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 0: 147 return true; 148 } 149 return false; 150 } 151 152 static void 153 cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) 154 { 155 fattr->cf_uid = cifs_sb->ctx->linux_uid; 156 fattr->cf_gid = cifs_sb->ctx->linux_gid; 157 158 /* 159 * The IO_REPARSE_TAG_LX_ tags originally were used by WSL but they 160 * are preferred by the Linux client in some cases since, unlike 161 * the NFS reparse tag (or EAs), they don't require an extra query 162 * to determine which type of special file they represent. 163 * TODO: go through all documented reparse tags to see if we can 164 * reasonably map some of them to directories vs. files vs. symlinks 165 */ 166 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { 167 fattr->cf_mode = S_IFDIR | cifs_sb->ctx->dir_mode; 168 fattr->cf_dtype = DT_DIR; 169 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_SYMLINK) { 170 fattr->cf_mode |= S_IFLNK | cifs_sb->ctx->file_mode; 171 fattr->cf_dtype = DT_LNK; 172 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_FIFO) { 173 fattr->cf_mode |= S_IFIFO | cifs_sb->ctx->file_mode; 174 fattr->cf_dtype = DT_FIFO; 175 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_AF_UNIX) { 176 fattr->cf_mode |= S_IFSOCK | cifs_sb->ctx->file_mode; 177 fattr->cf_dtype = DT_SOCK; 178 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_CHR) { 179 fattr->cf_mode |= S_IFCHR | cifs_sb->ctx->file_mode; 180 fattr->cf_dtype = DT_CHR; 181 } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_BLK) { 182 fattr->cf_mode |= S_IFBLK | cifs_sb->ctx->file_mode; 183 fattr->cf_dtype = DT_BLK; 184 } else { /* TODO: should we mark some other reparse points (like DFSR) as directories? */ 185 fattr->cf_mode = S_IFREG | cifs_sb->ctx->file_mode; 186 fattr->cf_dtype = DT_REG; 187 } 188 189 /* 190 * We need to revalidate it further to make a decision about whether it 191 * is a symbolic link, DFS referral or a reparse point with a direct 192 * access like junctions, deduplicated files, NFS symlinks. 193 */ 194 if (reparse_file_needs_reval(fattr)) 195 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 196 197 /* non-unix readdir doesn't provide nlink */ 198 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; 199 200 if (fattr->cf_cifsattrs & ATTR_READONLY) 201 fattr->cf_mode &= ~S_IWUGO; 202 203 /* 204 * We of course don't get ACL info in FIND_FIRST/NEXT results, so 205 * mark it for revalidation so that "ls -l" will look right. It might 206 * be super-slow, but if we don't do this then the ownership of files 207 * may look wrong since the inodes may not have timed out by the time 208 * "ls" does a stat() call on them. 209 */ 210 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) || 211 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID)) 212 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 213 214 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL && 215 fattr->cf_cifsattrs & ATTR_SYSTEM) { 216 if (fattr->cf_eof == 0) { 217 fattr->cf_mode &= ~S_IFMT; 218 fattr->cf_mode |= S_IFIFO; 219 fattr->cf_dtype = DT_FIFO; 220 } else { 221 /* 222 * trying to get the type and mode via SFU can be slow, 223 * so just call those regular files for now, and mark 224 * for reval 225 */ 226 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 227 } 228 } 229 } 230 231 /* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */ 232 static void 233 cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info, 234 struct cifs_sb_info *cifs_sb) 235 { 236 struct smb2_posix_info_parsed parsed; 237 238 posix_info_parse(info, NULL, &parsed); 239 240 memset(fattr, 0, sizeof(*fattr)); 241 fattr->cf_uniqueid = le64_to_cpu(info->Inode); 242 fattr->cf_bytes = le64_to_cpu(info->AllocationSize); 243 fattr->cf_eof = le64_to_cpu(info->EndOfFile); 244 245 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime); 246 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime); 247 fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime); 248 249 fattr->cf_nlink = le32_to_cpu(info->HardLinks); 250 fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes); 251 252 /* 253 * Since we set the inode type below we need to mask off 254 * to avoid strange results if bits set above. 