Merge tag 'ux500-defconfig-for-arm-soc' of git://git.kernel.org/pub/scm/linux/kernel...
[cascardo/linux.git] / fs / cifs / smb2misc.c
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
33 check_smb2_hdr(struct smb2_hdr *hdr, __u64 mid)
34 {
35         /*
36          * Make sure that this really is an SMB, that it is a response,
37          * and that the message ids match.
38          */
39         if ((*(__le32 *)hdr->ProtocolId == SMB2_PROTO_NUMBER) &&
40             (mid == hdr->MessageId)) {
41                 if (hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
42                         return 0;
43                 else {
44                         /* only one valid case where server sends us request */
45                         if (hdr->Command == SMB2_OPLOCK_BREAK)
46                                 return 0;
47                         else
48                                 cifs_dbg(VFS, "Received Request not response\n");
49                 }
50         } else { /* bad signature or mid */
51                 if (*(__le32 *)hdr->ProtocolId != SMB2_PROTO_NUMBER)
52                         cifs_dbg(VFS, "Bad protocol string signature header %x\n",
53                                  *(unsigned int *) hdr->ProtocolId);
54                 if (mid != hdr->MessageId)
55                         cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
56                                  mid, hdr->MessageId);
57         }
58         cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", hdr->MessageId);
59         return 1;
60 }
61
62 /*
63  *  The following table defines the expected "StructureSize" of SMB2 responses
64  *  in order by SMB2 command.  This is similar to "wct" in SMB/CIFS responses.
65  *
66  *  Note that commands are defined in smb2pdu.h in le16 but the array below is
67  *  indexed by command in host byte order
68  */
69 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
70         /* SMB2_NEGOTIATE */ __constant_cpu_to_le16(65),
71         /* SMB2_SESSION_SETUP */ __constant_cpu_to_le16(9),
72         /* SMB2_LOGOFF */ __constant_cpu_to_le16(4),
73         /* SMB2_TREE_CONNECT */ __constant_cpu_to_le16(16),
74         /* SMB2_TREE_DISCONNECT */ __constant_cpu_to_le16(4),
75         /* SMB2_CREATE */ __constant_cpu_to_le16(89),
76         /* SMB2_CLOSE */ __constant_cpu_to_le16(60),
77         /* SMB2_FLUSH */ __constant_cpu_to_le16(4),
78         /* SMB2_READ */ __constant_cpu_to_le16(17),
79         /* SMB2_WRITE */ __constant_cpu_to_le16(17),
80         /* SMB2_LOCK */ __constant_cpu_to_le16(4),
81         /* SMB2_IOCTL */ __constant_cpu_to_le16(49),
82         /* BB CHECK this ... not listed in documentation */
83         /* SMB2_CANCEL */ __constant_cpu_to_le16(0),
84         /* SMB2_ECHO */ __constant_cpu_to_le16(4),
85         /* SMB2_QUERY_DIRECTORY */ __constant_cpu_to_le16(9),
86         /* SMB2_CHANGE_NOTIFY */ __constant_cpu_to_le16(9),
87         /* SMB2_QUERY_INFO */ __constant_cpu_to_le16(9),
88         /* SMB2_SET_INFO */ __constant_cpu_to_le16(2),
89         /* BB FIXME can also be 44 for lease break */
90         /* SMB2_OPLOCK_BREAK */ __constant_cpu_to_le16(24)
91 };
92
93 int
94 smb2_check_message(char *buf, unsigned int length)
95 {
96         struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
97         struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
98         __u64 mid = hdr->MessageId;
99         __u32 len = get_rfc1002_length(buf);
100         __u32 clc_len;  /* calculated length */
101         int command;
102
103         /* BB disable following printk later */
104         cifs_dbg(FYI, "%s length: 0x%x, smb_buf_length: 0x%x\n",
105                  __func__, length, len);
106
107         /*
108          * Add function to do table lookup of StructureSize by command
109          * ie Validate the wct via smb2_struct_sizes table above
110          */
111
112         if (length < sizeof(struct smb2_pdu)) {
113                 if ((length >= sizeof(struct smb2_hdr)) && (hdr->Status != 0)) {
114                         pdu->StructureSize2 = 0;
115                         /*
116                          * As with SMB/CIFS, on some error cases servers may
117                          * not return wct properly
118                          */
119                         return 0;
120                 } else {
121                         cifs_dbg(VFS, "Length less than SMB header size\n");
122                 }
123                 return 1;
124         }
125         if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
