2682 goto out_fail;
2683 }
2684 } else {
2685 cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2686 rc = -EOPNOTSUPP;
2687 goto out_fail;
2688 }
2689 }
2690
2691 /* If the user really knows what they are doing they can override */
2692 if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2693 if (ctx->cache_ro)
2694 cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2695 else if (ctx->cache_rw)
2696 cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2697 }
2698
2699 if (ctx->no_lease) {
2700 if (ses->server->vals->protocol_id == 0) {
2701 cifs_dbg(VFS,
2702 "SMB2 or later required for nolease option\n");
2703 rc = -EOPNOTSUPP;
2704 goto out_fail;
2705 } else
2706 tcon->no_lease = ctx->no_lease;
2707 }
2708
2709 /*
2710 * We can have only one retry value for a connection to a share so for
2711 * resources mounted more than once to the same server share the last
2712 * value passed in for the retry flag is used.
2713 */
2714 tcon->retry = ctx->retry;
2715 tcon->nocase = ctx->nocase;
2716 tcon->broken_sparse_sup = ctx->no_sparse;
2717 tcon->max_cached_dirs = ctx->max_cached_dirs;
2718 tcon->nodelete = ctx->nodelete;
2719 tcon->local_lease = ctx->local_lease;
2720 INIT_LIST_HEAD(&tcon->pending_opens);
2721 tcon->status = TID_GOOD;
2722
2723 INIT_DELAYED_WORK(&tcon->query_interfaces,
2724 smb2_query_server_interfaces);
2725 if (ses->server->dialect >= SMB30_PROT_ID &&
2726 (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
2727 /* schedule query interfaces poll */
2728 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
2729 (SMB_INTERFACE_POLL_INTERVAL * HZ));
2730 }
2731 #ifdef CONFIG_CIFS_DFS_UPCALL
2732 INIT_DELAYED_WORK(&tcon->dfs_cache_work, dfs_cache_refresh);
2733 #endif
2734 spin_lock(&cifs_tcp_ses_lock);
2735 list_add(&tcon->tcon_list, &ses->tcon_list);
2736 spin_unlock(&cifs_tcp_ses_lock);
2737
2738 return tcon;
2739
2740 out_fail:
2741 tconInfoFree(tcon);
2742 return ERR_PTR(rc);
2743 }
2744
2745 void
cifs_put_tlink(struct tcon_link * tlink)2746 cifs_put_tlink(struct tcon_link *tlink)
2747 {
2748 if (!tlink || IS_ERR(tlink))
2749 return;
2750
2751 if (!atomic_dec_and_test(&tlink->tl_count) ||
2752 test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2753 tlink->tl_time = jiffies;
2754 return;
2755 }
2756
2757 if (!IS_ERR(tlink_tcon(tlink)))
2758 cifs_put_tcon(tlink_tcon(tlink));
2759 kfree(tlink);
2760 }
2761
2762 static int
compare_mount_options(struct super_block * sb,struct cifs_mnt_data * mnt_data)2763 compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2764 {
2765 struct cifs_sb_info *old = CIFS_SB(sb);
2766 struct cifs_sb_info *new = mnt_data->cifs_sb;
2767 unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2768 unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2769
2770 if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2771 return 0;
2772
2773 if (old->mnt_cifs_serverino_autodisabled)
2774 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2775
2776 if (oldflags != newflags)
2777 return 0;
2778
2779 /*
2780 * We want to share sb only if we don't specify an r/wsize or
2781 * specified r/wsize is greater than or equal to existing one.
2782 */
2783 if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2784 return 0;
2785
2786 if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2787 return 0;
2788
2789 if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2790 !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2791 return 0;
2792
2793 if (old->ctx->file_mode != new->ctx->file_mode ||
2794 old->ctx->dir_mode != new->ctx->dir_mode)
2795 return 0;
2796
2797 if (strcmp(old->local_nls->charset, new->local_nls->charset))
2798 return 0;
2799
2800 if (old->ctx->acregmax != new->ctx->acregmax)
2801 return 0;
2802 if (old->ctx->acdirmax != new->ctx->acdirmax)
2803 return 0;
2804 if (old->ctx->closetimeo != new->ctx->closetimeo)
2805 return 0;
2806
2807 return 1;
2808 }
2809
match_prepath(struct super_block * sb,struct cifs_tcon * tcon,struct cifs_mnt_data * mnt_data)2810 static int match_prepath(struct super_block *sb,
2811 struct cifs_tcon *tcon,
2812 struct cifs_mnt_data *mnt_data)
2813 {
2814 struct smb3_fs_context *ctx = mnt_data->ctx;
2815 struct cifs_sb_info *old = CIFS_SB(sb);
2816 struct cifs_sb_info *new = mnt_data->cifs_sb;
2817 bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2818 old->prepath;
2819 bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2820 new->prepath;
2821
2822 if (tcon->origin_fullpath &&
2823 dfs_src_pathname_equal(tcon->origin_fullpath, ctx->source))
2824 return 1;
2825
2826 if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2827 return 1;
2828 else if (!old_set && !new_set)
2829 return 1;
2830
2831 return 0;
2832 }
2833
2834 int
cifs_match_super(struct super_block * sb,void * data)2835 cifs_match_super(struct super_block *sb, void *data)
2836 {
2837 struct cifs_mnt_data *mnt_data = data;
2838 struct smb3_fs_context *ctx;
2839 struct cifs_sb_info *cifs_sb;
2840 struct TCP_Server_Info *tcp_srv;
2841 struct cifs_ses *ses;
2842 struct cifs_tcon *tcon;
2843 struct tcon_link *tlink;
2844 int rc = 0;
2845
2846 spin_lock(&cifs_tcp_ses_lock);
2847 cifs_sb = CIFS_SB(sb);
2848
2849 /* We do not want to use a superblock that has been shutdown */
2850 if (CIFS_MOUNT_SHUTDOWN & cifs_sb->mnt_cifs_flags) {
2851 spin_unlock(&cifs_tcp_ses_lock);
2852 return 0;
2853 }
2854
2855 tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2856 if (IS_ERR_OR_NULL(tlink)) {
2857 pr_warn_once("%s: skip super matching due to bad tlink(%p)\n",
2858 __func__, tlink);
2859 spin_unlock(&cifs_tcp_ses_lock);
2860 return 0;
2861 }
2862 tcon = tlink_tcon(tlink);
2863 ses = tcon->ses;
2864 tcp_srv = ses->server;
2865
2866 ctx = mnt_data->ctx;
2867
2868 spin_lock(&tcp_srv->srv_lock);
2869 spin_lock(&ses->ses_lock);
2870 spin_lock(&ses->chan_lock);
2871 spin_lock(&tcon->tc_lock);
2872 if (!match_server(tcp_srv, ctx, true) ||
2873 !match_session(ses, ctx) ||
2874 !match_tcon(tcon, ctx) ||
2875 !match_prepath(sb, tcon, mnt_data)) {
2876 rc = 0;
2877 goto out;
2878 }
2879
2880 rc = compare_mount_options(sb, mnt_data);
2881 out:
2882 spin_unlock(&tcon->tc_lock);
2883 spin_unlock(&ses->chan_lock);
2884 spin_unlock(&ses->ses_lock);
2885 spin_unlock(&tcp_srv->srv_lock);
2886
2887 spin_unlock(&cifs_tcp_ses_lock);
2888 cifs_put_tlink(tlink);
2889 return rc;
2890 }
2891
2892 #ifdef CONFIG_DEBUG_LOCK_ALLOC
2893 static struct lock_class_key cifs_key[2];
2894 static struct lock_class_key cifs_slock_key[2];
2895
2896 static inline void
cifs_reclassify_socket4(struct socket * sock)2897 cifs_reclassify_socket4(struct socket *sock)
2898 {
2899 struct sock *sk = sock->sk;
2900
2901 BUG_ON(!sock_allow_reclassification(sk));
