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 #include "smb2glob.h"
32
33 static int
check_smb2_hdr(struct smb2_sync_hdr * shdr,__u64 mid)34 check_smb2_hdr(struct smb2_sync_hdr *shdr, __u64 mid)
35 {
36 __u64 wire_mid = le64_to_cpu(shdr->MessageId);
37
38 /*
39 * Make sure that this really is an SMB, that it is a response,
40 * and that the message ids match.
41 */
42 if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
43 (mid == wire_mid)) {
44 if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
45 return 0;
46 else {
47 /* only one valid case where server sends us request */
48 if (shdr->Command == SMB2_OPLOCK_BREAK)
49 return 0;
50 else
51 cifs_dbg(VFS, "Received Request not response\n");
52 }
53 } else { /* bad signature or mid */
54 if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
55 cifs_dbg(VFS, "Bad protocol string signature header %x\n",
56 le32_to_cpu(shdr->ProtocolId));
57 if (mid != wire_mid)
58 cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
59 mid, wire_mid);
60 }
61 cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
62 return 1;
63 }
64
65 /*
66 * The following table defines the expected "StructureSize" of SMB2 responses
67 * in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
68 *
69 * Note that commands are defined in smb2pdu.h in le16 but the array below is
70 * indexed by command in host byte order
71 */
72 static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
73 /* SMB2_NEGOTIATE */ cpu_to_le16(65),
74 /* SMB2_SESSION_SETUP */ cpu_to_le16(9),
75 /* SMB2_LOGOFF */ cpu_to_le16(4),
76 /* SMB2_TREE_CONNECT */ cpu_to_le16(16),
77 /* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
78 /* SMB2_CREATE */ cpu_to_le16(89),
79 /* SMB2_CLOSE */ cpu_to_le16(60),
80 /* SMB2_FLUSH */ cpu_to_le16(4),
81 /* SMB2_READ */ cpu_to_le16(17),
82 /* SMB2_WRITE */ cpu_to_le16(17),
83 /* SMB2_LOCK */ cpu_to_le16(4),
84 /* SMB2_IOCTL */ cpu_to_le16(49),
85 /* BB CHECK this ... not listed in documentation */
86 /* SMB2_CANCEL */ cpu_to_le16(0),
87 /* SMB2_ECHO */ cpu_to_le16(4),
88 /* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
89 /* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
90 /* SMB2_QUERY_INFO */ cpu_to_le16(9),
91 /* SMB2_SET_INFO */ cpu_to_le16(2),
92 /* BB FIXME can also be 44 for lease break */
93 /* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
94 };
95
96 int
smb2_check_message(char * buf,unsigned int length,struct TCP_Server_Info * srvr)97 smb2_check_message(char *buf, unsigned int length, struct TCP_Server_Info *srvr)
98 {
99 struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
100 struct smb2_hdr *hdr = &pdu->hdr;
101 struct smb2_sync_hdr *shdr = get_sync_hdr(buf);
102 __u64 mid;
103 __u32 len = get_rfc1002_length(buf);
104 __u32 clc_len; /* calculated length */
105 int command;
106
107 /* BB disable following printk later */
108 cifs_dbg(FYI, "%s length: 0x%x, smb_buf_length: 0x%x\n",
109 __func__, length, len);
110
111 /*
112 * Add function to do table lookup of StructureSize by command
113 * ie Validate the wct via smb2_struct_sizes table above
114 */
115
116 if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
117 struct smb2_transform_hdr *thdr =
118 (struct smb2_transform_hdr *)buf;
119 struct cifs_ses *ses = NULL;
120 struct list_head *tmp;
121
122 /* decrypt frame now that it is completely read in */
123 spin_lock(&cifs_tcp_ses_lock);
124 list_for_each(tmp, &srvr->smb_ses_list) {
125 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