126                 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
127                          mid);
128                 return 1;
129         }
130
131         if (check_smb2_hdr(hdr, mid))
132                 return 1;
133
134         if (hdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
135                 cifs_dbg(VFS, "Illegal structure size %u\n",
136                          le16_to_cpu(hdr->StructureSize));
137                 return 1;
138         }
139
140         command = le16_to_cpu(hdr->Command);
141         if (command >= NUMBER_OF_SMB2_COMMANDS) {
142                 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
143                 return 1;
144         }
145
146         if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
147                 if (command != SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0 ||
148                     pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
149                         /* error packets have 9 byte structure size */
150                         cifs_dbg(VFS, "Illegal response size %u for command %d\n",
151                                  le16_to_cpu(pdu->StructureSize2), command);
152                         return 1;
153                 } else if (command == SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0)
154                            && (le16_to_cpu(pdu->StructureSize2) != 44)
155                            && (le16_to_cpu(pdu->StructureSize2) != 36)) {
156                         /* special case for SMB2.1 lease break message */
157                         cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
158                                  le16_to_cpu(pdu->StructureSize2));
159                         return 1;
160                 }
161         }
162
163         if (4 + len != length) {
164                 cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
165                          length, 4 + len, mid);
166                 return 1;
167         }
168
169         clc_len = smb2_calc_size(hdr);
170
171         if (4 + len != clc_len) {
172                 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
173                          clc_len, 4 + len, mid);
174                 /* Windows 7 server returns 24 bytes more */
175                 if (clc_len + 20 == len && command == SMB2_OPLOCK_BREAK_HE)
176                         return 0;
177                 /* server can return one byte more */
178                 if (clc_len == 4 + len + 1)
179                         return 0;
180                 return 1;
181         }
182         return 0;
183 }
184
185 /*
186  * The size of the variable area depends on the offset and length fields
187  * located in different fields for various SMB2 responses. SMB2 responses
188  * with no variable length info, show an offset of zero for the offset field.
189  */
190 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
191         /* SMB2_NEGOTIATE */ true,
192         /* SMB2_SESSION_SETUP */ true,
193         /* SMB2_LOGOFF */ false,
194         /* SMB2_TREE_CONNECT */ false,
195         /* SMB2_TREE_DISCONNECT */ false,
196         /* SMB2_CREATE */ true,
197         /* SMB2_CLOSE */ false,
198         /* SMB2_FLUSH */ false,
199         /* SMB2_READ */ true,
200         /* SMB2_WRITE */ false,
201         /* SMB2_LOCK */ false,
202         /* SMB2_IOCTL */ true,
203         /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
204         /* SMB2_ECHO */ false,
205         /* SMB2_QUERY_DIRECTORY */ true,
206         /* SMB2_CHANGE_NOTIFY */ true,
207         /* SMB2_QUERY_INFO */ true,
208         /* SMB2_SET_INFO */ false,
209         /* SMB2_OPLOCK_BREAK */ false
210 };
211
212 /*
213  * Returns the pointer to the beginning of the data area. Length of the data
214  * area and the offset to it (from the beginning of the smb are also returned.
215  */
216 char *
217 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
218 {
219         *off = 0;
220         *len = 0;
221
222         /* error responses do not have data area */
223         if (hdr->Status && hdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
224             (((struct smb2_err_rsp *)hdr)->StructureSize) ==
225                                                 SMB2_ERROR_STRUCTURE_SIZE2)
226                 return NULL;
227
228         /*
229          * Following commands have data areas so we have to get the location
230          * of the data buffer offset and data buffer length for the particular
231          * command.
