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 /* The xid serves as a useful identifier for each incoming vfs request, 31 in a similar way to the mid which is useful to track each sent smb, 32 and CurrentXid can also provide a running counter (although it 33 will eventually wrap past zero) of the total vfs operations handled 34 since the cifs fs was mounted */ 35 36 unsigned int 37 _get_xid(void) 38 { 39 unsigned int xid; 40 41 spin_lock(&GlobalMid_Lock); 42 GlobalTotalActiveXid++; 43 44 /* keep high water mark for number of simultaneous ops in filesystem */ 45 if (GlobalTotalActiveXid > GlobalMaxActiveXid) 46 GlobalMaxActiveXid = GlobalTotalActiveXid; 47 if (GlobalTotalActiveXid > 65000) 48 cifs_dbg(FYI, "warning: more than 65000 requests active\n"); 49 xid = GlobalCurrentXid++; 50 spin_unlock(&GlobalMid_Lock); 51 return xid; 52 } 53 54 void 55 _free_xid(unsigned int xid) 56 { 57 spin_lock(&GlobalMid_Lock); 58 /* if (GlobalTotalActiveXid == 0) 59 BUG(); */ 60 GlobalTotalActiveXid--; 61 spin_unlock(&GlobalMid_Lock); 62 } 63 64 struct cifs_ses * 65 sesInfoAlloc(void) 66 { 67 struct cifs_ses *ret_buf; 68 69 ret_buf = kzalloc(sizeof(struct cifs_ses), GFP_KERNEL); 70 if (ret_buf) { 71 atomic_inc(&sesInfoAllocCount); 72 spin_lock_init(&ret_buf->ses_lock); 73 ret_buf->ses_status = SES_NEW; 74 ++ret_buf->ses_count; 75 INIT_LIST_HEAD(&ret_buf->smb_ses_list); 76 INIT_LIST_HEAD(&ret_buf->tcon_list); 77 mutex_init(&ret_buf->session_mutex); 78 spin_lock_init(&ret_buf->iface_lock); 79 INIT_LIST_HEAD(&ret_buf->iface_list); 80 spin_lock_init(&ret_buf->chan_lock); 81 } 82 return ret_buf; 83 } 84 85 void 86 sesInfoFree(struct cifs_ses *buf_to_free) 87 { 88 struct cifs_server_iface *iface = NULL, *niface = NULL; 89 90 if (buf_to_free == NULL) { 91 cifs_dbg(FYI, "Null buffer passed to sesInfoFree\n"); 92 return; 93 } 94 95 unload_nls(buf_to_free->local_nls); 96 atomic_dec(&sesInfoAllocCount); 97 kfree(buf_to_free->serverOS); 98 kfree(buf_to_free->serverDomain); 99 kfree(buf_to_free->serverNOS); 100 kfree_sensitive(buf_to_free->password); 101 kfree_sensitive(buf_to_free->password2); 102 kfree(buf_to_free->user_name); 103 kfree(buf_to_free->domainName); 104 kfree(buf_to_free->dns_dom); 105 kfree_sensitive(buf_to_free->auth_key.response); 106 spin_lock(&buf_to_free->iface_lock); 107 list_for_each_entry_safe(iface, niface, &buf_to_free->iface_list, 108 iface_head) 109 kref_put(&iface->refcount, release_iface); 110 spin_unlock(&buf_to_free->iface_lock); 111 kfree_sensitive(buf_to_free); 112 } 113 114 struct cifs_tcon * 115 tcon_info_alloc(bool dir_leases_enabled, enum smb3_tcon_ref_trace trace) 116 { 117 struct cifs_tcon *ret_buf; 118 static atomic_t tcon_debug_id; 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->debug_id = atomic_inc_return(&tcon_debug_id); 136 ret_buf->tc_count = 1; 137 spin_lock_init(&ret_buf->tc_lock); 138 INIT_LIST_HEAD(&ret_buf->openFileList); 139 INIT_LIST_HEAD(&ret_buf->tcon_list); 140 spin_lock_init(&ret_buf->open_file_lock); 141 spin_lock_init(&ret_buf->stat_lock); 142 atomic_set(&ret_buf->num_local_opens, 0); 143 atomic_set(&ret_buf->num_remote_opens, 0); 144 ret_buf->stats_from_time = ktime_get_real_seconds(); 145 #ifdef CONFIG_CIFS_FSCACHE 146 mutex_init(&ret_buf->fscache_lock); 147 #endif 148 trace_smb3_tcon_ref(ret_buf->debug_id, ret_buf->tc_count, trace); 149 #ifdef CONFIG_CIFS_DFS_UPCALL 150 INIT_LIST_HEAD(&ret_buf->dfs_ses_list); 151 #endif 152 153 return ret_buf; 154 } 155 156 void 157 tconInfoFree(struct cifs_tcon *tcon, enum smb3_tcon_ref_trace trace) 158 { 159 if (tcon == NULL) { 160 cifs_dbg(FYI, "Null buffer passed to tconInfoFree\n"); 161 return; 162 } 163 trace_smb3_tcon_ref(tcon->debug_id, tcon->tc_count, trace); 164 free_cached_dirs(tcon->cfids); 165 atomic_dec(&tconInfoAllocCount); 166 kfree(tcon->nativeFileSystem); 167 kfree_sensitive(tcon->password); 168 kfree(tcon->origin_fullpath); 169 kfree(tcon); 170 } 171 172 struct smb_hdr * 173 cifs_buf_get(void) 174 { 175 struct smb_hdr *ret_buf = NULL; 176 /* 177 * SMB2 header is bigger than CIFS one - no problems to clean some 178 * more bytes for CIFS. 179 */ 180 size_t buf_size = sizeof(struct smb2_hdr); 181 182 /* 183 * We could use negotiated size instead of max_msgsize - 184 * but it may be more efficient to always alloc same size 185 * albeit slightly larger than necessary and maxbuffersize 186 * defaults to this and can not be bigger. 