2902 sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2903 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2904 }
2905
2906 static inline void
cifs_reclassify_socket6(struct socket * sock)2907 cifs_reclassify_socket6(struct socket *sock)
2908 {
2909 struct sock *sk = sock->sk;
2910
2911 BUG_ON(!sock_allow_reclassification(sk));
2912 sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2913 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2914 }
2915 #else
2916 static inline void
cifs_reclassify_socket4(struct socket * sock)2917 cifs_reclassify_socket4(struct socket *sock)
2918 {
2919 }
2920
2921 static inline void
cifs_reclassify_socket6(struct socket * sock)2922 cifs_reclassify_socket6(struct socket *sock)
2923 {
2924 }
2925 #endif
2926
2927 /* See RFC1001 section 14 on representation of Netbios names */
rfc1002mangle(char * target,char * source,unsigned int length)2928 static void rfc1002mangle(char *target, char *source, unsigned int length)
2929 {
2930 unsigned int i, j;
2931
2932 for (i = 0, j = 0; i < (length); i++) {
2933 /* mask a nibble at a time and encode */
2934 target[j] = 'A' + (0x0F & (source[i] >> 4));
2935 target[j+1] = 'A' + (0x0F & source[i]);
2936 j += 2;
2937 }
2938
2939 }
2940
2941 static int
bind_socket(struct TCP_Server_Info * server)2942 bind_socket(struct TCP_Server_Info *server)
2943 {
2944 int rc = 0;
2945
2946 if (server->srcaddr.ss_family != AF_UNSPEC) {
2947 /* Bind to the specified local IP address */
2948 struct socket *socket = server->ssocket;
2949
2950 rc = kernel_bind(socket,
2951 (struct sockaddr *) &server->srcaddr,
2952 sizeof(server->srcaddr));
2953 if (rc < 0) {
2954 struct sockaddr_in *saddr4;
2955 struct sockaddr_in6 *saddr6;
2956
2957 saddr4 = (struct sockaddr_in *)&server->srcaddr;
2958 saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2959 if (saddr6->sin6_family == AF_INET6)
2960 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2961 &saddr6->sin6_addr, rc);
2962 else
2963 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2964 &saddr4->sin_addr.s_addr, rc);
2965 }
2966 }
2967 return rc;
2968 }
2969
2970 static int
ip_rfc1001_connect(struct TCP_Server_Info * server)2971 ip_rfc1001_connect(struct TCP_Server_Info *server)
2972 {
2973 int rc = 0;
2974 /*
2975 * some servers require RFC1001 sessinit before sending
2976 * negprot - BB check reconnection in case where second
2977 * sessinit is sent but no second negprot
2978 */
2979 struct rfc1002_session_packet req = {};
2980 struct smb_hdr *smb_buf = (struct smb_hdr *)&req;
2981 unsigned int len;
2982
2983 req.trailer.session_req.called_len = sizeof(req.trailer.session_req.called_name);
2984
2985 if (server->server_RFC1001_name[0] != 0)
2986 rfc1002mangle(req.trailer.session_req.called_name,
2987 server->server_RFC1001_name,
2988 RFC1001_NAME_LEN_WITH_NULL);
2989 else
2990 rfc1002mangle(req.trailer.session_req.called_name,
2991 DEFAULT_CIFS_CALLED_NAME,
2992 RFC1001_NAME_LEN_WITH_NULL);
2993
2994 req.trailer.session_req.calling_len = sizeof(req.trailer.session_req.calling_name);
2995
2996 /* calling name ends in null (byte 16) from old smb convention */
2997 if (server->workstation_RFC1001_name[0] != 0)
2998 rfc1002mangle(req.trailer.session_req.calling_name,
2999 server->workstation_RFC1001_name,
3000 RFC1001_NAME_LEN_WITH_NULL);
3001 else
3002 rfc1002mangle(req.trailer.session_req.calling_name,
3003 "LINUX_CIFS_CLNT",
3004 RFC1001_NAME_LEN_WITH_NULL);
3005
3006 /*
3007 * As per rfc1002, @len must be the number of bytes that follows the
3008 * length field of a rfc1002 session request payload.
3009 */
3010 len = sizeof(req) - offsetof(struct rfc1002_session_packet, trailer.session_req);
3011
3012 smb_buf->smb_buf_length = cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | len);
3013 rc = smb_send(server, smb_buf, len);
3014 /*
3015 * RFC1001 layer in at least one server requires very short break before
3016 * negprot presumably because not expecting negprot to follow so fast.
3017 * This is a simple solution that works without complicating the code
3018 * and causes no significant slowing down on mount for everyone else
3019 */
3020 usleep_range(1000, 2000);
3021
3022 return rc;
3023 }
3024
3025 static int
generic_ip_connect(struct TCP_Server_Info * server)3026 generic_ip_connect(struct TCP_Server_Info *server)
3027 {
3028 struct sockaddr *saddr;
3029 struct socket *socket;
3030 int slen, sfamily;
3031 __be16 sport;
3032 int rc = 0;
3033
3034 saddr = (struct sockaddr *) &server->dstaddr;
3035
3036 if (server->dstaddr.ss_family == AF_INET6) {
3037 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
3038
3039 sport = ipv6->sin6_port;
3040 slen = sizeof(struct sockaddr_in6);
3041 sfamily = AF_INET6;
3042 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
3043 ntohs(sport));
3044 } else {
3045 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
3046
3047 sport = ipv4->sin_port;
3048 slen = sizeof(struct sockaddr_in);
3049 sfamily = AF_INET;
3050 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
3051 ntohs(sport));
3052 }
3053
3054 if (server->ssocket) {
3055 socket = server->ssocket;
3056 } else {
3057 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
3058 IPPROTO_TCP, &server->ssocket, 1);
3059 if (rc < 0) {
3060 cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
3061 return rc;
3062 }
3063
3064 /* BB other socket options to set KEEPALIVE, NODELAY? */
3065 cifs_dbg(FYI, "Socket created\n");
3066 socket = server->ssocket;
3067 socket->sk->sk_allocation = GFP_NOFS;
3068 socket->sk->sk_use_task_frag = false;
3069 if (sfamily == AF_INET6)
3070 cifs_reclassify_socket6(socket);
3071 else
3072 cifs_reclassify_socket4(socket);
3073 }
3074
3075 rc = bind_socket(server);
3076 if (rc < 0)
3077 return rc;
3078
3079 /*
3080 * Eventually check for other socket options to change from
3081 * the default. sock_setsockopt not used because it expects
3082 * user space buffer
3083 */
3084 socket->sk->sk_rcvtimeo = 7 * HZ;
3085 socket->sk->sk_sndtimeo = 5 * HZ;
3086
3087 /* make the bufsizes depend on wsize/rsize and max requests */
3088 if (server->noautotune) {
3089 if (socket->sk->sk_sndbuf < (200 * 1024))
3090 socket->sk->sk_sndbuf = 200 * 1024;
3091 if (socket->sk->sk_rcvbuf < (140 * 1024))
3092 socket->sk->sk_rcvbuf = 140 * 1024;
3093 }
3094
3095 if (server->tcp_nodelay)
3096 tcp_sock_set_nodelay(socket->sk);
3097
3098 cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
3099 socket->sk->sk_sndbuf,
3100 socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
3101
3102 rc = kernel_connect(socket, saddr, slen,
3103 server->noblockcnt ? O_NONBLOCK : 0);
3104 /*
3105 * When mounting SMB root file systems, we do not want to block in
3106 * connect. Otherwise bail out and then let cifs_reconnect() perform
3107 * reconnect failover - if possible.