126 if (ses->Suid == thdr->SessionId)
127 break;
128
129 ses = NULL;
130 }
131 spin_unlock(&cifs_tcp_ses_lock);
132 if (ses == NULL) {
133 cifs_dbg(VFS, "no decryption - session id not found\n");
134 return 1;
135 }
136 }
137
138 mid = le64_to_cpu(shdr->MessageId);
139 if (length < sizeof(struct smb2_pdu)) {
140 if ((length >= sizeof(struct smb2_hdr))
141 && (shdr->Status != 0)) {
142 pdu->StructureSize2 = 0;
143 /*
144 * As with SMB/CIFS, on some error cases servers may
145 * not return wct properly
146 */
147 return 0;
148 } else {
149 cifs_dbg(VFS, "Length less than SMB header size\n");
150 }
151 return 1;
152 }
153 if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE - 4) {
154 cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
155 mid);
156 return 1;
157 }
158
159 if (check_smb2_hdr(shdr, mid))
160 return 1;
161
162 if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
163 cifs_dbg(VFS, "Illegal structure size %u\n",
164 le16_to_cpu(shdr->StructureSize));
165 return 1;
166 }
167
168 command = le16_to_cpu(shdr->Command);
169 if (command >= NUMBER_OF_SMB2_COMMANDS) {
170 cifs_dbg(VFS, "Illegal SMB2 command %d\n", command);
171 return 1;
172 }
173
174 if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
175 if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
176 pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2)) {
177 /* error packets have 9 byte structure size */
178 cifs_dbg(VFS, "Illegal response size %u for command %d\n",
179 le16_to_cpu(pdu->StructureSize2), command);
180 return 1;
181 } else if (command == SMB2_OPLOCK_BREAK_HE
182 && (shdr->Status == 0)
183 && (le16_to_cpu(pdu->StructureSize2) != 44)
184 && (le16_to_cpu(pdu->StructureSize2) != 36)) {
185 /* special case for SMB2.1 lease break message */
186 cifs_dbg(VFS, "Illegal response size %d for oplock break\n",
187 le16_to_cpu(pdu->StructureSize2));
188 return 1;
189 }
190 }
191
192 if (4 + len != length) {
193 cifs_dbg(VFS, "Total length %u RFC1002 length %u mismatch mid %llu\n",
194 length, 4 + len, mid);
195 return 1;
196 }
197
198 clc_len = smb2_calc_size(hdr);
199
200 if (4 + len != clc_len) {
201 cifs_dbg(FYI, "Calculated size %u length %u mismatch mid %llu\n",
202 clc_len, 4 + len, mid);
203 /* create failed on symlink */
204 if (command == SMB2_CREATE_HE &&
205 shdr->Status == STATUS_STOPPED_ON_SYMLINK)
206 return 0;
207 /* Windows 7 server returns 24 bytes more */
208 if (clc_len + 20 == len && command == SMB2_OPLOCK_BREAK_HE)
209 return 0;
210 /* server can return one byte more due to implied bcc[0] */
211 if (clc_len == 4 + len + 1)
212 return 0;
213
214 /*
215 * Some windows servers (win2016) will pad also the final
216 * PDU in a compound to 8 bytes.
217 */
218 if (((clc_len + 7) & ~7) == len)
219 return 0;
220
221 /*
222 * MacOS server pads after SMB2.1 write response with 3 bytes
223 * of junk. Other servers match RFC1001 len to actual
224 * SMB2/SMB3 frame length (header + smb2 response specific data)
225 * Log the server error (once), but allow it and continue
226 * since the frame is parseable.
227 */
228 if (clc_len < 4 /* RFC1001 header size */ + len) {
229 printk_once(KERN_WARNING
230 "SMB2 server sent bad RFC1001 len %d not %d\n",
231 len, clc_len - 4);
232 return 0;
233 }
234
235 return 1;
236 }
237 return 0;
238 }
239
240 /*
241 * The size of the variable area depends on the offset and length fields
242 * located in different fields for various SMB2 responses. SMB2 responses
243 * with no variable length info, show an offset of zero for the offset field.
