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 ((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 (hdr->ProtocolId != SMB2_PROTO_NUMBER)
54 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
55 le32_to_cpu(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,struct TCP_Server_Info * srvr)96 smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
97 {
98 struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
99 struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
100 __u64 mid;
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 (hdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
115 struct smb2_transform_hdr *thdr =
116 (struct smb2_transform_hdr *)buf;
117 struct cifs_ses *ses = NULL;
118 struct list_head *tmp;
119
120 /* decrypt frame now that it is completely read in */
121 spin_lock(&cifs_tcp_ses_lock);
122 list_for_each(tmp, &srvr->smb_ses_list) {
123 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
124 if (ses->Suid == thdr->SessionId)
125 break;
126
127 ses = NULL;
128 }
129 spin_unlock(&cifs_tcp_ses_lock);
130 if (ses == NULL) {
131 cifs_dbg(VFS, "no decryption - session id not found\n");
132 return 1;
133 }
134 }
135
136
137 mid = le64_to_cpu(hdr->MessageId);
138 if (length < sizeof(struct smb2_pdu)) {
139 if ((length >= sizeof(struct smb2_hdr)) && (hdr->Status != 0)) {
140 pdu->StructureSize2 = 0;
141 /*
142 * As with SMB/CIFS, on some error cases servers may
143 * not return wct properly
144 */
145 return 0;
146 } else {
147 cifs_dbg(VFS, "Length less than SMB header size\n");
148 }
149 return 1;
150 }
151 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
152 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
153 mid);
154 return 1;
155 }
156
157 if (check_smb2_hdr(hdr, mid))
158 return 1;
159
160 if (hdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
161 cifs_dbg(VFS, "Illegal structure size %u\n",
162 le16_to_cpu(hdr->StructureSize));
163 return 1;
164 }
165
166 command = le16_to_cpu(hdr->Command);
167 if (command >= NUMBER_OF_SMB2_COMMANDS) {
168 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
169 return 1;
170 }
171
172 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
173 if (command != SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0 ||
174 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
175 /* error packets have 9 byte structure size */
176 cifs_dbg(VFS, "Illegal response size %u for command %d\n",
177 le16_to_cpu(pdu->StructureSize2), command);
178 return 1;
179 } else if (command == SMB2_OPLOCK_BREAK_HE && (hdr->Status == 0)
180 && (le16_to_cpu(pdu->StructureSize2) != 44)
181 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
182 /* special case for SMB2.1 lease break message */
183 cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
184 le16_to_cpu(pdu->StructureSize2));
185 return 1;
186 }
187 }
188
189 if (4 + len != length) {
190 cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
191 length, 4 + len, mid);
192 return 1;
193 }
194
195 clc_len = smb2_calc_size(hdr);
196
197 if (4 + len != clc_len) {
198 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
199 clc_len, 4 + len, mid);
200 /* create failed on symlink */
201 if (command == SMB2_CREATE_HE &&
202 hdr->Status == STATUS_STOPPED_ON_SYMLINK)
203 return 0;
204 /* Windows 7 server returns 24 bytes more */
205 if (clc_len + 20 == len && command == SMB2_OPLOCK_BREAK_HE)
206 return 0;
207 /* server can return one byte more due to implied bcc[0] */
208 if (clc_len == 4 + len + 1)
209 return 0;
210
211 /*
212 * MacOS server pads after SMB2.1 write response with 3 bytes
213 * of junk. Other servers match RFC1001 len to actual
214 * SMB2/SMB3 frame length (header + smb2 response specific data)
215 * Log the server error (once), but allow it and continue
216 * since the frame is parseable.
217 */
218 if (clc_len < 4 /* RFC1001 header size */ + len) {
219 printk_once(KERN_WARNING
220 "SMB2 server sent bad RFC1001 len %d not %d\n",
221 len, clc_len - 4);
222 return 0;
223 }
224
225 return 1;
226 }
227 return 0;
228 }
229
230 /*
231 * The size of the variable area depends on the offset and length fields
232 * located in different fields for various SMB2 responses. SMB2 responses
233 * with no variable length info, show an offset of zero for the offset field.
234 */
235 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
236 /* SMB2_NEGOTIATE */ true,
237 /* SMB2_SESSION_SETUP */ true,
238 /* SMB2_LOGOFF */ false,
239 /* SMB2_TREE_CONNECT */ false,
240 /* SMB2_TREE_DISCONNECT */ false,
241 /* SMB2_CREATE */ true,
242 /* SMB2_CLOSE */ false,
243 /* SMB2_FLUSH */ false,
244 /* SMB2_READ */ true,
245 /* SMB2_WRITE */ false,
246 /* SMB2_LOCK */ false,
247 /* SMB2_IOCTL */ true,
248 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
249 /* SMB2_ECHO */ false,
250 /* SMB2_QUERY_DIRECTORY */ true,
251 /* SMB2_CHANGE_NOTIFY */ true,
252 /* SMB2_QUERY_INFO */ true,
253 /* SMB2_SET_INFO */ false,
254 /* SMB2_OPLOCK_BREAK */ false
255 };
256
257 /*
258 * Returns the pointer to the beginning of the data area. Length of the data
259 * area and the offset to it (from the beginning of the smb are also returned.
