1 // SPDX-License-Identifier: LGPL-2.1 2 /* 3 * 4 * Directory search handling 5 * 6 * Copyright (C) International Business Machines Corp., 2004, 2008 7 * Copyright (C) Red Hat, Inc., 2011 8 * Author(s): Steve French (sfrench@us.ibm.com) 9 * 10 */ 11 #include <linux/fs.h> 12 #include <linux/pagemap.h> 13 #include <linux/slab.h> 14 #include <linux/stat.h> 15 #include "cifspdu.h" 16 #include "cifsglob.h" 17 #include "cifsproto.h" 18 #include "cifs_unicode.h" 19 #include "cifs_debug.h" 20 #include "cifs_fs_sb.h" 21 #include "cifsfs.h" 22 #include "smb2proto.h" 23 #include "fs_context.h" 24 #include "cached_dir.h" 25 26 /* 27 * To be safe - for UCS to UTF-8 with strings loaded with the rare long 28 * characters alloc more to account for such multibyte target UTF-8 29 * characters. 30 */ 31 #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2) 32 33 #ifdef CONFIG_CIFS_DEBUG2 34 static void dump_cifs_file_struct(struct file *file, char *label) 35 { 36 struct cifsFileInfo *cf; 37 38 if (file) { 39 cf = file->private_data; 40 if (cf == NULL) { 41 cifs_dbg(FYI, "empty cifs private file data\n"); 42 return; 43 } 44 if (cf->invalidHandle) 45 cifs_dbg(FYI, "Invalid handle\n"); 46 if (cf->srch_inf.endOfSearch) 47 cifs_dbg(FYI, "end of search\n"); 48 if (cf->srch_inf.emptyDir) 49 cifs_dbg(FYI, "empty dir\n"); 50 } 51 } 52 #else 53 static inline void dump_cifs_file_struct(struct file *file, char *label) 54 { 55 } 56 #endif /* DEBUG2 */ 57 58 /* 59 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT 60 * 61 * Find the dentry that matches "name". If there isn't one, create one. If it's 62 * a negative dentry or the uniqueid or filetype(mode) changed, 63 * then drop it and recreate it. 64 */ 65 static void 66 cifs_prime_dcache(struct dentry *parent, struct qstr *name, 67 struct cifs_fattr *fattr) 68 { 69 struct dentry *dentry, *alias; 70 struct inode *inode; 71 struct super_block *sb = parent->d_sb; 72 struct cifs_sb_info *cifs_sb = CIFS_SB(sb); 73 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); 74 75 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name); 76 77 dentry = d_hash_and_lookup(parent, name); 78 if (!dentry) { 79 /* 80 * If we know that the inode will need to be revalidated 81 * immediately, then don't create a new dentry for it. 82 * We'll end up doing an on the wire call either way and 83 * this spares us an invalidation. 84 */ 85 if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL) 86 return; 87 retry: 88 dentry = d_alloc_parallel(parent, name, &wq); 89 } 90 if (IS_ERR(dentry)) 91 return; 92 if (!d_in_lookup(dentry)) { 93 inode = d_inode(dentry); 94 if (inode) { 95 if (d_mountpoint(dentry)) { 96 dput(dentry); 97 return; 98 } 99 /* 100 * If we're generating inode numbers, then we don't 101 * want to clobber the existing one with the one that 102 * the readdir code created. 103 */ 104 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) 105 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid; 106 107 /* update inode in place 108 * if both i_ino and i_mode didn't change */ 109 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid && 110 cifs_fattr_to_inode(inode, fattr) == 0) { 111 dput(dentry); 112 return; 113 } 114 } 115 d_invalidate(dentry); 116 dput(dentry); 117 goto retry; 118 } else { 119 inode = cifs_iget(sb, fattr); 120 if (!inode) 121 inode = ERR_PTR(-ENOMEM); 122 alias = d_splice_alias(inode, dentry); 123 d_lookup_done(dentry); 124 if (alias && !IS_ERR(alias)) 125 dput(alias); 126 } 127 dput(dentry); 128 } 129 130 static bool reparse_file_needs_reval(const struct cifs_fattr *fattr) 131 { 132 if (!(fattr->cf_cifsattrs & ATTR_REPARSE)) 133 return false; 134 /* 135 * The DFS tags should be only intepreted by server side as per 136 * MS-FSCC 2.1.2.1, but let's include them anyway. 137 * 138 * Besides, if cf_cifstag is unset (0), then we still need it to be 139 * revalidated to know exactly what reparse point it is. 140 */ 141 switch (fattr->cf_cifstag) { 142 case IO_REPARSE_TAG_DFS: 143 case IO_REPARSE_TAG_DFSR: 144 case IO_REPARSE_TAG_SYMLINK: 145 case IO_REPARSE_TAG_NFS: 146 case IO_REPARSE_TAG_MOUNT_POINT: 147 case 0: 148 return true; 149 } 150 return false; 151 } 152 153 static void 154 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) 155 { 156 struct cifs_open_info_data data = { 157 .reparse = { .tag = fattr->cf_cifstag, }, 158 }; 159 160 fattr->cf_uid = cifs_sb->ctx->linux_uid; 161 fattr->cf_gid = cifs_sb->ctx->linux_gid; 162 163 /* 164 * The IO_REPARSE_TAG_LX_ tags originally were used by WSL but they 165 * are preferred by the Linux client in some cases since, unlike 166 * the NFS reparse tag (or EAs), they don't require an extra query 167 * to determine which type of special file they represent. 