244 */
245 static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
246 /* SMB2_NEGOTIATE */ true,
247 /* SMB2_SESSION_SETUP */ true,
248 /* SMB2_LOGOFF */ false,
249 /* SMB2_TREE_CONNECT */ false,
250 /* SMB2_TREE_DISCONNECT */ false,
251 /* SMB2_CREATE */ true,
252 /* SMB2_CLOSE */ false,
253 /* SMB2_FLUSH */ false,
254 /* SMB2_READ */ true,
255 /* SMB2_WRITE */ false,
256 /* SMB2_LOCK */ false,
257 /* SMB2_IOCTL */ true,
258 /* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
259 /* SMB2_ECHO */ false,
260 /* SMB2_QUERY_DIRECTORY */ true,
261 /* SMB2_CHANGE_NOTIFY */ true,
262 /* SMB2_QUERY_INFO */ true,
263 /* SMB2_SET_INFO */ false,
264 /* SMB2_OPLOCK_BREAK */ false
265 };
266
267 /*
268 * Returns the pointer to the beginning of the data area. Length of the data
269 * area and the offset to it (from the beginning of the smb are also returned.
270 */
271 char *
smb2_get_data_area_len(int * off,int * len,struct smb2_hdr * hdr)272 smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *hdr)
273 {
274 struct smb2_sync_hdr *shdr = get_sync_hdr(hdr);
275 *off = 0;
276 *len = 0;
277
278 /* error responses do not have data area */
279 if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
280 (((struct smb2_err_rsp *)hdr)->StructureSize) ==
281 SMB2_ERROR_STRUCTURE_SIZE2)
282 return NULL;
283
284 /*
285 * Following commands have data areas so we have to get the location
286 * of the data buffer offset and data buffer length for the particular
287 * command.
288 */
289 switch (shdr->Command) {
290 case SMB2_NEGOTIATE:
291 *off = le16_to_cpu(
292 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferOffset);
293 *len = le16_to_cpu(
294 ((struct smb2_negotiate_rsp *)hdr)->SecurityBufferLength);
295 break;
296 case SMB2_SESSION_SETUP:
297 *off = le16_to_cpu(
298 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferOffset);
299 *len = le16_to_cpu(
300 ((struct smb2_sess_setup_rsp *)hdr)->SecurityBufferLength);
301 break;
302 case SMB2_CREATE:
303 *off = le32_to_cpu(
304 ((struct smb2_create_rsp *)hdr)->CreateContextsOffset);
305 *len = le32_to_cpu(
306 ((struct smb2_create_rsp *)hdr)->CreateContextsLength);
307 break;
308 case SMB2_QUERY_INFO:
309 *off = le16_to_cpu(
310 ((struct smb2_query_info_rsp *)hdr)->OutputBufferOffset);
311 *len = le32_to_cpu(
312 ((struct smb2_query_info_rsp *)hdr)->OutputBufferLength);
313 break;
314 case SMB2_READ:
315 *off = ((struct smb2_read_rsp *)hdr)->DataOffset;
316 *len = le32_to_cpu(((struct smb2_read_rsp *)hdr)->DataLength);
317 break;
318 case SMB2_QUERY_DIRECTORY:
319 *off = le16_to_cpu(
320 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferOffset);
321 *len = le32_to_cpu(
322 ((struct smb2_query_directory_rsp *)hdr)->OutputBufferLength);
323 break;
324 case SMB2_IOCTL:
325 *off = le32_to_cpu(
326 ((struct smb2_ioctl_rsp *)hdr)->OutputOffset);
327 *len = le32_to_cpu(((struct smb2_ioctl_rsp *)hdr)->OutputCount);
328 break;
329 case SMB2_CHANGE_NOTIFY:
330 default:
331 /* BB FIXME for unimplemented cases above */
332 cifs_dbg(VFS, "no length check for command\n");
333 break;
334 }
335
336 /*
337 * Invalid length or offset probably means data area is invalid, but
338 * we have little choice but to ignore the data area in this case.
339 */
340 if (*off > 4096) {
341 cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
342 *len = 0;
343 *off = 0;
344 } else if (*off < 0) {
345 cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
346 *off);
347 *off = 0;
348 *len = 0;
349 } else if (*len < 0) {
350 cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
351 *len);
352 *len = 0;
353 } else if (*len > 128 * 1024) {
354 cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
355 *len = 0;
356 }
357
358 /* return pointer to beginning of data area, ie offset from SMB start */
359 if ((*off != 0) && (*len != 0))
360 return (char *)shdr + *off;
361 else
362 return NULL;
363 }
364
365 /*
366 * Calculate the size of the SMB message based on the fixed header
367 * portion, the number of word parameters and the data portion of the message.
