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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 "cifspdu.h"
14#include "cifsglob.h"
15#include "cifsproto.h"
16#include "cifs_debug.h"
17#include "smberr.h"
18#include "nterr.h"
19#include "cifs_unicode.h"
20#include "smb2pdu.h"
21#include "cifsfs.h"
22#ifdef CONFIG_CIFS_DFS_UPCALL
23#include "dns_resolve.h"
24#endif
25#include "fs_context.h"
26#include "cached_dir.h"
27
28extern mempool_t *cifs_sm_req_poolp;
29extern mempool_t *cifs_req_poolp;
30
31/* The xid serves as a useful identifier for each incoming vfs request,
32 in a similar way to the mid which is useful to track each sent smb,
33 and CurrentXid can also provide a running counter (although it
34 will eventually wrap past zero) of the total vfs operations handled
35 since the cifs fs was mounted */
36
37unsigned int
38_get_xid(void)
39{
40 unsigned int xid;
41
42 spin_lock(&GlobalMid_Lock);
43 GlobalTotalActiveXid++;
44
45 /* keep high water mark for number of simultaneous ops in filesystem */
46 if (GlobalTotalActiveXid > GlobalMaxActiveXid)
47 GlobalMaxActiveXid = GlobalTotalActiveXid;
48 if (GlobalTotalActiveXid > 65000)
49 cifs_dbg(FYI, "warning: more than 65000 requests active\n");
50 xid = GlobalCurrentXid++;
51 spin_unlock(&GlobalMid_Lock);
52 return xid;
53}
54
55void
56_free_xid(unsigned int xid)
57{
58 spin_lock(&GlobalMid_Lock);
59 /* if (GlobalTotalActiveXid == 0)
60 BUG(); */
61 GlobalTotalActiveXid--;
62 spin_unlock(&GlobalMid_Lock);
63}
64
65struct cifs_ses *
66sesInfoAlloc(void)
67{
68 struct cifs_ses *ret_buf;
69
70 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL);
71 if (ret_buf) {
72 atomic_inc(&sesInfoAllocCount);
73 spin_lock_init(&ret_buf->ses_lock);
74 ret_buf->ses_status = SES_NEW;
75 ++ret_buf->ses_count;
76 INIT_LIST_HEAD(&ret_buf->smb_ses_list);
77 INIT_LIST_HEAD(&ret_buf->tcon_list);
78 mutex_init(&ret_buf->session_mutex);
79 spin_lock_init(&ret_buf->iface_lock);
80 INIT_LIST_HEAD(&ret_buf->iface_list);
81 spin_lock_init(&ret_buf->chan_lock);
82 }
83 return ret_buf;
84}
85
86void
87sesInfoFree(struct cifs_ses *buf_to_free)
88{
89 struct cifs_server_iface *iface = NULL, *niface = NULL;
90
91 if (buf_to_free == NULL) {
92 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n");
93 return;
94 }
95
96 atomic_dec(&sesInfoAllocCount);
97 kfree(buf_to_free->serverOS);
98 kfree(buf_to_free->serverDomain);
99 kfree(buf_to_free->serverNOS);
100 kfree_sensitive(buf_to_free->password);
101 kfree(buf_to_free->user_name);
102 kfree(buf_to_free->domainName);
103 kfree_sensitive(buf_to_free->auth_key.response);
104 spin_lock(&buf_to_free->iface_lock);
105 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list,
106 iface_head)
107 kref_put(&iface->refcount, release_iface);
108 spin_unlock(&buf_to_free->iface_lock);
109 kfree_sensitive(buf_to_free);
110}
111
112struct cifs_tcon *
113tconInfoAlloc(void)
114{
115 struct cifs_tcon *ret_buf;
116
117 ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL);
118 if (!ret_buf)
119 return NULL;
120 ret_buf->cfids = init_cached_dirs();
121 if (!ret_buf->cfids) {
122 kfree(ret_buf);
123 return NULL;
124 }
125
126 atomic_inc(&tconInfoAllocCount);
127 ret_buf->status = TID_NEW;
128 ++ret_buf->tc_count;
129 spin_lock_init(&ret_buf->tc_lock);
130 INIT_LIST_HEAD(&ret_buf->openFileList);
131 INIT_LIST_HEAD(&ret_buf->tcon_list);
132 spin_lock_init(&ret_buf->open_file_lock);
133 spin_lock_init(&ret_buf->stat_lock);
134 atomic_set(&ret_buf->num_local_opens, 0);
135 atomic_set(&ret_buf->num_remote_opens, 0);
136
137 return ret_buf;
138}
139
140void
141tconInfoFree(struct cifs_tcon *tcon)
142{
143 if (tcon == NULL) {
144 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n");
145 return;
146 }
147 free_cached_dirs(tcon->cfids);
148 atomic_dec(&tconInfoAllocCount);
149 kfree(tcon->nativeFileSystem);
150 kfree_sensitive(tcon->password);
151 kfree(tcon);
152}
153
154struct smb_hdr *
155cifs_buf_get(void)
156{
157 struct smb_hdr *ret_buf = NULL;
158 /*
159 * SMB2 header is bigger than CIFS one - no problems to clean some
160 * more bytes for CIFS.
