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