1 // SPDX-License-Identifier: LGPL-2.1 2 /* 3 * 4 * Copyright (C) International Business Machines Corp., 2002,2008 5 * Author(s): Steve French (sfrench@us.ibm.com) 6 * 7 */ 8 9 #include <linux/slab.h> 10 #include <linux/ctype.h> 11 #include <linux/mempool.h> 12 #include <linux/vmalloc.h> 13 #include "cifspdu.h" 14 #include "cifsglob.h" 15 #include "cifsproto.h" 16 #include "cifs_debug.h" 17 #include "smberr.h" 18 #include "nterr.h" 19 #include "cifs_unicode.h" 20 #include "smb2pdu.h" 21 #include "cifsfs.h" 22 #ifdef CONFIG_CIFS_DFS_UPCALL 23 #include "dns_resolve.h" 24 #include "dfs_cache.h" 25 #include "dfs.h" 26 #endif 27 #include "fs_context.h" 28 #include "cached_dir.h" 29 30 extern mempool_t *cifs_sm_req_poolp; 31 extern mempool_t *cifs_req_poolp; 32 33 /* The xid serves as a useful identifier for each incoming vfs request, 34 in a similar way to the mid which is useful to track each sent smb, 35 and CurrentXid can also provide a running counter (although it 36 will eventually wrap past zero) of the total vfs operations handled 37 since the cifs fs was mounted */ 38 39 unsigned int 40 _get_xid(void) 41 { 42 unsigned int xid; 43 44 spin_lock(&GlobalMid_Lock); 45 GlobalTotalActiveXid++; 46 47 /* keep high water mark for number of simultaneous ops in filesystem */ 48 if (GlobalTotalActiveXid > GlobalMaxActiveXid) 49 GlobalMaxActiveXid = GlobalTotalActiveXid; 50 if (GlobalTotalActiveXid > 65000) 51 cifs_dbg(FYI, "warning: more than 65000 requests active\n"); 52 xid = GlobalCurrentXid++; 53 spin_unlock(&GlobalMid_Lock); 54 return xid; 55 } 56 57 void 58 _free_xid(unsigned int xid) 59 { 60 spin_lock(&GlobalMid_Lock); 61 /* if (GlobalTotalActiveXid == 0) 62 BUG(); */ 63 GlobalTotalActiveXid--; 64 spin_unlock(&GlobalMid_Lock); 65 } 66 67 struct cifs_ses * 68 sesInfoAlloc(void) 69 { 70 struct cifs_ses *ret_buf; 71 72 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL); 73 if (ret_buf) { 74 atomic_inc(&sesInfoAllocCount); 75 spin_lock_init(&ret_buf->ses_lock); 76 ret_buf->ses_status = SES_NEW; 77 ++ret_buf->ses_count; 78 INIT_LIST_HEAD(&ret_buf->smb_ses_list); 79 INIT_LIST_HEAD(&ret_buf->tcon_list); 80 mutex_init(&ret_buf->session_mutex); 81 spin_lock_init(&ret_buf->iface_lock); 82 INIT_LIST_HEAD(&ret_buf->iface_list); 83 spin_lock_init(&ret_buf->chan_lock); 84 } 85 return ret_buf; 86 } 87 88 void 89 sesInfoFree(struct cifs_ses *buf_to_free) 90 { 91 struct cifs_server_iface *iface = NULL, *niface = NULL; 92 93 if (buf_to_free == NULL) { 94 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n"); 95 return; 96 } 97 98 unload_nls(buf_to_free->local_nls); 99 atomic_dec(&sesInfoAllocCount); 100 kfree(buf_to_free->serverOS); 101 kfree(buf_to_free->serverDomain); 102 kfree(buf_to_free->serverNOS); 103 kfree_sensitive(buf_to_free->password); 104 kfree(buf_to_free->user_name); 105 kfree(buf_to_free->domainName); 106 kfree_sensitive(buf_to_free->auth_key.response); 107 spin_lock(&buf_to_free->iface_lock); 108 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list, 109 iface_head) 110 kref_put(&iface->refcount, release_iface); 111 spin_unlock(&buf_to_free->iface_lock); 112 kfree_sensitive(buf_to_free); 113 } 114 115 struct cifs_tcon * 116 tcon_info_alloc(bool dir_leases_enabled) 117 { 118 struct cifs_tcon *ret_buf; 119 120 ret_buf = kzalloc(sizeof(*ret_buf), GFP_KERNEL); 121 if (!ret_buf) 122 return NULL; 123 124 if (dir_leases_enabled == true) { 125 ret_buf->cfids = init_cached_dirs(); 126 if (!ret_buf->cfids) { 127 kfree(ret_buf); 128 return NULL; 129 } 130 } 131 /* else ret_buf->cfids is already set to NULL above */ 132 133 atomic_inc(&tconInfoAllocCount); 134 ret_buf->status = TID_NEW; 135 ++ret_buf->tc_count; 136 spin_lock_init(&ret_buf->tc_lock); 137 INIT_LIST_HEAD(&ret_buf->openFileList); 138 INIT_LIST_HEAD(&ret_buf->tcon_list); 139 spin_lock_init(&ret_buf->open_file_lock); 140 spin_lock_init(&ret_buf->stat_lock); 141 atomic_set(&ret_buf->num_local_opens, 0); 142 atomic_set(&ret_buf->num_remote_opens, 0); 143 #ifdef CONFIG_CIFS_DFS_UPCALL 144 INIT_LIST_HEAD(&ret_buf->dfs_ses_list); 145 #endif 146 147 return ret_buf; 148 } 149 150 void 151 tconInfoFree(struct cifs_tcon *tcon) 152 { 153 if (tcon == NULL) { 154 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n"); 155 return; 156 } 157 free_cached_dirs(tcon->cfids); 158 atomic_dec(&tconInfoAllocCount); 159 kfree(tcon->nativeFileSystem); 160 kfree_sensitive(tcon->password); 161 #ifdef CONFIG_CIFS_DFS_UPCALL 162 dfs_put_root_smb_sessions(&tcon->dfs_ses_list); 163 #endif 164 kfree(tcon->origin_fullpath); 165 kfree(tcon); 166 } 167 168 struct smb_hdr * 169 cifs_buf_get(void) 170 { 171 struct smb_hdr *ret_buf = NULL; 172 /* 173 * SMB2 header is bigger than CIFS one - no problems to clean some 174 * more bytes for CIFS. 175 */ 176 size_t buf_size = sizeof(struct smb2_hdr); 177 178 /* 179 * We could use negotiated size instead of max_msgsize - 180 * but it may be more efficient to always alloc same size 181 * albeit slightly larger than necessary and maxbuffersize 182 * defaults to this and can not be bigger. 