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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
55extern mempool_t *cifs_req_poolp;
56extern 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 NUM_STATUS_IO_TIMEOUT 5
64
65static int ip_connect(struct TCP_Server_Info *server);
66static int generic_ip_connect(struct TCP_Server_Info *server);
67static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
68static 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 */
76static 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 time64_t expiry, now;
83 unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;
84
85 if (!server->hostname)
86 return -EINVAL;
87
88 /* if server hostname isn't populated, there's nothing to do here */
89 if (server->hostname[0] == '\0')
90 return 0;
91
92 len = strlen(server->hostname) + 3;
93
94 unc = kmalloc(len, GFP_KERNEL);
95 if (!unc) {
96 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
97 return -ENOMEM;
98 }
99 scnprintf(unc, len, "\\\\%s", server->hostname);
100
101 spin_lock(&server->srv_lock);
102 ss = server->dstaddr;
103 spin_unlock(&server->srv_lock);
104
105 rc = dns_resolve_server_name_to_ip(unc, (struct sockaddr *)&ss, &expiry);
106 kfree(unc);
107
108 if (rc < 0) {
109 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
110 __func__, server->hostname, rc);
111 goto requeue_resolve;
112 }
113
114 spin_lock(&server->srv_lock);
115 memcpy(&server->dstaddr, &ss, sizeof(server->dstaddr));
116 spin_unlock(&server->srv_lock);
117
118 now = ktime_get_real_seconds();
119 if (expiry && expiry > now)
120 /* To make sure we don't use the cached entry, retry 1s */
121 ttl = max_t(unsigned long, expiry - now, SMB_DNS_RESOLVE_INTERVAL_MIN) + 1;
122
123requeue_resolve:
124 cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
125 __func__, ttl);
126 mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));
127
128 return rc;
129}
130
131static void smb2_query_server_interfaces(struct work_struct *work)
132{
133 int rc;
134 struct cifs_tcon *tcon = container_of(work,
135 struct cifs_tcon,
136 query_interfaces.work);
137
138 /*
139 * query server network interfaces, in case they change
140 */
141 rc = SMB3_request_interfaces(0, tcon, false);
142 if (rc) {
143 cifs_dbg(FYI, "%s: failed to query server interfaces: %d\n",
144 __func__, rc);
145 }
146
147 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
148 (SMB_INTERFACE_POLL_INTERVAL * HZ));
149}
150
151static void cifs_resolve_server(struct work_struct *work)
152{
153 int rc;
154 struct TCP_Server_Info *server = container_of(work,
155 struct TCP_Server_Info, resolve.work);
156
157 cifs_server_lock(server);
158
159 /*
160 * Resolve the hostname again to make sure that IP address is up-to-date.
161 */
162 rc = reconn_set_ipaddr_from_hostname(server);
163 if (rc) {
164 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
165 __func__, rc);
166 }
167
168 cifs_server_unlock(server);
169}
170
171/*
172 * Update the tcpStatus for the server.
173 * This is used to signal the cifsd thread to call cifs_reconnect
174 * ONLY cifsd thread should call cifs_reconnect. For any other
175 * thread, use this function
176 *
177 * @server: the tcp ses for which reconnect is needed
178 * @all_channels: if this needs to be done for all channels
179 */
180void
181cifs_signal_cifsd_for_reconnect(struct TCP_Server_Info *server,
182 bool all_channels)
183{
184 struct TCP_Server_Info *pserver;
185 struct cifs_ses *ses;
186 int i;
187
188 /* If server is a channel, select the primary channel */
189 pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
190
191 spin_lock(&pserver->srv_lock);
192 if (!all_channels) {
193 pserver->tcpStatus = CifsNeedReconnect;
194 spin_unlock(&pserver->srv_lock);
195 return;
196 }
197 spin_unlock(&pserver->srv_lock);
198
199 spin_lock(&cifs_tcp_ses_lock);
200 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
201 spin_lock(&ses->chan_lock);
202 for (i = 0; i < ses->chan_count; i++) {
203 spin_lock(&ses->chans[i].server->srv_lock);
204 ses->chans[i].server->tcpStatus = CifsNeedReconnect;
205 spin_unlock(&ses->chans[i].server->srv_lock);
206 }
207 spin_unlock(&ses->chan_lock);
208 }
209 spin_unlock(&cifs_tcp_ses_lock);
210}
211
212/*
213 * Mark all sessions and tcons for reconnect.
214 * IMPORTANT: make sure that this gets called only from
215 * cifsd thread. For any other thread, use
216 * cifs_signal_cifsd_for_reconnect
217 *
218 * @server: the tcp ses for which reconnect is needed
219 * @server needs to be previously set to CifsNeedReconnect.
220 * @mark_smb_session: whether even sessions need to be marked
221 */
222void
223cifs_mark_tcp_ses_conns_for_reconnect(struct TCP_Server_Info *server,
224 bool mark_smb_session)
225{
226 struct TCP_Server_Info *pserver;
227 struct cifs_ses *ses, *nses;
228 struct cifs_tcon *tcon;
229
230 /*
231 * before reconnecting the tcp session, mark the smb session (uid) and the tid bad so they
232 * are not used until reconnected.
233 */
234 cifs_dbg(FYI, "%s: marking necessary sessions and tcons for reconnect\n", __func__);
235
236 /* If server is a channel, select the primary channel */
237 pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
238
239
240 spin_lock(&cifs_tcp_ses_lock);
241 list_for_each_entry_safe(ses, nses, &pserver->smb_ses_list, smb_ses_list) {
242 /* check if iface is still active */
243 if (!cifs_chan_is_iface_active(ses, server))
244 cifs_chan_update_iface(ses, server);
245
246 spin_lock(&ses->chan_lock);
247 if (!mark_smb_session && cifs_chan_needs_reconnect(ses, server))
248 goto next_session;
249
250 if (mark_smb_session)
251 CIFS_SET_ALL_CHANS_NEED_RECONNECT(ses);
252 else
253 cifs_chan_set_need_reconnect(ses, server);
254
255 /* If all channels need reconnect, then tcon needs reconnect */
256 if (!mark_smb_session && !CIFS_ALL_CHANS_NEED_RECONNECT(ses))
257 goto next_session;
258
259 ses->ses_status = SES_NEED_RECON;
260
261 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
262 tcon->need_reconnect = true;
263 tcon->status = TID_NEED_RECON;
264 }
265 if (ses->tcon_ipc) {
266 ses->tcon_ipc->need_reconnect = true;
267 ses->tcon_ipc->status = TID_NEED_RECON;
268 }
269
270next_session:
271 spin_unlock(&ses->chan_lock);
272 }
273 spin_unlock(&cifs_tcp_ses_lock);
274}
275
276static void
277cifs_abort_connection(struct TCP_Server_Info *server)
278{
279 struct mid_q_entry *mid, *nmid;
280 struct list_head retry_list;
281
282 server->maxBuf = 0;
283 server->max_read = 0;
284
285 /* do not want to be sending data on a socket we are freeing */
286 cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
287 cifs_server_lock(server);
288 if (server->ssocket) {
289 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n", server->ssocket->state,
290 server->ssocket->flags);
291 kernel_sock_shutdown(server->ssocket, SHUT_WR);
292 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n", server->ssocket->state,
293 server->ssocket->flags);
294 sock_release(server->ssocket);
295 server->ssocket = NULL;
296 }
297 server->sequence_number = 0;
298 server->session_estab = false;
299 kfree_sensitive(server->session_key.response);
300 server->session_key.response = NULL;
301 server->session_key.len = 0;
302 server->lstrp = jiffies;
303
304 /* mark submitted MIDs for retry and issue callback */
305 INIT_LIST_HEAD(&retry_list);
306 cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
307 spin_lock(&server->mid_lock);
308 list_for_each_entry_safe(mid, nmid, &server->pending_mid_q, qhead) {
309 kref_get(&mid->refcount);
310 if (mid->mid_state == MID_REQUEST_SUBMITTED)
311 mid->mid_state = MID_RETRY_NEEDED;
312 list_move(&mid->qhead, &retry_list);
313 mid->mid_flags |= MID_DELETED;
314 }
315 spin_unlock(&server->mid_lock);
316 cifs_server_unlock(server);
317
318 cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
319 list_for_each_entry_safe(mid, nmid, &retry_list, qhead) {
320 list_del_init(&mid->qhead);
321 mid->callback(mid);
322 release_mid(mid);
323 }
324
325 if (cifs_rdma_enabled(server)) {
326 cifs_server_lock(server);
327 smbd_destroy(server);
328 cifs_server_unlock(server);
329 }
330}
331
332static bool cifs_tcp_ses_needs_reconnect(struct TCP_Server_Info *server, int num_targets)
333{
334 spin_lock(&server->srv_lock);
335 server->nr_targets = num_targets;
336 if (server->tcpStatus == CifsExiting) {
337 /* the demux thread will exit normally next time through the loop */
338 spin_unlock(&server->srv_lock);
339 wake_up(&server->response_q);
340 return false;
341 }
342
343 cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
344 trace_smb3_reconnect(server->CurrentMid, server->conn_id,
345 server->hostname);
346 server->tcpStatus = CifsNeedReconnect;
347
348 spin_unlock(&server->srv_lock);
349 return true;
350}
351
352/*
353 * cifs tcp session reconnection
354 *
355 * mark tcp session as reconnecting so temporarily locked
356 * mark all smb sessions as reconnecting for tcp session
357 * reconnect tcp session
358 * wake up waiters on reconnection? - (not needed currently)
359 *
360 * if mark_smb_session is passed as true, unconditionally mark
361 * the smb session (and tcon) for reconnect as well. This value
362 * doesn't really matter for non-multichannel scenario.
363 *
364 */
365static int __cifs_reconnect(struct TCP_Server_Info *server,
366 bool mark_smb_session)
367{
368 int rc = 0;
369
370 if (!cifs_tcp_ses_needs_reconnect(server, 1))
371 return 0;
372
373 cifs_mark_tcp_ses_conns_for_reconnect(server, mark_smb_session);
374
375 cifs_abort_connection(server);
376
377 do {
378 try_to_freeze();
379 cifs_server_lock(server);
380
381 if (!cifs_swn_set_server_dstaddr(server)) {
382 /* resolve the hostname again to make sure that IP address is up-to-date */
383 rc = reconn_set_ipaddr_from_hostname(server);
384 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
385 }
386
387 if (cifs_rdma_enabled(server))
388 rc = smbd_reconnect(server);
389 else
390 rc = generic_ip_connect(server);
391 if (rc) {
392 cifs_server_unlock(server);
393 cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
394 msleep(3000);
395 } else {
396 atomic_inc(&tcpSesReconnectCount);
397 set_credits(server, 1);
398 spin_lock(&server->srv_lock);
399 if (server->tcpStatus != CifsExiting)
400 server->tcpStatus = CifsNeedNegotiate;
401 spin_unlock(&server->srv_lock);
402 cifs_swn_reset_server_dstaddr(server);
403 cifs_server_unlock(server);
404 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
405 }
406 } while (server->tcpStatus == CifsNeedReconnect);
407
408 spin_lock(&server->srv_lock);
409 if (server->tcpStatus == CifsNeedNegotiate)
410 mod_delayed_work(cifsiod_wq, &server->echo, 0);
411 spin_unlock(&server->srv_lock);
412
413 wake_up(&server->response_q);
414 return rc;
415}
416
417#ifdef CONFIG_CIFS_DFS_UPCALL
418static int __reconnect_target_unlocked(struct TCP_Server_Info *server, const char *target)
419{
420 int rc;
421 char *hostname;
422
423 if (!cifs_swn_set_server_dstaddr(server)) {
424 if (server->hostname != target) {
425 hostname = extract_hostname(target);
426 if (!IS_ERR(hostname)) {
427 kfree(server->hostname);
428 server->hostname = hostname;
429 } else {
430 cifs_dbg(FYI, "%s: couldn't extract hostname or address from dfs target: %ld\n",
431 __func__, PTR_ERR(hostname));
432 cifs_dbg(FYI, "%s: default to last target server: %s\n", __func__,
433 server->hostname);
434 }
435 }
436 /* resolve the hostname again to make sure that IP address is up-to-date. */
437 rc = reconn_set_ipaddr_from_hostname(server);
438 cifs_dbg(FYI, "%s: reconn_set_ipaddr_from_hostname: rc=%d\n", __func__, rc);
439 }
440 /* Reconnect the socket */
441 if (cifs_rdma_enabled(server))
442 rc = smbd_reconnect(server);
443 else
444 rc = generic_ip_connect(server);
445
446 return rc;
447}
448
449static int reconnect_target_unlocked(struct TCP_Server_Info *server, struct dfs_cache_tgt_list *tl,
450 struct dfs_cache_tgt_iterator **target_hint)
451{
452 int rc;
453 struct dfs_cache_tgt_iterator *tit;
454
455 *target_hint = NULL;
456
457 /* If dfs target list is empty, then reconnect to last server */
458 tit = dfs_cache_get_tgt_iterator(tl);
459 if (!tit)
460 return __reconnect_target_unlocked(server, server->hostname);
461
462 /* Otherwise, try every dfs target in @tl */
463 for (; tit; tit = dfs_cache_get_next_tgt(tl, tit)) {
464 rc = __reconnect_target_unlocked(server, dfs_cache_get_tgt_name(tit));
465 if (!rc) {
466 *target_hint = tit;
467 break;
468 }
469 }
470 return rc;
471}
472
473static int reconnect_dfs_server(struct TCP_Server_Info *server)
474{
475 int rc = 0;
476 const char *refpath = server->current_fullpath + 1;
477 struct dfs_cache_tgt_list tl = DFS_CACHE_TGT_LIST_INIT(tl);
478 struct dfs_cache_tgt_iterator *target_hint = NULL;
479 int num_targets = 0;
480
481 /*
482 * Determine the number of dfs targets the referral path in @cifs_sb resolves to.
483 *
484 * smb2_reconnect() needs to know how long it should wait based upon the number of dfs
485 * targets (server->nr_targets). It's also possible that the cached referral was cleared
486 * through /proc/fs/cifs/dfscache or the target list is empty due to server settings after
487 * refreshing the referral, so, in this case, default it to 1.
488 */
489 if (!dfs_cache_noreq_find(refpath, NULL, &tl))
490 num_targets = dfs_cache_get_nr_tgts(&tl);
491 if (!num_targets)
492 num_targets = 1;
493
494 if (!cifs_tcp_ses_needs_reconnect(server, num_targets))
495 return 0;
496
497 /*
498 * Unconditionally mark all sessions & tcons for reconnect as we might be connecting to a
499 * different server or share during failover. It could be improved by adding some logic to
500 * only do that in case it connects to a different server or share, though.
501 */
502 cifs_mark_tcp_ses_conns_for_reconnect(server, true);
503
504 cifs_abort_connection(server);
505
506 do {
507 try_to_freeze();
508 cifs_server_lock(server);
509
510 rc = reconnect_target_unlocked(server, &tl, &target_hint);
511 if (rc) {
512 /* Failed to reconnect socket */
513 cifs_server_unlock(server);
514 cifs_dbg(FYI, "%s: reconnect error %d\n", __func__, rc);
515 msleep(3000);
516 continue;
517 }
518 /*
519 * Socket was created. Update tcp session status to CifsNeedNegotiate so that a
520 * process waiting for reconnect will know it needs to re-establish session and tcon
521 * through the reconnected target server.
522 */
523 atomic_inc(&tcpSesReconnectCount);
524 set_credits(server, 1);
525 spin_lock(&server->srv_lock);
526 if (server->tcpStatus != CifsExiting)
527 server->tcpStatus = CifsNeedNegotiate;
528 spin_unlock(&server->srv_lock);
529 cifs_swn_reset_server_dstaddr(server);
530 cifs_server_unlock(server);
531 mod_delayed_work(cifsiod_wq, &server->reconnect, 0);
532 } while (server->tcpStatus == CifsNeedReconnect);
533
534 dfs_cache_noreq_update_tgthint(refpath, target_hint);
535 dfs_cache_free_tgts(&tl);
536
537 /* Need to set up echo worker again once connection has been established */
538 spin_lock(&server->srv_lock);
539 if (server->tcpStatus == CifsNeedNegotiate)
540 mod_delayed_work(cifsiod_wq, &server->echo, 0);
541 spin_unlock(&server->srv_lock);
542
543 wake_up(&server->response_q);
544 return rc;
545}
546
547int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
548{
549 mutex_lock(&server->refpath_lock);
550 if (!server->leaf_fullpath) {
551 mutex_unlock(&server->refpath_lock);
552 return __cifs_reconnect(server, mark_smb_session);
553 }
554 mutex_unlock(&server->refpath_lock);
555
556 return reconnect_dfs_server(server);
557}
558#else
559int cifs_reconnect(struct TCP_Server_Info *server, bool mark_smb_session)
560{
561 return __cifs_reconnect(server, mark_smb_session);
562}
563#endif
564
565static void
566cifs_echo_request(struct work_struct *work)
567{
568 int rc;
569 struct TCP_Server_Info *server = container_of(work,
570 struct TCP_Server_Info, echo.work);
571
572 /*
573 * We cannot send an echo if it is disabled.
574 * Also, no need to ping if we got a response recently.
575 */
576
577 if (server->tcpStatus == CifsNeedReconnect ||
578 server->tcpStatus == CifsExiting ||
579 server->tcpStatus == CifsNew ||
580 (server->ops->can_echo && !server->ops->can_echo(server)) ||
581 time_before(jiffies, server->lstrp + server->echo_interval - HZ))
582 goto requeue_echo;
583
584 rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
585 if (rc)
586 cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
587 server->hostname);
588
589 /* Check witness registrations */
590 cifs_swn_check();
591
592requeue_echo:
593 queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
594}
595
596static bool
597allocate_buffers(struct TCP_Server_Info *server)
598{
599 if (!server->bigbuf) {
600 server->bigbuf = (char *)cifs_buf_get();
601 if (!server->bigbuf) {
602 cifs_server_dbg(VFS, "No memory for large SMB response\n");
603 msleep(3000);
604 /* retry will check if exiting */
605 return false;
606 }
607 } else if (server->large_buf) {
608 /* we are reusing a dirty large buf, clear its start */
609 memset(server->bigbuf, 0, HEADER_SIZE(server));
610 }
611
612 if (!server->smallbuf) {
613 server->smallbuf = (char *)cifs_small_buf_get();
614 if (!server->smallbuf) {
615 cifs_server_dbg(VFS, "No memory for SMB response\n");
616 msleep(1000);
617 /* retry will check if exiting */
618 return false;
619 }
620 /* beginning of smb buffer is cleared in our buf_get */
621 } else {
622 /* if existing small buf clear beginning */
623 memset(server->smallbuf, 0, HEADER_SIZE(server));
624 }
625
626 return true;
627}
628
629static bool
630server_unresponsive(struct TCP_Server_Info *server)
631{
632 /*
633 * We need to wait 3 echo intervals to make sure we handle such
634 * situations right:
635 * 1s client sends a normal SMB request
636 * 2s client gets a response
637 * 30s echo workqueue job pops, and decides we got a response recently
638 * and don't need to send another
639 * ...
640 * 65s kernel_recvmsg times out, and we see that we haven't gotten
641 * a response in >60s.
642 */
643 spin_lock(&server->srv_lock);
644 if ((server->tcpStatus == CifsGood ||
645 server->tcpStatus == CifsNeedNegotiate) &&
646 (!server->ops->can_echo || server->ops->can_echo(server)) &&
647 time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
648 spin_unlock(&server->srv_lock);
649 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
650 (3 * server->echo_interval) / HZ);
651 cifs_reconnect(server, false);
652 return true;
653 }
654 spin_unlock(&server->srv_lock);
655
656 return false;
657}
658
659static inline bool
660zero_credits(struct TCP_Server_Info *server)
661{
662 int val;
663
664 spin_lock(&server->req_lock);
665 val = server->credits + server->echo_credits + server->oplock_credits;
666 if (server->in_flight == 0 && val == 0) {
667 spin_unlock(&server->req_lock);
668 return true;
669 }
670 spin_unlock(&server->req_lock);
671 return false;
672}
673
674static int
675cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
676{
677 int length = 0;
678 int total_read;
679
680 for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
681 try_to_freeze();
682
683 /* reconnect if no credits and no requests in flight */
684 if (zero_credits(server)) {
685 cifs_reconnect(server, false);
686 return -ECONNABORTED;
687 }
688
689 if (server_unresponsive(server))
690 return -ECONNABORTED;
691 if (cifs_rdma_enabled(server) && server->smbd_conn)
692 length = smbd_recv(server->smbd_conn, smb_msg);
693 else
694 length = sock_recvmsg(server->ssocket, smb_msg, 0);
695
696 spin_lock(&server->srv_lock);
697 if (server->tcpStatus == CifsExiting) {
698 spin_unlock(&server->srv_lock);
699 return -ESHUTDOWN;
700 }
701
702 if (server->tcpStatus == CifsNeedReconnect) {
703 spin_unlock(&server->srv_lock);
704 cifs_reconnect(server, false);
705 return -ECONNABORTED;
706 }
707 spin_unlock(&server->srv_lock);
708
709 if (length == -ERESTARTSYS ||
710 length == -EAGAIN ||
711 length == -EINTR) {
712 /*
713 * Minimum sleep to prevent looping, allowing socket
714 * to clear and app threads to set tcpStatus
715 * CifsNeedReconnect if server hung.
716 */
717 usleep_range(1000, 2000);
718 length = 0;
719 continue;
720 }
721
722 if (length <= 0) {
723 cifs_dbg(FYI, "Received no data or error: %d\n", length);
724 cifs_reconnect(server, false);
725 return -ECONNABORTED;
726 }
727 }
728 return total_read;
729}
730
731int
732cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
733 unsigned int to_read)
734{
735 struct msghdr smb_msg = {};
736 struct kvec iov = {.iov_base = buf, .iov_len = to_read};
737 iov_iter_kvec(&smb_msg.msg_iter, ITER_DEST, &iov, 1, to_read);
738
739 return cifs_readv_from_socket(server, &smb_msg);
740}
741
742ssize_t
743cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
744{
745 struct msghdr smb_msg = {};
746
747 /*
748 * iov_iter_discard already sets smb_msg.type and count and iov_offset
749 * and cifs_readv_from_socket sets msg_control and msg_controllen
750 * so little to initialize in struct msghdr
751 */
752 iov_iter_discard(&smb_msg.msg_iter, ITER_DEST, to_read);
753
754 return cifs_readv_from_socket(server, &smb_msg);
755}
756
757int
758cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
759 unsigned int page_offset, unsigned int to_read)
760{
761 struct msghdr smb_msg = {};
762 struct bio_vec bv = {
763 .bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
764 iov_iter_bvec(&smb_msg.msg_iter, ITER_DEST, &bv, 1, to_read);
765 return cifs_readv_from_socket(server, &smb_msg);
766}
767
768static bool
769is_smb_response(struct TCP_Server_Info *server, unsigned char type)
770{
771 /*
772 * The first byte big endian of the length field,
773 * is actually not part of the length but the type
774 * with the most common, zero, as regular data.
775 */
776 switch (type) {
777 case RFC1002_SESSION_MESSAGE:
778 /* Regular SMB response */
779 return true;
780 case RFC1002_SESSION_KEEP_ALIVE:
781 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
782 break;
783 case RFC1002_POSITIVE_SESSION_RESPONSE:
784 cifs_dbg(FYI, "RFC 1002 positive session response\n");
785 break;
786 case RFC1002_NEGATIVE_SESSION_RESPONSE:
787 /*
788 * We get this from Windows 98 instead of an error on
789 * SMB negprot response.
790 */
791 cifs_dbg(FYI, "RFC 1002 negative session response\n");
792 /* give server a second to clean up */
793 msleep(1000);
794 /*
795 * Always try 445 first on reconnect since we get NACK
796 * on some if we ever connected to port 139 (the NACK
797 * is since we do not begin with RFC1001 session
798 * initialize frame).
799 */
800 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
801 cifs_reconnect(server, true);
802 break;
803 default:
804 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
805 cifs_reconnect(server, true);
806 }
807
808 return false;
809}
810
811void
812dequeue_mid(struct mid_q_entry *mid, bool malformed)
813{
814#ifdef CONFIG_CIFS_STATS2
815 mid->when_received = jiffies;
816#endif
817 spin_lock(&mid->server->mid_lock);
818 if (!malformed)
819 mid->mid_state = MID_RESPONSE_RECEIVED;
820 else
821 mid->mid_state = MID_RESPONSE_MALFORMED;
822 /*
823 * Trying to handle/dequeue a mid after the send_recv()
824 * function has finished processing it is a bug.
825 */
826 if (mid->mid_flags & MID_DELETED) {
827 spin_unlock(&mid->server->mid_lock);
828 pr_warn_once("trying to dequeue a deleted mid\n");
829 } else {
830 list_del_init(&mid->qhead);
831 mid->mid_flags |= MID_DELETED;
832 spin_unlock(&mid->server->mid_lock);
833 }
834}
835
836static unsigned int
837smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
838{
839 struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
840
841 /*
842 * SMB1 does not use credits.
843 */
844 if (is_smb1(server))
845 return 0;
846
847 return le16_to_cpu(shdr->CreditRequest);
848}
849
850static void
851handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
852 char *buf, int malformed)
853{
854 if (server->ops->check_trans2 &&
855 server->ops->check_trans2(mid, server, buf, malformed))
856 return;
857 mid->credits_received = smb2_get_credits_from_hdr(buf, server);
858 mid->resp_buf = buf;
859 mid->large_buf = server->large_buf;
860 /* Was previous buf put in mpx struct for multi-rsp? */
861 if (!mid->multiRsp) {
862 /* smb buffer will be freed by user thread */
863 if (server->large_buf)
864 server->bigbuf = NULL;
865 else
866 server->smallbuf = NULL;
867 }
868 dequeue_mid(mid, malformed);
869}
870
871int
872cifs_enable_signing(struct TCP_Server_Info *server, bool mnt_sign_required)
873{
874 bool srv_sign_required = server->sec_mode & server->vals->signing_required;
875 bool srv_sign_enabled = server->sec_mode & server->vals->signing_enabled;
876 bool mnt_sign_enabled;
877
878 /*
879 * Is signing required by mnt options? If not then check
880 * global_secflags to see if it is there.
881 */
882 if (!mnt_sign_required)
883 mnt_sign_required = ((global_secflags & CIFSSEC_MUST_SIGN) ==
884 CIFSSEC_MUST_SIGN);
885
886 /*
887 * If signing is required then it's automatically enabled too,
888 * otherwise, check to see if the secflags allow it.
889 */
890 mnt_sign_enabled = mnt_sign_required ? mnt_sign_required :
891 (global_secflags & CIFSSEC_MAY_SIGN);
892
893 /* If server requires signing, does client allow it? */
894 if (srv_sign_required) {
895 if (!mnt_sign_enabled) {
896 cifs_dbg(VFS, "Server requires signing, but it's disabled in SecurityFlags!\n");
897 return -EOPNOTSUPP;
898 }
899 server->sign = true;
900 }
901
902 /* If client requires signing, does server allow it? */
903 if (mnt_sign_required) {
904 if (!srv_sign_enabled) {
905 cifs_dbg(VFS, "Server does not support signing!\n");
906 return -EOPNOTSUPP;
907 }
908 server->sign = true;
909 }
910
911 if (cifs_rdma_enabled(server) && server->sign)
912 cifs_dbg(VFS, "Signing is enabled, and RDMA read/write will be disabled\n");
913
914 return 0;
915}
916
917
918static void clean_demultiplex_info(struct TCP_Server_Info *server)
919{
920 int length;
921
922 /* take it off the list, if it's not already */
923 spin_lock(&server->srv_lock);
924 list_del_init(&server->tcp_ses_list);
925 spin_unlock(&server->srv_lock);
926
927 cancel_delayed_work_sync(&server->echo);
928 cancel_delayed_work_sync(&server->resolve);
929
930 spin_lock(&server->srv_lock);
931 server->tcpStatus = CifsExiting;
932 spin_unlock(&server->srv_lock);
933 wake_up_all(&server->response_q);
934
935 /* check if we have blocked requests that need to free */
936 spin_lock(&server->req_lock);
937 if (server->credits <= 0)
938 server->credits = 1;
939 spin_unlock(&server->req_lock);
940 /*
941 * Although there should not be any requests blocked on this queue it
942 * can not hurt to be paranoid and try to wake up requests that may
943 * haven been blocked when more than 50 at time were on the wire to the
944 * same server - they now will see the session is in exit state and get
945 * out of SendReceive.
946 */
947 wake_up_all(&server->request_q);
948 /* give those requests time to exit */
949 msleep(125);
950 if (cifs_rdma_enabled(server))
951 smbd_destroy(server);
952 if (server->ssocket) {
953 sock_release(server->ssocket);
954 server->ssocket = NULL;
955 }
956
957 if (!list_empty(&server->pending_mid_q)) {
958 struct list_head dispose_list;
959 struct mid_q_entry *mid_entry;
960 struct list_head *tmp, *tmp2;
961
962 INIT_LIST_HEAD(&dispose_list);
963 spin_lock(&server->mid_lock);
964 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
965 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
966 cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
967 kref_get(&mid_entry->refcount);
968 mid_entry->mid_state = MID_SHUTDOWN;
969 list_move(&mid_entry->qhead, &dispose_list);
970 mid_entry->mid_flags |= MID_DELETED;
971 }
972 spin_unlock(&server->mid_lock);
973
974 /* now walk dispose list and issue callbacks */
975 list_for_each_safe(tmp, tmp2, &dispose_list) {
976 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
977 cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
978 list_del_init(&mid_entry->qhead);
979 mid_entry->callback(mid_entry);
980 release_mid(mid_entry);
981 }
982 /* 1/8th of sec is more than enough time for them to exit */
983 msleep(125);
984 }
985
986 if (!list_empty(&server->pending_mid_q)) {
987 /*
988 * mpx threads have not exited yet give them at least the smb
989 * send timeout time for long ops.
990 *
991 * Due to delays on oplock break requests, we need to wait at
992 * least 45 seconds before giving up on a request getting a
993 * response and going ahead and killing cifsd.
994 */
995 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
996 msleep(46000);
997 /*
998 * If threads still have not exited they are probably never
999 * coming home not much else we can do but free the memory.
1000 */
1001 }
1002
1003#ifdef CONFIG_CIFS_DFS_UPCALL
1004 kfree(server->origin_fullpath);
1005 kfree(server->leaf_fullpath);
1006#endif
1007 kfree(server);
1008
1009 length = atomic_dec_return(&tcpSesAllocCount);
1010 if (length > 0)
1011 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1012}
1013
1014static int
1015standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1016{
1017 int length;
1018 char *buf = server->smallbuf;
1019 unsigned int pdu_length = server->pdu_size;
1020
1021 /* make sure this will fit in a large buffer */
1022 if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
1023 HEADER_PREAMBLE_SIZE(server)) {
1024 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
1025 cifs_reconnect(server, true);
1026 return -ECONNABORTED;
1027 }
1028
1029 /* switch to large buffer if too big for a small one */
1030 if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
1031 server->large_buf = true;
1032 memcpy(server->bigbuf, buf, server->total_read);
1033 buf = server->bigbuf;
1034 }
1035
1036 /* now read the rest */
1037 length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
1038 pdu_length - MID_HEADER_SIZE(server));
1039
1040 if (length < 0)
1041 return length;
1042 server->total_read += length;
1043
1044 dump_smb(buf, server->total_read);
1045
1046 return cifs_handle_standard(server, mid);
1047}
1048
1049int
1050cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
1051{
1052 char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
1053 int rc;
1054
1055 /*
1056 * We know that we received enough to get to the MID as we
1057 * checked the pdu_length earlier. Now check to see
1058 * if the rest of the header is OK.
1059 *
1060 * 48 bytes is enough to display the header and a little bit
1061 * into the payload for debugging purposes.
1062 */
1063 rc = server->ops->check_message(buf, server->total_read, server);
1064 if (rc)
1065 cifs_dump_mem("Bad SMB: ", buf,
1066 min_t(unsigned int, server->total_read, 48));
1067
1068 if (server->ops->is_session_expired &&
1069 server->ops->is_session_expired(buf)) {
1070 cifs_reconnect(server, true);
1071 return -1;
1072 }
1073
1074 if (server->ops->is_status_pending &&
1075 server->ops->is_status_pending(buf, server))
1076 return -1;
1077
1078 if (!mid)
1079 return rc;
1080
1081 handle_mid(mid, server, buf, rc);
1082 return 0;
1083}
1084
1085static void
1086smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
1087{
1088 struct smb2_hdr *shdr = (struct smb2_hdr *)buffer;
1089 int scredits, in_flight;
1090
1091 /*
1092 * SMB1 does not use credits.
1093 */
1094 if (is_smb1(server))
1095 return;
1096
1097 if (shdr->CreditRequest) {
1098 spin_lock(&server->req_lock);
1099 server->credits += le16_to_cpu(shdr->CreditRequest);
1100 scredits = server->credits;
1101 in_flight = server->in_flight;
1102 spin_unlock(&server->req_lock);
1103 wake_up(&server->request_q);
1104
1105 trace_smb3_hdr_credits(server->CurrentMid,
1106 server->conn_id, server->hostname, scredits,
1107 le16_to_cpu(shdr->CreditRequest), in_flight);
1108 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
1109 __func__, le16_to_cpu(shdr->CreditRequest),
1110 scredits);
1111 }
1112}
1113
1114
1115static int
1116cifs_demultiplex_thread(void *p)
1117{
1118 int i, num_mids, length;
1119 struct TCP_Server_Info *server = p;
1120 unsigned int pdu_length;
1121 unsigned int next_offset;
1122 char *buf = NULL;
1123 struct task_struct *task_to_wake = NULL;
1124 struct mid_q_entry *mids[MAX_COMPOUND];
1125 char *bufs[MAX_COMPOUND];
1126 unsigned int noreclaim_flag, num_io_timeout = 0;
1127
1128 noreclaim_flag = memalloc_noreclaim_save();
1129 cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
1130
1131 length = atomic_inc_return(&tcpSesAllocCount);
1132 if (length > 1)
1133 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
1134
1135 set_freezable();
1136 allow_kernel_signal(SIGKILL);
1137 while (server->tcpStatus != CifsExiting) {
1138 if (try_to_freeze())
1139 continue;
1140
1141 if (!allocate_buffers(server))
1142 continue;
1143
1144 server->large_buf = false;
1145 buf = server->smallbuf;
1146 pdu_length = 4; /* enough to get RFC1001 header */
1147
1148 length = cifs_read_from_socket(server, buf, pdu_length);
1149 if (length < 0)
1150 continue;
1151
1152 if (is_smb1(server))
1153 server->total_read = length;
1154 else
1155 server->total_read = 0;
1156
1157 /*
1158 * The right amount was read from socket - 4 bytes,
1159 * so we can now interpret the length field.
