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 * Some windows servers (win2016) will pad also the final
189 * PDU in a compound to 8 bytes.
190 */
191 if (((clc_len + 7) & ~7) == len)
192 return 0;
193
194 /*
195 * MacOS server pads after SMB2.1 write response with 3 bytes
196 * of junk. Other servers match RFC1001 len to actual
197 * SMB2/SMB3 frame length (header + smb2 response specific data)
198 * Log the server error (once), but allow it and continue
199 * since the frame is parseable.
200 */
201 if (clc_len < 4 /* RFC1001 header size */ + len) {
202 printk_once(KERN_WARNING
203 "SMB2 server sent bad RFC1001 len %d not %d\n",
204 len, clc_len - 4);
205 return 0;
206 }
207
208 return 1;
209 }
210 return 0;
211 }
212
213 /*
214 * The size of the variable area depends on the offset and length fields
215 * located in different fields for various SMB2 responses. SMB2 responses
216 * with no variable length info, show an offset of zero for the offset field.
217 */
218 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
219 /* SMB2_NEGOTIATE */ true,
220 /* SMB2_SESSION_SETUP */ true,
221 /* SMB2_LOGOFF */ false,
222 /* SMB2_TREE_CONNECT */ false,
223 /* SMB2_TREE_DISCONNECT */ false,
224 /* SMB2_CREATE */ true,
225 /* SMB2_CLOSE */ false,
226 /* SMB2_FLUSH */ false,
227 /* SMB2_READ */ true,
228 /* SMB2_WRITE */ false,
229 /* SMB2_LOCK */ false,
230 /* SMB2_IOCTL */ true,
231 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
232 /* SMB2_ECHO */ false,
233 /* SMB2_QUERY_DIRECTORY */ true,
234 /* SMB2_CHANGE_NOTIFY */ true,
235 /* SMB2_QUERY_INFO */ true,
236 /* SMB2_SET_INFO */ false,
237 /* SMB2_OPLOCK_BREAK */ false
238 };
239
240 /*
241 * Returns the pointer to the beginning of the data area. Length of the data
242 * area and the offset to it (from the beginning of the smb are also returned.
243 */
244 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * hdr)245 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
246 {
247 *off = 0;
248 *len = 0;
249
250 /* error responses do not have data area */
251 if (hdr->Status && hdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
252 (((struct smb2_err_rsp *)hdr)->StructureSize) ==
253 SMB2_ERROR_STRUCTURE_SIZE2)
254 return NULL;
255
256 /*
257 * Following commands have data areas so we have to get the location
258 * of the data buffer offset and data buffer length for the particular
259 * command.
260 */
261 switch (hdr->Command) {
262 case SMB2_NEGOTIATE:
263 *off = le16_to_cpu(
264 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
265 *len = le16_to_cpu(
266 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
267 break;
268 case SMB2_SESSION_SETUP:
269 *off = le16_to_cpu(
270 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
271 *len = le16_to_cpu(
272 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
273 break;
274 case SMB2_CREATE:
275 *off = le32_to_cpu(
276 ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
277 *len = le32_to_cpu(
278 ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
279 break;
280 case SMB2_QUERY_INFO:
281 *off = le16_to_cpu(
282 ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
283 *len = le32_to_cpu(
284 ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
285 break;
286 case SMB2_READ:
287 *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
288 *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
289 break;
290 case SMB2_QUERY_DIRECTORY:
291 *off = le16_to_cpu(
292 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
293 *len = le32_to_cpu(
294 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
295 break;
296 case SMB2_IOCTL:
297 *off = le32_to_cpu(
298 ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
299 *len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
300 break;
301 case SMB2_CHANGE_NOTIFY:
302 default:
303 /* BB FIXME for unimplemented cases above */
304 cifs_dbg(VFS, "no length check for command\n");
305 break;
306 }
307
308 /*
309 * Invalid length or offset probably means data area is invalid, but
310 * we have little choice but to ignore the data area in this case.