183 */ 184 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS); 185 186 /* clear the first few header bytes */ 187 /* for most paths, more is cleared in header_assemble */ 188 memset(ret_buf, 0, buf_size + 3); 189 atomic_inc(&buf_alloc_count); 190 #ifdef CONFIG_CIFS_STATS2 191 atomic_inc(&total_buf_alloc_count); 192 #endif /* CONFIG_CIFS_STATS2 */ 193 194 return ret_buf; 195 } 196 197 void 198 cifs_buf_release(void *buf_to_free) 199 { 200 if (buf_to_free == NULL) { 201 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/ 202 return; 203 } 204 mempool_free(buf_to_free, cifs_req_poolp); 205 206 atomic_dec(&buf_alloc_count); 207 return; 208 } 209 210 struct smb_hdr * 211 cifs_small_buf_get(void) 212 { 213 struct smb_hdr *ret_buf = NULL; 214 215 /* We could use negotiated size instead of max_msgsize - 216 but it may be more efficient to always alloc same size 217 albeit slightly larger than necessary and maxbuffersize 218 defaults to this and can not be bigger */ 219 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS); 220 /* No need to clear memory here, cleared in header assemble */ 221 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/ 222 atomic_inc(&small_buf_alloc_count); 223 #ifdef CONFIG_CIFS_STATS2 224 atomic_inc(&total_small_buf_alloc_count); 225 #endif /* CONFIG_CIFS_STATS2 */ 226 227 return ret_buf; 228 } 229 230 void 231 cifs_small_buf_release(void *buf_to_free) 232 { 233 234 if (buf_to_free == NULL) { 235 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n"); 236 return; 237 } 238 mempool_free(buf_to_free, cifs_sm_req_poolp); 239 240 atomic_dec(&small_buf_alloc_count); 241 return; 242 } 243 244 void 245 free_rsp_buf(int resp_buftype, void *rsp) 246 { 247 if (resp_buftype == CIFS_SMALL_BUFFER) 248 cifs_small_buf_release(rsp); 249 else if (resp_buftype == CIFS_LARGE_BUFFER) 250 cifs_buf_release(rsp); 251 } 252 253 /* NB: MID can not be set if treeCon not passed in, in that 254 case it is responsbility of caller to set the mid */ 255 void 256 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ , 257 const struct cifs_tcon *treeCon, int word_count 258 /* length of fixed section (word count) in two byte units */) 259 { 260 char *temp = (char *) buffer; 261 262 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */ 263 264 buffer->smb_buf_length = cpu_to_be32( 265 (2 * word_count) + sizeof(struct smb_hdr) - 266 4 /* RFC 1001 length field does not count */ + 267 2 /* for bcc field itself */) ; 268 269 buffer->Protocol[0] = 0xFF; 270 buffer->Protocol[1] = 'S'; 271 buffer->Protocol[2] = 'M'; 272 buffer->Protocol[3] = 'B'; 273 buffer->Command = smb_command; 274 buffer->Flags = 0x00; /* case sensitive */ 275 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES; 276 buffer->Pid = cpu_to_le16((__u16)current->tgid); 277 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16)); 278 if (treeCon) { 279 buffer->Tid = treeCon->tid; 280 if (treeCon->ses) { 281 if (treeCon->ses->capabilities & CAP_UNICODE) 282 buffer->Flags2 |= SMBFLG2_UNICODE; 283 if (treeCon->ses->capabilities & CAP_STATUS32) 284 buffer->Flags2 |= SMBFLG2_ERR_STATUS; 285 286 /* Uid is not converted */ 287 buffer->Uid = treeCon->ses->Suid; 288 if (treeCon->ses->server) 289 buffer->Mid = get_next_mid(treeCon->ses->server); 290 } 291 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS) 292 buffer->Flags2 |= SMBFLG2_DFS; 293 if (treeCon->nocase) 294 buffer->Flags |= SMBFLG_CASELESS; 295 if ((treeCon->ses) && (treeCon->ses->server)) 296 if (treeCon->ses->server->sign) 297 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; 298 } 299 300 /* endian conversion of flags is now done just before sending */ 301 buffer->WordCount = (char) word_count; 302 return; 303 } 304 305 static int 306 check_smb_hdr(struct smb_hdr *smb) 307 { 308 /* does it have the right SMB "signature" ? */ 309 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) { 310 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n", 311 *(unsigned int *)smb->Protocol); 312 return 1; 313 } 314 315 /* if it's a response then accept */ 316 if (smb->Flags & SMBFLG_RESPONSE) 317 return 0; 318 319 /* only one valid case where server sends us request */ 320 if (smb->Command == SMB_COM_LOCKING_ANDX) 321 return 0; 322 323 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n", 324 get_mid(smb)); 325 return 1; 326 } 327 328 int 329 checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server) 330 { 331 struct smb_hdr *smb = (struct smb_hdr *)buf; 332 __u32 rfclen = be32_to_cpu(smb->smb_buf_length); 333 __u32 clc_len; /* calculated length */ 334 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n", 335 total_read, rfclen); 336 337 /* is this frame too small to even get to a BCC? */ 338 if (total_read < 2 + sizeof(struct smb_hdr)) { 339 if ((total_read >= sizeof(struct smb_hdr) - 1) 340 && (smb->Status.CifsError != 0)) { 341 /* it's an error return */ 342 smb->WordCount = 0; 343 /* some error cases do not return wct and bcc */ 344 return 0; 345 } else if ((total_read == sizeof(struct smb_hdr) + 1) && 346 (smb->WordCount == 0)) { 347 char *tmp = (char *)smb; 348 /* Need to work around a bug in two servers here */ 349 /* First, check if the part of bcc they sent was zero */ 350 if (tmp[sizeof(struct smb_hdr)] == 0) { 351 /* some servers return only half of bcc 352 * on simple responses (wct, bcc both zero) 353 * in particular have seen this on 354 * ulogoffX and FindClose. This leaves 355 * one byte of bcc potentially unitialized 356 */ 357 /* zero rest of bcc */ 358 tmp[sizeof(struct smb_hdr)+1] = 0; 359 return 0; 360 } 361 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n"); 362 } else { 363 cifs_dbg(VFS, "Length less than smb header size\n"); 364 } 365 return -EIO; 366 } 367 368 /* otherwise, there is enough to get to the BCC */ 369 if (check_smb_hdr(smb)) 370 return -EIO; 371 clc_len = smbCalcSize(smb); 372 373 if (4 + rfclen != total_read) { 374 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n", 375 rfclen); 376 return -EIO; 377 } 378 379 if (4 + rfclen != clc_len) { 380 __u16 mid = get_mid(smb); 381 /* check if bcc wrapped around for large read responses */ 382 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) { 383 /* check if lengths match mod 64K */ 384 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF)) 385 return 0; /* bcc wrapped */ 386 } 387 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n", 388 clc_len, 4 + rfclen, mid); 389 390 if (4 + rfclen < clc_len) { 391 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n", 392 rfclen, mid); 393 return -EIO; 394 } else if (rfclen > clc_len + 512) { 395 /* 396 * Some servers (Windows XP in particular) send more 397 * data than the lengths in the SMB packet would 398 * indicate on certain calls (byte range locks and 399 * trans2 find first calls in particular). While the 400 * client can handle such a frame by ignoring the 401 * trailing data, we choose limit the amount of extra 402 * data to 512 bytes. 403 */ 404 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n", 405 rfclen, mid); 406 return -EIO; 407 } 408 } 409 return 0; 410 } 411 412 bool 413 is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv) 414 { 415 struct smb_hdr *buf = (struct smb_hdr *)buffer; 416 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf; 417 struct TCP_Server_Info *pserver; 418 struct cifs_ses *ses; 419 struct cifs_tcon *tcon; 420 struct cifsInodeInfo *pCifsInode; 421 struct cifsFileInfo *netfile; 422 423 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n"); 424 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) && 425 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) { 426 struct smb_com_transaction_change_notify_rsp *pSMBr = 427 (struct smb_com_transaction_change_notify_rsp *)buf; 428 struct file_notify_information *pnotify; 429 __u32 data_offset = 0; 430 size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length); 431 432 if (get_bcc(buf) > sizeof(struct file_notify_information)) { 433 data_offset = le32_to_cpu(pSMBr->DataOffset); 434 435 if (data_offset > 436 len - sizeof(struct file_notify_information)) { 437 cifs_dbg(FYI, "Invalid data_offset %u\n", 438 data_offset); 439 return true; 440 } 441 pnotify = (struct file_notify_information *) 442 ((char *)&pSMBr->hdr.Protocol + data_offset); 443 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n", 444 pnotify->FileName, pnotify->Action); 445 /* cifs_dump_mem("Rcvd notify Data: ",buf, 446 sizeof(struct smb_hdr)+60); */ 447 return true; 448 } 449 if (pSMBr->hdr.Status.CifsError) { 450 cifs_dbg(FYI, "notify err 0x%x\n", 451 pSMBr->hdr.Status.CifsError); 452 return true; 453 } 454 return false; 455 } 456 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX) 457 return false; 458 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) { 459 /* no sense logging error on invalid handle on oplock 460 break - harmless race between close request and oplock 461 break response is expected from time to time writing out 462 large dirty files cached on the client */ 463 if ((NT_STATUS_INVALID_HANDLE) == 464 le32_to_cpu(pSMB->hdr.Status.CifsError)) { 465 cifs_dbg(FYI, "Invalid handle on oplock break\n"); 466 return true; 467 } else if (ERRbadfid == 468 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) { 469 return true; 470 } else { 471 return false; /* on valid oplock brk we get "request" */ 472 } 473 } 474 if (pSMB->hdr.WordCount != 8) 475 return false; 476 477 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n", 478 pSMB->LockType, pSMB->OplockLevel); 479 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)) 480 return false; 481 482 /* If server is a channel, select the primary channel */ 483 pserver = SERVER_IS_CHAN(srv) ? srv->primary_server : srv; 484 485 /* look up tcon based on tid & uid */ 486 spin_lock(&cifs_tcp_ses_lock); 487 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) { 488 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) { 489 if (tcon->tid != buf->Tid) 490 continue; 491 492 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks); 493 spin_lock(&tcon->open_file_lock); 494 list_for_each_entry(netfile, &tcon->openFileList, tlist) { 495 if (pSMB->Fid != netfile->fid.netfid) 496 continue; 497 498 cifs_dbg(FYI, "file id match, oplock break\n"); 499 pCifsInode = CIFS_I(d_inode(netfile->dentry)); 500 501 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, 502 &pCifsInode->flags); 503 504 netfile->oplock_epoch = 0; 505 netfile->oplock_level = pSMB->OplockLevel; 506 netfile->oplock_break_cancelled = false; 507 cifs_queue_oplock_break(netfile); 508 509 spin_unlock(&tcon->open_file_lock); 510 spin_unlock(&cifs_tcp_ses_lock); 511 return true; 512 } 513 spin_unlock(&tcon->open_file_lock); 514 spin_unlock(&cifs_tcp_ses_lock); 515 cifs_dbg(FYI, "No matching file for oplock break\n"); 516 return true; 517 } 518 } 519 spin_unlock(&cifs_tcp_ses_lock); 520 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n"); 521 return true; 522 } 523 524 void 525 dump_smb(void *buf, int smb_buf_length) 526 { 527 if (traceSMB == 0) 528 return; 529 530 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf, 531 smb_buf_length, true); 532 } 533 534 void 535 cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb) 536 { 537 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { 538 struct cifs_tcon *tcon = NULL; 539 540 if (cifs_sb->master_tlink) 541 tcon = cifs_sb_master_tcon(cifs_sb); 542 543 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; 544 cifs_sb->mnt_cifs_serverino_autodisabled = true; 545 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n", 546 tcon ? tcon->tree_name : "new server"); 547 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n"); 548 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n"); 549 550 } 551 } 552 553 void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock) 554 { 555 oplock &= 0xF; 556 557 if (oplock == OPLOCK_EXCLUSIVE) { 558 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG; 559 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n", 560 &cinode->netfs.inode); 561 } else if (oplock == OPLOCK_READ) { 562 cinode->oplock = CIFS_CACHE_READ_FLG; 563 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n", 564 &cinode->netfs.inode); 565 } else 566 cinode->oplock = 0; 567 } 568 569 /* 570 * We wait for oplock breaks to be processed before we attempt to perform 571 * writes. 572 */ 573 int cifs_get_writer(struct cifsInodeInfo *cinode) 574 { 575 int rc; 576 577 start: 578 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK, 579 TASK_KILLABLE); 580 if (rc) 581 return rc; 582 583 spin_lock(&cinode->writers_lock); 584 if (!cinode->writers) 585 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 586 cinode->writers++; 587 /* Check to see if we have started servicing an oplock break */ 588 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) { 589 cinode->writers--; 590 if (cinode->writers == 0) { 591 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 592 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 593 } 594 spin_unlock(&cinode->writers_lock); 595 goto start; 596 } 597 spin_unlock(&cinode->writers_lock); 598 return 0; 599 } 600 601 void cifs_put_writer(struct cifsInodeInfo *cinode) 602 { 603 spin_lock(&cinode->writers_lock); 604 cinode->writers--; 605 if (cinode->writers == 0) { 606 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 607 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 608 } 609 spin_unlock(&cinode->writers_lock); 610 } 611 612 /** 613 * cifs_queue_oplock_break - queue the oplock break handler for cfile 614 * @cfile: The file to break the oplock on 615 * 616 * This function is called from the demultiplex thread when it 617 * receives an oplock break for @cfile. 618 * 619 * Assumes the tcon->open_file_lock is held. 620 * Assumes cfile->file_info_lock is NOT held. 621 */ 622 void cifs_queue_oplock_break(struct cifsFileInfo *cfile) 623 { 624 /* 625 * Bump the handle refcount now while we hold the 626 * open_file_lock to enforce the validity of it for the oplock 627 * break handler. The matching put is done at the end of the 628 * handler. 