168 * TODO: go through all documented reparse tags to see if we can 169 * reasonably map some of them to directories vs. files vs. symlinks 170 */ 171 if ((fattr->cf_cifsattrs & ATTR_REPARSE) && 172 cifs_reparse_point_to_fattr(cifs_sb, fattr, &data)) 173 goto out_reparse; 174 175 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { 176 fattr->cf_mode = S_IFDIR | cifs_sb->ctx->dir_mode; 177 fattr->cf_dtype = DT_DIR; 178 } else { 179 fattr->cf_mode = S_IFREG | cifs_sb->ctx->file_mode; 180 fattr->cf_dtype = DT_REG; 181 } 182 183 out_reparse: 184 /* 185 * We need to revalidate it further to make a decision about whether it 186 * is a symbolic link, DFS referral or a reparse point with a direct 187 * access like junctions, deduplicated files, NFS symlinks. 188 */ 189 if (reparse_file_needs_reval(fattr)) 190 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 191 192 /* non-unix readdir doesn't provide nlink */ 193 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; 194 195 if (fattr->cf_cifsattrs & ATTR_READONLY) 196 fattr->cf_mode &= ~S_IWUGO; 197 198 /* 199 * We of course don't get ACL info in FIND_FIRST/NEXT results, so 200 * mark it for revalidation so that "ls -l" will look right. It might 201 * be super-slow, but if we don't do this then the ownership of files 202 * may look wrong since the inodes may not have timed out by the time 203 * "ls" does a stat() call on them. 204 */ 205 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) || 206 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID)) 207 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 208 209 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL && 210 fattr->cf_cifsattrs & ATTR_SYSTEM) { 211 if (fattr->cf_eof == 0) { 212 fattr->cf_mode &= ~S_IFMT; 213 fattr->cf_mode |= S_IFIFO; 214 fattr->cf_dtype = DT_FIFO; 215 } else { 216 /* 217 * trying to get the type and mode via SFU can be slow, 218 * so just call those regular files for now, and mark 219 * for reval 220 */ 221 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 222 } 223 } 224 } 225 226 /* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */ 227 static void 228 cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info, 229 struct cifs_sb_info *cifs_sb) 230 { 231 struct smb2_posix_info_parsed parsed; 232 233 posix_info_parse(info, NULL, &parsed); 234 235 memset(fattr, 0, sizeof(*fattr)); 236 fattr->cf_uniqueid = le64_to_cpu(info->Inode); 237 fattr->cf_bytes = le64_to_cpu(info->AllocationSize); 238 fattr->cf_eof = le64_to_cpu(info->EndOfFile); 239 240 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime); 241 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime); 242 fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime); 243 244 fattr->cf_nlink = le32_to_cpu(info->HardLinks); 245 fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes); 246 247 /* 248 * Since we set the inode type below we need to mask off 249 * to avoid strange results if bits set above. 250 * XXX: why not make server&client use the type bits? 251 */ 252 fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT; 253 254 cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n", 255 le32_to_cpu(info->DeviceId), 256 le32_to_cpu(info->ReparseTag), 257 le32_to_cpu(info->Mode)); 258 259 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { 260 fattr->cf_mode |= S_IFDIR; 261 fattr->cf_dtype = DT_DIR; 262 } else { 263 /* 264 * mark anything that is not a dir as regular 265 * file. special files should have the REPARSE 266 * attribute and will be marked as needing revaluation 267 */ 268 fattr->cf_mode |= S_IFREG; 269 fattr->cf_dtype = DT_REG; 270 } 271 272 if (reparse_file_needs_reval(fattr)) 273 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 274 275 sid_to_id(cifs_sb, &parsed.owner, fattr, SIDOWNER); 276 sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP); 277 } 278 279 static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info) 280 { 281 const FILE_DIRECTORY_INFO *fi = info; 282 283 memset(fattr, 0, sizeof(*fattr)); 284 fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes); 285 fattr->cf_eof = le64_to_cpu(fi->EndOfFile); 286 fattr->cf_bytes = le64_to_cpu(fi->AllocationSize); 287 fattr->cf_createtime = le64_to_cpu(fi->CreationTime); 288 fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime); 289 fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime); 290 fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime); 291 } 292 293 void 294 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info, 