187 */ 188 ret_buf = mempool_alloc(cifs_req_poolp, GFP_NOFS); 189 190 /* clear the first few header bytes */ 191 /* for most paths, more is cleared in header_assemble */ 192 memset(ret_buf, 0, buf_size + 3); 193 atomic_inc(&buf_alloc_count); 194 #ifdef CONFIG_CIFS_STATS2 195 atomic_inc(&total_buf_alloc_count); 196 #endif /* CONFIG_CIFS_STATS2 */ 197 198 return ret_buf; 199 } 200 201 void 202 cifs_buf_release(void *buf_to_free) 203 { 204 if (buf_to_free == NULL) { 205 /* cifs_dbg(FYI, "Null buffer passed to cifs_buf_release\n");*/ 206 return; 207 } 208 mempool_free(buf_to_free, cifs_req_poolp); 209 210 atomic_dec(&buf_alloc_count); 211 return; 212 } 213 214 struct smb_hdr * 215 cifs_small_buf_get(void) 216 { 217 struct smb_hdr *ret_buf = NULL; 218 219 /* We could use negotiated size instead of max_msgsize - 220 but it may be more efficient to always alloc same size 221 albeit slightly larger than necessary and maxbuffersize 222 defaults to this and can not be bigger */ 223 ret_buf = mempool_alloc(cifs_sm_req_poolp, GFP_NOFS); 224 /* No need to clear memory here, cleared in header assemble */ 225 /* memset(ret_buf, 0, sizeof(struct smb_hdr) + 27);*/ 226 atomic_inc(&small_buf_alloc_count); 227 #ifdef CONFIG_CIFS_STATS2 228 atomic_inc(&total_small_buf_alloc_count); 229 #endif /* CONFIG_CIFS_STATS2 */ 230 231 return ret_buf; 232 } 233 234 void 235 cifs_small_buf_release(void *buf_to_free) 236 { 237 238 if (buf_to_free == NULL) { 239 cifs_dbg(FYI, "Null buffer passed to cifs_small_buf_release\n"); 240 return; 241 } 242 mempool_free(buf_to_free, cifs_sm_req_poolp); 243 244 atomic_dec(&small_buf_alloc_count); 245 return; 246 } 247 248 void 249 free_rsp_buf(int resp_buftype, void *rsp) 250 { 251 if (resp_buftype == CIFS_SMALL_BUFFER) 252 cifs_small_buf_release(rsp); 253 else if (resp_buftype == CIFS_LARGE_BUFFER) 254 cifs_buf_release(rsp); 255 } 256 257 /* NB: MID can not be set if treeCon not passed in, in that 258 case it is responsibility of caller to set the mid */ 259 void 260 header_assemble(struct smb_hdr *buffer, char smb_command /* command */ , 261 const struct cifs_tcon *treeCon, int word_count 262 /* length of fixed section (word count) in two byte units */) 263 { 264 char *temp = (char *) buffer; 265 266 memset(temp, 0, 256); /* bigger than MAX_CIFS_HDR_SIZE */ 267 268 buffer->smb_buf_length = cpu_to_be32( 269 (2 * word_count) + sizeof(struct smb_hdr) - 270 4 /* RFC 1001 length field does not count */ + 271 2 /* for bcc field itself */) ; 272 273 buffer->Protocol[0] = 0xFF; 274 buffer->Protocol[1] = 'S'; 275 buffer->Protocol[2] = 'M'; 276 buffer->Protocol[3] = 'B'; 277 buffer->Command = smb_command; 278 buffer->Flags = 0x00; /* case sensitive */ 279 buffer->Flags2 = SMBFLG2_KNOWS_LONG_NAMES; 280 buffer->Pid = cpu_to_le16((__u16)current->tgid); 281 buffer->PidHigh = cpu_to_le16((__u16)(current->tgid >> 16)); 282 if (treeCon) { 283 buffer->Tid = treeCon->tid; 284 if (treeCon->ses) { 285 if (treeCon->ses->capabilities & CAP_UNICODE) 286 buffer->Flags2 |= SMBFLG2_UNICODE; 287 if (treeCon->ses->capabilities & CAP_STATUS32) 288 buffer->Flags2 |= SMBFLG2_ERR_STATUS; 289 290 /* Uid is not converted */ 291 buffer->Uid = treeCon->ses->Suid; 292 if (treeCon->ses->server) 293 buffer->Mid = get_next_mid(treeCon->ses->server); 294 } 295 if (treeCon->Flags & SMB_SHARE_IS_IN_DFS) 296 buffer->Flags2 |= SMBFLG2_DFS; 297 if (treeCon->nocase) 298 buffer->Flags |= SMBFLG_CASELESS; 299 if ((treeCon->ses) && (treeCon->ses->server)) 300 if (treeCon->ses->server->sign) 301 buffer->Flags2 |= SMBFLG2_SECURITY_SIGNATURE; 302 } 303 304 /* endian conversion of flags is now done just before sending */ 305 buffer->WordCount = (char) word_count; 306 return; 307 } 308 309 static int 310 check_smb_hdr(struct smb_hdr *smb) 311 { 312 /* does it have the right SMB "signature" ? */ 313 if (*(__le32 *) smb->Protocol != cpu_to_le32(0x424d53ff)) { 314 cifs_dbg(VFS, "Bad protocol string signature header 0x%x\n", 315 *(unsigned int *)smb->Protocol); 316 return 1; 317 } 318 319 /* if it's a response then accept */ 320 if (smb->Flags & SMBFLG_RESPONSE) 321 return 0; 322 323 /* only one valid case where server sends us request */ 324 if (smb->Command == SMB_COM_LOCKING_ANDX) 325 return 0; 326 327 cifs_dbg(VFS, "Server sent request, not response. mid=%u\n", 328 get_mid(smb)); 329 return 1; 330 } 331 332 int 333 checkSMB(char *buf, unsigned int total_read, struct TCP_Server_Info *server) 334 { 335 struct smb_hdr *smb = (struct smb_hdr *)buf; 336 __u32 rfclen = be32_to_cpu(smb->smb_buf_length); 337 __u32 clc_len; /* calculated length */ 338 cifs_dbg(FYI, "checkSMB Length: 0x%x, smb_buf_length: 0x%x\n", 339 total_read, rfclen); 340 341 /* is this frame too small to even get to a BCC? */ 342 if (total_read < 2 + sizeof(struct smb_hdr)) { 343 if ((total_read >= sizeof(struct smb_hdr) - 1) 344 && (smb->Status.CifsError != 0)) { 345 /* it's an error return */ 346 smb->WordCount = 0; 347 /* some error cases do not return wct and bcc */ 348 return 0; 349 } else if ((total_read == sizeof(struct smb_hdr) + 1) && 350 (smb->WordCount == 0)) { 351 char *tmp = (char *)smb; 352 /* Need to work around a bug in two servers here */ 353 /* First, check if the part of bcc they sent was zero */ 354 if (tmp[sizeof(struct smb_hdr)] == 0) { 355 /* some servers return only half of bcc 356 * on simple responses (wct, bcc both zero) 357 * in particular have seen this on 358 * ulogoffX and FindClose. This leaves 359 * one byte of bcc potentially uninitialized 360 */ 361 /* zero rest of bcc */ 362 tmp[sizeof(struct smb_hdr)+1] = 0; 363 return 0; 364 } 365 cifs_dbg(VFS, "rcvd invalid byte count (bcc)\n"); 366 } else { 367 cifs_dbg(VFS, "Length less than smb header size\n"); 368 } 369 return -EIO; 370 } else if (total_read < sizeof(*smb) + 2 * smb->WordCount) { 371 cifs_dbg(VFS, "%s: can't read BCC due to invalid WordCount(%u)\n", 372 __func__, smb->WordCount); 373 return -EIO; 374 } 375 376 /* otherwise, there is enough to get to the BCC */ 377 if (check_smb_hdr(smb)) 378 return -EIO; 379 clc_len = smbCalcSize(smb); 380 381 if (4 + rfclen != total_read) { 382 cifs_dbg(VFS, "Length read does not match RFC1001 length %d\n", 383 rfclen); 384 return -EIO; 385 } 386 387 if (4 + rfclen != clc_len) { 388 __u16 mid = get_mid(smb); 389 /* check if bcc wrapped around for large read responses */ 390 if ((rfclen > 64 * 1024) && (rfclen > clc_len)) { 391 /* check if lengths match mod 64K */ 392 if (((4 + rfclen) & 0xFFFF) == (clc_len & 0xFFFF)) 393 return 0; /* bcc wrapped */ 394 } 395 cifs_dbg(FYI, "Calculated size %u vs length %u mismatch for mid=%u\n", 396 clc_len, 4 + rfclen, mid); 397 398 if (4 + rfclen < clc_len) { 399 cifs_dbg(VFS, "RFC1001 size %u smaller than SMB for mid=%u\n", 400 rfclen, mid); 401 return -EIO; 402 } else if (rfclen > clc_len + 512) { 403 /* 404 * Some servers (Windows XP in particular) send more 405 * data than the lengths in the SMB packet would 406 * indicate on certain calls (byte range locks and 407 * trans2 find first calls in particular). While the 408 * client can handle such a frame by ignoring the 409 * trailing data, we choose limit the amount of extra 410 * data to 512 bytes. 411 */ 412 cifs_dbg(VFS, "RFC1001 size %u more than 512 bytes larger than SMB for mid=%u\n", 413 rfclen, mid); 414 return -EIO; 415 } 416 } 417 return 0; 418 } 419 420 bool 421 is_valid_oplock_break(char *buffer, struct TCP_Server_Info *srv) 422 { 423 struct smb_hdr *buf = (struct smb_hdr *)buffer; 424 struct smb_com_lock_req *pSMB = (struct smb_com_lock_req *)buf; 425 struct TCP_Server_Info *pserver; 426 struct cifs_ses *ses; 427 struct cifs_tcon *tcon; 428 struct cifsInodeInfo *pCifsInode; 429 struct cifsFileInfo *netfile; 430 431 cifs_dbg(FYI, "Checking for oplock break or dnotify response\n"); 432 if ((pSMB->hdr.Command == SMB_COM_NT_TRANSACT) && 433 (pSMB->hdr.Flags & SMBFLG_RESPONSE)) { 434 struct smb_com_transaction_change_notify_rsp *pSMBr = 435 (struct smb_com_transaction_change_notify_rsp *)buf; 436 struct file_notify_information *pnotify; 437 __u32 data_offset = 0; 438 size_t len = srv->total_read - sizeof(pSMBr->hdr.smb_buf_length); 439 440 if (get_bcc(buf) > sizeof(struct file_notify_information)) { 441 data_offset = le32_to_cpu(pSMBr->DataOffset); 442 443 if (data_offset > 444 len - sizeof(struct file_notify_information)) { 445 cifs_dbg(FYI, "Invalid data_offset %u\n", 446 data_offset); 447 return true; 448 } 449 pnotify = (struct file_notify_information *) 450 ((char *)&pSMBr->hdr.Protocol + data_offset); 451 cifs_dbg(FYI, "dnotify on %s Action: 0x%x\n", 452 pnotify->FileName, pnotify->Action); 453 /* cifs_dump_mem("Rcvd notify Data: ",buf, 454 sizeof(struct smb_hdr)+60); */ 455 return true; 456 } 457 if (pSMBr->hdr.Status.CifsError) { 458 cifs_dbg(FYI, "notify err 0x%x\n", 459 pSMBr->hdr.Status.CifsError); 460 return true; 461 } 462 return false; 463 } 464 if (pSMB->hdr.Command != SMB_COM_LOCKING_ANDX) 465 return false; 466 if (pSMB->hdr.Flags & SMBFLG_RESPONSE) { 467 /* no sense logging error on invalid handle on oplock 468 break - harmless race between close request and oplock 469 break response is expected from time to time writing out 470 large dirty files cached on the client */ 471 if ((NT_STATUS_INVALID_HANDLE) == 472 le32_to_cpu(pSMB->hdr.Status.CifsError)) { 473 cifs_dbg(FYI, "Invalid handle on oplock break\n"); 474 return true; 475 } else if (ERRbadfid == 476 le16_to_cpu(pSMB->hdr.Status.DosError.Error)) { 477 return true; 478 } else { 479 return false; /* on valid oplock brk we get "request" */ 480 } 481 } 482 if (pSMB->hdr.WordCount != 8) 483 return false; 484 485 cifs_dbg(FYI, "oplock type 0x%x level 0x%x\n", 486 pSMB->LockType, pSMB->OplockLevel); 487 if (!