232          */
233         switch (hdr->Command) {
234         case SMB2_NEGOTIATE:
235                 *off = le16_to_cpu(
236                     ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
237                 *len = le16_to_cpu(
238                     ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
239                 break;
240         case SMB2_SESSION_SETUP:
241                 *off = le16_to_cpu(
242                     ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
243                 *len = le16_to_cpu(
244                     ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
245                 break;
246         case SMB2_CREATE:
247                 *off = le32_to_cpu(
248                     ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
249                 *len = le32_to_cpu(
250                     ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
251                 break;
252         case SMB2_QUERY_INFO:
253                 *off = le16_to_cpu(
254                     ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
255                 *len = le32_to_cpu(
256                     ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
257                 break;
258         case SMB2_READ:
259                 *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
260                 *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
261                 break;
262         case SMB2_QUERY_DIRECTORY:
263                 *off = le16_to_cpu(
264                   ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
265                 *len = le32_to_cpu(
266                   ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
267                 break;
268         case SMB2_IOCTL:
269                 *off = le32_to_cpu(
270                   ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
271                 *len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
272                 break;
273         case SMB2_CHANGE_NOTIFY:
274         default:
275                 /* BB FIXME for unimplemented cases above */
276                 cifs_dbg(VFS, "no length check for command\n");
277                 break;
278         }
279
280         /*
281          * Invalid length or offset probably means data area is invalid, but
282          * we have little choice but to ignore the data area in this case.
283          */
284         if (*off > 4096) {
285                 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
286                 *len = 0;
287                 *off = 0;
288         } else if (*off < 0) {
289                 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
290                          *off);
291                 *off = 0;
292                 *len = 0;
293         } else if (*len < 0) {
294                 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
295                          *len);
296                 *len = 0;
297         } else if (*len > 128 * 1024) {
298                 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
299                 *len = 0;
300         }
301
302         /* return pointer to beginning of data area, ie offset from SMB start */
303         if ((*off != 0) && (*len != 0))
304                 return hdr->ProtocolId + *off;
305         else
306                 return NULL;
307 }
308
309 /*
310  * Calculate the size of the SMB message based on the fixed header
311  * portion, the number of word parameters and the data portion of the message.
312  */
313 unsigned int
314 smb2_calc_size(void *buf)
315 {
316         struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
317         struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
318         int offset; /* the offset from the beginning of SMB to data area */
319         int data_length; /* the length of the variable length data area */
320         /* Structure Size has already been checked to make sure it is 64 */
321         int len = 4 + le16_to_cpu(pdu->hdr.StructureSize);
322
323         /*
324          * StructureSize2, ie length of fixed parameter area has already
325          * been checked to make sure it is the correct length.
326          */
327         len += le16_to_cpu(pdu->StructureSize2);
328
329         if (has_smb2_data_area[le16_to_cpu(hdr->Command)] == false)
330                 goto calc_size_exit;
331
332         smb2_get_data_area_len(&offset, &data_length, hdr);
333         cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
334
335         if (data_length > 0) {
336                 /*
337                  * Check to make sure that data area begins after fixed area,
338                  * Note that last byte of the fixed area is part of data area
339                  * for some commands, typically those with odd StructureSize,
340                  * so we must add one to the calculation (and 4 to account for
341                  * the size of the RFC1001 hdr.
