1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2008
5 * Author(s): Steve French (sfrench@us.ibm.com)
6 *
7 */
8
9 #include <linux/slab.h>
10 #include <linux/ctype.h>
11 #include <linux/mempool.h>
12 #include <linux/vmalloc.h>
13 #include "cifsglob.h"
14 #include "cifsproto.h"
15 #include "cifs_debug.h"
16 #include "smberr.h"
17 #include "nterr.h"
18 #include "cifs_unicode.h"
19 #include "smb2pdu.h"
20 #include "smb2proto.h"
21 #include "smb1proto.h"
22 #include "cifsfs.h"
23 #ifdef CONFIG_CIFS_DFS_UPCALL
24 #include "dns_resolve.h"
25 #include "dfs_cache.h"
26 #include "dfs.h"
27 #endif
28 #include "fs_context.h"
29 #include "cached_dir.h"
30
31 struct tcon_list {
32 struct list_head entry;
33 struct cifs_tcon *tcon;
34 };
35
36 /* The xid serves as a useful identifier for each incoming vfs request,
37 in a similar way to the mid which is useful to track each sent smb,
38 and CurrentXid can also provide a running counter (although it
39 will eventually wrap past zero) of the total vfs operations handled
40 since the cifs fs was mounted */
41
42 unsigned int
_get_xid(void)43 _get_xid(void)
44 {
45 unsigned int xid;
46
47 spin_lock(&GlobalMid_Lock);
48 GlobalTotalActiveXid++;
49
50 /* keep high water mark for number of simultaneous ops in filesystem */
51 if (GlobalTotalActiveXid > GlobalMaxActiveXid)
52 GlobalMaxActiveXid = GlobalTotalActiveXid;
53 if (GlobalTotalActiveXid > 65000)
54 cifs_dbg(FYI, "warning: more than 65000 requests active\n");
55 xid = GlobalCurrentXid++;
56 spin_unlock(&GlobalMid_Lock);
57 return xid;
58 }
59
60 void
_free_xid(unsigned int xid)61 _free_xid(unsigned int xid)
62 {
63 spin_lock(&GlobalMid_Lock);
64 /* if (GlobalTotalActiveXid == 0)
65 BUG(); */
66 GlobalTotalActiveXid--;
67 spin_unlock(&GlobalMid_Lock);
68 }
69
70 struct cifs_ses *
sesInfoAlloc(void)71 sesInfoAlloc(void)
72 {
73 struct cifs_ses *ret_buf;
74
75 ret_buf = kzalloc_obj(struct cifs_ses);
76 if (ret_buf) {
77 atomic_inc(&sesInfoAllocCount);
78 spin_lock_init(&ret_buf->ses_lock);
79 ret_buf->ses_status = SES_NEW;
80 ++ret_buf->ses_count;
81 INIT_LIST_HEAD(&ret_buf->smb_ses_list);
82 INIT_LIST_HEAD(&ret_buf->tcon_list);
83 mutex_init(&ret_buf->session_mutex);
84 spin_lock_init(&ret_buf->iface_lock);
85 INIT_LIST_HEAD(&ret_buf->iface_list);
86 spin_lock_init(&ret_buf->chan_lock);
87 }
88 return ret_buf;
89 }
90
91 void
sesInfoFree(struct cifs_ses * buf_to_free)92 sesInfoFree(struct cifs_ses *buf_to_free)
93 {
94 struct cifs_server_iface *iface = NULL, *niface = NULL;
95
96 if (buf_to_free == NULL) {
97 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n");
98 return;
99 }
100
101 unload_nls(buf_to_free->local_nls);
102 atomic_dec(&sesInfoAllocCount);
103 kfree(buf_to_free->serverOS);
104 kfree(buf_to_free->serverDomain);
105 kfree(buf_to_free->serverNOS);
106 kfree_sensitive(buf_to_free->password);
107 kfree_sensitive(buf_to_free->password2);
108 kfree(buf_to_free->user_name);
109 kfree(buf_to_free->domainName);
110 kfree(buf_to_free->dns_dom);
111 kfree_sensitive(buf_to_free->auth_key.response);
112 spin_lock(&buf_to_free->iface_lock);
113 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list,
114 iface_head)
115 kref_put(&iface->refcount, release_iface);
116 spin_unlock(&buf_to_free->iface_lock);
117 kfree_sensitive(buf_to_free);
118 }
119
120 struct cifs_tcon *
tcon_info_alloc(bool dir_leases_enabled,enum smb3_tcon_ref_trace trace)121 tcon_info_alloc(bool dir_leases_enabled, enum smb3_tcon_ref_trace trace)
122 {
123 struct cifs_tcon *ret_buf;
124 static atomic_t tcon_debug_id;
125
126 ret_buf = kzalloc_obj(*ret_buf);
127 if (!ret_buf)
128 return NULL;
129
130 if (dir_leases_enabled == true) {
131 ret_buf->cfids = init_cached_dirs();
132 if (!ret_buf->cfids) {
133 kfree(ret_buf);
134 return NULL;
135 }
136 }
137 /* else ret_buf->cfids is already set to NULL above */
138
139 atomic_inc(&tconInfoAllocCount);
140 ret_buf->status = TID_NEW;
141 ret_buf->debug_id = atomic_inc_return(&tcon_debug_id);
142 ret_buf->tc_count = 1;
143 spin_lock_init(&ret_buf->tc_lock);
144 INIT_LIST_HEAD(&ret_buf->openFileList);
145 INIT_LIST_HEAD(&ret_buf->tcon_list);
146 INIT_LIST_HEAD(&ret_buf->cifs_sb_list);
147 spin_lock_init(&ret_buf->open_file_lock);
148 spin_lock_init(&ret_buf->stat_lock);
149 spin_lock_init(&ret_buf->sb_list_lock);
150 atomic_set(&ret_buf->num_local_opens, 0);
151 atomic_set(&ret_buf->num_remote_opens, 0);
152 ret_buf->stats_from_time = ktime_get_real_seconds();
153 #ifdef CONFIG_CIFS_FSCACHE
154 mutex_init(&ret_buf->fscache_lock);