161 */
162 size_t buf_size = sizeof(struct smb2_hdr);
163
164 /*
165 * We could use negotiated size instead of max_msgsize -
166 * but it may be more efficient to always alloc same size
167 * albeit slightly larger than necessary and maxbuffersize
168 * defaults to this and can not be bigger.
169 */
170 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS);
171
172 /* clear the first few header bytes */
173 /* for most paths, more is cleared in header_assemble */
174 memset(ret_buf, 0, buf_size + 3);
175 atomic_inc(&buf_alloc_count);
176#ifdef CONFIG_CIFS_STATS2
177 atomic_inc(&total_buf_alloc_count);
178#endif /* CONFIG_CIFS_STATS2 */
179
180 return ret_buf;
181}
182
183void
184cifs_buf_release(void *buf_to_free)
185{
186 if (buf_to_free == NULL) {
187 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/
188 return;
189 }
190 mempool_free(buf_to_free, cifs_req_poolp);
191
192 atomic_dec(&buf_alloc_count);
193 return;
194}
195
196struct smb_hdr *
197cifs_small_buf_get(void)
198{
199 struct smb_hdr *ret_buf = NULL;
200
201/* We could use negotiated size instead of max_msgsize -
202 but it may be more efficient to always alloc same size
203 albeit slightly larger than necessary and maxbuffersize
204 defaults to this and can not be bigger */
205 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS);
206 /* No need to clear memory here, cleared in header assemble */
207 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/
208 atomic_inc(&small_buf_alloc_count);
209#ifdef CONFIG_CIFS_STATS2
210 atomic_inc(&total_small_buf_alloc_count);
211#endif /* CONFIG_CIFS_STATS2 */
212
213 return ret_buf;
214}
215
216void
217cifs_small_buf_release(void *buf_to_free)
218{
219
220 if (buf_to_free == NULL) {
221 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n");
222 return;
223 }
224 mempool_free(buf_to_free, cifs_sm_req_poolp);
225
226 atomic_dec(&small_buf_alloc_count);
227 return;
228}
229
230void
231free_rsp_buf(int resp_buftype, void *rsp)
232{
233 if (resp_buftype == CIFS_SMALL_BUFFER)
234 cifs_small_buf_release(rsp);
235 else if (resp_buftype == CIFS_LARGE_BUFFER)
236 cifs_buf_release(rsp);
237}
238
239/* NB: MID can not be set if treeCon not passed in, in that
240 case it is responsbility of caller to set the mid */
241void
242header_assemble(struct smb_hdr *buffer, char smb_command /* command */ ,
243 const struct cifs_tcon *treeCon, int word_count
244 /* length of fixed section (word count) in two byte units */)
245{
246 char *temp = (char *) buffer;
247
248 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */
249
250 buffer->smb_buf_length = cpu_to_be32(
251 (2 * word_count) + sizeof(struct smb_hdr) -
252 4 /* RFC 1001 length field does not count */ +
253 2 /* for bcc field itself */) ;
254
255 buffer->Protocol[0] = 0xFF;
256 buffer->Protocol[1] = 'S';
257 buffer->Protocol[2] = 'M';
258 buffer->Protocol[3] = 'B';
259 buffer->Command = smb_command;
260 buffer->Flags = 0x00; /* case sensitive */
261 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES;
262 buffer->Pid = cpu_to_le16((__u16)current->tgid);
263 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16));
264 if (treeCon) {
265 buffer->Tid = treeCon->tid;
266 if (treeCon->ses) {
267 if (treeCon->ses->capabilities & CAP_UNICODE)
268 buffer->Flags2 |= SMBFLG2_UNICODE;
269 if (treeCon->ses->capabilities & CAP_STATUS32)
270 buffer->Flags2 |= SMBFLG2_ERR_STATUS;
271
272 /* Uid is not converted */
273 buffer->Uid = treeCon->ses->Suid;
274 if (treeCon->ses->server)
275 buffer->Mid = get_next_mid(treeCon->ses->server);
276 }
277 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS)
278 buffer->Flags2 |= SMBFLG2_DFS;
279 if (treeCon->nocase)
280 buffer->Flags |= SMBFLG_CASELESS;
281 if ((treeCon->ses) && (treeCon->ses->server))
282 if (treeCon->ses->server->sign)
283 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
284 }
285
286/* endian conversion of flags is now done just before sending */
287 buffer->WordCount = (char) word_count;
288 return;
289}
290
291static int
292check_smb_hdr(struct smb_hdr *smb)
293{
294 /* does it have the right SMB "signature" ? */
295 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) {
296 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n",
297 *(unsigned int *)smb->Protocol);
298 return 1;
299 }
300
301 /* if it's a response then accept */
302 if (smb->Flags & SMBFLG_RESPONSE)
303 return 0;
304
305 /* only one valid case where server sends us request */
306 if (smb->Command == SMB_COM_LOCKING_ANDX)
307 return 0;
308
309 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",
310 get_mid(smb));
311 return 1;
312}
313
314int
315checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server)
316{
317 struct smb_hdr *smb = (struct smb_hdr *)buf;
318 __u32 rfclen = be32_to_cpu(smb->smb_buf_length);
319 __u32 clc_len; /* calculated length */
320 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n",
321 total_read, rfclen);
322
323 /* is this frame too small to even get to a BCC? */
324 if (total_read < 2 + sizeof(struct smb_hdr)) {
325 if ((total_read >= sizeof(struct smb_hdr) - 1)
326 && (smb->Status.CifsError != 0)) {
327 /* it's an error return */
328 smb->WordCount = 0;
329 /* some error cases do not return wct and bcc */
330 return 0;
331 } else if ((total_read == sizeof(struct smb_hdr) + 1) &&