311 */
312 if (*off > 4096) {
313 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
314 *len = 0;
315 *off = 0;
316 } else if (*off < 0) {
317 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
318 *off);
319 *off = 0;
320 *len = 0;
321 } else if (*len < 0) {
322 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
323 *len);
324 *len = 0;
325 } else if (*len > 128 * 1024) {
326 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
327 *len = 0;
328 }
329
330 /* return pointer to beginning of data area, ie offset from SMB start */
331 if ((*off != 0) && (*len != 0))
332 return (char *)(&hdr->ProtocolId[0]) + *off;
333 else
334 return NULL;
335 }
336
337 /*
338 * Calculate the size of the SMB message based on the fixed header
339 * portion, the number of word parameters and the data portion of the message.
340 */
341 unsigned int
smb2_calc_size(void * buf)342 smb2_calc_size(void *buf)
343 {
344 struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
345 struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
346 int offset; /* the offset from the beginning of SMB to data area */
347 int data_length; /* the length of the variable length data area */
348 /* Structure Size has already been checked to make sure it is 64 */
349 int len = 4 + le16_to_cpu(pdu->hdr.StructureSize);
350
351 /*
352 * StructureSize2, ie length of fixed parameter area has already
353 * been checked to make sure it is the correct length.
354 */
355 len += le16_to_cpu(pdu->StructureSize2);
356
357 if (has_smb2_data_area[le16_to_cpu(hdr->Command)] == false)
358 goto calc_size_exit;
359
360 smb2_get_data_area_len(&offset, &data_length, hdr);
361 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
362
363 if (data_length > 0) {
364 /*
365 * Check to make sure that data area begins after fixed area,
366 * Note that last byte of the fixed area is part of data area
367 * for some commands, typically those with odd StructureSize,
368 * so we must add one to the calculation (and 4 to account for
369 * the size of the RFC1001 hdr.
370 */
371 if (offset + 4 + 1 < len) {
372 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
373 offset + 4 + 1, len);
374 data_length = 0;
375 } else {
376 len = 4 + offset + data_length;
377 }
378 }
379 calc_size_exit:
380 cifs_dbg(FYI, "SMB2 len %d\n", len);
381 return len;
382 }
383
384 /* Note: caller must free return buffer */
385 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)386 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
387 {
388 int len;
389 const char *start_of_path;
390 __le16 *to;
391 int map_type;
392
393 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
394 map_type = SFM_MAP_UNI_RSVD;
395 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
396 map_type = SFU_MAP_UNI_RSVD;
397 else
398 map_type = NO_MAP_UNI_RSVD;
399
400 /* Windows doesn't allow paths beginning with \ */
401 if (from[0] == '\\')
402 start_of_path = from + 1;
403 else
404 start_of_path = from;
405 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
406 cifs_sb->local_nls, map_type);
407 return to;
408 }
409
410 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)411 smb2_get_lease_state(struct cifsInodeInfo *cinode)
412 {
413 __le32 lease = 0;
414
415 if (CIFS_CACHE_WRITE(cinode))
416 lease |= SMB2_LEASE_WRITE_CACHING;
417 if (CIFS_CACHE_HANDLE(cinode))
418 lease |= SMB2_LEASE_HANDLE_CACHING;
419 if (CIFS_CACHE_READ(cinode))
420 lease |= SMB2_LEASE_READ_CACHING;
421 return lease;
422 }
423
424 struct smb2_lease_break_work {
425 struct work_struct lease_break;
426 struct tcon_link *tlink;
427 __u8 lease_key[16];
428 __le32 lease_state;
429 };
430
431 static void
cifs_ses_oplock_break(struct work_struct * work)432 cifs_ses_oplock_break(struct work_struct *work)