(pSMB->LockType & LOCKING_ANDX_OPLOCK_RELEASE)) 488 return false; 489 490 /* If server is a channel, select the primary channel */ 491 pserver = SERVER_IS_CHAN(srv) ? srv->primary_server : srv; 492 493 /* look up tcon based on tid & uid */ 494 spin_lock(&cifs_tcp_ses_lock); 495 list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) { 496 if (cifs_ses_exiting(ses)) 497 continue; 498 list_for_each_entry(tcon, &ses->tcon_list, tcon_list) { 499 if (tcon->tid != buf->Tid) 500 continue; 501 502 cifs_stats_inc(&tcon->stats.cifs_stats.num_oplock_brks); 503 spin_lock(&tcon->open_file_lock); 504 list_for_each_entry(netfile, &tcon->openFileList, tlist) { 505 if (pSMB->Fid != netfile->fid.netfid) 506 continue; 507 508 cifs_dbg(FYI, "file id match, oplock break\n"); 509 pCifsInode = CIFS_I(d_inode(netfile->dentry)); 510 511 set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, 512 &pCifsInode->flags); 513 514 netfile->oplock_epoch = 0; 515 netfile->oplock_level = pSMB->OplockLevel; 516 netfile->oplock_break_cancelled = false; 517 cifs_queue_oplock_break(netfile); 518 519 spin_unlock(&tcon->open_file_lock); 520 spin_unlock(&cifs_tcp_ses_lock); 521 return true; 522 } 523 spin_unlock(&tcon->open_file_lock); 524 spin_unlock(&cifs_tcp_ses_lock); 525 cifs_dbg(FYI, "No matching file for oplock break\n"); 526 return true; 527 } 528 } 529 spin_unlock(&cifs_tcp_ses_lock); 530 cifs_dbg(FYI, "Can not process oplock break for non-existent connection\n"); 531 return true; 532 } 533 534 void 535 dump_smb(void *buf, int smb_buf_length) 536 { 537 if (traceSMB == 0) 538 return; 539 540 print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_NONE, 8, 2, buf, 541 smb_buf_length, true); 542 } 543 544 void 545 cifs_autodisable_serverino(struct cifs_sb_info *cifs_sb) 546 { 547 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { 548 struct cifs_tcon *tcon = NULL; 549 550 if (cifs_sb->master_tlink) 551 tcon = cifs_sb_master_tcon(cifs_sb); 552 553 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; 554 cifs_sb->mnt_cifs_serverino_autodisabled = true; 555 cifs_dbg(VFS, "Autodisabling the use of server inode numbers on %s\n", 556 tcon ? tcon->tree_name : "new server"); 557 cifs_dbg(VFS, "The server doesn't seem to support them properly or the files might be on different servers (DFS)\n"); 558 cifs_dbg(VFS, "Hardlinks will not be recognized on this mount. Consider mounting with the \"noserverino\" option to silence this message.\n"); 559 560 } 561 } 562 563 void cifs_set_oplock_level(struct cifsInodeInfo *cinode, __u32 oplock) 564 { 565 oplock &= 0xF; 566 567 if (oplock == OPLOCK_EXCLUSIVE) { 568 cinode->oplock = CIFS_CACHE_WRITE_FLG | CIFS_CACHE_READ_FLG; 569 cifs_dbg(FYI, "Exclusive Oplock granted on inode %p\n", 570 &cinode->netfs.inode); 571 } else if (oplock == OPLOCK_READ) { 572 cinode->oplock = CIFS_CACHE_READ_FLG; 573 cifs_dbg(FYI, "Level II Oplock granted on inode %p\n", 574 &cinode->netfs.inode); 575 } else 576 cinode->oplock = 0; 577 } 578 579 /* 580 * We wait for oplock breaks to be processed before we attempt to perform 581 * writes. 582 */ 583 int cifs_get_writer(struct cifsInodeInfo *cinode) 584 { 585 int rc; 586 587 start: 588 rc = wait_on_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK, 589 TASK_KILLABLE); 590 if (rc) 591 return rc; 592 593 spin_lock(&cinode->writers_lock); 594 if (!cinode->writers) 595 set_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 596 cinode->writers++; 597 /* Check to see if we have started servicing an oplock break */ 598 if (test_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags)) { 599 cinode->writers--; 600 if (cinode->writers == 0) { 601 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 602 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 603 } 604 spin_unlock(&cinode->writers_lock); 605 goto start; 606 } 607 spin_unlock(&cinode->writers_lock); 608 return 0; 609 } 610 611 void cifs_put_writer(struct cifsInodeInfo *cinode) 612 { 613 spin_lock(&cinode->writers_lock); 614 cinode->writers--; 615 if (cinode->writers == 0) { 616 clear_bit(CIFS_INODE_PENDING_WRITERS, &cinode->flags); 617 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_WRITERS); 618 } 619 spin_unlock(&cinode->writers_lock); 620 } 621 622 /** 623 * cifs_queue_oplock_break - queue the oplock break handler for cfile 624 * @cfile: The file to break the oplock on 625 * 626 * This function is called from the demultiplex thread when it 627 * receives an oplock break for @cfile. 628 * 629 * Assumes the tcon->open_file_lock is held. 630 * Assumes cfile->file_info_lock is NOT held. 631 */ 632 void cifs_queue_oplock_break(struct cifsFileInfo *cfile) 633 { 634 /* 635 * Bump the handle refcount now while we hold the 636 * open_file_lock to enforce the validity of it for the oplock 637 * break handler. The matching put is done at the end of the 638 * handler. 