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 #include "smb2glob.h"
  32
  33 static int
  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
  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 *
 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
 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 *
 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
 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
 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
 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                          lease_state);
 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                 cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
 509                 cfile->oplock_level = lease_state;
 510
 511                 cifs_queue_oplock_break(cfile);
 512                 kfree(lw);
 513                 return true;
 514         }
 515
 516         found = false;
 517         list_for_each_entry(open, &tcon->pending_opens, olist) {
 518                 if (memcmp(open->lease_key, rsp->LeaseKey,
 519                            SMB2_LEASE_KEY_SIZE))
 520                         continue;
 521
 522                 if (!found && ack_req) {
 523                         found = true;
 524                         memcpy(lw->lease_key, open->lease_key,
 525                                SMB2_LEASE_KEY_SIZE);
 526                         lw->tlink = cifs_get_tlink(open->tlink);
 527                         queue_work(cifsiod_wq, &lw->lease_break);
 528                 }
 529
 530                 cifs_dbg(FYI, "found in the pending open list\n");
 531                 cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
 532                          lease_state);
 533
 534                 open->oplock = lease_state;
 535         }
 536         return found;
 537 }
 538
 539 static bool
 540 smb2_is_valid_lease_break(char *buffer)
 541 {
 542         struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
 543         struct list_head *tmp, *tmp1, *tmp2;
 544         struct TCP_Server_Info *server;
 545         struct cifs_ses *ses;
 546         struct cifs_tcon *tcon;
 547         struct smb2_lease_break_work *lw;
 548
 549         lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
 550         if (!lw)
 551                 return false;
 552
 553         INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
 554         lw->lease_state = rsp->NewLeaseState;
 555
 556         cifs_dbg(FYI, "Checking for lease break\n");
 557
 558         /* look up tcon based on tid & uid */
 559         spin_lock(&cifs_tcp_ses_lock);
 560         list_for_each(tmp, &cifs_tcp_ses_list) {
 561                 server = list_entry(tmp, struct TCP_Server_Info, tcp_ses_list);
 562
 563                 list_for_each(tmp1, &server->smb_ses_list) {
 564                         ses = list_entry(tmp1, struct cifs_ses, smb_ses_list);
 565
 566                         list_for_each(tmp2, &ses->tcon_list) {
 567                                 tcon = list_entry(tmp2, struct cifs_tcon,
 568                                                   tcon_list);
 569                                 spin_lock(&tcon->open_file_lock);
 570                                 cifs_stats_inc(
 571                                     &tcon->stats.cifs_stats.num_oplock_brks);
 572                                 if (smb2_tcon_has_lease(tcon, rsp, lw)) {
 573                                         spin_unlock(&tcon->open_file_lock);
 574                                         spin_unlock(&cifs_tcp_ses_lock);
 575                                         return true;
 576                                 }
 577                                 spin_unlock(&tcon->open_file_lock);
 578                         }
 579                 }
 580         }
 581         spin_unlock(&cifs_tcp_ses_lock);
 582         kfree(lw);
 583         cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
 584         return false;
 585 }
 586
 587 bool
 588 smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
 589 {
 590         struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
 591         struct list_head *tmp, *tmp1, *tmp2;
 592         struct cifs_ses *ses;
 593         struct cifs_tcon *tcon;
 594         struct cifsInodeInfo *cinode;
 595         struct cifsFileInfo *cfile;
 596
 597         cifs_dbg(FYI, "Checking for oplock break\n");
 598
 599         if (rsp->hdr.sync_hdr.Command != SMB2_OPLOCK_BREAK)
 600                 return false;
 601
 602         if (rsp->StructureSize !=
 603                                 smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