255 * XXX: why not make server&client use the type bits? 256 */ 257 fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT; 258 259 cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n", 260 le32_to_cpu(info->DeviceId), 261 le32_to_cpu(info->ReparseTag), 262 le32_to_cpu(info->Mode)); 263 264 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { 265 fattr->cf_mode |= S_IFDIR; 266 fattr->cf_dtype = DT_DIR; 267 } else { 268 /* 269 * mark anything that is not a dir as regular 270 * file. special files should have the REPARSE 271 * attribute and will be marked as needing revaluation 272 */ 273 fattr->cf_mode |= S_IFREG; 274 fattr->cf_dtype = DT_REG; 275 } 276 277 if (reparse_file_needs_reval(fattr)) 278 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; 279 280 sid_to_id(cifs_sb, &parsed.owner, fattr, SIDOWNER); 281 sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP); 282 } 283 284 static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info) 285 { 286 const FILE_DIRECTORY_INFO *fi = info; 287 288 memset(fattr, 0, sizeof(*fattr)); 289 fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes); 290 fattr->cf_eof = le64_to_cpu(fi->EndOfFile); 291 fattr->cf_bytes = le64_to_cpu(fi->AllocationSize); 292 fattr->cf_createtime = le64_to_cpu(fi->CreationTime); 293 fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime); 294 fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime); 295 fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime); 296 } 297 298 void 299 cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info, 300 struct cifs_sb_info *cifs_sb) 301 { 302 __dir_info_to_fattr(fattr, info); 303 cifs_fill_common_info(fattr, cifs_sb); 304 } 305 306 static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr, 307 SEARCH_ID_FULL_DIR_INFO *info, 308 struct cifs_sb_info *cifs_sb) 309 { 310 __dir_info_to_fattr(fattr, info); 311 312 /* See MS-FSCC 2.4.19 FileIdFullDirectoryInformation */ 313 if (fattr->cf_cifsattrs & ATTR_REPARSE) 314 fattr->cf_cifstag = le32_to_cpu(info->EaSize); 315 cifs_fill_common_info(fattr, cifs_sb); 316 } 317 318 static void 319 cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info, 320 struct cifs_sb_info *cifs_sb) 321 { 322 int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj; 323 324 memset(fattr, 0, sizeof(*fattr)); 325 fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate, 326 info->LastAccessTime, offset); 327 fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate, 328 info->LastWriteTime, offset); 329 fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate, 330 info->LastWriteTime, offset); 331 332 fattr->cf_cifsattrs = le16_to_cpu(info->Attributes); 333 fattr->cf_bytes = le32_to_cpu(info->AllocationSize); 334 fattr->cf_eof = le32_to_cpu(info->DataSize); 335 336 cifs_fill_common_info(fattr, cifs_sb); 337 } 338 339 /* BB eventually need to add the following helper function to 340 resolve NT_STATUS_STOPPED_ON_SYMLINK return code when 341 we try to do FindFirst on (NTFS) directory symlinks */ 342 /* 343 int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb, 344 unsigned int xid) 345 { 346 __u16 fid; 347 int len; 348 int oplock = 0; 349 int rc; 350 struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb); 351 char *tmpbuffer; 352 353 rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ, 354 OPEN_REPARSE_POINT, &fid, &oplock, NULL, 355 cifs_sb->local_nls, 356 cifs_remap(cifs_sb); 357 if (!rc) { 358 tmpbuffer = kmalloc(maxpath); 359 rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path, 360 tmpbuffer, 361 maxpath -1, 362 fid, 363 cifs_sb->local_nls); 364 if (CIFSSMBClose(xid, ptcon, fid)) { 365 cifs_dbg(FYI, "Error closing temporary reparsepoint open\n"); 366 } 367 } 368 } 369 */ 370 371 static int 372 _initiate_cifs_search(const unsigned int xid, struct file *file, 373 const char *full_path) 374 { 375 __u16 search_flags; 376 int rc = 0; 377 struct cifsFileInfo *cifsFile; 378 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 379 struct tcon_link *tlink = NULL; 380 struct cifs_tcon *tcon; 381 struct TCP_Server_Info *server; 382 383 if (file->private_data == NULL) { 384 tlink = cifs_sb_tlink(cifs_sb); 