260 */
261 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * hdr)262 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
263 {
264 *off = 0;
265 *len = 0;
266
267 /* error responses do not have data area */
268 if (hdr->Status && hdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
269 (((struct smb2_err_rsp *)hdr)->StructureSize) ==
270 SMB2_ERROR_STRUCTURE_SIZE2)
271 return NULL;
272
273 /*
274 * Following commands have data areas so we have to get the location
275 * of the data buffer offset and data buffer length for the particular
276 * command.
277 */
278 switch (hdr->Command) {
279 case SMB2_NEGOTIATE:
280 *off = le16_to_cpu(
281 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
282 *len = le16_to_cpu(
283 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
284 break;
285 case SMB2_SESSION_SETUP:
286 *off = le16_to_cpu(
287 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
288 *len = le16_to_cpu(
289 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
290 break;
291 case SMB2_CREATE:
292 *off = le32_to_cpu(
293 ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
294 *len = le32_to_cpu(
295 ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
296 break;
297 case SMB2_QUERY_INFO:
298 *off = le16_to_cpu(
299 ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
300 *len = le32_to_cpu(
301 ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
302 break;
303 case SMB2_READ:
304 *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
305 *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
306 break;
307 case SMB2_QUERY_DIRECTORY:
308 *off = le16_to_cpu(
309 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
310 *len = le32_to_cpu(
311 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
312 break;
313 case SMB2_IOCTL:
314 *off = le32_to_cpu(
315 ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
316 *len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
317 break;
318 case SMB2_CHANGE_NOTIFY:
319 default:
320 /* BB FIXME for unimplemented cases above */
321 cifs_dbg(VFS, "no length check for command\n");
322 break;
323 }
324
325 /*
326 * Invalid length or offset probably means data area is invalid, but
327 * we have little choice but to ignore the data area in this case.
328 */
329 if (*off > 4096) {
330 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
331 *len = 0;
332 *off = 0;
333 } else if (*off < 0) {
334 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
335 *off);
336 *off = 0;
337 *len = 0;
338 } else if (*len < 0) {
339 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
340 *len);
341 *len = 0;
342 } else if (*len > 128 * 1024) {
343 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
344 *len = 0;
345 }
346
347 /* return pointer to beginning of data area, ie offset from SMB start */
348 if ((*off != 0) && (*len != 0))
349 return (char *)(&hdr->ProtocolId) + *off;
350 else
351 return NULL;
352 }
353
354 /*
355 * Calculate the size of the SMB message based on the fixed header
356 * portion, the number of word parameters and the data portion of the message.
357 */
358 unsigned int
smb2_calc_size(void * buf)359 smb2_calc_size(void *buf)
360 {
361 struct smb2_hdr *hdr = (struct smb2_hdr *)buf;
362 struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
363 int offset; /* the offset from the beginning of SMB to data area */
364 int data_length; /* the length of the variable length data area */
365 /* Structure Size has already been checked to make sure it is 64 */
366 int len = 4 + le16_to_cpu(pdu->hdr.StructureSize);
367
368 /*
369 * StructureSize2, ie length of fixed parameter area has already
370 * been checked to make sure it is the correct length.
371 */
372 len += le16_to_cpu(pdu->StructureSize2);
373
374 if (has_smb2_data_area[le16_to_cpu(hdr->Command)] == false)
375 goto calc_size_exit;
376
377 smb2_get_data_area_len(&offset, &data_length, hdr);
378 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
379
380 if (data_length > 0) {
381 /*
382 * Check to make sure that data area begins after fixed area,
383 * Note that last byte of the fixed area is part of data area
384 * for some commands, typically those with odd StructureSize,
385 * so we must add one to the calculation (and 4 to account for
386 * the size of the RFC1001 hdr.