 604                 if (le16_to_cpu(rsp->StructureSize) == 44)
 605                         return smb2_is_valid_lease_break(buffer);
 606                 else
 607                         return false;
 608         }
 609
 610         cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
 611
 612         /* look up tcon based on tid & uid */
 613         spin_lock(&cifs_tcp_ses_lock);
 614         list_for_each(tmp, &server->smb_ses_list) {
 615                 ses = list_entry(tmp, struct cifs_ses, smb_ses_list);
 616
 617                 list_for_each(tmp1, &ses->tcon_list) {
 618                         tcon = list_entry(tmp1, struct cifs_tcon, tcon_list);
 619
 620                         spin_lock(&tcon->open_file_lock);
 621                         list_for_each(tmp2, &tcon->openFileList) {
 622                                 cfile = list_entry(tmp2, struct cifsFileInfo,
 623                                                      tlist);
 624                                 if (rsp->PersistentFid !=
 625                                     cfile->fid.persistent_fid ||
 626                                     rsp->VolatileFid !=
 627                                     cfile->fid.volatile_fid)
 628                                         continue;
 629
 630                                 cifs_dbg(FYI, "file id match, oplock break\n");
 631                                 cifs_stats_inc(
 632                                     &tcon->stats.cifs_stats.num_oplock_brks);
 633                                 cinode = CIFS_I(d_inode(cfile->dentry));
 634                                 spin_lock(&cfile->file_info_lock);
 635                                 if (!CIFS_CACHE_WRITE(cinode) &&
 636                                     rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
 637                                         cfile->oplock_break_cancelled = true;
 638                                 else
 639                                         cfile->oplock_break_cancelled = false;
 640
 641                                 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
 642                                         &cinode->flags);
 643
 644                                 cfile->oplock_epoch = 0;
 645                                 cfile->oplock_level = rsp->OplockLevel;
 646
 647                                 spin_unlock(&cfile->file_info_lock);
 648
 649                                 cifs_queue_oplock_break(cfile);
 650
 651                                 spin_unlock(&tcon->open_file_lock);
 652                                 spin_unlock(&cifs_tcp_ses_lock);
 653                                 return true;
 654                         }
 655                         spin_unlock(&tcon->open_file_lock);
 656                 }
 657         }
 658         spin_unlock(&cifs_tcp_ses_lock);
 659         cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
 660         return true;
 661 }
 662
 663 void
 664 smb2_cancelled_close_fid(struct work_struct *work)
 665 {
 666         struct close_cancelled_open *cancelled = container_of(work,
 667                                         struct close_cancelled_open, work);
 668
 669         cifs_dbg(VFS, "Close unmatched open\n");
 670
 671         SMB2_close(0, cancelled->tcon, cancelled->fid.persistent_fid,
 672                    cancelled->fid.volatile_fid);
 673         cifs_put_tcon(cancelled->tcon);
 674         kfree(cancelled);
 675 }
 676
 677 int
 678 smb2_handle_cancelled_mid(char *buffer, struct TCP_Server_Info *server)
 679 {
 680         struct smb2_sync_hdr *sync_hdr = get_sync_hdr(buffer);
 681         struct smb2_create_rsp *rsp = (struct smb2_create_rsp *)buffer;
 682         struct cifs_tcon *tcon;
 683         struct close_cancelled_open *cancelled;
 684
 685         if (sync_hdr->Command != SMB2_CREATE ||
 686             sync_hdr->Status != STATUS_SUCCESS)
 687                 return 0;
 688
 689         cancelled = kzalloc(sizeof(*cancelled), GFP_KERNEL);
 690         if (!cancelled)
 691                 return -ENOMEM;
 692
 693         tcon = smb2_find_smb_tcon(server, sync_hdr->SessionId,
 694                                   sync_hdr->TreeId);
 695         if (!tcon) {
 696                 kfree(cancelled);
 697                 return -ENOENT;
 698         }
 699
 700         cancelled->fid.persistent_fid = rsp->PersistentFileId;
 701         cancelled->fid.volatile_fid = rsp->VolatileFileId;
 702         cancelled->tcon = tcon;
 703         INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
 704         queue_work(cifsiod_wq, &cancelled->work);
 705
 706         return 0;
 707 }