155 #endif
156 trace_smb3_tcon_ref(ret_buf->debug_id, ret_buf->tc_count, trace);
157 #ifdef CONFIG_CIFS_DFS_UPCALL
158 INIT_LIST_HEAD(&ret_buf->dfs_ses_list);
159 #endif
160 INIT_LIST_HEAD(&ret_buf->pending_opens);
161 INIT_DELAYED_WORK(&ret_buf->query_interfaces,
162 smb2_query_server_interfaces);
163 #ifdef CONFIG_CIFS_DFS_UPCALL
164 INIT_DELAYED_WORK(&ret_buf->dfs_cache_work, dfs_cache_refresh);
165 #endif
166
167 return ret_buf;
168 }
169
170 void
tconInfoFree(struct cifs_tcon * tcon,enum smb3_tcon_ref_trace trace)171 tconInfoFree(struct cifs_tcon *tcon, enum smb3_tcon_ref_trace trace)
172 {
173 if (tcon == NULL) {
174 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");
175 return;
176 }
177 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, trace);
178 free_cached_dirs(tcon->cfids);
179 atomic_dec(&tconInfoAllocCount);
180 kfree(tcon->nativeFileSystem);
181 kfree_sensitive(tcon->password);
182 kfree(tcon->origin_fullpath);
183 kfree(tcon);
184 }
185
186 void *
cifs_buf_get(void)187 cifs_buf_get(void)
188 {
189 void *ret_buf = NULL;
190 /*
191 * SMB2 header is bigger than CIFS one - no problems to clean some
192 * more bytes for CIFS.
193 */
194 size_t buf_size = sizeof(struct smb2_hdr);
195
196 /*
197 * We could use negotiated size instead of max_msgsize -
198 * but it may be more efficient to always alloc same size
199 * albeit slightly larger than necessary and maxbuffersize
200 * defaults to this and can not be bigger.
201 */
202 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
203
204 /* clear the first few header bytes */
205 /* for most paths, more is cleared in header_assemble */
206 memset(ret_buf, 0, buf_size + 3);
207 atomic_inc(&buf_alloc_count);
208 #ifdef CONFIG_CIFS_STATS2
209 atomic_inc(&total_buf_alloc_count);
210 #endif /* CONFIG_CIFS_STATS2 */
211
212 return ret_buf;
213 }
214
215 void
cifs_buf_release(void * buf_to_free)216 cifs_buf_release(void *buf_to_free)
217 {
218 if (buf_to_free == NULL) {
219 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/
220 return;
221 }
222 mempool_free(buf_to_free, cifs_req_poolp);
223
224 atomic_dec(&buf_alloc_count);
225 return;
226 }
227
228 void *
cifs_small_buf_get(void)229 cifs_small_buf_get(void)
230 {
231 void *ret_buf = NULL;
232
233 /* We could use negotiated size instead of max_msgsize -
234 but it may be more efficient to always alloc same size
235 albeit slightly larger than necessary and maxbuffersize
236 defaults to this and can not be bigger */
237 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
238 /* No need to clear memory here, cleared in header assemble */
239 atomic_inc(&small_buf_alloc_count);
240 #ifdef CONFIG_CIFS_STATS2
241 atomic_inc(&total_small_buf_alloc_count);
242 #endif /* CONFIG_CIFS_STATS2 */
243
244 return ret_buf;
245 }
246
247 void
cifs_small_buf_release(void * buf_to_free)248 cifs_small_buf_release(void *buf_to_free)
249 {
250
251 if (buf_to_free == NULL) {
252 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n");
253 return;
254 }
255 mempool_free(buf_to_free, cifs_sm_req_poolp);
256
257 atomic_dec(&small_buf_alloc_count);
258 return;
259 }
260
261 void
free_rsp_buf(int resp_buftype,void * rsp)262 free_rsp_buf(int resp_buftype, void *rsp)
263 {
264 if (resp_buftype == CIFS_SMALL_BUFFER)
265 cifs_small_buf_release(rsp);
266 else if (resp_buftype == CIFS_LARGE_BUFFER)
267 cifs_buf_release(rsp);
268 }
269
270 void
dump_smb(void * buf,int smb_buf_length)271 dump_smb(void *buf, int smb_buf_length)
272 {
273 if (traceSMB == 0)
274 return;
275
276 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf,
277 smb_buf_length, true);
278 }
279
280 void
cifs_autodisable_serverino(struct cifs_sb_info * cifs_sb,const char * reason,int rc)281 cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb, const char *reason, int rc)
282 {
283 unsigned int sbflags = cifs_sb_flags(cifs_sb);
284
285 if (sbflags & CIFS_MOUNT_SERVER_INUM) {
286 struct cifs_tcon *tcon = NULL;
287
288 if (cifs_sb->master_tlink)
289 tcon = cifs_sb_master_tcon(cifs_sb);
290
291 atomic_andnot(CIFS_MOUNT_SERVER_INUM, &cifs_sb->mnt_cifs_flags);
292 cifs_sb->mnt_cifs_serverino_autodisabled = true;
293 if (rc)
294 cifs_dbg(VFS, "%s: %d\n", reason, rc);
295 else
296 cifs_dbg(VFS, "%s\n", reason);
297 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n",
298 tcon ? tcon->tree_name : "new server");
299 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n");
300 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n");
301
302 }