385 if (IS_ERR(tlink)) 386 return PTR_ERR(tlink); 387 388 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); 389 if (cifsFile == NULL) { 390 rc = -ENOMEM; 391 goto error_exit; 392 } 393 spin_lock_init(&cifsFile->file_info_lock); 394 file->private_data = cifsFile; 395 cifsFile->tlink = cifs_get_tlink(tlink); 396 tcon = tlink_tcon(tlink); 397 } else { 398 cifsFile = file->private_data; 399 tcon = tlink_tcon(cifsFile->tlink); 400 } 401 402 server = tcon->ses->server; 403 404 if (!server->ops->query_dir_first) { 405 rc = -ENOSYS; 406 goto error_exit; 407 } 408 409 cifsFile->invalidHandle = true; 410 cifsFile->srch_inf.endOfSearch = false; 411 412 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos); 413 414 ffirst_retry: 415 /* test for Unix extensions */ 416 /* but now check for them on the share/mount not on the SMB session */ 417 /* if (cap_unix(tcon->ses) { */ 418 if (tcon->unix_ext) 419 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX; 420 else if (tcon->posix_extensions) 421 cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO; 422 else if ((tcon->ses->capabilities & 423 tcon->ses->server->vals->cap_nt_find) == 0) { 424 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD; 425 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { 426 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO; 427 } else /* not srvinos - BB fixme add check for backlevel? */ { 428 cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO; 429 } 430 431 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; 432 if (backup_cred(cifs_sb)) 433 search_flags |= CIFS_SEARCH_BACKUP_SEARCH; 434 435 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb, 436 &cifsFile->fid, search_flags, 437 &cifsFile->srch_inf); 438 439 if (rc == 0) 440 cifsFile->invalidHandle = false; 441 /* BB add following call to handle readdir on new NTFS symlink errors 442 else if STATUS_STOPPED_ON_SYMLINK 443 call get_symlink_reparse_path and retry with new path */ 444 else if ((rc == -EOPNOTSUPP) && 445 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { 446 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; 447 goto ffirst_retry; 448 } 449 error_exit: 450 cifs_put_tlink(tlink); 451 return rc; 452 } 453 454 static int 455 initiate_cifs_search(const unsigned int xid, struct file *file, 456 const char *full_path) 457 { 458 int rc, retry_count = 0; 459 460 do { 461 rc = _initiate_cifs_search(xid, file, full_path); 462 /* 463 * If we don't have enough credits to start reading the 464 * directory just try again after short wait. 465 */ 466 if (rc != -EDEADLK) 467 break; 468 469 usleep_range(512, 2048); 470 } while (retry_count++ < 5); 471 472 return rc; 473 } 474 475 /* return length of unicode string in bytes */ 476 static int cifs_unicode_bytelen(const char *str) 477 { 478 int len; 479 const __le16 *ustr = (const __le16 *)str; 480 481 for (len = 0; len <= PATH_MAX; len++) { 482 if (ustr[len] == 0) 483 return len << 1; 484 } 485 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n"); 486 return len << 1; 487 } 488 489 static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level) 490 { 491 char *new_entry; 492 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry; 493 494 if (level == SMB_FIND_FILE_INFO_STANDARD) { 495 FIND_FILE_STANDARD_INFO *pfData; 496 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo; 497 498 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 + 499 pfData->FileNameLength; 500 } else { 501 u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset); 502 503 if (old_entry + next_offset < old_entry) { 504 cifs_dbg(VFS, "Invalid offset %u\n", next_offset); 505 return NULL; 506 } 507 new_entry = old_entry + next_offset; 508 } 509 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry); 510 /* validate that new_entry is not past end of SMB */ 511 if (new_entry >= end_of_smb) { 512 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n", 513 new_entry, end_of_smb, old_entry); 514 return NULL; 515 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) && 516 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 > end_of_smb)) 517 || ((level != SMB_FIND_FILE_INFO_STANDARD) && 518 (new_entry + sizeof(FILE_DIRECTORY_INFO) + 1 > end_of_smb))) { 519 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n", 520 new_entry, end_of_smb); 521 return NULL; 522 } else 523 return new_entry; 524 525 } 526 527 struct cifs_dirent { 528 const char *name; 529 size_t namelen; 530 u32 resume_key; 531 u64 ino; 532 }; 533 534 static void cifs_fill_dirent_posix(struct cifs_dirent *de, 535 const struct smb2_posix_info *info) 536 { 537 struct smb2_posix_info_parsed parsed; 538 539 /* payload should have already been checked at this point */ 540 if (posix_info_parse(info, NULL, &parsed) < 0) { 541 cifs_dbg(VFS, "Invalid POSIX info payload\n"); 542 return; 543 } 544 545 de->name = parsed.name; 546 de->namelen = parsed.name_len; 547 de->resume_key = info->Ignored; 548 de->ino = le64_to_cpu(info->Inode); 549 } 550 551 static void cifs_fill_dirent_unix(struct cifs_dirent *de, 552 const FILE_UNIX_INFO *info, bool is_unicode) 553 { 554 de->name = &info->FileName[0]; 555 if (is_unicode) 556 de->namelen = cifs_unicode_bytelen(de->name); 557 else 558 de->namelen = strnlen(de->name, PATH_MAX); 559 de->resume_key = info->ResumeKey; 560 de->ino = le64_to_cpu(info->basic.UniqueId); 561 } 562 563 static void cifs_fill_dirent_dir(struct cifs_dirent *de, 564 const FILE_DIRECTORY_INFO *info) 565 { 566 de->name = &info->FileName[0]; 567 de->namelen = le32_to_cpu(info->FileNameLength); 568 de->resume_key = info->FileIndex; 569 } 570 571 static void cifs_fill_dirent_full(struct cifs_dirent *de, 572 const FILE_FULL_DIRECTORY_INFO *info) 573 { 574 de->name = &info->FileName[0]; 575 de->namelen = le32_to_cpu(info->FileNameLength); 576 de->resume_key = info->FileIndex; 577 } 578 579 static void cifs_fill_dirent_search(struct cifs_dirent *de, 580 const SEARCH_ID_FULL_DIR_INFO *info) 581 { 582 de->name = &info->FileName[0]; 583 de->namelen = le32_to_cpu(info->FileNameLength); 584 de->resume_key = info->FileIndex; 585 de->ino = le64_to_cpu(info->UniqueId); 586 } 587 588 static void cifs_fill_dirent_both(struct cifs_dirent *de, 589 const FILE_BOTH_DIRECTORY_INFO *info) 590 { 591 de->name = &info->FileName[0]; 592 de->namelen = le32_to_cpu(info->FileNameLength); 593 de->resume_key = info->FileIndex; 594 } 595 596 static void cifs_fill_dirent_std(struct cifs_dirent *de, 597 const FIND_FILE_STANDARD_INFO *info) 598 { 599 de->name = &info->FileName[0]; 600 /* one byte length, no endianess conversion */ 601 de->namelen = info->FileNameLength; 602 de->resume_key = info->ResumeKey; 603 } 604 605 static int cifs_fill_dirent(struct cifs_dirent *de, const void *info, 606 u16 level, bool is_unicode) 607 { 608 memset(de, 0, sizeof(*de)); 609 610 switch (level) { 611 case SMB_FIND_FILE_POSIX_INFO: 612 cifs_fill_dirent_posix(de, info); 613 break; 614 case SMB_FIND_FILE_UNIX: 615 cifs_fill_dirent_unix(de, info, is_unicode); 616 break; 617 case SMB_FIND_FILE_DIRECTORY_INFO: 618 cifs_fill_dirent_dir(de, info); 619 break; 620 case SMB_FIND_FILE_FULL_DIRECTORY_INFO: 621 cifs_fill_dirent_full(de, info); 622 break; 623 case SMB_FIND_FILE_ID_FULL_DIR_INFO: 624 cifs_fill_dirent_search(de, info); 625 break; 626 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO: 627 cifs_fill_dirent_both(de, info); 628 break; 629 case SMB_FIND_FILE_INFO_STANDARD: 630 cifs_fill_dirent_std(de, info); 631 break; 632 default: 633 cifs_dbg(FYI, "Unknown findfirst level %d\n", level); 634 return -EINVAL; 635 } 636 637 return 0; 638 } 639 640 #define UNICODE_DOT cpu_to_le16(0x2e) 641 642 /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */ 643 static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode) 644 { 645 int rc = 0; 646 647 if (!de->name) 648 return 0; 649 650 if (is_unicode) { 651 __le16 *ufilename = (__le16 *)de->name; 652 if (de->namelen == 2) { 653 /* check for . */ 654 if (ufilename[0] == UNICODE_DOT) 655 rc = 1; 656 } else if (de->namelen == 4) { 657 /* check for .. */ 658 if (ufilename[0] == UNICODE_DOT && 659 ufilename[1] == UNICODE_DOT) 660 rc = 2; 661 } 662 } else /* ASCII */ { 663 if (de->namelen == 1) { 664 if (de->name[0] == '.') 665 rc = 1; 666 } else if (de->namelen == 2) { 667 if (de->name[0] == '.' && de->name[1] == '.') 