295 struct cifs_sb_info *cifs_sb) 296 { 297 __dir_info_to_fattr(fattr, info); 298 cifs_fill_common_info(fattr, cifs_sb); 299 } 300 301 static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr, 302 SEARCH_ID_FULL_DIR_INFO *info, 303 struct cifs_sb_info *cifs_sb) 304 { 305 __dir_info_to_fattr(fattr, info); 306 307 /* See MS-FSCC 2.4.19 FileIdFullDirectoryInformation */ 308 if (fattr->cf_cifsattrs & ATTR_REPARSE) 309 fattr->cf_cifstag = le32_to_cpu(info->EaSize); 310 cifs_fill_common_info(fattr, cifs_sb); 311 } 312 313 static void 314 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info, 315 struct cifs_sb_info *cifs_sb) 316 { 317 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj; 318 319 memset(fattr, 0, sizeof(*fattr)); 320 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate, 321 info->LastAccessTime, offset); 322 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate, 323 info->LastWriteTime, offset); 324 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate, 325 info->LastWriteTime, offset); 326 327 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes); 328 fattr->cf_bytes = le32_to_cpu(info->AllocationSize); 329 fattr->cf_eof = le32_to_cpu(info->DataSize); 330 331 cifs_fill_common_info(fattr, cifs_sb); 332 } 333 334 /* BB eventually need to add the following helper function to 335 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when 336 we try to do FindFirst on (NTFS) directory symlinks */ 337 /* 338 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb, 339 unsigned int xid) 340 { 341 __u16 fid; 342 int len; 343 int oplock = 0; 344 int rc; 345 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb); 346 char *tmpbuffer; 347 348 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ, 349 OPEN_REPARSE_POINT, &fid, &oplock, NULL, 350 cifs_sb->local_nls, 351 cifs_remap(cifs_sb); 352 if (!rc) { 353 tmpbuffer = kmalloc(maxpath); 354 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path, 355 tmpbuffer, 356 maxpath -1, 357 fid, 358 cifs_sb->local_nls); 359 if (CIFSSMBClose(xid, ptcon, fid)) { 360 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n"); 361 } 362 } 363 } 364 */ 365 366 static int 367 _initiate_cifs_search(const unsigned int xid, struct file *file, 368 const char *full_path) 369 { 370 __u16 search_flags; 371 int rc = 0; 372 struct cifsFileInfo *cifsFile; 373 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 374 struct tcon_link *tlink = NULL; 375 struct cifs_tcon *tcon; 376 struct TCP_Server_Info *server; 377 378 if (file->private_data == NULL) { 379 tlink = cifs_sb_tlink(cifs_sb); 380 if (IS_ERR(tlink)) 381 return PTR_ERR(tlink); 382 383 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); 384 if (cifsFile == NULL) { 385 rc = -ENOMEM; 386 goto error_exit; 387 } 388 spin_lock_init(&cifsFile->file_info_lock); 389 file->private_data = cifsFile; 390 cifsFile->tlink = cifs_get_tlink(tlink); 391 tcon = tlink_tcon(tlink); 392 } else { 393 cifsFile = file->private_data; 394 tcon = tlink_tcon(cifsFile->tlink); 395 } 396 397 server = tcon->ses->server; 398 399 if (!server->ops->query_dir_first) { 400 rc = -ENOSYS; 401 goto error_exit; 402 } 403 404 cifsFile->invalidHandle = true; 405 cifsFile->srch_inf.endOfSearch = false; 406 407 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos); 408 409 ffirst_retry: 410 /* test for Unix extensions */ 411 /* but now check for them on the share/mount not on the SMB session */ 412 /* if (cap_unix(tcon->ses) { */ 413 if (tcon->unix_ext) 414 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX; 415 else if (tcon->posix_extensions) 416 cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO; 417 else if ((tcon->ses->capabilities & 418 tcon->ses->server->vals->cap_nt_find) == 0) { 419 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD; 420 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { 421 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO; 422 } else /* not srvinos - BB fixme add check for backlevel? */ { 423 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO; 424 } 425 426 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; 427 if (backup_cred(cifs_sb)) 428 search_flags |= CIFS_SEARCH_BACKUP_SEARCH; 429 430 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb, 431 &cifsFile->fid, search_flags, 432 &cifsFile->srch_inf); 433 434 if (rc == 0) 435 cifsFile->invalidHandle = false; 436 /* BB add following call to handle readdir on new NTFS symlink errors 437 else if STATUS_STOPPED_ON_SYMLINK 438 call get_symlink_reparse_path and retry with new path */ 439 else if ((rc == -EOPNOTSUPP) && 440 