1160 */
1161 pdu_length = get_rfc1002_length(buf);
1162
1163 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
1164 if (!is_smb_response(server, buf[0]))
1165 continue;
1166next_pdu:
1167 server->pdu_size = pdu_length;
1168
1169 /* make sure we have enough to get to the MID */
1170 if (server->pdu_size < MID_HEADER_SIZE(server)) {
1171 cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
1172 server->pdu_size);
1173 cifs_reconnect(server, true);
1174 continue;
1175 }
1176
1177 /* read down to the MID */
1178 length = cifs_read_from_socket(server,
1179 buf + HEADER_PREAMBLE_SIZE(server),
1180 MID_HEADER_SIZE(server));
1181 if (length < 0)
1182 continue;
1183 server->total_read += length;
1184
1185 if (server->ops->next_header) {
1186 next_offset = server->ops->next_header(buf);
1187 if (next_offset)
1188 server->pdu_size = next_offset;
1189 }
1190
1191 memset(mids, 0, sizeof(mids));
1192 memset(bufs, 0, sizeof(bufs));
1193 num_mids = 0;
1194
1195 if (server->ops->is_transform_hdr &&
1196 server->ops->receive_transform &&
1197 server->ops->is_transform_hdr(buf)) {
1198 length = server->ops->receive_transform(server,
1199 mids,
1200 bufs,
1201 &num_mids);
1202 } else {
1203 mids[0] = server->ops->find_mid(server, buf);
1204 bufs[0] = buf;
1205 num_mids = 1;
1206
1207 if (!mids[0] || !mids[0]->receive)
1208 length = standard_receive3(server, mids[0]);
1209 else
1210 length = mids[0]->receive(server, mids[0]);
1211 }
1212
1213 if (length < 0) {
1214 for (i = 0; i < num_mids; i++)
1215 if (mids[i])
1216 release_mid(mids[i]);
1217 continue;
1218 }
1219
1220 if (server->ops->is_status_io_timeout &&
1221 server->ops->is_status_io_timeout(buf)) {
1222 num_io_timeout++;
1223 if (num_io_timeout > NUM_STATUS_IO_TIMEOUT) {
1224 cifs_reconnect(server, false);
1225 num_io_timeout = 0;
1226 continue;
1227 }
1228 }
1229
1230 server->lstrp = jiffies;
1231
1232 for (i = 0; i < num_mids; i++) {
1233 if (mids[i] != NULL) {
1234 mids[i]->resp_buf_size = server->pdu_size;
1235
1236 if (bufs[i] && server->ops->is_network_name_deleted)
1237 server->ops->is_network_name_deleted(bufs[i],
1238 server);
1239
1240 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1241 mids[i]->callback(mids[i]);
1242
1243 release_mid(mids[i]);
1244 } else if (server->ops->is_oplock_break &&
1245 server->ops->is_oplock_break(bufs[i],
1246 server)) {
1247 smb2_add_credits_from_hdr(bufs[i], server);
1248 cifs_dbg(FYI, "Received oplock break\n");
1249 } else {
1250 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1251 atomic_read(&mid_count));
1252 cifs_dump_mem("Received Data is: ", bufs[i],
1253 HEADER_SIZE(server));
1254 smb2_add_credits_from_hdr(bufs[i], server);
1255#ifdef CONFIG_CIFS_DEBUG2
1256 if (server->ops->dump_detail)
1257 server->ops->dump_detail(bufs[i],
1258 server);
1259 cifs_dump_mids(server);
1260#endif /* CIFS_DEBUG2 */
1261 }
1262 }
1263
1264 if (pdu_length > server->pdu_size) {
1265 if (!allocate_buffers(server))
1266 continue;
1267 pdu_length -= server->pdu_size;
1268 server->total_read = 0;
1269 server->large_buf = false;
1270 buf = server->smallbuf;
1271 goto next_pdu;
1272 }
1273 } /* end while !EXITING */
1274
1275 /* buffer usually freed in free_mid - need to free it here on exit */
1276 cifs_buf_release(server->bigbuf);
1277 if (server->smallbuf) /* no sense logging a debug message if NULL */
1278 cifs_small_buf_release(server->smallbuf);
1279
1280 task_to_wake = xchg(&server->tsk, NULL);
1281 clean_demultiplex_info(server);
1282
1283 /* if server->tsk was NULL then wait for a signal before exiting */
1284 if (!task_to_wake) {
1285 set_current_state(TASK_INTERRUPTIBLE);
1286 while (!signal_pending(current)) {
1287 schedule();
1288 set_current_state(TASK_INTERRUPTIBLE);
1289 }
1290 set_current_state(TASK_RUNNING);
1291 }
1292
1293 memalloc_noreclaim_restore(noreclaim_flag);
1294 module_put_and_kthread_exit(0);
1295}
1296
1297/*
1298 * Returns true if srcaddr isn't specified and rhs isn't specified, or
1299 * if srcaddr is specified and matches the IP address of the rhs argument
1300 */
1301bool
1302cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1303{
1304 switch (srcaddr->sa_family) {
1305 case AF_UNSPEC:
1306 return (rhs->sa_family == AF_UNSPEC);
1307 case AF_INET: {
1308 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1309 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1310 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1311 }
1312 case AF_INET6: {
1313 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1314 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1315 return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
1316 }
1317 default:
1318 WARN_ON(1);
1319 return false; /* don't expect to be here */
1320 }
1321}
1322
1323/*
1324 * If no port is specified in addr structure, we try to match with 445 port
1325 * and if it fails - with 139 ports. It should be called only if address
1326 * families of server and addr are equal.
1327 */
1328static bool
1329match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1330{
1331 __be16 port, *sport;
1332
1333 /* SMBDirect manages its own ports, don't match it here */
1334 if (server->rdma)
1335 return true;
1336
1337 switch (addr->sa_family) {
1338 case AF_INET:
1339 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1340 port = ((struct sockaddr_in *) addr)->sin_port;
1341 break;
1342 case AF_INET6:
1343 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1344 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1345 break;
1346 default:
1347 WARN_ON(1);
1348 return false;
1349 }
1350
1351 if (!port) {
1352 port = htons(CIFS_PORT);
1353 if (port == *sport)
1354 return true;
1355
1356 port = htons(RFC1001_PORT);
1357 }
1358
1359 return port == *sport;
1360}
1361
1362static bool match_server_address(struct TCP_Server_Info *server, struct sockaddr *addr)
1363{
1364 switch (addr->sa_family) {
1365 case AF_INET: {
1366 struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
1367 struct sockaddr_in *srv_addr4 =
1368 (struct sockaddr_in *)&server->dstaddr;
1369
1370 if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
1371 return false;
1372 break;
1373 }
1374 case AF_INET6: {
1375 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
1376 struct sockaddr_in6 *srv_addr6 =
1377 (struct sockaddr_in6 *)&server->dstaddr;
1378
1379 if (!ipv6_addr_equal(&addr6->sin6_addr,
1380 &srv_addr6->sin6_addr))
1381 return false;
1382 if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
1383 return false;
1384 break;
1385 }
1386 default:
1387 WARN_ON(1);
1388 return false; /* don't expect to be here */
1389 }
1390
1391 return true;
1392}
1393
1394static bool
1395match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1396{
1397 /*
1398 * The select_sectype function should either return the ctx->sectype
1399 * that was specified, or "Unspecified" if that sectype was not
1400 * compatible with the given NEGOTIATE request.
1401 */
1402 if (server->ops->select_sectype(server, ctx->sectype)
1403 == Unspecified)
1404 return false;
1405
1406 /*
1407 * Now check if signing mode is acceptable. No need to check
1408 * global_secflags at this point since if MUST_SIGN is set then
1409 * the server->sign had better be too.
1410 */
1411 if (ctx->sign && !server->sign)
1412 return false;
1413
1414 return true;
1415}
1416
1417static bool dfs_src_pathname_equal(const char *s1, const char *s2)
1418{
1419 if (strlen(s1) != strlen(s2))
1420 return false;
1421 for (; *s1; s1++, s2++) {
1422 if (*s1 == '/' || *s1 == '\\') {
1423 if (*s2 != '/' && *s2 != '\\')
1424 return false;
1425 } else if (tolower(*s1) != tolower(*s2))
1426 return false;
1427 }
1428 return true;
1429}
1430
1431/* this function must be called with srv_lock held */
1432static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx,
1433 bool dfs_super_cmp)
1434{
1435 struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1436
1437 if (ctx->nosharesock)
1438 return 0;
1439
1440 /* this server does not share socket */
1441 if (server->nosharesock)
1442 return 0;
1443
1444 /* If multidialect negotiation see if existing sessions match one */
1445 if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1446 if (server->vals->protocol_id < SMB30_PROT_ID)
1447 return 0;
1448 } else if (strcmp(ctx->vals->version_string,
1449 SMBDEFAULT_VERSION_STRING) == 0) {
1450 if (server->vals->protocol_id < SMB21_PROT_ID)
1451 return 0;
1452 } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1453 return 0;
1454
1455 if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1456 return 0;
1457
1458 if (!cifs_match_ipaddr((struct sockaddr *)&ctx->srcaddr,
1459 (struct sockaddr *)&server->srcaddr))
1460 return 0;
1461 /*
1462 * When matching DFS superblocks, we only check for original source pathname as the
1463 * currently connected target might be different than the one parsed earlier in i.e.
1464 * mount.cifs(8).
1465 */
1466 if (dfs_super_cmp) {
1467 if (!ctx->source || !server->origin_fullpath ||
1468 !dfs_src_pathname_equal(server->origin_fullpath, ctx->source))
1469 return 0;
1470 } else {
1471 /* Skip addr, hostname and port matching for DFS connections */
1472 if (server->leaf_fullpath) {
1473 if (!ctx->leaf_fullpath ||
1474 strcasecmp(server->leaf_fullpath, ctx->leaf_fullpath))
1475 return 0;
1476 } else if (strcasecmp(server->hostname, ctx->server_hostname) ||
1477 !match_server_address(server, addr) ||
1478 !match_port(server, addr)) {
1479 return 0;
1480 }
1481 }
1482
1483 if (!match_security(server, ctx))
1484 return 0;
1485
1486 if (server->echo_interval != ctx->echo_interval * HZ)
1487 return 0;
1488
1489 if (server->rdma != ctx->rdma)
1490 return 0;
1491
1492 if (server->ignore_signature != ctx->ignore_signature)
1493 return 0;
1494
1495 if (server->min_offload != ctx->min_offload)
1496 return 0;
1497
1498 return 1;
1499}
1500
1501struct TCP_Server_Info *
1502cifs_find_tcp_session(struct smb3_fs_context *ctx)
1503{
1504 struct TCP_Server_Info *server;
1505
1506 spin_lock(&cifs_tcp_ses_lock);
1507 list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1508 spin_lock(&server->srv_lock);
1509 /*
1510 * Skip ses channels since they're only handled in lower layers
1511 * (e.g. cifs_send_recv).
1512 */
1513 if (CIFS_SERVER_IS_CHAN(server) || !match_server(server, ctx, false)) {
1514 spin_unlock(&server->srv_lock);
1515 continue;
1516 }
1517 spin_unlock(&server->srv_lock);
1518
1519 ++server->srv_count;
1520 spin_unlock(&cifs_tcp_ses_lock);
1521 cifs_dbg(FYI, "Existing tcp session with server found\n");
1522 return server;
1523 }
1524 spin_unlock(&cifs_tcp_ses_lock);
1525 return NULL;
1526}
1527
1528void
1529cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1530{
1531 struct task_struct *task;
1532
1533 spin_lock(&cifs_tcp_ses_lock);
1534 if (--server->srv_count > 0) {
1535 spin_unlock(&cifs_tcp_ses_lock);
1536 return;
1537 }
1538
1539 /* srv_count can never go negative */
1540 WARN_ON(server->srv_count < 0);
1541
1542 put_net(cifs_net_ns(server));
1543
1544 list_del_init(&server->tcp_ses_list);
1545 spin_unlock(&cifs_tcp_ses_lock);
1546
1547 /* For secondary channels, we pick up ref-count on the primary server */
1548 if (CIFS_SERVER_IS_CHAN(server))
1549 cifs_put_tcp_session(server->primary_server, from_reconnect);
1550
1551 cancel_delayed_work_sync(&server->echo);
1552 cancel_delayed_work_sync(&server->resolve);
1553
1554 if (from_reconnect)
1555 /*
1556 * Avoid deadlock here: reconnect work calls
1557 * cifs_put_tcp_session() at its end. Need to be sure
1558 * that reconnect work does nothing with server pointer after
1559 * that step.
1560 */
1561 cancel_delayed_work(&server->reconnect);
1562 else
1563 cancel_delayed_work_sync(&server->reconnect);
1564
1565 spin_lock(&server->srv_lock);
1566 server->tcpStatus = CifsExiting;
1567 spin_unlock(&server->srv_lock);
1568
1569 cifs_crypto_secmech_release(server);
1570
1571 kfree_sensitive(server->session_key.response);
1572 server->session_key.response = NULL;
1573 server->session_key.len = 0;
1574 kfree(server->hostname);
1575 server->hostname = NULL;
1576
1577 task = xchg(&server->tsk, NULL);
1578 if (task)
1579 send_sig(SIGKILL, task, 1);
1580}
1581
1582struct TCP_Server_Info *
1583cifs_get_tcp_session(struct smb3_fs_context *ctx,
1584 struct TCP_Server_Info *primary_server)
1585{
1586 struct TCP_Server_Info *tcp_ses = NULL;
1587 int rc;
1588
1589 cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1590
1591 /* see if we already have a matching tcp_ses */
1592 tcp_ses = cifs_find_tcp_session(ctx);
1593 if (tcp_ses)
1594 return tcp_ses;
1595
1596 tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1597 if (!tcp_ses) {
1598 rc = -ENOMEM;
1599 goto out_err;
1600 }
1601
1602 tcp_ses->hostname = kstrdup(ctx->server_hostname, GFP_KERNEL);
1603 if (!tcp_ses->hostname) {
1604 rc = -ENOMEM;
1605 goto out_err;
1606 }
1607
1608 if (ctx->leaf_fullpath) {
1609 tcp_ses->leaf_fullpath = kstrdup(ctx->leaf_fullpath, GFP_KERNEL);
1610 if (!tcp_ses->leaf_fullpath) {
1611 rc = -ENOMEM;
1612 goto out_err;
1613 }
1614 tcp_ses->current_fullpath = tcp_ses->leaf_fullpath;
1615 }
1616
1617 if (ctx->nosharesock)
1618 tcp_ses->nosharesock = true;
1619
1620 tcp_ses->ops = ctx->ops;
1621 tcp_ses->vals = ctx->vals;
1622 cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1623
1624 tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1625 tcp_ses->noblockcnt = ctx->rootfs;
1626 tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1627 tcp_ses->noautotune = ctx->noautotune;
1628 tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1629 tcp_ses->rdma = ctx->rdma;
1630 tcp_ses->in_flight = 0;
1631 tcp_ses->max_in_flight = 0;
1632 tcp_ses->credits = 1;
1633 if (primary_server) {
1634 spin_lock(&cifs_tcp_ses_lock);
1635 ++primary_server->srv_count;
1636 spin_unlock(&cifs_tcp_ses_lock);
1637 tcp_ses->primary_server = primary_server;
1638 }
1639 init_waitqueue_head(&tcp_ses->response_q);
1640 init_waitqueue_head(&tcp_ses->request_q);
1641 INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1642 mutex_init(&tcp_ses->_srv_mutex);
1643 memcpy(tcp_ses->workstation_RFC1001_name,
1644 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1645 memcpy(tcp_ses->server_RFC1001_name,
1646 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1647 tcp_ses->session_estab = false;
1648 tcp_ses->sequence_number = 0;
1649 tcp_ses->reconnect_instance = 1;
1650 tcp_ses->lstrp = jiffies;
1651 tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1652 spin_lock_init(&tcp_ses->req_lock);
1653 spin_lock_init(&tcp_ses->srv_lock);
1654 spin_lock_init(&tcp_ses->mid_lock);
1655 INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1656 INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1657 INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1658 INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
1659 INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1660 mutex_init(&tcp_ses->reconnect_mutex);
1661#ifdef CONFIG_CIFS_DFS_UPCALL
1662 mutex_init(&tcp_ses->refpath_lock);
1663#endif
1664 memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1665 sizeof(tcp_ses->srcaddr));
1666 memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1667 sizeof(tcp_ses->dstaddr));
1668 if (ctx->use_client_guid)
1669 memcpy(tcp_ses->client_guid, ctx->client_guid,
1670 SMB2_CLIENT_GUID_SIZE);
1671 else
1672 generate_random_uuid(tcp_ses->client_guid);
1673 /*
1674 * at this point we are the only ones with the pointer
1675 * to the struct since the kernel thread not created yet
1676 * no need to spinlock this init of tcpStatus or srv_count
1677 */
1678 tcp_ses->tcpStatus = CifsNew;
1679 ++tcp_ses->srv_count;
1680
1681 if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1682 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1683 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1684 else
1685 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1686 if (tcp_ses->rdma) {
1687#ifndef CONFIG_CIFS_SMB_DIRECT
1688 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1689 rc = -ENOENT;
1690 goto out_err_crypto_release;
1691#endif
1692 tcp_ses->smbd_conn = smbd_get_connection(
1693 tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1694 if (tcp_ses->smbd_conn) {
1695 cifs_dbg(VFS, "RDMA transport established\n");
1696 rc = 0;
1697 goto smbd_connected;
1698 } else {
1699 rc = -ENOENT;
1700 goto out_err_crypto_release;
1701 }
1702 }
1703 rc = ip_connect(tcp_ses);
1704 if (rc < 0) {
1705 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1706 goto out_err_crypto_release;
1707 }
1708smbd_connected:
1709 /*
1710 * since we're in a cifs function already, we know that
1711 * this will succeed. No need for try_module_get().
1712 */
1713 __module_get(THIS_MODULE);
1714 tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1715 tcp_ses, "cifsd");
1716 if (IS_ERR(tcp_ses->tsk)) {
1717 rc = PTR_ERR(tcp_ses->tsk);
1718 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1719 module_put(THIS_MODULE);
1720 goto out_err_crypto_release;
1721 }
1722 tcp_ses->min_offload = ctx->min_offload;
1723 /*
1724 * at this point we are the only ones with the pointer
1725 * to the struct since the kernel thread not created yet
1726 * no need to spinlock this update of tcpStatus
1727 */
1728 spin_lock(&tcp_ses->srv_lock);
1729 tcp_ses->tcpStatus = CifsNeedNegotiate;
1730 spin_unlock(&tcp_ses->srv_lock);
1731
1732 if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1733 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1734 else
1735 tcp_ses->max_credits = ctx->max_credits;
1736
1737 tcp_ses->nr_targets = 1;
1738 tcp_ses->ignore_signature = ctx->ignore_signature;
1739 /* thread spawned, put it on the list */
1740 spin_lock(&cifs_tcp_ses_lock);
1741 list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1742 spin_unlock(&cifs_tcp_ses_lock);
1743
1744 /* queue echo request delayed work */
1745 queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1746
1747 /* queue dns resolution delayed work */
1748 cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
1749 __func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);
1750
1751 queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));
1752
1753 return tcp_ses;
1754
1755out_err_crypto_release:
1756 cifs_crypto_secmech_release(tcp_ses);
1757
1758 put_net(cifs_net_ns(tcp_ses));
1759
1760out_err:
1761 if (tcp_ses) {
1762 if (CIFS_SERVER_IS_CHAN(tcp_ses))
1763 cifs_put_tcp_session(tcp_ses->primary_server, false);
1764 kfree(tcp_ses->hostname);
1765 kfree(tcp_ses->leaf_fullpath);
1766 if (tcp_ses->ssocket)
1767 sock_release(tcp_ses->ssocket);
1768 kfree(tcp_ses);
1769 }
1770 return ERR_PTR(rc);
1771}
1772
1773/* this function must be called with ses_lock held */
1774static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1775{
1776 if (ctx->sectype != Unspecified &&
1777 ctx->sectype != ses->sectype)
1778 return 0;
1779
1780 /*
1781 * If an existing session is limited to less channels than
1782 * requested, it should not be reused
1783 */
1784 spin_lock(&ses->chan_lock);
1785 if (ses->chan_max < ctx->max_channels) {
1786 spin_unlock(&ses->chan_lock);
1787 return 0;
1788 }
1789 spin_unlock(&ses->chan_lock);
1790
1791 switch (ses->sectype) {
1792 case Kerberos:
1793 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1794 return 0;
1795 break;
1796 default:
1797 /* NULL username means anonymous session */
1798 if (ses->user_name == NULL) {
1799 if (!ctx->nullauth)
1800 return 0;
1801 break;
1802 }
1803
1804 /* anything else takes username/password */
1805 if (strncmp(ses->user_name,
1806 ctx->username ? ctx->username : "",
1807 CIFS_MAX_USERNAME_LEN))
1808 return 0;
1809 if ((ctx->username && strlen(ctx->username) != 0) &&
1810 ses->password != NULL &&
1811 strncmp(ses->password,
1812 ctx->password ? ctx->password : "",
1813 CIFS_MAX_PASSWORD_LEN))
1814 return 0;
1815 }
1816 return 1;
1817}
1818
1819/**
1820 * cifs_setup_ipc - helper to setup the IPC tcon for the session
1821 * @ses: smb session to issue the request on
1822 * @ctx: the superblock configuration context to use for building the
1823 * new tree connection for the IPC (interprocess communication RPC)
1824 *
1825 * A new IPC connection is made and stored in the session
1826 * tcon_ipc. The IPC tcon has the same lifetime as the session.
1827 */
1828static int
1829cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1830{
1831 int rc = 0, xid;
1832 struct cifs_tcon *tcon;
1833 char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1834 bool seal = false;
1835 struct TCP_Server_Info *server = ses->server;
1836
1837 /*
1838 * If the mount request that resulted in the creation of the
1839 * session requires encryption, force IPC to be encrypted too.
1840 */
1841 if (ctx->seal) {
1842 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1843 seal = true;
1844 else {
1845 cifs_server_dbg(VFS,
1846 "IPC: server doesn't support encryption\n");
1847 return -EOPNOTSUPP;
1848 }
1849 }
1850
1851 tcon = tconInfoAlloc();
1852 if (tcon == NULL)
1853 return -ENOMEM;
1854
1855 scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1856
1857 xid = get_xid();
1858 tcon->ses = ses;
1859 tcon->ipc = true;
1860 tcon->seal = seal;
1861 rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1862 free_xid(xid);
1863
1864 if (rc) {
1865 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1866 tconInfoFree(tcon);
1867 goto out;
1868 }
1869
1870 cifs_dbg(FYI, "IPC tcon rc=%d ipc tid=0x%x\n", rc, tcon->tid);
1871
1872 spin_lock(&tcon->tc_lock);
1873 tcon->status = TID_GOOD;
1874 spin_unlock(&tcon->tc_lock);
1875 ses->tcon_ipc = tcon;
1876out:
1877 return rc;
1878}
1879
1880/**
1881 * cifs_free_ipc - helper to release the session IPC tcon
1882 * @ses: smb session to unmount the IPC from
1883 *
1884 * Needs to be called everytime a session is destroyed.
1885 *
1886 * On session close, the IPC is closed and the server must release all tcons of the session.
1887 * No need to send a tree disconnect here.
1888 *
1889 * Besides, it will make the server to not close durable and resilient files on session close, as
1890 * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1891 */
1892static int
1893cifs_free_ipc(struct cifs_ses *ses)
1894{
1895 struct cifs_tcon *tcon = ses->tcon_ipc;
1896
1897 if (tcon == NULL)
1898 return 0;
1899
1900 tconInfoFree(tcon);
1901 ses->tcon_ipc = NULL;
1902 return 0;
1903}
1904
1905static struct cifs_ses *
1906cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1907{
1908 struct cifs_ses *ses;
1909
1910 spin_lock(&cifs_tcp_ses_lock);
1911 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1912 spin_lock(&ses->ses_lock);
1913 if (ses->ses_status == SES_EXITING) {
1914 spin_unlock(&ses->ses_lock);
1915 continue;
1916 }
1917 if (!match_session(ses, ctx)) {
1918 spin_unlock(&ses->ses_lock);
1919 continue;
1920 }
1921 spin_unlock(&ses->ses_lock);
1922
1923 ++ses->ses_count;
1924 spin_unlock(&cifs_tcp_ses_lock);
1925 return ses;
1926 }
1927 spin_unlock(&cifs_tcp_ses_lock);
1928 return NULL;
1929}
1930
1931void cifs_put_smb_ses(struct cifs_ses *ses)
1932{
1933 unsigned int rc, xid;
1934 unsigned int chan_count;
1935 struct TCP_Server_Info *server = ses->server;
1936
1937 spin_lock(&ses->ses_lock);
1938 if (ses->ses_status == SES_EXITING) {
1939 spin_unlock(&ses->ses_lock);
1940 return;
1941 }
1942 spin_unlock(&ses->ses_lock);
1943
1944 cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
1945 cifs_dbg(FYI,
1946 "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->tree_name : "NONE");
1947
1948 spin_lock(&cifs_tcp_ses_lock);
1949 if (--ses->ses_count > 0) {
1950 spin_unlock(&cifs_tcp_ses_lock);
1951 return;
1952 }
1953 spin_unlock(&cifs_tcp_ses_lock);
1954
1955 /* ses_count can never go negative */
1956 WARN_ON(ses->ses_count < 0);
1957
1958 if (ses->ses_status == SES_GOOD)
1959 ses->ses_status = SES_EXITING;
1960
1961 cifs_free_ipc(ses);
1962
1963 if (ses->ses_status == SES_EXITING && server->ops->logoff) {
1964 xid = get_xid();
1965 rc = server->ops->logoff(xid, ses);
1966 if (rc)
1967 cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
1968 __func__, rc);
1969 _free_xid(xid);
1970 }
1971
1972 spin_lock(&cifs_tcp_ses_lock);
1973 list_del_init(&ses->smb_ses_list);
1974 spin_unlock(&cifs_tcp_ses_lock);
1975
1976 chan_count = ses->chan_count;
1977
1978 /* close any extra channels */
1979 if (chan_count > 1) {
1980 int i;
1981
1982 for (i = 1; i < chan_count; i++) {
1983 if (ses->chans[i].iface) {
1984 kref_put(&ses->chans[i].iface->refcount, release_iface);
1985 ses->chans[i].iface = NULL;
1986 }
1987 cifs_put_tcp_session(ses->chans[i].server, 0);
1988 ses->chans[i].server = NULL;
1989 }
1990 }
1991
1992 sesInfoFree(ses);
1993 cifs_put_tcp_session(server, 0);
1994}
1995
1996#ifdef CONFIG_KEYS
1997
1998/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
1999#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
2000
2001/* Populate username and pw fields from keyring if possible */
2002static int
2003cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
2004{
2005 int rc = 0;
2006 int is_domain = 0;
2007 const char *delim, *payload;
2008 char *desc;
2009 ssize_t len;
2010 struct key *key;
2011 struct TCP_Server_Info *server = ses->server;
2012 struct sockaddr_in *sa;
2013 struct sockaddr_in6 *sa6;
2014 const struct user_key_payload *upayload;
2015
2016 desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
2017 if (!desc)
2018 return -ENOMEM;
2019
2020 /* try to find an address key first */
2021 switch (server->dstaddr.ss_family) {
2022 case AF_INET:
2023 sa = (struct sockaddr_in *)&server->dstaddr;
2024 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
2025 break;
2026 case AF_INET6:
2027 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
2028 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
2029 break;
2030 default:
2031 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
2032 server->dstaddr.ss_family);
2033 rc = -EINVAL;
2034 goto out_err;
2035 }
2036
2037 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2038 key = request_key(&key_type_logon, desc, "");
2039 if (IS_ERR(key)) {
2040 if (!ses->domainName) {
2041 cifs_dbg(FYI, "domainName is NULL\n");
2042 rc = PTR_ERR(key);
2043 goto out_err;
2044 }
2045
2046 /* didn't work, try to find a domain key */
2047 sprintf(desc, "cifs:d:%s", ses->domainName);
2048 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
2049 key = request_key(&key_type_logon, desc, "");
2050 if (IS_ERR(key)) {
2051 rc = PTR_ERR(key);
2052 goto out_err;
2053 }
2054 is_domain = 1;
2055 }
2056
2057 down_read(&key->sem);
2058 upayload = user_key_payload_locked(key);
2059 if (IS_ERR_OR_NULL(upayload)) {
2060 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
2061 goto out_key_put;
2062 }
2063
2064 /* find first : in payload */
2065 payload = upayload->data;
2066 delim = strnchr(payload, upayload->datalen, ':');
2067 cifs_dbg(FYI, "payload=%s\n", payload);
2068 if (!delim) {
2069 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
2070 upayload->datalen);
2071 rc = -EINVAL;
2072 goto out_key_put;
2073 }
2074
2075 len = delim - payload;
2076 if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
2077 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
2078 len);
2079 rc = -EINVAL;
2080 goto out_key_put;
2081 }
2082
2083 ctx->username = kstrndup(payload, len, GFP_KERNEL);
2084 if (!ctx->username) {
2085 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
2086 len);
2087 rc = -ENOMEM;
2088 goto out_key_put;
2089 }
2090 cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
2091
2092 len = key->datalen - (len + 1);
2093 if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
2094 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
2095 rc = -EINVAL;
2096 kfree(ctx->username);
2097 ctx->username = NULL;
2098 goto out_key_put;
2099 }
2100
2101 ++delim;
2102 ctx->password = kstrndup(delim, len, GFP_KERNEL);
2103 if (!ctx->password) {
2104 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
2105 len);
2106 rc = -ENOMEM;
2107 kfree(ctx->username);
2108 ctx->username = NULL;
2109 goto out_key_put;
2110 }
2111
2112 /*
2113 * If we have a domain key then we must set the domainName in the
2114 * for the request.
2115 */
2116 if (is_domain && ses->domainName) {
2117 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
2118 if (!ctx->domainname) {
2119 cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
2120 len);
2121 rc = -ENOMEM;
2122 kfree(ctx->username);
2123 ctx->username = NULL;
2124 kfree_sensitive(ctx->password);
2125 ctx->password = NULL;
2126 goto out_key_put;
2127 }
2128 }
2129
2130 strscpy(ctx->workstation_name, ses->workstation_name, sizeof(ctx->workstation_name));
2131
2132out_key_put:
2133 up_read(&key->sem);
2134 key_put(key);
2135out_err:
2136 kfree(desc);
2137 cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
2138 return rc;
2139}
2140#else /* ! CONFIG_KEYS */
2141static inline int
2142cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
2143 struct cifs_ses *ses __attribute__((unused)))
2144{
2145 return -ENOSYS;
2146}
2147#endif /* CONFIG_KEYS */
2148
2149/**
2150 * cifs_get_smb_ses - get a session matching @ctx data from @server
2151 * @server: server to setup the session to
2152 * @ctx: superblock configuration context to use to setup the session
2153 *
2154 * This function assumes it is being called from cifs_mount() where we
2155 * already got a server reference (server refcount +1). See
2156 * cifs_get_tcon() for refcount explanations.
2157 */
2158struct cifs_ses *
2159cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
2160{
2161 int rc = 0;
2162 unsigned int xid;
2163 struct cifs_ses *ses;
2164 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2165 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2166
2167 xid = get_xid();
2168
2169 ses = cifs_find_smb_ses(server, ctx);
2170 if (ses) {
2171 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
2172 ses->ses_status);
2173
2174 spin_lock(&ses->chan_lock);
2175 if (cifs_chan_needs_reconnect(ses, server)) {
2176 spin_unlock(&ses->chan_lock);
2177 cifs_dbg(FYI, "Session needs reconnect\n");
2178
2179 mutex_lock(&ses->session_mutex);
2180 rc = cifs_negotiate_protocol(xid, ses, server);
2181 if (rc) {
2182 mutex_unlock(&ses->session_mutex);
2183 /* problem -- put our ses reference */
2184 cifs_put_smb_ses(ses);
2185 free_xid(xid);
2186 return ERR_PTR(rc);
2187 }
2188
2189 rc = cifs_setup_session(xid, ses, server,
2190 ctx->local_nls);
2191 if (rc) {
2192 mutex_unlock(&ses->session_mutex);
2193 /* problem -- put our reference */
2194 cifs_put_smb_ses(ses);
2195 free_xid(xid);
2196 return ERR_PTR(rc);
2197 }
2198 mutex_unlock(&ses->session_mutex);
2199
2200 spin_lock(&ses->chan_lock);
2201 }
2202 spin_unlock(&ses->chan_lock);
2203
2204 /* existing SMB ses has a server reference already */
2205 cifs_put_tcp_session(server, 0);
2206 free_xid(xid);
2207 return ses;
2208 }
2209
2210 rc = -ENOMEM;
2211
2212 cifs_dbg(FYI, "Existing smb sess not found\n");
2213 ses = sesInfoAlloc();
2214 if (ses == NULL)
2215 goto get_ses_fail;
2216
2217 /* new SMB session uses our server ref */
2218 ses->server = server;
2219 if (server->dstaddr.ss_family == AF_INET6)
2220 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
2221 else
2222 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
2223
2224 if (ctx->username) {
2225 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
2226 if (!ses->user_name)
2227 goto get_ses_fail;
2228 }
2229
2230 /* ctx->password freed at unmount */
2231 if (ctx->password) {
2232 ses->password = kstrdup(ctx->password, GFP_KERNEL);
2233 if (!ses->password)
2234 goto get_ses_fail;
2235 }
2236 if (ctx->domainname) {
2237 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
2238 if (!ses->domainName)
2239 goto get_ses_fail;
2240 }
2241
2242 strscpy(ses->workstation_name, ctx->workstation_name, sizeof(ses->workstation_name));
2243
2244 if (ctx->domainauto)
2245 ses->domainAuto = ctx->domainauto;
2246 ses->cred_uid = ctx->cred_uid;
2247 ses->linux_uid = ctx->linux_uid;
2248
2249 ses->sectype = ctx->sectype;
2250 ses->sign = ctx->sign;
2251
2252 /* add server as first channel */
2253 spin_lock(&ses->chan_lock);
2254 ses->chans[0].server = server;
2255 ses->chan_count = 1;
2256 ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
2257 ses->chans_need_reconnect = 1;
2258 spin_unlock(&ses->chan_lock);
2259
2260 mutex_lock(&ses->session_mutex);
2261 rc = cifs_negotiate_protocol(xid, ses, server);
2262 if (!rc)
2263 rc = cifs_setup_session(xid, ses, server, ctx->local_nls);
2264 mutex_unlock(&ses->session_mutex);
2265
2266 /* each channel uses a different signing key */
2267 spin_lock(&ses->chan_lock);
2268 memcpy(ses->chans[0].signkey, ses->smb3signingkey,
2269 sizeof(ses->smb3signingkey));
2270 spin_unlock(&ses->chan_lock);
2271
2272 if (rc)
2273 goto get_ses_fail;
2274
2275 /*
2276 * success, put it on the list and add it as first channel
2277 * note: the session becomes active soon after this. So you'll
2278 * need to lock before changing something in the session.