629 */ 630 cifsFileInfo_get(cfile); 631 632 queue_work(cifsoplockd_wq, &cfile->oplock_break); 633 } 634 635 void cifs_done_oplock_break(struct cifsInodeInfo *cinode) 636 { 637 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags); 638 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK); 639 } 640 641 bool 642 backup_cred(struct cifs_sb_info *cifs_sb) 643 { 644 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) { 645 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid())) 646 return true; 647 } 648 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) { 649 if (in_group_p(cifs_sb->ctx->backupgid)) 650 return true; 651 } 652 653 return false; 654 } 655 656 void 657 cifs_del_pending_open(struct cifs_pending_open *open) 658 { 659 spin_lock(&tlink_tcon(open->tlink)->open_file_lock); 660 list_del(&open->olist); 661 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 662 } 663 664 void 665 cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink, 666 struct cifs_pending_open *open) 667 { 668 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE); 669 open->oplock = CIFS_OPLOCK_NO_CHANGE; 670 open->tlink = tlink; 671 fid->pending_open = open; 672 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens); 673 } 674 675 void 676 cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink, 677 struct cifs_pending_open *open) 678 { 679 spin_lock(&tlink_tcon(tlink)->open_file_lock); 680 cifs_add_pending_open_locked(fid, tlink, open); 681 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 682 } 683 684 /* 685 * Critical section which runs after acquiring deferred_lock. 686 * As there is no reference count on cifs_deferred_close, pdclose 687 * should not be used outside deferred_lock. 688 */ 689 bool 690 cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose) 691 { 692 struct cifs_deferred_close *dclose; 693 694 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) { 695 if ((dclose->netfid == cfile->fid.netfid) && 696 (dclose->persistent_fid == cfile->fid.persistent_fid) && 697 (dclose->volatile_fid == cfile->fid.volatile_fid)) { 698 *pdclose = dclose; 699 return true; 700 } 701 } 702 return false; 703 } 704 705 /* 706 * Critical section which runs after acquiring deferred_lock. 707 */ 708 void 709 cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose) 710 { 711 bool is_deferred = false; 712 struct cifs_deferred_close *pdclose; 713 714 is_deferred = cifs_is_deferred_close(cfile, &pdclose); 715 if (is_deferred) { 716 kfree(dclose); 717 return; 718 } 719 720 dclose->tlink = cfile->tlink; 721 dclose->netfid = cfile->fid.netfid; 722 dclose->persistent_fid = cfile->fid.persistent_fid; 723 dclose->volatile_fid = cfile->fid.volatile_fid; 724 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes); 725 } 726 727 /* 728 * Critical section which runs after acquiring deferred_lock. 729 */ 730 void 731 cifs_del_deferred_close(struct cifsFileInfo *cfile) 732 { 733 bool is_deferred = false; 734 struct cifs_deferred_close *dclose; 735 736 is_deferred = cifs_is_deferred_close(cfile, &dclose); 737 if (!is_deferred) 738 return; 739 list_del(&dclose->dlist); 740 kfree(dclose); 741 } 742 743 void 744 cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode) 745 { 746 struct cifsFileInfo *cfile = NULL; 747 struct file_list *tmp_list, *tmp_next_list; 748 struct list_head file_head; 749 750 if (cifs_inode == NULL) 751 return; 752 753 INIT_LIST_HEAD(&file_head); 754 spin_lock(&cifs_inode->open_file_lock); 755 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) { 756 if (delayed_work_pending(&cfile->deferred)) { 757 if (cancel_delayed_work(&cfile->deferred)) { 758 spin_lock(&cifs_inode->deferred_lock); 759 cifs_del_deferred_close(cfile); 760 spin_unlock(&cifs_inode->deferred_lock); 761 762 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 763 if (tmp_list == NULL) 764 break; 765 tmp_list->cfile = cfile; 766 list_add_tail(&tmp_list->list, &file_head); 767 } 768 } 769 } 770 spin_unlock(&cifs_inode->open_file_lock); 771 772 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 773 _cifsFileInfo_put(tmp_list->cfile, false, false); 774 list_del(&tmp_list->list); 775 kfree(tmp_list); 776 } 777 } 778 779 void 780 cifs_close_all_deferred_files(struct cifs_tcon *tcon) 781 { 782 struct cifsFileInfo *cfile; 783 struct file_list *tmp_list, *tmp_next_list; 784 struct list_head file_head; 785 786 INIT_LIST_HEAD(&file_head); 787 spin_lock(&tcon->open_file_lock); 788 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 789 if (delayed_work_pending(&cfile->deferred)) { 790 if (cancel_delayed_work(&cfile->deferred)) { 791 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 792 cifs_del_deferred_close(cfile); 793 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 794 795 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 796 if (tmp_list == NULL) 797 break; 798 tmp_list->cfile = cfile; 799 list_add_tail(&tmp_list->list, &file_head); 800 } 801 } 802 } 803 spin_unlock(&tcon->open_file_lock); 804 805 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 806 _cifsFileInfo_put(tmp_list->cfile, true, false); 807 list_del(&tmp_list->list); 808 kfree(tmp_list); 809 } 810 } 811 void 812 cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path) 813 { 814 struct cifsFileInfo *cfile; 815 struct file_list *tmp_list, *tmp_next_list; 816 struct list_head file_head; 817 void *page; 818 const char *full_path; 819 820 INIT_LIST_HEAD(&file_head); 821 page = alloc_dentry_path(); 822 spin_lock(&tcon->open_file_lock); 823 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 824 full_path = build_path_from_dentry(cfile->dentry, page); 825 if (strstr(full_path, path)) { 826 if (delayed_work_pending(&cfile->deferred)) { 827 if (cancel_delayed_work(&cfile->deferred)) { 828 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 829 cifs_del_deferred_close(cfile); 830 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 831 832 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 833 if (tmp_list == NULL) 834 break; 835 tmp_list->cfile = cfile; 836 list_add_tail(&tmp_list->list, &file_head); 837 } 838 } 839 } 840 } 841 spin_unlock(&tcon->open_file_lock); 842 843 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 844 _cifsFileInfo_put(tmp_list->cfile, true, false); 845 list_del(&tmp_list->list); 846 kfree(tmp_list); 847 } 848 free_dentry_path(page); 849 } 850 851 /* parses DFS referral V3 structure 852 * caller is responsible for freeing target_nodes 853 * returns: 854 * - on success - 0 855 * - on failure - errno 856 */ 857 int 858 parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size, 859 unsigned int *num_of_nodes, 860 struct dfs_info3_param **target_nodes, 861 const struct nls_table *nls_codepage, int remap, 862 const char *searchName, bool is_unicode) 863 { 864 int i, rc = 0; 865 char *data_end; 866 struct dfs_referral_level_3 *ref; 867 868 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals); 869 870 if (*num_of_nodes < 1) { 871 cifs_dbg(VFS, "num_referrals: must be at least > 0, but we get num_referrals = %d\n", 872 *num_of_nodes); 873 rc = -EINVAL; 874 goto parse_DFS_referrals_exit; 875 } 876 877 ref = (struct dfs_referral_level_3 *) &(rsp->referrals); 878 if (ref->VersionNumber != cpu_to_le16(3)) { 879 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n", 880 le16_to_cpu(ref->VersionNumber)); 881 rc = -EINVAL; 882 goto parse_DFS_referrals_exit; 883 } 884 885 /* get the upper boundary of the resp buffer */ 886 data_end = (char *)rsp + rsp_size; 887 888 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n", 889 *num_of_nodes, le32_to_cpu(rsp->DFSFlags)); 890 891 *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param), 892 GFP_KERNEL); 893 if (*target_nodes == NULL) { 894 rc = -ENOMEM; 895 goto parse_DFS_referrals_exit; 896 } 897 898 /* collect necessary data from referrals */ 899 for (i = 0; i < *num_of_nodes; i++) { 900 char *temp; 901 int max_len; 902 struct dfs_info3_param *node = (*target_nodes)+i; 903 904 node->flags = le32_to_cpu(rsp->DFSFlags); 905 if (is_unicode) { 906 __le16 *tmp = kmalloc(strlen(searchName)*2 + 2, 907 GFP_KERNEL); 908 if (tmp == NULL) { 909 rc = -ENOMEM; 910 goto parse_DFS_referrals_exit; 911 } 912 cifsConvertToUTF16((__le16 *) tmp, searchName, 913 PATH_MAX, nls_codepage, remap); 914 node->path_consumed = cifs_utf16_bytes(tmp, 915 le16_to_cpu(rsp->PathConsumed), 916 nls_codepage); 917 kfree(tmp); 918 } else 919 node->path_consumed = le16_to_cpu(rsp->PathConsumed); 920 921 node->server_type = le16_to_cpu(ref->ServerType); 922 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags); 923 924 /* copy DfsPath */ 925 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset); 926 max_len = data_end - temp; 927 node->path_name = cifs_strndup_from_utf16(temp, max_len, 928 is_unicode, nls_codepage); 929 if (!node->path_name) { 930 rc = -ENOMEM; 931 goto parse_DFS_referrals_exit; 932 } 933 934 /* copy link target UNC */ 935 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset); 936 max_len = data_end - temp; 937 node->node_name = cifs_strndup_from_utf16(temp, max_len, 938 is_unicode, nls_codepage); 939 if (!node->node_name) { 940 rc = -ENOMEM; 941 goto parse_DFS_referrals_exit; 942 } 943 944 node->ttl = le32_to_cpu(ref->TimeToLive); 945 946 ref++; 947 } 948 949 parse_DFS_referrals_exit: 950 if (rc) { 951 free_dfs_info_array(*target_nodes, *num_of_nodes); 952 *target_nodes = NULL; 953 *num_of_nodes = 0; 954 } 955 return rc; 956 } 957 958 struct cifs_aio_ctx * 959 cifs_aio_ctx_alloc(void) 960 { 961 struct cifs_aio_ctx *ctx; 962 963 /* 964 * Must use kzalloc to initialize ctx->bv to NULL and ctx->direct_io 965 * to false so that we know when we have to unreference pages within 966 * cifs_aio_ctx_release() 967 */ 968 ctx = kzalloc(sizeof(struct cifs_aio_ctx), GFP_KERNEL); 969 if (!ctx) 970 return NULL; 971 972 INIT_LIST_HEAD(&ctx->list); 973 mutex_init(&ctx->aio_mutex); 974 init_completion(&ctx->done); 975 kref_init(&ctx->refcount); 976 return ctx; 977 } 978 979 void 980 cifs_aio_ctx_release(struct kref *refcount) 981 { 982 struct cifs_aio_ctx *ctx = container_of(refcount, 983 struct cifs_aio_ctx, refcount); 984 985 cifsFileInfo_put(ctx->cfile); 986 987 /* 988 * ctx->bv is only set if setup_aio_ctx_iter() was call successfuly 989 * which means that iov_iter_extract_pages() was a success and thus 990 * that we may have references or pins on pages that we need to 991 * release. 