303 }
304
cifs_set_oplock_level(struct cifsInodeInfo * cinode,__u32 oplock)305 void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
306 {
307 oplock &= 0xF;
308
309 if (oplock == OPLOCK_EXCLUSIVE) {
310 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;
311 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
312 &cinode->netfs.inode);
313 } else if (oplock == OPLOCK_READ) {
314 cinode->oplock = CIFS_CACHE_READ_FLG;
315 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
316 &cinode->netfs.inode);
317 } else
318 cinode->oplock = 0;
319 }
320
321 /*
322 * We wait for oplock breaks to be processed before we attempt to perform
323 * writes.
324 */
cifs_get_writer(struct cifsInodeInfo * cinode)325 int cifs_get_writer(struct cifsInodeInfo *cinode)
326 {
327 int rc;
328
329 start:
330 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,
331 TASK_KILLABLE);
332 if (rc)
333 return rc;
334
335 spin_lock(&cinode->writers_lock);
336 if (!cinode->writers)
337 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
338 cinode->writers++;
339 /* Check to see if we have started servicing an oplock break */
340 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {
341 cinode->writers--;
342 if (cinode->writers == 0) {
343 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
344 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
345 }
346 spin_unlock(&cinode->writers_lock);
347 goto start;
348 }
349 spin_unlock(&cinode->writers_lock);
350 return 0;
351 }
352
cifs_put_writer(struct cifsInodeInfo * cinode)353 void cifs_put_writer(struct cifsInodeInfo *cinode)
354 {
355 spin_lock(&cinode->writers_lock);
356 cinode->writers--;
357 if (cinode->writers == 0) {
358 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
359 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
360 }
361 spin_unlock(&cinode->writers_lock);
362 }
363
364 /**
365 * cifs_queue_oplock_break - queue the oplock break handler for cfile
366 * @cfile: The file to break the oplock on
367 *
368 * This function is called from the demultiplex thread when it
369 * receives an oplock break for @cfile.
370 *
371 * Assumes the tcon->open_file_lock is held.
372 * Assumes cfile->file_info_lock is NOT held.
373 */
cifs_queue_oplock_break(struct cifsFileInfo * cfile)374 void cifs_queue_oplock_break(struct cifsFileInfo *cfile)
375 {
376 /*
377 * Bump the handle refcount now while we hold the
378 * open_file_lock to enforce the validity of it for the oplock
379 * break handler. The matching put is done at the end of the
380 * handler.
381 */
382 cifsFileInfo_get(cfile);
383
384 queue_work(cifsoplockd_wq, &cfile->oplock_break);
385 }
386
cifs_done_oplock_break(struct cifsInodeInfo * cinode)387 void cifs_done_oplock_break(struct cifsInodeInfo *cinode)
388 {
389 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
390 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);
391 }
392
393 bool
backup_cred(struct cifs_sb_info * cifs_sb)394 backup_cred(struct cifs_sb_info *cifs_sb)
395 {
396 unsigned int sbflags = cifs_sb_flags(cifs_sb);
397
398 if (sbflags & CIFS_MOUNT_CIFS_BACKUPUID) {
399 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid()))
400 return true;
401 }
402 if (sbflags & CIFS_MOUNT_CIFS_BACKUPGID) {
403 if (in_group_p(cifs_sb->ctx->backupgid))
404 return true;
405 }
406
407 return false;
408 }
409
410 void
cifs_del_pending_open(struct cifs_pending_open * open)411 cifs_del_pending_open(struct cifs_pending_open *open)
412 {
413 spin_lock(&tlink_tcon(open->tlink)->open_file_lock);
414 list_del(&open->olist);
415 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
416 }
417
418 void
cifs_add_pending_open_locked(struct cifs_fid * fid,struct tcon_link * tlink,struct cifs_pending_open * open)419 cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
420 struct cifs_pending_open *open)
421 {
422 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
423 open->oplock = CIFS_OPLOCK_NO_CHANGE;
424 open->tlink = tlink;
425 fid->pending_open = open;
426 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);
427 }
428
429 void
cifs_add_pending_open(struct cifs_fid * fid,struct tcon_link * tlink,struct cifs_pending_open * open)430 cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,
431 struct cifs_pending_open *open)
432 {
433 spin_lock(&tlink_tcon(tlink)->open_file_lock);
434 cifs_add_pending_open_locked(fid, tlink, open);
435 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
436 }
437
438 /*
439 * Critical section which runs after acquiring deferred_lock.