2279 */
2280 spin_lock(&cifs_tcp_ses_lock);
2281 list_add(&ses->smb_ses_list, &server->smb_ses_list);
2282 spin_unlock(&cifs_tcp_ses_lock);
2283
2284 cifs_setup_ipc(ses, ctx);
2285
2286 free_xid(xid);
2287
2288 return ses;
2289
2290get_ses_fail:
2291 sesInfoFree(ses);
2292 free_xid(xid);
2293 return ERR_PTR(rc);
2294}
2295
2296/* this function must be called with tc_lock held */
2297static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx, bool dfs_super_cmp)
2298{
2299 if (tcon->status == TID_EXITING)
2300 return 0;
2301 /* Skip UNC validation when matching DFS superblocks */
2302 if (!dfs_super_cmp && strncmp(tcon->tree_name, ctx->UNC, MAX_TREE_SIZE))
2303 return 0;
2304 if (tcon->seal != ctx->seal)
2305 return 0;
2306 if (tcon->snapshot_time != ctx->snapshot_time)
2307 return 0;
2308 if (tcon->handle_timeout != ctx->handle_timeout)
2309 return 0;
2310 if (tcon->no_lease != ctx->no_lease)
2311 return 0;
2312 if (tcon->nodelete != ctx->nodelete)
2313 return 0;
2314 return 1;
2315}
2316
2317static struct cifs_tcon *
2318cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2319{
2320 struct cifs_tcon *tcon;
2321
2322 spin_lock(&cifs_tcp_ses_lock);
2323 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
2324 spin_lock(&tcon->tc_lock);
2325 if (!match_tcon(tcon, ctx, false)) {
2326 spin_unlock(&tcon->tc_lock);
2327 continue;
2328 }
2329 ++tcon->tc_count;
2330 spin_unlock(&tcon->tc_lock);
2331 spin_unlock(&cifs_tcp_ses_lock);
2332 return tcon;
2333 }
2334 spin_unlock(&cifs_tcp_ses_lock);
2335 return NULL;
2336}
2337
2338void
2339cifs_put_tcon(struct cifs_tcon *tcon)
2340{
2341 unsigned int xid;
2342 struct cifs_ses *ses;
2343
2344 /*
2345 * IPC tcon share the lifetime of their session and are
2346 * destroyed in the session put function
2347 */
2348 if (tcon == NULL || tcon->ipc)
2349 return;
2350
2351 ses = tcon->ses;
2352 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2353 spin_lock(&cifs_tcp_ses_lock);
2354 spin_lock(&tcon->tc_lock);
2355 if (--tcon->tc_count > 0) {
2356 spin_unlock(&tcon->tc_lock);
2357 spin_unlock(&cifs_tcp_ses_lock);
2358 return;
2359 }
2360
2361 /* tc_count can never go negative */
2362 WARN_ON(tcon->tc_count < 0);
2363
2364 list_del_init(&tcon->tcon_list);
2365 spin_unlock(&tcon->tc_lock);
2366 spin_unlock(&cifs_tcp_ses_lock);
2367
2368 /* cancel polling of interfaces */
2369 cancel_delayed_work_sync(&tcon->query_interfaces);
2370
2371 if (tcon->use_witness) {
2372 int rc;
2373
2374 rc = cifs_swn_unregister(tcon);
2375 if (rc < 0) {
2376 cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2377 __func__, rc);
2378 }
2379 }
2380
2381 xid = get_xid();
2382 if (ses->server->ops->tree_disconnect)
2383 ses->server->ops->tree_disconnect(xid, tcon);
2384 _free_xid(xid);
2385
2386 cifs_fscache_release_super_cookie(tcon);
2387 tconInfoFree(tcon);
2388 cifs_put_smb_ses(ses);
2389}
2390
2391/**
2392 * cifs_get_tcon - get a tcon matching @ctx data from @ses
2393 * @ses: smb session to issue the request on
2394 * @ctx: the superblock configuration context to use for building the
2395 *
2396 * - tcon refcount is the number of mount points using the tcon.
2397 * - ses refcount is the number of tcon using the session.
2398 *
2399 * 1. This function assumes it is being called from cifs_mount() where
2400 * we already got a session reference (ses refcount +1).
2401 *
2402 * 2. Since we're in the context of adding a mount point, the end
2403 * result should be either:
2404 *
2405 * a) a new tcon already allocated with refcount=1 (1 mount point) and
2406 * its session refcount incremented (1 new tcon). This +1 was
2407 * already done in (1).
2408 *
2409 * b) an existing tcon with refcount+1 (add a mount point to it) and
2410 * identical ses refcount (no new tcon). Because of (1) we need to
2411 * decrement the ses refcount.
2412 */
2413static struct cifs_tcon *
2414cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2415{
2416 int rc, xid;
2417 struct cifs_tcon *tcon;
2418
2419 tcon = cifs_find_tcon(ses, ctx);
2420 if (tcon) {
2421 /*
2422 * tcon has refcount already incremented but we need to
2423 * decrement extra ses reference gotten by caller (case b)
2424 */
2425 cifs_dbg(FYI, "Found match on UNC path\n");
2426 cifs_put_smb_ses(ses);
2427 return tcon;
2428 }
2429
2430 if (!ses->server->ops->tree_connect) {
2431 rc = -ENOSYS;
2432 goto out_fail;
2433 }
2434
2435 tcon = tconInfoAlloc();
2436 if (tcon == NULL) {
2437 rc = -ENOMEM;
2438 goto out_fail;
2439 }
2440
2441 if (ctx->snapshot_time) {
2442 if (ses->server->vals->protocol_id == 0) {
2443 cifs_dbg(VFS,
2444 "Use SMB2 or later for snapshot mount option\n");
2445 rc = -EOPNOTSUPP;
2446 goto out_fail;
2447 } else
2448 tcon->snapshot_time = ctx->snapshot_time;
2449 }
2450
2451 if (ctx->handle_timeout) {
2452 if (ses->server->vals->protocol_id == 0) {
2453 cifs_dbg(VFS,
2454 "Use SMB2.1 or later for handle timeout option\n");
2455 rc = -EOPNOTSUPP;
2456 goto out_fail;
2457 } else
2458 tcon->handle_timeout = ctx->handle_timeout;
2459 }
2460
2461 tcon->ses = ses;
2462 if (ctx->password) {
2463 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2464 if (!tcon->password) {
2465 rc = -ENOMEM;
2466 goto out_fail;
2467 }
2468 }
2469
2470 if (ctx->seal) {
2471 if (ses->server->vals->protocol_id == 0) {
2472 cifs_dbg(VFS,
2473 "SMB3 or later required for encryption\n");
2474 rc = -EOPNOTSUPP;
2475 goto out_fail;
2476 } else if (tcon->ses->server->capabilities &
2477 SMB2_GLOBAL_CAP_ENCRYPTION)
2478 tcon->seal = true;
2479 else {
2480 cifs_dbg(VFS, "Encryption is not supported on share\n");
2481 rc = -EOPNOTSUPP;
2482 goto out_fail;
2483 }
2484 }
2485
2486 if (ctx->linux_ext) {
2487 if (ses->server->posix_ext_supported) {
2488 tcon->posix_extensions = true;
2489 pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2490 } else if ((ses->server->vals->protocol_id == SMB311_PROT_ID) ||
2491 (strcmp(ses->server->vals->version_string,
2492 SMB3ANY_VERSION_STRING) == 0) ||
2493 (strcmp(ses->server->vals->version_string,
2494 SMBDEFAULT_VERSION_STRING) == 0)) {
2495 cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2496 rc = -EOPNOTSUPP;
2497 goto out_fail;
2498 } else {
2499 cifs_dbg(VFS, "Check vers= mount option. SMB3.11 "
2500 "disabled but required for POSIX extensions\n");
2501 rc = -EOPNOTSUPP;
2502 goto out_fail;
2503 }
2504 }
2505
2506 xid = get_xid();
2507 rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2508 ctx->local_nls);
2509 free_xid(xid);
2510 cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2511 if (rc)
2512 goto out_fail;
2513
2514 tcon->use_persistent = false;
2515 /* check if SMB2 or later, CIFS does not support persistent handles */
2516 if (ctx->persistent) {
2517 if (ses->server->vals->protocol_id == 0) {
2518 cifs_dbg(VFS,
2519 "SMB3 or later required for persistent handles\n");
2520 rc = -EOPNOTSUPP;
2521 goto out_fail;
2522 } else if (ses->server->capabilities &
2523 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2524 tcon->use_persistent = true;
2525 else /* persistent handles requested but not supported */ {
2526 cifs_dbg(VFS,
2527 "Persistent handles not supported on share\n");
2528 rc = -EOPNOTSUPP;
2529 goto out_fail;
2530 }
2531 } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2532 && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2533 && (ctx->nopersistent == false)) {
2534 cifs_dbg(FYI, "enabling persistent handles\n");
2535 tcon->use_persistent = true;
2536 } else if (ctx->resilient) {
2537 if (ses->server->vals->protocol_id == 0) {
2538 cifs_dbg(VFS,
2539 "SMB2.1 or later required for resilient handles\n");
2540 rc = -EOPNOTSUPP;
2541 goto out_fail;
2542 }
2543 tcon->use_resilient = true;
2544 }
2545
2546 tcon->use_witness = false;
2547 if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2548 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2549 if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2550 /*
2551 * Set witness in use flag in first place
2552 * to retry registration in the echo task
2553 */
2554 tcon->use_witness = true;
2555 /* And try to register immediately */
2556 rc = cifs_swn_register(tcon);
2557 if (rc < 0) {
2558 cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2559 goto out_fail;
2560 }
2561 } else {
2562 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2563 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2564 rc = -EOPNOTSUPP;
2565 goto out_fail;
2566 }
2567 } else {
2568 cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2569 rc = -EOPNOTSUPP;
2570 goto out_fail;
2571 }
2572 }
2573
2574 /* If the user really knows what they are doing they can override */
2575 if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2576 if (ctx->cache_ro)
2577 cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2578 else if (ctx->cache_rw)
2579 cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2580 }
2581
2582 if (ctx->no_lease) {
2583 if (ses->server->vals->protocol_id == 0) {
2584 cifs_dbg(VFS,
2585 "SMB2 or later required for nolease option\n");
2586 rc = -EOPNOTSUPP;
2587 goto out_fail;
2588 } else
2589 tcon->no_lease = ctx->no_lease;
2590 }
2591
2592 /*
2593 * We can have only one retry value for a connection to a share so for
2594 * resources mounted more than once to the same server share the last
2595 * value passed in for the retry flag is used.
2596 */
2597 tcon->retry = ctx->retry;
2598 tcon->nocase = ctx->nocase;
2599 tcon->broken_sparse_sup = ctx->no_sparse;
2600 if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
2601 tcon->nohandlecache = ctx->nohandlecache;
2602 else
2603 tcon->nohandlecache = true;
2604 tcon->nodelete = ctx->nodelete;
2605 tcon->local_lease = ctx->local_lease;
2606 INIT_LIST_HEAD(&tcon->pending_opens);
2607 tcon->status = TID_GOOD;
2608
2609 INIT_DELAYED_WORK(&tcon->query_interfaces,
2610 smb2_query_server_interfaces);
2611 if (ses->server->dialect >= SMB30_PROT_ID &&
2612 (ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
2613 /* schedule query interfaces poll */
2614 queue_delayed_work(cifsiod_wq, &tcon->query_interfaces,
2615 (SMB_INTERFACE_POLL_INTERVAL * HZ));
2616 }
2617
2618 spin_lock(&cifs_tcp_ses_lock);
2619 list_add(&tcon->tcon_list, &ses->tcon_list);
2620 spin_unlock(&cifs_tcp_ses_lock);
2621
2622 return tcon;
2623
2624out_fail:
2625 tconInfoFree(tcon);
2626 return ERR_PTR(rc);
2627}
2628
2629void
2630cifs_put_tlink(struct tcon_link *tlink)
2631{
2632 if (!tlink || IS_ERR(tlink))
2633 return;
2634
2635 if (!atomic_dec_and_test(&tlink->tl_count) ||
2636 test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2637 tlink->tl_time = jiffies;
2638 return;
2639 }
2640
2641 if (!IS_ERR(tlink_tcon(tlink)))
2642 cifs_put_tcon(tlink_tcon(tlink));
2643 kfree(tlink);
2644 return;
2645}
2646
2647static int
2648compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2649{
2650 struct cifs_sb_info *old = CIFS_SB(sb);
2651 struct cifs_sb_info *new = mnt_data->cifs_sb;
2652 unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2653 unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2654
2655 if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2656 return 0;
2657
2658 if (old->mnt_cifs_serverino_autodisabled)
2659 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2660
2661 if (oldflags != newflags)
2662 return 0;
2663
2664 /*
2665 * We want to share sb only if we don't specify an r/wsize or
2666 * specified r/wsize is greater than or equal to existing one.
2667 */
2668 if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2669 return 0;
2670
2671 if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2672 return 0;
2673
2674 if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2675 !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2676 return 0;
2677
2678 if (old->ctx->file_mode != new->ctx->file_mode ||
2679 old->ctx->dir_mode != new->ctx->dir_mode)
2680 return 0;
2681
2682 if (strcmp(old->local_nls->charset, new->local_nls->charset))
2683 return 0;
2684
2685 if (old->ctx->acregmax != new->ctx->acregmax)
2686 return 0;
2687 if (old->ctx->acdirmax != new->ctx->acdirmax)
2688 return 0;
2689 if (old->ctx->closetimeo != new->ctx->closetimeo)
2690 return 0;
2691
2692 return 1;
2693}
2694
2695static int
2696match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2697{
2698 struct cifs_sb_info *old = CIFS_SB(sb);
2699 struct cifs_sb_info *new = mnt_data->cifs_sb;
2700 bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2701 old->prepath;
2702 bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2703 new->prepath;
2704
2705 if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2706 return 1;
2707 else if (!old_set && !new_set)
2708 return 1;
2709
2710 return 0;
2711}
2712
2713int
2714cifs_match_super(struct super_block *sb, void *data)
2715{
2716 struct cifs_mnt_data *mnt_data = data;
2717 struct smb3_fs_context *ctx;
2718 struct cifs_sb_info *cifs_sb;
2719 struct TCP_Server_Info *tcp_srv;
2720 struct cifs_ses *ses;
2721 struct cifs_tcon *tcon;
2722 struct tcon_link *tlink;
2723 bool dfs_super_cmp;
2724 int rc = 0;
2725
2726 spin_lock(&cifs_tcp_ses_lock);
2727 cifs_sb = CIFS_SB(sb);
2728 tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2729 if (tlink == NULL) {
2730 /* can not match superblock if tlink were ever null */
2731 spin_unlock(&cifs_tcp_ses_lock);
2732 return 0;
2733 }
2734 tcon = tlink_tcon(tlink);
2735 ses = tcon->ses;
2736 tcp_srv = ses->server;
2737
2738 dfs_super_cmp = IS_ENABLED(CONFIG_CIFS_DFS_UPCALL) && tcp_srv->origin_fullpath;
2739
2740 ctx = mnt_data->ctx;
2741
2742 spin_lock(&tcp_srv->srv_lock);
2743 spin_lock(&ses->ses_lock);
2744 spin_lock(&tcon->tc_lock);
2745 if (!match_server(tcp_srv, ctx, dfs_super_cmp) ||
2746 !match_session(ses, ctx) ||
2747 !match_tcon(tcon, ctx, dfs_super_cmp) ||
2748 !match_prepath(sb, mnt_data)) {
2749 rc = 0;
2750 goto out;
2751 }
2752
2753 rc = compare_mount_options(sb, mnt_data);
2754out:
2755 spin_unlock(&tcon->tc_lock);
2756 spin_unlock(&ses->ses_lock);
2757 spin_unlock(&tcp_srv->srv_lock);
2758
2759 spin_unlock(&cifs_tcp_ses_lock);
2760 cifs_put_tlink(tlink);
2761 return rc;
2762}
2763
2764#ifdef CONFIG_DEBUG_LOCK_ALLOC
2765static struct lock_class_key cifs_key[2];
2766static struct lock_class_key cifs_slock_key[2];
2767
2768static inline void
2769cifs_reclassify_socket4(struct socket *sock)
2770{
2771 struct sock *sk = sock->sk;
2772 BUG_ON(!sock_allow_reclassification(sk));
2773 sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2774 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2775}
2776
2777static inline void
2778cifs_reclassify_socket6(struct socket *sock)
2779{
2780 struct sock *sk = sock->sk;
2781 BUG_ON(!sock_allow_reclassification(sk));
2782 sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2783 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2784}
2785#else
2786static inline void
2787cifs_reclassify_socket4(struct socket *sock)
2788{
2789}
2790
2791static inline void
2792cifs_reclassify_socket6(struct socket *sock)
2793{
2794}
2795#endif
2796
2797/* See RFC1001 section 14 on representation of Netbios names */
2798static void rfc1002mangle(char *target, char *source, unsigned int length)
2799{
2800 unsigned int i, j;
2801
2802 for (i = 0, j = 0; i < (length); i++) {
2803 /* mask a nibble at a time and encode */
2804 target[j] = 'A' + (0x0F & (source[i] >> 4));
2805 target[j+1] = 'A' + (0x0F & source[i]);
2806 j += 2;
2807 }
2808
2809}
2810
2811static int
2812bind_socket(struct TCP_Server_Info *server)
2813{
2814 int rc = 0;
2815 if (server->srcaddr.ss_family != AF_UNSPEC) {
2816 /* Bind to the specified local IP address */
2817 struct socket *socket = server->ssocket;
2818 rc = socket->ops->bind(socket,
2819 (struct sockaddr *) &server->srcaddr,
2820 sizeof(server->srcaddr));
2821 if (rc < 0) {
2822 struct sockaddr_in *saddr4;
2823 struct sockaddr_in6 *saddr6;
2824 saddr4 = (struct sockaddr_in *)&server->srcaddr;
2825 saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2826 if (saddr6->sin6_family == AF_INET6)
2827 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2828 &saddr6->sin6_addr, rc);
2829 else
2830 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2831 &saddr4->sin_addr.s_addr, rc);
2832 }
2833 }
2834 return rc;
2835}
2836
2837static int
2838ip_rfc1001_connect(struct TCP_Server_Info *server)
2839{
2840 int rc = 0;
2841 /*
2842 * some servers require RFC1001 sessinit before sending
2843 * negprot - BB check reconnection in case where second
2844 * sessinit is sent but no second negprot
2845 */
2846 struct rfc1002_session_packet *ses_init_buf;
2847 unsigned int req_noscope_len;
2848 struct smb_hdr *smb_buf;
2849
2850 ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
2851 GFP_KERNEL);
2852
2853 if (ses_init_buf) {
2854 ses_init_buf->trailer.session_req.called_len = 32;
2855
2856 if (server->server_RFC1001_name[0] != 0)
2857 rfc1002mangle(ses_init_buf->trailer.
2858 session_req.called_name,
2859 server->server_RFC1001_name,
2860 RFC1001_NAME_LEN_WITH_NULL);
2861 else
2862 rfc1002mangle(ses_init_buf->trailer.
2863 session_req.called_name,
2864 DEFAULT_CIFS_CALLED_NAME,
2865 RFC1001_NAME_LEN_WITH_NULL);
2866
2867 ses_init_buf->trailer.session_req.calling_len = 32;
2868
2869 /*
2870 * calling name ends in null (byte 16) from old smb
2871 * convention.
2872 */
2873 if (server->workstation_RFC1001_name[0] != 0)
2874 rfc1002mangle(ses_init_buf->trailer.
2875 session_req.calling_name,
2876 server->workstation_RFC1001_name,
2877 RFC1001_NAME_LEN_WITH_NULL);
2878 else
2879 rfc1002mangle(ses_init_buf->trailer.
2880 session_req.calling_name,
2881 "LINUX_CIFS_CLNT",
2882 RFC1001_NAME_LEN_WITH_NULL);
2883
2884 ses_init_buf->trailer.session_req.scope1 = 0;
2885 ses_init_buf->trailer.session_req.scope2 = 0;
2886 smb_buf = (struct smb_hdr *)ses_init_buf;
2887
2888 /* sizeof RFC1002_SESSION_REQUEST with no scopes */
2889 req_noscope_len = sizeof(struct rfc1002_session_packet) - 2;
2890
2891 /* == cpu_to_be32(0x81000044) */
2892 smb_buf->smb_buf_length =
2893 cpu_to_be32((RFC1002_SESSION_REQUEST << 24) | req_noscope_len);
2894 rc = smb_send(server, smb_buf, 0x44);
2895 kfree(ses_init_buf);
2896 /*
2897 * RFC1001 layer in at least one server
2898 * requires very short break before negprot
2899 * presumably because not expecting negprot
2900 * to follow so fast. This is a simple
2901 * solution that works without
2902 * complicating the code and causes no
2903 * significant slowing down on mount
2904 * for everyone else
2905 */
2906 usleep_range(1000, 2000);
2907 }
2908 /*
2909 * else the negprot may still work without this
2910 * even though malloc failed
2911 */
2912
2913 return rc;
2914}
2915
2916static int
2917generic_ip_connect(struct TCP_Server_Info *server)
2918{
2919 int rc = 0;
2920 __be16 sport;
2921 int slen, sfamily;
2922 struct socket *socket = server->ssocket;
2923 struct sockaddr *saddr;
2924
2925 saddr = (struct sockaddr *) &server->dstaddr;
2926
2927 if (server->dstaddr.ss_family == AF_INET6) {
2928 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
2929
2930 sport = ipv6->sin6_port;
2931 slen = sizeof(struct sockaddr_in6);
2932 sfamily = AF_INET6;
2933 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
2934 ntohs(sport));
2935 } else {
2936 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
2937
2938 sport = ipv4->sin_port;
2939 slen = sizeof(struct sockaddr_in);
2940 sfamily = AF_INET;
2941 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
2942 ntohs(sport));
2943 }
2944
2945 if (socket == NULL) {
2946 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
2947 IPPROTO_TCP, &socket, 1);
2948 if (rc < 0) {
2949 cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
2950 server->ssocket = NULL;
2951 return rc;
2952 }
2953
2954 /* BB other socket options to set KEEPALIVE, NODELAY? */
2955 cifs_dbg(FYI, "Socket created\n");
2956 server->ssocket = socket;
2957 socket->sk->sk_allocation = GFP_NOFS;
2958 socket->sk->sk_use_task_frag = false;
2959 if (sfamily == AF_INET6)
2960 cifs_reclassify_socket6(socket);
2961 else
2962 cifs_reclassify_socket4(socket);
2963 }
2964
2965 rc = bind_socket(server);
2966 if (rc < 0)
2967 return rc;
2968
2969 /*
2970 * Eventually check for other socket options to change from
2971 * the default. sock_setsockopt not used because it expects
2972 * user space buffer
2973 */
2974 socket->sk->sk_rcvtimeo = 7 * HZ;
2975 socket->sk->sk_sndtimeo = 5 * HZ;
2976
2977 /* make the bufsizes depend on wsize/rsize and max requests */
2978 if (server->noautotune) {
2979 if (socket->sk->sk_sndbuf < (200 * 1024))
2980 socket->sk->sk_sndbuf = 200 * 1024;
2981 if (socket->sk->sk_rcvbuf < (140 * 1024))
2982 socket->sk->sk_rcvbuf = 140 * 1024;
2983 }
2984
2985 if (server->tcp_nodelay)
2986 tcp_sock_set_nodelay(socket->sk);
2987
2988 cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
2989 socket->sk->sk_sndbuf,
2990 socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
2991
2992 rc = socket->ops->connect(socket, saddr, slen,
2993 server->noblockcnt ? O_NONBLOCK : 0);
2994 /*
2995 * When mounting SMB root file systems, we do not want to block in
2996 * connect. Otherwise bail out and then let cifs_reconnect() perform
2997 * reconnect failover - if possible.
2998 */
2999 if (server->noblockcnt && rc == -EINPROGRESS)
3000 rc = 0;
3001 if (rc < 0) {
3002 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
3003 trace_smb3_connect_err(server->hostname, server->conn_id, &server->dstaddr, rc);
3004 sock_release(socket);
3005 server->ssocket = NULL;
3006 return rc;
3007 }
3008 trace_smb3_connect_done(server->hostname, server->conn_id, &server->dstaddr);
3009 if (sport == htons(RFC1001_PORT))
3010 rc = ip_rfc1001_connect(server);
3011
3012 return rc;
3013}
3014
3015static int
3016ip_connect(struct TCP_Server_Info *server)
3017{
3018 __be16 *sport;
3019 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3020 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3021
3022 if (server->dstaddr.ss_family == AF_INET6)
3023 sport = &addr6->sin6_port;
3024 else
3025 sport = &addr->sin_port;
3026
3027 if (*sport == 0) {
3028 int rc;
3029
3030 /* try with 445 port at first */
3031 *sport = htons(CIFS_PORT);
3032
3033 rc = generic_ip_connect(server);
3034 if (rc >= 0)
3035 return rc;
3036
3037 /* if it failed, try with 139 port */
3038 *sport = htons(RFC1001_PORT);
3039 }
3040
3041 return generic_ip_connect(server);
3042}
3043
3044#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3045void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
3046 struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3047{
3048 /*
3049 * If we are reconnecting then should we check to see if
3050 * any requested capabilities changed locally e.g. via
3051 * remount but we can not do much about it here
3052 * if they have (even if we could detect it by the following)
3053 * Perhaps we could add a backpointer to array of sb from tcon
3054 * or if we change to make all sb to same share the same
3055 * sb as NFS - then we only have one backpointer to sb.
3056 * What if we wanted to mount the server share twice once with
3057 * and once without posixacls or posix paths?
3058 */
3059 __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3060
3061 if (ctx && ctx->no_linux_ext) {
3062 tcon->fsUnixInfo.Capability = 0;
3063 tcon->unix_ext = 0; /* Unix Extensions disabled */
3064 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
3065 return;
3066 } else if (ctx)
3067 tcon->unix_ext = 1; /* Unix Extensions supported */
3068
3069 if (!tcon->unix_ext) {
3070 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
3071 return;
3072 }
3073
3074 if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
3075 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
3076 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
3077 /*
3078 * check for reconnect case in which we do not
3079 * want to change the mount behavior if we can avoid it
3080 */
3081 if (ctx == NULL) {
3082 /*
3083 * turn off POSIX ACL and PATHNAMES if not set
3084 * originally at mount time
3085 */
3086 if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
3087 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3088 if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3089 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3090 cifs_dbg(VFS, "POSIXPATH support change\n");
3091 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3092 } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
3093 cifs_dbg(VFS, "possible reconnect error\n");
3094 cifs_dbg(VFS, "server disabled POSIX path support\n");
3095 }
3096 }
3097
3098 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3099 cifs_dbg(VFS, "per-share encryption not supported yet\n");
3100
3101 cap &= CIFS_UNIX_CAP_MASK;
3102 if (ctx && ctx->no_psx_acl)
3103 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
3104 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
3105 cifs_dbg(FYI, "negotiated posix acl support\n");
3106 if (cifs_sb)
3107 cifs_sb->mnt_cifs_flags |=
3108 CIFS_MOUNT_POSIXACL;
3109 }
3110
3111 if (ctx && ctx->posix_paths == 0)
3112 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
3113 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
3114 cifs_dbg(FYI, "negotiate posix pathnames\n");
3115 if (cifs_sb)
3116 cifs_sb->mnt_cifs_flags |=
3117 CIFS_MOUNT_POSIX_PATHS;
3118 }
3119
3120 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
3121#ifdef CONFIG_CIFS_DEBUG2
3122 if (cap & CIFS_UNIX_FCNTL_CAP)
3123 cifs_dbg(FYI, "FCNTL cap\n");
3124 if (cap & CIFS_UNIX_EXTATTR_CAP)
3125 cifs_dbg(FYI, "EXTATTR cap\n");
3126 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
3127 cifs_dbg(FYI, "POSIX path cap\n");
3128 if (cap & CIFS_UNIX_XATTR_CAP)
3129 cifs_dbg(FYI, "XATTR cap\n");
3130 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
3131 cifs_dbg(FYI, "POSIX ACL cap\n");
3132 if (cap & CIFS_UNIX_LARGE_READ_CAP)
3133 cifs_dbg(FYI, "very large read cap\n");
3134 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
3135 cifs_dbg(FYI, "very large write cap\n");
3136 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
3137 cifs_dbg(FYI, "transport encryption cap\n");
3138 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
3139 cifs_dbg(FYI, "mandatory transport encryption cap\n");
3140#endif /* CIFS_DEBUG2 */
3141 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
3142 if (ctx == NULL)
3143 cifs_dbg(FYI, "resetting capabilities failed\n");
3144 else
3145 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");
3146
3147 }
3148 }
3149}
3150#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3151
3152int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
3153{
3154 struct smb3_fs_context *ctx = cifs_sb->ctx;
3155
3156 INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
3157
3158 spin_lock_init(&cifs_sb->tlink_tree_lock);
3159 cifs_sb->tlink_tree = RB_ROOT;
3160
3161 cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n",
3162 ctx->file_mode, ctx->dir_mode);
3163
3164 /* this is needed for ASCII cp to Unicode converts */
3165 if (ctx->iocharset == NULL) {
3166 /* load_nls_default cannot return null */
3167 cifs_sb->local_nls = load_nls_default();
3168 } else {
3169 cifs_sb->local_nls = load_nls(ctx->iocharset);
3170 if (cifs_sb->local_nls == NULL) {
3171 cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
3172 ctx->iocharset);
3173 return -ELIBACC;
3174 }
3175 }
3176 ctx->local_nls = cifs_sb->local_nls;
3177
3178 smb3_update_mnt_flags(cifs_sb);
3179
3180 if (ctx->direct_io)
3181 cifs_dbg(FYI, "mounting share using direct i/o\n");
3182 if (ctx->cache_ro) {
3183 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
3184 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
3185 } else if (ctx->cache_rw) {
3186 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
3187 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
3188 CIFS_MOUNT_RW_CACHE);
3189 }
3190
3191 if ((ctx->cifs_acl) && (ctx->dynperm))
3192 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
3193
3194 if (ctx->prepath) {
3195 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
3196 if (cifs_sb->prepath == NULL)
3197 return -ENOMEM;
3198 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3199 }
3200
3201 return 0;
3202}
3203
3204/* Release all succeed connections */
3205void cifs_mount_put_conns(struct cifs_mount_ctx *mnt_ctx)
3206{
3207 int rc = 0;
3208
3209 if (mnt_ctx->tcon)
3210 cifs_put_tcon(mnt_ctx->tcon);
3211 else if (mnt_ctx->ses)
3212 cifs_put_smb_ses(mnt_ctx->ses);
3213 else if (mnt_ctx->server)
3214 cifs_put_tcp_session(mnt_ctx->server, 0);
3215 mnt_ctx->cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
3216 free_xid(mnt_ctx->xid);
3217}
3218
3219int cifs_mount_get_session(struct cifs_mount_ctx *mnt_ctx)
3220{
3221 struct TCP_Server_Info *server = NULL;
3222 struct smb3_fs_context *ctx;
3223 struct cifs_ses *ses = NULL;
3224 unsigned int xid;
3225 int rc = 0;
3226
3227 xid = get_xid();
3228
3229 if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->fs_ctx)) {
3230 rc = -EINVAL;
3231 goto out;
3232 }
3233 ctx = mnt_ctx->fs_ctx;
3234
3235 /* get a reference to a tcp session */
3236 server = cifs_get_tcp_session(ctx, NULL);
3237 if (IS_ERR(server)) {
3238 rc = PTR_ERR(server);
3239 server = NULL;
3240 goto out;
3241 }
3242
3243 /* get a reference to a SMB session */
3244 ses = cifs_get_smb_ses(server, ctx);
3245 if (IS_ERR(ses)) {
3246 rc = PTR_ERR(ses);
3247 ses = NULL;
3248 goto out;
3249 }
3250
3251 if ((ctx->persistent == true) && (!(ses->server->capabilities &
3252 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
3253 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
3254 rc = -EOPNOTSUPP;
3255 }
3256
3257out:
3258 mnt_ctx->xid = xid;
3259 mnt_ctx->server = server;
3260 mnt_ctx->ses = ses;
3261 mnt_ctx->tcon = NULL;
3262
3263 return rc;
3264}
3265
3266int cifs_mount_get_tcon(struct cifs_mount_ctx *mnt_ctx)
3267{
3268 struct TCP_Server_Info *server;
3269 struct cifs_sb_info *cifs_sb;
3270 struct smb3_fs_context *ctx;
3271 struct cifs_tcon *tcon = NULL;
3272 int rc = 0;
3273
3274 if (WARN_ON_ONCE(!mnt_ctx || !mnt_ctx->server || !mnt_ctx->ses || !mnt_ctx->fs_ctx ||
3275 !mnt_ctx->cifs_sb)) {
3276 rc = -EINVAL;
3277 goto out;
3278 }
3279 server = mnt_ctx->server;
3280 ctx = mnt_ctx->fs_ctx;
3281 cifs_sb = mnt_ctx->cifs_sb;
3282
3283 /* search for existing tcon to this server share */
3284 tcon = cifs_get_tcon(mnt_ctx->ses, ctx);
3285 if (IS_ERR(tcon)) {
3286 rc = PTR_ERR(tcon);
3287 tcon = NULL;
3288 goto out;
3289 }
3290
3291 /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
3292 if (tcon->posix_extensions)
3293 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
3294
3295#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3296 /* tell server which Unix caps we support */
3297 if (cap_unix(tcon->ses)) {
3298 /*
3299 * reset of caps checks mount to see if unix extensions disabled
3300 * for just this mount.
3301 */
3302 reset_cifs_unix_caps(mnt_ctx->xid, tcon, cifs_sb, ctx);
3303 spin_lock(&tcon->ses->server->srv_lock);
3304 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
3305 (le64_to_cpu(tcon->fsUnixInfo.Capability) &
3306 CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
3307 spin_unlock(&tcon->ses->server->srv_lock);
3308 rc = -EACCES;
3309 goto out;
3310 }
3311 spin_unlock(&tcon->ses->server->srv_lock);
3312 } else
3313#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3314 tcon->unix_ext = 0; /* server does not support them */
3315
3316 /* do not care if a following call succeed - informational */
3317 if (!tcon->pipe && server->ops->qfs_tcon) {
3318 server->ops->qfs_tcon(mnt_ctx->xid, tcon, cifs_sb);
3319 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
3320 if (tcon->fsDevInfo.DeviceCharacteristics &
3321 cpu_to_le32(FILE_READ_ONLY_DEVICE))
3322 cifs_dbg(VFS, "mounted to read only share\n");
3323 else if ((cifs_sb->mnt_cifs_flags &
3324 CIFS_MOUNT_RW_CACHE) == 0)
3325 cifs_dbg(VFS, "read only mount of RW share\n");
3326 /* no need to log a RW mount of a typical RW share */
3327 }
3328 }
3329
3330 /*
3331 * Clamp the rsize/wsize mount arguments if they are too big for the server
3332 * and set the rsize/wsize to the negotiated values if not passed in by
3333 * the user on mount
3334 */
3335 if ((cifs_sb->ctx->wsize == 0) ||
3336 (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
3337 cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
3338 if ((cifs_sb->ctx->rsize == 0) ||
3339 (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
3340 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
3341
3342 /*
3343 * The cookie is initialized from volume info returned above.
3344 * Inside cifs_fscache_get_super_cookie it checks
3345 * that we do not get super cookie twice.
3346 */
3347 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE)
3348 cifs_fscache_get_super_cookie(tcon);
3349
3350out:
3351 mnt_ctx->tcon = tcon;
3352 return rc;
3353}
3354
3355static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
3356 struct cifs_tcon *tcon)
3357{
3358 struct tcon_link *tlink;
3359
3360 /* hang the tcon off of the superblock */
3361 tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
3362 if (tlink == NULL)
3363 return -ENOMEM;
3364
3365 tlink->tl_uid = ses->linux_uid;
3366 tlink->tl_tcon = tcon;
3367 tlink->tl_time = jiffies;
3368 set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
3369 set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3370
3371 cifs_sb->master_tlink = tlink;
3372 spin_lock(&cifs_sb->tlink_tree_lock);
3373 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
3374 spin_unlock(&cifs_sb->tlink_tree_lock);
3375
3376 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
3377 TLINK_IDLE_EXPIRE);
3378 return 0;
3379}
3380
3381static int
3382cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3383 unsigned int xid,
3384 struct cifs_tcon *tcon,
3385 struct cifs_sb_info *cifs_sb,
3386 char *full_path,
3387 int added_treename)
3388{
3389 int rc;
3390 char *s;
3391 char sep, tmp;
3392 int skip = added_treename ? 1 : 0;
3393
3394 sep = CIFS_DIR_SEP(cifs_sb);
3395 s = full_path;
3396
3397 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3398 while (rc == 0) {
3399 /* skip separators */
3400 while (*s == sep)
3401 s++;
3402 if (!*s)
3403 break;
3404 /* next separator */
3405 while (*s && *s != sep)
3406 s++;
3407 /*
3408 * if the treename is added, we then have to skip the first
3409 * part within the separators
3410 */
3411 if (skip) {
3412 skip = 0;
3413 continue;
3414 }
3415 /*
3416 * temporarily null-terminate the path at the end of
3417 * the current component
3418 */
3419 tmp = *s;
3420 *s = 0;
3421 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3422 full_path);
3423 *s = tmp;
3424 }
3425 return rc;
3426}
3427
3428/*
3429 * Check if path is remote (i.e. a DFS share).
3430 *
3431 * Return -EREMOTE if it is, otherwise 0 or -errno.