3108 */
3109 if (server->noblockcnt && rc == -EINPROGRESS)
3110 rc = 0;
3111 if (rc < 0) {
3112 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3113 trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
3114 sock_release(socket);
3115 server->ssocket = NULL;
3116 return rc;
3117 }
3118 trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
3119 if (sport == htons(RFC1001_PORT))
3120 rc = ip_rfc1001_connect(server);
3121
3122 return rc;
3123 }
3124
3125 static int
ip_connect(struct TCP_Server_Info * server)3126 ip_connect(struct TCP_Server_Info *server)
3127 {
3128 __be16 *sport;
3129 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3130 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3131
3132 if (server->dstaddr.ss_family == AF_INET6)
3133 sport = &addr6->sin6_port;
3134 else
3135 sport = &addr->sin_port;
3136
3137 if (*sport == 0) {
3138 int rc;
3139
3140 /* try with 445 port at first */
3141 *sport = htons(CIFS_PORT);
3142
3143 rc = generic_ip_connect(server);
3144 if (rc >= 0)
3145 return rc;
3146
3147 /* if it failed, try with 139 port */
3148 *sport = htons(RFC1001_PORT);
3149 }
3150
3151 return generic_ip_connect(server);
3152 }
3153
3154 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
reset_cifs_unix_caps(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,struct smb3_fs_context * ctx)3155 void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3156 struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3157 {
3158 /*
3159 * If we are reconnecting then should we check to see if
3160 * any requested capabilities changed locally e.g. via
3161 * remount but we can not do much about it here
3162 * if they have (even if we could detect it by the following)
3163 * Perhaps we could add a backpointer to array of sb from tcon
3164 * or if we change to make all sb to same share the same
3165 * sb as NFS - then we only have one backpointer to sb.
3166 * What if we wanted to mount the server share twice once with
3167 * and once without posixacls or posix paths?
3168 */
3169 __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3170
3171 if (ctx && ctx->no_linux_ext) {
3172 tcon->fsUnixInfo.Capability = 0;
3173 tcon->unix_ext = 0; /* Unix Extensions disabled */
3174 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
3175 return;
3176 } else if (ctx)
3177 tcon->unix_ext = 1; /* Unix Extensions supported */
3178
3179 if (!tcon->unix_ext) {
3180 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
3181 return;
3182 }
3183
3184 if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
3185 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3186
3187 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
3188 /*
3189 * check for reconnect case in which we do not
3190 * want to change the mount behavior if we can avoid it
3191 */
3192 if (ctx == NULL) {
3193 /*
3194 * turn off POSIX ACL and PATHNAMES if not set
3195 * originally at mount time
3196 */
3197 if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
3198 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3199 if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3200 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3201 cifs_dbg(VFS, "POSIXPATH support change\n");
3202 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3203 } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3204 cifs_dbg(VFS, "possible reconnect error\n");
3205 cifs_dbg(VFS, "server disabled POSIX path support\n");
3206 }
3207 }
3208
3209 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3210 cifs_dbg(VFS, "per-share encryption not supported yet\n");
3211
3212 cap &= CIFS_UNIX_CAP_MASK;
3213 if (ctx && ctx->no_psx_acl)
3214 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3215 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
3216 cifs_dbg(FYI, "negotiated posix acl support\n");
3217 if (cifs_sb)
3218 cifs_sb->mnt_cifs_flags |=
3219 CIFS_MOUNT_POSIXACL;
3220 }
3221
3222 if (ctx && ctx->posix_paths == 0)
3223 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3224 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
3225 cifs_dbg(FYI, "negotiate posix pathnames\n");
3226 if (cifs_sb)
3227 cifs_sb->mnt_cifs_flags |=
3228 CIFS_MOUNT_POSIX_PATHS;
3229 }
3230
3231 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
3232 #ifdef CONFIG_CIFS_DEBUG2
3233 if (cap & CIFS_UNIX_FCNTL_CAP)
3234 cifs_dbg(FYI, "FCNTL cap\n");
3235 if (cap & CIFS_UNIX_EXTATTR_CAP)
3236 cifs_dbg(FYI, "EXTATTR cap\n");
3237 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3238 cifs_dbg(FYI, "POSIX path cap\n");
3239 if (cap & CIFS_UNIX_XATTR_CAP)
3240 cifs_dbg(FYI, "XATTR cap\n");
3241 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
3242 cifs_dbg(FYI, "POSIX ACL cap\n");
3243 if (cap & CIFS_UNIX_LARGE_READ_CAP)
3244 cifs_dbg(FYI, "very large read cap\n");
3245 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
3246 cifs_dbg(FYI, "very large write cap\n");
3247 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
3248 cifs_dbg(FYI, "transport encryption cap\n");
3249 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3250 cifs_dbg(FYI, "mandatory transport encryption cap\n");
3251 #endif /* CIFS_DEBUG2 */
3252 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
3253 if (ctx == NULL)
3254 cifs_dbg(FYI, "resetting capabilities failed\n");
3255 else
3256 cifs_dbg(VFS, "Negotiating Unix capabilities with the server failed. Consider mounting with the Unix Extensions disabled if problems are found by specifying the nounix mount option.\n");
3257
3258 }
3259 }
3260 }
3261 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3262
cifs_setup_cifs_sb(struct cifs_sb_info * cifs_sb)3263 int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
3264 {
3265 struct smb3_fs_context *ctx = cifs_sb->ctx;
3266
3267 INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
3268
3269 spin_lock_init(&cifs_sb->tlink_tree_lock);
3270 cifs_sb->tlink_tree = RB_ROOT;
3271
3272 cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n",
3273 ctx->file_mode, ctx->dir_mode);
3274
3275 /* this is needed for ASCII cp to Unicode converts */
3276 if (ctx->iocharset == NULL) {