440 * As there is no reference count on cifs_deferred_close, pdclose
441 * should not be used outside deferred_lock.
442 */
443 bool
cifs_is_deferred_close(struct cifsFileInfo * cfile,struct cifs_deferred_close ** pdclose)444 cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose)
445 {
446 struct cifs_deferred_close *dclose;
447
448 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) {
449 if ((dclose->netfid == cfile->fid.netfid) &&
450 (dclose->persistent_fid == cfile->fid.persistent_fid) &&
451 (dclose->volatile_fid == cfile->fid.volatile_fid)) {
452 *pdclose = dclose;
453 return true;
454 }
455 }
456 return false;
457 }
458
459 /*
460 * Critical section which runs after acquiring deferred_lock.
461 */
462 void
cifs_add_deferred_close(struct cifsFileInfo * cfile,struct cifs_deferred_close * dclose)463 cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose)
464 {
465 bool is_deferred = false;
466 struct cifs_deferred_close *pdclose;
467
468 is_deferred = cifs_is_deferred_close(cfile, &pdclose);
469 if (is_deferred) {
470 kfree(dclose);
471 return;
472 }
473
474 dclose->tlink = cfile->tlink;
475 dclose->netfid = cfile->fid.netfid;
476 dclose->persistent_fid = cfile->fid.persistent_fid;
477 dclose->volatile_fid = cfile->fid.volatile_fid;
478 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes);
479 }
480
481 /*
482 * Critical section which runs after acquiring deferred_lock.
483 */
484 void
cifs_del_deferred_close(struct cifsFileInfo * cfile)485 cifs_del_deferred_close(struct cifsFileInfo *cfile)
486 {
487 bool is_deferred = false;
488 struct cifs_deferred_close *dclose;
489
490 is_deferred = cifs_is_deferred_close(cfile, &dclose);
491 if (!is_deferred)
492 return;
493 list_del(&dclose->dlist);
494 kfree(dclose);
495 }
496
497 void
cifs_close_deferred_file(struct cifsInodeInfo * cifs_inode)498 cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode)
499 {
500 struct cifsFileInfo *cfile = NULL, *failed_cfile = NULL;
501 struct file_list *tmp_list, *tmp_next_list;
502 LIST_HEAD(file_head);
503
504 if (cifs_inode == NULL)
505 return;
506
507 spin_lock(&cifs_inode->open_file_lock);
508 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) {
509 if (delayed_work_pending(&cfile->deferred)) {
510 if (cancel_delayed_work(&cfile->deferred)) {
511 spin_lock(&cifs_inode->deferred_lock);
512 cifs_del_deferred_close(cfile);
513 spin_unlock(&cifs_inode->deferred_lock);
514
515 tmp_list = kmalloc_obj(struct file_list,
516 GFP_ATOMIC);
517 if (tmp_list == NULL) {
518 failed_cfile = cfile;
519 break;
520 }
521 tmp_list->cfile = cfile;
522 list_add_tail(&tmp_list->list, &file_head);
523 }
524 }
525 }
526 spin_unlock(&cifs_inode->open_file_lock);
527
528 if (failed_cfile)
529 _cifsFileInfo_put(failed_cfile, false, false);
530
531 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
532 _cifsFileInfo_put(tmp_list->cfile, false, false);
533 list_del(&tmp_list->list);
534 kfree(tmp_list);
535 }
536 }
537
538 void
cifs_close_all_deferred_files(struct cifs_tcon * tcon)539 cifs_close_all_deferred_files(struct cifs_tcon *tcon)
540 {
541 struct cifsFileInfo *cfile, *failed_cfile = NULL;
542 struct file_list *tmp_list, *tmp_next_list;
543 LIST_HEAD(file_head);
544
545 spin_lock(&tcon->open_file_lock);
546 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
547 if (delayed_work_pending(&cfile->deferred)) {
548 if (cancel_delayed_work(&cfile->deferred)) {
549 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
550 cifs_del_deferred_close(cfile);
551 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
552
553 tmp_list = kmalloc_obj(struct file_list,
554 GFP_ATOMIC);
555 if (tmp_list == NULL) {
556 failed_cfile = cfile;
557 break;