368 */
369 unsigned int
smb2_calc_size(void * buf)370 smb2_calc_size(void *buf)
371 {
372 struct smb2_pdu *pdu = (struct smb2_pdu *)buf;
373 struct smb2_hdr *hdr = &pdu->hdr;
374 struct smb2_sync_hdr *shdr = get_sync_hdr(hdr);
375 int offset; /* the offset from the beginning of SMB to data area */
376 int data_length; /* the length of the variable length data area */
377 /* Structure Size has already been checked to make sure it is 64 */
378 int len = 4 + le16_to_cpu(shdr->StructureSize);
379
380 /*
381 * StructureSize2, ie length of fixed parameter area has already
382 * been checked to make sure it is the correct length.
383 */
384 len += le16_to_cpu(pdu->StructureSize2);
385
386 if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
387 goto calc_size_exit;
388
389 smb2_get_data_area_len(&offset, &data_length, hdr);
390 cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
391
392 if (data_length > 0) {
393 /*
394 * Check to make sure that data area begins after fixed area,
395 * Note that last byte of the fixed area is part of data area
396 * for some commands, typically those with odd StructureSize,
397 * so we must add one to the calculation (and 4 to account for
398 * the size of the RFC1001 hdr.
399 */
400 if (offset + 4 + 1 < len) {
401 cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
402 offset + 4 + 1, len);
403 data_length = 0;
404 } else {
405 len = 4 + offset + data_length;
406 }
407 }
408 calc_size_exit:
409 cifs_dbg(FYI, "SMB2 len %d\n", len);
410 return len;
411 }
412
413 /* Note: caller must free return buffer */
414 __le16 *
cifs_convert_path_to_utf16(const char * from,struct cifs_sb_info * cifs_sb)415 cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
416 {
417 int len;
418 const char *start_of_path;
419 __le16 *to;
420 int map_type;
421
422 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
423 map_type = SFM_MAP_UNI_RSVD;
424 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
425 map_type = SFU_MAP_UNI_RSVD;
426 else
427 map_type = NO_MAP_UNI_RSVD;
428
429 /* Windows doesn't allow paths beginning with \ */
430 if (from[0] == '\\')
431 start_of_path = from + 1;
432 else
433 start_of_path = from;
434 to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
435 cifs_sb->local_nls, map_type);
436 return to;
437 }
438
439 __le32
smb2_get_lease_state(struct cifsInodeInfo * cinode)440 smb2_get_lease_state(struct cifsInodeInfo *cinode)
441 {
442 __le32 lease = 0;
443
444 if (CIFS_CACHE_WRITE(cinode))
445 lease |= SMB2_LEASE_WRITE_CACHING;
446 if (CIFS_CACHE_HANDLE(cinode))
447 lease |= SMB2_LEASE_HANDLE_CACHING;
448 if (CIFS_CACHE_READ(cinode))
449 lease |= SMB2_LEASE_READ_CACHING;
450 return lease;
451 }
452
453 struct smb2_lease_break_work {
454 struct work_struct lease_break;
455 struct tcon_link *tlink;
456 __u8 lease_key[16];
457 __le32 lease_state;
458 };
459
460 static void
cifs_ses_oplock_break(struct work_struct * work)461 cifs_ses_oplock_break(struct work_struct *work)
462 {
463 struct smb2_lease_break_work *lw = container_of(work,
464 struct smb2_lease_break_work, lease_break);
465 int rc;
466
467 rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
468 lw->lease_state);
469 cifs_dbg(FYI, "Lease release rc %d\n", rc);
470 cifs_put_tlink(lw->tlink);
471 kfree(lw);
472 }
473
474 static bool
smb2_tcon_has_lease(struct cifs_tcon * tcon,struct smb2_lease_break * rsp,struct smb2_lease_break_work * lw)475 smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp,
476 struct smb2_lease_break_work *lw)
477 {
478 bool found;
479 __u8 lease_state;
480 struct list_head *tmp;
481 struct cifsFileInfo *cfile;
482 struct cifs_pending_open *open;
483 struct cifsInodeInfo *cinode;
484 int ack_req = le32_to_cpu(rsp->Flags &
485 SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
486
487 lease_state = le32_to_cpu(rsp->NewLeaseState);
488
489 list_for_each(tmp, &tcon->openFileList) {
490 cfile = list_entry(tmp, struct cifsFileInfo, tlist);
491 cinode = CIFS_I(d_inode(cfile->dentry));
492
493 if (memcmp(cinode->lease_key, rsp->LeaseKey,
494 SMB2_LEASE_KEY_SIZE))
495 continue;
496
497 cifs_dbg(FYI, "found in the open list\n");
498 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
499 le32_to_cpu(rsp->NewLeaseState));
500
501 if (ack_req)
502 cfile->oplock_break_cancelled = false;
503 else
504 cfile->oplock_break_cancelled = true;
505
506 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
507
508 /*
509 * Set or clear flags depending on the lease state being READ.