639 */ 640 cifsFileInfo_get(cfile); 641 642 queue_work(cifsoplockd_wq, &cfile->oplock_break); 643 } 644 645 void cifs_done_oplock_break(struct cifsInodeInfo *cinode) 646 { 647 clear_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags); 648 wake_up_bit(&cinode->flags, CIFS_INODE_PENDING_OPLOCK_BREAK); 649 } 650 651 bool 652 backup_cred(struct cifs_sb_info *cifs_sb) 653 { 654 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPUID) { 655 if (uid_eq(cifs_sb->ctx->backupuid, current_fsuid())) 656 return true; 657 } 658 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_BACKUPGID) { 659 if (in_group_p(cifs_sb->ctx->backupgid)) 660 return true; 661 } 662 663 return false; 664 } 665 666 void 667 cifs_del_pending_open(struct cifs_pending_open *open) 668 { 669 spin_lock(&tlink_tcon(open->tlink)->open_file_lock); 670 list_del(&open->olist); 671 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 672 } 673 674 void 675 cifs_add_pending_open_locked(struct cifs_fid *fid, struct tcon_link *tlink, 676 struct cifs_pending_open *open) 677 { 678 memcpy(open->lease_key, fid->lease_key, SMB2_LEASE_KEY_SIZE); 679 open->oplock = CIFS_OPLOCK_NO_CHANGE; 680 open->tlink = tlink; 681 fid->pending_open = open; 682 list_add_tail(&open->olist, &tlink_tcon(tlink)->pending_opens); 683 } 684 685 void 686 cifs_add_pending_open(struct cifs_fid *fid, struct tcon_link *tlink, 687 struct cifs_pending_open *open) 688 { 689 spin_lock(&tlink_tcon(tlink)->open_file_lock); 690 cifs_add_pending_open_locked(fid, tlink, open); 691 spin_unlock(&tlink_tcon(open->tlink)->open_file_lock); 692 } 693 694 /* 695 * Critical section which runs after acquiring deferred_lock. 696 * As there is no reference count on cifs_deferred_close, pdclose 697 * should not be used outside deferred_lock. 698 */ 699 bool 700 cifs_is_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close **pdclose) 701 { 702 struct cifs_deferred_close *dclose; 703 704 list_for_each_entry(dclose, &CIFS_I(d_inode(cfile->dentry))->deferred_closes, dlist) { 705 if ((dclose->netfid == cfile->fid.netfid) && 706 (dclose->persistent_fid == cfile->fid.persistent_fid) && 707 (dclose->volatile_fid == cfile->fid.volatile_fid)) { 708 *pdclose = dclose; 709 return true; 710 } 711 } 712 return false; 713 } 714 715 /* 716 * Critical section which runs after acquiring deferred_lock. 717 */ 718 void 719 cifs_add_deferred_close(struct cifsFileInfo *cfile, struct cifs_deferred_close *dclose) 720 { 721 bool is_deferred = false; 722 struct cifs_deferred_close *pdclose; 723 724 is_deferred = cifs_is_deferred_close(cfile, &pdclose); 725 if (is_deferred) { 726 kfree(dclose); 727 return; 728 } 729 730 dclose->tlink = cfile->tlink; 731 dclose->netfid = cfile->fid.netfid; 732 dclose->persistent_fid = cfile->fid.persistent_fid; 733 dclose->volatile_fid = cfile->fid.volatile_fid; 734 list_add_tail(&dclose->dlist, &CIFS_I(d_inode(cfile->dentry))->deferred_closes); 735 } 736 737 /* 738 * Critical section which runs after acquiring deferred_lock. 739 */ 740 void 741 cifs_del_deferred_close(struct cifsFileInfo *cfile) 742 { 743 bool is_deferred = false; 744 struct cifs_deferred_close *dclose; 745 746 is_deferred = cifs_is_deferred_close(cfile, &dclose); 747 if (!is_deferred) 748 return; 749 list_del(&dclose->dlist); 750 kfree(dclose); 751 } 752 753 void 754 cifs_close_deferred_file(struct cifsInodeInfo *cifs_inode) 755 { 756 struct cifsFileInfo *cfile = NULL; 757 struct file_list *tmp_list, *tmp_next_list; 758 LIST_HEAD(file_head); 759 760 if (cifs_inode == NULL) 761 return; 762 763 spin_lock(&cifs_inode->open_file_lock); 764 list_for_each_entry(cfile, &cifs_inode->openFileList, flist) { 765 if (delayed_work_pending(&cfile->deferred)) { 766 if (cancel_delayed_work(&cfile->deferred)) { 767 spin_lock(&cifs_inode->deferred_lock); 768 cifs_del_deferred_close(cfile); 769 spin_unlock(&cifs_inode->deferred_lock); 770 771 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 772 if (tmp_list == NULL) 773 break; 774 tmp_list->cfile = cfile; 775 list_add_tail(&tmp_list->list, &file_head); 776 } 777 } 778 } 779 spin_unlock(&cifs_inode->open_file_lock); 780 781 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 782 _cifsFileInfo_put(tmp_list->cfile, false, false); 783 list_del(&tmp_list->list); 784 kfree(tmp_list); 785 } 786 } 787 788 void 789 cifs_close_all_deferred_files(struct cifs_tcon *tcon) 790 { 791 struct cifsFileInfo *cfile; 792 struct file_list *tmp_list, *tmp_next_list; 793 LIST_HEAD(file_head); 794 795 spin_lock(&tcon->open_file_lock); 796 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 797 if (delayed_work_pending(&cfile->deferred)) { 798 if (cancel_delayed_work(&cfile->deferred)) { 799 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 800 cifs_del_deferred_close(cfile); 801 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 802 803 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 804 if (tmp_list == NULL) 805 break; 806 tmp_list->cfile = cfile; 807 list_add_tail(&tmp_list->list, &file_head); 808 } 809 } 810 } 811 spin_unlock(&tcon->open_file_lock); 812 813 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 814 _cifsFileInfo_put(tmp_list->cfile, true, false); 815 list_del(&tmp_list->list); 816 kfree(tmp_list); 817 } 818 } 819 void 820 cifs_close_deferred_file_under_dentry(struct cifs_tcon *tcon, const char *path) 821 { 822 struct cifsFileInfo *cfile; 823 struct file_list *tmp_list, *tmp_next_list; 824 void *page; 825 const char *full_path; 826 LIST_HEAD(file_head); 827 828 page = alloc_dentry_path(); 829 spin_lock(&tcon->open_file_lock); 830 