332 (smb->WordCount == 0)) {
333 char *tmp = (char *)smb;
334 /* Need to work around a bug in two servers here */
335 /* First, check if the part of bcc they sent was zero */
336 if (tmp[sizeof(struct smb_hdr)] == 0) {
337 /* some servers return only half of bcc
338 * on simple responses (wct, bcc both zero)
339 * in particular have seen this on
340 * ulogoffX and FindClose. This leaves
341 * one byte of bcc potentially unitialized
342 */
343 /* zero rest of bcc */
344 tmp[sizeof(struct smb_hdr)+1] = 0;
345 return 0;
346 }
347 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n");
348 } else {
349 cifs_dbg(VFS, "Length less than smb header size\n");
350 }
351 return -EIO;
352 }
353
354 /* otherwise, there is enough to get to the BCC */
355 if (check_smb_hdr(smb))
356 return -EIO;
357 clc_len = smbCalcSize(smb);
358
359 if (4 + rfclen != total_read) {
360 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n",
361 rfclen);
362 return -EIO;
363 }
364
365 if (4 + rfclen != clc_len) {
366 __u16 mid = get_mid(smb);
367 /* check if bcc wrapped around for large read responses */
368 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) {
369 /* check if lengths match mod 64K */
370 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF))
371 return 0; /* bcc wrapped */
372 }
373 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n",
374 clc_len, 4 + rfclen, mid);
375
376 if (4 + rfclen < clc_len) {
377 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n",
378 rfclen, mid);
379 return -EIO;
380 } else if (rfclen > clc_len + 512) {
381 /*
382 * Some servers (Windows XP in particular) send more
383 * data than the lengths in the SMB packet would
384 * indicate on certain calls (byte range locks and
385 * trans2 find first calls in particular). While the
386 * client can handle such a frame by ignoring the
387 * trailing data, we choose limit the amount of extra
388 * data to 512 bytes.
389 */
390 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n",
391 rfclen, mid);
392 return -EIO;
393 }
394 }
395 return 0;
396}
397
398bool
399is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv)
400{
401 struct smb_hdr *buf = (struct smb_hdr *)buffer;
402 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf;
403 struct TCP_Server_Info *pserver;
404 struct cifs_ses *ses;
405 struct cifs_tcon *tcon;
406 struct cifsInodeInfo *pCifsInode;
407 struct cifsFileInfo *netfile;
408
409 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n");
410 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) &&
411 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) {
412 struct smb_com_transaction_change_notify_rsp *pSMBr =
413 (struct smb_com_transaction_change_notify_rsp *)buf;
414 struct file_notify_information *pnotify;
415 __u32 data_offset = 0;
416 size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length);
417
418 if (get_bcc(buf) > sizeof(struct file_notify_information)) {
419 data_offset = le32_to_cpu(pSMBr->DataOffset);
420
421 if (data_offset >
422 len - sizeof(struct file_notify_information)) {
423 cifs_dbg(FYI, "Invalid data_offset %u\n",
424 data_offset);
425 return true;
426 }
427 pnotify = (struct file_notify_information *)
428 ((char *)&pSMBr->hdr.Protocol + data_offset);
429 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n",
430 pnotify->FileName, pnotify->Action);
431 /* cifs_dump_mem("Rcvd notify Data: ",buf,
432 sizeof(struct smb_hdr)+60); */
433 return true;
434 }
435 if (pSMBr->hdr.Status.CifsError) {
436 cifs_dbg(FYI, "notify err 0x%x\n",
437 pSMBr->hdr.Status.CifsError);
438 return true;
439 }
440 return false;
441 }
442 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX)
443 return false;
444 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) {
445 /* no sense logging error on invalid handle on oplock
446 break - harmless race between close request and oplock
447 break response is expected from time to time writing out
448 large dirty files cached on the client */
449 if ((NT_STATUS_INVALID_HANDLE) ==
450 le32_to_cpu(pSMB->hdr.Status.CifsError)) {
451 cifs_dbg(FYI, "Invalid handle on oplock break\n");
452 return true;
453 } else if (ERRbadfid ==
454 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) {
455 return true;
456 } else {
457 return false; /* on valid oplock brk we get "request" */
458 }
459 }
460 if (pSMB->hdr.WordCount != 8)
461 return false;
462
463 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n",
464 pSMB->LockType, pSMB->OplockLevel);
465 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE))
466 return false;
467
468 /* If server is a channel, select the primary channel */
469 pserver = CIFS_SERVER_IS_CHAN(srv) ? srv->primary_server : srv;
470
471 /* look up tcon based on tid & uid */
472 spin_lock(&cifs_tcp_ses_lock);
473 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
474 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
475 if (tcon->tid != buf->Tid)
476 continue;
477
478 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
479 spin_lock(&tcon->open_file_lock);
480 list_for_each_entry(netfile, &tcon->openFileList, tlist) {
481 if (pSMB->Fid != netfile->fid.netfid)
482 continue;
483
484 cifs_dbg(FYI, "file id match, oplock break\n");
485 pCifsInode = CIFS_I(d_inode(netfile->dentry));
486
487 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