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { 441 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; 442 goto ffirst_retry; 443 } 444 error_exit: 445 cifs_put_tlink(tlink); 446 return rc; 447 } 448 449 static int 450 initiate_cifs_search(const unsigned int xid, struct file *file, 451 const char *full_path) 452 { 453 int rc, retry_count = 0; 454 455 do { 456 rc = _initiate_cifs_search(xid, file, full_path); 457 /* 458 * If we don't have enough credits to start reading the 459 * directory just try again after short wait. 460 */ 461 if (rc != -EDEADLK) 462 break; 463 464 usleep_range(512, 2048); 465 } while (retry_count++ < 5); 466 467 return rc; 468 } 469 470 /* return length of unicode string in bytes */ 471 static int cifs_unicode_bytelen(const char *str) 472 { 473 int len; 474 const __le16 *ustr = (const __le16 *)str; 475 476 for (len = 0; len <= PATH_MAX; len++) { 477 if (ustr[len] == 0) 478 return len << 1; 479 } 480 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n"); 481 return len << 1; 482 } 483 484 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level) 485 { 486 char *new_entry; 487 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry; 488 489 if (level == SMB_FIND_FILE_INFO_STANDARD) { 490 FIND_FILE_STANDARD_INFO *pfData; 491 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo; 492 493 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 + 494 pfData->FileNameLength; 495 } else { 496 u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset); 497 498 if (old_entry + next_offset < old_entry) { 499 cifs_dbg(VFS, "Invalid offset %u\n", next_offset); 500 return NULL; 501 } 502 new_entry = old_entry + next_offset; 503 } 504 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry); 505 /* validate that new_entry is not past end of SMB */ 506 if (new_entry >= end_of_smb) { 507 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n", 508 new_entry, end_of_smb, old_entry); 509 return NULL; 510 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) && 511 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 > end_of_smb)) 512 || ((level != SMB_FIND_FILE_INFO_STANDARD) && 513 (new_entry + sizeof(FILE_DIRECTORY_INFO) + 1 > end_of_smb))) { 514 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n", 515 new_entry, end_of_smb); 516 return NULL; 517 } else 518 return new_entry; 519 520 } 521 522 struct cifs_dirent { 523 const char *name; 524 size_t namelen; 525 u32 resume_key; 526 u64 ino; 527 }; 528 529 static void cifs_fill_dirent_posix(struct cifs_dirent *de, 530 const struct smb2_posix_info *info) 531 { 532 struct smb2_posix_info_parsed parsed; 533 534 /* payload should have already been checked at this point */ 535 if (posix_info_parse(info, NULL, &parsed) < 0) { 536 cifs_dbg(VFS, "Invalid POSIX info payload\n"); 537 return; 538 } 539 540 de->name = parsed.name; 541 de->namelen = parsed.name_len; 542 de->resume_key = info->Ignored; 543 de->ino = le64_to_cpu(info->Inode); 544 } 545 546 static void cifs_fill_dirent_unix(struct cifs_dirent *de, 547 const FILE_UNIX_INFO *info, bool is_unicode) 548 { 549 de->name = &info->FileName[0]; 550 if (is_unicode) 551 de->namelen = cifs_unicode_bytelen(de->name); 552 else 553 de->namelen = strnlen(de->name, PATH_MAX); 554 de->resume_key = info->ResumeKey; 555 de->ino = le64_to_cpu(info->basic.UniqueId); 556 } 557 558 static void cifs_fill_dirent_dir(struct cifs_dirent *de, 559 const FILE_DIRECTORY_INFO *info) 560 { 561 de->name = &info->FileName[0]; 562 de->namelen = le32_to_cpu(info->FileNameLength); 563 de->resume_key = info->FileIndex; 564 } 565 566 static void cifs_fill_dirent_full(struct cifs_dirent *de, 567 const FILE_FULL_DIRECTORY_INFO *info) 568 { 569 de->name = &info->FileName[0]; 570 de->namelen = le32_to_cpu(info->FileNameLength); 571 de->resume_key = info->FileIndex; 572 } 573 574 static void cifs_fill_dirent_search(struct cifs_dirent *de, 575 const SEARCH_ID_FULL_DIR_INFO *info) 576 { 577 de->name = &info->FileName[0]; 578 de->namelen = le32_to_cpu(info->FileNameLength); 579 de->resume_key = info->FileIndex; 580 de->ino = le64_to_cpu(info->UniqueId); 581 } 582 583 static void cifs_fill_dirent_both(struct cifs_dirent *de, 584 const FILE_BOTH_DIRECTORY_INFO *info) 585 { 586 de->name = &info->FileName[0]; 587 de->namelen = le32_to_cpu(info->FileNameLength); 588 de->resume_key = info->FileIndex; 589 } 590 591 static void cifs_fill_dirent_std(struct cifs_dirent *de, 592 const FIND_FILE_STANDARD_INFO *info) 593 { 594 de->name = &info->FileName[0]; 595 /* one byte length, no endianess conversion */ 596 de->namelen = info->FileNameLength; 597 de->resume_key = info->ResumeKey; 