3432 */
3433int cifs_is_path_remote(struct cifs_mount_ctx *mnt_ctx)
3434{
3435 int rc;
3436 struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
3437 struct TCP_Server_Info *server = mnt_ctx->server;
3438 unsigned int xid = mnt_ctx->xid;
3439 struct cifs_tcon *tcon = mnt_ctx->tcon;
3440 struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
3441 char *full_path;
3442
3443 if (!server->ops->is_path_accessible)
3444 return -EOPNOTSUPP;
3445
3446 /*
3447 * cifs_build_path_to_root works only when we have a valid tcon
3448 */
3449 full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3450 tcon->Flags & SMB_SHARE_IS_IN_DFS);
3451 if (full_path == NULL)
3452 return -ENOMEM;
3453
3454 cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3455
3456 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3457 full_path);
3458 if (rc != 0 && rc != -EREMOTE)
3459 goto out;
3460
3461 if (rc != -EREMOTE) {
3462 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3463 cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3464 if (rc != 0) {
3465 cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3466 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3467 rc = 0;
3468 }
3469 }
3470
3471out:
3472 kfree(full_path);
3473 return rc;
3474}
3475
3476#ifdef CONFIG_CIFS_DFS_UPCALL
3477int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3478{
3479 struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3480 bool isdfs;
3481 int rc;
3482
3483 uuid_gen(&mnt_ctx.mount_id);
3484 rc = dfs_mount_share(&mnt_ctx, &isdfs);
3485 if (rc)
3486 goto error;
3487 if (!isdfs)
3488 goto out;
3489
3490 /*
3491 * After reconnecting to a different server, unique ids won't match anymore, so we disable
3492 * serverino. This prevents dentry revalidation to think the dentry are stale (ESTALE).
3493 */
3494 cifs_autodisable_serverino(cifs_sb);
3495 /*
3496 * Force the use of prefix path to support failover on DFS paths that resolve to targets
3497 * that have different prefix paths.
3498 */
3499 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3500 kfree(cifs_sb->prepath);
3501 cifs_sb->prepath = ctx->prepath;
3502 ctx->prepath = NULL;
3503 uuid_copy(&cifs_sb->dfs_mount_id, &mnt_ctx.mount_id);
3504
3505out:
3506 cifs_try_adding_channels(cifs_sb, mnt_ctx.ses);
3507 rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3508 if (rc)
3509 goto error;
3510
3511 free_xid(mnt_ctx.xid);
3512 return rc;
3513
3514error:
3515 dfs_cache_put_refsrv_sessions(&mnt_ctx.mount_id);
3516 kfree(mnt_ctx.origin_fullpath);
3517 kfree(mnt_ctx.leaf_fullpath);
3518 cifs_mount_put_conns(&mnt_ctx);
3519 return rc;
3520}
3521#else
3522int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3523{
3524 int rc = 0;
3525 struct cifs_mount_ctx mnt_ctx = { .cifs_sb = cifs_sb, .fs_ctx = ctx, };
3526
3527 rc = cifs_mount_get_session(&mnt_ctx);
3528 if (rc)
3529 goto error;
3530
3531 rc = cifs_mount_get_tcon(&mnt_ctx);
3532 if (rc)
3533 goto error;
3534
3535 rc = cifs_is_path_remote(&mnt_ctx);
3536 if (rc == -EREMOTE)
3537 rc = -EOPNOTSUPP;
3538 if (rc)
3539 goto error;
3540
3541 rc = mount_setup_tlink(cifs_sb, mnt_ctx.ses, mnt_ctx.tcon);
3542 if (rc)
3543 goto error;
3544
3545 free_xid(mnt_ctx.xid);
3546 return rc;
3547
3548error:
3549 cifs_mount_put_conns(&mnt_ctx);
3550 return rc;
3551}
3552#endif
3553
3554/*
3555 * Issue a TREE_CONNECT request.
3556 */
3557int
3558CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3559 const char *tree, struct cifs_tcon *tcon,
3560 const struct nls_table *nls_codepage)
3561{
3562 struct smb_hdr *smb_buffer;
3563 struct smb_hdr *smb_buffer_response;
3564 TCONX_REQ *pSMB;
3565 TCONX_RSP *pSMBr;
3566 unsigned char *bcc_ptr;
3567 int rc = 0;
3568 int length;
3569 __u16 bytes_left, count;
3570
3571 if (ses == NULL)
3572 return -EIO;
3573
3574 smb_buffer = cifs_buf_get();
3575 if (smb_buffer == NULL)
3576 return -ENOMEM;
3577
3578 smb_buffer_response = smb_buffer;
3579
3580 header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3581 NULL /*no tid */ , 4 /*wct */ );
3582
3583 smb_buffer->Mid = get_next_mid(ses->server);
3584 smb_buffer->Uid = ses->Suid;
3585 pSMB = (TCONX_REQ *) smb_buffer;
3586 pSMBr = (TCONX_RSP *) smb_buffer_response;
3587
3588 pSMB->AndXCommand = 0xFF;
3589 pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3590 bcc_ptr = &pSMB->Password[0];
3591
3592 pSMB->PasswordLength = cpu_to_le16(1); /* minimum */
3593 *bcc_ptr = 0; /* password is null byte */
3594 bcc_ptr++; /* skip password */
3595 /* already aligned so no need to do it below */
3596
3597 if (ses->server->sign)
3598 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3599
3600 if (ses->capabilities & CAP_STATUS32) {
3601 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3602 }
3603 if (ses->capabilities & CAP_DFS) {
3604 smb_buffer->Flags2 |= SMBFLG2_DFS;
3605 }
3606 if (ses->capabilities & CAP_UNICODE) {
3607 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3608 length =
3609 cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3610 6 /* max utf8 char length in bytes */ *
3611 (/* server len*/ + 256 /* share len */), nls_codepage);
3612 bcc_ptr += 2 * length; /* convert num 16 bit words to bytes */
3613 bcc_ptr += 2; /* skip trailing null */
3614 } else { /* ASCII */
3615 strcpy(bcc_ptr, tree);
3616 bcc_ptr += strlen(tree) + 1;
3617 }
3618 strcpy(bcc_ptr, "?????");
3619 bcc_ptr += strlen("?????");
3620 bcc_ptr += 1;
3621 count = bcc_ptr - &pSMB->Password[0];
3622 be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3623 pSMB->ByteCount = cpu_to_le16(count);
3624
3625 rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3626 0);
3627
3628 /* above now done in SendReceive */
3629 if (rc == 0) {
3630 bool is_unicode;
3631
3632 tcon->tid = smb_buffer_response->Tid;
3633 bcc_ptr = pByteArea(smb_buffer_response);
3634 bytes_left = get_bcc(smb_buffer_response);
3635 length = strnlen(bcc_ptr, bytes_left - 2);
3636 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3637 is_unicode = true;
3638 else
3639 is_unicode = false;
3640
3641
3642 /* skip service field (NB: this field is always ASCII) */
3643 if (length == 3) {
3644 if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3645 (bcc_ptr[2] == 'C')) {
3646 cifs_dbg(FYI, "IPC connection\n");
3647 tcon->ipc = true;
3648 tcon->pipe = true;
3649 }
3650 } else if (length == 2) {
3651 if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3652 /* the most common case */
3653 cifs_dbg(FYI, "disk share connection\n");
3654 }
3655 }
3656 bcc_ptr += length + 1;
3657 bytes_left -= (length + 1);
3658 strscpy(tcon->tree_name, tree, sizeof(tcon->tree_name));
3659
3660 /* mostly informational -- no need to fail on error here */
3661 kfree(tcon->nativeFileSystem);
3662 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3663 bytes_left, is_unicode,
3664 nls_codepage);
3665
3666 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3667
3668 if ((smb_buffer_response->WordCount == 3) ||
3669 (smb_buffer_response->WordCount == 7))
3670 /* field is in same location */
3671 tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3672 else
3673 tcon->Flags = 0;
3674 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3675 }
3676
3677 cifs_buf_release(smb_buffer);
3678 return rc;
3679}
3680
3681static void delayed_free(struct rcu_head *p)
3682{
3683 struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3684
3685 unload_nls(cifs_sb->local_nls);
3686 smb3_cleanup_fs_context(cifs_sb->ctx);
3687 kfree(cifs_sb);
3688}
3689
3690void
3691cifs_umount(struct cifs_sb_info *cifs_sb)
3692{
3693 struct rb_root *root = &cifs_sb->tlink_tree;
3694 struct rb_node *node;
3695 struct tcon_link *tlink;
3696
3697 cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3698
3699 spin_lock(&cifs_sb->tlink_tree_lock);
3700 while ((node = rb_first(root))) {
3701 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3702 cifs_get_tlink(tlink);
3703 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3704 rb_erase(node, root);
3705
3706 spin_unlock(&cifs_sb->tlink_tree_lock);
3707 cifs_put_tlink(tlink);
3708 spin_lock(&cifs_sb->tlink_tree_lock);
3709 }
3710 spin_unlock(&cifs_sb->tlink_tree_lock);
3711
3712 kfree(cifs_sb->prepath);
3713#ifdef CONFIG_CIFS_DFS_UPCALL
3714 dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
3715#endif
3716 call_rcu(&cifs_sb->rcu, delayed_free);
3717}
3718
3719int
3720cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses,
3721 struct TCP_Server_Info *server)
3722{
3723 int rc = 0;
3724
3725 if (!server->ops->need_neg || !server->ops->negotiate)
3726 return -ENOSYS;
3727
3728 /* only send once per connect */
3729 spin_lock(&server->srv_lock);
3730 if (!server->ops->need_neg(server) ||
3731 server->tcpStatus != CifsNeedNegotiate) {
3732 spin_unlock(&server->srv_lock);
3733 return 0;
3734 }
3735 server->tcpStatus = CifsInNegotiate;
3736 spin_unlock(&server->srv_lock);
3737
3738 rc = server->ops->negotiate(xid, ses, server);
3739 if (rc == 0) {
3740 spin_lock(&server->srv_lock);
3741 if (server->tcpStatus == CifsInNegotiate)
3742 server->tcpStatus = CifsGood;
3743 else
3744 rc = -EHOSTDOWN;
3745 spin_unlock(&server->srv_lock);
3746 } else {
3747 spin_lock(&server->srv_lock);
3748 if (server->tcpStatus == CifsInNegotiate)
3749 server->tcpStatus = CifsNeedNegotiate;
3750 spin_unlock(&server->srv_lock);
3751 }
3752
3753 return rc;
3754}
3755
3756int
3757cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3758 struct TCP_Server_Info *server,
3759 struct nls_table *nls_info)
3760{
3761 int rc = -ENOSYS;
3762 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
3763 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
3764 bool is_binding = false;
3765
3766 spin_lock(&ses->ses_lock);
3767 if (server->dstaddr.ss_family == AF_INET6)
3768 scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI6", &addr6->sin6_addr);
3769 else
3770 scnprintf(ses->ip_addr, sizeof(ses->ip_addr), "%pI4", &addr->sin_addr);
3771
3772 if (ses->ses_status != SES_GOOD &&
3773 ses->ses_status != SES_NEW &&
3774 ses->ses_status != SES_NEED_RECON) {
3775 spin_unlock(&ses->ses_lock);
3776 return 0;
3777 }
3778
3779 /* only send once per connect */
3780 spin_lock(&ses->chan_lock);
3781 if (CIFS_ALL_CHANS_GOOD(ses) ||
3782 cifs_chan_in_reconnect(ses, server)) {
3783 spin_unlock(&ses->chan_lock);
3784 spin_unlock(&ses->ses_lock);
3785 return 0;
3786 }
3787 is_binding = !CIFS_ALL_CHANS_NEED_RECONNECT(ses);
3788 cifs_chan_set_in_reconnect(ses, server);
3789 spin_unlock(&ses->chan_lock);
3790
3791 if (!is_binding)
3792 ses->ses_status = SES_IN_SETUP;
3793 spin_unlock(&ses->ses_lock);
3794
3795 if (!is_binding) {
3796 ses->capabilities = server->capabilities;
3797 if (!linuxExtEnabled)
3798 ses->capabilities &= (~server->vals->cap_unix);
3799
3800 if (ses->auth_key.response) {
3801 cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3802 ses->auth_key.response);
3803 kfree_sensitive(ses->auth_key.response);
3804 ses->auth_key.response = NULL;
3805 ses->auth_key.len = 0;
3806 }
3807 }
3808
3809 cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3810 server->sec_mode, server->capabilities, server->timeAdj);
3811
3812 if (server->ops->sess_setup)
3813 rc = server->ops->sess_setup(xid, ses, server, nls_info);
3814
3815 if (rc) {
3816 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3817 spin_lock(&ses->ses_lock);
3818 if (ses->ses_status == SES_IN_SETUP)
3819 ses->ses_status = SES_NEED_RECON;
3820 spin_lock(&ses->chan_lock);
3821 cifs_chan_clear_in_reconnect(ses, server);
3822 spin_unlock(&ses->chan_lock);
3823 spin_unlock(&ses->ses_lock);
3824 } else {
3825 spin_lock(&ses->ses_lock);
3826 if (ses->ses_status == SES_IN_SETUP)
3827 ses->ses_status = SES_GOOD;
3828 spin_lock(&ses->chan_lock);
3829 cifs_chan_clear_in_reconnect(ses, server);
3830 cifs_chan_clear_need_reconnect(ses, server);
3831 spin_unlock(&ses->chan_lock);
3832 spin_unlock(&ses->ses_lock);
3833 }
3834
3835 return rc;
3836}
3837
3838static int
3839cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3840{
3841 ctx->sectype = ses->sectype;
3842
3843 /* krb5 is special, since we don't need username or pw */
3844 if (ctx->sectype == Kerberos)
3845 return 0;
3846
3847 return cifs_set_cifscreds(ctx, ses);
3848}
3849
3850static struct cifs_tcon *
3851cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3852{
3853 int rc;
3854 struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3855 struct cifs_ses *ses;
3856 struct cifs_tcon *tcon = NULL;
3857 struct smb3_fs_context *ctx;
3858
3859 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3860 if (ctx == NULL)
3861 return ERR_PTR(-ENOMEM);
3862
3863 ctx->local_nls = cifs_sb->local_nls;
3864 ctx->linux_uid = fsuid;
3865 ctx->cred_uid = fsuid;
3866 ctx->UNC = master_tcon->tree_name;
3867 ctx->retry = master_tcon->retry;
3868 ctx->nocase = master_tcon->nocase;
3869 ctx->nohandlecache = master_tcon->nohandlecache;
3870 ctx->local_lease = master_tcon->local_lease;
3871 ctx->no_lease = master_tcon->no_lease;
3872 ctx->resilient = master_tcon->use_resilient;
3873 ctx->persistent = master_tcon->use_persistent;
3874 ctx->handle_timeout = master_tcon->handle_timeout;
3875 ctx->no_linux_ext = !master_tcon->unix_ext;
3876 ctx->linux_ext = master_tcon->posix_extensions;
3877 ctx->sectype = master_tcon->ses->sectype;
3878 ctx->sign = master_tcon->ses->sign;
3879 ctx->seal = master_tcon->seal;
3880 ctx->witness = master_tcon->use_witness;
3881
3882 rc = cifs_set_vol_auth(ctx, master_tcon->ses);
3883 if (rc) {
3884 tcon = ERR_PTR(rc);
3885 goto out;
3886 }
3887
3888 /* get a reference for the same TCP session */
3889 spin_lock(&cifs_tcp_ses_lock);
3890 ++master_tcon->ses->server->srv_count;
3891 spin_unlock(&cifs_tcp_ses_lock);
3892
3893 ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
3894 if (IS_ERR(ses)) {
3895 tcon = (struct cifs_tcon *)ses;
3896 cifs_put_tcp_session(master_tcon->ses->server, 0);
3897 goto out;
3898 }
3899
3900 tcon = cifs_get_tcon(ses, ctx);
3901 if (IS_ERR(tcon)) {
3902 cifs_put_smb_ses(ses);
3903 goto out;
3904 }
3905
3906#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
3907 if (cap_unix(ses))
3908 reset_cifs_unix_caps(0, tcon, NULL, ctx);
3909#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
3910
3911out:
3912 kfree(ctx->username);
3913 kfree_sensitive(ctx->password);
3914 kfree(ctx);
3915
3916 return tcon;
3917}
3918
3919struct cifs_tcon *
3920cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
3921{
3922 return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
3923}
3924
3925/* find and return a tlink with given uid */
3926static struct tcon_link *
3927tlink_rb_search(struct rb_root *root, kuid_t uid)
3928{
3929 struct rb_node *node = root->rb_node;
3930 struct tcon_link *tlink;
3931
3932 while (node) {
3933 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3934
3935 if (uid_gt(tlink->tl_uid, uid))
3936 node = node->rb_left;
3937 else if (uid_lt(tlink->tl_uid, uid))
3938 node = node->rb_right;
3939 else
3940 return tlink;
3941 }
3942 return NULL;
3943}
3944
3945/* insert a tcon_link into the tree */
3946static void
3947tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
3948{
3949 struct rb_node **new = &(root->rb_node), *parent = NULL;
3950 struct tcon_link *tlink;
3951
3952 while (*new) {
3953 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
3954 parent = *new;
3955
3956 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
3957 new = &((*new)->rb_left);
3958 else
3959 new = &((*new)->rb_right);
3960 }
3961
3962 rb_link_node(&new_tlink->tl_rbnode, parent, new);
3963 rb_insert_color(&new_tlink->tl_rbnode, root);
3964}
3965
3966/*
3967 * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
3968 * current task.
3969 *
3970 * If the superblock doesn't refer to a multiuser mount, then just return
3971 * the master tcon for the mount.
3972 *
3973 * First, search the rbtree for an existing tcon for this fsuid. If one
3974 * exists, then check to see if it's pending construction. If it is then wait
3975 * for construction to complete. Once it's no longer pending, check to see if
3976 * it failed and either return an error or retry construction, depending on
3977 * the timeout.
3978 *
3979 * If one doesn't exist then insert a new tcon_link struct into the tree and
3980 * try to construct a new one.
3981 */
3982struct tcon_link *
3983cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
3984{
3985 int ret;
3986 kuid_t fsuid = current_fsuid();
3987 struct tcon_link *tlink, *newtlink;
3988
3989 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
3990 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
3991
3992 spin_lock(&cifs_sb->tlink_tree_lock);
3993 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
3994 if (tlink)
3995 cifs_get_tlink(tlink);
3996 spin_unlock(&cifs_sb->tlink_tree_lock);
3997
3998 if (tlink == NULL) {
3999 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4000 if (newtlink == NULL)
4001 return ERR_PTR(-ENOMEM);
4002 newtlink->tl_uid = fsuid;
4003 newtlink->tl_tcon = ERR_PTR(-EACCES);
4004 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4005 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4006 cifs_get_tlink(newtlink);
4007
4008 spin_lock(&cifs_sb->tlink_tree_lock);
4009 /* was one inserted after previous search? */
4010 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4011 if (tlink) {
4012 cifs_get_tlink(tlink);
4013 spin_unlock(&cifs_sb->tlink_tree_lock);
4014 kfree(newtlink);
4015 goto wait_for_construction;
4016 }
4017 tlink = newtlink;
4018 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4019 spin_unlock(&cifs_sb->tlink_tree_lock);
4020 } else {
4021wait_for_construction:
4022 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4023 TASK_INTERRUPTIBLE);
4024 if (ret) {
4025 cifs_put_tlink(tlink);
4026 return ERR_PTR(-ERESTARTSYS);
4027 }
4028
4029 /* if it's good, return it */
4030 if (!IS_ERR(tlink->tl_tcon))
4031 return tlink;
4032
4033 /* return error if we tried this already recently */
4034 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4035 cifs_put_tlink(tlink);
4036 return ERR_PTR(-EACCES);
4037 }
4038
4039 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4040 goto wait_for_construction;
4041 }
4042
4043 tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4044 clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4045 wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4046
4047 if (IS_ERR(tlink->tl_tcon)) {
4048 cifs_put_tlink(tlink);
4049 return ERR_PTR(-EACCES);
4050 }
4051
4052 return tlink;
4053}
4054
4055/*
4056 * periodic workqueue job that scans tcon_tree for a superblock and closes
4057 * out tcons.
4058 */
4059static void
4060cifs_prune_tlinks(struct work_struct *work)
4061{
4062 struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4063 prune_tlinks.work);
4064 struct rb_root *root = &cifs_sb->tlink_tree;
4065 struct rb_node *node;
4066 struct rb_node *tmp;
4067 struct tcon_link *tlink;
4068
4069 /*
4070 * Because we drop the spinlock in the loop in order to put the tlink
4071 * it's not guarded against removal of links from the tree. The only
4072 * places that remove entries from the tree are this function and
4073 * umounts. Because this function is non-reentrant and is canceled
4074 * before umount can proceed, this is safe.
4075 */
4076 spin_lock(&cifs_sb->tlink_tree_lock);
4077 node = rb_first(root);
4078 while (node != NULL) {
4079 tmp = node;
4080 node = rb_next(tmp);
4081 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4082
4083 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4084 atomic_read(&tlink->tl_count) != 0 ||
4085 time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4086 continue;
4087
4088 cifs_get_tlink(tlink);
4089 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4090 rb_erase(tmp, root);
4091
4092 spin_unlock(&cifs_sb->tlink_tree_lock);
4093 cifs_put_tlink(tlink);
4094 spin_lock(&cifs_sb->tlink_tree_lock);
4095 }
4096 spin_unlock(&cifs_sb->tlink_tree_lock);
4097
4098 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4099 TLINK_IDLE_EXPIRE);
4100}
4101
4102#ifndef CONFIG_CIFS_DFS_UPCALL
4103int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4104{
4105 int rc;
4106 const struct smb_version_operations *ops = tcon->ses->server->ops;
4107
4108 /* only send once per connect */
4109 spin_lock(&tcon->tc_lock);
4110 if (tcon->ses->ses_status != SES_GOOD ||
4111 (tcon->status != TID_NEW &&
4112 tcon->status != TID_NEED_TCON)) {
4113 spin_unlock(&tcon->tc_lock);
4114 return 0;
4115 }
4116 tcon->status = TID_IN_TCON;
4117 spin_unlock(&tcon->tc_lock);
4118
4119 rc = ops->tree_connect(xid, tcon->ses, tcon->tree_name, tcon, nlsc);
4120 if (rc) {
4121 spin_lock(&tcon->tc_lock);
4122 if (tcon->status == TID_IN_TCON)
4123 tcon->status = TID_NEED_TCON;
4124 spin_unlock(&tcon->tc_lock);
4125 } else {
4126 spin_lock(&tcon->tc_lock);
4127 if (tcon->status == TID_IN_TCON)
4128 tcon->status = TID_GOOD;
4129 tcon->need_reconnect = false;
4130 spin_unlock(&tcon->tc_lock);
4131 }
4132
4133 return rc;
4134}
4135#endif
1// SPDX-License-Identifier: LGPL-2.1
2/*
3 * fs/cifs/connect.c
4 *
5 * Copyright (C) International Business Machines Corp., 2002,2011
6 * Author(s): Steve French (sfrench@us.ibm.com)
7 *
8 */
9#include <linux/fs.h>
10#include <linux/net.h>
11#include <linux/string.h>
12#include <linux/sched/mm.h>
13#include <linux/sched/signal.h>
14#include <linux/list.h>
15#include <linux/wait.h>
16#include <linux/slab.h>
17#include <linux/pagemap.h>
18#include <linux/ctype.h>
19#include <linux/utsname.h>
20#include <linux/mempool.h>
21#include <linux/delay.h>
22#include <linux/completion.h>
23#include <linux/kthread.h>
24#include <linux/pagevec.h>
25#include <linux/freezer.h>
26#include <linux/namei.h>
27#include <linux/uuid.h>
28#include <linux/uaccess.h>
29#include <asm/processor.h>
30#include <linux/inet.h>
31#include <linux/module.h>
32#include <keys/user-type.h>
33#include <net/ipv6.h>
34#include <linux/parser.h>
35#include <linux/bvec.h>
36#include "cifspdu.h"
37#include "cifsglob.h"
38#include "cifsproto.h"
39#include "cifs_unicode.h"
40#include "cifs_debug.h"
41#include "cifs_fs_sb.h"
42#include "ntlmssp.h"
43#include "nterr.h"
44#include "rfc1002pdu.h"
45#include "fscache.h"
46#include "smb2proto.h"
47#include "smbdirect.h"
48#include "dns_resolve.h"
49#ifdef CONFIG_CIFS_DFS_UPCALL
50#include "dfs_cache.h"
51#endif
52#include "fs_context.h"
53#include "cifs_swn.h"
54
55extern mempool_t *cifs_req_poolp;
56extern 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 NUM_STATUS_IO_TIMEOUT 5
64
65static int ip_connect(struct TCP_Server_Info *server);
66static int generic_ip_connect(struct TCP_Server_Info *server);
67static void tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink);
68static 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 */
76static int reconn_set_ipaddr_from_hostname(struct TCP_Server_Info *server)
77{
78 int rc;
79 int len;
80 char *unc, *ipaddr = NULL;
81 time64_t expiry, now;
82 unsigned long ttl = SMB_DNS_RESOLVE_INTERVAL_DEFAULT;
83
84 if (!server->hostname)
85 return -EINVAL;
86
87 len = strlen(server->hostname) + 3;
88
89 unc = kmalloc(len, GFP_KERNEL);
90 if (!unc) {
91 cifs_dbg(FYI, "%s: failed to create UNC path\n", __func__);
92 return -ENOMEM;
93 }
94 scnprintf(unc, len, "\\\\%s", server->hostname);
95
96 rc = dns_resolve_server_name_to_ip(unc, &ipaddr, &expiry);
97 kfree(unc);
98
99 if (rc < 0) {
100 cifs_dbg(FYI, "%s: failed to resolve server part of %s to IP: %d\n",
101 __func__, server->hostname, rc);
102 goto requeue_resolve;
103 }
104
105 spin_lock(&cifs_tcp_ses_lock);
106 rc = cifs_convert_address((struct sockaddr *)&server->dstaddr, ipaddr,
107 strlen(ipaddr));
108 spin_unlock(&cifs_tcp_ses_lock);
109 kfree(ipaddr);
110
111 /* rc == 1 means success here */
112 if (rc) {
113 now = ktime_get_real_seconds();
114 if (expiry && expiry > now)
115 /*
116 * To make sure we don't use the cached entry, retry 1s
117 * after expiry.
118 */
119 ttl = (expiry - now + 1);
120 }
121 rc = !rc ? -1 : 0;
122
123requeue_resolve:
124 cifs_dbg(FYI, "%s: next dns resolution scheduled for %lu seconds in the future\n",
125 __func__, ttl);
126 mod_delayed_work(cifsiod_wq, &server->resolve, (ttl * HZ));
127
128 return rc;
129}
130
131
132static void cifs_resolve_server(struct work_struct *work)
133{
134 int rc;
135 struct TCP_Server_Info *server = container_of(work,
136 struct TCP_Server_Info, resolve.work);
137
138 mutex_lock(&server->srv_mutex);
139
140 /*
141 * Resolve the hostname again to make sure that IP address is up-to-date.
142 */
143 rc = reconn_set_ipaddr_from_hostname(server);
144 if (rc) {
145 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
146 __func__, rc);
147 }
148
149 mutex_unlock(&server->srv_mutex);
150}
151
152#ifdef CONFIG_CIFS_DFS_UPCALL
153/* These functions must be called with server->srv_mutex held */
154static void reconn_set_next_dfs_target(struct TCP_Server_Info *server,
155 struct cifs_sb_info *cifs_sb,
156 struct dfs_cache_tgt_list *tgt_list,
157 struct dfs_cache_tgt_iterator **tgt_it)
158{
159 const char *name;
160 int rc;
161
162 if (!cifs_sb || !cifs_sb->origin_fullpath)
163 return;
164
165 if (!*tgt_it) {
166 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
167 } else {
168 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
169 if (!*tgt_it)
170 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
171 }
172
173 cifs_dbg(FYI, "%s: UNC: %s\n", __func__, cifs_sb->origin_fullpath);
174
175 name = dfs_cache_get_tgt_name(*tgt_it);
176
177 kfree(server->hostname);
178
179 server->hostname = extract_hostname(name);
180 if (IS_ERR(server->hostname)) {
181 cifs_dbg(FYI,
182 "%s: failed to extract hostname from target: %ld\n",
183 __func__, PTR_ERR(server->hostname));
184 return;
185 }
186
187 rc = reconn_set_ipaddr_from_hostname(server);
188 if (rc) {
189 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
190 __func__, rc);
191 }
192}
193
194static inline int reconn_setup_dfs_targets(struct cifs_sb_info *cifs_sb,
195 struct dfs_cache_tgt_list *tl)
196{
197 if (!cifs_sb->origin_fullpath)
198 return -EOPNOTSUPP;
199 return dfs_cache_noreq_find(cifs_sb->origin_fullpath + 1, NULL, tl);
200}
201#endif
202
203/*
204 * cifs tcp session reconnection
205 *
206 * mark tcp session as reconnecting so temporarily locked
207 * mark all smb sessions as reconnecting for tcp session
208 * reconnect tcp session
209 * wake up waiters on reconnection? - (not needed currently)
210 */
211int
212cifs_reconnect(struct TCP_Server_Info *server)
213{
214 int rc = 0;
215 struct list_head *tmp, *tmp2;
216 struct cifs_ses *ses;
217 struct cifs_tcon *tcon;
218 struct mid_q_entry *mid_entry;
219 struct list_head retry_list;
220#ifdef CONFIG_CIFS_DFS_UPCALL
221 struct super_block *sb = NULL;
222 struct cifs_sb_info *cifs_sb = NULL;
223 struct dfs_cache_tgt_list tgt_list = DFS_CACHE_TGT_LIST_INIT(tgt_list);
224 struct dfs_cache_tgt_iterator *tgt_it = NULL;
225#endif
226
227 spin_lock(&GlobalMid_Lock);
228 server->nr_targets = 1;
229#ifdef CONFIG_CIFS_DFS_UPCALL
230 spin_unlock(&GlobalMid_Lock);
231 sb = cifs_get_tcp_super(server);
232 if (IS_ERR(sb)) {
233 rc = PTR_ERR(sb);
234 cifs_dbg(FYI, "%s: will not do DFS failover: rc = %d\n",
235 __func__, rc);
236 sb = NULL;
237 } else {
238 cifs_sb = CIFS_SB(sb);
239 rc = reconn_setup_dfs_targets(cifs_sb, &tgt_list);
240 if (rc) {
241 cifs_sb = NULL;
242 if (rc != -EOPNOTSUPP) {
243 cifs_server_dbg(VFS, "%s: no target servers for DFS failover\n",
244 __func__);
245 }
246 } else {
247 server->nr_targets = dfs_cache_get_nr_tgts(&tgt_list);
248 }
249 }
250 cifs_dbg(FYI, "%s: will retry %d target(s)\n", __func__,
251 server->nr_targets);
252 spin_lock(&GlobalMid_Lock);
253#endif
254 if (server->tcpStatus == CifsExiting) {
255 /* the demux thread will exit normally
256 next time through the loop */
257 spin_unlock(&GlobalMid_Lock);
258#ifdef CONFIG_CIFS_DFS_UPCALL
259 dfs_cache_free_tgts(&tgt_list);
260 cifs_put_tcp_super(sb);
261#endif
262 wake_up(&server->response_q);
263 return rc;
264 } else
265 server->tcpStatus = CifsNeedReconnect;
266 spin_unlock(&GlobalMid_Lock);
267 server->maxBuf = 0;
268 server->max_read = 0;
269
270 cifs_dbg(FYI, "Mark tcp session as need reconnect\n");
271 trace_smb3_reconnect(server->CurrentMid, server->conn_id, server->hostname);
272
273 /* before reconnecting the tcp session, mark the smb session (uid)
274 and the tid bad so they are not used until reconnected */
275 cifs_dbg(FYI, "%s: marking sessions and tcons for reconnect\n",
276 __func__);
277 spin_lock(&cifs_tcp_ses_lock);
278 list_for_each(tmp, &server->smb_ses_list) {
279 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
280 ses->need_reconnect = true;
281 list_for_each(tmp2, &ses->tcon_list) {
282 tcon = list_entry(tmp2, struct cifs_tcon, tcon_list);
283 tcon->need_reconnect = true;
284 }
285 if (ses->tcon_ipc)
286 ses->tcon_ipc->need_reconnect = true;
287 }
288 spin_unlock(&cifs_tcp_ses_lock);
289
290 /* do not want to be sending data on a socket we are freeing */
291 cifs_dbg(FYI, "%s: tearing down socket\n", __func__);
292 mutex_lock(&server->srv_mutex);
293 if (server->ssocket) {
294 cifs_dbg(FYI, "State: 0x%x Flags: 0x%lx\n",
295 server->ssocket->state, server->ssocket->flags);
296 kernel_sock_shutdown(server->ssocket, SHUT_WR);
297 cifs_dbg(FYI, "Post shutdown state: 0x%x Flags: 0x%lx\n",
298 server->ssocket->state, server->ssocket->flags);
299 sock_release(server->ssocket);
300 server->ssocket = NULL;
301 }
302 server->sequence_number = 0;
303 server->session_estab = false;
304 kfree(server->session_key.response);
305 server->session_key.response = NULL;
306 server->session_key.len = 0;
307 server->lstrp = jiffies;
308
309 /* mark submitted MIDs for retry and issue callback */
310 INIT_LIST_HEAD(&retry_list);
311 cifs_dbg(FYI, "%s: moving mids to private list\n", __func__);
312 spin_lock(&GlobalMid_Lock);
313 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
314 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
315 kref_get(&mid_entry->refcount);
316 if (mid_entry->mid_state == MID_REQUEST_SUBMITTED)
317 mid_entry->mid_state = MID_RETRY_NEEDED;
318 list_move(&mid_entry->qhead, &retry_list);
319 mid_entry->mid_flags |= MID_DELETED;
320 }
321 spin_unlock(&GlobalMid_Lock);
322 mutex_unlock(&server->srv_mutex);
323
324 cifs_dbg(FYI, "%s: issuing mid callbacks\n", __func__);
325 list_for_each_safe(tmp, tmp2, &retry_list) {
326 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
327 list_del_init(&mid_entry->qhead);
328 mid_entry->callback(mid_entry);
329 cifs_mid_q_entry_release(mid_entry);
330 }
331
332 if (cifs_rdma_enabled(server)) {
333 mutex_lock(&server->srv_mutex);
334 smbd_destroy(server);
335 mutex_unlock(&server->srv_mutex);
336 }
337
338 do {
339 try_to_freeze();
340
341 mutex_lock(&server->srv_mutex);
342
343
344 if (!cifs_swn_set_server_dstaddr(server)) {
345#ifdef CONFIG_CIFS_DFS_UPCALL
346 if (cifs_sb && cifs_sb->origin_fullpath)
347 /*
348 * Set up next DFS target server (if any) for reconnect. If DFS
349 * feature is disabled, then we will retry last server we
350 * connected to before.
351 */
352 reconn_set_next_dfs_target(server, cifs_sb, &tgt_list, &tgt_it);
353 else {
354#endif
355 /*
356 * Resolve the hostname again to make sure that IP address is up-to-date.