488 &pCifsInode->flags);
489
490 netfile->oplock_epoch = 0;
491 netfile->oplock_level = pSMB->OplockLevel;
492 netfile->oplock_break_cancelled = false;
493 cifs_queue_oplock_break(netfile);
494
495 spin_unlock(&tcon->open_file_lock);
496 spin_unlock(&cifs_tcp_ses_lock);
497 return true;
498 }
499 spin_unlock(&tcon->open_file_lock);
500 spin_unlock(&cifs_tcp_ses_lock);
501 cifs_dbg(FYI, "No matching file for oplock break\n");
502 return true;
503 }
504 }
505 spin_unlock(&cifs_tcp_ses_lock);
506 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
507 return true;
508}
509
510void
511dump_smb(void *buf, int smb_buf_length)
512{
513 if (traceSMB == 0)
514 return;
515
516 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf,
517 smb_buf_length, true);
518}
519
520void
521cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb)
522{
523 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
524 struct cifs_tcon *tcon = NULL;
525
526 if (cifs_sb->master_tlink)
527 tcon = cifs_sb_master_tcon(cifs_sb);
528
529 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
530 cifs_sb->mnt_cifs_serverino_autodisabled = true;
531 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n",
532 tcon ? tcon->tree_name : "new server");
533 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n");
534 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n");
535
536 }
537}
538
539void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock)
540{
541 oplock &= 0xF;
542
543 if (oplock == OPLOCK_EXCLUSIVE) {
544 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG;
545 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n",
546 &cinode->netfs.inode);
547 } else if (oplock == OPLOCK_READ) {
548 cinode->oplock = CIFS_CACHE_READ_FLG;
549 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n",
550 &cinode->netfs.inode);
551 } else
552 cinode->oplock = 0;
553}
554
555/*
556 * We wait for oplock breaks to be processed before we attempt to perform
557 * writes.
558 */
559int cifs_get_writer(struct cifsInodeInfo *cinode)
560{
561 int rc;
562
563start:
564 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK,
565 TASK_KILLABLE);
566 if (rc)
567 return rc;
568
569 spin_lock(&cinode->writers_lock);
570 if (!cinode->writers)
571 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
572 cinode->writers++;
573 /* Check to see if we have started servicing an oplock break */
574 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) {
575 cinode->writers--;
576 if (cinode->writers == 0) {
577 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
578 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
579 }
580 spin_unlock(&cinode->writers_lock);
581 goto start;
582 }
583 spin_unlock(&cinode->writers_lock);
584 return 0;
585}
586
587void cifs_put_writer(struct cifsInodeInfo *cinode)
588{
589 spin_lock(&cinode->writers_lock);
590 cinode->writers--;
591 if (cinode->writers == 0) {
592 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags);
593 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS);
594 }
595 spin_unlock(&cinode->writers_lock);
596}
597
598/**
599 * cifs_queue_oplock_break - queue the oplock break handler for cfile
600 * @cfile: The file to break the oplock on
601 *
602 * This function is called from the demultiplex thread when it
603 * receives an oplock break for @cfile.
604 *
605 * Assumes the tcon->open_file_lock is held.
606 * Assumes cfile->file_info_lock is NOT held.
607 */
608void cifs_queue_oplock_break(struct cifsFileInfo *cfile)
609{
610 /*
611 * Bump the handle refcount now while we hold the
612 * open_file_lock to enforce the validity of it for the oplock
613 * break handler. The matching put is done at the end of the
614 * handler.
615 */
616 cifsFileInfo_get(cfile);
617
618 queue_work(cifsoplockd_wq, &cfile->oplock_break);
619}
620
621void cifs_done_oplock_break(struct cifsInodeInfo *cinode)
622{
623 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
624 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK);
625}
626
627bool
628backup_cred(struct cifs_sb_info *cifs_sb)
629{
630 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) {
631 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid()))
632 return true;
633 }
634 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) {
635 if (in_group_p(cifs_sb->ctx->backupgid))
636 return true;
637 }
638
639 return false;
640}
641
642void
643cifs_del_pending_open(struct cifs_pending_open *open)
644{
645 spin_lock(&tlink_tcon(open->tlink)->open_file_lock);
646 list_del(&open->olist);
647 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
648}
649
650void
651cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink,
652 struct cifs_pending_open *open)
653{
654 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE);
655 open->oplock = CIFS_OPLOCK_NO_CHANGE;
656 open->tlink = tlink;
657 fid->pending_open = open;
658 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens);
659}
660
661void
662cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink,
663 struct cifs_pending_open *open)
664{
665 spin_lock(&tlink_tcon(tlink)->open_file_lock);
666 cifs_add_pending_open_locked(fid, tlink, open);
667 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock);
668}
669
670/*
671 * Critical section which runs after acquiring deferred_lock.