387 */
388 if (offset + 4 + 1 < len) {
389 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
390 offset + 4 + 1, len);
391 data_length = 0;
392 } else {
393 len = 4 + offset + data_length;
394 }
395 }
396 calc_size_exit:
397 cifs_dbg(FYI, "SMB2 len %d\n", len);
398 return len;
399 }
400
401 /* Note: caller must free return buffer */
402 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)403 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
404 {
405 int len;
406 const char *start_of_path;
407 __le16 *to;
408 int map_type;
409
410 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
411 map_type = SFM_MAP_UNI_RSVD;
412 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
413 map_type = SFU_MAP_UNI_RSVD;
414 else
415 map_type = NO_MAP_UNI_RSVD;
416
417 /* Windows doesn't allow paths beginning with \ */
418 if (from[0] == '\\')
419 start_of_path = from + 1;
420 else
421 start_of_path = from;
422 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
423 cifs_sb->local_nls, map_type);
424 return to;
425 }
426
427 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)428 smb2_get_lease_state(struct cifsInodeInfo *cinode)
429 {
430 __le32 lease = 0;
431
432 if (CIFS_CACHE_WRITE(cinode))
433 lease |= SMB2_LEASE_WRITE_CACHING;
434 if (CIFS_CACHE_HANDLE(cinode))
435 lease |= SMB2_LEASE_HANDLE_CACHING;
436 if (CIFS_CACHE_READ(cinode))
437 lease |= SMB2_LEASE_READ_CACHING;
438 return lease;
439 }
440
441 struct smb2_lease_break_work {
442 struct work_struct lease_break;
443 struct tcon_link *tlink;
444 __u8 lease_key[16];
445 __le32 lease_state;
446 };
447
448 static void
cifs_ses_oplock_break(struct work_struct * work)449 cifs_ses_oplock_break(struct work_struct *work)
450 {
451 struct smb2_lease_break_work *lw = container_of(work,
452 struct smb2_lease_break_work, lease_break);
453 int rc;
454
455 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
456 lw->lease_state);
457 cifs_dbg(FYI, "Lease release rc %d\n", rc);
458 cifs_put_tlink(lw->tlink);
459 kfree(lw);
460 }
461
462 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp,struct smb2_lease_break_work * lw)463 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
464 struct smb2_lease_break_work *lw)
465 {
466 bool found;
467 __u8 lease_state;
468 struct list_head *tmp;
469 struct cifsFileInfo *cfile;
470 struct TCP_Server_Info *server = tcon->ses->server;
471 struct cifs_pending_open *open;
472 struct cifsInodeInfo *cinode;
473 int ack_req = le32_to_cpu(rsp->Flags &
474 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
475
476 lease_state = le32_to_cpu(rsp->NewLeaseState);
477
478 list_for_each(tmp, &tcon->openFileList) {
479 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
480 cinode = CIFS_I(d_inode(cfile->dentry));
481
482 if (memcmp(cinode->lease_key, rsp->LeaseKey,
483 SMB2_LEASE_KEY_SIZE))
484 continue;
485
486 cifs_dbg(FYI, "found in the open list\n");
487 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
488 le32_to_cpu(rsp->NewLeaseState));
489
490 server->ops->set_oplock_level(cinode, lease_state, 0, NULL);
491
492 if (ack_req)
493 cfile->oplock_break_cancelled = false;
494 else
495 cfile->oplock_break_cancelled = true;
496
497 queue_work(cifsoplockd_wq, &cfile->oplock_break);
498 kfree(lw);
499 return true;
500 }
501
502 found = false;
503 list_for_each_entry(open, &tcon->pending_opens, olist) {
504 if (memcmp(open->lease_key, rsp->LeaseKey,
505 SMB2_LEASE_KEY_SIZE))
506 continue;
507
508 if (!found && ack_req) {
509 found = true;
510 memcpy(lw->lease_key, open->lease_key,
511 SMB2_LEASE_KEY_SIZE);
512 lw->tlink = cifs_get_tlink(open->tlink);
513 queue_work(cifsiod_wq, &lw->lease_break);
514 }
515
516 cifs_dbg(FYI, "found in the pending open list\n");
517 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
518 le32_to_cpu(rsp->NewLeaseState));
519
520 open->oplock = lease_state;
521 }
522 return found;
523 }
524
525 static bool
smb2_is_valid_lease_break(char * buffer)526 smb2_is_valid_lease_break(char *buffer)
527 {
528 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
529 struct list_head *tmp, *tmp1, *tmp2;
530 struct TCP_Server_Info *server;
531 struct cifs_ses *ses;
532 struct cifs_tcon *tcon;
533 struct smb2_lease_break_work *lw;
534
535 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
536 if (!lw)
537 return false;
538
539 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
540 lw->lease_state = rsp->NewLeaseState;
541
542 cifs_dbg(FYI, "Checking for lease break\n");
543
544 /* look up tcon based on tid & uid */
545 spin_lock(&cifs_tcp_ses_lock);
546 list_for_each(tmp, &cifs_tcp_ses_list) {
547 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
548