598 } 599 600 static int cifs_fill_dirent(struct cifs_dirent *de, const void *info, 601 u16 level, bool is_unicode) 602 { 603 memset(de, 0, sizeof(*de)); 604 605 switch (level) { 606 case SMB_FIND_FILE_POSIX_INFO: 607 cifs_fill_dirent_posix(de, info); 608 break; 609 case SMB_FIND_FILE_UNIX: 610 cifs_fill_dirent_unix(de, info, is_unicode); 611 break; 612 case SMB_FIND_FILE_DIRECTORY_INFO: 613 cifs_fill_dirent_dir(de, info); 614 break; 615 case SMB_FIND_FILE_FULL_DIRECTORY_INFO: 616 cifs_fill_dirent_full(de, info); 617 break; 618 case SMB_FIND_FILE_ID_FULL_DIR_INFO: 619 cifs_fill_dirent_search(de, info); 620 break; 621 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO: 622 cifs_fill_dirent_both(de, info); 623 break; 624 case SMB_FIND_FILE_INFO_STANDARD: 625 cifs_fill_dirent_std(de, info); 626 break; 627 default: 628 cifs_dbg(FYI, "Unknown findfirst level %d\n", level); 629 return -EINVAL; 630 } 631 632 return 0; 633 } 634 635 #define UNICODE_DOT cpu_to_le16(0x2e) 636 637 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */ 638 static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode) 639 { 640 int rc = 0; 641 642 if (!de->name) 643 return 0; 644 645 if (is_unicode) { 646 __le16 *ufilename = (__le16 *)de->name; 647 if (de->namelen == 2) { 648 /* check for . */ 649 if (ufilename[0] == UNICODE_DOT) 650 rc = 1; 651 } else if (de->namelen == 4) { 652 /* check for .. */ 653 if (ufilename[0] == UNICODE_DOT && 654 ufilename[1] == UNICODE_DOT) 655 rc = 2; 656 } 657 } else /* ASCII */ { 658 if (de->namelen == 1) { 659 if (de->name[0] == '.') 660 rc = 1; 661 } else if (de->namelen == 2) { 662 if (de->name[0] == '.' && de->name[1] == '.') 663 rc = 2; 664 } 665 } 666 667 return rc; 668 } 669 670 /* Check if directory that we are searching has changed so we can decide 671 whether we can use the cached search results from the previous search */ 672 static int is_dir_changed(struct file *file) 673 { 674 struct inode *inode = file_inode(file); 675 struct cifsInodeInfo *cifsInfo = CIFS_I(inode); 676 677 if (cifsInfo->time == 0) 678 return 1; /* directory was changed, perhaps due to unlink */ 679 else 680 return 0; 681 682 } 683 684 static int cifs_save_resume_key(const char *current_entry, 685 struct cifsFileInfo *file_info) 686 { 687 struct cifs_dirent de; 688 int rc; 689 690 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level, 691 file_info->srch_inf.unicode); 692 if (!rc) { 693 file_info->srch_inf.presume_name = de.name; 694 file_info->srch_inf.resume_name_len = de.namelen; 695 file_info->srch_inf.resume_key = de.resume_key; 696 } 697 return rc; 698 } 699 700 /* 701 * Find the corresponding entry in the search. Note that the SMB server returns 702 * search entries for . and .. which complicates logic here if we choose to 703 * parse for them and we do not assume that they are located in the findfirst 704 * return buffer. We start counting in the buffer with entry 2 and increment for 705 * every entry (do not increment for . or .. entry). 706 */ 707 static int 708 find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos, 709 struct file *file, const char *full_path, 710 char **current_entry, int *num_to_ret) 711 { 712 __u16 search_flags; 713 int rc = 0; 714 int pos_in_buf = 0; 715 loff_t first_entry_in_buffer; 716 loff_t index_to_find = pos; 717 struct cifsFileInfo *cfile = file->private_data; 718 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 719 struct TCP_Server_Info *server = tcon->ses->server; 720 /* check if index in the buffer */ 721 722 if (!server->ops->query_dir_first || !server->ops->query_dir_next) 723 return -ENOSYS; 724 725 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL)) 726 return -ENOENT; 727 728 *current_entry = NULL; 729 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry - 730 cfile->srch_inf.entries_in_buffer; 731 732 /* 733 * If first entry in buf is zero then is first buffer 734 * in search response data which means it is likely . and .. 735 * will be in this buffer, although some servers do not return 736 * . and .. for the root of a drive and for those we need 737 * to start two entries earlier. 