672 * As there is no reference count on cifs_deferred_close, pdclose
673 * should not be used outside deferred_lock.
674 */
675bool
676cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose)
677{
678 struct cifs_deferred_close *dclose;
679
680 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) {
681 if ((dclose->netfid == cfile->fid.netfid) &&
682 (dclose->persistent_fid == cfile->fid.persistent_fid) &&
683 (dclose->volatile_fid == cfile->fid.volatile_fid)) {
684 *pdclose = dclose;
685 return true;
686 }
687 }
688 return false;
689}
690
691/*
692 * Critical section which runs after acquiring deferred_lock.
693 */
694void
695cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose)
696{
697 bool is_deferred = false;
698 struct cifs_deferred_close *pdclose;
699
700 is_deferred = cifs_is_deferred_close(cfile, &pdclose);
701 if (is_deferred) {
702 kfree(dclose);
703 return;
704 }
705
706 dclose->tlink = cfile->tlink;
707 dclose->netfid = cfile->fid.netfid;
708 dclose->persistent_fid = cfile->fid.persistent_fid;
709 dclose->volatile_fid = cfile->fid.volatile_fid;
710 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes);
711}
712
713/*
714 * Critical section which runs after acquiring deferred_lock.
715 */
716void
717cifs_del_deferred_close(struct cifsFileInfo *cfile)
718{
719 bool is_deferred = false;
720 struct cifs_deferred_close *dclose;
721
722 is_deferred = cifs_is_deferred_close(cfile, &dclose);
723 if (!is_deferred)
724 return;
725 list_del(&dclose->dlist);
726 kfree(dclose);
727}
728
729void
730cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode)
731{
732 struct cifsFileInfo *cfile = NULL;
733 struct file_list *tmp_list, *tmp_next_list;
734 struct list_head file_head;
735
736 if (cifs_inode == NULL)
737 return;
738
739 INIT_LIST_HEAD(&file_head);
740 spin_lock(&cifs_inode->open_file_lock);
741 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) {
742 if (delayed_work_pending(&cfile->deferred)) {
743 if (cancel_delayed_work(&cfile->deferred)) {
744 cifs_del_deferred_close(cfile);
745
746 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);
747 if (tmp_list == NULL)
748 break;
749 tmp_list->cfile = cfile;
750 list_add_tail(&tmp_list->list, &file_head);
751 }
752 }
753 }
754 spin_unlock(&cifs_inode->open_file_lock);
755
756 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
757 _cifsFileInfo_put(tmp_list->cfile, true, false);
758 list_del(&tmp_list->list);
759 kfree(tmp_list);
760 }
761}
762
763void
764cifs_close_all_deferred_files(struct cifs_tcon *tcon)
765{
766 struct cifsFileInfo *cfile;
767 struct file_list *tmp_list, *tmp_next_list;
768 struct list_head file_head;
769
770 INIT_LIST_HEAD(&file_head);
771 spin_lock(&tcon->open_file_lock);
772 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
773 if (delayed_work_pending(&cfile->deferred)) {
774 if (cancel_delayed_work(&cfile->deferred)) {
775 cifs_del_deferred_close(cfile);
776
777 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);
778 if (tmp_list == NULL)
779 break;
780 tmp_list->cfile = cfile;
781 list_add_tail(&tmp_list->list, &file_head);
782 }
783 }
784 }
785 spin_unlock(&tcon->open_file_lock);
786
787 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
788 _cifsFileInfo_put(tmp_list->cfile, true, false);
789 list_del(&tmp_list->list);
790 kfree(tmp_list);
791 }
792}
793void
794cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path)
795{
796 struct cifsFileInfo *cfile;
797 struct file_list *tmp_list, *tmp_next_list;
798 struct list_head file_head;
799 void *page;
800 const char *full_path;
801
802 INIT_LIST_HEAD(&file_head);
803 page = alloc_dentry_path();
804 spin_lock(&tcon->open_file_lock);
805 list_for_each_entry(cfile, &tcon->openFileList, tlist) {
806 full_path = build_path_from_dentry(cfile->dentry, page);
807 if (strstr(full_path, path)) {
808 if (delayed_work_pending(&cfile->deferred)) {
809 if (cancel_delayed_work(&cfile->deferred)) {
810 cifs_del_deferred_close(cfile);
811
812 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC);
813 if (tmp_list == NULL)
814 break;
815 tmp_list->cfile = cfile;
816 list_add_tail(&tmp_list->list, &file_head);
817 }
818 }
819 }
820 }
821 spin_unlock(&tcon->open_file_lock);