668 rc = 2; 669 } 670 } 671 672 return rc; 673 } 674 675 /* Check if directory that we are searching has changed so we can decide 676 whether we can use the cached search results from the previous search */ 677 static int is_dir_changed(struct file *file) 678 { 679 struct inode *inode = file_inode(file); 680 struct cifsInodeInfo *cifsInfo = CIFS_I(inode); 681 682 if (cifsInfo->time == 0) 683 return 1; /* directory was changed, perhaps due to unlink */ 684 else 685 return 0; 686 687 } 688 689 static int cifs_save_resume_key(const char *current_entry, 690 struct cifsFileInfo *file_info) 691 { 692 struct cifs_dirent de; 693 int rc; 694 695 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level, 696 file_info->srch_inf.unicode); 697 if (!rc) { 698 file_info->srch_inf.presume_name = de.name; 699 file_info->srch_inf.resume_name_len = de.namelen; 700 file_info->srch_inf.resume_key = de.resume_key; 701 } 702 return rc; 703 } 704 705 /* 706 * Find the corresponding entry in the search. Note that the SMB server returns 707 * search entries for . and .. which complicates logic here if we choose to 708 * parse for them and we do not assume that they are located in the findfirst 709 * return buffer. We start counting in the buffer with entry 2 and increment for 710 * every entry (do not increment for . or .. entry). 711 */ 712 static int 713 find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos, 714 struct file *file, const char *full_path, 715 char **current_entry, int *num_to_ret) 716 { 717 __u16 search_flags; 718 int rc = 0; 719 int pos_in_buf = 0; 720 loff_t first_entry_in_buffer; 721 loff_t index_to_find = pos; 722 struct cifsFileInfo *cfile = file->private_data; 723 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 724 struct TCP_Server_Info *server = tcon->ses->server; 725 /* check if index in the buffer */ 726 727 if (!server->ops->query_dir_first || !server->ops->query_dir_next) 728 return -ENOSYS; 729 730 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL)) 731 return -ENOENT; 732 733 *current_entry = NULL; 734 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry - 735 cfile->srch_inf.entries_in_buffer; 736 737 /* 738 * If first entry in buf is zero then is first buffer 739 * in search response data which means it is likely . and .. 740 * will be in this buffer, although some servers do not return 741 * . and .. for the root of a drive and for those we need 742 * to start two entries earlier. 743 */ 744 745 dump_cifs_file_struct(file, "In fce "); 746 if (((index_to_find < cfile->srch_inf.index_of_last_entry) && 747 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) { 748 /* close and restart search */ 749 cifs_dbg(FYI, "search backing up - close and restart search\n"); 750 spin_lock(&cfile->file_info_lock); 751 if (server->ops->dir_needs_close(cfile)) { 752 cfile->invalidHandle = true; 753 spin_unlock(&cfile->file_info_lock); 754 if (server->ops->close_dir) 755 server->ops->close_dir(xid, tcon, &cfile->fid); 756 } else 757 spin_unlock(&cfile->file_info_lock); 758 if (cfile->srch_inf.ntwrk_buf_start) { 759 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n"); 760 if (cfile->srch_inf.smallBuf) 761 cifs_small_buf_release(cfile->srch_inf. 762 ntwrk_buf_start); 763 else 764 cifs_buf_release(cfile->srch_inf. 765 ntwrk_buf_start); 766 cfile->srch_inf.ntwrk_buf_start = NULL; 767 } 768 rc = initiate_cifs_search(xid, file, full_path); 769 if (rc) { 770 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n", 771 rc); 772 return rc; 773 } 774 /* FindFirst/Next set last_entry to NULL on malformed reply */ 775 if (cfile->srch_inf.last_entry) 776 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); 777 } 778 779 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; 780 if (backup_cred(cifs_sb)) 781 search_flags |= CIFS_SEARCH_BACKUP_SEARCH; 782 783 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) && 784 (rc == 0) && !cfile->srch_inf.endOfSearch) { 785 cifs_dbg(FYI, "calling findnext2\n"); 786 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid, 787 search_flags, 788 &cfile->srch_inf); 789 /* FindFirst/Next set last_entry to NULL on malformed reply */ 790 if (cfile->srch_inf.last_entry) 791 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); 