433 {
434 struct smb2_lease_break_work *lw = container_of(work,
435 struct smb2_lease_break_work, lease_break);
436 int rc;
437
438 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
439 lw->lease_state);
440 cifs_dbg(FYI, "Lease release rc %d\n", rc);
441 cifs_put_tlink(lw->tlink);
442 kfree(lw);
443 }
444
445 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp,struct smb2_lease_break_work * lw)446 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
447 struct smb2_lease_break_work *lw)
448 {
449 bool found;
450 __u8 lease_state;
451 struct list_head *tmp;
452 struct cifsFileInfo *cfile;
453 struct TCP_Server_Info *server = tcon->ses->server;
454 struct cifs_pending_open *open;
455 struct cifsInodeInfo *cinode;
456 int ack_req = le32_to_cpu(rsp->Flags &
457 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
458
459 lease_state = le32_to_cpu(rsp->NewLeaseState);
460
461 list_for_each(tmp, &tcon->openFileList) {
462 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
463 cinode = CIFS_I(d_inode(cfile->dentry));
464
465 if (memcmp(cinode->lease_key, rsp->LeaseKey,
466 SMB2_LEASE_KEY_SIZE))
467 continue;
468
469 cifs_dbg(FYI, "found in the open list\n");
470 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
471 le32_to_cpu(rsp->NewLeaseState));
472
473 server->ops->set_oplock_level(cinode, lease_state, 0, NULL);
474
475 if (ack_req)
476 cfile->oplock_break_cancelled = false;
477 else
478 cfile->oplock_break_cancelled = true;
479
480 queue_work(cifsiod_wq, &cfile->oplock_break);
481 kfree(lw);
482 return true;
483 }
484
485 found = false;
486 list_for_each_entry(open, &tcon->pending_opens, olist) {
487 if (memcmp(open->lease_key, rsp->LeaseKey,
488 SMB2_LEASE_KEY_SIZE))
489 continue;
490
491 if (!found && ack_req) {
492 found = true;
493 memcpy(lw->lease_key, open->lease_key,
494 SMB2_LEASE_KEY_SIZE);
495 lw->tlink = cifs_get_tlink(open->tlink);
496 queue_work(cifsiod_wq, &lw->lease_break);
497 }
498
499 cifs_dbg(FYI, "found in the pending open list\n");
500 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
501 le32_to_cpu(rsp->NewLeaseState));
502
503 open->oplock = lease_state;
504 }
505 return found;
506 }
507
508 static bool
smb2_is_valid_lease_break(char * buffer)509 smb2_is_valid_lease_break(char *buffer)
510 {
511 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
512 struct list_head *tmp, *tmp1, *tmp2;
513 struct TCP_Server_Info *server;
514 struct cifs_ses *ses;
515 struct cifs_tcon *tcon;
516 struct smb2_lease_break_work *lw;
517
518 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
519 if (!lw)
520 return false;
521
522 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
523 lw->lease_state = rsp->NewLeaseState;
524
525 cifs_dbg(FYI, "Checking for lease break\n");
526
527 /* look up tcon based on tid & uid */
528 spin_lock(&cifs_tcp_ses_lock);
529 list_for_each(tmp, &cifs_tcp_ses_list) {
530 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
531
532 list_for_each(tmp1, &server->smb_ses_list) {
533 ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
534
535 list_for_each(tmp2, &ses->tcon_list) {
536 tcon = list_entry(tmp2, struct cifs_tcon,
537 tcon_list);
538 spin_lock(&tcon->open_file_lock);
539 cifs_stats_inc(
540 &tcon->stats.cifs_stats.num_oplock_brks);
541 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
542 spin_unlock(&tcon->open_file_lock);
543 spin_unlock(&cifs_tcp_ses_lock);
544 return true;
545 }
546 spin_unlock(&tcon->open_file_lock);
547 }
548 }
549 }
550 spin_unlock(&cifs_tcp_ses_lock);
551 kfree(lw);
552 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
553 return false;
554 }
555
556 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)557 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
558 {