list_for_each_entry(cfile, &tcon->openFileList, tlist) { 831 full_path = build_path_from_dentry(cfile->dentry, page); 832 if (strstr(full_path, path)) { 833 if (delayed_work_pending(&cfile->deferred)) { 834 if (cancel_delayed_work(&cfile->deferred)) { 835 spin_lock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 836 cifs_del_deferred_close(cfile); 837 spin_unlock(&CIFS_I(d_inode(cfile->dentry))->deferred_lock); 838 839 tmp_list = kmalloc(sizeof(struct file_list), GFP_ATOMIC); 840 if (tmp_list == NULL) 841 break; 842 tmp_list->cfile = cfile; 843 list_add_tail(&tmp_list->list, &file_head); 844 } 845 } 846 } 847 } 848 spin_unlock(&tcon->open_file_lock); 849 850 list_for_each_entry_safe(tmp_list, tmp_next_list, &file_head, list) { 851 _cifsFileInfo_put(tmp_list->cfile, true, false); 852 list_del(&tmp_list->list); 853 kfree(tmp_list); 854 } 855 free_dentry_path(page); 856 } 857 858 /* 859 * If a dentry has been deleted, all corresponding open handles should know that 860 * so that we do not defer close them. 861 */ 862 void cifs_mark_open_handles_for_deleted_file(struct inode *inode, 863 const char *path) 864 { 865 struct cifsFileInfo *cfile; 866 void *page; 867 const char *full_path; 868 struct cifsInodeInfo *cinode = CIFS_I(inode); 869 870 page = alloc_dentry_path(); 871 spin_lock(&cinode->open_file_lock); 872 873 /* 874 * note: we need to construct path from dentry and compare only if the 875 * inode has any hardlinks. When number of hardlinks is 1, we can just 876 * mark all open handles since they are going to be from the same file. 877 */ 878 if (inode->i_nlink > 1) { 879 list_for_each_entry(cfile, &cinode->openFileList, flist) { 880 full_path = build_path_from_dentry(cfile->dentry, page); 881 if (!IS_ERR(full_path) && strcmp(full_path, path) == 0) 882 cfile->status_file_deleted = true; 883 } 884 } else { 885 list_for_each_entry(cfile, &cinode->openFileList, flist) 886 cfile->status_file_deleted = true; 887 } 888 spin_unlock(&cinode->open_file_lock); 889 free_dentry_path(page); 890 } 891 892 /* parses DFS referral V3 structure 893 * caller is responsible for freeing target_nodes 894 * returns: 895 * - on success - 0 896 * - on failure - errno 897 */ 898 int 899 parse_dfs_referrals(struct get_dfs_referral_rsp *rsp, u32 rsp_size, 900 unsigned int *num_of_nodes, 901 struct dfs_info3_param **target_nodes, 902 const struct nls_table *nls_codepage, int remap, 903 const char *searchName, bool is_unicode) 904 { 905 int i, rc = 0; 906 char *data_end; 907 struct dfs_referral_level_3 *ref; 908 909 *num_of_nodes = le16_to_cpu(rsp->NumberOfReferrals); 910 911 if (*num_of_nodes < 1) { 912 cifs_dbg(VFS | ONCE, "%s: [path=%s] num_referrals must be at least > 0, but we got %d\n", 913 __func__, searchName, *num_of_nodes); 914 rc = -ENOENT; 915 goto parse_DFS_referrals_exit; 916 } 917 918 ref = (struct dfs_referral_level_3 *) &(rsp->referrals); 919 if (ref->VersionNumber != cpu_to_le16(3)) { 920 cifs_dbg(VFS, "Referrals of V%d version are not supported, should be V3\n", 921 le16_to_cpu(ref->VersionNumber)); 922 rc = -EINVAL; 923 goto parse_DFS_referrals_exit; 924 } 925 926 /* get the upper boundary of the resp buffer */ 927 data_end = (char *)rsp + rsp_size; 928 929 cifs_dbg(FYI, "num_referrals: %d dfs flags: 0x%x ...\n", 930 *num_of_nodes, le32_to_cpu(rsp->DFSFlags)); 931 932 *target_nodes = kcalloc(*num_of_nodes, sizeof(struct dfs_info3_param), 933 GFP_KERNEL); 934 if (*target_nodes == NULL) { 935 rc = -ENOMEM; 936 goto parse_DFS_referrals_exit; 937 } 938 939 /* collect necessary data from referrals */ 940 for (i = 0; i < *num_of_nodes; i++) { 941 char *temp; 942 int max_len; 943 struct dfs_info3_param *node = (*target_nodes)+i; 944 945 node->flags = le32_to_cpu(rsp->DFSFlags); 946 if (is_unicode) { 947 __le16 *tmp = kmalloc(strlen(searchName)*2 + 2, 948 GFP_KERNEL); 949 if (tmp == NULL) { 950 rc = -ENOMEM; 951 goto parse_DFS_referrals_exit; 952 } 953 cifsConvertToUTF16((__le16 *) tmp, searchName, 954 PATH_MAX, nls_codepage, remap); 955 node->path_consumed = cifs_utf16_bytes(tmp, 956 le16_to_cpu(rsp->PathConsumed), 957 nls_codepage); 958 kfree(tmp); 959 } else 960 node->path_consumed = le16_to_cpu(rsp->PathConsumed); 961 962 node->server_type = le16_to_cpu(ref->ServerType); 963 node->ref_flag = le16_to_cpu(ref->ReferralEntryFlags); 964 965 /* copy DfsPath */ 966 temp = (char *)ref + le16_to_cpu(ref->DfsPathOffset); 967 max_len = data_end - temp; 968 node->path_name = cifs_strndup_from_utf16(temp, max_len, 969 is_unicode, nls_codepage); 970 if (!node->path_name) { 971 rc = -ENOMEM; 972 goto parse_DFS_referrals_exit; 973 } 974 975 /* copy link target UNC */ 976 temp = (char *)ref + le16_to_cpu(ref->NetworkAddressOffset); 977 max_len = data_end - temp; 978 node->node_name = cifs_strndup_from_utf16(temp, max_len, 979 is_unicode, nls_codepage); 980 if (!node->node_name) { 981 rc = -ENOMEM; 982 goto parse_DFS_referrals_exit; 983 } 984 985 node->ttl = le32_to_cpu(ref->TimeToLive); 986 987 ref++; 988 } 989 990 parse_DFS_referrals_exit: 991 if (rc) { 992 free_dfs_info_array(*target_nodes, *num_of_nodes); 993 *target_nodes = NULL; 994 *num_of_nodes = 0; 995 } 996 return rc; 997 } 998 999 /** 1000 * cifs_alloc_hash - allocate hash and hash context together 1001 * @name: The name of the crypto hash algo 1002 * @sdesc: SHASH descriptor where to put the pointer to the hash TFM 1003 * 1004 * The caller has to make sure @sdesc is initialized to either NULL or 1005 * a valid context. It can be freed via cifs_free_hash(). 