792 if (rc) 793 return -ENOENT; 794 } 795 if (index_to_find < cfile->srch_inf.index_of_last_entry) { 796 /* we found the buffer that contains the entry */ 797 /* scan and find it */ 798 int i; 799 char *cur_ent; 800 char *end_of_smb; 801 802 if (cfile->srch_inf.ntwrk_buf_start == NULL) { 803 cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n"); 804 return -EIO; 805 } 806 807 end_of_smb = cfile->srch_inf.ntwrk_buf_start + 808 server->ops->calc_smb_size( 809 cfile->srch_inf.ntwrk_buf_start); 810 811 cur_ent = cfile->srch_inf.srch_entries_start; 812 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry 813 - cfile->srch_inf.entries_in_buffer; 814 pos_in_buf = index_to_find - first_entry_in_buffer; 815 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf); 816 817 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) { 818 /* go entry by entry figuring out which is first */ 819 cur_ent = nxt_dir_entry(cur_ent, end_of_smb, 820 cfile->srch_inf.info_level); 821 } 822 if ((cur_ent == NULL) && (i < pos_in_buf)) { 823 /* BB fixme - check if we should flag this error */ 824 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n", 825 pos_in_buf, index_to_find, rc); 826 } 827 rc = 0; 828 *current_entry = cur_ent; 829 } else { 830 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n"); 831 return 0; 832 } 833 834 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) { 835 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n"); 836 *num_to_ret = 0; 837 } else 838 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf; 839 840 return rc; 841 } 842 843 static bool emit_cached_dirents(struct cached_dirents *cde, 844 struct dir_context *ctx) 845 { 846 struct cached_dirent *dirent; 847 bool rc; 848 849 list_for_each_entry(dirent, &cde->entries, entry) { 850 /* 851 * Skip all early entries prior to the current lseek() 852 * position. 853 */ 854 if (ctx->pos > dirent->pos) 855 continue; 856 /* 857 * We recorded the current ->pos value for the dirent 858 * when we stored it in the cache. 859 * However, this sequence of ->pos values may have holes 860 * in it, for example dot-dirs returned from the server 861 * are suppressed. 862 * Handle this bu forcing ctx->pos to be the same as the 863 * ->pos of the current dirent we emit from the cache. 864 * This means that when we emit these entries from the cache 865 * we now emit them with the same ->pos value as in the 866 * initial scan. 867 */ 868 ctx->pos = dirent->pos; 869 rc = dir_emit(ctx, dirent->name, dirent->namelen, 870 dirent->fattr.cf_uniqueid, 871 dirent->fattr.cf_dtype); 872 if (!rc) 873 return rc; 874 ctx->pos++; 875 } 876 return true; 877 } 878 879 static void update_cached_dirents_count(struct cached_dirents *cde, 880 struct dir_context *ctx) 881 { 882 if (cde->ctx != ctx) 883 return; 884 if (cde->is_valid || cde->is_failed) 885 return; 886 887 cde->pos++; 888 } 889 890 static void finished_cached_dirents_count(struct cached_dirents *cde, 891 struct dir_context *ctx) 892 { 893 if (cde->ctx != ctx) 894 return; 895 if (cde->is_valid || cde->is_failed) 896 return; 897 if (ctx->pos != cde->pos) 898 return; 899 900 cde->is_valid = 1; 901 } 902 903 static void add_cached_dirent(struct cached_dirents *cde, 904 struct dir_context *ctx, 905 const char *name, int namelen, 906 struct cifs_fattr *fattr) 907 { 908 struct cached_dirent *de; 909 910 if (cde->ctx != ctx) 911 return; 912 if (cde->is_valid || cde->is_failed) 913 return; 914 if (ctx->pos != cde->pos) { 915 cde->is_failed = 1; 916 return; 917 } 918 de = kzalloc(sizeof(*de), GFP_ATOMIC); 919 if (de == NULL) { 920 cde->is_failed = 1; 921 return; 922 } 923 de->namelen = namelen; 924 de->name = kstrndup(name, namelen, GFP_ATOMIC); 925 if (de->name == NULL) { 926 kfree(de); 927 cde->is_failed = 1; 928 return; 929 } 930 de->pos = ctx->pos; 931 932 memcpy(&de->fattr, fattr, sizeof(struct cifs_fattr)); 933 934 list_add_tail(&de->entry, &cde->entries); 935 } 936 937 static bool cifs_dir_emit(struct dir_context *ctx, 938 const char *name, int namelen, 939 struct cifs_fattr *fattr, 940 struct cached_fid *cfid) 941 { 942 bool rc; 943 ino_t ino = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid); 944 945 