992 */ 993 if (ctx->bv) { 994 if (ctx->should_dirty || ctx->bv_need_unpin) { 995 unsigned int i; 996 997 for (i = 0; i < ctx->nr_pinned_pages; i++) { 998 struct page *page = ctx->bv[i].bv_page; 999 1000 if (ctx->should_dirty) 1001 set_page_dirty(page); 1002 if (ctx->bv_need_unpin) 1003 unpin_user_page(page); 1004 } 1005 } 1006 kvfree(ctx->bv); 1007 } 1008 1009 kfree(ctx); 1010 } 1011 1012 /** 1013 * cifs_alloc_hash - allocate hash and hash context together 1014 * @name: The name of the crypto hash algo 1015 * @sdesc: SHASH descriptor where to put the pointer to the hash TFM 1016 * 1017 * The caller has to make sure @sdesc is initialized to either NULL or 1018 * a valid context. It can be freed via cifs_free_hash(). 1019 */ 1020 int 1021 cifs_alloc_hash(const char *name, struct shash_desc **sdesc) 1022 { 1023 int rc = 0; 1024 struct crypto_shash *alg = NULL; 1025 1026 if (*sdesc) 1027 return 0; 1028 1029 alg = crypto_alloc_shash(name, 0, 0); 1030 if (IS_ERR(alg)) { 1031 cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name); 1032 rc = PTR_ERR(alg); 1033 *sdesc = NULL; 1034 return rc; 1035 } 1036 1037 *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL); 1038 if (*sdesc == NULL) { 1039 cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name); 1040 crypto_free_shash(alg); 1041 return -ENOMEM; 1042 } 1043 1044 (*sdesc)->tfm = alg; 1045 return 0; 1046 } 1047 1048 /** 1049 * cifs_free_hash - free hash and hash context together 1050 * @sdesc: Where to find the pointer to the hash TFM 1051 * 1052 * Freeing a NULL descriptor is safe. 1053 */ 1054 void 1055 cifs_free_hash(struct shash_desc **sdesc) 1056 { 1057 if (unlikely(!sdesc) || !*sdesc) 1058 return; 1059 1060 if ((*sdesc)->tfm) { 1061 crypto_free_shash((*sdesc)->tfm); 1062 (*sdesc)->tfm = NULL; 1063 } 1064 1065 kfree_sensitive(*sdesc); 1066 *sdesc = NULL; 1067 } 1068 1069 void extract_unc_hostname(const char *unc, const char **h, size_t *len) 1070 { 1071 const char *end; 1072 1073 /* skip initial slashes */ 1074 while (*unc && (*unc == '\\' || *unc == '/')) 1075 unc++; 1076 1077 end = unc; 1078 1079 while (*end && !(*end == '\\' || *end == '/')) 1080 end++; 1081 1082 *h = unc; 1083 *len = end - unc; 1084 } 1085 1086 /** 1087 * copy_path_name - copy src path to dst, possibly truncating 1088 * @dst: The destination buffer 1089 * @src: The source name 1090 * 1091 * returns number of bytes written (including trailing nul) 1092 */ 1093 int copy_path_name(char *dst, const char *src) 1094 { 1095 int name_len; 1096 1097 /* 1098 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it 1099 * will truncate and strlen(dst) will be PATH_MAX-1 1100 */ 1101 name_len = strscpy(dst, src, PATH_MAX); 1102 if (WARN_ON_ONCE(name_len < 0)) 1103 name_len = PATH_MAX-1; 1104 1105 /* we count the trailing nul */ 1106 name_len++; 1107 return name_len; 1108 } 1109 1110 struct super_cb_data { 1111 void *data; 1112 struct super_block *sb; 1113 }; 1114 1115 static void tcon_super_cb(struct super_block *sb, void *arg) 1116 { 1117 struct super_cb_data *sd = arg; 1118 struct cifs_sb_info *cifs_sb; 1119 struct cifs_tcon *t1 = sd->data, *t2; 1120 1121 if (sd->sb) 1122 return; 1123 1124 cifs_sb = CIFS_SB(sb); 1125 t2 = cifs_sb_master_tcon(cifs_sb); 1126 1127 spin_lock(&t2->tc_lock); 1128 if (t1->ses == t2->ses && 1129 t1->ses->server == t2->ses->server && 1130 t2->origin_fullpath && 1131 dfs_src_pathname_equal(t2->origin_fullpath, t1->origin_fullpath)) 1132 sd->sb = sb; 1133 spin_unlock(&t2->tc_lock); 1134 } 1135 1136 static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *), 1137 void *data) 1138 { 1139 struct super_cb_data sd = { 1140 .data = data, 1141 .sb = NULL, 1142 }; 1143 struct file_system_type **fs_type = (struct file_system_type *[]) { 1144 &cifs_fs_type, &smb3_fs_type, NULL, 1145 }; 1146 1147 for (; *fs_type; fs_type++) { 1148 iterate_supers_type(*fs_type, f, &sd); 1149 if (sd.sb) { 1150 /* 1151 * Grab an active reference in order to prevent automounts (DFS links) 1152 * of expiring and then freeing up our cifs superblock pointer while 1153 * we're doing failover. 1154 */ 1155 cifs_sb_active(sd.sb); 1156 return sd.sb; 1157 } 1158 } 1159 pr_warn_once("%s: could not find dfs superblock\n", __func__); 1160 return ERR_PTR(-EINVAL); 1161 } 1162 1163 static void __cifs_put_super(struct super_block *sb) 1164 { 1165 if (!IS_ERR_OR_NULL(sb)) 1166 cifs_sb_deactive(sb); 1167 } 1168 1169 struct super_block *cifs_get_dfs_tcon_super(struct cifs_tcon *tcon) 1170 { 1171 spin_lock(&tcon->tc_lock); 1172 if (!tcon->origin_fullpath) { 1173 spin_unlock(&tcon->tc_lock); 1174 return ERR_PTR(-ENOENT); 1175 } 1176 spin_unlock(&tcon->tc_lock); 1177 return __cifs_get_super(tcon_super_cb, tcon); 1178 } 1179 1180 void cifs_put_tcp_super(struct super_block *sb) 1181 { 1182 __cifs_put_super(sb); 1183 } 1184 1185 #ifdef CONFIG_CIFS_DFS_UPCALL 1186 int match_target_ip(struct TCP_Server_Info *server, 1187 const char *share, size_t share_len, 1188 bool *result) 1189 { 1190 int rc; 1191 char *target; 1192 struct sockaddr_storage ss; 1193 1194 *result = false; 1195 1196 target = kzalloc(share_len + 3, GFP_KERNEL); 1197 if (!target) 1198 return -ENOMEM; 1199 1200 scnprintf(target, share_len + 3, "\\\\%.