510 * HANDLE caching flag should be added when the client starts
511 * to defer closing remote file handles with HANDLE leases.
512 */
513 if (lease_state & SMB2_LEASE_READ_CACHING_HE)
514 set_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
515 &cinode->flags);
516 else
517 clear_bit(CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
518 &cinode->flags);
519
520 cifs_queue_oplock_break(cfile);
521 kfree(lw);
522 return true;
523 }
524
525 found = false;
526 list_for_each_entry(open, &tcon->pending_opens, olist) {
527 if (memcmp(open->lease_key, rsp->LeaseKey,
528 SMB2_LEASE_KEY_SIZE))
529 continue;
530
531 if (!found && ack_req) {
532 found = true;
533 memcpy(lw->lease_key, open->lease_key,
534 SMB2_LEASE_KEY_SIZE);
535 lw->tlink = cifs_get_tlink(open->tlink);
536 queue_work(cifsiod_wq, &lw->lease_break);
537 }
538
539 cifs_dbg(FYI, "found in the pending open list\n");
540 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
541 le32_to_cpu(rsp->NewLeaseState));
542
543 open->oplock = lease_state;
544 }
545 return found;
546 }
547
548 static bool
smb2_is_valid_lease_break(char * buffer)549 smb2_is_valid_lease_break(char *buffer)
550 {
551 struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
552 struct list_head *tmp, *tmp1, *tmp2;
553 struct TCP_Server_Info *server;
554 struct cifs_ses *ses;
555 struct cifs_tcon *tcon;
556 struct smb2_lease_break_work *lw;
557
558 lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
559 if (!lw)
560 return false;
561
562 INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
563 lw->lease_state = rsp->NewLeaseState;
564
565 cifs_dbg(FYI, "Checking for lease break\n");
566
567 /* look up tcon based on tid & uid */
568 spin_lock(&cifs_tcp_ses_lock);
569 list_for_each(tmp, &cifs_tcp_ses_list) {
570 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
571
572 list_for_each(tmp1, &server->smb_ses_list) {
573 ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
574
575 list_for_each(tmp2, &ses->tcon_list) {
576 tcon = list_entry(tmp2, struct cifs_tcon,
577 tcon_list);
578 spin_lock(&tcon->open_file_lock);
579 cifs_stats_inc(
580 &tcon->stats.cifs_stats.num_oplock_brks);
581 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
582 spin_unlock(&tcon->open_file_lock);
583 spin_unlock(&cifs_tcp_ses_lock);
584 return true;
585 }
586 spin_unlock(&tcon->open_file_lock);
587 }
588 }
589 }
590 spin_unlock(&cifs_tcp_ses_lock);
591 kfree(lw);
592 cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
593 return false;
594 }
595
596 bool
smb2_is_valid_oplock_break(char * buffer,struct TCP_Server_Info * server)597 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
598 {
599 struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
600 struct list_head *tmp, *tmp1, *tmp2;
601 struct cifs_ses *ses;
602 struct cifs_tcon *tcon;
603 struct cifsInodeInfo *cinode;
604 struct cifsFileInfo *cfile;
605
606 cifs_dbg(FYI, "Checking for oplock break\n");
607
608 if (rsp->hdr.sync_hdr.Command != SMB2_OPLOCK_BREAK)
609 return false;
610
611 if (rsp->StructureSize !=
612 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
613 if (le16_to_cpu(rsp->StructureSize) == 44)
614 return smb2_is_valid_lease_break(buffer);
615 else