rc = dir_emit(ctx, name, namelen, ino, fattr->cf_dtype); 946 if (!rc) 947 return rc; 948 949 if (cfid) { 950 mutex_lock(&cfid->dirents.de_mutex); 951 add_cached_dirent(&cfid->dirents, ctx, name, namelen, 952 fattr); 953 mutex_unlock(&cfid->dirents.de_mutex); 954 } 955 956 return rc; 957 } 958 959 static int cifs_filldir(char *find_entry, struct file *file, 960 struct dir_context *ctx, 961 char *scratch_buf, unsigned int max_len, 962 struct cached_fid *cfid) 963 { 964 struct cifsFileInfo *file_info = file->private_data; 965 struct super_block *sb = file_inode(file)->i_sb; 966 struct cifs_sb_info *cifs_sb = CIFS_SB(sb); 967 struct cifs_dirent de = { NULL, }; 968 struct cifs_fattr fattr; 969 struct qstr name; 970 int rc = 0; 971 972 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level, 973 file_info->srch_inf.unicode); 974 if (rc) 975 return rc; 976 977 if (de.namelen > max_len) { 978 cifs_dbg(VFS, "bad search response length %zd past smb end\n", 979 de.namelen); 980 return -EINVAL; 981 } 982 983 /* skip . and .. since we added them first */ 984 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode)) 985 return 0; 986 987 if (file_info->srch_inf.unicode) { 988 struct nls_table *nlt = cifs_sb->local_nls; 989 int map_type; 990 991 map_type = cifs_remap(cifs_sb); 992 name.name = scratch_buf; 993 name.len = 994 cifs_from_utf16((char *)name.name, (__le16 *)de.name, 995 UNICODE_NAME_MAX, 996 min_t(size_t, de.namelen, 997 (size_t)max_len), nlt, map_type); 998 name.len -= nls_nullsize(nlt); 999 } else { 1000 name.name = de.name; 1001 name.len = de.namelen; 1002 } 1003 1004 switch (file_info->srch_inf.info_level) { 1005 case SMB_FIND_FILE_POSIX_INFO: 1006 cifs_posix_to_fattr(&fattr, 1007 (struct smb2_posix_info *)find_entry, 1008 cifs_sb); 1009 break; 1010 case SMB_FIND_FILE_UNIX: 1011 cifs_unix_basic_to_fattr(&fattr, 1012 &((FILE_UNIX_INFO *)find_entry)->basic, 1013 cifs_sb); 1014 if (S_ISLNK(fattr.cf_mode)) 1015 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; 1016 break; 1017 case SMB_FIND_FILE_INFO_STANDARD: 1018 cifs_std_info_to_fattr(&fattr, 1019 (FIND_FILE_STANDARD_INFO *)find_entry, 1020 cifs_sb); 1021 break; 1022 case SMB_FIND_FILE_ID_FULL_DIR_INFO: 1023 cifs_fulldir_info_to_fattr(&fattr, 1024 (SEARCH_ID_FULL_DIR_INFO *)find_entry, 1025 cifs_sb); 1026 break; 1027 default: 1028 cifs_dir_info_to_fattr(&fattr, 1029 (FILE_DIRECTORY_INFO *)find_entry, 1030 cifs_sb); 1031 break; 1032 } 1033 1034 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { 1035 fattr.cf_uniqueid = de.ino; 1036 } else { 1037 fattr.cf_uniqueid = iunique(sb, ROOT_I); 1038 cifs_autodisable_serverino(cifs_sb); 1039 } 1040 1041 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) && 1042 couldbe_mf_symlink(&fattr)) 1043 /* 1044 * trying to get the type and mode can be slow, 1045 * so just call those regular files for now, and mark 1046 * for reval 1047 */ 1048 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; 1049 1050 cifs_prime_dcache(file_dentry(file), &name, &fattr); 1051 1052 return !cifs_dir_emit(ctx, name.name, name.len, 1053 &fattr, cfid); 1054 } 1055 1056 1057 int cifs_readdir(struct file *file, struct dir_context *ctx) 1058 { 1059 int rc = 0; 1060 unsigned int xid; 1061 int i; 1062 struct tcon_link *tlink = NULL; 1063 struct cifs_tcon *tcon; 1064 struct cifsFileInfo *cifsFile; 1065 char *current_entry; 1066 int num_to_fill = 0; 1067 char *tmp_buf = NULL; 1068 char *end_of_smb; 1069 unsigned int max_len; 1070 const char *full_path; 1071 void *page = alloc_dentry_path(); 1072 struct cached_fid *cfid = NULL; 1073 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); 1074 1075 xid = get_xid(); 1076 1077 full_path = build_path_from_dentry(file_dentry(file), page); 1078 if (IS_ERR(full_path)) { 1079 rc = PTR_ERR(full_path); 1080 goto rddir2_exit; 1081 } 1082 1083 if (file->private_data == NULL) { 1084 tlink = cifs_sb_tlink(cifs_sb); 1085 if (IS_ERR(tlink)) 1086 goto cache_not_found; 1087 tcon = tlink_tcon(tlink); 1088 } else { 1089 cifsFile = file->private_data; 1090 tcon = tlink_tcon(cifsFile->tlink); 1091 } 1092 1093 rc = open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); 1094 cifs_put_tlink(tlink); 1095 if (rc) 1096 goto cache_not_found; 1097 1098 mutex_lock(&cfid->dirents.de_mutex); 1099 /* 1100 * If this was reading from the start of the directory 1101 * we need to initialize scanning and storing the 1102 * directory content. 