1 /*
2 * fs/cifs/smb2misc.c
3 *
4 * Copyright (C) International Business Machines Corp., 2002,2011
5 * Etersoft, 2012
6 * Author(s): Steve French (sfrench@us.ibm.com)
7 * Pavel Shilovsky (pshilovsky@samba.org) 2012
8 *
9 * This library is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU Lesser General Public License as published
11 * by the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
13 *
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
17 * the GNU Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this library; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23 #include <linux/ctype.h>
24 #include "smb2pdu.h"
25 #include "cifsglob.h"
26 #include "cifsproto.h"
27 #include "smb2proto.h"
28 #include "cifs_debug.h"
29 #include "cifs_unicode.h"
30 #include "smb2status.h"
31
32 static int
check_smb2_hdr(struct smb2_hdr * hdr,__u64 mid)33 check_smb2_hdr(struct smb2_hdr *hdr, __u64 mid)
34 {
35 __u64 wire_mid = le64_to_cpu(hdr->MessageId);
36
37 /*
38 * Make sure that this really is an SMB, that it is a response,
39 * and that the message ids match.
40 */
41 if ((*(__le32 *)hdr->ProtocolId == SMB2_PROTO_NUMBER) &&
42 (mid == wire_mid)) {
43 if (hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
44 return 0;
45 else {
46 /* only one valid case where server sends us request */
47 if (hdr->Command == SMB2_OPLOCK_BREAK)
48 return 0;
49 else
50 cifs_dbg(VFS, "Received Request not response\n");
51 }
52 } else { /* bad signature or mid */
53 if (*(__le32 *)hdr->ProtocolId != SMB2_PROTO_NUMBER)
54 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
55 *(unsigned int *) hdr->ProtocolId);
56 if (mid != wire_mid)
57 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
58 mid, wire_mid);
59 }
60 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
61 return 1;
62 }
63
64 /*
65 * The following table defines the expected "StructureSize" of SMB2 responses
66 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
67 *
68 * Note that commands are defined in smb2pdu.h in le16 but the array below is
69 * indexed by command in host byte order
70 */
71 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
72 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
73 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
74 /* SMB2_LOGOFF */ cpu_to_le16(4),
75 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
76 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
77 /* SMB2_CREATE */ cpu_to_le16(89),
78 /* SMB2_CLOSE */ cpu_to_le16(60),
79 /* SMB2_FLUSH */ cpu_to_le16(4),
80 /* SMB2_READ */ cpu_to_le16(17),
81 /* SMB2_WRITE */ cpu_to_le16(17),
82 /* SMB2_LOCK */ cpu_to_le16(4),
83 /* SMB2_IOCTL */ cpu_to_le16(49),
84 /* BB CHECK this ... not listed in documentation */
85 /* SMB2_CANCEL */ cpu_to_le16(0),
86 /* SMB2_ECHO */ cpu_to_le16(4),
87 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
88 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
89 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
90 /* SMB2_SET_INFO */ cpu_to_le16(2),
91 /* BB FIXME can also be 44 for lease break */
92 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
93 };
94
95 int
smb2_check_message(char * buf,unsigned int length)96 smb2_check_message(char *buf, unsigned int length)
97 {
98 struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
99 struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
100 __u64 mid = le64_to_cpu(hdr->MessageId);
101 __u32 len = get_rfc1002_length(buf);
102 __u32 clc_len; /* calculated length */
103 int command;
104
105 /* BB disable following printk later */
106 cifs_dbg(FYI, "%s length: 0x%x, smb_buf_length: 0x%x\n",
107 __func__, length, len);
108
109 /*
110 * Add function to do table lookup of StructureSize by command
111 * ie Validate the wct via smb2_struct_sizes table above
112 */
113
114 if (length < sizeof(struct smb2_pdu)) {