342                  */
343                 if (offset + 4 + 1 < len) {
344                         cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
345                                  offset + 4 + 1, len);
346                         data_length = 0;
347                 } else {
348                         len = 4 + offset + data_length;
349                 }
350         }
351 calc_size_exit:
352         cifs_dbg(FYI, "SMB2 len %d\n", len);
353         return len;
354 }
355
356 /* Note: caller must free return buffer */
357 __le16 *
358 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
359 {
360         int len;
361         const char *start_of_path;
362         __le16 *to;
363
364         /* Windows doesn't allow paths beginning with \ */
365         if (from[0] == '\\')
366                 start_of_path = from + 1;
367         else
368                 start_of_path = from;
369         to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
370                                    cifs_sb->local_nls,
371                                    cifs_sb->mnt_cifs_flags &
372                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
373         return to;
374 }
375
376 __le32
377 smb2_get_lease_state(struct cifsInodeInfo *cinode)
378 {
379         if (cinode->clientCanCacheAll)
380                 return SMB2_LEASE_WRITE_CACHING | SMB2_LEASE_READ_CACHING;
381         else if (cinode->clientCanCacheRead)
382                 return SMB2_LEASE_READ_CACHING;
383         return 0;
384 }
385
386 __u8 smb2_map_lease_to_oplock(__le32 lease_state)
387 {
388         if (lease_state & SMB2_LEASE_WRITE_CACHING) {
389                 if (lease_state & SMB2_LEASE_HANDLE_CACHING)
390                         return SMB2_OPLOCK_LEVEL_BATCH;
391                 else
392                         return SMB2_OPLOCK_LEVEL_EXCLUSIVE;
393         } else if (lease_state & SMB2_LEASE_READ_CACHING)
394                 return SMB2_OPLOCK_LEVEL_II;
395         return 0;
396 }
397
398 struct smb2_lease_break_work {
399         struct work_struct lease_break;
400         struct tcon_link *tlink;
401         __u8 lease_key[16];
402         __le32 lease_state;
403 };
404
405 static void
406 cifs_ses_oplock_break(struct work_struct *work)
407 {
408         struct smb2_lease_break_work *lw = container_of(work,
409                                 struct smb2_lease_break_work, lease_break);
410         int rc;
411
412         rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
413                               lw->lease_state);
414         cifs_dbg(FYI, "Lease release rc %d\n", rc);
415         cifs_put_tlink(lw->tlink);
416         kfree(lw);
417 }
418
419 static bool
420 smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
421 {
422         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
423         struct list_head *tmp, *tmp1, *tmp2;
424         struct cifs_ses *ses;
425         struct cifs_tcon *tcon;
426         struct cifsInodeInfo *cinode;
427         struct cifsFileInfo *cfile;
428         struct cifs_pending_open *open;
429         struct smb2_lease_break_work *lw;
430         bool found;
431         int ack_req = le32_to_cpu(rsp->Flags &
432                                   SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
433
434         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
435         if (!lw)
436                 return false;
437
438         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
439         lw->lease_state = rsp->NewLeaseState;
440
441         cifs_dbg(FYI, "Checking for lease break\n");
442
443         /* look up tcon based on tid & uid */
444         spin_lock(&cifs_tcp_ses_lock);
445         list_for_each(tmp, &server->smb_ses_list) {
446                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
447
448                 spin_lock(&cifs_file_list_lock);
449                 list_for_each(tmp1, &ses->tcon_list) {
450                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
451
452                         cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
453                         list_for_each(tmp2, &tcon->openFileList) {
454                                 cfile = list_entry(tmp2, struct cifsFileInfo,
455                                                    tlist);
456                                 cinode = CIFS_I(cfile->dentry->d_inode);
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%d\n",
464                                          le32_to_cpu(rsp->NewLeaseState));
465
466                                 smb2_set_oplock_level(cinode,
467                                   smb2_map_lease_to_oplock(rsp->NewLeaseState));
468
469                                 if (ack_req)
470                                         cfile->oplock_break_cancelled = false;
471                                 else
472                                         cfile->oplock_break_cancelled = true;
473
474                                 queue_work(cifsiod_wq, &cfile->oplock_break);
475
476                                 spin_unlock(&cifs_file_list_lock);
477                                 spin_unlock(&cifs_tcp_ses_lock);
478                                 return true;