558 }
559 tmp_list->cfile = cfile;
560 list_add_tail(&tmp_list->list, &file_head);
561 }
562 }
563 }
564 spin_unlock(&tcon->open_file_lock);
565
566 if (failed_cfile)
567 _cifsFileInfo_put(failed_cfile, true, false);
568
569 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
570 _cifsFileInfo_put(tmp_list->cfile, true, false);
571 list_del(&tmp_list->list);
572 kfree(tmp_list);
573 }
574 }
575
cifs_close_all_deferred_files_sb(struct cifs_sb_info * cifs_sb)576 void cifs_close_all_deferred_files_sb(struct cifs_sb_info *cifs_sb)
577 {
578 struct rb_root *root = &cifs_sb->tlink_tree;
579 struct rb_node *node;
580 struct cifs_tcon *tcon;
581 struct tcon_link *tlink;
582 struct tcon_list *tmp_list, *q;
583 LIST_HEAD(tcon_head);
584
585 spin_lock(&cifs_sb->tlink_tree_lock);
586 for (node = rb_first(root); node; node = rb_next(node)) {
587 tlink = rb_entry(node, struct tcon_link, tl_rbnode);
588 tcon = tlink_tcon(tlink);
589 if (IS_ERR(tcon))
590 continue;
591 tmp_list = kmalloc_obj(struct tcon_list, GFP_ATOMIC);
592 if (tmp_list == NULL)
593 break;
594 tmp_list->tcon = tcon;
595 /* Take a reference on tcon to prevent it from being freed */
596 spin_lock(&tcon->tc_lock);
597 ++tcon->tc_count;
598 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count,
599 netfs_trace_tcon_ref_get_close_defer_files);
600 spin_unlock(&tcon->tc_lock);
601 list_add_tail(&tmp_list->entry, &tcon_head);
602 }
603 spin_unlock(&cifs_sb->tlink_tree_lock);
604
605 list_for_each_entry_safe(tmp_list, q, &tcon_head, entry) {
606 cifs_close_all_deferred_files(tmp_list->tcon);
607 list_del(&tmp_list->entry);
608 cifs_put_tcon(tmp_list->tcon, netfs_trace_tcon_ref_put_close_defer_files);
609 kfree(tmp_list);
610 }
611 }
612
cifs_close_deferred_file_under_dentry(struct cifs_tcon * tcon,struct dentry * dentry)613 void cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon,
614 struct dentry *dentry)
615 {
616 struct file_list *tmp_list, *tmp_next_list;
617 struct cifsFileInfo *cfile, *failed_cfile = NULL;
618 LIST_HEAD(file_head);
619
620 spin_lock(&tcon->open_file_lock);
621 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
622 if ((cfile->dentry == dentry) &&
623 delayed_work_pending(&cfile->deferred) &&
624 cancel_delayed_work(&cfile->deferred)) {
625 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
626 cifs_del_deferred_close(cfile);
627 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock);
628
629 tmp_list = kmalloc_obj(struct file_list, GFP_ATOMIC);
630 if (tmp_list == NULL) {
631 failed_cfile = cfile;
632 break;
633 }
634 tmp_list->cfile = cfile;
635 list_add_tail(&tmp_list->list, &file_head);
636 }
637 }
638 spin_unlock(&tcon->open_file_lock);
639
640 if (failed_cfile)
641 _cifsFileInfo_put(failed_cfile, true, false);
642
643 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
644 _cifsFileInfo_put(tmp_list->cfile, true, false);
645 list_del(&tmp_list->list);
646 kfree(tmp_list);
647 }
648 }
649
650 /*
651 * If a dentry has been deleted, all corresponding open handles should know that
652 * so that we do not defer close them.
653 */
cifs_mark_open_handles_for_deleted_file(struct inode * inode,const char * path)654 void cifs_mark_open_handles_for_deleted_file(struct inode *inode,
655 const char *path)
656 {
657 struct cifsFileInfo *cfile;
658 void *page;
659 const char *full_path;
660 struct cifsInodeInfo *cinode = CIFS_I(inode);
661
662 page = alloc_dentry_path();
663 spin_lock(&cinode->open_file_lock);
664
665 /*
666 * note: we need to construct path from dentry and compare only if the
667 * inode has any hardlinks. When number of hardlinks is 1, we can just
668 * mark all open handles since they are going to be from the same file.