738 */ 739 740 dump_cifs_file_struct(file, "In fce "); 741 if (((index_to_find < cfile->srch_inf.index_of_last_entry) && 742 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) { 743 /* close and restart search */ 744 cifs_dbg(FYI, "search backing up - close and restart search\n"); 745 spin_lock(&cfile->file_info_lock); 746 if (server->ops->dir_needs_close(cfile)) { 747 cfile->invalidHandle = true; 748 spin_unlock(&cfile->file_info_lock); 749 if (server->ops->close_dir) 750 server->ops->close_dir(xid, tcon, &cfile->fid); 751 } else 752 spin_unlock(&cfile->file_info_lock); 753 if (cfile->srch_inf.ntwrk_buf_start) { 754 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n"); 755 if (cfile->srch_inf.smallBuf) 756 cifs_small_buf_release(cfile->srch_inf. 757 ntwrk_buf_start); 758 else 759 cifs_buf_release(cfile->srch_inf. 760 ntwrk_buf_start); 761 cfile->srch_inf.ntwrk_buf_start = NULL; 762 } 763 rc = initiate_cifs_search(xid, file, full_path); 764 if (rc) { 765 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n", 766 rc); 767 return rc; 768 } 769 /* FindFirst/Next set last_entry to NULL on malformed reply */ 770 if (cfile->srch_inf.last_entry) 771 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); 772 } 773 774 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; 775 if (backup_cred(cifs_sb)) 776 search_flags |= CIFS_SEARCH_BACKUP_SEARCH; 777 778 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) && 779 (rc == 0) && !cfile->srch_inf.endOfSearch) { 780 cifs_dbg(FYI, "calling findnext2\n"); 781 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid, 782 search_flags, 783 &cfile->srch_inf); 784 /* FindFirst/Next set last_entry to NULL on malformed reply */ 785 if (cfile->srch_inf.last_entry) 786 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); 787 if (rc) 788 return -ENOENT; 789 } 790 if (index_to_find < cfile->srch_inf.index_of_last_entry) { 791 /* we found the buffer that contains the entry */ 792 /* scan and find it */ 793 int i; 794 char *cur_ent; 795 char *end_of_smb; 796 797 if (cfile->srch_inf.ntwrk_buf_start == NULL) { 798 cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n"); 799 return -EIO; 800 } 801 802 end_of_smb = cfile->srch_inf.ntwrk_buf_start + 803 server->ops->calc_smb_size( 804 cfile->srch_inf.ntwrk_buf_start); 805 806 cur_ent = cfile->srch_inf.srch_entries_start; 807 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry 808 - cfile->srch_inf.entries_in_buffer; 809 pos_in_buf = index_to_find - first_entry_in_buffer; 810 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf); 811 812 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) { 813 /* go entry by entry figuring out which is first */ 814 cur_ent = nxt_dir_entry(cur_ent, end_of_smb, 815 cfile->srch_inf.info_level); 816 } 817 if ((cur_ent == NULL) && (i < pos_in_buf)) { 818 /* BB fixme - check if we should flag this error */ 819 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n", 820 pos_in_buf, index_to_find, rc); 821 } 822 rc = 0; 823 *current_entry = cur_ent; 824 } else { 825 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n"); 826 return 0; 827 } 828 829 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) { 830 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n"); 831 *num_to_ret = 0; 832 } else 833 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf; 834 835 return rc; 836 } 837 838 static bool emit_cached_dirents(struct cached_dirents *cde, 839 struct dir_context *ctx) 840 { 841 struct cached_dirent *dirent; 842 bool rc; 843 844 list_for_each_entry(dirent, &cde->entries, entry) { 845 /* 846 * Skip all early entries prior to the current lseek() 847 * position. 848 */ 849 if (ctx->pos > dirent->pos) 850 continue; 851 /* 852 * We recorded the current ->pos value for the dirent 853 * when we stored it in the cache. 854 * However, this sequence of ->pos values may have holes 855 * in it, for example dot-dirs returned from the server 856 * are suppressed. 857 * Handle this bu forcing ctx->pos to be the same as the 858 * ->pos of the current dirent we emit from the cache. 859 * This means that when we emit these entries from the cache 860 * we now emit them with the same ->pos value as in the 861 * initial scan. 862 */ 863 ctx->pos = dirent->pos; 864 rc = dir_emit(ctx, dirent->name, dirent->namelen, 865 dirent->fattr.cf_uniqueid, 866 dirent->fattr.cf_dtype); 867 if (!rc) 868 return rc; 869 ctx->pos++; 870 } 871 return true; 872 } 873 874 static void update_cached_dirents_count(struct cached_dirents *cde, 875 struct dir_context *ctx) 876 { 877 if (cde->ctx != ctx) 878 return; 879 if (cde->is_valid || cde->is_failed) 880 return; 881 882 cde->pos++; 883 } 884 885 static void finished_cached_dirents_count(struct cached_dirents *cde, 886 struct dir_context *ctx) 887 { 888 if (cde->ctx != ctx) 889 return; 890 if (cde->is_valid || cde->is_failed) 891 return; 892 if (ctx->pos != cde->pos) 893 return; 894 895 cde->is_valid = 1; 896 } 897 898 static void add_cached_dirent(struct cached_dirents *cde, 899 struct dir_context *ctx, 900 const char *name, int namelen, 901 struct cifs_fattr *fattr) 902 { 