357 */
358 rc = reconn_set_ipaddr_from_hostname(server);
359 if (rc) {
360 cifs_dbg(FYI, "%s: failed to resolve hostname: %d\n",
361 __func__, rc);
362 }
363
364#ifdef CONFIG_CIFS_DFS_UPCALL
365 }
366#endif
367
368
369 }
370
371 if (cifs_rdma_enabled(server))
372 rc = smbd_reconnect(server);
373 else
374 rc = generic_ip_connect(server);
375 if (rc) {
376 cifs_dbg(FYI, "reconnect error %d\n", rc);
377 mutex_unlock(&server->srv_mutex);
378 msleep(3000);
379 } else {
380 atomic_inc(&tcpSesReconnectCount);
381 set_credits(server, 1);
382 spin_lock(&GlobalMid_Lock);
383 if (server->tcpStatus != CifsExiting)
384 server->tcpStatus = CifsNeedNegotiate;
385 spin_unlock(&GlobalMid_Lock);
386 cifs_swn_reset_server_dstaddr(server);
387 mutex_unlock(&server->srv_mutex);
388 }
389 } while (server->tcpStatus == CifsNeedReconnect);
390
391#ifdef CONFIG_CIFS_DFS_UPCALL
392 if (tgt_it) {
393 rc = dfs_cache_noreq_update_tgthint(cifs_sb->origin_fullpath + 1,
394 tgt_it);
395 if (rc) {
396 cifs_server_dbg(VFS, "%s: failed to update DFS target hint: rc = %d\n",
397 __func__, rc);
398 }
399 dfs_cache_free_tgts(&tgt_list);
400 }
401
402 cifs_put_tcp_super(sb);
403#endif
404 if (server->tcpStatus == CifsNeedNegotiate)
405 mod_delayed_work(cifsiod_wq, &server->echo, 0);
406
407 wake_up(&server->response_q);
408 return rc;
409}
410
411static void
412cifs_echo_request(struct work_struct *work)
413{
414 int rc;
415 struct TCP_Server_Info *server = container_of(work,
416 struct TCP_Server_Info, echo.work);
417
418 /*
419 * We cannot send an echo if it is disabled.
420 * Also, no need to ping if we got a response recently.
421 */
422
423 if (server->tcpStatus == CifsNeedReconnect ||
424 server->tcpStatus == CifsExiting ||
425 server->tcpStatus == CifsNew ||
426 (server->ops->can_echo && !server->ops->can_echo(server)) ||
427 time_before(jiffies, server->lstrp + server->echo_interval - HZ))
428 goto requeue_echo;
429
430 rc = server->ops->echo ? server->ops->echo(server) : -ENOSYS;
431 if (rc)
432 cifs_dbg(FYI, "Unable to send echo request to server: %s\n",
433 server->hostname);
434
435 /* Check witness registrations */
436 cifs_swn_check();
437
438requeue_echo:
439 queue_delayed_work(cifsiod_wq, &server->echo, server->echo_interval);
440}
441
442static bool
443allocate_buffers(struct TCP_Server_Info *server)
444{
445 if (!server->bigbuf) {
446 server->bigbuf = (char *)cifs_buf_get();
447 if (!server->bigbuf) {
448 cifs_server_dbg(VFS, "No memory for large SMB response\n");
449 msleep(3000);
450 /* retry will check if exiting */
451 return false;
452 }
453 } else if (server->large_buf) {
454 /* we are reusing a dirty large buf, clear its start */
455 memset(server->bigbuf, 0, HEADER_SIZE(server));
456 }
457
458 if (!server->smallbuf) {
459 server->smallbuf = (char *)cifs_small_buf_get();
460 if (!server->smallbuf) {
461 cifs_server_dbg(VFS, "No memory for SMB response\n");
462 msleep(1000);
463 /* retry will check if exiting */
464 return false;
465 }
466 /* beginning of smb buffer is cleared in our buf_get */
467 } else {
468 /* if existing small buf clear beginning */
469 memset(server->smallbuf, 0, HEADER_SIZE(server));
470 }
471
472 return true;
473}
474
475static bool
476server_unresponsive(struct TCP_Server_Info *server)
477{
478 /*
479 * We need to wait 3 echo intervals to make sure we handle such
480 * situations right:
481 * 1s client sends a normal SMB request
482 * 2s client gets a response
483 * 30s echo workqueue job pops, and decides we got a response recently
484 * and don't need to send another
485 * ...
486 * 65s kernel_recvmsg times out, and we see that we haven't gotten
487 * a response in >60s.
488 */
489 if ((server->tcpStatus == CifsGood ||
490 server->tcpStatus == CifsNeedNegotiate) &&
491 (!server->ops->can_echo || server->ops->can_echo(server)) &&
492 time_after(jiffies, server->lstrp + 3 * server->echo_interval)) {
493 cifs_server_dbg(VFS, "has not responded in %lu seconds. Reconnecting...\n",
494 (3 * server->echo_interval) / HZ);
495 cifs_reconnect(server);
496 return true;
497 }
498
499 return false;
500}
501
502static inline bool
503zero_credits(struct TCP_Server_Info *server)
504{
505 int val;
506
507 spin_lock(&server->req_lock);
508 val = server->credits + server->echo_credits + server->oplock_credits;
509 if (server->in_flight == 0 && val == 0) {
510 spin_unlock(&server->req_lock);
511 return true;
512 }
513 spin_unlock(&server->req_lock);
514 return false;
515}
516
517static int
518cifs_readv_from_socket(struct TCP_Server_Info *server, struct msghdr *smb_msg)
519{
520 int length = 0;
521 int total_read;
522
523 smb_msg->msg_control = NULL;
524 smb_msg->msg_controllen = 0;
525
526 for (total_read = 0; msg_data_left(smb_msg); total_read += length) {
527 try_to_freeze();
528
529 /* reconnect if no credits and no requests in flight */
530 if (zero_credits(server)) {
531 cifs_reconnect(server);
532 return -ECONNABORTED;
533 }
534
535 if (server_unresponsive(server))
536 return -ECONNABORTED;
537 if (cifs_rdma_enabled(server) && server->smbd_conn)
538 length = smbd_recv(server->smbd_conn, smb_msg);
539 else
540 length = sock_recvmsg(server->ssocket, smb_msg, 0);
541
542 if (server->tcpStatus == CifsExiting)
543 return -ESHUTDOWN;
544
545 if (server->tcpStatus == CifsNeedReconnect) {
546 cifs_reconnect(server);
547 return -ECONNABORTED;
548 }
549
550 if (length == -ERESTARTSYS ||
551 length == -EAGAIN ||
552 length == -EINTR) {
553 /*
554 * Minimum sleep to prevent looping, allowing socket
555 * to clear and app threads to set tcpStatus
556 * CifsNeedReconnect if server hung.
557 */
558 usleep_range(1000, 2000);
559 length = 0;
560 continue;
561 }
562
563 if (length <= 0) {
564 cifs_dbg(FYI, "Received no data or error: %d\n", length);
565 cifs_reconnect(server);
566 return -ECONNABORTED;
567 }
568 }
569 return total_read;
570}
571
572int
573cifs_read_from_socket(struct TCP_Server_Info *server, char *buf,
574 unsigned int to_read)
575{
576 struct msghdr smb_msg;
577 struct kvec iov = {.iov_base = buf, .iov_len = to_read};
578 iov_iter_kvec(&smb_msg.msg_iter, READ, &iov, 1, to_read);
579
580 return cifs_readv_from_socket(server, &smb_msg);
581}
582
583ssize_t
584cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read)
585{
586 struct msghdr smb_msg;
587
588 /*
589 * iov_iter_discard already sets smb_msg.type and count and iov_offset
590 * and cifs_readv_from_socket sets msg_control and msg_controllen
591 * so little to initialize in struct msghdr
592 */
593 smb_msg.msg_name = NULL;
594 smb_msg.msg_namelen = 0;
595 iov_iter_discard(&smb_msg.msg_iter, READ, to_read);
596
597 return cifs_readv_from_socket(server, &smb_msg);
598}
599
600int
601cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page,
602 unsigned int page_offset, unsigned int to_read)
603{
604 struct msghdr smb_msg;
605 struct bio_vec bv = {
606 .bv_page = page, .bv_len = to_read, .bv_offset = page_offset};
607 iov_iter_bvec(&smb_msg.msg_iter, READ, &bv, 1, to_read);
608 return cifs_readv_from_socket(server, &smb_msg);
609}
610
611static bool
612is_smb_response(struct TCP_Server_Info *server, unsigned char type)
613{
614 /*
615 * The first byte big endian of the length field,
616 * is actually not part of the length but the type
617 * with the most common, zero, as regular data.
618 */
619 switch (type) {
620 case RFC1002_SESSION_MESSAGE:
621 /* Regular SMB response */
622 return true;
623 case RFC1002_SESSION_KEEP_ALIVE:
624 cifs_dbg(FYI, "RFC 1002 session keep alive\n");
625 break;
626 case RFC1002_POSITIVE_SESSION_RESPONSE:
627 cifs_dbg(FYI, "RFC 1002 positive session response\n");
628 break;
629 case RFC1002_NEGATIVE_SESSION_RESPONSE:
630 /*
631 * We get this from Windows 98 instead of an error on
632 * SMB negprot response.
633 */
634 cifs_dbg(FYI, "RFC 1002 negative session response\n");
635 /* give server a second to clean up */
636 msleep(1000);
637 /*
638 * Always try 445 first on reconnect since we get NACK
639 * on some if we ever connected to port 139 (the NACK
640 * is since we do not begin with RFC1001 session
641 * initialize frame).
642 */
643 cifs_set_port((struct sockaddr *)&server->dstaddr, CIFS_PORT);
644 cifs_reconnect(server);
645 break;
646 default:
647 cifs_server_dbg(VFS, "RFC 1002 unknown response type 0x%x\n", type);
648 cifs_reconnect(server);
649 }
650
651 return false;
652}
653
654void
655dequeue_mid(struct mid_q_entry *mid, bool malformed)
656{
657#ifdef CONFIG_CIFS_STATS2
658 mid->when_received = jiffies;
659#endif
660 spin_lock(&GlobalMid_Lock);
661 if (!malformed)
662 mid->mid_state = MID_RESPONSE_RECEIVED;
663 else
664 mid->mid_state = MID_RESPONSE_MALFORMED;
665 /*
666 * Trying to handle/dequeue a mid after the send_recv()
667 * function has finished processing it is a bug.
668 */
669 if (mid->mid_flags & MID_DELETED)
670 pr_warn_once("trying to dequeue a deleted mid\n");
671 else {
672 list_del_init(&mid->qhead);
673 mid->mid_flags |= MID_DELETED;
674 }
675 spin_unlock(&GlobalMid_Lock);
676}
677
678static unsigned int
679smb2_get_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
680{
681 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
682
683 /*
684 * SMB1 does not use credits.
685 */
686 if (server->vals->header_preamble_size)
687 return 0;
688
689 return le16_to_cpu(shdr->CreditRequest);
690}
691
692static void
693handle_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server,
694 char *buf, int malformed)
695{
696 if (server->ops->check_trans2 &&
697 server->ops->check_trans2(mid, server, buf, malformed))
698 return;
699 mid->credits_received = smb2_get_credits_from_hdr(buf, server);
700 mid->resp_buf = buf;
701 mid->large_buf = server->large_buf;
702 /* Was previous buf put in mpx struct for multi-rsp? */
703 if (!mid->multiRsp) {
704 /* smb buffer will be freed by user thread */
705 if (server->large_buf)
706 server->bigbuf = NULL;
707 else
708 server->smallbuf = NULL;
709 }
710 dequeue_mid(mid, malformed);
711}
712
713static void clean_demultiplex_info(struct TCP_Server_Info *server)
714{
715 int length;
716
717 /* take it off the list, if it's not already */
718 spin_lock(&cifs_tcp_ses_lock);
719 list_del_init(&server->tcp_ses_list);
720 spin_unlock(&cifs_tcp_ses_lock);
721
722 cancel_delayed_work_sync(&server->echo);
723 cancel_delayed_work_sync(&server->resolve);
724
725 spin_lock(&GlobalMid_Lock);
726 server->tcpStatus = CifsExiting;
727 spin_unlock(&GlobalMid_Lock);
728 wake_up_all(&server->response_q);
729
730 /* check if we have blocked requests that need to free */
731 spin_lock(&server->req_lock);
732 if (server->credits <= 0)
733 server->credits = 1;
734 spin_unlock(&server->req_lock);
735 /*
736 * Although there should not be any requests blocked on this queue it
737 * can not hurt to be paranoid and try to wake up requests that may
738 * haven been blocked when more than 50 at time were on the wire to the
739 * same server - they now will see the session is in exit state and get
740 * out of SendReceive.
741 */
742 wake_up_all(&server->request_q);
743 /* give those requests time to exit */
744 msleep(125);
745 if (cifs_rdma_enabled(server))
746 smbd_destroy(server);
747 if (server->ssocket) {
748 sock_release(server->ssocket);
749 server->ssocket = NULL;
750 }
751
752 if (!list_empty(&server->pending_mid_q)) {
753 struct list_head dispose_list;
754 struct mid_q_entry *mid_entry;
755 struct list_head *tmp, *tmp2;
756
757 INIT_LIST_HEAD(&dispose_list);
758 spin_lock(&GlobalMid_Lock);
759 list_for_each_safe(tmp, tmp2, &server->pending_mid_q) {
760 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
761 cifs_dbg(FYI, "Clearing mid %llu\n", mid_entry->mid);
762 kref_get(&mid_entry->refcount);
763 mid_entry->mid_state = MID_SHUTDOWN;
764 list_move(&mid_entry->qhead, &dispose_list);
765 mid_entry->mid_flags |= MID_DELETED;
766 }
767 spin_unlock(&GlobalMid_Lock);
768
769 /* now walk dispose list and issue callbacks */
770 list_for_each_safe(tmp, tmp2, &dispose_list) {
771 mid_entry = list_entry(tmp, struct mid_q_entry, qhead);
772 cifs_dbg(FYI, "Callback mid %llu\n", mid_entry->mid);
773 list_del_init(&mid_entry->qhead);
774 mid_entry->callback(mid_entry);
775 cifs_mid_q_entry_release(mid_entry);
776 }
777 /* 1/8th of sec is more than enough time for them to exit */
778 msleep(125);
779 }
780
781 if (!list_empty(&server->pending_mid_q)) {
782 /*
783 * mpx threads have not exited yet give them at least the smb
784 * send timeout time for long ops.
785 *
786 * Due to delays on oplock break requests, we need to wait at
787 * least 45 seconds before giving up on a request getting a
788 * response and going ahead and killing cifsd.
789 */
790 cifs_dbg(FYI, "Wait for exit from demultiplex thread\n");
791 msleep(46000);
792 /*
793 * If threads still have not exited they are probably never
794 * coming home not much else we can do but free the memory.
795 */
796 }
797
798 kfree(server->hostname);
799 kfree(server);
800
801 length = atomic_dec_return(&tcpSesAllocCount);
802 if (length > 0)
803 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
804}
805
806static int
807standard_receive3(struct TCP_Server_Info *server, struct mid_q_entry *mid)
808{
809 int length;
810 char *buf = server->smallbuf;
811 unsigned int pdu_length = server->pdu_size;
812
813 /* make sure this will fit in a large buffer */
814 if (pdu_length > CIFSMaxBufSize + MAX_HEADER_SIZE(server) -
815 server->vals->header_preamble_size) {
816 cifs_server_dbg(VFS, "SMB response too long (%u bytes)\n", pdu_length);
817 cifs_reconnect(server);
818 return -ECONNABORTED;
819 }
820
821 /* switch to large buffer if too big for a small one */
822 if (pdu_length > MAX_CIFS_SMALL_BUFFER_SIZE - 4) {
823 server->large_buf = true;
824 memcpy(server->bigbuf, buf, server->total_read);
825 buf = server->bigbuf;
826 }
827
828 /* now read the rest */
829 length = cifs_read_from_socket(server, buf + HEADER_SIZE(server) - 1,
830 pdu_length - HEADER_SIZE(server) + 1
831 + server->vals->header_preamble_size);
832
833 if (length < 0)
834 return length;
835 server->total_read += length;
836
837 dump_smb(buf, server->total_read);
838
839 return cifs_handle_standard(server, mid);
840}
841
842int
843cifs_handle_standard(struct TCP_Server_Info *server, struct mid_q_entry *mid)
844{
845 char *buf = server->large_buf ? server->bigbuf : server->smallbuf;
846 int length;
847
848 /*
849 * We know that we received enough to get to the MID as we
850 * checked the pdu_length earlier. Now check to see
851 * if the rest of the header is OK. We borrow the length
852 * var for the rest of the loop to avoid a new stack var.
853 *
854 * 48 bytes is enough to display the header and a little bit
855 * into the payload for debugging purposes.
856 */
857 length = server->ops->check_message(buf, server->total_read, server);
858 if (length != 0)
859 cifs_dump_mem("Bad SMB: ", buf,
860 min_t(unsigned int, server->total_read, 48));
861
862 if (server->ops->is_session_expired &&
863 server->ops->is_session_expired(buf)) {
864 cifs_reconnect(server);
865 return -1;
866 }
867
868 if (server->ops->is_status_pending &&
869 server->ops->is_status_pending(buf, server))
870 return -1;
871
872 if (!mid)
873 return length;
874
875 handle_mid(mid, server, buf, length);
876 return 0;
877}
878
879static void
880smb2_add_credits_from_hdr(char *buffer, struct TCP_Server_Info *server)
881{
882 struct smb2_sync_hdr *shdr = (struct smb2_sync_hdr *)buffer;
883 int scredits, in_flight;
884
885 /*
886 * SMB1 does not use credits.
887 */
888 if (server->vals->header_preamble_size)
889 return;
890
891 if (shdr->CreditRequest) {
892 spin_lock(&server->req_lock);
893 server->credits += le16_to_cpu(shdr->CreditRequest);
894 scredits = server->credits;
895 in_flight = server->in_flight;
896 spin_unlock(&server->req_lock);
897 wake_up(&server->request_q);
898
899 trace_smb3_add_credits(server->CurrentMid,
900 server->conn_id, server->hostname, scredits,
901 le16_to_cpu(shdr->CreditRequest), in_flight);
902 cifs_server_dbg(FYI, "%s: added %u credits total=%d\n",
903 __func__, le16_to_cpu(shdr->CreditRequest),
904 scredits);
905 }
906}
907
908
909static int
910cifs_demultiplex_thread(void *p)
911{
912 int i, num_mids, length;
913 struct TCP_Server_Info *server = p;
914 unsigned int pdu_length;
915 unsigned int next_offset;
916 char *buf = NULL;
917 struct task_struct *task_to_wake = NULL;
918 struct mid_q_entry *mids[MAX_COMPOUND];
919 char *bufs[MAX_COMPOUND];
920 unsigned int noreclaim_flag, num_io_timeout = 0;
921
922 noreclaim_flag = memalloc_noreclaim_save();
923 cifs_dbg(FYI, "Demultiplex PID: %d\n", task_pid_nr(current));
924
925 length = atomic_inc_return(&tcpSesAllocCount);
926 if (length > 1)
927 mempool_resize(cifs_req_poolp, length + cifs_min_rcv);
928
929 set_freezable();
930 allow_kernel_signal(SIGKILL);
931 while (server->tcpStatus != CifsExiting) {
932 if (try_to_freeze())
933 continue;
934
935 if (!allocate_buffers(server))
936 continue;
937
938 server->large_buf = false;
939 buf = server->smallbuf;
940 pdu_length = 4; /* enough to get RFC1001 header */
941
942 length = cifs_read_from_socket(server, buf, pdu_length);
943 if (length < 0)
944 continue;
945
946 if (server->vals->header_preamble_size == 0)
947 server->total_read = 0;
948 else
949 server->total_read = length;
950
951 /*
952 * The right amount was read from socket - 4 bytes,
953 * so we can now interpret the length field.
954 */
955 pdu_length = get_rfc1002_length(buf);
956
957 cifs_dbg(FYI, "RFC1002 header 0x%x\n", pdu_length);
958 if (!is_smb_response(server, buf[0]))
959 continue;
960next_pdu:
961 server->pdu_size = pdu_length;
962
963 /* make sure we have enough to get to the MID */
964 if (server->pdu_size < HEADER_SIZE(server) - 1 -
965 server->vals->header_preamble_size) {
966 cifs_server_dbg(VFS, "SMB response too short (%u bytes)\n",
967 server->pdu_size);
968 cifs_reconnect(server);
969 continue;
970 }
971
972 /* read down to the MID */
973 length = cifs_read_from_socket(server,
974 buf + server->vals->header_preamble_size,
975 HEADER_SIZE(server) - 1
976 - server->vals->header_preamble_size);
977 if (length < 0)
978 continue;
979 server->total_read += length;
980
981 if (server->ops->next_header) {
982 next_offset = server->ops->next_header(buf);
983 if (next_offset)
984 server->pdu_size = next_offset;
985 }
986
987 memset(mids, 0, sizeof(mids));
988 memset(bufs, 0, sizeof(bufs));
989 num_mids = 0;
990
991 if (server->ops->is_transform_hdr &&
992 server->ops->receive_transform &&
993 server->ops->is_transform_hdr(buf)) {
994 length = server->ops->receive_transform(server,
995 mids,
996 bufs,
997 &num_mids);
998 } else {
999 mids[0] = server->ops->find_mid(server, buf);
1000 bufs[0] = buf;
1001 num_mids = 1;
1002
1003 if (!mids[0] || !mids[0]->receive)
1004 length = standard_receive3(server, mids[0]);
1005 else
1006 length = mids[0]->receive(server, mids[0]);
1007 }
1008
1009 if (length < 0) {
1010 for (i = 0; i < num_mids; i++)
1011 if (mids[i])
1012 cifs_mid_q_entry_release(mids[i]);
1013 continue;
1014 }
1015
1016 if (server->ops->is_status_io_timeout &&
1017 server->ops->is_status_io_timeout(buf)) {
1018 num_io_timeout++;
1019 if (num_io_timeout > NUM_STATUS_IO_TIMEOUT) {
1020 cifs_reconnect(server);
1021 num_io_timeout = 0;
1022 continue;
1023 }
1024 }
1025
1026 server->lstrp = jiffies;
1027
1028 for (i = 0; i < num_mids; i++) {
1029 if (mids[i] != NULL) {
1030 mids[i]->resp_buf_size = server->pdu_size;
1031
1032 if (bufs[i] && server->ops->is_network_name_deleted)
1033 server->ops->is_network_name_deleted(bufs[i],
1034 server);
1035
1036 if (!mids[i]->multiRsp || mids[i]->multiEnd)
1037 mids[i]->callback(mids[i]);
1038
1039 cifs_mid_q_entry_release(mids[i]);
1040 } else if (server->ops->is_oplock_break &&
1041 server->ops->is_oplock_break(bufs[i],
1042 server)) {
1043 smb2_add_credits_from_hdr(bufs[i], server);
1044 cifs_dbg(FYI, "Received oplock break\n");
1045 } else {
1046 cifs_server_dbg(VFS, "No task to wake, unknown frame received! NumMids %d\n",
1047 atomic_read(&midCount));
1048 cifs_dump_mem("Received Data is: ", bufs[i],
1049 HEADER_SIZE(server));
1050 smb2_add_credits_from_hdr(bufs[i], server);
1051#ifdef CONFIG_CIFS_DEBUG2
1052 if (server->ops->dump_detail)
1053 server->ops->dump_detail(bufs[i],
1054 server);
1055 cifs_dump_mids(server);
1056#endif /* CIFS_DEBUG2 */
1057 }
1058 }
1059
1060 if (pdu_length > server->pdu_size) {
1061 if (!allocate_buffers(server))
1062 continue;
1063 pdu_length -= server->pdu_size;
1064 server->total_read = 0;
1065 server->large_buf = false;
1066 buf = server->smallbuf;
1067 goto next_pdu;
1068 }
1069 } /* end while !EXITING */
1070
1071 /* buffer usually freed in free_mid - need to free it here on exit */
1072 cifs_buf_release(server->bigbuf);
1073 if (server->smallbuf) /* no sense logging a debug message if NULL */
1074 cifs_small_buf_release(server->smallbuf);
1075
1076 task_to_wake = xchg(&server->tsk, NULL);
1077 clean_demultiplex_info(server);
1078
1079 /* if server->tsk was NULL then wait for a signal before exiting */
1080 if (!task_to_wake) {
1081 set_current_state(TASK_INTERRUPTIBLE);
1082 while (!signal_pending(current)) {
1083 schedule();
1084 set_current_state(TASK_INTERRUPTIBLE);
1085 }
1086 set_current_state(TASK_RUNNING);
1087 }
1088
1089 memalloc_noreclaim_restore(noreclaim_flag);
1090 module_put_and_exit(0);
1091}
1092
1093/**
1094 * Returns true if srcaddr isn't specified and rhs isn't specified, or
1095 * if srcaddr is specified and matches the IP address of the rhs argument
1096 */
1097bool
1098cifs_match_ipaddr(struct sockaddr *srcaddr, struct sockaddr *rhs)
1099{
1100 switch (srcaddr->sa_family) {
1101 case AF_UNSPEC:
1102 return (rhs->sa_family == AF_UNSPEC);
1103 case AF_INET: {
1104 struct sockaddr_in *saddr4 = (struct sockaddr_in *)srcaddr;
1105 struct sockaddr_in *vaddr4 = (struct sockaddr_in *)rhs;
1106 return (saddr4->sin_addr.s_addr == vaddr4->sin_addr.s_addr);
1107 }
1108 case AF_INET6: {
1109 struct sockaddr_in6 *saddr6 = (struct sockaddr_in6 *)srcaddr;
1110 struct sockaddr_in6 *vaddr6 = (struct sockaddr_in6 *)rhs;
1111 return ipv6_addr_equal(&saddr6->sin6_addr, &vaddr6->sin6_addr);
1112 }
1113 default:
1114 WARN_ON(1);
1115 return false; /* don't expect to be here */
1116 }
1117}
1118
1119/*
1120 * If no port is specified in addr structure, we try to match with 445 port
1121 * and if it fails - with 139 ports. It should be called only if address
1122 * families of server and addr are equal.
1123 */
1124static bool
1125match_port(struct TCP_Server_Info *server, struct sockaddr *addr)
1126{
1127 __be16 port, *sport;
1128
1129 /* SMBDirect manages its own ports, don't match it here */
1130 if (server->rdma)
1131 return true;
1132
1133 switch (addr->sa_family) {
1134 case AF_INET:
1135 sport = &((struct sockaddr_in *) &server->dstaddr)->sin_port;
1136 port = ((struct sockaddr_in *) addr)->sin_port;
1137 break;
1138 case AF_INET6:
1139 sport = &((struct sockaddr_in6 *) &server->dstaddr)->sin6_port;
1140 port = ((struct sockaddr_in6 *) addr)->sin6_port;
1141 break;
1142 default:
1143 WARN_ON(1);
1144 return false;
1145 }
1146
1147 if (!port) {
1148 port = htons(CIFS_PORT);
1149 if (port == *sport)
1150 return true;
1151
1152 port = htons(RFC1001_PORT);
1153 }
1154
1155 return port == *sport;
1156}
1157
1158static bool
1159match_address(struct TCP_Server_Info *server, struct sockaddr *addr,
1160 struct sockaddr *srcaddr)
1161{
1162 switch (addr->sa_family) {
1163 case AF_INET: {
1164 struct sockaddr_in *addr4 = (struct sockaddr_in *)addr;
1165 struct sockaddr_in *srv_addr4 =
1166 (struct sockaddr_in *)&server->dstaddr;
1167
1168 if (addr4->sin_addr.s_addr != srv_addr4->sin_addr.s_addr)
1169 return false;
1170 break;
1171 }
1172 case AF_INET6: {
1173 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)addr;
1174 struct sockaddr_in6 *srv_addr6 =
1175 (struct sockaddr_in6 *)&server->dstaddr;
1176
1177 if (!ipv6_addr_equal(&addr6->sin6_addr,
1178 &srv_addr6->sin6_addr))
1179 return false;
1180 if (addr6->sin6_scope_id != srv_addr6->sin6_scope_id)
1181 return false;
1182 break;
1183 }
1184 default:
1185 WARN_ON(1);
1186 return false; /* don't expect to be here */
1187 }
1188
1189 if (!cifs_match_ipaddr(srcaddr, (struct sockaddr *)&server->srcaddr))
1190 return false;
1191
1192 return true;
1193}
1194
1195static bool
1196match_security(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1197{
1198 /*
1199 * The select_sectype function should either return the ctx->sectype
1200 * that was specified, or "Unspecified" if that sectype was not
1201 * compatible with the given NEGOTIATE request.
1202 */
1203 if (server->ops->select_sectype(server, ctx->sectype)
1204 == Unspecified)
1205 return false;
1206
1207 /*
1208 * Now check if signing mode is acceptable. No need to check
1209 * global_secflags at this point since if MUST_SIGN is set then
1210 * the server->sign had better be too.
1211 */
1212 if (ctx->sign && !server->sign)
1213 return false;
1214
1215 return true;
1216}
1217
1218static int match_server(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1219{
1220 struct sockaddr *addr = (struct sockaddr *)&ctx->dstaddr;
1221
1222 if (ctx->nosharesock)
1223 return 0;
1224
1225 /* If multidialect negotiation see if existing sessions match one */
1226 if (strcmp(ctx->vals->version_string, SMB3ANY_VERSION_STRING) == 0) {
1227 if (server->vals->protocol_id < SMB30_PROT_ID)
1228 return 0;
1229 } else if (strcmp(ctx->vals->version_string,
1230 SMBDEFAULT_VERSION_STRING) == 0) {
1231 if (server->vals->protocol_id < SMB21_PROT_ID)
1232 return 0;
1233 } else if ((server->vals != ctx->vals) || (server->ops != ctx->ops))
1234 return 0;
1235
1236 if (!net_eq(cifs_net_ns(server), current->nsproxy->net_ns))
1237 return 0;
1238
1239 if (!match_address(server, addr,
1240 (struct sockaddr *)&ctx->srcaddr))
1241 return 0;
1242
1243 if (!match_port(server, addr))
1244 return 0;
1245
1246 if (!match_security(server, ctx))
1247 return 0;
1248
1249 if (server->echo_interval != ctx->echo_interval * HZ)
1250 return 0;
1251
1252 if (server->rdma != ctx->rdma)
1253 return 0;
1254
1255 if (server->ignore_signature != ctx->ignore_signature)
1256 return 0;
1257
1258 if (server->min_offload != ctx->min_offload)
1259 return 0;
1260
1261 return 1;
1262}
1263
1264struct TCP_Server_Info *
1265cifs_find_tcp_session(struct smb3_fs_context *ctx)
1266{
1267 struct TCP_Server_Info *server;
1268
1269 spin_lock(&cifs_tcp_ses_lock);
1270 list_for_each_entry(server, &cifs_tcp_ses_list, tcp_ses_list) {
1271#ifdef CONFIG_CIFS_DFS_UPCALL
1272 /*
1273 * DFS failover implementation in cifs_reconnect() requires unique tcp sessions for
1274 * DFS connections to do failover properly, so avoid sharing them with regular
1275 * shares or even links that may connect to same server but having completely
1276 * different failover targets.
1277 */
1278 if (server->is_dfs_conn)
1279 continue;
1280#endif
1281 /*
1282 * Skip ses channels since they're only handled in lower layers
1283 * (e.g. cifs_send_recv).
1284 */
1285 if (server->is_channel || !match_server(server, ctx))
1286 continue;
1287
1288 ++server->srv_count;
1289 spin_unlock(&cifs_tcp_ses_lock);
1290 cifs_dbg(FYI, "Existing tcp session with server found\n");
1291 return server;
1292 }
1293 spin_unlock(&cifs_tcp_ses_lock);
1294 return NULL;
1295}
1296
1297void
1298cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
1299{
1300 struct task_struct *task;
1301
1302 spin_lock(&cifs_tcp_ses_lock);
1303 if (--server->srv_count > 0) {
1304 spin_unlock(&cifs_tcp_ses_lock);
1305 return;
1306 }
1307
1308 /* srv_count can never go negative */
1309 WARN_ON(server->srv_count < 0);
1310
1311 put_net(cifs_net_ns(server));
1312
1313 list_del_init(&server->tcp_ses_list);
1314 spin_unlock(&cifs_tcp_ses_lock);
1315
1316 cancel_delayed_work_sync(&server->echo);
1317 cancel_delayed_work_sync(&server->resolve);
1318
1319 if (from_reconnect)
1320 /*
1321 * Avoid deadlock here: reconnect work calls
1322 * cifs_put_tcp_session() at its end. Need to be sure
1323 * that reconnect work does nothing with server pointer after
1324 * that step.
1325 */
1326 cancel_delayed_work(&server->reconnect);
1327 else
1328 cancel_delayed_work_sync(&server->reconnect);
1329
1330 spin_lock(&GlobalMid_Lock);
1331 server->tcpStatus = CifsExiting;
1332 spin_unlock(&GlobalMid_Lock);
1333
1334 cifs_crypto_secmech_release(server);
1335 cifs_fscache_release_client_cookie(server);
1336
1337 kfree(server->session_key.response);
1338 server->session_key.response = NULL;
1339 server->session_key.len = 0;
1340
1341 task = xchg(&server->tsk, NULL);
1342 if (task)
1343 send_sig(SIGKILL, task, 1);
1344}
1345
1346struct TCP_Server_Info *
1347cifs_get_tcp_session(struct smb3_fs_context *ctx)
1348{
1349 struct TCP_Server_Info *tcp_ses = NULL;
1350 int rc;
1351
1352 cifs_dbg(FYI, "UNC: %s\n", ctx->UNC);
1353
1354 /* see if we already have a matching tcp_ses */
1355 tcp_ses = cifs_find_tcp_session(ctx);
1356 if (tcp_ses)
1357 return tcp_ses;
1358
1359 tcp_ses = kzalloc(sizeof(struct TCP_Server_Info), GFP_KERNEL);
1360 if (!tcp_ses) {
1361 rc = -ENOMEM;
1362 goto out_err;
1363 }
1364
1365 tcp_ses->ops = ctx->ops;
1366 tcp_ses->vals = ctx->vals;
1367 cifs_set_net_ns(tcp_ses, get_net(current->nsproxy->net_ns));
1368 tcp_ses->hostname = extract_hostname(ctx->UNC);
1369 if (IS_ERR(tcp_ses->hostname)) {
1370 rc = PTR_ERR(tcp_ses->hostname);
1371 goto out_err_crypto_release;
1372 }
1373
1374 tcp_ses->conn_id = atomic_inc_return(&tcpSesNextId);
1375 tcp_ses->noblockcnt = ctx->rootfs;
1376 tcp_ses->noblocksnd = ctx->noblocksnd || ctx->rootfs;
1377 tcp_ses->noautotune = ctx->noautotune;
1378 tcp_ses->tcp_nodelay = ctx->sockopt_tcp_nodelay;
1379 tcp_ses->rdma = ctx->rdma;
1380 tcp_ses->in_flight = 0;
1381 tcp_ses->max_in_flight = 0;
1382 tcp_ses->credits = 1;
1383 init_waitqueue_head(&tcp_ses->response_q);
1384 init_waitqueue_head(&tcp_ses->request_q);
1385 INIT_LIST_HEAD(&tcp_ses->pending_mid_q);
1386 mutex_init(&tcp_ses->srv_mutex);
1387 memcpy(tcp_ses->workstation_RFC1001_name,
1388 ctx->source_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1389 memcpy(tcp_ses->server_RFC1001_name,
1390 ctx->target_rfc1001_name, RFC1001_NAME_LEN_WITH_NULL);
1391 tcp_ses->session_estab = false;
1392 tcp_ses->sequence_number = 0;
1393 tcp_ses->reconnect_instance = 1;
1394 tcp_ses->lstrp = jiffies;
1395 tcp_ses->compress_algorithm = cpu_to_le16(ctx->compression);
1396 spin_lock_init(&tcp_ses->req_lock);
1397 INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
1398 INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
1399 INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
1400 INIT_DELAYED_WORK(&tcp_ses->resolve, cifs_resolve_server);
1401 INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
1402 mutex_init(&tcp_ses->reconnect_mutex);
1403 memcpy(&tcp_ses->srcaddr, &ctx->srcaddr,
1404 sizeof(tcp_ses->srcaddr));
1405 memcpy(&tcp_ses->dstaddr, &ctx->dstaddr,
1406 sizeof(tcp_ses->dstaddr));
1407 if (ctx->use_client_guid)
1408 memcpy(tcp_ses->client_guid, ctx->client_guid,
1409 SMB2_CLIENT_GUID_SIZE);
1410 else
1411 generate_random_uuid(tcp_ses->client_guid);
1412 /*
1413 * at this point we are the only ones with the pointer
1414 * to the struct since the kernel thread not created yet
1415 * no need to spinlock this init of tcpStatus or srv_count
1416 */
1417 tcp_ses->tcpStatus = CifsNew;
1418 ++tcp_ses->srv_count;
1419
1420 if (ctx->echo_interval >= SMB_ECHO_INTERVAL_MIN &&
1421 ctx->echo_interval <= SMB_ECHO_INTERVAL_MAX)
1422 tcp_ses->echo_interval = ctx->echo_interval * HZ;
1423 else
1424 tcp_ses->echo_interval = SMB_ECHO_INTERVAL_DEFAULT * HZ;
1425 if (tcp_ses->rdma) {
1426#ifndef CONFIG_CIFS_SMB_DIRECT
1427 cifs_dbg(VFS, "CONFIG_CIFS_SMB_DIRECT is not enabled\n");
1428 rc = -ENOENT;
1429 goto out_err_crypto_release;
1430#endif
1431 tcp_ses->smbd_conn = smbd_get_connection(
1432 tcp_ses, (struct sockaddr *)&ctx->dstaddr);
1433 if (tcp_ses->smbd_conn) {
1434 cifs_dbg(VFS, "RDMA transport established\n");
1435 rc = 0;
1436 goto smbd_connected;
1437 } else {
1438 rc = -ENOENT;
1439 goto out_err_crypto_release;
1440 }
1441 }
1442 rc = ip_connect(tcp_ses);
1443 if (rc < 0) {
1444 cifs_dbg(VFS, "Error connecting to socket. Aborting operation.\n");
1445 goto out_err_crypto_release;
1446 }
1447smbd_connected:
1448 /*
1449 * since we're in a cifs function already, we know that
1450 * this will succeed. No need for try_module_get().