669 */
670 if (inode->i_nlink > 1) {
671 list_for_each_entry(cfile, &cinode->openFileList, flist) {
672 full_path = build_path_from_dentry(cfile->dentry, page);
673 if (!IS_ERR(full_path) && strcmp(full_path, path) == 0)
674 cfile->status_file_deleted = true;
675 }
676 } else {
677 list_for_each_entry(cfile, &cinode->openFileList, flist)
678 cfile->status_file_deleted = true;
679 }
680 spin_unlock(&cinode->open_file_lock);
681 free_dentry_path(page);
682 }
683
684 /* parses DFS referral V3 structure
685 * caller is responsible for freeing target_nodes
686 * returns:
687 * - on success - 0
688 * - on failure - errno
689 */
690 int
parse_dfs_referrals(struct get_dfs_referral_rsp * rsp,u32 rsp_size,unsigned int * num_of_nodes,struct dfs_info3_param ** target_nodes,const struct nls_table * nls_codepage,int remap,const char * searchName,bool is_unicode)691 parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size,
692 unsigned int *num_of_nodes,
693 struct dfs_info3_param **target_nodes,
694 const struct nls_table *nls_codepage, int remap,
695 const char *searchName, bool is_unicode)
696 {
697 int i, rc = 0;
698 char *data_end;
699 struct dfs_referral_level_3 *ref;
700 unsigned int path_consumed;
701 size_t search_name_len;
702
703 if (rsp_size < sizeof(*rsp)) {
704 cifs_dbg(VFS | ONCE,
705 "%s: header is malformed (size is %u, must be %zu)\n",
706 __func__, rsp_size, sizeof(*rsp));
707 rc = -EINVAL;
708 goto parse_DFS_referrals_exit;
709 }
710
711 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals);
712
713 if (*num_of_nodes < 1) {
714 cifs_dbg(VFS | ONCE, "%s: [path=%s] num_referrals must be at least > 0, but we got %d\n",
715 __func__, searchName, *num_of_nodes);
716 rc = -ENOENT;
717 goto parse_DFS_referrals_exit;
718 }
719
720 if (sizeof(*rsp) + *num_of_nodes * sizeof(REFERRAL3) > rsp_size) {
721 cifs_dbg(VFS | ONCE,
722 "%s: malformed buffer (size is %u, must be at least %zu)\n",
723 __func__, rsp_size,
724 sizeof(*rsp) + *num_of_nodes * sizeof(REFERRAL3));
725 rc = -EINVAL;
726 goto parse_DFS_referrals_exit;
727 }
728
729 ref = (struct dfs_referral_level_3 *) &(rsp->referrals);
730 if (ref->VersionNumber != cpu_to_le16(3)) {
731 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n",
732 le16_to_cpu(ref->VersionNumber));
733 rc = -EINVAL;
734 goto parse_DFS_referrals_exit;
735 }
736
737 /* get the upper boundary of the resp buffer */
738 data_end = (char *)rsp + rsp_size;
739
740 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n",
741 *num_of_nodes, le32_to_cpu(rsp->DFSFlags));
742
743 *target_nodes = kzalloc_objs(struct dfs_info3_param, *num_of_nodes);
744 if (*target_nodes == NULL) {
745 rc = -ENOMEM;
746 goto parse_DFS_referrals_exit;
747 }
748 search_name_len = strlen(searchName);
749
750 /* collect necessary data from referrals */
751 for (i = 0; i < *num_of_nodes; i++) {
752 char *temp;
753 int max_len;
754 struct dfs_info3_param *node = (*target_nodes)+i;
755
756 node->flags = le32_to_cpu(rsp->DFSFlags);
757 path_consumed = le16_to_cpu(rsp->PathConsumed);
758 if (is_unicode) {
759 size_t search_name_utf16_len = search_name_len * 2 + 2;
760 __le16 *tmp;
761
762 if (path_consumed > search_name_utf16_len) {
763 rc = -EINVAL;
764 goto parse_DFS_referrals_exit;
765 }
766
767 tmp = kmalloc(search_name_utf16_len, GFP_KERNEL);
768 if (!tmp) {
769 rc = -ENOMEM;
770 goto parse_DFS_referrals_exit;
771 }
772 cifsConvertToUTF16((__le16 *)tmp, searchName,
773 PATH_MAX, nls_codepage, remap);
774 node->path_consumed = cifs_utf16_bytes(tmp, path_consumed,
775 nls_codepage);
776 kfree(tmp);
777 } else {
778 if (path_consumed > search_name_len) {
779 rc = -EINVAL;
780 goto parse_DFS_referrals_exit;
781 }
782
783 node->path_consumed = path_consumed;
784 }
785
786 node->server_type = le16_to_cpu(ref->ServerType);
787 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags);
788
789 /* copy DfsPath */
790 if (le16_to_cpu(ref->DfsPathOffset) > data_end - (char *)ref) {
791 rc = -EINVAL;
792 goto parse_DFS_referrals_exit;
793 }
794 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset);
795 max_len = data_end - temp;
796 node->path_name = cifs_strndup_from_utf16(temp, max_len,
797 is_unicode, nls_codepage);
798 if (!node->path_name) {
799 rc = -ENOMEM;
800 goto parse_DFS_referrals_exit;
801 }
802
803 /* copy link target UNC */
804 if (le16_to_cpu(ref->NetworkAddressOffset) > data_end - (char *)ref) {
805 rc = -EINVAL;
806 goto parse_DFS_referrals_exit;
807 }
808 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset);
809 max_len = data_end - temp;
810 node->node_name = cifs_strndup_from_utf16(temp, max_len,
811 is_unicode, nls_codepage);
812 if (!node->node_name) {
813 rc = -ENOMEM;
814 goto parse_DFS_referrals_exit;
815 }
816
817 node->ttl = le32_to_cpu(ref->TimeToLive);
818
819 ref++;
820 }
821
822 parse_DFS_referrals_exit:
823 if (rc) {
824 free_dfs_info_array(*target_nodes, *num_of_nodes);
825 *target_nodes = NULL;