3277 /* load_nls_default cannot return null */
3278 cifs_sb->local_nls = load_nls_default();
3279 } else {
3280 cifs_sb->local_nls = load_nls(ctx->iocharset);
3281 if (cifs_sb->local_nls == NULL) {
3282 cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
3283 ctx->iocharset);
3284 return -ELIBACC;
3285 }
3286 }
3287 ctx->local_nls = cifs_sb->local_nls;
3288
3289 smb3_update_mnt_flags(cifs_sb);
3290
3291 if (ctx->direct_io)
3292 cifs_dbg(FYI, "mounting share using direct i/o\n");
3293 if (ctx->cache_ro) {
3294 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
3295 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
3296 } else if (ctx->cache_rw) {
3297 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
3298 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
3299 CIFS_MOUNT_RW_CACHE);
3300 }
3301
3302 if ((ctx->cifs_acl) && (ctx->dynperm))
3303 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
3304
3305 if (ctx->prepath) {
3306 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
3307 if (cifs_sb->prepath == NULL)
3308 return -ENOMEM;
3309 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3310 }
3311
3312 return 0;
3313 }
3314
3315 /* Release all succeed connections */
cifs_mount_put_conns(struct cifs_mount_ctx * mnt_ctx)3316 void cifs_mount_put_conns(struct cifs_mount_ctx *mnt_ctx)
3317 {
3318 int rc = 0;
3319
3320 if (mnt_ctx->tcon)
3321 cifs_put_tcon(mnt_ctx->tcon);
3322 else if (mnt_ctx->ses)
3323 cifs_put_smb_ses(mnt_ctx->ses);
3324 else if (mnt_ctx->server)
3325 cifs_put_tcp_session(mnt_ctx->server, 0);
3326 mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
3327 free_xid(mnt_ctx->xid);
3328 }
3329
cifs_mount_get_session(struct cifs_mount_ctx * mnt_ctx)3330 int cifs_mount_get_session(struct cifs_mount_ctx *mnt_ctx)
3331 {
3332 struct TCP_Server_Info *server = NULL;
3333 struct smb3_fs_context *ctx;
3334 struct cifs_ses *ses = NULL;
3335 unsigned int xid;
3336 int rc = 0;
3337
3338 xid = get_xid();
3339
3340 if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->fs_ctx)) {
3341 rc = -EINVAL;
3342 goto out;
3343 }
3344 ctx = mnt_ctx->fs_ctx;
3345
3346 /* get a reference to a tcp session */
3347 server = cifs_get_tcp_session(ctx, NULL);
3348 if (IS_ERR(server)) {
3349 rc = PTR_ERR(server);
3350 server = NULL;
3351 goto out;
3352 }
3353
3354 /* get a reference to a SMB session */
3355 ses = cifs_get_smb_ses(server, ctx);
3356 if (IS_ERR(ses)) {
3357 rc = PTR_ERR(ses);
3358 ses = NULL;
3359 goto out;
3360 }
3361
3362 if ((ctx->persistent == true) && (!(ses->server->capabilities &
3363 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
3364 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
3365 rc = -EOPNOTSUPP;
3366 }
3367
3368 out:
3369 mnt_ctx->xid = xid;
3370 mnt_ctx->server = server;
3371 mnt_ctx->ses = ses;
3372 mnt_ctx->tcon = NULL;
3373
3374 return rc;
3375 }
3376
cifs_mount_get_tcon(struct cifs_mount_ctx * mnt_ctx)3377 int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx)
3378 {
3379 struct TCP_Server_Info *server;
3380 struct cifs_sb_info *cifs_sb;
3381 struct smb3_fs_context *ctx;
3382 struct cifs_tcon *tcon = NULL;
3383 int rc = 0;
3384
3385 if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->server || !mnt_ctx->ses || !mnt_ctx->fs_ctx ||
3386 !mnt_ctx->cifs_sb)) {
3387 rc = -EINVAL;
3388 goto out;
3389 }
3390 server = mnt_ctx->server;
3391 ctx = mnt_ctx->fs_ctx;
3392 cifs_sb = mnt_ctx->cifs_sb;
3393
3394 /* search for existing tcon to this server share */
3395 tcon = cifs_get_tcon(mnt_ctx->ses, ctx);
3396 if (IS_ERR(tcon)) {
3397 rc = PTR_ERR(tcon);
3398 tcon = NULL;
3399 goto out;
3400 }
3401
3402 /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
3403 if (tcon->posix_extensions)
3404 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
3405
3406 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3407 /* tell server which Unix caps we support */
3408 if (cap_unix(tcon->ses)) {
3409 /*
3410 * reset of caps checks mount to see if unix extensions disabled
3411 * for just this mount.
3412 */
3413 reset_cifs_unix_caps(mnt_ctx->xid, tcon, cifs_sb, ctx);
3414 spin_lock(&tcon->ses->server->srv_lock);
3415 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
3416 (le64_to_cpu(tcon->fsUnixInfo.Capability) &
3417 CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
3418 spin_unlock(&tcon->ses->server->srv_lock);
3419 rc = -EACCES;
3420 goto out;
3421 }
3422 spin_unlock(&tcon->ses->server->srv_lock);
3423 } else
3424 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3425 tcon->unix_ext = 0; /* server does not support them */
3426
3427 /* do not care if a following call succeed - informational */
3428 if (!tcon->pipe && server->ops->qfs_tcon) {
3429 server->ops->qfs_tcon(mnt_ctx->xid, tcon, cifs_sb);
3430 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
3431 if (tcon->fsDevInfo.DeviceCharacteristics &
3432 cpu_to_le32(FILE_READ_ONLY_DEVICE))
3433 cifs_dbg(VFS, "mounted to read only share\n");
3434 else if ((cifs_sb->mnt_cifs_flags &
3435 CIFS_MOUNT_RW_CACHE) == 0)
3436 cifs_dbg(VFS, "read only mount of RW share\n");
3437 /* no need to log a RW mount of a typical RW share */
3438 }
3439 }
3440
3441 /*
3442 * Clamp the rsize/wsize mount arguments if they are too big for the server
3443 * and set the rsize/wsize to the negotiated values if not passed in by
3444 * the user on mount
3445 */
3446 if ((cifs_sb->ctx->wsize == 0) ||
3447 (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx))) {
3448 cifs_sb->ctx->wsize =
3449 round_down(server->ops->negotiate_wsize(tcon, ctx), PAGE_SIZE);
3450 /*
3451 * in the very unlikely event that the server sent a max write size under PAGE_SIZE,
3452 * (which would get rounded down to 0) then reset wsize to absolute minimum eg 4096
3453 */
3454 if (cifs_sb->ctx->wsize == 0) {
3455 cifs_sb->ctx->wsize = PAGE_SIZE;
3456 cifs_dbg(VFS, "wsize too small, reset to minimum ie PAGE_SIZE, usually 4096\n");
3457 }
3458 }
3459 if ((cifs_sb->ctx->rsize == 0) ||
3460 (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
3461 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
3462
3463 /*
3464 * The cookie is initialized from volume info returned above.