1103 */ 1104 if (ctx->pos == 0 && cfid->dirents.ctx == NULL) { 1105 cfid->dirents.ctx = ctx; 1106 cfid->dirents.pos = 2; 1107 } 1108 /* 1109 * If we already have the entire directory cached then 1110 * we can just serve the cache. 1111 */ 1112 if (cfid->dirents.is_valid) { 1113 if (!dir_emit_dots(file, ctx)) { 1114 mutex_unlock(&cfid->dirents.de_mutex); 1115 goto rddir2_exit; 1116 } 1117 emit_cached_dirents(&cfid->dirents, ctx); 1118 mutex_unlock(&cfid->dirents.de_mutex); 1119 goto rddir2_exit; 1120 } 1121 mutex_unlock(&cfid->dirents.de_mutex); 1122 1123 /* Drop the cache while calling initiate_cifs_search and 1124 * find_cifs_entry in case there will be reconnects during 1125 * query_directory. 1126 */ 1127 close_cached_dir(cfid); 1128 cfid = NULL; 1129 1130 cache_not_found: 1131 /* 1132 * Ensure FindFirst doesn't fail before doing filldir() for '.' and 1133 * '..'. Otherwise we won't be able to notify VFS in case of failure. 1134 */ 1135 if (file->private_data == NULL) { 1136 rc = initiate_cifs_search(xid, file, full_path); 1137 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc); 1138 if (rc) 1139 goto rddir2_exit; 1140 } 1141 1142 if (!dir_emit_dots(file, ctx)) 1143 goto rddir2_exit; 1144 1145 /* 1) If search is active, 1146 is in current search buffer? 1147 if it before then restart search 1148 if after then keep searching till find it */ 1149 cifsFile = file->private_data; 1150 if (cifsFile->srch_inf.endOfSearch) { 1151 if (cifsFile->srch_inf.emptyDir) { 1152 cifs_dbg(FYI, "End of search, empty dir\n"); 1153 rc = 0; 1154 goto rddir2_exit; 1155 } 1156 } /* else { 1157 cifsFile->invalidHandle = true; 1158 tcon->ses->server->close(xid, tcon, &cifsFile->fid); 1159 } */ 1160 1161 tcon = tlink_tcon(cifsFile->tlink); 1162 rc = find_cifs_entry(xid, tcon, ctx->pos, file, full_path, 1163 ¤t_entry, &num_to_fill); 1164 open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); 1165 if (rc) { 1166 cifs_dbg(FYI, "fce error %d\n", rc); 1167 goto rddir2_exit; 1168 } else if (current_entry != NULL) { 1169 cifs_dbg(FYI, "entry %lld found\n", ctx->pos); 1170 } else { 1171 if (cfid) { 1172 mutex_lock(&cfid->dirents.de_mutex); 1173 finished_cached_dirents_count(&cfid->dirents, ctx); 1174 mutex_unlock(&cfid->dirents.de_mutex); 1175 } 1176 cifs_dbg(FYI, "Could not find entry\n"); 1177 goto rddir2_exit; 1178 } 1179 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n", 1180 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start); 1181 max_len = tcon->ses->server->ops->calc_smb_size( 1182 cifsFile->srch_inf.ntwrk_buf_start); 1183 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len; 1184 1185 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL); 1186 if (tmp_buf == NULL) { 1187 rc = -ENOMEM; 1188 goto rddir2_exit; 1189 } 1190 1191 for (i = 0; i < num_to_fill; i++) { 1192 if (current_entry == NULL) { 1193 /* evaluate whether this case is an error */ 1194 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n", 1195 num_to_fill, i); 1196 break; 1197 } 1198 /* 1199 * if buggy server returns . and .. late do we want to 1200 * check for that here? 1201 */ 1202 *tmp_buf = 0; 1203 rc = cifs_filldir(current_entry, file, ctx, 1204 tmp_buf, max_len, cfid); 1205 if (rc) { 1206 if (rc > 0) 1207 rc = 0; 1208 break; 1209 } 1210 1211 ctx->pos++; 1212 if (cfid) { 1213 mutex_lock(&cfid->dirents.de_mutex); 1214 update_cached_dirents_count(&cfid->dirents, ctx); 1215 mutex_unlock(&cfid->dirents.de_mutex); 1216 } 1217 1218 if (ctx->pos == 1219 cifsFile->srch_inf.index_of_last_entry) { 1220 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n", 1221 ctx->pos, tmp_buf); 1222 cifs_save_resume_key(current_entry, cifsFile); 1223 break; 1224 } 1225 current_entry = 1226 nxt_dir_entry(current_entry, end_of_smb, 1227 cifsFile->srch_inf.info_level); 1228 } 1229 kfree(tmp_buf); 1230 1231 rddir2_exit: 1232 if (cfid) 1233 close_cached_dir(cfid); 1234 free_dentry_path(page); 1235 free_xid(xid); 1236 return rc; 1237 } 1238