115 if ((length >= sizeof(struct smb2_hdr)) && (hdr->Status != 0)) {
116 pdu->StructureSize2 = 0;
117 /*
118 * As with SMB/CIFS, on some error cases servers may
119 * not return wct properly
120 */
121 return 0;
122 } else {
123 cifs_dbg(VFS, "Length less than SMB header size\n");
124 }
125 return 1;
126 }
127 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
128 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
129 mid);
130 return 1;
131 }
132
133 if (check_smb2_hdr(hdr, mid))
134 return 1;
135
136 if (hdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
137 cifs_dbg(VFS, "Illegal structure size %u\n",
138 le16_to_cpu(hdr->StructureSize));
139 return 1;
140 }
141
142 command = le16_to_cpu(hdr->Command);
143 if (command >= NUMBER_OF_SMB2_COMMANDS) {
144 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
145 return 1;
146 }
147
148 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
149 if (command != SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0 ||
150 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
151 /* error packets have 9 byte structure size */
152 cifs_dbg(VFS, "Illegal response size %u for command %d\n",
153 le16_to_cpu(pdu->StructureSize2), command);
154 return 1;
155 } else if (command == SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0)
156 && (le16_to_cpu(pdu->StructureSize2) != 44)
157 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
158 /* special case for SMB2.1 lease break message */
159 cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
160 le16_to_cpu(pdu->StructureSize2));
161 return 1;
162 }
163 }
164
165 if (4 + len != length) {
166 cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
167 length, 4 + len, mid);
168 return 1;
169 }
170
171 clc_len = smb2_calc_size(hdr);
172
173 if (4 + len != clc_len) {
174 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
175 clc_len, 4 + len, mid);
176 /* create failed on symlink */
177 if (command == SMB2_CREATE_HE &&
178 hdr->Status == STATUS_STOPPED_ON_SYMLINK)
179 return 0;
180 /* Windows 7 server returns 24 bytes more */
181 if (clc_len + 20 == len && command == SMB2_OPLOCK_BREAK_HE)
182 return 0;
183 /* server can return one byte more due to implied bcc[0] */
184 if (clc_len == 4 + len + 1)
185 return 0;
186
187 /*
188 * MacOS server pads after SMB2.1 write response with 3 bytes
189 * of junk. Other servers match RFC1001 len to actual
190 * SMB2/SMB3 frame length (header + smb2 response specific data)
191 * Log the server error (once), but allow it and continue
192 * since the frame is parseable.
193 */
194 if (clc_len < 4 /* RFC1001 header size */ + len) {
195 printk_once(KERN_WARNING
196 "SMB2 server sent bad RFC1001 len %d not %d\n",
197 len, clc_len - 4);
198 return 0;
199 }
200
201 return 1;
202 }
203 return 0;
204 }
205
206 /*
207 * The size of the variable area depends on the offset and length fields
208 * located in different fields for various SMB2 responses. SMB2 responses
209 * with no variable length info, show an offset of zero for the offset field.
210 */
211 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
212 /* SMB2_NEGOTIATE */ true,
213 /* SMB2_SESSION_SETUP */ true,
214 /* SMB2_LOGOFF */ false,
215 /* SMB2_TREE_CONNECT */ false,
216 /* SMB2_TREE_DISCONNECT */ false,
217 /* SMB2_CREATE */ true,
218 /* SMB2_CLOSE */ false,
219 /* SMB2_FLUSH */ false,
220 /* SMB2_READ */ true,
221 /* SMB2_WRITE */ false,
222 /* SMB2_LOCK */ false,
223 /* SMB2_IOCTL */ true,
224 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
225 /* SMB2_ECHO */ false,
226 /* SMB2_QUERY_DIRECTORY */ true,
227 /* SMB2_CHANGE_NOTIFY */ true,
228 /* SMB2_QUERY_INFO */ true,
229 /* SMB2_SET_INFO */ false,
230 /* SMB2_OPLOCK_BREAK */ false
231 };
232
233 /*
234 * Returns the pointer to the beginning of the data area. Length of the data
235 * area and the offset to it (from the beginning of the smb are also returned.