3465 * Inside cifs_fscache_get_super_cookie it checks
3466 * that we do not get super cookie twice.
3467 */
3468 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
3469 cifs_fscache_get_super_cookie(tcon);
3470
3471 out:
3472 mnt_ctx->tcon = tcon;
3473 return rc;
3474 }
3475
mount_setup_tlink(struct cifs_sb_info * cifs_sb,struct cifs_ses * ses,struct cifs_tcon * tcon)3476 static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
3477 struct cifs_tcon *tcon)
3478 {
3479 struct tcon_link *tlink;
3480
3481 /* hang the tcon off of the superblock */
3482 tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
3483 if (tlink == NULL)
3484 return -ENOMEM;
3485
3486 tlink->tl_uid = ses->linux_uid;
3487 tlink->tl_tcon = tcon;
3488 tlink->tl_time = jiffies;
3489 set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
3490 set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3491
3492 cifs_sb->master_tlink = tlink;
3493 spin_lock(&cifs_sb->tlink_tree_lock);
3494 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
3495 spin_unlock(&cifs_sb->tlink_tree_lock);
3496
3497 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
3498 TLINK_IDLE_EXPIRE);
3499 return 0;
3500 }
3501
3502 static int
cifs_are_all_path_components_accessible(struct TCP_Server_Info * server,unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,char * full_path,int added_treename)3503 cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3504 unsigned int xid,
3505 struct cifs_tcon *tcon,
3506 struct cifs_sb_info *cifs_sb,
3507 char *full_path,
3508 int added_treename)
3509 {
3510 int rc;
3511 char *s;
3512 char sep, tmp;
3513 int skip = added_treename ? 1 : 0;
3514
3515 sep = CIFS_DIR_SEP(cifs_sb);
3516 s = full_path;
3517
3518 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3519 while (rc == 0) {
3520 /* skip separators */
3521 while (*s == sep)
3522 s++;
3523 if (!*s)
3524 break;
3525 /* next separator */
3526 while (*s && *s != sep)
3527 s++;
3528 /*
3529 * if the treename is added, we then have to skip the first
3530 * part within the separators
3531 */
3532 if (skip) {
3533 skip = 0;
3534 continue;
3535 }
3536 /*
3537 * temporarily null-terminate the path at the end of
3538 * the current component
3539 */
3540 tmp = *s;
3541 *s = 0;
3542 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3543 full_path);
3544 *s = tmp;
3545 }
3546 return rc;
3547 }
3548
3549 /*
3550 * Check if path is remote (i.e. a DFS share).
3551 *
3552 * Return -EREMOTE if it is, otherwise 0 or -errno.
3553 */
cifs_is_path_remote(struct cifs_mount_ctx * mnt_ctx)3554 int cifs_is_path_remote(struct cifs_mount_ctx *mnt_ctx)
3555 {
3556 int rc;
3557 struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
3558 struct TCP_Server_Info *server = mnt_ctx->server;
3559 unsigned int xid = mnt_ctx->xid;
3560 struct cifs_tcon *tcon = mnt_ctx->tcon;
3561 struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
3562 char *full_path;
3563
3564 if (!server->ops->is_path_accessible)
3565 return -EOPNOTSUPP;
3566
3567 /*
3568 * cifs_build_path_to_root works only when we have a valid tcon
3569 */
3570 full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3571 tcon->Flags & SMB_SHARE_IS_IN_DFS);
3572 if (full_path == NULL)
3573 return -ENOMEM;
3574
3575 cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3576
3577 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3578 full_path);
3579 if (rc != 0 && rc != -EREMOTE)
3580 goto out;
3581
3582 if (rc != -EREMOTE) {
3583 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3584 cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3585 if (rc != 0) {
3586 cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3587 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3588 rc = 0;
3589 }
3590 }
3591
3592 out:
3593 kfree(full_path);
3594 return rc;
3595 }
3596
3597 #ifdef CONFIG_CIFS_DFS_UPCALL
cifs_mount(struct cifs_sb_info * cifs_sb,struct smb3_fs_context * ctx)3598 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3599 {
3600 struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3601 bool isdfs;
3602 int rc;
3603
3604 INIT_LIST_HEAD(&mnt_ctx.dfs_ses_list);
3605
3606 rc = dfs_mount_share(&mnt_ctx, &isdfs);
3607 if (rc)
3608 goto error;
3609 if (!isdfs)
3610 goto out;
3611
3612 /*
3613 * After reconnecting to a different server, unique ids won't match anymore, so we disable
3614 * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
3615 */
3616 cifs_autodisable_serverino(cifs_sb);
3617 /*
3618 * Force the use of prefix path to support failover on DFS paths that resolve to targets
3619 * that have different prefix paths.
3620 */
3621 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3622 kfree(cifs_sb->prepath);
3623 cifs_sb->prepath = ctx->prepath;
3624 ctx->prepath = NULL;
3625
3626 out:
3627 cifs_try_adding_channels(mnt_ctx.ses);
3628 rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3629 if (rc)
3630 goto error;
3631
3632 free_xid(mnt_ctx.xid);
3633 return rc;
3634
3635 error:
3636 dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
3637 cifs_mount_put_conns(&mnt_ctx);
3638 return rc;
3639 }
3640 #else
cifs_mount(struct cifs_sb_info * cifs_sb,struct smb3_fs_context * ctx)3641 int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3642 {
3643 int rc = 0;
3644 struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3645
3646 rc = cifs_mount_get_session(&mnt_ctx);
3647 if (rc)
3648 goto error;
3649
3650 rc = cifs_mount_get_tcon(&mnt_ctx);
3651 if (rc)
3652 goto error;
3653
3654 rc = cifs_is_path_remote(&mnt_ctx);
3655 if (rc == -EREMOTE)
3656 rc = -EOPNOTSUPP;
3657 if (rc)
3658 goto error;
3659
3660 rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3661 if (rc)
3662 goto error;
3663
3664 free_xid(mnt_ctx.xid);
3665 return rc;
3666
3667 error:
3668 cifs_mount_put_conns(&mnt_ctx);
3669 return rc;
3670 }
3671 #endif
3672
3673 /*
3674 * Issue a TREE_CONNECT request.