616 return false;
617 }
618
619 cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
620
621 /* look up tcon based on tid & uid */
622 spin_lock(&cifs_tcp_ses_lock);
623 list_for_each(tmp, &server->smb_ses_list) {
624 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
625
626 list_for_each(tmp1, &ses->tcon_list) {
627 tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
628
629 spin_lock(&tcon->open_file_lock);
630 list_for_each(tmp2, &tcon->openFileList) {
631 cfile = list_entry(tmp2, struct cifsFileInfo,
632 tlist);
633 if (rsp->PersistentFid !=
634 cfile->fid.persistent_fid ||
635 rsp->VolatileFid !=
636 cfile->fid.volatile_fid)
637 continue;
638
639 cifs_dbg(FYI, "file id match, oplock break\n");
640 cifs_stats_inc(
641 &tcon->stats.cifs_stats.num_oplock_brks);
642 cinode = CIFS_I(d_inode(cfile->dentry));
643 spin_lock(&cfile->file_info_lock);
644 if (!CIFS_CACHE_WRITE(cinode) &&
645 rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
646 cfile->oplock_break_cancelled = true;
647 else
648 cfile->oplock_break_cancelled = false;
649
650 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
651 &cinode->flags);
652
653 /*
654 * Set flag if the server downgrades the oplock
655 * to L2 else clear.
656 */
657 if (rsp->OplockLevel)
658 set_bit(
659 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
660 &cinode->flags);
661 else
662 clear_bit(
663 CIFS_INODE_DOWNGRADE_OPLOCK_TO_L2,
664 &cinode->flags);
665 spin_unlock(&cfile->file_info_lock);
666
667 cifs_queue_oplock_break(cfile);
668
669 spin_unlock(&tcon->open_file_lock);
670 spin_unlock(&cifs_tcp_ses_lock);
671 return true;
672 }
673 spin_unlock(&tcon->open_file_lock);
674 }
675 }
676 spin_unlock(&cifs_tcp_ses_lock);
677 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n");
678 return false;
679 }
680
681 void
smb2_cancelled_close_fid(struct work_struct * work)682 smb2_cancelled_close_fid(struct work_struct *work)
683 {
684 struct close_cancelled_open *cancelled = container_of(work,
685 struct close_cancelled_open, work);
686
687 cifs_dbg(VFS, "Close unmatched open\n");
688
689 SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
690 cancelled->fid.volatile_fid);
691 cifs_put_tcon(cancelled->tcon);
692 kfree(cancelled);
693 }
694
695 int
smb2_handle_cancelled_mid(char * buffer,struct TCP_Server_Info * server)696 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
697 {
698 struct smb2_sync_hdr *sync_hdr = get_sync_hdr(buffer);
699 struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
700 struct cifs_tcon *tcon;
701 struct close_cancelled_open *cancelled;
702
703 if (sync_hdr->Command != SMB2_CREATE ||
704 sync_hdr->Status != STATUS_SUCCESS)
705 return 0;
706
707 cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
708 if (!cancelled)
709 return -ENOMEM;
710
711 tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
712 sync_hdr->TreeId);
713 if (!tcon) {
714 kfree(cancelled);
715 return -ENOENT;
716 }
717
718 cancelled->fid.persistent_fid = rsp->PersistentFileId;
719 cancelled->fid.volatile_fid = rsp->VolatileFileId;
720 cancelled->tcon = tcon;
721 INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
722 queue_work(cifsiod_wq, &cancelled->work);
723
724 return 0;
725 }
726