826 *num_of_nodes = 0;
827 }
828 return rc;
829 }
830
extract_unc_hostname(const char * unc,const char ** h,size_t * len)831 void extract_unc_hostname(const char *unc, const char **h, size_t *len)
832 {
833 const char *end;
834
835 /* skip initial slashes */
836 while (*unc && (*unc == '\\' || *unc == '/'))
837 unc++;
838
839 end = unc;
840
841 while (*end && !(*end == '\\' || *end == '/'))
842 end++;
843
844 *h = unc;
845 *len = end - unc;
846 }
847
848 /**
849 * copy_path_name - copy src path to dst, possibly truncating
850 * @dst: The destination buffer
851 * @src: The source name
852 *
853 * returns number of bytes written (including trailing nul)
854 */
copy_path_name(char * dst,const char * src)855 int copy_path_name(char *dst, const char *src)
856 {
857 int name_len;
858
859 /*
860 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it
861 * will truncate and strlen(dst) will be PATH_MAX-1
862 */
863 name_len = strscpy(dst, src, PATH_MAX);
864 if (WARN_ON_ONCE(name_len < 0))
865 name_len = PATH_MAX-1;
866
867 /* we count the trailing nul */
868 name_len++;
869 return name_len;
870 }
871
872 struct super_cb_data {
873 void *data;
874 struct super_block *sb;
875 };
876
tcon_super_cb(struct super_block * sb,void * arg)877 static void tcon_super_cb(struct super_block *sb, void *arg)
878 {
879 struct super_cb_data *sd = arg;
880 struct cifs_sb_info *cifs_sb;
881 struct cifs_tcon *t1 = sd->data, *t2;
882
883 if (sd->sb)
884 return;
885
886 cifs_sb = CIFS_SB(sb);
887 t2 = cifs_sb_master_tcon(cifs_sb);
888
889 spin_lock(&t2->tc_lock);
890 if ((t1->ses == t2->ses ||
891 t1->ses->dfs_root_ses == t2->ses->dfs_root_ses) &&
892 t1->ses->server == t2->ses->server &&
893 t2->origin_fullpath &&
894 dfs_src_pathname_equal(t2->origin_fullpath, t1->origin_fullpath))
895 sd->sb = sb;
896 spin_unlock(&t2->tc_lock);
897 }
898
__cifs_get_super(void (* f)(struct super_block *,void *),void * data)899 static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *),
900 void *data)
901 {
902 struct super_cb_data sd = {
903 .data = data,
904 .sb = NULL,
905 };
906 struct file_system_type **fs_type = (struct file_system_type *[]) {
907 &cifs_fs_type, &smb3_fs_type, NULL,
908 };
909
910 for (; *fs_type; fs_type++) {
911 iterate_supers_type(*fs_type, f, &sd);
912 if (sd.sb) {
913 /*
914 * Grab an active reference in order to prevent automounts (DFS links)
915 * of expiring and then freeing up our cifs superblock pointer while
916 * we're doing failover.
917 */
918 cifs_sb_active(sd.sb);
919 return sd.sb;
920 }
921 }
922 pr_warn_once("%s: could not find dfs superblock\n", __func__);
923 return ERR_PTR(-EINVAL);
924 }
925
__cifs_put_super(struct super_block * sb)926 static void __cifs_put_super(struct super_block *sb)
927 {
928 if (!IS_ERR_OR_NULL(sb))
929 cifs_sb_deactive(sb);
930 }
931
cifs_get_dfs_tcon_super(struct cifs_tcon * tcon)932 struct super_block *cifs_get_dfs_tcon_super(struct cifs_tcon *tcon)
933 {
934 spin_lock(&tcon->tc_lock);
935 if (!tcon->origin_fullpath) {
936 spin_unlock(&tcon->tc_lock);
937 return ERR_PTR(-ENOENT);
938 }
939 spin_unlock(&tcon->tc_lock);
940 return __cifs_get_super(tcon_super_cb, tcon);
941 }
942
cifs_put_tcp_super(struct super_block * sb)943 void cifs_put_tcp_super(struct super_block *sb)
944 {
945 __cifs_put_super(sb);
946 }
947
948 #ifdef CONFIG_CIFS_DFS_UPCALL
match_target_ip(struct TCP_Server_Info * server,const char * host,size_t hostlen,bool * result)949 int match_target_ip(struct TCP_Server_Info *server,
950 const char *host, size_t hostlen,
951 bool *result)
952 {
953 struct sockaddr_storage ss;
954 int rc;
955
956 cifs_dbg(FYI, "%s: hostname=%.*s\n", __func__, (int)hostlen, host);
957
958 *result = false;
959
960 rc = dns_resolve_name(server->dns_dom, host, hostlen,
961 (struct sockaddr *)&ss);
962 if (rc < 0)
963 return rc;
964
965 spin_lock(&server->srv_lock);
966 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss);
967 spin_unlock(&server->srv_lock);
968 cifs_dbg(FYI, "%s: ip addresses matched: %s\n", __func__, str_yes_no(*result));
969 return 0;
970 }
971
cifs_update_super_prepath(struct cifs_sb_info * cifs_sb,char * prefix)972 int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)
973 {
974 int rc;
975
976 kfree(cifs_sb->prepath);
977 cifs_sb->prepath = NULL;
978
979 if (prefix && *prefix) {
980 cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC);
981 if (IS_ERR(cifs_sb->prepath)) {
982 rc = PTR_ERR(cifs_sb->prepath);
983 cifs_sb->prepath = NULL;
984 return rc;
985 }
986 if (cifs_sb->prepath)
987 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));
988 }
989
990 atomic_or(CIFS_MOUNT_USE_PREFIX_PATH, &cifs_sb->mnt_cifs_flags);
991 return 0;
992 }
993
994 /*
995 * Handle weird Windows SMB server behaviour. It responds with
996 * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for
997 * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains
998 * non-ASCII unicode symbols.