236 */
237 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * hdr)238 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
239 {
240 *off = 0;
241 *len = 0;
242
243 /* error responses do not have data area */
244 if (hdr->Status && hdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
245 (((struct smb2_err_rsp *)hdr)->StructureSize) ==
246 SMB2_ERROR_STRUCTURE_SIZE2)
247 return NULL;
248
249 /*
250 * Following commands have data areas so we have to get the location
251 * of the data buffer offset and data buffer length for the particular
252 * command.
253 */
254 switch (hdr->Command) {
255 case SMB2_NEGOTIATE:
256 *off = le16_to_cpu(
257 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
258 *len = le16_to_cpu(
259 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
260 break;
261 case SMB2_SESSION_SETUP:
262 *off = le16_to_cpu(
263 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
264 *len = le16_to_cpu(
265 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
266 break;
267 case SMB2_CREATE:
268 *off = le32_to_cpu(
269 ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
270 *len = le32_to_cpu(
271 ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
272 break;
273 case SMB2_QUERY_INFO:
274 *off = le16_to_cpu(
275 ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
276 *len = le32_to_cpu(
277 ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
278 break;
279 case SMB2_READ:
280 *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
281 *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
282 break;
283 case SMB2_QUERY_DIRECTORY:
284 *off = le16_to_cpu(
285 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
286 *len = le32_to_cpu(
287 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
288 break;
289 case SMB2_IOCTL:
290 *off = le32_to_cpu(
291 ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
292 *len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
293 break;
294 case SMB2_CHANGE_NOTIFY:
295 default:
296 /* BB FIXME for unimplemented cases above */
297 cifs_dbg(VFS, "no length check for command\n");
298 break;
299 }
300
301 /*
302 * Invalid length or offset probably means data area is invalid, but
303 * we have little choice but to ignore the data area in this case.
304 */
305 if (*off > 4096) {
306 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
307 *len = 0;
308 *off = 0;
309 } else if (*off < 0) {
310 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
311 *off);
312 *off = 0;
313 *len = 0;
314 } else if (*len < 0) {
315 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
316 *len);
317 *len = 0;
318 } else if (*len > 128 * 1024) {
319 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
320 *len = 0;
321 }
322
323 /* return pointer to beginning of data area, ie offset from SMB start */
324 if ((*off != 0) && (*len != 0))
325 return (char *)(&hdr->ProtocolId[0]) + *off;
326 else
327 return NULL;
328 }
329
330 /*
331 * Calculate the size of the SMB message based on the fixed header
332 * portion, the number of word parameters and the data portion of the message.
333 */
334 unsigned int
smb2_calc_size(void * buf)335 smb2_calc_size(void *buf)
336 {
337 struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
338 struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
339 int offset; /* the offset from the beginning of SMB to data area */
340 int data_length; /* the length of the variable length data area */
341 /* Structure Size has already been checked to make sure it is 64 */
342 int len = 4 + le16_to_cpu(pdu->hdr.StructureSize);
343
344 /*
345 * StructureSize2, ie length of fixed parameter area has already
346 * been checked to make sure it is the correct length.
347 */
348 len += le16_to_cpu(pdu->StructureSize2);
349
350 if (has_smb2_data_area[le16_to_cpu(hdr->Command)] == false)
351 goto calc_size_exit;
352
353 smb2_get_data_area_len(&offset, &data_length, hdr);
354 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
355
356 if (data_length > 0) {
357 /*
358 * Check to make sure that data area begins after fixed area,
359 * Note that last byte of the fixed area is part of data area
360 * for some commands, typically those with odd StructureSize,
361 * so we must add one to the calculation (and 4 to account for
362 * the size of the RFC1001 hdr.