822
823 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) {
824 _cifsFileInfo_put(tmp_list->cfile, true, false);
825 list_del(&tmp_list->list);
826 kfree(tmp_list);
827 }
828 free_dentry_path(page);
829}
830
831/* parses DFS referral V3 structure
832 * caller is responsible for freeing target_nodes
833 * returns:
834 * - on success - 0
835 * - on failure - errno
836 */
837int
838parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size,
839 unsigned int *num_of_nodes,
840 struct dfs_info3_param **target_nodes,
841 const struct nls_table *nls_codepage, int remap,
842 const char *searchName, bool is_unicode)
843{
844 int i, rc = 0;
845 char *data_end;
846 struct dfs_referral_level_3 *ref;
847
848 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals);
849
850 if (*num_of_nodes < 1) {
851 cifs_dbg(VFS, "num_referrals: must be at least > 0, but we get num_referrals = %d\n",
852 *num_of_nodes);
853 rc = -EINVAL;
854 goto parse_DFS_referrals_exit;
855 }
856
857 ref = (struct dfs_referral_level_3 *) &(rsp->referrals);
858 if (ref->VersionNumber != cpu_to_le16(3)) {
859 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n",
860 le16_to_cpu(ref->VersionNumber));
861 rc = -EINVAL;
862 goto parse_DFS_referrals_exit;
863 }
864
865 /* get the upper boundary of the resp buffer */
866 data_end = (char *)rsp + rsp_size;
867
868 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n",
869 *num_of_nodes, le32_to_cpu(rsp->DFSFlags));
870
871 *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param),
872 GFP_KERNEL);
873 if (*target_nodes == NULL) {
874 rc = -ENOMEM;
875 goto parse_DFS_referrals_exit;
876 }
877
878 /* collect necessary data from referrals */
879 for (i = 0; i < *num_of_nodes; i++) {
880 char *temp;
881 int max_len;
882 struct dfs_info3_param *node = (*target_nodes)+i;
883
884 node->flags = le32_to_cpu(rsp->DFSFlags);
885 if (is_unicode) {
886 __le16 *tmp = kmalloc(strlen(searchName)*2 + 2,
887 GFP_KERNEL);
888 if (tmp == NULL) {
889 rc = -ENOMEM;
890 goto parse_DFS_referrals_exit;
891 }
892 cifsConvertToUTF16((__le16 *) tmp, searchName,
893 PATH_MAX, nls_codepage, remap);
894 node->path_consumed = cifs_utf16_bytes(tmp,
895 le16_to_cpu(rsp->PathConsumed),
896 nls_codepage);
897 kfree(tmp);
898 } else
899 node->path_consumed = le16_to_cpu(rsp->PathConsumed);
900
901 node->server_type = le16_to_cpu(ref->ServerType);
902 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags);
903
904 /* copy DfsPath */
905 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset);
906 max_len = data_end - temp;
907 node->path_name = cifs_strndup_from_utf16(temp, max_len,
908 is_unicode, nls_codepage);
909 if (!node->path_name) {
910 rc = -ENOMEM;
911 goto parse_DFS_referrals_exit;
912 }
913
914 /* copy link target UNC */
915 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset);
916 max_len = data_end - temp;
917 node->node_name = cifs_strndup_from_utf16(temp, max_len,
918 is_unicode, nls_codepage);
919 if (!node->node_name) {
920 rc = -ENOMEM;
921 goto parse_DFS_referrals_exit;
922 }
923
924 node->ttl = le32_to_cpu(ref->TimeToLive);
925
926 ref++;
927 }
928
929parse_DFS_referrals_exit:
930 if (rc) {
931 free_dfs_info_array(*target_nodes, *num_of_nodes);
932 *target_nodes = NULL;
933 *num_of_nodes = 0;
934 }
935 return rc;
936}
937
938struct cifs_aio_ctx *
939cifs_aio_ctx_alloc(void)
940{
941 struct cifs_aio_ctx *ctx;
942
943 /*
944 * Must use kzalloc to initialize ctx->bv to NULL and ctx->direct_io
945 * to false so that we know when we have to unreference pages within
946 * cifs_aio_ctx_release()
947 */
948 ctx = kzalloc(sizeof(struct cifs_aio_ctx), GFP_KERNEL);
949 if (!ctx)
950 return NULL;
951
952 INIT_LIST_HEAD(&ctx->list);
953 mutex_init(&ctx->aio_mutex);
954 init_completion(&ctx->done);
955 kref_init(&ctx->refcount);
956 return ctx;
957}
958
959void
960cifs_aio_ctx_release(struct kref *refcount)
961{
962 struct cifs_aio_ctx *ctx = container_of(refcount,
963 struct cifs_aio_ctx, refcount);
964
965 cifsFileInfo_put(ctx->cfile);
966
967 /*
968 * ctx->bv is only set if setup_aio_ctx_iter() was call successfuly
969 * which means that iov_iter_get_pages() was a success and thus that
970 * we have taken reference on pages.