479                         }
480
481                         found = false;
482                         list_for_each_entry(open, &tcon->pending_opens, olist) {
483                                 if (memcmp(open->lease_key, rsp->LeaseKey,
484                                            SMB2_LEASE_KEY_SIZE))
485                                         continue;
486
487                                 if (!found && ack_req) {
488                                         found = true;
489                                         memcpy(lw->lease_key, open->lease_key,
490                                                SMB2_LEASE_KEY_SIZE);
491                                         lw->tlink = cifs_get_tlink(open->tlink);
492                                         queue_work(cifsiod_wq,
493                                                    &lw->lease_break);
494                                 }
495
496                                 cifs_dbg(FYI, "found in the pending open list\n");
497                                 cifs_dbg(FYI, "lease key match, lease break 0x%d\n",
498                                          le32_to_cpu(rsp->NewLeaseState));
499
500                                 open->oplock =
501                                   smb2_map_lease_to_oplock(rsp->NewLeaseState);
502                         }
503                         if (found) {
504                                 spin_unlock(&cifs_file_list_lock);
505                                 spin_unlock(&cifs_tcp_ses_lock);
506                                 return true;
507                         }
508                 }
509                 spin_unlock(&cifs_file_list_lock);
510         }
511         spin_unlock(&cifs_tcp_ses_lock);
512         kfree(lw);
513         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
514         return false;
515 }
516
517 bool
518 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
519 {
520         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
521         struct list_head *tmp, *tmp1, *tmp2;
522         struct cifs_ses *ses;
523         struct cifs_tcon *tcon;
524         struct cifsInodeInfo *cinode;
525         struct cifsFileInfo *cfile;
526
527         cifs_dbg(FYI, "Checking for oplock break\n");
528
529         if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
530                 return false;
531
532         if (rsp->StructureSize !=
533                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
534                 if (le16_to_cpu(rsp->StructureSize) == 44)
535                         return smb2_is_valid_lease_break(buffer, server);
536                 else
537                         return false;
538         }
539
540         cifs_dbg(FYI, "oplock level 0x%d\n", rsp->OplockLevel);
541
542         /* look up tcon based on tid & uid */
543         spin_lock(&cifs_tcp_ses_lock);
544         list_for_each(tmp, &server->smb_ses_list) {
545                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
546                 list_for_each(tmp1, &ses->tcon_list) {
547                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
548
549                         cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
550                         spin_lock(&cifs_file_list_lock);
551                         list_for_each(tmp2, &tcon->openFileList) {
552                                 cfile = list_entry(tmp2, struct cifsFileInfo,
553                                                      tlist);
554                                 if (rsp->PersistentFid !=
555                                     cfile->fid.persistent_fid ||
556                                     rsp->VolatileFid !=
557                                     cfile->fid.volatile_fid)
558                                         continue;
559
560                                 cifs_dbg(FYI, "file id match, oplock break\n");
561                                 cinode = CIFS_I(cfile->dentry->d_inode);
562
563                                 if (!cinode->clientCanCacheAll &&
564                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
565                                         cfile->oplock_break_cancelled = true;
566                                 else
567                                         cfile->oplock_break_cancelled = false;
568
569                                 smb2_set_oplock_level(cinode,
570                                   rsp->OplockLevel ? SMB2_OPLOCK_LEVEL_II : 0);
571
572                                 queue_work(cifsiod_wq, &cfile->oplock_break);
573
574                                 spin_unlock(&cifs_file_list_lock);
575                                 spin_unlock(&cifs_tcp_ses_lock);
576                                 return true;
577                         }
578                         spin_unlock(&cifs_file_list_lock);
579                         spin_unlock(&cifs_tcp_ses_lock);
580                         cifs_dbg(FYI, "No matching file for oplock break\n");
581                         return true;
582                 }
583         }
584         spin_unlock(&cifs_tcp_ses_lock);
585         cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
586         return false;
587 }