1451 */
1452 __module_get(THIS_MODULE);
1453 tcp_ses->tsk = kthread_run(cifs_demultiplex_thread,
1454 tcp_ses, "cifsd");
1455 if (IS_ERR(tcp_ses->tsk)) {
1456 rc = PTR_ERR(tcp_ses->tsk);
1457 cifs_dbg(VFS, "error %d create cifsd thread\n", rc);
1458 module_put(THIS_MODULE);
1459 goto out_err_crypto_release;
1460 }
1461 tcp_ses->min_offload = ctx->min_offload;
1462 /*
1463 * at this point we are the only ones with the pointer
1464 * to the struct since the kernel thread not created yet
1465 * no need to spinlock this update of tcpStatus
1466 */
1467 tcp_ses->tcpStatus = CifsNeedNegotiate;
1468
1469 if ((ctx->max_credits < 20) || (ctx->max_credits > 60000))
1470 tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE;
1471 else
1472 tcp_ses->max_credits = ctx->max_credits;
1473
1474 tcp_ses->nr_targets = 1;
1475 tcp_ses->ignore_signature = ctx->ignore_signature;
1476 /* thread spawned, put it on the list */
1477 spin_lock(&cifs_tcp_ses_lock);
1478 list_add(&tcp_ses->tcp_ses_list, &cifs_tcp_ses_list);
1479 spin_unlock(&cifs_tcp_ses_lock);
1480
1481 cifs_fscache_get_client_cookie(tcp_ses);
1482
1483 /* queue echo request delayed work */
1484 queue_delayed_work(cifsiod_wq, &tcp_ses->echo, tcp_ses->echo_interval);
1485
1486 /* queue dns resolution delayed work */
1487 cifs_dbg(FYI, "%s: next dns resolution scheduled for %d seconds in the future\n",
1488 __func__, SMB_DNS_RESOLVE_INTERVAL_DEFAULT);
1489
1490 queue_delayed_work(cifsiod_wq, &tcp_ses->resolve, (SMB_DNS_RESOLVE_INTERVAL_DEFAULT * HZ));
1491
1492 return tcp_ses;
1493
1494out_err_crypto_release:
1495 cifs_crypto_secmech_release(tcp_ses);
1496
1497 put_net(cifs_net_ns(tcp_ses));
1498
1499out_err:
1500 if (tcp_ses) {
1501 if (!IS_ERR(tcp_ses->hostname))
1502 kfree(tcp_ses->hostname);
1503 if (tcp_ses->ssocket)
1504 sock_release(tcp_ses->ssocket);
1505 kfree(tcp_ses);
1506 }
1507 return ERR_PTR(rc);
1508}
1509
1510static int match_session(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1511{
1512 if (ctx->sectype != Unspecified &&
1513 ctx->sectype != ses->sectype)
1514 return 0;
1515
1516 /*
1517 * If an existing session is limited to less channels than
1518 * requested, it should not be reused
1519 */
1520 if (ses->chan_max < ctx->max_channels)
1521 return 0;
1522
1523 switch (ses->sectype) {
1524 case Kerberos:
1525 if (!uid_eq(ctx->cred_uid, ses->cred_uid))
1526 return 0;
1527 break;
1528 default:
1529 /* NULL username means anonymous session */
1530 if (ses->user_name == NULL) {
1531 if (!ctx->nullauth)
1532 return 0;
1533 break;
1534 }
1535
1536 /* anything else takes username/password */
1537 if (strncmp(ses->user_name,
1538 ctx->username ? ctx->username : "",
1539 CIFS_MAX_USERNAME_LEN))
1540 return 0;
1541 if ((ctx->username && strlen(ctx->username) != 0) &&
1542 ses->password != NULL &&
1543 strncmp(ses->password,
1544 ctx->password ? ctx->password : "",
1545 CIFS_MAX_PASSWORD_LEN))
1546 return 0;
1547 }
1548 return 1;
1549}
1550
1551/**
1552 * cifs_setup_ipc - helper to setup the IPC tcon for the session
1553 *
1554 * A new IPC connection is made and stored in the session
1555 * tcon_ipc. The IPC tcon has the same lifetime as the session.
1556 */
1557static int
1558cifs_setup_ipc(struct cifs_ses *ses, struct smb3_fs_context *ctx)
1559{
1560 int rc = 0, xid;
1561 struct cifs_tcon *tcon;
1562 char unc[SERVER_NAME_LENGTH + sizeof("//x/IPC$")] = {0};
1563 bool seal = false;
1564 struct TCP_Server_Info *server = ses->server;
1565
1566 /*
1567 * If the mount request that resulted in the creation of the
1568 * session requires encryption, force IPC to be encrypted too.
1569 */
1570 if (ctx->seal) {
1571 if (server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION)
1572 seal = true;
1573 else {
1574 cifs_server_dbg(VFS,
1575 "IPC: server doesn't support encryption\n");
1576 return -EOPNOTSUPP;
1577 }
1578 }
1579
1580 tcon = tconInfoAlloc();
1581 if (tcon == NULL)
1582 return -ENOMEM;
1583
1584 scnprintf(unc, sizeof(unc), "\\\\%s\\IPC$", server->hostname);
1585
1586 xid = get_xid();
1587 tcon->ses = ses;
1588 tcon->ipc = true;
1589 tcon->seal = seal;
1590 rc = server->ops->tree_connect(xid, ses, unc, tcon, ctx->local_nls);
1591 free_xid(xid);
1592
1593 if (rc) {
1594 cifs_server_dbg(VFS, "failed to connect to IPC (rc=%d)\n", rc);
1595 tconInfoFree(tcon);
1596 goto out;
1597 }
1598
1599 cifs_dbg(FYI, "IPC tcon rc = %d ipc tid = %d\n", rc, tcon->tid);
1600
1601 ses->tcon_ipc = tcon;
1602out:
1603 return rc;
1604}
1605
1606/**
1607 * cifs_free_ipc - helper to release the session IPC tcon
1608 *
1609 * Needs to be called everytime a session is destroyed.
1610 *
1611 * On session close, the IPC is closed and the server must release all tcons of the session.
1612 * No need to send a tree disconnect here.
1613 *
1614 * Besides, it will make the server to not close durable and resilient files on session close, as
1615 * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
1616 */
1617static int
1618cifs_free_ipc(struct cifs_ses *ses)
1619{
1620 struct cifs_tcon *tcon = ses->tcon_ipc;
1621
1622 if (tcon == NULL)
1623 return 0;
1624
1625 tconInfoFree(tcon);
1626 ses->tcon_ipc = NULL;
1627 return 0;
1628}
1629
1630static struct cifs_ses *
1631cifs_find_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1632{
1633 struct cifs_ses *ses;
1634
1635 spin_lock(&cifs_tcp_ses_lock);
1636 list_for_each_entry(ses, &server->smb_ses_list, smb_ses_list) {
1637 if (ses->status == CifsExiting)
1638 continue;
1639 if (!match_session(ses, ctx))
1640 continue;
1641 ++ses->ses_count;
1642 spin_unlock(&cifs_tcp_ses_lock);
1643 return ses;
1644 }
1645 spin_unlock(&cifs_tcp_ses_lock);
1646 return NULL;
1647}
1648
1649void cifs_put_smb_ses(struct cifs_ses *ses)
1650{
1651 unsigned int rc, xid;
1652 struct TCP_Server_Info *server = ses->server;
1653 cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
1654
1655 spin_lock(&cifs_tcp_ses_lock);
1656 if (ses->status == CifsExiting) {
1657 spin_unlock(&cifs_tcp_ses_lock);
1658 return;
1659 }
1660
1661 cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
1662 cifs_dbg(FYI, "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->treeName : "NONE");
1663
1664 if (--ses->ses_count > 0) {
1665 spin_unlock(&cifs_tcp_ses_lock);
1666 return;
1667 }
1668 spin_unlock(&cifs_tcp_ses_lock);
1669
1670 /* ses_count can never go negative */
1671 WARN_ON(ses->ses_count < 0);
1672
1673 spin_lock(&GlobalMid_Lock);
1674 if (ses->status == CifsGood)
1675 ses->status = CifsExiting;
1676 spin_unlock(&GlobalMid_Lock);
1677
1678 cifs_free_ipc(ses);
1679
1680 if (ses->status == CifsExiting && server->ops->logoff) {
1681 xid = get_xid();
1682 rc = server->ops->logoff(xid, ses);
1683 if (rc)
1684 cifs_server_dbg(VFS, "%s: Session Logoff failure rc=%d\n",
1685 __func__, rc);
1686 _free_xid(xid);
1687 }
1688
1689 spin_lock(&cifs_tcp_ses_lock);
1690 list_del_init(&ses->smb_ses_list);
1691 spin_unlock(&cifs_tcp_ses_lock);
1692
1693 /* close any extra channels */
1694 if (ses->chan_count > 1) {
1695 int i;
1696
1697 for (i = 1; i < ses->chan_count; i++)
1698 cifs_put_tcp_session(ses->chans[i].server, 0);
1699 }
1700
1701 sesInfoFree(ses);
1702 cifs_put_tcp_session(server, 0);
1703}
1704
1705#ifdef CONFIG_KEYS
1706
1707/* strlen("cifs:a:") + CIFS_MAX_DOMAINNAME_LEN + 1 */
1708#define CIFSCREDS_DESC_SIZE (7 + CIFS_MAX_DOMAINNAME_LEN + 1)
1709
1710/* Populate username and pw fields from keyring if possible */
1711static int
1712cifs_set_cifscreds(struct smb3_fs_context *ctx, struct cifs_ses *ses)
1713{
1714 int rc = 0;
1715 int is_domain = 0;
1716 const char *delim, *payload;
1717 char *desc;
1718 ssize_t len;
1719 struct key *key;
1720 struct TCP_Server_Info *server = ses->server;
1721 struct sockaddr_in *sa;
1722 struct sockaddr_in6 *sa6;
1723 const struct user_key_payload *upayload;
1724
1725 desc = kmalloc(CIFSCREDS_DESC_SIZE, GFP_KERNEL);
1726 if (!desc)
1727 return -ENOMEM;
1728
1729 /* try to find an address key first */
1730 switch (server->dstaddr.ss_family) {
1731 case AF_INET:
1732 sa = (struct sockaddr_in *)&server->dstaddr;
1733 sprintf(desc, "cifs:a:%pI4", &sa->sin_addr.s_addr);
1734 break;
1735 case AF_INET6:
1736 sa6 = (struct sockaddr_in6 *)&server->dstaddr;
1737 sprintf(desc, "cifs:a:%pI6c", &sa6->sin6_addr.s6_addr);
1738 break;
1739 default:
1740 cifs_dbg(FYI, "Bad ss_family (%hu)\n",
1741 server->dstaddr.ss_family);
1742 rc = -EINVAL;
1743 goto out_err;
1744 }
1745
1746 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
1747 key = request_key(&key_type_logon, desc, "");
1748 if (IS_ERR(key)) {
1749 if (!ses->domainName) {
1750 cifs_dbg(FYI, "domainName is NULL\n");
1751 rc = PTR_ERR(key);
1752 goto out_err;
1753 }
1754
1755 /* didn't work, try to find a domain key */
1756 sprintf(desc, "cifs:d:%s", ses->domainName);
1757 cifs_dbg(FYI, "%s: desc=%s\n", __func__, desc);
1758 key = request_key(&key_type_logon, desc, "");
1759 if (IS_ERR(key)) {
1760 rc = PTR_ERR(key);
1761 goto out_err;
1762 }
1763 is_domain = 1;
1764 }
1765
1766 down_read(&key->sem);
1767 upayload = user_key_payload_locked(key);
1768 if (IS_ERR_OR_NULL(upayload)) {
1769 rc = upayload ? PTR_ERR(upayload) : -EINVAL;
1770 goto out_key_put;
1771 }
1772
1773 /* find first : in payload */
1774 payload = upayload->data;
1775 delim = strnchr(payload, upayload->datalen, ':');
1776 cifs_dbg(FYI, "payload=%s\n", payload);
1777 if (!delim) {
1778 cifs_dbg(FYI, "Unable to find ':' in payload (datalen=%d)\n",
1779 upayload->datalen);
1780 rc = -EINVAL;
1781 goto out_key_put;
1782 }
1783
1784 len = delim - payload;
1785 if (len > CIFS_MAX_USERNAME_LEN || len <= 0) {
1786 cifs_dbg(FYI, "Bad value from username search (len=%zd)\n",
1787 len);
1788 rc = -EINVAL;
1789 goto out_key_put;
1790 }
1791
1792 ctx->username = kstrndup(payload, len, GFP_KERNEL);
1793 if (!ctx->username) {
1794 cifs_dbg(FYI, "Unable to allocate %zd bytes for username\n",
1795 len);
1796 rc = -ENOMEM;
1797 goto out_key_put;
1798 }
1799 cifs_dbg(FYI, "%s: username=%s\n", __func__, ctx->username);
1800
1801 len = key->datalen - (len + 1);
1802 if (len > CIFS_MAX_PASSWORD_LEN || len <= 0) {
1803 cifs_dbg(FYI, "Bad len for password search (len=%zd)\n", len);
1804 rc = -EINVAL;
1805 kfree(ctx->username);
1806 ctx->username = NULL;
1807 goto out_key_put;
1808 }
1809
1810 ++delim;
1811 ctx->password = kstrndup(delim, len, GFP_KERNEL);
1812 if (!ctx->password) {
1813 cifs_dbg(FYI, "Unable to allocate %zd bytes for password\n",
1814 len);
1815 rc = -ENOMEM;
1816 kfree(ctx->username);
1817 ctx->username = NULL;
1818 goto out_key_put;
1819 }
1820
1821 /*
1822 * If we have a domain key then we must set the domainName in the
1823 * for the request.
1824 */
1825 if (is_domain && ses->domainName) {
1826 ctx->domainname = kstrdup(ses->domainName, GFP_KERNEL);
1827 if (!ctx->domainname) {
1828 cifs_dbg(FYI, "Unable to allocate %zd bytes for domain\n",
1829 len);
1830 rc = -ENOMEM;
1831 kfree(ctx->username);
1832 ctx->username = NULL;
1833 kfree_sensitive(ctx->password);
1834 ctx->password = NULL;
1835 goto out_key_put;
1836 }
1837 }
1838
1839out_key_put:
1840 up_read(&key->sem);
1841 key_put(key);
1842out_err:
1843 kfree(desc);
1844 cifs_dbg(FYI, "%s: returning %d\n", __func__, rc);
1845 return rc;
1846}
1847#else /* ! CONFIG_KEYS */
1848static inline int
1849cifs_set_cifscreds(struct smb3_fs_context *ctx __attribute__((unused)),
1850 struct cifs_ses *ses __attribute__((unused)))
1851{
1852 return -ENOSYS;
1853}
1854#endif /* CONFIG_KEYS */
1855
1856/**
1857 * cifs_get_smb_ses - get a session matching @ctx data from @server
1858 *
1859 * This function assumes it is being called from cifs_mount() where we
1860 * already got a server reference (server refcount +1). See
1861 * cifs_get_tcon() for refcount explanations.
1862 */
1863struct cifs_ses *
1864cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb3_fs_context *ctx)
1865{
1866 int rc = -ENOMEM;
1867 unsigned int xid;
1868 struct cifs_ses *ses;
1869 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
1870 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
1871
1872 xid = get_xid();
1873
1874 ses = cifs_find_smb_ses(server, ctx);
1875 if (ses) {
1876 cifs_dbg(FYI, "Existing smb sess found (status=%d)\n",
1877 ses->status);
1878
1879 mutex_lock(&ses->session_mutex);
1880 rc = cifs_negotiate_protocol(xid, ses);
1881 if (rc) {
1882 mutex_unlock(&ses->session_mutex);
1883 /* problem -- put our ses reference */
1884 cifs_put_smb_ses(ses);
1885 free_xid(xid);
1886 return ERR_PTR(rc);
1887 }
1888 if (ses->need_reconnect) {
1889 cifs_dbg(FYI, "Session needs reconnect\n");
1890 rc = cifs_setup_session(xid, ses,
1891 ctx->local_nls);
1892 if (rc) {
1893 mutex_unlock(&ses->session_mutex);
1894 /* problem -- put our reference */
1895 cifs_put_smb_ses(ses);
1896 free_xid(xid);
1897 return ERR_PTR(rc);
1898 }
1899 }
1900 mutex_unlock(&ses->session_mutex);
1901
1902 /* existing SMB ses has a server reference already */
1903 cifs_put_tcp_session(server, 0);
1904 free_xid(xid);
1905 return ses;
1906 }
1907
1908 cifs_dbg(FYI, "Existing smb sess not found\n");
1909 ses = sesInfoAlloc();
1910 if (ses == NULL)
1911 goto get_ses_fail;
1912
1913 /* new SMB session uses our server ref */
1914 ses->server = server;
1915 if (server->dstaddr.ss_family == AF_INET6)
1916 sprintf(ses->ip_addr, "%pI6", &addr6->sin6_addr);
1917 else
1918 sprintf(ses->ip_addr, "%pI4", &addr->sin_addr);
1919
1920 if (ctx->username) {
1921 ses->user_name = kstrdup(ctx->username, GFP_KERNEL);
1922 if (!ses->user_name)
1923 goto get_ses_fail;
1924 }
1925
1926 /* ctx->password freed at unmount */
1927 if (ctx->password) {
1928 ses->password = kstrdup(ctx->password, GFP_KERNEL);
1929 if (!ses->password)
1930 goto get_ses_fail;
1931 }
1932 if (ctx->domainname) {
1933 ses->domainName = kstrdup(ctx->domainname, GFP_KERNEL);
1934 if (!ses->domainName)
1935 goto get_ses_fail;
1936 }
1937 if (ctx->domainauto)
1938 ses->domainAuto = ctx->domainauto;
1939 ses->cred_uid = ctx->cred_uid;
1940 ses->linux_uid = ctx->linux_uid;
1941
1942 ses->sectype = ctx->sectype;
1943 ses->sign = ctx->sign;
1944 mutex_lock(&ses->session_mutex);
1945
1946 /* add server as first channel */
1947 ses->chans[0].server = server;
1948 ses->chan_count = 1;
1949 ses->chan_max = ctx->multichannel ? ctx->max_channels:1;
1950
1951 rc = cifs_negotiate_protocol(xid, ses);
1952 if (!rc)
1953 rc = cifs_setup_session(xid, ses, ctx->local_nls);
1954
1955 /* each channel uses a different signing key */
1956 memcpy(ses->chans[0].signkey, ses->smb3signingkey,
1957 sizeof(ses->smb3signingkey));
1958
1959 mutex_unlock(&ses->session_mutex);
1960 if (rc)
1961 goto get_ses_fail;
1962
1963 /* success, put it on the list and add it as first channel */
1964 spin_lock(&cifs_tcp_ses_lock);
1965 list_add(&ses->smb_ses_list, &server->smb_ses_list);
1966 spin_unlock(&cifs_tcp_ses_lock);
1967
1968 free_xid(xid);
1969
1970 cifs_setup_ipc(ses, ctx);
1971
1972 return ses;
1973
1974get_ses_fail:
1975 sesInfoFree(ses);
1976 free_xid(xid);
1977 return ERR_PTR(rc);
1978}
1979
1980static int match_tcon(struct cifs_tcon *tcon, struct smb3_fs_context *ctx)
1981{
1982 if (tcon->tidStatus == CifsExiting)
1983 return 0;
1984 if (strncmp(tcon->treeName, ctx->UNC, MAX_TREE_SIZE))
1985 return 0;
1986 if (tcon->seal != ctx->seal)
1987 return 0;
1988 if (tcon->snapshot_time != ctx->snapshot_time)
1989 return 0;
1990 if (tcon->handle_timeout != ctx->handle_timeout)
1991 return 0;
1992 if (tcon->no_lease != ctx->no_lease)
1993 return 0;
1994 if (tcon->nodelete != ctx->nodelete)
1995 return 0;
1996 return 1;
1997}
1998
1999static struct cifs_tcon *
2000cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2001{
2002 struct list_head *tmp;
2003 struct cifs_tcon *tcon;
2004
2005 spin_lock(&cifs_tcp_ses_lock);
2006 list_for_each(tmp, &ses->tcon_list) {
2007 tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
2008
2009 if (!match_tcon(tcon, ctx))
2010 continue;
2011 ++tcon->tc_count;
2012 spin_unlock(&cifs_tcp_ses_lock);
2013 return tcon;
2014 }
2015 spin_unlock(&cifs_tcp_ses_lock);
2016 return NULL;
2017}
2018
2019void
2020cifs_put_tcon(struct cifs_tcon *tcon)
2021{
2022 unsigned int xid;
2023 struct cifs_ses *ses;
2024
2025 /*
2026 * IPC tcon share the lifetime of their session and are
2027 * destroyed in the session put function
2028 */
2029 if (tcon == NULL || tcon->ipc)
2030 return;
2031
2032 ses = tcon->ses;
2033 cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
2034 spin_lock(&cifs_tcp_ses_lock);
2035 if (--tcon->tc_count > 0) {
2036 spin_unlock(&cifs_tcp_ses_lock);
2037 return;
2038 }
2039
2040 /* tc_count can never go negative */
2041 WARN_ON(tcon->tc_count < 0);
2042
2043 if (tcon->use_witness) {
2044 int rc;
2045
2046 rc = cifs_swn_unregister(tcon);
2047 if (rc < 0) {
2048 cifs_dbg(VFS, "%s: Failed to unregister for witness notifications: %d\n",
2049 __func__, rc);
2050 }
2051 }
2052
2053 list_del_init(&tcon->tcon_list);
2054 spin_unlock(&cifs_tcp_ses_lock);
2055
2056 xid = get_xid();
2057 if (ses->server->ops->tree_disconnect)
2058 ses->server->ops->tree_disconnect(xid, tcon);
2059 _free_xid(xid);
2060
2061 cifs_fscache_release_super_cookie(tcon);
2062 tconInfoFree(tcon);
2063 cifs_put_smb_ses(ses);
2064}
2065
2066/**
2067 * cifs_get_tcon - get a tcon matching @ctx data from @ses
2068 *
2069 * - tcon refcount is the number of mount points using the tcon.
2070 * - ses refcount is the number of tcon using the session.
2071 *
2072 * 1. This function assumes it is being called from cifs_mount() where
2073 * we already got a session reference (ses refcount +1).
2074 *
2075 * 2. Since we're in the context of adding a mount point, the end
2076 * result should be either:
2077 *
2078 * a) a new tcon already allocated with refcount=1 (1 mount point) and
2079 * its session refcount incremented (1 new tcon). This +1 was
2080 * already done in (1).
2081 *
2082 * b) an existing tcon with refcount+1 (add a mount point to it) and
2083 * identical ses refcount (no new tcon). Because of (1) we need to
2084 * decrement the ses refcount.
2085 */
2086static struct cifs_tcon *
2087cifs_get_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
2088{
2089 int rc, xid;
2090 struct cifs_tcon *tcon;
2091
2092 tcon = cifs_find_tcon(ses, ctx);
2093 if (tcon) {
2094 /*
2095 * tcon has refcount already incremented but we need to
2096 * decrement extra ses reference gotten by caller (case b)
2097 */
2098 cifs_dbg(FYI, "Found match on UNC path\n");
2099 cifs_put_smb_ses(ses);
2100 return tcon;
2101 }
2102
2103 if (!ses->server->ops->tree_connect) {
2104 rc = -ENOSYS;
2105 goto out_fail;
2106 }
2107
2108 tcon = tconInfoAlloc();
2109 if (tcon == NULL) {
2110 rc = -ENOMEM;
2111 goto out_fail;
2112 }
2113
2114 if (ctx->snapshot_time) {
2115 if (ses->server->vals->protocol_id == 0) {
2116 cifs_dbg(VFS,
2117 "Use SMB2 or later for snapshot mount option\n");
2118 rc = -EOPNOTSUPP;
2119 goto out_fail;
2120 } else
2121 tcon->snapshot_time = ctx->snapshot_time;
2122 }
2123
2124 if (ctx->handle_timeout) {
2125 if (ses->server->vals->protocol_id == 0) {
2126 cifs_dbg(VFS,
2127 "Use SMB2.1 or later for handle timeout option\n");
2128 rc = -EOPNOTSUPP;
2129 goto out_fail;
2130 } else
2131 tcon->handle_timeout = ctx->handle_timeout;
2132 }
2133
2134 tcon->ses = ses;
2135 if (ctx->password) {
2136 tcon->password = kstrdup(ctx->password, GFP_KERNEL);
2137 if (!tcon->password) {
2138 rc = -ENOMEM;
2139 goto out_fail;
2140 }
2141 }
2142
2143 if (ctx->seal) {
2144 if (ses->server->vals->protocol_id == 0) {
2145 cifs_dbg(VFS,
2146 "SMB3 or later required for encryption\n");
2147 rc = -EOPNOTSUPP;
2148 goto out_fail;
2149 } else if (tcon->ses->server->capabilities &
2150 SMB2_GLOBAL_CAP_ENCRYPTION)
2151 tcon->seal = true;
2152 else {
2153 cifs_dbg(VFS, "Encryption is not supported on share\n");
2154 rc = -EOPNOTSUPP;
2155 goto out_fail;
2156 }
2157 }
2158
2159 if (ctx->linux_ext) {
2160 if (ses->server->posix_ext_supported) {
2161 tcon->posix_extensions = true;
2162 pr_warn_once("SMB3.11 POSIX Extensions are experimental\n");
2163 } else {
2164 cifs_dbg(VFS, "Server does not support mounting with posix SMB3.11 extensions\n");
2165 rc = -EOPNOTSUPP;
2166 goto out_fail;
2167 }
2168 }
2169
2170 /*
2171 * BB Do we need to wrap session_mutex around this TCon call and Unix
2172 * SetFS as we do on SessSetup and reconnect?
2173 */
2174 xid = get_xid();
2175 rc = ses->server->ops->tree_connect(xid, ses, ctx->UNC, tcon,
2176 ctx->local_nls);
2177 free_xid(xid);
2178 cifs_dbg(FYI, "Tcon rc = %d\n", rc);
2179 if (rc)
2180 goto out_fail;
2181
2182 tcon->use_persistent = false;
2183 /* check if SMB2 or later, CIFS does not support persistent handles */
2184 if (ctx->persistent) {
2185 if (ses->server->vals->protocol_id == 0) {
2186 cifs_dbg(VFS,
2187 "SMB3 or later required for persistent handles\n");
2188 rc = -EOPNOTSUPP;
2189 goto out_fail;
2190 } else if (ses->server->capabilities &
2191 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2192 tcon->use_persistent = true;
2193 else /* persistent handles requested but not supported */ {
2194 cifs_dbg(VFS,
2195 "Persistent handles not supported on share\n");
2196 rc = -EOPNOTSUPP;
2197 goto out_fail;
2198 }
2199 } else if ((tcon->capabilities & SMB2_SHARE_CAP_CONTINUOUS_AVAILABILITY)
2200 && (ses->server->capabilities & SMB2_GLOBAL_CAP_PERSISTENT_HANDLES)
2201 && (ctx->nopersistent == false)) {
2202 cifs_dbg(FYI, "enabling persistent handles\n");
2203 tcon->use_persistent = true;
2204 } else if (ctx->resilient) {
2205 if (ses->server->vals->protocol_id == 0) {
2206 cifs_dbg(VFS,
2207 "SMB2.1 or later required for resilient handles\n");
2208 rc = -EOPNOTSUPP;
2209 goto out_fail;
2210 }
2211 tcon->use_resilient = true;
2212 }
2213
2214 tcon->use_witness = false;
2215 if (IS_ENABLED(CONFIG_CIFS_SWN_UPCALL) && ctx->witness) {
2216 if (ses->server->vals->protocol_id >= SMB30_PROT_ID) {
2217 if (tcon->capabilities & SMB2_SHARE_CAP_CLUSTER) {
2218 /*
2219 * Set witness in use flag in first place
2220 * to retry registration in the echo task
2221 */
2222 tcon->use_witness = true;
2223 /* And try to register immediately */
2224 rc = cifs_swn_register(tcon);
2225 if (rc < 0) {
2226 cifs_dbg(VFS, "Failed to register for witness notifications: %d\n", rc);
2227 goto out_fail;
2228 }
2229 } else {
2230 /* TODO: try to extend for non-cluster uses (eg multichannel) */
2231 cifs_dbg(VFS, "witness requested on mount but no CLUSTER capability on share\n");
2232 rc = -EOPNOTSUPP;
2233 goto out_fail;
2234 }
2235 } else {
2236 cifs_dbg(VFS, "SMB3 or later required for witness option\n");
2237 rc = -EOPNOTSUPP;
2238 goto out_fail;
2239 }
2240 }
2241
2242 /* If the user really knows what they are doing they can override */
2243 if (tcon->share_flags & SMB2_SHAREFLAG_NO_CACHING) {
2244 if (ctx->cache_ro)
2245 cifs_dbg(VFS, "cache=ro requested on mount but NO_CACHING flag set on share\n");
2246 else if (ctx->cache_rw)
2247 cifs_dbg(VFS, "cache=singleclient requested on mount but NO_CACHING flag set on share\n");
2248 }
2249
2250 if (ctx->no_lease) {
2251 if (ses->server->vals->protocol_id == 0) {
2252 cifs_dbg(VFS,
2253 "SMB2 or later required for nolease option\n");
2254 rc = -EOPNOTSUPP;
2255 goto out_fail;
2256 } else
2257 tcon->no_lease = ctx->no_lease;
2258 }
2259
2260 /*
2261 * We can have only one retry value for a connection to a share so for
2262 * resources mounted more than once to the same server share the last
2263 * value passed in for the retry flag is used.
2264 */
2265 tcon->retry = ctx->retry;
2266 tcon->nocase = ctx->nocase;
2267 if (ses->server->capabilities & SMB2_GLOBAL_CAP_DIRECTORY_LEASING)
2268 tcon->nohandlecache = ctx->nohandlecache;
2269 else
2270 tcon->nohandlecache = true;
2271 tcon->nodelete = ctx->nodelete;
2272 tcon->local_lease = ctx->local_lease;
2273 INIT_LIST_HEAD(&tcon->pending_opens);
2274
2275 spin_lock(&cifs_tcp_ses_lock);
2276 list_add(&tcon->tcon_list, &ses->tcon_list);
2277 spin_unlock(&cifs_tcp_ses_lock);
2278
2279 cifs_fscache_get_super_cookie(tcon);
2280
2281 return tcon;
2282
2283out_fail:
2284 tconInfoFree(tcon);
2285 return ERR_PTR(rc);
2286}
2287
2288void
2289cifs_put_tlink(struct tcon_link *tlink)
2290{
2291 if (!tlink || IS_ERR(tlink))
2292 return;
2293
2294 if (!atomic_dec_and_test(&tlink->tl_count) ||
2295 test_bit(TCON_LINK_IN_TREE, &tlink->tl_flags)) {
2296 tlink->tl_time = jiffies;
2297 return;
2298 }
2299
2300 if (!IS_ERR(tlink_tcon(tlink)))
2301 cifs_put_tcon(tlink_tcon(tlink));
2302 kfree(tlink);
2303 return;
2304}
2305
2306static int
2307compare_mount_options(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2308{
2309 struct cifs_sb_info *old = CIFS_SB(sb);
2310 struct cifs_sb_info *new = mnt_data->cifs_sb;
2311 unsigned int oldflags = old->mnt_cifs_flags & CIFS_MOUNT_MASK;
2312 unsigned int newflags = new->mnt_cifs_flags & CIFS_MOUNT_MASK;
2313
2314 if ((sb->s_flags & CIFS_MS_MASK) != (mnt_data->flags & CIFS_MS_MASK))
2315 return 0;
2316
2317 if (old->mnt_cifs_serverino_autodisabled)
2318 newflags &= ~CIFS_MOUNT_SERVER_INUM;
2319
2320 if (oldflags != newflags)
2321 return 0;
2322
2323 /*
2324 * We want to share sb only if we don't specify an r/wsize or
2325 * specified r/wsize is greater than or equal to existing one.