1006 */ 1007 int 1008 cifs_alloc_hash(const char *name, struct shash_desc **sdesc) 1009 { 1010 int rc = 0; 1011 struct crypto_shash *alg = NULL; 1012 1013 if (*sdesc) 1014 return 0; 1015 1016 alg = crypto_alloc_shash(name, 0, 0); 1017 if (IS_ERR(alg)) { 1018 cifs_dbg(VFS, "Could not allocate shash TFM '%s'\n", name); 1019 rc = PTR_ERR(alg); 1020 *sdesc = NULL; 1021 return rc; 1022 } 1023 1024 *sdesc = kmalloc(sizeof(struct shash_desc) + crypto_shash_descsize(alg), GFP_KERNEL); 1025 if (*sdesc == NULL) { 1026 cifs_dbg(VFS, "no memory left to allocate shash TFM '%s'\n", name); 1027 crypto_free_shash(alg); 1028 return -ENOMEM; 1029 } 1030 1031 (*sdesc)->tfm = alg; 1032 return 0; 1033 } 1034 1035 /** 1036 * cifs_free_hash - free hash and hash context together 1037 * @sdesc: Where to find the pointer to the hash TFM 1038 * 1039 * Freeing a NULL descriptor is safe. 1040 */ 1041 void 1042 cifs_free_hash(struct shash_desc **sdesc) 1043 { 1044 if (unlikely(!sdesc) || !*sdesc) 1045 return; 1046 1047 if ((*sdesc)->tfm) { 1048 crypto_free_shash((*sdesc)->tfm); 1049 (*sdesc)->tfm = NULL; 1050 } 1051 1052 kfree_sensitive(*sdesc); 1053 *sdesc = NULL; 1054 } 1055 1056 void extract_unc_hostname(const char *unc, const char **h, size_t *len) 1057 { 1058 const char *end; 1059 1060 /* skip initial slashes */ 1061 while (*unc && (*unc == '\\' || *unc == '/')) 1062 unc++; 1063 1064 end = unc; 1065 1066 while (*end && !(*end == '\\' || *end == '/')) 1067 end++; 1068 1069 *h = unc; 1070 *len = end - unc; 1071 } 1072 1073 /** 1074 * copy_path_name - copy src path to dst, possibly truncating 1075 * @dst: The destination buffer 1076 * @src: The source name 1077 * 1078 * returns number of bytes written (including trailing nul) 1079 */ 1080 int copy_path_name(char *dst, const char *src) 1081 { 1082 int name_len; 1083 1084 /* 1085 * PATH_MAX includes nul, so if strlen(src) >= PATH_MAX it 1086 * will truncate and strlen(dst) will be PATH_MAX-1 1087 */ 1088 name_len = strscpy(dst, src, PATH_MAX); 1089 if (WARN_ON_ONCE(name_len < 0)) 1090 name_len = PATH_MAX-1; 1091 1092 /* we count the trailing nul */ 1093 name_len++; 1094 return name_len; 1095 } 1096 1097 struct super_cb_data { 1098 void *data; 1099 struct super_block *sb; 1100 }; 1101 1102 static void tcon_super_cb(struct super_block *sb, void *arg) 1103 { 1104 struct super_cb_data *sd = arg; 1105 struct cifs_sb_info *cifs_sb; 1106 struct cifs_tcon *t1 = sd->data, *t2; 1107 1108 if (sd->sb) 1109 return; 1110 1111 cifs_sb = CIFS_SB(sb); 1112 t2 = cifs_sb_master_tcon(cifs_sb); 1113 1114 spin_lock(&t2->tc_lock); 1115 if ((t1->ses == t2->ses || 1116 t1->ses->dfs_root_ses == t2->ses->dfs_root_ses) && 1117 t1->ses->server == t2->ses->server && 1118 t2->origin_fullpath && 1119 dfs_src_pathname_equal(t2->origin_fullpath, t1->origin_fullpath)) 1120 sd->sb = sb; 1121 spin_unlock(&t2->tc_lock); 1122 } 1123 1124 static struct super_block *__cifs_get_super(void (*f)(struct super_block *, void *), 1125 void *data) 1126 { 1127 struct super_cb_data sd = { 1128 .data = data, 1129 .sb = NULL, 1130 }; 1131 struct file_system_type **fs_type = (struct file_system_type *[]) { 1132 &cifs_fs_type, &smb3_fs_type, NULL, 1133 }; 1134 1135 for (; *fs_type; fs_type++) { 1136 iterate_supers_type(*fs_type, f, &sd); 1137 if (sd.sb) { 1138 /* 1139 * Grab an active reference in order to prevent automounts (DFS links) 1140 * of expiring and then freeing up our cifs superblock pointer while 1141 * we're doing failover. 1142 */ 1143 cifs_sb_active(sd.sb); 1144 return sd.sb; 1145 } 1146 } 1147 pr_warn_once("%s: could not find dfs superblock\n", __func__); 1148 return ERR_PTR(-EINVAL); 1149 } 1150 1151 static void __cifs_put_super(struct super_block *sb) 1152 { 1153 if (!IS_ERR_OR_NULL(sb)) 1154 cifs_sb_deactive(sb); 1155 } 1156 1157 struct super_block *cifs_get_dfs_tcon_super(struct cifs_tcon *tcon) 1158 { 1159 spin_lock(&tcon->tc_lock); 1160 if (!tcon->origin_fullpath) { 1161 spin_unlock(&tcon->tc_lock); 1162 return ERR_PTR(-ENOENT); 1163 } 1164 spin_unlock(&tcon->tc_lock); 1165 return __cifs_get_super(tcon_super_cb, tcon); 1166 } 1167 1168 void cifs_put_tcp_super(struct super_block *sb) 1169 { 1170 __cifs_put_super(sb); 1171 } 1172 1173 #ifdef CONFIG_CIFS_DFS_UPCALL 1174 int match_target_ip(struct TCP_Server_Info *server, 1175 const char *host, size_t hostlen, 1176 bool *result) 1177 { 1178 struct sockaddr_storage ss; 1179 int rc; 1180 1181 cifs_dbg(FYI, "%s: hostname=%.