363 */
364 if (offset + 4 + 1 < len) {
365 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
366 offset + 4 + 1, len);
367 data_length = 0;
368 } else {
369 len = 4 + offset + data_length;
370 }
371 }
372 calc_size_exit:
373 cifs_dbg(FYI, "SMB2 len %d\n", len);
374 return len;
375 }
376
377 /* Note: caller must free return buffer */
378 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)379 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
380 {
381 int len;
382 const char *start_of_path;
383 __le16 *to;
384 int map_type;
385
386 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
387 map_type = SFM_MAP_UNI_RSVD;
388 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
389 map_type = SFU_MAP_UNI_RSVD;
390 else
391 map_type = NO_MAP_UNI_RSVD;
392
393 /* Windows doesn't allow paths beginning with \ */
394 if (from[0] == '\\')
395 start_of_path = from + 1;
396 else
397 start_of_path = from;
398 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
399 cifs_sb->local_nls, map_type);
400 return to;
401 }
402
403 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)404 smb2_get_lease_state(struct cifsInodeInfo *cinode)
405 {
406 __le32 lease = 0;
407
408 if (CIFS_CACHE_WRITE(cinode))
409 lease |= SMB2_LEASE_WRITE_CACHING;
410 if (CIFS_CACHE_HANDLE(cinode))
411 lease |= SMB2_LEASE_HANDLE_CACHING;
412 if (CIFS_CACHE_READ(cinode))
413 lease |= SMB2_LEASE_READ_CACHING;
414 return lease;
415 }
416
417 struct smb2_lease_break_work {
418 struct work_struct lease_break;
419 struct tcon_link *tlink;
420 __u8 lease_key[16];
421 __le32 lease_state;
422 };
423
424 static void
cifs_ses_oplock_break(struct work_struct * work)425 cifs_ses_oplock_break(struct work_struct *work)
426 {
427 struct smb2_lease_break_work *lw = container_of(work,
428 struct smb2_lease_break_work, lease_break);
429 int rc;
430
431 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
432 lw->lease_state);
433 cifs_dbg(FYI, "Lease release rc %d\n", rc);
434 cifs_put_tlink(lw->tlink);
435 kfree(lw);
436 }
437
438 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp,struct smb2_lease_break_work * lw)439 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
440 struct smb2_lease_break_work *lw)
441 {
442 bool found;
443 __u8 lease_state;
444 struct list_head *tmp;
445 struct cifsFileInfo *cfile;
446 struct TCP_Server_Info *server = tcon->ses->server;
447 struct cifs_pending_open *open;
448 struct cifsInodeInfo *cinode;
449 int ack_req = le32_to_cpu(rsp->Flags &
450 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
451
452 lease_state = le32_to_cpu(rsp->NewLeaseState);
453
454 list_for_each(tmp, &tcon->openFileList) {
455 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
456 cinode = CIFS_I(d_inode(cfile->dentry));
457
458 if (memcmp(cinode->lease_key, rsp->LeaseKey,
459 SMB2_LEASE_KEY_SIZE))
460 continue;
461
462 cifs_dbg(FYI, "found in the open list\n");
463 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
464 le32_to_cpu(rsp->NewLeaseState));
465
466 server->ops->set_oplock_level(cinode, lease_state, 0, NULL);
467
468 if (ack_req)
469 cfile->oplock_break_cancelled = false;
470 else
471 cfile->oplock_break_cancelled = true;
472
473 queue_work(cifsiod_wq, &cfile->oplock_break);
474 kfree(lw);
475 return true;
476 }
477
478 found = false;
479 list_for_each_entry(open, &tcon->pending_opens, olist) {
480 if (memcmp(open->lease_key, rsp->LeaseKey,
481 SMB2_LEASE_KEY_SIZE))
482 continue;
483
484 if (!found && ack_req) {
485 found = true;
486 memcpy(lw->lease_key, open->lease_key,
487 SMB2_LEASE_KEY_SIZE);
488 lw->tlink = cifs_get_tlink(open->tlink);
489 queue_work(cifsiod_wq, &lw->lease_break);
490 }
491
492 cifs_dbg(FYI, "found in the pending open list\n");
493 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
494 le32_to_cpu(rsp->NewLeaseState));
495
496 open->oplock = lease_state;
497 }
498 return found;
499 }
500
501 static bool