3675 */
3676 int
CIFSTCon(const unsigned int xid,struct cifs_ses * ses,const char * tree,struct cifs_tcon * tcon,const struct nls_table * nls_codepage)3677 CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3678 const char *tree, struct cifs_tcon *tcon,
3679 const struct nls_table *nls_codepage)
3680 {
3681 struct smb_hdr *smb_buffer;
3682 struct smb_hdr *smb_buffer_response;
3683 TCONX_REQ *pSMB;
3684 TCONX_RSP *pSMBr;
3685 unsigned char *bcc_ptr;
3686 int rc = 0;
3687 int length;
3688 __u16 bytes_left, count;
3689
3690 if (ses == NULL)
3691 return -EIO;
3692
3693 smb_buffer = cifs_buf_get();
3694 if (smb_buffer == NULL)
3695 return -ENOMEM;
3696
3697 smb_buffer_response = smb_buffer;
3698
3699 header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3700 NULL /*no tid */, 4 /*wct */);
3701
3702 smb_buffer->Mid = get_next_mid(ses->server);
3703 smb_buffer->Uid = ses->Suid;
3704 pSMB = (TCONX_REQ *) smb_buffer;
3705 pSMBr = (TCONX_RSP *) smb_buffer_response;
3706
3707 pSMB->AndXCommand = 0xFF;
3708 pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3709 bcc_ptr = &pSMB->Password[0];
3710
3711 pSMB->PasswordLength = cpu_to_le16(1); /* minimum */
3712 *bcc_ptr = 0; /* password is null byte */
3713 bcc_ptr++; /* skip password */
3714 /* already aligned so no need to do it below */
3715
3716 if (ses->server->sign)
3717 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3718
3719 if (ses->capabilities & CAP_STATUS32)
3720 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3721
3722 if (ses->capabilities & CAP_DFS)
3723 smb_buffer->Flags2 |= SMBFLG2_DFS;
3724
3725 if (ses->capabilities & CAP_UNICODE) {
3726 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3727 length =
3728 cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3729 6 /* max utf8 char length in bytes */ *
3730 (/* server len*/ + 256 /* share len */), nls_codepage);
3731 bcc_ptr += 2 * length; /* convert num 16 bit words to bytes */
3732 bcc_ptr += 2; /* skip trailing null */
3733 } else { /* ASCII */
3734 strcpy(bcc_ptr, tree);
3735 bcc_ptr += strlen(tree) + 1;
3736 }
3737 strcpy(bcc_ptr, "?????");
3738 bcc_ptr += strlen("?????");
3739 bcc_ptr += 1;
3740 count = bcc_ptr - &pSMB->Password[0];
3741 be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3742 pSMB->ByteCount = cpu_to_le16(count);
3743
3744 rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3745 0);
3746
3747 /* above now done in SendReceive */
3748 if (rc == 0) {
3749 bool is_unicode;
3750
3751 tcon->tid = smb_buffer_response->Tid;
3752 bcc_ptr = pByteArea(smb_buffer_response);
3753 bytes_left = get_bcc(smb_buffer_response);
3754 length = strnlen(bcc_ptr, bytes_left - 2);
3755 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3756 is_unicode = true;
3757 else
3758 is_unicode = false;
3759
3760
3761 /* skip service field (NB: this field is always ASCII) */
3762 if (length == 3) {
3763 if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3764 (bcc_ptr[2] == 'C')) {
3765 cifs_dbg(FYI, "IPC connection\n");
3766 tcon->ipc = true;
3767 tcon->pipe = true;
3768 }
3769 } else if (length == 2) {
3770 if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3771 /* the most common case */
3772 cifs_dbg(FYI, "disk share connection\n");
3773 }
3774 }
3775 bcc_ptr += length + 1;
3776 bytes_left -= (length + 1);
3777 strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
3778
3779 /* mostly informational -- no need to fail on error here */
3780 kfree(tcon->nativeFileSystem);
3781 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3782 bytes_left, is_unicode,
3783 nls_codepage);
3784
3785 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3786
3787 if ((smb_buffer_response->WordCount == 3) ||
3788 (smb_buffer_response->WordCount == 7))
3789 /* field is in same location */
3790 tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3791 else
3792 tcon->Flags = 0;
3793 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3794 }
3795
3796 cifs_buf_release(smb_buffer);
3797 return rc;
3798 }
3799
delayed_free(struct rcu_head * p)3800 static void delayed_free(struct rcu_head *p)
3801 {
3802 struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3803
3804 unload_nls(cifs_sb->local_nls);
3805 smb3_cleanup_fs_context(cifs_sb->ctx);
3806 kfree(cifs_sb);
3807 }
3808
3809 void
cifs_umount(struct cifs_sb_info * cifs_sb)3810 cifs_umount(struct cifs_sb_info *cifs_sb)
3811 {
3812 struct rb_root *root = &cifs_sb->tlink_tree;
3813 struct rb_node *node;
3814 struct tcon_link *tlink;
3815
3816 cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3817
3818 spin_lock(&cifs_sb->tlink_tree_lock);
3819 while ((node = rb_first(root))) {
3820 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3821 cifs_get_tlink(tlink);
3822 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3823 rb_erase(node, root);
3824
3825 spin_unlock(&cifs_sb->tlink_tree_lock);
3826 cifs_put_tlink(tlink);
3827 spin_lock(&cifs_sb->tlink_tree_lock);
3828 }
3829 spin_unlock(&cifs_sb->tlink_tree_lock);
3830
3831 kfree(cifs_sb->prepath);
3832 call_rcu(&cifs_sb->rcu, delayed_free);
3833 }
3834
3835 int
cifs_negotiate_protocol(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server)3836 cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
3837 struct TCP_Server_Info *server)
3838 {
3839 int rc = 0;
3840
3841 if (!server->ops->need_neg || !server->ops->negotiate)
3842 return -ENOSYS;
3843
3844 /* only send once per connect */
3845 spin_lock(&server->srv_lock);
3846 if (server->tcpStatus != CifsGood &&
3847 server->tcpStatus != CifsNew &&
3848 server->tcpStatus != CifsNeedNegotiate) {
3849 spin_unlock(&server->srv_lock);
3850 return -EHOSTDOWN;
3851 }
3852
3853 if (!server->ops->need_neg(server) &&
3854 server->tcpStatus == CifsGood) {
3855 spin_unlock(&server->srv_lock);
3856 return 0;
3857 }
3858
3859 server->tcpStatus = CifsInNegotiate;
3860 spin_unlock(&server->srv_lock);
3861
3862 rc = server->ops->negotiate(xid, ses, server);
3863 if (rc == 0) {
3864 spin_lock(&server->srv_lock);
3865 if (server->tcpStatus == CifsInNegotiate)
3866 server->tcpStatus = CifsGood;
3867 else
3868 rc = -EHOSTDOWN;
3869 spin_unlock(&server->srv_lock);
3870 } else {
3871 spin_lock(&server->srv_lock);
3872 if (server->tcpStatus == CifsInNegotiate)
3873 server->tcpStatus = CifsNeedNegotiate;
3874 spin_unlock(&server->srv_lock);
3875 }
3876
3877 return rc;
3878 }
3879
3880 int
cifs_setup_session(const unsigned int xid,struct cifs_ses * ses,struct TCP_Server_Info * server,struct nls_table * nls_info)3881 cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3882 struct TCP_Server_Info *server,
3883 struct nls_table *nls_info)
3884 {
3885 int rc = -ENOSYS;
3886 struct TCP_Server_Info *pserver = SERVER_IS_CHAN(server) ? server->primary_server : server;