903 struct cached_dirent *de; 904 905 if (cde->ctx != ctx) 906 return; 907 if (cde->is_valid || cde->is_failed) 908 return; 909 if (ctx->pos != cde->pos) { 910 cde->is_failed = 1; 911 return; 912 } 913 de = kzalloc(sizeof(*de), GFP_ATOMIC); 914 if (de == NULL) { 915 cde->is_failed = 1; 916 return; 917 } 918 de->namelen = namelen; 919 de->name = kstrndup(name, namelen, GFP_ATOMIC); 920 if (de->name == NULL) { 921 kfree(de); 922 cde->is_failed = 1; 923 return; 924 } 925 de->pos = ctx->pos; 926 927 memcpy(&de->fattr, fattr, sizeof(struct cifs_fattr)); 928 929 list_add_tail(&de->entry, &cde->entries); 930 } 931 932 static bool cifs_dir_emit(struct dir_context *ctx, 933 const char *name, int namelen, 934 struct cifs_fattr *fattr, 935 struct cached_fid *cfid) 936 { 937 bool rc; 938 ino_t ino = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid); 939 940 rc = dir_emit(ctx, name, namelen, ino, fattr->cf_dtype); 941 if (!rc) 942 return rc; 943 944 if (cfid) { 945 mutex_lock(&cfid->dirents.de_mutex); 946 add_cached_dirent(&cfid->dirents, ctx, name, namelen, 947 fattr); 948 mutex_unlock(&cfid->dirents.de_mutex); 949 } 950 951 return rc; 952 } 953 954 static int cifs_filldir(char *find_entry, struct file *file, 955 struct dir_context *ctx, 956 char *scratch_buf, unsigned int max_len, 957 struct cached_fid *cfid) 958 { 959 struct cifsFileInfo *file_info = file->private_data; 960 struct super_block *sb = file_inode(file)->i_sb; 961 struct cifs_sb_info *cifs_sb = CIFS_SB(sb); 962 struct cifs_dirent de = { NULL, }; 963 struct cifs_fattr fattr; 964 struct qstr name; 965 int rc = 0; 966 967 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level, 968 file_info->srch_inf.unicode); 969 if (rc) 970 return rc; 971 972 if (de.namelen > max_len) { 973 cifs_dbg(VFS, "bad search response length %zd past smb end\n", 974 de.namelen); 975 return -EINVAL; 976 } 977 978 /* skip . and .. since we added them first */ 979 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode)) 980 return 0; 981 982 if (file_info->srch_inf.unicode) { 983 struct nls_table *nlt = cifs_sb->local_nls; 984 int map_type; 985 986 map_type = cifs_remap(cifs_sb); 987 name.name = scratch_buf; 988 name.len = 989 cifs_from_utf16((char *)name.name, (__le16 *)de.name, 990 UNICODE_NAME_MAX, 991 min_t(size_t, de.namelen, 992 (size_t)max_len), nlt, map_type); 993 name.len -= nls_nullsize(nlt); 994 } else { 995 name.name = de.name; 996 name.len = de.namelen; 997 } 998 999 switch (file_info->srch_inf.info_level) { 1000 case SMB_FIND_FILE_POSIX_INFO: 1001 cifs_posix_to_fattr(&fattr, 1002 (struct smb2_posix_info *)find_entry, 1003 cifs_sb); 1004 break; 1005 case SMB_FIND_FILE_UNIX: 1006 cifs_unix_basic_to_fattr(&fattr, 1007 &((FILE_UNIX_INFO *)find_entry)->basic, 1008 cifs_sb); 1009 if (S_ISLNK(fattr.cf_mode)) 1010 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; 1011 break; 1012 case SMB_FIND_FILE_INFO_STANDARD: 1013 cifs_std_info_to_fattr(&fattr, 1014 (FIND_FILE_STANDARD_INFO *)find_entry, 1015 cifs_sb); 1016 break; 1017 case SMB_FIND_FILE_ID_FULL_DIR_INFO: 1018 cifs_fulldir_info_to_fattr(&fattr, 1019 (SEARCH_ID_FULL_DIR_INFO *)find_entry, 1020 cifs_sb); 1021 break; 1022 default: 1023 cifs_dir_info_to_fattr(&fattr, 1024 (FILE_DIRECTORY_INFO *)find_entry, 1025 cifs_sb); 1026 break; 1027 } 1028 1029 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { 1030 fattr.cf_uniqueid = de.ino; 1031 } else { 1032 fattr.cf_uniqueid = iunique(sb, ROOT_I); 1033 cifs_autodisable_serverino(cifs_sb); 1034 } 1035 1036 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) && 1037 couldbe_mf_symlink(&fattr)) 1038 /* 1039 * trying to get the type and mode can be slow, 1040 * so just call those regular files for now, and mark 1041 * for reval 1042 */ 1043 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; 1044 1045 cifs_prime_dcache(file_dentry(file), &name, &fattr); 1046 1047 return !cifs_dir_emit(ctx, name.name, name.len, 1048 &fattr, cfid); 1049 } 1050 1051 1052 int cifs_readdir(struct file *file, struct dir_context *ctx) 1053 { 1054 int rc = 0; 1055 unsigned int xid; 1056 int i; 1057 struct tcon_link *tlink = NULL; 1058 struct cifs_tcon *tcon; 1059 struct cifsFileInfo *cifsFile; 1060 char *current_entry; 1061 int num_to_fill = 0; 1062 char *tmp_buf = NULL; 1063 char *end_of_smb; 1064 unsigned int max_len; 1065 const char *full_path; 1066 void *page = alloc_dentry_path(); 1067 struct cached_fid *cfid = NULL; 1068 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 1069 1070 xid = get_xid(); 1071 1072 full_path = build_path_from_dentry(file_dentry(file), page); 1073 if (IS_ERR(full_path)) { 1074 rc = PTR_ERR(full_path); 1075 goto rddir2_exit; 1076 } 1077 1078 if (file->private_data == NULL) { 1079 tlink = cifs_sb_tlink(cifs_sb); 1080 if (IS_ERR(tlink)) 1081 goto cache_not_found; 1082 tcon = tlink_tcon(tlink); 1083 } else { 1084 cifsFile = file->private_data; 1085 tcon = tlink_tcon(cifsFile->tlink); 1086 } 1087 1088 rc = open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); 1089 cifs_put_tlink(tlink); 1090 if (rc) 1091 goto cache_not_found; 1092 1093 mutex_lock(&cfid->dirents.de_mutex); 1094 /* 1095 * If this was reading from the start of the directory 1096 * we need to initialize scanning and storing the 1097 * directory content. 