2326 */
2327 if (new->ctx->wsize && new->ctx->wsize < old->ctx->wsize)
2328 return 0;
2329
2330 if (new->ctx->rsize && new->ctx->rsize < old->ctx->rsize)
2331 return 0;
2332
2333 if (!uid_eq(old->ctx->linux_uid, new->ctx->linux_uid) ||
2334 !gid_eq(old->ctx->linux_gid, new->ctx->linux_gid))
2335 return 0;
2336
2337 if (old->ctx->file_mode != new->ctx->file_mode ||
2338 old->ctx->dir_mode != new->ctx->dir_mode)
2339 return 0;
2340
2341 if (strcmp(old->local_nls->charset, new->local_nls->charset))
2342 return 0;
2343
2344 if (old->ctx->acregmax != new->ctx->acregmax)
2345 return 0;
2346 if (old->ctx->acdirmax != new->ctx->acdirmax)
2347 return 0;
2348
2349 return 1;
2350}
2351
2352static int
2353match_prepath(struct super_block *sb, struct cifs_mnt_data *mnt_data)
2354{
2355 struct cifs_sb_info *old = CIFS_SB(sb);
2356 struct cifs_sb_info *new = mnt_data->cifs_sb;
2357 bool old_set = (old->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2358 old->prepath;
2359 bool new_set = (new->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH) &&
2360 new->prepath;
2361
2362 if (old_set && new_set && !strcmp(new->prepath, old->prepath))
2363 return 1;
2364 else if (!old_set && !new_set)
2365 return 1;
2366
2367 return 0;
2368}
2369
2370int
2371cifs_match_super(struct super_block *sb, void *data)
2372{
2373 struct cifs_mnt_data *mnt_data = (struct cifs_mnt_data *)data;
2374 struct smb3_fs_context *ctx;
2375 struct cifs_sb_info *cifs_sb;
2376 struct TCP_Server_Info *tcp_srv;
2377 struct cifs_ses *ses;
2378 struct cifs_tcon *tcon;
2379 struct tcon_link *tlink;
2380 int rc = 0;
2381
2382 spin_lock(&cifs_tcp_ses_lock);
2383 cifs_sb = CIFS_SB(sb);
2384 tlink = cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
2385 if (tlink == NULL) {
2386 /* can not match superblock if tlink were ever null */
2387 spin_unlock(&cifs_tcp_ses_lock);
2388 return 0;
2389 }
2390 tcon = tlink_tcon(tlink);
2391 ses = tcon->ses;
2392 tcp_srv = ses->server;
2393
2394 ctx = mnt_data->ctx;
2395
2396 if (!match_server(tcp_srv, ctx) ||
2397 !match_session(ses, ctx) ||
2398 !match_tcon(tcon, ctx) ||
2399 !match_prepath(sb, mnt_data)) {
2400 rc = 0;
2401 goto out;
2402 }
2403
2404 rc = compare_mount_options(sb, mnt_data);
2405out:
2406 spin_unlock(&cifs_tcp_ses_lock);
2407 cifs_put_tlink(tlink);
2408 return rc;
2409}
2410
2411#ifdef CONFIG_DEBUG_LOCK_ALLOC
2412static struct lock_class_key cifs_key[2];
2413static struct lock_class_key cifs_slock_key[2];
2414
2415static inline void
2416cifs_reclassify_socket4(struct socket *sock)
2417{
2418 struct sock *sk = sock->sk;
2419 BUG_ON(!sock_allow_reclassification(sk));
2420 sock_lock_init_class_and_name(sk, "slock-AF_INET-CIFS",
2421 &cifs_slock_key[0], "sk_lock-AF_INET-CIFS", &cifs_key[0]);
2422}
2423
2424static inline void
2425cifs_reclassify_socket6(struct socket *sock)
2426{
2427 struct sock *sk = sock->sk;
2428 BUG_ON(!sock_allow_reclassification(sk));
2429 sock_lock_init_class_and_name(sk, "slock-AF_INET6-CIFS",
2430 &cifs_slock_key[1], "sk_lock-AF_INET6-CIFS", &cifs_key[1]);
2431}
2432#else
2433static inline void
2434cifs_reclassify_socket4(struct socket *sock)
2435{
2436}
2437
2438static inline void
2439cifs_reclassify_socket6(struct socket *sock)
2440{
2441}
2442#endif
2443
2444/* See RFC1001 section 14 on representation of Netbios names */
2445static void rfc1002mangle(char *target, char *source, unsigned int length)
2446{
2447 unsigned int i, j;
2448
2449 for (i = 0, j = 0; i < (length); i++) {
2450 /* mask a nibble at a time and encode */
2451 target[j] = 'A' + (0x0F & (source[i] >> 4));
2452 target[j+1] = 'A' + (0x0F & source[i]);
2453 j += 2;
2454 }
2455
2456}
2457
2458static int
2459bind_socket(struct TCP_Server_Info *server)
2460{
2461 int rc = 0;
2462 if (server->srcaddr.ss_family != AF_UNSPEC) {
2463 /* Bind to the specified local IP address */
2464 struct socket *socket = server->ssocket;
2465 rc = socket->ops->bind(socket,
2466 (struct sockaddr *) &server->srcaddr,
2467 sizeof(server->srcaddr));
2468 if (rc < 0) {
2469 struct sockaddr_in *saddr4;
2470 struct sockaddr_in6 *saddr6;
2471 saddr4 = (struct sockaddr_in *)&server->srcaddr;
2472 saddr6 = (struct sockaddr_in6 *)&server->srcaddr;
2473 if (saddr6->sin6_family == AF_INET6)
2474 cifs_server_dbg(VFS, "Failed to bind to: %pI6c, error: %d\n",
2475 &saddr6->sin6_addr, rc);
2476 else
2477 cifs_server_dbg(VFS, "Failed to bind to: %pI4, error: %d\n",
2478 &saddr4->sin_addr.s_addr, rc);
2479 }
2480 }
2481 return rc;
2482}
2483
2484static int
2485ip_rfc1001_connect(struct TCP_Server_Info *server)
2486{
2487 int rc = 0;
2488 /*
2489 * some servers require RFC1001 sessinit before sending
2490 * negprot - BB check reconnection in case where second
2491 * sessinit is sent but no second negprot
2492 */
2493 struct rfc1002_session_packet *ses_init_buf;
2494 struct smb_hdr *smb_buf;
2495 ses_init_buf = kzalloc(sizeof(struct rfc1002_session_packet),
2496 GFP_KERNEL);
2497 if (ses_init_buf) {
2498 ses_init_buf->trailer.session_req.called_len = 32;
2499
2500 if (server->server_RFC1001_name[0] != 0)
2501 rfc1002mangle(ses_init_buf->trailer.
2502 session_req.called_name,
2503 server->server_RFC1001_name,
2504 RFC1001_NAME_LEN_WITH_NULL);
2505 else
2506 rfc1002mangle(ses_init_buf->trailer.
2507 session_req.called_name,
2508 DEFAULT_CIFS_CALLED_NAME,
2509 RFC1001_NAME_LEN_WITH_NULL);
2510
2511 ses_init_buf->trailer.session_req.calling_len = 32;
2512
2513 /*
2514 * calling name ends in null (byte 16) from old smb
2515 * convention.
2516 */
2517 if (server->workstation_RFC1001_name[0] != 0)
2518 rfc1002mangle(ses_init_buf->trailer.
2519 session_req.calling_name,
2520 server->workstation_RFC1001_name,
2521 RFC1001_NAME_LEN_WITH_NULL);
2522 else
2523 rfc1002mangle(ses_init_buf->trailer.
2524 session_req.calling_name,
2525 "LINUX_CIFS_CLNT",
2526 RFC1001_NAME_LEN_WITH_NULL);
2527
2528 ses_init_buf->trailer.session_req.scope1 = 0;
2529 ses_init_buf->trailer.session_req.scope2 = 0;
2530 smb_buf = (struct smb_hdr *)ses_init_buf;
2531
2532 /* sizeof RFC1002_SESSION_REQUEST with no scope */
2533 smb_buf->smb_buf_length = cpu_to_be32(0x81000044);
2534 rc = smb_send(server, smb_buf, 0x44);
2535 kfree(ses_init_buf);
2536 /*
2537 * RFC1001 layer in at least one server
2538 * requires very short break before negprot
2539 * presumably because not expecting negprot
2540 * to follow so fast. This is a simple
2541 * solution that works without
2542 * complicating the code and causes no
2543 * significant slowing down on mount
2544 * for everyone else
2545 */
2546 usleep_range(1000, 2000);
2547 }
2548 /*
2549 * else the negprot may still work without this
2550 * even though malloc failed
2551 */
2552
2553 return rc;
2554}
2555
2556static int
2557generic_ip_connect(struct TCP_Server_Info *server)
2558{
2559 int rc = 0;
2560 __be16 sport;
2561 int slen, sfamily;
2562 struct socket *socket = server->ssocket;
2563 struct sockaddr *saddr;
2564
2565 saddr = (struct sockaddr *) &server->dstaddr;
2566
2567 if (server->dstaddr.ss_family == AF_INET6) {
2568 struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&server->dstaddr;
2569
2570 sport = ipv6->sin6_port;
2571 slen = sizeof(struct sockaddr_in6);
2572 sfamily = AF_INET6;
2573 cifs_dbg(FYI, "%s: connecting to [%pI6]:%d\n", __func__, &ipv6->sin6_addr,
2574 ntohs(sport));
2575 } else {
2576 struct sockaddr_in *ipv4 = (struct sockaddr_in *)&server->dstaddr;
2577
2578 sport = ipv4->sin_port;
2579 slen = sizeof(struct sockaddr_in);
2580 sfamily = AF_INET;
2581 cifs_dbg(FYI, "%s: connecting to %pI4:%d\n", __func__, &ipv4->sin_addr,
2582 ntohs(sport));
2583 }
2584
2585 if (socket == NULL) {
2586 rc = __sock_create(cifs_net_ns(server), sfamily, SOCK_STREAM,
2587 IPPROTO_TCP, &socket, 1);
2588 if (rc < 0) {
2589 cifs_server_dbg(VFS, "Error %d creating socket\n", rc);
2590 server->ssocket = NULL;
2591 return rc;
2592 }
2593
2594 /* BB other socket options to set KEEPALIVE, NODELAY? */
2595 cifs_dbg(FYI, "Socket created\n");
2596 server->ssocket = socket;
2597 socket->sk->sk_allocation = GFP_NOFS;
2598 if (sfamily == AF_INET6)
2599 cifs_reclassify_socket6(socket);
2600 else
2601 cifs_reclassify_socket4(socket);
2602 }
2603
2604 rc = bind_socket(server);
2605 if (rc < 0)
2606 return rc;
2607
2608 /*
2609 * Eventually check for other socket options to change from
2610 * the default. sock_setsockopt not used because it expects
2611 * user space buffer
2612 */
2613 socket->sk->sk_rcvtimeo = 7 * HZ;
2614 socket->sk->sk_sndtimeo = 5 * HZ;
2615
2616 /* make the bufsizes depend on wsize/rsize and max requests */
2617 if (server->noautotune) {
2618 if (socket->sk->sk_sndbuf < (200 * 1024))
2619 socket->sk->sk_sndbuf = 200 * 1024;
2620 if (socket->sk->sk_rcvbuf < (140 * 1024))
2621 socket->sk->sk_rcvbuf = 140 * 1024;
2622 }
2623
2624 if (server->tcp_nodelay)
2625 tcp_sock_set_nodelay(socket->sk);
2626
2627 cifs_dbg(FYI, "sndbuf %d rcvbuf %d rcvtimeo 0x%lx\n",
2628 socket->sk->sk_sndbuf,
2629 socket->sk->sk_rcvbuf, socket->sk->sk_rcvtimeo);
2630
2631 rc = socket->ops->connect(socket, saddr, slen,
2632 server->noblockcnt ? O_NONBLOCK : 0);
2633 /*
2634 * When mounting SMB root file systems, we do not want to block in
2635 * connect. Otherwise bail out and then let cifs_reconnect() perform
2636 * reconnect failover - if possible.
2637 */
2638 if (server->noblockcnt && rc == -EINPROGRESS)
2639 rc = 0;
2640 if (rc < 0) {
2641 cifs_dbg(FYI, "Error %d connecting to server\n", rc);
2642 sock_release(socket);
2643 server->ssocket = NULL;
2644 return rc;
2645 }
2646
2647 if (sport == htons(RFC1001_PORT))
2648 rc = ip_rfc1001_connect(server);
2649
2650 return rc;
2651}
2652
2653static int
2654ip_connect(struct TCP_Server_Info *server)
2655{
2656 __be16 *sport;
2657 struct sockaddr_in6 *addr6 = (struct sockaddr_in6 *)&server->dstaddr;
2658 struct sockaddr_in *addr = (struct sockaddr_in *)&server->dstaddr;
2659
2660 if (server->dstaddr.ss_family == AF_INET6)
2661 sport = &addr6->sin6_port;
2662 else
2663 sport = &addr->sin_port;
2664
2665 if (*sport == 0) {
2666 int rc;
2667
2668 /* try with 445 port at first */
2669 *sport = htons(CIFS_PORT);
2670
2671 rc = generic_ip_connect(server);
2672 if (rc >= 0)
2673 return rc;
2674
2675 /* if it failed, try with 139 port */
2676 *sport = htons(RFC1001_PORT);
2677 }
2678
2679 return generic_ip_connect(server);
2680}
2681
2682void reset_cifs_unix_caps(unsigned int xid, struct cifs_tcon *tcon,
2683 struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
2684{
2685 /*
2686 * If we are reconnecting then should we check to see if
2687 * any requested capabilities changed locally e.g. via
2688 * remount but we can not do much about it here
2689 * if they have (even if we could detect it by the following)
2690 * Perhaps we could add a backpointer to array of sb from tcon
2691 * or if we change to make all sb to same share the same
2692 * sb as NFS - then we only have one backpointer to sb.
2693 * What if we wanted to mount the server share twice once with
2694 * and once without posixacls or posix paths?
2695 */
2696 __u64 saved_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
2697
2698 if (ctx && ctx->no_linux_ext) {
2699 tcon->fsUnixInfo.Capability = 0;
2700 tcon->unix_ext = 0; /* Unix Extensions disabled */
2701 cifs_dbg(FYI, "Linux protocol extensions disabled\n");
2702 return;
2703 } else if (ctx)
2704 tcon->unix_ext = 1; /* Unix Extensions supported */
2705
2706 if (!tcon->unix_ext) {
2707 cifs_dbg(FYI, "Unix extensions disabled so not set on reconnect\n");
2708 return;
2709 }
2710
2711 if (!CIFSSMBQFSUnixInfo(xid, tcon)) {
2712 __u64 cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
2713 cifs_dbg(FYI, "unix caps which server supports %lld\n", cap);
2714 /*
2715 * check for reconnect case in which we do not
2716 * want to change the mount behavior if we can avoid it
2717 */
2718 if (ctx == NULL) {
2719 /*
2720 * turn off POSIX ACL and PATHNAMES if not set
2721 * originally at mount time
2722 */
2723 if ((saved_cap & CIFS_UNIX_POSIX_ACL_CAP) == 0)
2724 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
2725 if ((saved_cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
2726 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
2727 cifs_dbg(VFS, "POSIXPATH support change\n");
2728 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
2729 } else if ((cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) == 0) {
2730 cifs_dbg(VFS, "possible reconnect error\n");
2731 cifs_dbg(VFS, "server disabled POSIX path support\n");
2732 }
2733 }
2734
2735 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
2736 cifs_dbg(VFS, "per-share encryption not supported yet\n");
2737
2738 cap &= CIFS_UNIX_CAP_MASK;
2739 if (ctx && ctx->no_psx_acl)
2740 cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
2741 else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
2742 cifs_dbg(FYI, "negotiated posix acl support\n");
2743 if (cifs_sb)
2744 cifs_sb->mnt_cifs_flags |=
2745 CIFS_MOUNT_POSIXACL;
2746 }
2747
2748 if (ctx && ctx->posix_paths == 0)
2749 cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
2750 else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
2751 cifs_dbg(FYI, "negotiate posix pathnames\n");
2752 if (cifs_sb)
2753 cifs_sb->mnt_cifs_flags |=
2754 CIFS_MOUNT_POSIX_PATHS;
2755 }
2756
2757 cifs_dbg(FYI, "Negotiate caps 0x%x\n", (int)cap);
2758#ifdef CONFIG_CIFS_DEBUG2
2759 if (cap & CIFS_UNIX_FCNTL_CAP)
2760 cifs_dbg(FYI, "FCNTL cap\n");
2761 if (cap & CIFS_UNIX_EXTATTR_CAP)
2762 cifs_dbg(FYI, "EXTATTR cap\n");
2763 if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP)
2764 cifs_dbg(FYI, "POSIX path cap\n");
2765 if (cap & CIFS_UNIX_XATTR_CAP)
2766 cifs_dbg(FYI, "XATTR cap\n");
2767 if (cap & CIFS_UNIX_POSIX_ACL_CAP)
2768 cifs_dbg(FYI, "POSIX ACL cap\n");
2769 if (cap & CIFS_UNIX_LARGE_READ_CAP)
2770 cifs_dbg(FYI, "very large read cap\n");
2771 if (cap & CIFS_UNIX_LARGE_WRITE_CAP)
2772 cifs_dbg(FYI, "very large write cap\n");
2773 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_CAP)
2774 cifs_dbg(FYI, "transport encryption cap\n");
2775 if (cap & CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)
2776 cifs_dbg(FYI, "mandatory transport encryption cap\n");
2777#endif /* CIFS_DEBUG2 */
2778 if (CIFSSMBSetFSUnixInfo(xid, tcon, cap)) {
2779 if (ctx == NULL)
2780 cifs_dbg(FYI, "resetting capabilities failed\n");
2781 else
2782 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");
2783
2784 }
2785 }
2786}
2787
2788int cifs_setup_cifs_sb(struct cifs_sb_info *cifs_sb)
2789{
2790 struct smb3_fs_context *ctx = cifs_sb->ctx;
2791
2792 INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
2793
2794 spin_lock_init(&cifs_sb->tlink_tree_lock);
2795 cifs_sb->tlink_tree = RB_ROOT;
2796
2797 cifs_dbg(FYI, "file mode: %04ho dir mode: %04ho\n",
2798 ctx->file_mode, ctx->dir_mode);
2799
2800 /* this is needed for ASCII cp to Unicode converts */
2801 if (ctx->iocharset == NULL) {
2802 /* load_nls_default cannot return null */
2803 cifs_sb->local_nls = load_nls_default();
2804 } else {
2805 cifs_sb->local_nls = load_nls(ctx->iocharset);
2806 if (cifs_sb->local_nls == NULL) {
2807 cifs_dbg(VFS, "CIFS mount error: iocharset %s not found\n",
2808 ctx->iocharset);
2809 return -ELIBACC;
2810 }
2811 }
2812 ctx->local_nls = cifs_sb->local_nls;
2813
2814 smb3_update_mnt_flags(cifs_sb);
2815
2816 if (ctx->direct_io)
2817 cifs_dbg(FYI, "mounting share using direct i/o\n");
2818 if (ctx->cache_ro) {
2819 cifs_dbg(VFS, "mounting share with read only caching. Ensure that the share will not be modified while in use.\n");
2820 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RO_CACHE;
2821 } else if (ctx->cache_rw) {
2822 cifs_dbg(VFS, "mounting share in single client RW caching mode. Ensure that no other systems will be accessing the share.\n");
2823 cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_RO_CACHE |
2824 CIFS_MOUNT_RW_CACHE);
2825 }
2826
2827 if ((ctx->cifs_acl) && (ctx->dynperm))
2828 cifs_dbg(VFS, "mount option dynperm ignored if cifsacl mount option supported\n");
2829
2830 if (ctx->prepath) {
2831 cifs_sb->prepath = kstrdup(ctx->prepath, GFP_KERNEL);
2832 if (cifs_sb->prepath == NULL)
2833 return -ENOMEM;
2834 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
2835 }
2836
2837 return 0;
2838}
2839
2840/* Release all succeed connections */
2841static inline void mount_put_conns(struct cifs_sb_info *cifs_sb,
2842 unsigned int xid,
2843 struct TCP_Server_Info *server,
2844 struct cifs_ses *ses, struct cifs_tcon *tcon)
2845{
2846 int rc = 0;
2847
2848 if (tcon)
2849 cifs_put_tcon(tcon);
2850 else if (ses)
2851 cifs_put_smb_ses(ses);
2852 else if (server)
2853 cifs_put_tcp_session(server, 0);
2854 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_POSIX_PATHS;
2855 free_xid(xid);
2856}
2857
2858/* Get connections for tcp, ses and tcon */
2859static int mount_get_conns(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
2860 unsigned int *xid,
2861 struct TCP_Server_Info **nserver,
2862 struct cifs_ses **nses, struct cifs_tcon **ntcon)
2863{
2864 int rc = 0;
2865 struct TCP_Server_Info *server;
2866 struct cifs_ses *ses;
2867 struct cifs_tcon *tcon;
2868
2869 *nserver = NULL;
2870 *nses = NULL;
2871 *ntcon = NULL;
2872
2873 *xid = get_xid();
2874
2875 /* get a reference to a tcp session */
2876 server = cifs_get_tcp_session(ctx);
2877 if (IS_ERR(server)) {
2878 rc = PTR_ERR(server);
2879 return rc;
2880 }
2881
2882 *nserver = server;
2883
2884 /* get a reference to a SMB session */
2885 ses = cifs_get_smb_ses(server, ctx);
2886 if (IS_ERR(ses)) {
2887 rc = PTR_ERR(ses);
2888 return rc;
2889 }
2890
2891 *nses = ses;
2892
2893 if ((ctx->persistent == true) && (!(ses->server->capabilities &
2894 SMB2_GLOBAL_CAP_PERSISTENT_HANDLES))) {
2895 cifs_server_dbg(VFS, "persistent handles not supported by server\n");
2896 return -EOPNOTSUPP;
2897 }
2898
2899 /* search for existing tcon to this server share */
2900 tcon = cifs_get_tcon(ses, ctx);
2901 if (IS_ERR(tcon)) {
2902 rc = PTR_ERR(tcon);
2903 return rc;
2904 }
2905
2906 *ntcon = tcon;
2907
2908 /* if new SMB3.11 POSIX extensions are supported do not remap / and \ */
2909 if (tcon->posix_extensions)
2910 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_POSIX_PATHS;
2911
2912 /* tell server which Unix caps we support */
2913 if (cap_unix(tcon->ses)) {
2914 /*
2915 * reset of caps checks mount to see if unix extensions disabled
2916 * for just this mount.
2917 */
2918 reset_cifs_unix_caps(*xid, tcon, cifs_sb, ctx);
2919 if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
2920 (le64_to_cpu(tcon->fsUnixInfo.Capability) &
2921 CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP))
2922 return -EACCES;
2923 } else
2924 tcon->unix_ext = 0; /* server does not support them */
2925
2926 /* do not care if a following call succeed - informational */
2927 if (!tcon->pipe && server->ops->qfs_tcon) {
2928 server->ops->qfs_tcon(*xid, tcon, cifs_sb);
2929 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_RO_CACHE) {
2930 if (tcon->fsDevInfo.DeviceCharacteristics &
2931 cpu_to_le32(FILE_READ_ONLY_DEVICE))
2932 cifs_dbg(VFS, "mounted to read only share\n");
2933 else if ((cifs_sb->mnt_cifs_flags &
2934 CIFS_MOUNT_RW_CACHE) == 0)
2935 cifs_dbg(VFS, "read only mount of RW share\n");
2936 /* no need to log a RW mount of a typical RW share */
2937 }
2938 }
2939
2940 /*
2941 * Clamp the rsize/wsize mount arguments if they are too big for the server
2942 * and set the rsize/wsize to the negotiated values if not passed in by
2943 * the user on mount
2944 */
2945 if ((cifs_sb->ctx->wsize == 0) ||
2946 (cifs_sb->ctx->wsize > server->ops->negotiate_wsize(tcon, ctx)))
2947 cifs_sb->ctx->wsize = server->ops->negotiate_wsize(tcon, ctx);
2948 if ((cifs_sb->ctx->rsize == 0) ||
2949 (cifs_sb->ctx->rsize > server->ops->negotiate_rsize(tcon, ctx)))
2950 cifs_sb->ctx->rsize = server->ops->negotiate_rsize(tcon, ctx);
2951
2952 return 0;
2953}
2954
2955static int mount_setup_tlink(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
2956 struct cifs_tcon *tcon)
2957{
2958 struct tcon_link *tlink;
2959
2960 /* hang the tcon off of the superblock */
2961 tlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
2962 if (tlink == NULL)
2963 return -ENOMEM;
2964
2965 tlink->tl_uid = ses->linux_uid;
2966 tlink->tl_tcon = tcon;
2967 tlink->tl_time = jiffies;
2968 set_bit(TCON_LINK_MASTER, &tlink->tl_flags);
2969 set_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
2970
2971 cifs_sb->master_tlink = tlink;
2972 spin_lock(&cifs_sb->tlink_tree_lock);
2973 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
2974 spin_unlock(&cifs_sb->tlink_tree_lock);
2975
2976 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
2977 TLINK_IDLE_EXPIRE);
2978 return 0;
2979}
2980
2981#ifdef CONFIG_CIFS_DFS_UPCALL
2982static int mount_get_dfs_conns(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
2983 unsigned int *xid, struct TCP_Server_Info **nserver,
2984 struct cifs_ses **nses, struct cifs_tcon **ntcon)
2985{
2986 int rc;
2987
2988 ctx->nosharesock = true;
2989 rc = mount_get_conns(ctx, cifs_sb, xid, nserver, nses, ntcon);
2990 if (*nserver) {
2991 cifs_dbg(FYI, "%s: marking tcp session as a dfs connection\n", __func__);
2992 spin_lock(&cifs_tcp_ses_lock);
2993 (*nserver)->is_dfs_conn = true;
2994 spin_unlock(&cifs_tcp_ses_lock);
2995 }
2996 return rc;
2997}
2998
2999/*
3000 * cifs_build_path_to_root returns full path to root when we do not have an
3001 * existing connection (tcon)
3002 */
3003static char *
3004build_unc_path_to_root(const struct smb3_fs_context *ctx,
3005 const struct cifs_sb_info *cifs_sb, bool useppath)
3006{
3007 char *full_path, *pos;
3008 unsigned int pplen = useppath && ctx->prepath ?
3009 strlen(ctx->prepath) + 1 : 0;
3010 unsigned int unc_len = strnlen(ctx->UNC, MAX_TREE_SIZE + 1);
3011
3012 if (unc_len > MAX_TREE_SIZE)
3013 return ERR_PTR(-EINVAL);
3014
3015 full_path = kmalloc(unc_len + pplen + 1, GFP_KERNEL);
3016 if (full_path == NULL)
3017 return ERR_PTR(-ENOMEM);
3018
3019 memcpy(full_path, ctx->UNC, unc_len);
3020 pos = full_path + unc_len;
3021
3022 if (pplen) {
3023 *pos = CIFS_DIR_SEP(cifs_sb);
3024 memcpy(pos + 1, ctx->prepath, pplen);
3025 pos += pplen;
3026 }
3027
3028 *pos = '\0'; /* add trailing null */
3029 convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
3030 cifs_dbg(FYI, "%s: full_path=%s\n", __func__, full_path);
3031 return full_path;
3032}
3033
3034/**
3035 * expand_dfs_referral - Perform a dfs referral query and update the cifs_sb
3036 *
3037 * If a referral is found, cifs_sb->ctx->mount_options will be (re-)allocated
3038 * to a string containing updated options for the submount. Otherwise it
3039 * will be left untouched.
3040 *
3041 * Returns the rc from get_dfs_path to the caller, which can be used to
3042 * determine whether there were referrals.
3043 */
3044static int
3045expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
3046 struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
3047 char *ref_path)
3048{
3049 int rc;
3050 struct dfs_info3_param referral = {0};
3051 char *full_path = NULL, *mdata = NULL;
3052
3053 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
3054 return -EREMOTE;
3055
3056 full_path = build_unc_path_to_root(ctx, cifs_sb, true);
3057 if (IS_ERR(full_path))
3058 return PTR_ERR(full_path);
3059
3060 rc = dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb),
3061 ref_path, &referral, NULL);
3062 if (!rc) {
3063 char *fake_devname = NULL;
3064
3065 mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options,
3066 full_path + 1, &referral,
3067 &fake_devname);
3068 free_dfs_info_param(&referral);
3069
3070 if (IS_ERR(mdata)) {
3071 rc = PTR_ERR(mdata);
3072 mdata = NULL;
3073 } else {
3074 /*
3075 * We can not clear out the whole structure since we
3076 * no longer have an explicit function to parse
3077 * a mount-string. Instead we need to clear out the
3078 * individual fields that are no longer valid.
3079 */
3080 kfree(ctx->prepath);
3081 ctx->prepath = NULL;
3082 rc = cifs_setup_volume_info(ctx, mdata, fake_devname);
3083 }
3084 kfree(fake_devname);
3085 kfree(cifs_sb->ctx->mount_options);
3086 cifs_sb->ctx->mount_options = mdata;
3087 }
3088 kfree(full_path);
3089 return rc;
3090}
3091
3092static int get_next_dfs_tgt(struct dfs_cache_tgt_list *tgt_list,
3093 struct dfs_cache_tgt_iterator **tgt_it)
3094{
3095 if (!*tgt_it)
3096 *tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
3097 else
3098 *tgt_it = dfs_cache_get_next_tgt(tgt_list, *tgt_it);
3099 return !*tgt_it ? -EHOSTDOWN : 0;
3100}
3101
3102static int update_vol_info(const struct dfs_cache_tgt_iterator *tgt_it,
3103 struct smb3_fs_context *fake_ctx, struct smb3_fs_context *ctx)
3104{
3105 const char *tgt = dfs_cache_get_tgt_name(tgt_it);
3106 int len = strlen(tgt) + 2;
3107 char *new_unc;
3108
3109 new_unc = kmalloc(len, GFP_KERNEL);
3110 if (!new_unc)
3111 return -ENOMEM;
3112 scnprintf(new_unc, len, "\\%s", tgt);
3113
3114 kfree(ctx->UNC);
3115 ctx->UNC = new_unc;
3116
3117 if (fake_ctx->prepath) {
3118 kfree(ctx->prepath);
3119 ctx->prepath = fake_ctx->prepath;
3120 fake_ctx->prepath = NULL;
3121 }
3122 memcpy(&ctx->dstaddr, &fake_ctx->dstaddr, sizeof(ctx->dstaddr));
3123
3124 return 0;
3125}
3126
3127static int do_dfs_failover(const char *path, const char *full_path, struct cifs_sb_info *cifs_sb,
3128 struct smb3_fs_context *ctx, struct cifs_ses *root_ses,
3129 unsigned int *xid, struct TCP_Server_Info **server,
3130 struct cifs_ses **ses, struct cifs_tcon **tcon)
3131{
3132 int rc;
3133 char *npath = NULL;
3134 struct dfs_cache_tgt_list tgt_list = DFS_CACHE_TGT_LIST_INIT(tgt_list);
3135 struct dfs_cache_tgt_iterator *tgt_it = NULL;
3136 struct smb3_fs_context tmp_ctx = {NULL};
3137
3138 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
3139 return -EOPNOTSUPP;
3140
3141 npath = dfs_cache_canonical_path(path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3142 if (IS_ERR(npath))
3143 return PTR_ERR(npath);
3144
3145 cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, npath, full_path);
3146
3147 rc = dfs_cache_noreq_find(npath, NULL, &tgt_list);
3148 if (rc)
3149 goto out;
3150 /*
3151 * We use a 'tmp_ctx' here because we need pass it down to the mount_{get,put} functions to
3152 * test connection against new DFS targets.
3153 */
3154 rc = smb3_fs_context_dup(&tmp_ctx, ctx);
3155 if (rc)
3156 goto out;
3157
3158 for (;;) {
3159 struct dfs_info3_param ref = {0};
3160 char *fake_devname = NULL, *mdata = NULL;
3161
3162 /* Get next DFS target server - if any */
3163 rc = get_next_dfs_tgt(&tgt_list, &tgt_it);
3164 if (rc)
3165 break;
3166
3167 rc = dfs_cache_get_tgt_referral(npath, tgt_it, &ref);
3168 if (rc)
3169 break;
3170
3171 cifs_dbg(FYI, "%s: old ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3172 tmp_ctx.prepath);
3173
3174 mdata = cifs_compose_mount_options(cifs_sb->ctx->mount_options, full_path + 1, &ref,
3175 &fake_devname);
3176 free_dfs_info_param(&ref);
3177
3178 if (IS_ERR(mdata)) {
3179 rc = PTR_ERR(mdata);
3180 mdata = NULL;
3181 } else
3182 rc = cifs_setup_volume_info(&tmp_ctx, mdata, fake_devname);
3183
3184 kfree(mdata);
3185 kfree(fake_devname);
3186
3187 if (rc)
3188 break;
3189
3190 cifs_dbg(FYI, "%s: new ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3191 tmp_ctx.prepath);
3192
3193 mount_put_conns(cifs_sb, *xid, *server, *ses, *tcon);
3194 rc = mount_get_dfs_conns(&tmp_ctx, cifs_sb, xid, server, ses, tcon);
3195 if (!rc || (*server && *ses)) {
3196 /*
3197 * We were able to connect to new target server. Update current context with
3198 * new target server.
3199 */
3200 rc = update_vol_info(tgt_it, &tmp_ctx, ctx);
3201 break;
3202 }
3203 }
3204 if (!rc) {
3205 cifs_dbg(FYI, "%s: final ctx: UNC=%s prepath=%s\n", __func__, tmp_ctx.UNC,
3206 tmp_ctx.prepath);
3207 /*
3208 * Update DFS target hint in DFS referral cache with the target server we
3209 * successfully reconnected to.
3210 */
3211 rc = dfs_cache_update_tgthint(*xid, root_ses ? root_ses : *ses, cifs_sb->local_nls,
3212 cifs_remap(cifs_sb), path, tgt_it);
3213 }
3214
3215out:
3216 kfree(npath);
3217 smb3_cleanup_fs_context_contents(&tmp_ctx);
3218 dfs_cache_free_tgts(&tgt_list);
3219 return rc;
3220}
3221#endif
3222
3223/* TODO: all callers to this are broken. We are not parsing mount_options here
3224 * we should pass a clone of the original context?
3225 */
3226int
3227cifs_setup_volume_info(struct smb3_fs_context *ctx, const char *mntopts, const char *devname)
3228{
3229 int rc;
3230
3231 if (devname) {
3232 cifs_dbg(FYI, "%s: devname=%s\n", __func__, devname);
3233 rc = smb3_parse_devname(devname, ctx);
3234 if (rc) {
3235 cifs_dbg(VFS, "%s: failed to parse %s: %d\n", __func__, devname, rc);
3236 return rc;
3237 }
3238 }
3239
3240 if (mntopts) {
3241 char *ip;
3242
3243 rc = smb3_parse_opt(mntopts, "ip", &ip);
3244 if (rc) {
3245 cifs_dbg(VFS, "%s: failed to parse ip options: %d\n", __func__, rc);
3246 return rc;
3247 }
3248
3249 rc = cifs_convert_address((struct sockaddr *)&ctx->dstaddr, ip, strlen(ip));
3250 kfree(ip);
3251 if (!rc) {
3252 cifs_dbg(VFS, "%s: failed to convert ip address\n", __func__);
3253 return -EINVAL;
3254 }
3255 }
3256
3257 if (ctx->nullauth) {
3258 cifs_dbg(FYI, "Anonymous login\n");
3259 kfree(ctx->username);
3260 ctx->username = NULL;
3261 } else if (ctx->username) {
3262 /* BB fixme parse for domain name here */
3263 cifs_dbg(FYI, "Username: %s\n", ctx->username);
3264 } else {
3265 cifs_dbg(VFS, "No username specified\n");
3266 /* In userspace mount helper we can get user name from alternate
3267 locations such as env variables and files on disk */
3268 return -EINVAL;
3269 }
3270
3271 return 0;
3272}
3273
3274static int
3275cifs_are_all_path_components_accessible(struct TCP_Server_Info *server,
3276 unsigned int xid,
3277 struct cifs_tcon *tcon,
3278 struct cifs_sb_info *cifs_sb,
3279 char *full_path,
3280 int added_treename)
3281{
3282 int rc;
3283 char *s;
3284 char sep, tmp;
3285 int skip = added_treename ? 1 : 0;
3286
3287 sep = CIFS_DIR_SEP(cifs_sb);
3288 s = full_path;
3289
3290 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb, "");
3291 while (rc == 0) {
3292 /* skip separators */
3293 while (*s == sep)
3294 s++;
3295 if (!*s)
3296 break;
3297 /* next separator */
3298 while (*s && *s != sep)
3299 s++;
3300 /*
3301 * if the treename is added, we then have to skip the first
3302 * part within the separators
3303 */
3304 if (skip) {
3305 skip = 0;
3306 continue;
3307 }
3308 /*
3309 * temporarily null-terminate the path at the end of
3310 * the current component
3311 */
3312 tmp = *s;
3313 *s = 0;
3314 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3315 full_path);
3316 *s = tmp;
3317 }
3318 return rc;
3319}
3320
3321/*
3322 * Check if path is remote (e.g. a DFS share). Return -EREMOTE if it is,
3323 * otherwise 0.