3887 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&pserver->dstaddr;
3888 struct sockaddr_in *addr = (struct sockaddr_in *)&pserver->dstaddr;
3889 bool is_binding = false;
3890
3891 spin_lock(&ses->ses_lock);
3892 cifs_dbg(FYI, "%s: channel connect bitmap: 0x%lx\n",
3893 __func__, ses->chans_need_reconnect);
3894
3895 if (ses->ses_status != SES_GOOD &&
3896 ses->ses_status != SES_NEW &&
3897 ses->ses_status != SES_NEED_RECON) {
3898 spin_unlock(&ses->ses_lock);
3899 return -EHOSTDOWN;
3900 }
3901
3902 /* only send once per connect */
3903 spin_lock(&ses->chan_lock);
3904 if (CIFS_ALL_CHANS_GOOD(ses)) {
3905 if (ses->ses_status == SES_NEED_RECON)
3906 ses->ses_status = SES_GOOD;
3907 spin_unlock(&ses->chan_lock);
3908 spin_unlock(&ses->ses_lock);
3909 return 0;
3910 }
3911
3912 cifs_chan_set_in_reconnect(ses, server);
3913 is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
3914 spin_unlock(&ses->chan_lock);
3915
3916 if (!is_binding) {
3917 ses->ses_status = SES_IN_SETUP;
3918
3919 /* force iface_list refresh */
3920 ses->iface_last_update = 0;
3921 }
3922 spin_unlock(&ses->ses_lock);
3923
3924 /* update ses ip_addr only for primary chan */
3925 if (server == pserver) {
3926 if (server->dstaddr.ss_family == AF_INET6)
3927 scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
3928 else
3929 scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
3930 }
3931
3932 if (!is_binding) {
3933 ses->capabilities = server->capabilities;
3934 if (!linuxExtEnabled)
3935 ses->capabilities &= (~server->vals->cap_unix);
3936
3937 if (ses->auth_key.response) {
3938 cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3939 ses->auth_key.response);
3940 kfree_sensitive(ses->auth_key.response);
3941 ses->auth_key.response = NULL;
3942 ses->auth_key.len = 0;
3943 }
3944 }
3945
3946 cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3947 server->sec_mode, server->capabilities, server->timeAdj);
3948
3949 if (server->ops->sess_setup)
3950 rc = server->ops->sess_setup(xid, ses, server, nls_info);
3951
3952 if (rc) {
3953 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3954 spin_lock(&ses->ses_lock);
3955 if (ses->ses_status == SES_IN_SETUP)
3956 ses->ses_status = SES_NEED_RECON;
3957 spin_lock(&ses->chan_lock);
3958 cifs_chan_clear_in_reconnect(ses, server);
3959 spin_unlock(&ses->chan_lock);
3960 spin_unlock(&ses->ses_lock);
3961 } else {
3962 spin_lock(&ses->ses_lock);
3963 if (ses->ses_status == SES_IN_SETUP)
3964 ses->ses_status = SES_GOOD;
3965 spin_lock(&ses->chan_lock);
3966 cifs_chan_clear_in_reconnect(ses, server);
3967 cifs_chan_clear_need_reconnect(ses, server);
3968 spin_unlock(&ses->chan_lock);
3969 spin_unlock(&ses->ses_lock);
3970 }
3971
3972 return rc;
3973 }
3974
3975 static int
cifs_set_vol_auth(struct smb3_fs_context * ctx,struct cifs_ses * ses)3976 cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3977 {
3978 ctx->sectype = ses->sectype;
3979
3980 /* krb5 is special, since we don't need username or pw */
3981 if (ctx->sectype == Kerberos)
3982 return 0;
3983
3984 return cifs_set_cifscreds(ctx, ses);
3985 }
3986
3987 static struct cifs_tcon *
cifs_construct_tcon(struct cifs_sb_info * cifs_sb,kuid_t fsuid)3988 cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3989 {
3990 int rc;
3991 struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3992 struct cifs_ses *ses;
3993 struct cifs_tcon *tcon = NULL;
3994 struct smb3_fs_context *ctx;
3995
3996 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3997 if (ctx == NULL)
3998 return ERR_PTR(-ENOMEM);
3999
4000 ctx->local_nls = cifs_sb->local_nls;
4001 ctx->linux_uid = fsuid;
4002 ctx->cred_uid = fsuid;
4003 ctx->UNC = master_tcon->tree_name;
4004 ctx->retry = master_tcon->retry;
4005 ctx->nocase = master_tcon->nocase;
4006 ctx->nohandlecache = master_tcon->nohandlecache;
4007 ctx->local_lease = master_tcon->local_lease;
4008 ctx->no_lease = master_tcon->no_lease;
4009 ctx->resilient = master_tcon->use_resilient;
4010 ctx->persistent = master_tcon->use_persistent;
4011 ctx->handle_timeout = master_tcon->handle_timeout;
4012 ctx->no_linux_ext = !master_tcon->unix_ext;
4013 ctx->linux_ext = master_tcon->posix_extensions;
4014 ctx->sectype = master_tcon->ses->sectype;
4015 ctx->sign = master_tcon->ses->sign;
4016 ctx->seal = master_tcon->seal;
4017 ctx->witness = master_tcon->use_witness;
4018
4019 rc = cifs_set_vol_auth(ctx, master_tcon->ses);
4020 if (rc) {
4021 tcon = ERR_PTR(rc);
4022 goto out;
4023 }
4024
4025 /* get a reference for the same TCP session */
4026 spin_lock(&cifs_tcp_ses_lock);
4027 ++master_tcon->ses->server->srv_count;
4028 spin_unlock(&cifs_tcp_ses_lock);
4029
4030 ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
4031 if (IS_ERR(ses)) {
4032 tcon = (struct cifs_tcon *)ses;
4033 cifs_put_tcp_session(master_tcon->ses->server, 0);
4034 goto out;
4035 }
4036
4037 tcon = cifs_get_tcon(ses, ctx);
4038 if (IS_ERR(tcon)) {
4039 cifs_put_smb_ses(ses);
4040 goto out;
4041 }
4042
4043 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
4044 if (cap_unix(ses))
4045 reset_cifs_unix_caps(0, tcon, NULL, ctx);
4046 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
4047
4048 out:
4049 kfree(ctx->username);
4050 kfree_sensitive(ctx->password);
4051 kfree(ctx);
4052
4053 return tcon;
4054 }
4055
4056 struct cifs_tcon *
cifs_sb_master_tcon(struct cifs_sb_info * cifs_sb)4057 cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
4058 {
4059 return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
4060 }
4061
4062 /* find and return a tlink with given uid */
4063 static struct tcon_link *
tlink_rb_search(struct rb_root * root,kuid_t uid)4064 tlink_rb_search(struct rb_root *root, kuid_t uid)
4065 {
4066 struct rb_node *node = root->rb_node;
4067 struct tcon_link *tlink;
4068
4069 while (node) {
4070 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
4071
4072 if (uid_gt(tlink->tl_uid, uid))
4073 node = node->rb_left;
4074 else if (uid_lt(tlink->tl_uid, uid))
4075 node = node->rb_right;
4076 else
4077 return tlink;
4078 }
4079 return NULL;
4080 }
4081
4082 /* insert a tcon_link into the tree */
4083 static void
tlink_rb_insert(struct rb_root * root,struct tcon_link * new_tlink)4084 tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
4085 {
4086 struct rb_node **new = &(root->rb_node), *parent = NULL;
4087 struct tcon_link *tlink;
4088
4089 while (*new) {
4090 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
4091 parent = *new;
4092
4093 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
4094 new = &((*new)->rb_left);
4095 else
4096 new = &((*new)->rb_right);
4097 }
4098
4099 rb_link_node(&new_tlink->tl_rbnode, parent, new);
4100 rb_insert_color(&new_tlink->tl_rbnode, root);
4101 }
4102
4103 /*
4104 * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4105 * current task.