*s", (int)share_len, share); 1201 1202 cifs_dbg(FYI, "%s: target name: %s\n", __func__, target + 2); 1203 1204 rc = dns_resolve_server_name_to_ip(target, (struct sockaddr *)&ss, NULL); 1205 kfree(target); 1206 1207 if (rc < 0) 1208 return rc; 1209 1210 spin_lock(&server->srv_lock); 1211 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss); 1212 spin_unlock(&server->srv_lock); 1213 cifs_dbg(FYI, "%s: ip addresses match: %u\n", __func__, *result); 1214 return 0; 1215 } 1216 1217 int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix) 1218 { 1219 int rc; 1220 1221 kfree(cifs_sb->prepath); 1222 cifs_sb->prepath = NULL; 1223 1224 if (prefix && *prefix) { 1225 cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC); 1226 if (IS_ERR(cifs_sb->prepath)) { 1227 rc = PTR_ERR(cifs_sb->prepath); 1228 cifs_sb->prepath = NULL; 1229 return rc; 1230 } 1231 if (cifs_sb->prepath) 1232 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); 1233 } 1234 1235 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; 1236 return 0; 1237 } 1238 1239 /* 1240 * Handle weird Windows SMB server behaviour. It responds with 1241 * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for 1242 * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains 1243 * non-ASCII unicode symbols. 1244 */ 1245 int cifs_inval_name_dfs_link_error(const unsigned int xid, 1246 struct cifs_tcon *tcon, 1247 struct cifs_sb_info *cifs_sb, 1248 const char *full_path, 1249 bool *islink) 1250 { 1251 struct cifs_ses *ses = tcon->ses; 1252 size_t len; 1253 char *path; 1254 char *ref_path; 1255 1256 *islink = false; 1257 1258 /* 1259 * Fast path - skip check when @full_path doesn't have a prefix path to 1260 * look up or tcon is not DFS. 1261 */ 1262 if (strlen(full_path) < 2 || !cifs_sb || 1263 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) || 1264 !is_tcon_dfs(tcon)) 1265 return 0; 1266 1267 spin_lock(&tcon->tc_lock); 1268 if (!tcon->origin_fullpath) { 1269 spin_unlock(&tcon->tc_lock); 1270 return 0; 1271 } 1272 spin_unlock(&tcon->tc_lock); 1273 1274 /* 1275 * Slow path - tcon is DFS and @full_path has prefix path, so attempt 1276 * to get a referral to figure out whether it is an DFS link. 1277 */ 1278 len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1; 1279 path = kmalloc(len, GFP_KERNEL); 1280 if (!path) 1281 return -ENOMEM; 1282 1283 scnprintf(path, len, "%s%s", tcon->tree_name, full_path); 1284 ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls, 1285 cifs_remap(cifs_sb)); 1286 kfree(path); 1287 1288 if (IS_ERR(ref_path)) { 1289 if (PTR_ERR(ref_path) != -EINVAL) 1290 return PTR_ERR(ref_path); 1291 } else { 1292 struct dfs_info3_param *refs = NULL; 1293 int num_refs = 0; 1294 1295 /* 1296 * XXX: we are not using dfs_cache_find() here because we might 1297 * end up filling all the DFS cache and thus potentially 1298 * removing cached DFS targets that the client would eventually 1299 * need during failover. 1300 */ 1301 ses = CIFS_DFS_ROOT_SES(ses); 1302 if (ses->server->ops->get_dfs_refer && 1303 !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs, 1304 &num_refs, cifs_sb->local_nls, 1305 cifs_remap(cifs_sb))) 1306 *islink = refs[0].server_type == DFS_TYPE_LINK; 1307 free_dfs_info_array(refs, num_refs); 1308 kfree(ref_path); 1309 } 1310 return 0; 1311 } 1312 #endif 1313 1314 int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry) 1315 { 1316 int timeout = 10; 1317 int rc; 1318 1319 spin_lock(&server->srv_lock); 1320 if (server->tcpStatus != CifsNeedReconnect) { 1321 spin_unlock(&server->srv_lock); 1322 return 0; 1323 } 1324 timeout *= server->nr_targets; 1325 spin_unlock(&server->srv_lock); 1326 1327 /* 1328 * Give demultiplex thread up to 10 seconds to each target available for 1329 * reconnect -- should be greater than cifs socket timeout which is 7 1330 * seconds. 1331 * 1332 * On "soft" mounts we wait once. Hard mounts keep retrying until 1333 * process is killed or server comes back on-line. 1334 */ 1335 do { 1336 rc = wait_event_interruptible_timeout(server->response_q, 1337 (server->tcpStatus != CifsNeedReconnect), 1338 timeout * HZ); 1339 if (rc < 0) { 1340 cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n", 1341 __func__); 1342 return -ERESTARTSYS; 1343 } 1344 1345 /* are we still trying to reconnect? */ 1346 spin_lock(&server->srv_lock); 1347 if (server->tcpStatus != CifsNeedReconnect) { 1348 spin_unlock(&server->srv_lock); 1349 return 0; 1350 } 1351 spin_unlock(&server->srv_lock); 1352 } while (retry); 1353 1354 cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__); 1355 return -EHOSTDOWN; 1356 } 1357