971 */
972 if (ctx->bv) {
973 unsigned i;
974
975 for (i = 0; i < ctx->npages; i++) {
976 if (ctx->should_dirty)
977 set_page_dirty(ctx->bv[i].bv_page);
978 put_page(ctx->bv[i].bv_page);
979 }
980 kvfree(ctx->bv);
981 }
982
983 kfree(ctx);
984}
985
986#define CIFS_AIO_KMALLOC_LIMIT (1024 * 1024)
987
988int
989setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw)
990{
991 ssize_t rc;
992 unsigned int cur_npages;
993 unsigned int npages = 0;
994 unsigned int i;
995 size_t len;
996 size_t count = iov_iter_count(iter);
997 unsigned int saved_len;
998 size_t start;
999 unsigned int max_pages = iov_iter_npages(iter, INT_MAX);
1000 struct page **pages = NULL;
1001 struct bio_vec *bv = NULL;
1002
1003 if (iov_iter_is_kvec(iter)) {
1004 memcpy(&ctx->iter, iter, sizeof(*iter));
1005 ctx->len = count;
1006 iov_iter_advance(iter, count);
1007 return 0;
1008 }
1009
1010 if (array_size(max_pages, sizeof(*bv)) <= CIFS_AIO_KMALLOC_LIMIT)
1011 bv = kmalloc_array(max_pages, sizeof(*bv), GFP_KERNEL);
1012
1013 if (!bv) {
1014 bv = vmalloc(array_size(max_pages, sizeof(*bv)));
1015 if (!bv)
1016 return -ENOMEM;
1017 }
1018
1019 if (array_size(max_pages, sizeof(*pages)) <= CIFS_AIO_KMALLOC_LIMIT)
1020 pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL);
1021
1022 if (!pages) {
1023 pages = vmalloc(array_size(max_pages, sizeof(*pages)));
1024 if (!pages) {
1025 kvfree(bv);
1026 return -ENOMEM;
1027 }
1028 }
1029
1030 saved_len = count;
1031
1032 while (count && npages < max_pages) {
1033 rc = iov_iter_get_pages2(iter, pages, count, max_pages, &start);
1034 if (rc < 0) {
1035 cifs_dbg(VFS, "Couldn't get user pages (rc=%zd)\n", rc);
1036 break;
1037 }
1038
1039 if (rc > count) {
1040 cifs_dbg(VFS, "get pages rc=%zd more than %zu\n", rc,
1041 count);
1042 break;
1043 }
1044
1045 count -= rc;
1046 rc += start;
1047 cur_npages = DIV_ROUND_UP(rc, PAGE_SIZE);
1048
1049 if (npages + cur_npages > max_pages) {
1050 cifs_dbg(VFS, "out of vec array capacity (%u vs %u)\n",
1051 npages + cur_npages, max_pages);
1052 break;
1053 }
1054
1055 for (i = 0; i < cur_npages; i++) {
1056 len = rc > PAGE_SIZE ? PAGE_SIZE : rc;
1057 bv[npages + i].bv_page = pages[i];
1058 bv[npages + i].bv_offset = start;
1059 bv[npages + i].bv_len = len - start;
1060 rc -= len;
1061 start = 0;
1062 }
1063
1064 npages += cur_npages;
1065 }
1066
1067 kvfree(pages);
1068 ctx->bv = bv;
1069 ctx->len = saved_len - count;
1070 ctx->npages = npages;
1071 iov_iter_bvec(&ctx->iter, rw, ctx->bv, npages, ctx->len);
1072 return 0;
1073}
1074
1075/**
1076 * cifs_alloc_hash - allocate hash and hash context together
1077 * @name: The name of the crypto hash algo
1078 * @sdesc: SHASH descriptor where to put the pointer to the hash TFM
1079 *
1080 * The caller has to make sure @sdesc is initialized to either NULL or
1081 * a valid context. It can be freed via cifs_free_hash().
1082 */
1083int
1084cifs_alloc_hash(const char *name, struct shash_desc **sdesc)
1085{
1086 int rc = 0;
1087 struct crypto_shash *alg = NULL;
1088
1089 if (*sdesc)
1090 return 0;
1091
1092 alg = crypto_alloc_shash(name, 0, 0);
1093 if (IS_ERR(alg)) {
1094 cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name);
1095 rc = PTR_ERR(alg);
1096 *sdesc = NULL;
1097 return rc;
1098 }
1099
1100 *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL);
1101 if (*sdesc == NULL) {
1102 cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name);
1103 crypto_free_shash(alg);
1104 return -ENOMEM;
1105 }
1106
1107 (*sdesc)->tfm = alg;
1108 return 0;
1109}
1110
1111/**
1112 * cifs_free_hash - free hash and hash context together
1113 * @sdesc: Where to find the pointer to the hash TFM
1114 *
1115 * Freeing a NULL descriptor is safe.