4106 *
4107 * If the superblock doesn't refer to a multiuser mount, then just return
4108 * the master tcon for the mount.
4109 *
4110 * First, search the rbtree for an existing tcon for this fsuid. If one
4111 * exists, then check to see if it's pending construction. If it is then wait
4112 * for construction to complete. Once it's no longer pending, check to see if
4113 * it failed and either return an error or retry construction, depending on
4114 * the timeout.
4115 *
4116 * If one doesn't exist then insert a new tcon_link struct into the tree and
4117 * try to construct a new one.
4118 */
4119 struct tcon_link *
cifs_sb_tlink(struct cifs_sb_info * cifs_sb)4120 cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4121 {
4122 int ret;
4123 kuid_t fsuid = current_fsuid();
4124 struct tcon_link *tlink, *newtlink;
4125
4126 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4127 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4128
4129 spin_lock(&cifs_sb->tlink_tree_lock);
4130 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4131 if (tlink)
4132 cifs_get_tlink(tlink);
4133 spin_unlock(&cifs_sb->tlink_tree_lock);
4134
4135 if (tlink == NULL) {
4136 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4137 if (newtlink == NULL)
4138 return ERR_PTR(-ENOMEM);
4139 newtlink->tl_uid = fsuid;
4140 newtlink->tl_tcon = ERR_PTR(-EACCES);
4141 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4142 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4143 cifs_get_tlink(newtlink);
4144
4145 spin_lock(&cifs_sb->tlink_tree_lock);
4146 /* was one inserted after previous search? */
4147 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4148 if (tlink) {
4149 cifs_get_tlink(tlink);
4150 spin_unlock(&cifs_sb->tlink_tree_lock);
4151 kfree(newtlink);
4152 goto wait_for_construction;
4153 }
4154 tlink = newtlink;
4155 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4156 spin_unlock(&cifs_sb->tlink_tree_lock);
4157 } else {
4158 wait_for_construction:
4159 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4160 TASK_INTERRUPTIBLE);
4161 if (ret) {
4162 cifs_put_tlink(tlink);
4163 return ERR_PTR(-ERESTARTSYS);
4164 }
4165
4166 /* if it's good, return it */
4167 if (!IS_ERR(tlink->tl_tcon))
4168 return tlink;
4169
4170 /* return error if we tried this already recently */
4171 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4172 cifs_put_tlink(tlink);
4173 return ERR_PTR(-EACCES);
4174 }
4175
4176 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4177 goto wait_for_construction;
4178 }
4179
4180 tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4181 clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4182 wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4183
4184 if (IS_ERR(tlink->tl_tcon)) {
4185 cifs_put_tlink(tlink);
4186 return ERR_PTR(-EACCES);
4187 }
4188
4189 return tlink;
4190 }
4191
4192 /*
4193 * periodic workqueue job that scans tcon_tree for a superblock and closes
4194 * out tcons.
4195 */
4196 static void
cifs_prune_tlinks(struct work_struct * work)4197 cifs_prune_tlinks(struct work_struct *work)
4198 {
4199 struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4200 prune_tlinks.work);
4201 struct rb_root *root = &cifs_sb->tlink_tree;
4202 struct rb_node *node;
4203 struct rb_node *tmp;
4204 struct tcon_link *tlink;
4205
4206 /*
4207 * Because we drop the spinlock in the loop in order to put the tlink
4208 * it's not guarded against removal of links from the tree. The only
4209 * places that remove entries from the tree are this function and
4210 * umounts. Because this function is non-reentrant and is canceled
4211 * before umount can proceed, this is safe.
4212 */
4213 spin_lock(&cifs_sb->tlink_tree_lock);
4214 node = rb_first(root);
4215 while (node != NULL) {
4216 tmp = node;
4217 node = rb_next(tmp);
4218 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4219
4220 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4221 atomic_read(&tlink->tl_count) != 0 ||
4222 time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4223 continue;
4224
4225 cifs_get_tlink(tlink);
4226 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4227 rb_erase(tmp, root);
4228
4229 spin_unlock(&cifs_sb->tlink_tree_lock);
4230 cifs_put_tlink(tlink);
4231 spin_lock(&cifs_sb->tlink_tree_lock);
4232 }
4233 spin_unlock(&cifs_sb->tlink_tree_lock);
4234
4235 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4236 TLINK_IDLE_EXPIRE);
4237 }
4238
4239 #ifndef CONFIG_CIFS_DFS_UPCALL
cifs_tree_connect(const unsigned int xid,struct cifs_tcon * tcon,const struct nls_table * nlsc)4240 int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4241 {
4242 int rc;
4243 const struct smb_version_operations *ops = tcon->ses->server->ops;
4244
4245 /* only send once per connect */
4246 spin_lock(&tcon->tc_lock);
4247
4248 /* if tcon is marked for needing reconnect, update state */
4249 if (tcon->need_reconnect)
4250 tcon->status = TID_NEED_TCON;
4251
4252 if (tcon->status == TID_GOOD) {
4253 spin_unlock(&tcon->tc_lock);
4254 return 0;
4255 }
4256
4257 if (tcon->status != TID_NEW &&
4258 tcon->status != TID_NEED_TCON) {
4259 spin_unlock(&tcon->tc_lock);
4260 return -EHOSTDOWN;
4261 }
4262
4263 tcon->status = TID_IN_TCON;
4264 spin_unlock(&tcon->tc_lock);
4265
4266 rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
4267 if (rc) {
4268 spin_lock(&tcon->tc_lock);
4269 if (tcon->status == TID_IN_TCON)
4270 tcon->status = TID_NEED_TCON;
4271 spin_unlock(&tcon->tc_lock);
4272 } else {
4273 spin_lock(&tcon->tc_lock);
4274 if (tcon->status == TID_IN_TCON)
4275 tcon->status = TID_GOOD;
4276 tcon->need_reconnect = false;
4277 spin_unlock(&tcon->tc_lock);
4278 }
4279
4280 return rc;
4281 }
4282 #endif
4283