3324 */
3325static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
3326 const unsigned int xid,
3327 struct TCP_Server_Info *server,
3328 struct cifs_tcon *tcon)
3329{
3330 int rc;
3331 char *full_path;
3332
3333 if (!server->ops->is_path_accessible)
3334 return -EOPNOTSUPP;
3335
3336 /*
3337 * cifs_build_path_to_root works only when we have a valid tcon
3338 */
3339 full_path = cifs_build_path_to_root(ctx, cifs_sb, tcon,
3340 tcon->Flags & SMB_SHARE_IS_IN_DFS);
3341 if (full_path == NULL)
3342 return -ENOMEM;
3343
3344 cifs_dbg(FYI, "%s: full_path: %s\n", __func__, full_path);
3345
3346 rc = server->ops->is_path_accessible(xid, tcon, cifs_sb,
3347 full_path);
3348 if (rc != 0 && rc != -EREMOTE) {
3349 kfree(full_path);
3350 return rc;
3351 }
3352
3353 if (rc != -EREMOTE) {
3354 rc = cifs_are_all_path_components_accessible(server, xid, tcon,
3355 cifs_sb, full_path, tcon->Flags & SMB_SHARE_IS_IN_DFS);
3356 if (rc != 0) {
3357 cifs_server_dbg(VFS, "cannot query dirs between root and final path, enabling CIFS_MOUNT_USE_PREFIX_PATH\n");
3358 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3359 rc = 0;
3360 }
3361 }
3362
3363 kfree(full_path);
3364 return rc;
3365}
3366
3367#ifdef CONFIG_CIFS_DFS_UPCALL
3368static void set_root_ses(struct cifs_sb_info *cifs_sb, const uuid_t *mount_id, struct cifs_ses *ses,
3369 struct cifs_ses **root_ses)
3370{
3371 if (ses) {
3372 spin_lock(&cifs_tcp_ses_lock);
3373 ses->ses_count++;
3374 spin_unlock(&cifs_tcp_ses_lock);
3375 dfs_cache_add_refsrv_session(mount_id, ses);
3376 }
3377 *root_ses = ses;
3378}
3379
3380/* Set up next dfs prefix path in @dfs_path */
3381static int next_dfs_prepath(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
3382 const unsigned int xid, struct TCP_Server_Info *server,
3383 struct cifs_tcon *tcon, char **dfs_path)
3384{
3385 char *path, *npath;
3386 int added_treename = is_tcon_dfs(tcon);
3387 int rc;
3388
3389 path = cifs_build_path_to_root(ctx, cifs_sb, tcon, added_treename);
3390 if (!path)
3391 return -ENOMEM;
3392
3393 rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3394 if (rc == -EREMOTE) {
3395 struct smb3_fs_context v = {NULL};
3396 /* if @path contains a tree name, skip it in the prefix path */
3397 if (added_treename) {
3398 rc = smb3_parse_devname(path, &v);
3399 if (rc)
3400 goto out;
3401 npath = build_unc_path_to_root(&v, cifs_sb, true);
3402 smb3_cleanup_fs_context_contents(&v);
3403 } else {
3404 v.UNC = ctx->UNC;
3405 v.prepath = path + 1;
3406 npath = build_unc_path_to_root(&v, cifs_sb, true);
3407 }
3408
3409 if (IS_ERR(npath)) {
3410 rc = PTR_ERR(npath);
3411 goto out;
3412 }
3413
3414 kfree(*dfs_path);
3415 *dfs_path = npath;
3416 rc = -EREMOTE;
3417 }
3418
3419out:
3420 kfree(path);
3421 return rc;
3422}
3423
3424/* Check if resolved targets can handle any DFS referrals */
3425static int is_referral_server(const char *ref_path, struct cifs_sb_info *cifs_sb,
3426 struct cifs_tcon *tcon, bool *ref_server)
3427{
3428 int rc;
3429 struct dfs_info3_param ref = {0};
3430
3431 cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
3432
3433 if (is_tcon_dfs(tcon)) {
3434 *ref_server = true;
3435 } else {
3436 char *npath;
3437
3438 npath = dfs_cache_canonical_path(ref_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3439 if (IS_ERR(npath))
3440 return PTR_ERR(npath);
3441
3442 rc = dfs_cache_noreq_find(npath, &ref, NULL);
3443 kfree(npath);
3444 if (rc) {
3445 cifs_dbg(VFS, "%s: dfs_cache_noreq_find: failed (rc=%d)\n", __func__, rc);
3446 return rc;
3447 }
3448 cifs_dbg(FYI, "%s: ref.flags=0x%x\n", __func__, ref.flags);
3449 /*
3450 * Check if all targets are capable of handling DFS referrals as per
3451 * MS-DFSC 2.2.4 RESP_GET_DFS_REFERRAL.
3452 */
3453 *ref_server = !!(ref.flags & DFSREF_REFERRAL_SERVER);
3454 free_dfs_info_param(&ref);
3455 }
3456 return 0;
3457}
3458
3459int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3460{
3461 int rc = 0;
3462 unsigned int xid;
3463 struct TCP_Server_Info *server = NULL;
3464 struct cifs_ses *ses = NULL, *root_ses = NULL;
3465 struct cifs_tcon *tcon = NULL;
3466 int count = 0;
3467 uuid_t mount_id = {0};
3468 char *ref_path = NULL, *full_path = NULL;
3469 char *oldmnt = NULL;
3470 bool ref_server = false;
3471
3472 rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3473 /*
3474 * If called with 'nodfs' mount option, then skip DFS resolving. Otherwise unconditionally
3475 * try to get an DFS referral (even cached) to determine whether it is an DFS mount.
3476 *
3477 * Skip prefix path to provide support for DFS referrals from w2k8 servers which don't seem
3478 * to respond with PATH_NOT_COVERED to requests that include the prefix.
3479 */
3480 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) ||
3481 dfs_cache_find(xid, ses, cifs_sb->local_nls, cifs_remap(cifs_sb), ctx->UNC + 1, NULL,
3482 NULL)) {
3483 if (rc)
3484 goto error;
3485 /* Check if it is fully accessible and then mount it */
3486 rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3487 if (!rc)
3488 goto out;
3489 if (rc != -EREMOTE)
3490 goto error;
3491 }
3492
3493 mount_put_conns(cifs_sb, xid, server, ses, tcon);
3494 /*
3495 * Ignore error check here because we may failover to other targets from cached a
3496 * referral.
3497 */
3498 (void)mount_get_dfs_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3499
3500 /* Get path of DFS root */
3501 ref_path = build_unc_path_to_root(ctx, cifs_sb, false);
3502 if (IS_ERR(ref_path)) {
3503 rc = PTR_ERR(ref_path);
3504 ref_path = NULL;
3505 goto error;
3506 }
3507
3508 uuid_gen(&mount_id);
3509 set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
3510 do {
3511 /* Save full path of last DFS path we used to resolve final target server */
3512 kfree(full_path);
3513 full_path = build_unc_path_to_root(ctx, cifs_sb, !!count);
3514 if (IS_ERR(full_path)) {
3515 rc = PTR_ERR(full_path);
3516 full_path = NULL;
3517 break;
3518 }
3519 /* Chase referral */
3520 oldmnt = cifs_sb->ctx->mount_options;
3521 rc = expand_dfs_referral(xid, root_ses, ctx, cifs_sb, ref_path + 1);
3522 if (rc)
3523 break;
3524 /* Connect to new DFS target only if we were redirected */
3525 if (oldmnt != cifs_sb->ctx->mount_options) {
3526 mount_put_conns(cifs_sb, xid, server, ses, tcon);
3527 rc = mount_get_dfs_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3528 }
3529 if (rc && !server && !ses) {
3530 /* Failed to connect. Try to connect to other targets in the referral. */
3531 rc = do_dfs_failover(ref_path + 1, full_path, cifs_sb, ctx, root_ses, &xid,
3532 &server, &ses, &tcon);
3533 }
3534 if (rc == -EACCES || rc == -EOPNOTSUPP || !server || !ses)
3535 break;
3536 if (!tcon)
3537 continue;
3538
3539 /* Make sure that requests go through new root servers */
3540 rc = is_referral_server(ref_path + 1, cifs_sb, tcon, &ref_server);
3541 if (rc)
3542 break;
3543 if (ref_server)
3544 set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
3545
3546 /* Get next dfs path and then continue chasing them if -EREMOTE */
3547 rc = next_dfs_prepath(cifs_sb, ctx, xid, server, tcon, &ref_path);
3548 /* Prevent recursion on broken link referrals */
3549 if (rc == -EREMOTE && ++count > MAX_NESTED_LINKS)
3550 rc = -ELOOP;
3551 } while (rc == -EREMOTE);
3552
3553 if (rc || !tcon || !ses)
3554 goto error;
3555
3556 kfree(ref_path);
3557 /*
3558 * Store DFS full path in both superblock and tree connect structures.
3559 *
3560 * For DFS root mounts, the prefix path (cifs_sb->prepath) is preserved during reconnect so
3561 * only the root path is set in cifs_sb->origin_fullpath and tcon->dfs_path. And for DFS
3562 * links, the prefix path is included in both and may be changed during reconnect. See
3563 * cifs_tree_connect().
3564 */
3565 ref_path = dfs_cache_canonical_path(full_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
3566 kfree(full_path);
3567 full_path = NULL;
3568
3569 if (IS_ERR(ref_path)) {
3570 rc = PTR_ERR(ref_path);
3571 ref_path = NULL;
3572 goto error;
3573 }
3574 cifs_sb->origin_fullpath = ref_path;
3575
3576 ref_path = kstrdup(cifs_sb->origin_fullpath, GFP_KERNEL);
3577 if (!ref_path) {
3578 rc = -ENOMEM;
3579 goto error;
3580 }
3581 spin_lock(&cifs_tcp_ses_lock);
3582 tcon->dfs_path = ref_path;
3583 ref_path = NULL;
3584 spin_unlock(&cifs_tcp_ses_lock);
3585
3586 /*
3587 * After reconnecting to a different server, unique ids won't
3588 * match anymore, so we disable serverino. This prevents
3589 * dentry revalidation to think the dentry are stale (ESTALE).
3590 */
3591 cifs_autodisable_serverino(cifs_sb);
3592 /*
3593 * Force the use of prefix path to support failover on DFS paths that
3594 * resolve to targets that have different prefix paths.
3595 */
3596 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
3597 kfree(cifs_sb->prepath);
3598 cifs_sb->prepath = ctx->prepath;
3599 ctx->prepath = NULL;
3600 uuid_copy(&cifs_sb->dfs_mount_id, &mount_id);
3601
3602out:
3603 free_xid(xid);
3604 cifs_try_adding_channels(cifs_sb, ses);
3605 return mount_setup_tlink(cifs_sb, ses, tcon);
3606
3607error:
3608 kfree(ref_path);
3609 kfree(full_path);
3610 kfree(cifs_sb->origin_fullpath);
3611 dfs_cache_put_refsrv_sessions(&mount_id);
3612 mount_put_conns(cifs_sb, xid, server, ses, tcon);
3613 return rc;
3614}
3615#else
3616int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
3617{
3618 int rc = 0;
3619 unsigned int xid;
3620 struct cifs_ses *ses;
3621 struct cifs_tcon *tcon;
3622 struct TCP_Server_Info *server;
3623
3624 rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
3625 if (rc)
3626 goto error;
3627
3628 if (tcon) {
3629 rc = is_path_remote(cifs_sb, ctx, xid, server, tcon);
3630 if (rc == -EREMOTE)
3631 rc = -EOPNOTSUPP;
3632 if (rc)
3633 goto error;
3634 }
3635
3636 free_xid(xid);
3637
3638 return mount_setup_tlink(cifs_sb, ses, tcon);
3639
3640error:
3641 mount_put_conns(cifs_sb, xid, server, ses, tcon);
3642 return rc;
3643}
3644#endif
3645
3646/*
3647 * Issue a TREE_CONNECT request.
3648 */
3649int
3650CIFSTCon(const unsigned int xid, struct cifs_ses *ses,
3651 const char *tree, struct cifs_tcon *tcon,
3652 const struct nls_table *nls_codepage)
3653{
3654 struct smb_hdr *smb_buffer;
3655 struct smb_hdr *smb_buffer_response;
3656 TCONX_REQ *pSMB;
3657 TCONX_RSP *pSMBr;
3658 unsigned char *bcc_ptr;
3659 int rc = 0;
3660 int length;
3661 __u16 bytes_left, count;
3662
3663 if (ses == NULL)
3664 return -EIO;
3665
3666 smb_buffer = cifs_buf_get();
3667 if (smb_buffer == NULL)
3668 return -ENOMEM;
3669
3670 smb_buffer_response = smb_buffer;
3671
3672 header_assemble(smb_buffer, SMB_COM_TREE_CONNECT_ANDX,
3673 NULL /*no tid */ , 4 /*wct */ );
3674
3675 smb_buffer->Mid = get_next_mid(ses->server);
3676 smb_buffer->Uid = ses->Suid;
3677 pSMB = (TCONX_REQ *) smb_buffer;
3678 pSMBr = (TCONX_RSP *) smb_buffer_response;
3679
3680 pSMB->AndXCommand = 0xFF;
3681 pSMB->Flags = cpu_to_le16(TCON_EXTENDED_SECINFO);
3682 bcc_ptr = &pSMB->Password[0];
3683 if (tcon->pipe || (ses->server->sec_mode & SECMODE_USER)) {
3684 pSMB->PasswordLength = cpu_to_le16(1); /* minimum */
3685 *bcc_ptr = 0; /* password is null byte */
3686 bcc_ptr++; /* skip password */
3687 /* already aligned so no need to do it below */
3688 } else {
3689 pSMB->PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
3690 /* BB FIXME add code to fail this if NTLMv2 or Kerberos
3691 specified as required (when that support is added to
3692 the vfs in the future) as only NTLM or the much
3693 weaker LANMAN (which we do not send by default) is accepted
3694 by Samba (not sure whether other servers allow
3695 NTLMv2 password here) */
3696#ifdef CONFIG_CIFS_WEAK_PW_HASH
3697 if ((global_secflags & CIFSSEC_MAY_LANMAN) &&
3698 (ses->sectype == LANMAN))
3699 calc_lanman_hash(tcon->password, ses->server->cryptkey,
3700 ses->server->sec_mode &
3701 SECMODE_PW_ENCRYPT ? true : false,
3702 bcc_ptr);
3703 else
3704#endif /* CIFS_WEAK_PW_HASH */
3705 rc = SMBNTencrypt(tcon->password, ses->server->cryptkey,
3706 bcc_ptr, nls_codepage);
3707 if (rc) {
3708 cifs_dbg(FYI, "%s Can't generate NTLM rsp. Error: %d\n",
3709 __func__, rc);
3710 cifs_buf_release(smb_buffer);
3711 return rc;
3712 }
3713
3714 bcc_ptr += CIFS_AUTH_RESP_SIZE;
3715 if (ses->capabilities & CAP_UNICODE) {
3716 /* must align unicode strings */
3717 *bcc_ptr = 0; /* null byte password */
3718 bcc_ptr++;
3719 }
3720 }
3721
3722 if (ses->server->sign)
3723 smb_buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
3724
3725 if (ses->capabilities & CAP_STATUS32) {
3726 smb_buffer->Flags2 |= SMBFLG2_ERR_STATUS;
3727 }
3728 if (ses->capabilities & CAP_DFS) {
3729 smb_buffer->Flags2 |= SMBFLG2_DFS;
3730 }
3731 if (ses->capabilities & CAP_UNICODE) {
3732 smb_buffer->Flags2 |= SMBFLG2_UNICODE;
3733 length =
3734 cifs_strtoUTF16((__le16 *) bcc_ptr, tree,
3735 6 /* max utf8 char length in bytes */ *
3736 (/* server len*/ + 256 /* share len */), nls_codepage);
3737 bcc_ptr += 2 * length; /* convert num 16 bit words to bytes */
3738 bcc_ptr += 2; /* skip trailing null */
3739 } else { /* ASCII */
3740 strcpy(bcc_ptr, tree);
3741 bcc_ptr += strlen(tree) + 1;
3742 }
3743 strcpy(bcc_ptr, "?????");
3744 bcc_ptr += strlen("?????");
3745 bcc_ptr += 1;
3746 count = bcc_ptr - &pSMB->Password[0];
3747 be32_add_cpu(&pSMB->hdr.smb_buf_length, count);
3748 pSMB->ByteCount = cpu_to_le16(count);
3749
3750 rc = SendReceive(xid, ses, smb_buffer, smb_buffer_response, &length,
3751 0);
3752
3753 /* above now done in SendReceive */
3754 if (rc == 0) {
3755 bool is_unicode;
3756
3757 tcon->tidStatus = CifsGood;
3758 tcon->need_reconnect = false;
3759 tcon->tid = smb_buffer_response->Tid;
3760 bcc_ptr = pByteArea(smb_buffer_response);
3761 bytes_left = get_bcc(smb_buffer_response);
3762 length = strnlen(bcc_ptr, bytes_left - 2);
3763 if (smb_buffer->Flags2 & SMBFLG2_UNICODE)
3764 is_unicode = true;
3765 else
3766 is_unicode = false;
3767
3768
3769 /* skip service field (NB: this field is always ASCII) */
3770 if (length == 3) {
3771 if ((bcc_ptr[0] == 'I') && (bcc_ptr[1] == 'P') &&
3772 (bcc_ptr[2] == 'C')) {
3773 cifs_dbg(FYI, "IPC connection\n");
3774 tcon->ipc = true;
3775 tcon->pipe = true;
3776 }
3777 } else if (length == 2) {
3778 if ((bcc_ptr[0] == 'A') && (bcc_ptr[1] == ':')) {
3779 /* the most common case */
3780 cifs_dbg(FYI, "disk share connection\n");
3781 }
3782 }
3783 bcc_ptr += length + 1;
3784 bytes_left -= (length + 1);
3785 strlcpy(tcon->treeName, tree, sizeof(tcon->treeName));
3786
3787 /* mostly informational -- no need to fail on error here */
3788 kfree(tcon->nativeFileSystem);
3789 tcon->nativeFileSystem = cifs_strndup_from_utf16(bcc_ptr,
3790 bytes_left, is_unicode,
3791 nls_codepage);
3792
3793 cifs_dbg(FYI, "nativeFileSystem=%s\n", tcon->nativeFileSystem);
3794
3795 if ((smb_buffer_response->WordCount == 3) ||
3796 (smb_buffer_response->WordCount == 7))
3797 /* field is in same location */
3798 tcon->Flags = le16_to_cpu(pSMBr->OptionalSupport);
3799 else
3800 tcon->Flags = 0;
3801 cifs_dbg(FYI, "Tcon flags: 0x%x\n", tcon->Flags);
3802 }
3803
3804 cifs_buf_release(smb_buffer);
3805 return rc;
3806}
3807
3808static void delayed_free(struct rcu_head *p)
3809{
3810 struct cifs_sb_info *cifs_sb = container_of(p, struct cifs_sb_info, rcu);
3811
3812 unload_nls(cifs_sb->local_nls);
3813 smb3_cleanup_fs_context(cifs_sb->ctx);
3814 kfree(cifs_sb);
3815}
3816
3817void
3818cifs_umount(struct cifs_sb_info *cifs_sb)
3819{
3820 struct rb_root *root = &cifs_sb->tlink_tree;
3821 struct rb_node *node;
3822 struct tcon_link *tlink;
3823
3824 cancel_delayed_work_sync(&cifs_sb->prune_tlinks);
3825
3826 spin_lock(&cifs_sb->tlink_tree_lock);
3827 while ((node = rb_first(root))) {
3828 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
3829 cifs_get_tlink(tlink);
3830 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
3831 rb_erase(node, root);
3832
3833 spin_unlock(&cifs_sb->tlink_tree_lock);
3834 cifs_put_tlink(tlink);
3835 spin_lock(&cifs_sb->tlink_tree_lock);
3836 }
3837 spin_unlock(&cifs_sb->tlink_tree_lock);
3838
3839 kfree(cifs_sb->prepath);
3840#ifdef CONFIG_CIFS_DFS_UPCALL
3841 dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
3842 kfree(cifs_sb->origin_fullpath);
3843#endif
3844 call_rcu(&cifs_sb->rcu, delayed_free);
3845}
3846
3847int
3848cifs_negotiate_protocol(const unsigned int xid, struct cifs_ses *ses)
3849{
3850 int rc = 0;
3851 struct TCP_Server_Info *server = cifs_ses_server(ses);
3852
3853 if (!server->ops->need_neg || !server->ops->negotiate)
3854 return -ENOSYS;
3855
3856 /* only send once per connect */
3857 if (!server->ops->need_neg(server))
3858 return 0;
3859
3860 rc = server->ops->negotiate(xid, ses);
3861 if (rc == 0) {
3862 spin_lock(&GlobalMid_Lock);
3863 if (server->tcpStatus == CifsNeedNegotiate)
3864 server->tcpStatus = CifsGood;
3865 else
3866 rc = -EHOSTDOWN;
3867 spin_unlock(&GlobalMid_Lock);
3868 }
3869
3870 return rc;
3871}
3872
3873int
3874cifs_setup_session(const unsigned int xid, struct cifs_ses *ses,
3875 struct nls_table *nls_info)
3876{
3877 int rc = -ENOSYS;
3878 struct TCP_Server_Info *server = cifs_ses_server(ses);
3879
3880 if (!ses->binding) {
3881 ses->capabilities = server->capabilities;
3882 if (!linuxExtEnabled)
3883 ses->capabilities &= (~server->vals->cap_unix);
3884
3885 if (ses->auth_key.response) {
3886 cifs_dbg(FYI, "Free previous auth_key.response = %p\n",
3887 ses->auth_key.response);
3888 kfree(ses->auth_key.response);
3889 ses->auth_key.response = NULL;
3890 ses->auth_key.len = 0;
3891 }
3892 }
3893
3894 cifs_dbg(FYI, "Security Mode: 0x%x Capabilities: 0x%x TimeAdjust: %d\n",
3895 server->sec_mode, server->capabilities, server->timeAdj);
3896
3897 if (server->ops->sess_setup)
3898 rc = server->ops->sess_setup(xid, ses, nls_info);
3899
3900 if (rc)
3901 cifs_server_dbg(VFS, "Send error in SessSetup = %d\n", rc);
3902
3903 return rc;
3904}
3905
3906static int
3907cifs_set_vol_auth(struct smb3_fs_context *ctx, struct cifs_ses *ses)
3908{
3909 ctx->sectype = ses->sectype;
3910
3911 /* krb5 is special, since we don't need username or pw */
3912 if (ctx->sectype == Kerberos)
3913 return 0;
3914
3915 return cifs_set_cifscreds(ctx, ses);
3916}
3917
3918static struct cifs_tcon *
3919cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
3920{
3921 int rc;
3922 struct cifs_tcon *master_tcon = cifs_sb_master_tcon(cifs_sb);
3923 struct cifs_ses *ses;
3924 struct cifs_tcon *tcon = NULL;
3925 struct smb3_fs_context *ctx;
3926
3927 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
3928 if (ctx == NULL)
3929 return ERR_PTR(-ENOMEM);
3930
3931 ctx->local_nls = cifs_sb->local_nls;
3932 ctx->linux_uid = fsuid;
3933 ctx->cred_uid = fsuid;
3934 ctx->UNC = master_tcon->treeName;
3935 ctx->retry = master_tcon->retry;
3936 ctx->nocase = master_tcon->nocase;
3937 ctx->nohandlecache = master_tcon->nohandlecache;
3938 ctx->local_lease = master_tcon->local_lease;
3939 ctx->no_lease = master_tcon->no_lease;
3940 ctx->resilient = master_tcon->use_resilient;
3941 ctx->persistent = master_tcon->use_persistent;
3942 ctx->handle_timeout = master_tcon->handle_timeout;
3943 ctx->no_linux_ext = !master_tcon->unix_ext;
3944 ctx->linux_ext = master_tcon->posix_extensions;
3945 ctx->sectype = master_tcon->ses->sectype;
3946 ctx->sign = master_tcon->ses->sign;
3947 ctx->seal = master_tcon->seal;
3948 ctx->witness = master_tcon->use_witness;
3949
3950 rc = cifs_set_vol_auth(ctx, master_tcon->ses);
3951 if (rc) {
3952 tcon = ERR_PTR(rc);
3953 goto out;
3954 }
3955
3956 /* get a reference for the same TCP session */
3957 spin_lock(&cifs_tcp_ses_lock);
3958 ++master_tcon->ses->server->srv_count;
3959 spin_unlock(&cifs_tcp_ses_lock);
3960
3961 ses = cifs_get_smb_ses(master_tcon->ses->server, ctx);
3962 if (IS_ERR(ses)) {
3963 tcon = (struct cifs_tcon *)ses;
3964 cifs_put_tcp_session(master_tcon->ses->server, 0);
3965 goto out;
3966 }
3967
3968 tcon = cifs_get_tcon(ses, ctx);
3969 if (IS_ERR(tcon)) {
3970 cifs_put_smb_ses(ses);
3971 goto out;
3972 }
3973
3974 if (cap_unix(ses))
3975 reset_cifs_unix_caps(0, tcon, NULL, ctx);
3976
3977out:
3978 kfree(ctx->username);
3979 kfree_sensitive(ctx->password);
3980 kfree(ctx);
3981
3982 return tcon;
3983}
3984
3985struct cifs_tcon *
3986cifs_sb_master_tcon(struct cifs_sb_info *cifs_sb)
3987{
3988 return tlink_tcon(cifs_sb_master_tlink(cifs_sb));
3989}
3990
3991/* find and return a tlink with given uid */
3992static struct tcon_link *
3993tlink_rb_search(struct rb_root *root, kuid_t uid)
3994{
3995 struct rb_node *node = root->rb_node;
3996 struct tcon_link *tlink;
3997
3998 while (node) {
3999 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
4000
4001 if (uid_gt(tlink->tl_uid, uid))
4002 node = node->rb_left;
4003 else if (uid_lt(tlink->tl_uid, uid))
4004 node = node->rb_right;
4005 else
4006 return tlink;
4007 }
4008 return NULL;
4009}
4010
4011/* insert a tcon_link into the tree */
4012static void
4013tlink_rb_insert(struct rb_root *root, struct tcon_link *new_tlink)
4014{
4015 struct rb_node **new = &(root->rb_node), *parent = NULL;
4016 struct tcon_link *tlink;
4017
4018 while (*new) {
4019 tlink = rb_entry(*new, struct tcon_link, tl_rbnode);
4020 parent = *new;
4021
4022 if (uid_gt(tlink->tl_uid, new_tlink->tl_uid))
4023 new = &((*new)->rb_left);
4024 else
4025 new = &((*new)->rb_right);
4026 }
4027
4028 rb_link_node(&new_tlink->tl_rbnode, parent, new);
4029 rb_insert_color(&new_tlink->tl_rbnode, root);
4030}
4031
4032/*
4033 * Find or construct an appropriate tcon given a cifs_sb and the fsuid of the
4034 * current task.
4035 *
4036 * If the superblock doesn't refer to a multiuser mount, then just return
4037 * the master tcon for the mount.
4038 *
4039 * First, search the rbtree for an existing tcon for this fsuid. If one
4040 * exists, then check to see if it's pending construction. If it is then wait
4041 * for construction to complete. Once it's no longer pending, check to see if
4042 * it failed and either return an error or retry construction, depending on
4043 * the timeout.
4044 *
4045 * If one doesn't exist then insert a new tcon_link struct into the tree and
4046 * try to construct a new one.
4047 */
4048struct tcon_link *
4049cifs_sb_tlink(struct cifs_sb_info *cifs_sb)
4050{
4051 int ret;
4052 kuid_t fsuid = current_fsuid();
4053 struct tcon_link *tlink, *newtlink;
4054
4055 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MULTIUSER))
4056 return cifs_get_tlink(cifs_sb_master_tlink(cifs_sb));
4057
4058 spin_lock(&cifs_sb->tlink_tree_lock);
4059 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4060 if (tlink)
4061 cifs_get_tlink(tlink);
4062 spin_unlock(&cifs_sb->tlink_tree_lock);
4063
4064 if (tlink == NULL) {
4065 newtlink = kzalloc(sizeof(*tlink), GFP_KERNEL);
4066 if (newtlink == NULL)
4067 return ERR_PTR(-ENOMEM);
4068 newtlink->tl_uid = fsuid;
4069 newtlink->tl_tcon = ERR_PTR(-EACCES);
4070 set_bit(TCON_LINK_PENDING, &newtlink->tl_flags);
4071 set_bit(TCON_LINK_IN_TREE, &newtlink->tl_flags);
4072 cifs_get_tlink(newtlink);
4073
4074 spin_lock(&cifs_sb->tlink_tree_lock);
4075 /* was one inserted after previous search? */
4076 tlink = tlink_rb_search(&cifs_sb->tlink_tree, fsuid);
4077 if (tlink) {
4078 cifs_get_tlink(tlink);
4079 spin_unlock(&cifs_sb->tlink_tree_lock);
4080 kfree(newtlink);
4081 goto wait_for_construction;
4082 }
4083 tlink = newtlink;
4084 tlink_rb_insert(&cifs_sb->tlink_tree, tlink);
4085 spin_unlock(&cifs_sb->tlink_tree_lock);
4086 } else {
4087wait_for_construction:
4088 ret = wait_on_bit(&tlink->tl_flags, TCON_LINK_PENDING,
4089 TASK_INTERRUPTIBLE);
4090 if (ret) {
4091 cifs_put_tlink(tlink);
4092 return ERR_PTR(-ERESTARTSYS);
4093 }
4094
4095 /* if it's good, return it */
4096 if (!IS_ERR(tlink->tl_tcon))
4097 return tlink;
4098
4099 /* return error if we tried this already recently */
4100 if (time_before(jiffies, tlink->tl_time + TLINK_ERROR_EXPIRE)) {
4101 cifs_put_tlink(tlink);
4102 return ERR_PTR(-EACCES);
4103 }
4104
4105 if (test_and_set_bit(TCON_LINK_PENDING, &tlink->tl_flags))
4106 goto wait_for_construction;
4107 }
4108
4109 tlink->tl_tcon = cifs_construct_tcon(cifs_sb, fsuid);
4110 clear_bit(TCON_LINK_PENDING, &tlink->tl_flags);
4111 wake_up_bit(&tlink->tl_flags, TCON_LINK_PENDING);
4112
4113 if (IS_ERR(tlink->tl_tcon)) {
4114 cifs_put_tlink(tlink);
4115 return ERR_PTR(-EACCES);
4116 }
4117
4118 return tlink;
4119}
4120
4121/*
4122 * periodic workqueue job that scans tcon_tree for a superblock and closes
4123 * out tcons.
4124 */
4125static void
4126cifs_prune_tlinks(struct work_struct *work)
4127{
4128 struct cifs_sb_info *cifs_sb = container_of(work, struct cifs_sb_info,
4129 prune_tlinks.work);
4130 struct rb_root *root = &cifs_sb->tlink_tree;
4131 struct rb_node *node;
4132 struct rb_node *tmp;
4133 struct tcon_link *tlink;
4134
4135 /*
4136 * Because we drop the spinlock in the loop in order to put the tlink
4137 * it's not guarded against removal of links from the tree. The only
4138 * places that remove entries from the tree are this function and
4139 * umounts. Because this function is non-reentrant and is canceled
4140 * before umount can proceed, this is safe.
4141 */
4142 spin_lock(&cifs_sb->tlink_tree_lock);
4143 node = rb_first(root);
4144 while (node != NULL) {
4145 tmp = node;
4146 node = rb_next(tmp);
4147 tlink = rb_entry(tmp, struct tcon_link, tl_rbnode);
4148
4149 if (test_bit(TCON_LINK_MASTER, &tlink->tl_flags) ||
4150 atomic_read(&tlink->tl_count) != 0 ||
4151 time_after(tlink->tl_time + TLINK_IDLE_EXPIRE, jiffies))
4152 continue;
4153
4154 cifs_get_tlink(tlink);
4155 clear_bit(TCON_LINK_IN_TREE, &tlink->tl_flags);
4156 rb_erase(tmp, root);
4157
4158 spin_unlock(&cifs_sb->tlink_tree_lock);
4159 cifs_put_tlink(tlink);
4160 spin_lock(&cifs_sb->tlink_tree_lock);
4161 }
4162 spin_unlock(&cifs_sb->tlink_tree_lock);
4163
4164 queue_delayed_work(cifsiod_wq, &cifs_sb->prune_tlinks,
4165 TLINK_IDLE_EXPIRE);
4166}
4167
4168#ifdef CONFIG_CIFS_DFS_UPCALL
4169int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4170{
4171 int rc;
4172 struct TCP_Server_Info *server = tcon->ses->server;
4173 const struct smb_version_operations *ops = server->ops;
4174 struct dfs_cache_tgt_list tl;
4175 struct dfs_cache_tgt_iterator *it = NULL;
4176 char *tree;
4177 const char *tcp_host;
4178 size_t tcp_host_len;
4179 const char *dfs_host;
4180 size_t dfs_host_len;
4181 char *share = NULL, *prefix = NULL;
4182 struct dfs_info3_param ref = {0};
4183 bool isroot;
4184
4185 tree = kzalloc(MAX_TREE_SIZE, GFP_KERNEL);
4186 if (!tree)
4187 return -ENOMEM;
4188
4189 /* If it is not dfs or there was no cached dfs referral, then reconnect to same share */
4190 if (!tcon->dfs_path || dfs_cache_noreq_find(tcon->dfs_path + 1, &ref, &tl)) {
4191 if (tcon->ipc) {
4192 scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", server->hostname);
4193 rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4194 } else {
4195 rc = ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
4196 }
4197 goto out;
4198 }
4199
4200 isroot = ref.server_type == DFS_TYPE_ROOT;
4201 free_dfs_info_param(&ref);
4202
4203 extract_unc_hostname(server->hostname, &tcp_host, &tcp_host_len);
4204
4205 for (it = dfs_cache_get_tgt_iterator(&tl); it; it = dfs_cache_get_next_tgt(&tl, it)) {
4206 bool target_match;
4207
4208 kfree(share);
4209 kfree(prefix);
4210 share = NULL;
4211 prefix = NULL;
4212
4213 rc = dfs_cache_get_tgt_share(tcon->dfs_path + 1, it, &share, &prefix);
4214 if (rc) {
4215 cifs_dbg(VFS, "%s: failed to parse target share %d\n",
4216 __func__, rc);
4217 continue;
4218 }
4219
4220 extract_unc_hostname(share, &dfs_host, &dfs_host_len);
4221
4222 if (dfs_host_len != tcp_host_len
4223 || strncasecmp(dfs_host, tcp_host, dfs_host_len) != 0) {
4224 cifs_dbg(FYI, "%s: %.*s doesn't match %.*s\n", __func__, (int)dfs_host_len,
4225 dfs_host, (int)tcp_host_len, tcp_host);
4226
4227 rc = match_target_ip(server, dfs_host, dfs_host_len, &target_match);
4228 if (rc) {
4229 cifs_dbg(VFS, "%s: failed to match target ip: %d\n", __func__, rc);
4230 break;
4231 }
4232
4233 if (!target_match) {
4234 cifs_dbg(FYI, "%s: skipping target\n", __func__);
4235 continue;
4236 }
4237 }
4238
4239 if (tcon->ipc) {
4240 scnprintf(tree, MAX_TREE_SIZE, "\\\\%s\\IPC$", share);
4241 rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4242 } else {
4243 scnprintf(tree, MAX_TREE_SIZE, "\\%s", share);
4244 rc = ops->tree_connect(xid, tcon->ses, tree, tcon, nlsc);
4245 /* Only handle prefix paths of DFS link targets */
4246 if (!rc && !isroot) {
4247 rc = update_super_prepath(tcon, prefix);
4248 break;
4249 }
4250 }
4251 if (rc == -EREMOTE)
4252 break;
4253 }
4254
4255 kfree(share);
4256 kfree(prefix);
4257
4258 if (!rc) {
4259 if (it)
4260 rc = dfs_cache_noreq_update_tgthint(tcon->dfs_path + 1, it);
4261 else
4262 rc = -ENOENT;
4263 }
4264 dfs_cache_free_tgts(&tl);
4265out:
4266 kfree(tree);
4267 return rc;
4268}
4269#else
4270int cifs_tree_connect(const unsigned int xid, struct cifs_tcon *tcon, const struct nls_table *nlsc)
4271{
4272 const struct smb_version_operations *ops = tcon->ses->server->ops;
4273
4274 return ops->tree_connect(xid, tcon->ses, tcon->treeName, tcon, nlsc);
4275}
4276#endif