*s\n", __func__, (int)hostlen, host); 1182 1183 *result = false; 1184 1185 rc = dns_resolve_name(server->dns_dom, host, hostlen, 1186 (struct sockaddr *)&ss); 1187 if (rc < 0) 1188 return rc; 1189 1190 spin_lock(&server->srv_lock); 1191 *result = cifs_match_ipaddr((struct sockaddr *)&server->dstaddr, (struct sockaddr *)&ss); 1192 spin_unlock(&server->srv_lock); 1193 cifs_dbg(FYI, "%s: ip addresses matched: %s\n", __func__, str_yes_no(*result)); 1194 return 0; 1195 } 1196 1197 int cifs_update_super_prepath(struct cifs_sb_info *cifs_sb, char *prefix) 1198 { 1199 int rc; 1200 1201 kfree(cifs_sb->prepath); 1202 cifs_sb->prepath = NULL; 1203 1204 if (prefix && *prefix) { 1205 cifs_sb->prepath = cifs_sanitize_prepath(prefix, GFP_ATOMIC); 1206 if (IS_ERR(cifs_sb->prepath)) { 1207 rc = PTR_ERR(cifs_sb->prepath); 1208 cifs_sb->prepath = NULL; 1209 return rc; 1210 } 1211 if (cifs_sb->prepath) 1212 convert_delimiter(cifs_sb->prepath, CIFS_DIR_SEP(cifs_sb)); 1213 } 1214 1215 cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_USE_PREFIX_PATH; 1216 return 0; 1217 } 1218 1219 /* 1220 * Handle weird Windows SMB server behaviour. It responds with 1221 * STATUS_OBJECT_NAME_INVALID code to SMB2 QUERY_INFO request for 1222 * "\<server>\<dfsname>\<linkpath>" DFS reference, where <dfsname> contains 1223 * non-ASCII unicode symbols. 1224 */ 1225 int cifs_inval_name_dfs_link_error(const unsigned int xid, 1226 struct cifs_tcon *tcon, 1227 struct cifs_sb_info *cifs_sb, 1228 const char *full_path, 1229 bool *islink) 1230 { 1231 struct TCP_Server_Info *server = tcon->ses->server; 1232 struct cifs_ses *ses = tcon->ses; 1233 size_t len; 1234 char *path; 1235 char *ref_path; 1236 1237 *islink = false; 1238 1239 /* 1240 * Fast path - skip check when @full_path doesn't have a prefix path to 1241 * look up or tcon is not DFS. 1242 */ 1243 if (strlen(full_path) < 2 || !cifs_sb || 1244 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS) || 1245 !is_tcon_dfs(tcon)) 1246 return 0; 1247 1248 spin_lock(&server->srv_lock); 1249 if (!server->leaf_fullpath) { 1250 spin_unlock(&server->srv_lock); 1251 return 0; 1252 } 1253 spin_unlock(&server->srv_lock); 1254 1255 /* 1256 * Slow path - tcon is DFS and @full_path has prefix path, so attempt 1257 * to get a referral to figure out whether it is an DFS link. 1258 */ 1259 len = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1) + strlen(full_path) + 1; 1260 path = kmalloc(len, GFP_KERNEL); 1261 if (!path) 1262 return -ENOMEM; 1263 1264 scnprintf(path, len, "%s%s", tcon->tree_name, full_path); 1265 ref_path = dfs_cache_canonical_path(path + 1, cifs_sb->local_nls, 1266 cifs_remap(cifs_sb)); 1267 kfree(path); 1268 1269 if (IS_ERR(ref_path)) { 1270 if (PTR_ERR(ref_path) != -EINVAL) 1271 return PTR_ERR(ref_path); 1272 } else { 1273 struct dfs_info3_param *refs = NULL; 1274 int num_refs = 0; 1275 1276 /* 1277 * XXX: we are not using dfs_cache_find() here because we might 1278 * end up filling all the DFS cache and thus potentially 1279 * removing cached DFS targets that the client would eventually 1280 * need during failover. 1281 */ 1282 ses = CIFS_DFS_ROOT_SES(ses); 1283 if (ses->server->ops->get_dfs_refer && 1284 !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs, 1285 &num_refs, cifs_sb->local_nls, 1286 cifs_remap(cifs_sb))) 1287 *islink = refs[0].server_type == DFS_TYPE_LINK; 1288 free_dfs_info_array(refs, num_refs); 1289 kfree(ref_path); 1290 } 1291 return 0; 1292 } 1293 #endif 1294 1295 int cifs_wait_for_server_reconnect(struct TCP_Server_Info *server, bool retry) 1296 { 1297 int timeout = 10; 1298 int rc; 1299 1300 spin_lock(&server->srv_lock); 1301 if (server->tcpStatus != CifsNeedReconnect) { 1302 spin_unlock(&server->srv_lock); 1303 return 0; 1304 } 1305 timeout *= server->nr_targets; 1306 spin_unlock(&server->srv_lock); 1307 1308 /* 1309 * Give demultiplex thread up to 10 seconds to each target available for 1310 * reconnect -- should be greater than cifs socket timeout which is 7 1311 * seconds. 1312 * 1313 * On "soft" mounts we wait once. Hard mounts keep retrying until 1314 * process is killed or server comes back on-line. 1315 */ 1316 do { 1317 rc = wait_event_interruptible_timeout(server->response_q, 1318 (server->tcpStatus != CifsNeedReconnect), 1319 timeout * HZ); 1320 if (rc < 0) { 1321 cifs_dbg(FYI, "%s: aborting reconnect due to received signal\n", 1322 __func__); 1323 return -ERESTARTSYS; 1324 } 1325 1326 /* are we still trying to reconnect? */ 1327 spin_lock(&server->srv_lock); 1328 if (server->tcpStatus != CifsNeedReconnect) { 1329 spin_unlock(&server->srv_lock); 1330 return 0; 1331 } 1332 spin_unlock(&server->srv_lock); 1333 } while (retry); 1334 1335 cifs_dbg(FYI, "%s: gave up waiting on reconnect\n", __func__); 1336 return -EHOSTDOWN; 1337 } 1338