549 list_for_each(tmp1, &server->smb_ses_list) {
550 ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
551
552 list_for_each(tmp2, &ses->tcon_list) {
553 tcon = list_entry(tmp2, struct cifs_tcon,
554 tcon_list);
555 spin_lock(&tcon->open_file_lock);
556 cifs_stats_inc(
557 &tcon->stats.cifs_stats.num_oplock_brks);
558 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
559 spin_unlock(&tcon->open_file_lock);
560 spin_unlock(&cifs_tcp_ses_lock);
561 return true;
562 }
563 spin_unlock(&tcon->open_file_lock);
564 }
565 }
566 }
567 spin_unlock(&cifs_tcp_ses_lock);
568 kfree(lw);
569 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
570 return false;
571 }
572
573 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)574 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
575 {
576 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
577 struct list_head *tmp, *tmp1, *tmp2;
578 struct cifs_ses *ses;
579 struct cifs_tcon *tcon;
580 struct cifsInodeInfo *cinode;
581 struct cifsFileInfo *cfile;
582
583 cifs_dbg(FYI, "Checking for oplock break\n");
584
585 if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
586 return false;
587
588 if (rsp->StructureSize !=
589 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
590 if (le16_to_cpu(rsp->StructureSize) == 44)
591 return smb2_is_valid_lease_break(buffer);
592 else
593 return false;
594 }
595
596 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
597
598 /* look up tcon based on tid & uid */
599 spin_lock(&cifs_tcp_ses_lock);
600 list_for_each(tmp, &server->smb_ses_list) {
601 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
602 list_for_each(tmp1, &ses->tcon_list) {
603 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
604
605 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks);
606 spin_lock(&tcon->open_file_lock);
607 list_for_each(tmp2, &tcon->openFileList) {
608 cfile = list_entry(tmp2, struct cifsFileInfo,
609 tlist);
610 if (rsp->PersistentFid !=
611 cfile->fid.persistent_fid ||
612 rsp->VolatileFid !=
613 cfile->fid.volatile_fid)
614 continue;
615
616 cifs_dbg(FYI, "file id match, oplock break\n");
617 cinode = CIFS_I(d_inode(cfile->dentry));
618 spin_lock(&cfile->file_info_lock);
619 if (!CIFS_CACHE_WRITE(cinode) &&
620 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
621 cfile->oplock_break_cancelled = true;
622 else
623 cfile->oplock_break_cancelled = false;
624
625 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
626 &cinode->flags);
627
628 /*
629 * Set flag if the server downgrades the oplock
630 * to L2 else clear.
631 */
632 if (rsp->OplockLevel)
633 set_bit(
634 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
635 &cinode->flags);
636 else
637 clear_bit(
638 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
639 &cinode->flags);
640 spin_unlock(&cfile->file_info_lock);
641 queue_work(cifsoplockd_wq,
642 &cfile->oplock_break);
643
644 spin_unlock(&tcon->open_file_lock);
645 spin_unlock(&cifs_tcp_ses_lock);
646 return true;
647 }
648 spin_unlock(&tcon->open_file_lock);
649 spin_unlock(&cifs_tcp_ses_lock);
650 cifs_dbg(FYI, "No matching file for oplock break\n");
651 return true;
652 }
653 }
654 spin_unlock(&cifs_tcp_ses_lock);
655 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
656 return false;
657 }
658
659 void
smb2_cancelled_close_fid(struct work_struct * work)660 smb2_cancelled_close_fid(struct work_struct *work)
661 {
662 struct close_cancelled_open *cancelled = container_of(work,
663 struct close_cancelled_open, work);
664
665 cifs_dbg(VFS, "Close unmatched open\n");
666
667 SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
668 cancelled->fid.volatile_fid);
669 cifs_put_tcon(cancelled->tcon);
670 kfree(cancelled);
671 }
672
673 int
smb2_handle_cancelled_mid(char * buffer,struct TCP_Server_Info * server)674 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
675 {
676 struct smb2_hdr *hdr = (struct smb2_hdr *)buffer;
677 struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
678 struct cifs_tcon *tcon;
679 struct close_cancelled_open *cancelled;
680
681 if (hdr->Command != SMB2_CREATE || hdr->Status != STATUS_SUCCESS)
682 return 0;
683
684 cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
685 if (!cancelled)
686 return -ENOMEM;
687
688 tcon = smb2_find_smb_tcon(server, hdr->SessionId, hdr->TreeId);
689 if (!tcon) {
690 kfree(cancelled);
691 return -ENOENT;
692 }
693
694 cancelled->fid.persistent_fid = rsp->PersistentFileId;
695 cancelled->fid.volatile_fid = rsp->VolatileFileId;
696 cancelled->tcon = tcon;
697 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
698 queue_work(cifsiod_wq, &cancelled->work);
699
700 return 0;
701 }
702