1098 */ 1099 if (ctx->pos == 0 && cfid->dirents.ctx == NULL) { 1100 cfid->dirents.ctx = ctx; 1101 cfid->dirents.pos = 2; 1102 } 1103 /* 1104 * If we already have the entire directory cached then 1105 * we can just serve the cache. 1106 */ 1107 if (cfid->dirents.is_valid) { 1108 if (!dir_emit_dots(file, ctx)) { 1109 mutex_unlock(&cfid->dirents.de_mutex); 1110 goto rddir2_exit; 1111 } 1112 emit_cached_dirents(&cfid->dirents, ctx); 1113 mutex_unlock(&cfid->dirents.de_mutex); 1114 goto rddir2_exit; 1115 } 1116 mutex_unlock(&cfid->dirents.de_mutex); 1117 1118 /* Drop the cache while calling initiate_cifs_search and 1119 * find_cifs_entry in case there will be reconnects during 1120 * query_directory. 1121 */ 1122 close_cached_dir(cfid); 1123 cfid = NULL; 1124 1125 cache_not_found: 1126 /* 1127 * Ensure FindFirst doesn't fail before doing filldir() for '.' and 1128 * '..'. Otherwise we won't be able to notify VFS in case of failure. 1129 */ 1130 if (file->private_data == NULL) { 1131 rc = initiate_cifs_search(xid, file, full_path); 1132 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc); 1133 if (rc) 1134 goto rddir2_exit; 1135 } 1136 1137 if (!dir_emit_dots(file, ctx)) 1138 goto rddir2_exit; 1139 1140 /* 1) If search is active, 1141 is in current search buffer? 1142 if it before then restart search 1143 if after then keep searching till find it */ 1144 cifsFile = file->private_data; 1145 if (cifsFile->srch_inf.endOfSearch) { 1146 if (cifsFile->srch_inf.emptyDir) { 1147 cifs_dbg(FYI, "End of search, empty dir\n"); 1148 rc = 0; 1149 goto rddir2_exit; 1150 } 1151 } /* else { 1152 cifsFile->invalidHandle = true; 1153 tcon->ses->server->close(xid, tcon, &cifsFile->fid); 1154 } */ 1155 1156 tcon = tlink_tcon(cifsFile->tlink); 1157 rc = find_cifs_entry(xid, tcon, ctx->pos, file, full_path, 1158 ¤t_entry, &num_to_fill); 1159 open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); 1160 if (rc) { 1161 cifs_dbg(FYI, "fce error %d\n", rc); 1162 goto rddir2_exit; 1163 } else if (current_entry != NULL) { 1164 cifs_dbg(FYI, "entry %lld found\n", ctx->pos); 1165 } else { 1166 if (cfid) { 1167 mutex_lock(&cfid->dirents.de_mutex); 1168 finished_cached_dirents_count(&cfid->dirents, ctx); 1169 mutex_unlock(&cfid->dirents.de_mutex); 1170 } 1171 cifs_dbg(FYI, "Could not find entry\n"); 1172 goto rddir2_exit; 1173 } 1174 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n", 1175 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start); 1176 max_len = tcon->ses->server->ops->calc_smb_size( 1177 cifsFile->srch_inf.ntwrk_buf_start); 1178 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len; 1179 1180 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL); 1181 if (tmp_buf == NULL) { 1182 rc = -ENOMEM; 1183 goto rddir2_exit; 1184 } 1185 1186 for (i = 0; i < num_to_fill; i++) { 1187 if (current_entry == NULL) { 1188 /* evaluate whether this case is an error */ 1189 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n", 1190 num_to_fill, i); 1191 break; 1192 } 1193 /* 1194 * if buggy server returns . and .. late do we want to 1195 * check for that here? 1196 */ 1197 *tmp_buf = 0; 1198 rc = cifs_filldir(current_entry, file, ctx, 1199 tmp_buf, max_len, cfid); 1200 if (rc) { 1201 if (rc > 0) 1202 rc = 0; 1203 break; 1204 } 1205 1206 ctx->pos++; 1207 if (cfid) { 1208 mutex_lock(&cfid->dirents.de_mutex); 1209 update_cached_dirents_count(&cfid->dirents, ctx); 1210 mutex_unlock(&cfid->dirents.de_mutex); 1211 } 1212 1213 if (ctx->pos == 1214 cifsFile->srch_inf.index_of_last_entry) { 1215 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n", 1216 ctx->pos, tmp_buf); 1217 cifs_save_resume_key(current_entry, cifsFile); 1218 break; 1219 } 1220 current_entry = 1221 nxt_dir_entry(current_entry, end_of_smb, 1222 cifsFile->srch_inf.info_level); 1223 } 1224 kfree(tmp_buf); 1225 1226 rddir2_exit: 1227 if (cfid) 1228 close_cached_dir(cfid); 1229 free_dentry_path(page); 1230 free_xid(xid); 1231 return rc; 1232 } 1233