smb2_is_valid_lease_break(char * buffer)502 smb2_is_valid_lease_break(char *buffer)
503 {
504 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
505 struct list_head *tmp, *tmp1, *tmp2;
506 struct TCP_Server_Info *server;
507 struct cifs_ses *ses;
508 struct cifs_tcon *tcon;
509 struct smb2_lease_break_work *lw;
510
511 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
512 if (!lw)
513 return false;
514
515 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
516 lw->lease_state = rsp->NewLeaseState;
517
518 cifs_dbg(FYI, "Checking for lease break\n");
519
520 /* look up tcon based on tid & uid */
521 spin_lock(&cifs_tcp_ses_lock);
522 list_for_each(tmp, &cifs_tcp_ses_list) {
523 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
524
525 list_for_each(tmp1, &server->smb_ses_list) {
526 ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
527
528 spin_lock(&cifs_file_list_lock);
529 list_for_each(tmp2, &ses->tcon_list) {
530 tcon = list_entry(tmp2, struct cifs_tcon,
531 tcon_list);
532 cifs_stats_inc(
533 &tcon->stats.cifs_stats.num_oplock_brks);
534 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
535 spin_unlock(&cifs_file_list_lock);
536 spin_unlock(&cifs_tcp_ses_lock);
537 return true;
538 }
539 }
540 spin_unlock(&cifs_file_list_lock);
541 }
542 }
543 spin_unlock(&cifs_tcp_ses_lock);
544 kfree(lw);
545 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
546 return false;
547 }
548
549 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)550 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
551 {
552 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
553 struct list_head *tmp, *tmp1, *tmp2;
554 struct cifs_ses *ses;
555 struct cifs_tcon *tcon;
556 struct cifsInodeInfo *cinode;
557 struct cifsFileInfo *cfile;
558
559 cifs_dbg(FYI, "Checking for oplock break\n");
560
561 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
562 return false;
563
564 if (rsp->StructureSize !=
565 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
566 if (le16_to_cpu(rsp->StructureSize) == 44)
567 return smb2_is_valid_lease_break(buffer);
568 else
569 return false;
570 }
571
572 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
573
574 /* look up tcon based on tid & uid */
575 spin_lock(&cifs_tcp_ses_lock);
576 list_for_each(tmp, &server->smb_ses_list) {
577 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
578 list_for_each(tmp1, &ses->tcon_list) {
579 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
580
581 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
582 spin_lock(&cifs_file_list_lock);
583 list_for_each(tmp2, &tcon->openFileList) {
584 cfile = list_entry(tmp2, struct cifsFileInfo,
585 tlist);
586 if (rsp->PersistentFid !=
587 cfile->fid.persistent_fid ||
588 rsp->VolatileFid !=
589 cfile->fid.volatile_fid)
590 continue;
591
592 cifs_dbg(FYI, "file id match, oplock break\n");
593 cinode = CIFS_I(d_inode(cfile->dentry));
594
595 if (!CIFS_CACHE_WRITE(cinode) &&
596 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
597 cfile->oplock_break_cancelled = true;
598 else
599 cfile->oplock_break_cancelled = false;
600
601 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
602 &cinode->flags);
603
604 /*
605 * Set flag if the server downgrades the oplock
606 * to L2 else clear.
607 */
608 if (rsp->OplockLevel)
609 set_bit(
610 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
611 &cinode->flags);
612 else
613 clear_bit(
614 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
615 &cinode->flags);
616
617 queue_work(cifsiod_wq, &cfile->oplock_break);
618
619 spin_unlock(&cifs_file_list_lock);
620 spin_unlock(&cifs_tcp_ses_lock);
621 return true;
622 }
623 spin_unlock(&cifs_file_list_lock);
624 spin_unlock(&cifs_tcp_ses_lock);
625 cifs_dbg(FYI, "No matching file for oplock break\n");
626 return true;
627 }
628 }
629 spin_unlock(&cifs_tcp_ses_lock);
630 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
631 return false;
632 }
633