559 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
560 struct list_head *tmp, *tmp1, *tmp2;
561 struct cifs_ses *ses;
562 struct cifs_tcon *tcon;
563 struct cifsInodeInfo *cinode;
564 struct cifsFileInfo *cfile;
565
566 cifs_dbg(FYI, "Checking for oplock break\n");
567
568 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
569 return false;
570
571 if (rsp->StructureSize !=
572 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
573 if (le16_to_cpu(rsp->StructureSize) == 44)
574 return smb2_is_valid_lease_break(buffer);
575 else
576 return false;
577 }
578
579 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
580
581 /* look up tcon based on tid & uid */
582 spin_lock(&cifs_tcp_ses_lock);
583 list_for_each(tmp, &server->smb_ses_list) {
584 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
585
586 list_for_each(tmp1, &ses->tcon_list) {
587 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
588
589 spin_lock(&tcon->open_file_lock);
590 list_for_each(tmp2, &tcon->openFileList) {
591 cfile = list_entry(tmp2, struct cifsFileInfo,
592 tlist);
593 if (rsp->PersistentFid !=
594 cfile->fid.persistent_fid ||
595 rsp->VolatileFid !=
596 cfile->fid.volatile_fid)
597 continue;
598
599 cifs_dbg(FYI, "file id match, oplock break\n");
600 cifs_stats_inc(
601 &tcon->stats.cifs_stats.num_oplock_brks);
602 cinode = CIFS_I(d_inode(cfile->dentry));
603 spin_lock(&cfile->file_info_lock);
604 if (!CIFS_CACHE_WRITE(cinode) &&
605 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
606 cfile->oplock_break_cancelled = true;
607 else
608 cfile->oplock_break_cancelled = false;
609
610 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
611 &cinode->flags);
612
613 /*
614 * Set flag if the server downgrades the oplock
615 * to L2 else clear.
616 */
617 if (rsp->OplockLevel)
618 set_bit(
619 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
620 &cinode->flags);
621 else
622 clear_bit(
623 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
624 &cinode->flags);
625 spin_unlock(&cfile->file_info_lock);
626 queue_work(cifsiod_wq, &cfile->oplock_break);
627
628 spin_unlock(&tcon->open_file_lock);
629 spin_unlock(&cifs_tcp_ses_lock);
630 return true;
631 }
632 spin_unlock(&tcon->open_file_lock);
633 }
634 }
635 spin_unlock(&cifs_tcp_ses_lock);
636 cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
637 return true;
638 }
639
640 void
smb2_cancelled_close_fid(struct work_struct * work)641 smb2_cancelled_close_fid(struct work_struct *work)
642 {
643 struct close_cancelled_open *cancelled = container_of(work,
644 struct close_cancelled_open, work);
645
646 cifs_dbg(VFS, "Close unmatched open\n");
647
648 SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
649 cancelled->fid.volatile_fid);
650 cifs_put_tcon(cancelled->tcon);
651 kfree(cancelled);
652 }
653
654 int
smb2_handle_cancelled_mid(char * buffer,struct TCP_Server_Info * server)655 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
656 {
657 struct smb2_hdr *hdr = (struct smb2_hdr *)buffer;
658 struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
659 struct cifs_tcon *tcon;
660 struct close_cancelled_open *cancelled;
661
662 if (hdr->Command != SMB2_CREATE || hdr->Status != STATUS_SUCCESS)
663 return 0;
664
665 cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
666 if (!cancelled)
667 return -ENOMEM;
668
669 tcon = smb2_find_smb_tcon(server, hdr->SessionId, hdr->TreeId);
670 if (!tcon) {
671 kfree(cancelled);
672 return -ENOENT;
673 }
674
675 cancelled->fid.persistent_fid = rsp->PersistentFileId;
676 cancelled->fid.volatile_fid = rsp->VolatileFileId;
677 cancelled->tcon = tcon;
678 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
679 queue_work(cifsiod_wq, &cancelled->work);
680
681 return 0;
682 }
683