1116 */
1117void
1118cifs_free_hash(struct shash_desc **sdesc)
1119{
1120 if (unlikely(!sdesc) || !*sdesc)
1121 return;
1122
1123 if ((*sdesc)->tfm) {
1124 crypto_free_shash((*sdesc)->tfm);
1125 (*sdesc)->tfm = NULL;
1126 }
1127
1128 kfree_sensitive(*sdesc);
1129 *sdesc = NULL;
1130}
1131
1132/**
1133 * rqst_page_get_length - obtain the length and offset for a page in smb_rqst
1134 * @rqst: The request descriptor
1135 * @page: The index of the page to query
1136 * @len: Where to store the length for this page:
1137 * @offset: Where to store the offset for this page
1138 */
1139void rqst_page_get_length(const struct smb_rqst *rqst, unsigned int page,
1140 unsigned int *len, unsigned int *offset)
1141{
1142 *len = rqst->rq_pagesz;
1143 *offset = (page == 0) ? rqst->rq_offset : 0;
1144
1145 if (rqst->rq_npages == 1 || page == rqst->rq_npages-1)
1146 *len = rqst->rq_tailsz;
1147 else if (page == 0)
1148 *len = rqst->rq_pagesz - rqst->rq_offset;
1149}
1150
1151void extract_unc_hostname(const char *unc, const char **h, size_t *len)
1152{
1153 const char *end;
1154
1155 /* skip initial slashes */
1156 while (*unc && (*unc == '\\' || *unc == '/'))
1157 unc++;
1158
1159 end = unc;
1160
1161 while (*end && !(*end == '\\' || *end == '/'))
1162 end++;
1163
1164 *h = unc;
1165 *len = end - unc;
1166}
1167
1168/**
1169 * copy_path_name - copy src path to dst, possibly truncating
1170 * @dst: The destination buffer
1171 * @src: The source name
1172 *
1173 * returns number of bytes written (including trailing nul)
1174 */
1175int copy_path_name(char *dst, const char *src)
1176{
1177 int name_len;
1178
1179 /*
1180 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it
1181 * will truncate and strlen(dst) will be PATH_MAX-1
1182 */
1183 name_len = strscpy(dst, src, PATH_MAX);
1184 if (WARN_ON_ONCE(name_len < 0))
1185 name_len = PATH_MAX-1;
1186
1187 /* we count the trailing nul */
1188 name_len++;
1189 return name_len;
1190}
1191
1192struct super_cb_data {
1193 void *data;
1194 struct super_block *sb;
1195};
1196
1197static void tcp_super_cb(struct super_block *sb, void *arg)
1198{
1199 struct super_cb_data *sd = arg;
1200 struct TCP_Server_Info *server = sd->data;
1201 struct cifs_sb_info *cifs_sb;
1202 struct cifs_tcon *tcon;
1203
1204 if (sd->sb)
1205 return;
1206
1207 cifs_sb = CIFS_SB(sb);
1208 tcon = cifs_sb_master_tcon(cifs_sb);
1209 if (tcon->ses->server == server)
1210 sd->sb = sb;
1211}
1212
1213static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *),
1214 void *data)
1215{
1216 struct super_cb_data sd = {
1217 .data = data,
1218 .sb = NULL,
1219 };
1220 struct file_system_type **fs_type = (struct file_system_type *[]) {
1221 &cifs_fs_type, &smb3_fs_type, NULL,
1222 };
1223
1224 for (; *fs_type; fs_type++) {
1225 iterate_supers_type(*fs_type, f, &sd);
1226 if (sd.sb) {
1227 /*
1228 * Grab an active reference in order to prevent automounts (DFS links)
1229 * of expiring and then freeing up our cifs superblock pointer while
1230 * we're doing failover.
1231 */
1232 cifs_sb_active(sd.sb);
1233 return sd.sb;
1234 }
1235 }
1236 return ERR_PTR(-EINVAL);
1237}
1238
1239static void __cifs_put_super(struct super_block *sb)
1240{
1241 if (!IS_ERR_OR_NULL(sb))
1242 cifs_sb_deactive(sb);
1243}
1244
1245struct super_block *cifs_get_tcp_super(struct TCP_Server_Info *server)
1246{
1247 return __cifs_get_super(tcp_super_cb, server);
1248}
1249
1250void cifs_put_tcp_super(struct super_block *sb)
1251{
1252 __cifs_put_super(sb);
1253}
1254
1255#ifdef CONFIG_CIFS_DFS_UPCALL
1256int match_target_ip(struct TCP_Server_Info *server,
1257 const char *share, size_t share_len,
1258 bool *result)
1259{
1260 int rc;
1261 char *target;
1262 struct sockaddr_storage ss;
1263
1264 *result = false;
1265
1266 target = kzalloc(share_len + 3, GFP_KERNEL);
1267 if (!target)
1268 return -ENOMEM;
1269
1270 scnprintf(target, share_len + 3, "\\\\%.*s", (int)share_len, share);
1271
1272 cifs_dbg(FYI, "%s: target name: %s\n", __func__, target + 2);
1273
1274 rc = dns_resolve_server_name_to_ip(target, (struct sockaddr *)&ss, NULL);
1275 kfree(target);
1276
1277 if (rc < 0)
1278 return rc;
1279
1280 spin_lock(&server->srv_lock);
1281 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss);
1282 spin_unlock(&server->srv_lock);
1283 cifs_dbg(FYI, "%s: ip addresses match: %u\n", __func__, *result);
1284 return 0;
1285}
1286
1287int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix)
1288{
1289 kfree(cifs_sb->prepath);
1290
1291 if (prefix && *prefix) {
1292 cifs_sb->prepath = kstrdup(prefix, GFP_ATOMIC);
1293 if (!cifs_sb->prepath)
1294 return -ENOMEM;
1295
1296 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb));
1297 } else
1298 cifs_sb->prepath = NULL;
1299
1300 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH;
1301 return 0;
1302}
1303#endif