999 */
cifs_inval_name_dfs_link_error(const unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const char * full_path,bool * islink)1000 int cifs_inval_name_dfs_link_error(const unsigned int xid,
1001 struct cifs_tcon *tcon,
1002 struct cifs_sb_info *cifs_sb,
1003 const char *full_path,
1004 bool *islink)
1005 {
1006 struct TCP_Server_Info *server = tcon->ses->server;
1007 struct cifs_ses *ses = tcon->ses;
1008 size_t len;
1009 char *path;
1010 char *ref_path;
1011
1012 *islink = false;
1013
1014 /*
1015 * Fast path - skip check when @full_path doesn't have a prefix path to
1016 * look up or tcon is not DFS.
1017 */
1018 if (strlen(full_path) < 2 || !cifs_sb ||
1019 (cifs_sb_flags(cifs_sb) & CIFS_MOUNT_NO_DFS) ||
1020 !is_tcon_dfs(tcon))
1021 return 0;
1022
1023 spin_lock(&server->srv_lock);
1024 if (!server->leaf_fullpath) {
1025 spin_unlock(&server->srv_lock);
1026 return 0;
1027 }
1028 spin_unlock(&server->srv_lock);
1029
1030 /*
1031 * Slow path - tcon is DFS and @full_path has prefix path, so attempt
1032 * to get a referral to figure out whether it is an DFS link.
1033 */
1034 len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1;
1035 path = kmalloc(len, GFP_KERNEL);
1036 if (!path)
1037 return -ENOMEM;
1038
1039 scnprintf(path, len, "%s%s", tcon->tree_name, full_path);
1040 ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls,
1041 cifs_remap(cifs_sb));
1042 kfree(path);
1043
1044 if (IS_ERR(ref_path)) {
1045 if (PTR_ERR(ref_path) != -EINVAL)
1046 return PTR_ERR(ref_path);
1047 } else {
1048 struct dfs_info3_param *refs = NULL;
1049 int num_refs = 0;
1050
1051 /*
1052 * XXX: we are not using dfs_cache_find() here because we might
1053 * end up filling all the DFS cache and thus potentially
1054 * removing cached DFS targets that the client would eventually
1055 * need during failover.
1056 */
1057 ses = CIFS_DFS_ROOT_SES(ses);
1058 if (ses->server->ops->get_dfs_refer &&
1059 !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs,
1060 &num_refs, cifs_sb->local_nls,
1061 cifs_remap(cifs_sb)))
1062 *islink = refs[0].server_type == DFS_TYPE_LINK;
1063 free_dfs_info_array(refs, num_refs);
1064 kfree(ref_path);
1065 }
1066 return 0;
1067 }
1068 #endif
1069
cifs_wait_for_server_reconnect(struct TCP_Server_Info * server,bool retry)1070 int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry)
1071 {
1072 int timeout = 10;
1073 int rc;
1074
1075 spin_lock(&server->srv_lock);
1076 if (server->tcpStatus != CifsNeedReconnect) {
1077 spin_unlock(&server->srv_lock);
1078 return 0;
1079 }
1080 timeout *= server->nr_targets;
1081 spin_unlock(&server->srv_lock);
1082
1083 /*
1084 * Give demultiplex thread up to 10 seconds to each target available for
1085 * reconnect -- should be greater than cifs socket timeout which is 7
1086 * seconds.
1087 *
1088 * On "soft" mounts we wait once. Hard mounts keep retrying until
1089 * process is killed or server comes back on-line.
1090 */
1091 do {
1092 rc = wait_event_interruptible_timeout(server->response_q,
1093 (server->tcpStatus != CifsNeedReconnect),
1094 timeout * HZ);
1095 if (rc < 0) {
1096 cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n",
1097 __func__);
1098 return -ERESTARTSYS;
1099 }
1100
1101 /* are we still trying to reconnect? */
1102 spin_lock(&server->srv_lock);
1103 if (server->tcpStatus != CifsNeedReconnect) {
1104 spin_unlock(&server->srv_lock);
1105 return 0;
1106 }
1107 spin_unlock(&server->srv_lock);
1108 } while (retry);
1109
1110 cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__);
1111 return -EHOSTDOWN;
1112 }
1113