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1// SPDX-License-Identifier: LGPL-2.12/*3 *4 * Directory search handling5 *6 * Copyright (C) International Business Machines Corp., 2004, 20087 * Copyright (C) Red Hat, Inc., 20118 * 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#include "reparse.h"26 27/*28 * To be safe - for UCS to UTF-8 with strings loaded with the rare long29 * characters alloc more to account for such multibyte target UTF-830 * characters.31 */32#define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2)33 34#ifdef CONFIG_CIFS_DEBUG235static void dump_cifs_file_struct(struct file *file, char *label)36{37 struct cifsFileInfo *cf;38 39 if (file) {40 cf = file->private_data;41 if (cf == NULL) {42 cifs_dbg(FYI, "empty cifs private file data\n");43 return;44 }45 if (cf->invalidHandle)46 cifs_dbg(FYI, "Invalid handle\n");47 if (cf->srch_inf.endOfSearch)48 cifs_dbg(FYI, "end of search\n");49 if (cf->srch_inf.emptyDir)50 cifs_dbg(FYI, "empty dir\n");51 }52}53#else54static inline void dump_cifs_file_struct(struct file *file, char *label)55{56}57#endif /* DEBUG2 */58 59/*60 * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT61 *62 * Find the dentry that matches "name". If there isn't one, create one. If it's63 * a negative dentry or the uniqueid or filetype(mode) changed,64 * then drop it and recreate it.65 */66static void67cifs_prime_dcache(struct dentry *parent, struct qstr *name,68 struct cifs_fattr *fattr)69{70 struct dentry *dentry, *alias;71 struct inode *inode;72 struct super_block *sb = parent->d_sb;73 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);74 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq);75 int rc;76 77 cifs_dbg(FYI, "%s: for %s\n", __func__, name->name);78 79 dentry = d_hash_and_lookup(parent, name);80 if (!dentry) {81 /*82 * If we know that the inode will need to be revalidated83 * immediately, then don't create a new dentry for it.84 * We'll end up doing an on the wire call either way and85 * this spares us an invalidation.86 */87retry:88 if ((fattr->cf_cifsattrs & ATTR_REPARSE) ||89 (fattr->cf_flags & CIFS_FATTR_NEED_REVAL))90 return;91 92 dentry = d_alloc_parallel(parent, name, &wq);93 }94 if (IS_ERR(dentry))95 return;96 if (!d_in_lookup(dentry)) {97 inode = d_inode(dentry);98 if (inode) {99 if (d_mountpoint(dentry)) {100 dput(dentry);101 return;102 }103 /*104 * If we're generating inode numbers, then we don't105 * want to clobber the existing one with the one that106 * the readdir code created.107 */108 if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))109 fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;110 111 /*112 * Update inode in place if both i_ino and i_mode didn't113 * change.114 */115 if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid) {116 /*117 * Query dir responses don't provide enough118 * information about reparse points other than119 * their reparse tags. Save an invalidation by120 * not clobbering some existing attributes when121 * reparse tag and ctime haven't changed.122 */123 rc = 0;124 if (fattr->cf_cifsattrs & ATTR_REPARSE) {125 if (likely(reparse_inode_match(inode, fattr))) {126 fattr->cf_mode = inode->i_mode;127 fattr->cf_rdev = inode->i_rdev;128 fattr->cf_uid = inode->i_uid;129 fattr->cf_gid = inode->i_gid;130 fattr->cf_eof = CIFS_I(inode)->netfs.remote_i_size;131 fattr->cf_symlink_target = NULL;132 } else {133 CIFS_I(inode)->time = 0;134 rc = -ESTALE;135 }136 }137 if (!rc && !cifs_fattr_to_inode(inode, fattr, true)) {138 dput(dentry);139 return;140 }141 }142 }143 d_invalidate(dentry);144 dput(dentry);145 goto retry;146 } else {147 inode = cifs_iget(sb, fattr);148 if (!inode)149 inode = ERR_PTR(-ENOMEM);150 alias = d_splice_alias(inode, dentry);151 d_lookup_done(dentry);152 if (alias && !IS_ERR(alias))153 dput(alias);154 }155 dput(dentry);156}157 158static void159cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb)160{161 struct cifs_open_info_data data = {162 .reparse = { .tag = fattr->cf_cifstag, },163 };164 165 fattr->cf_uid = cifs_sb->ctx->linux_uid;166 fattr->cf_gid = cifs_sb->ctx->linux_gid;167 168 /*169 * The IO_REPARSE_TAG_LX_ tags originally were used by WSL but they170 * are preferred by the Linux client in some cases since, unlike171 * the NFS reparse tag (or EAs), they don't require an extra query172 * to determine which type of special file they represent.173 * TODO: go through all documented reparse tags to see if we can174 * reasonably map some of them to directories vs. files vs. symlinks175 */176 if ((fattr->cf_cifsattrs & ATTR_REPARSE) &&177 cifs_reparse_point_to_fattr(cifs_sb, fattr, &data))178 goto out_reparse;179 180 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {181 fattr->cf_mode = S_IFDIR | cifs_sb->ctx->dir_mode;182 fattr->cf_dtype = DT_DIR;183 } else {184 fattr->cf_mode = S_IFREG | cifs_sb->ctx->file_mode;185 fattr->cf_dtype = DT_REG;186 }187 188out_reparse:189 /* non-unix readdir doesn't provide nlink */190 fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK;191 192 if (fattr->cf_cifsattrs & ATTR_READONLY)193 fattr->cf_mode &= ~S_IWUGO;194 195 /*196 * We of course don't get ACL info in FIND_FIRST/NEXT results, so197 * mark it for revalidation so that "ls -l" will look right. It might198 * be super-slow, but if we don't do this then the ownership of files199 * may look wrong since the inodes may not have timed out by the time200 * "ls" does a stat() call on them.201 */202 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) ||203 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID))204 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;205 206 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL &&207 fattr->cf_cifsattrs & ATTR_SYSTEM) {208 if (fattr->cf_eof == 0) {209 fattr->cf_mode &= ~S_IFMT;210 fattr->cf_mode |= S_IFIFO;211 fattr->cf_dtype = DT_FIFO;212 } else {213 /*214 * trying to get the type and mode via SFU can be slow,215 * so just call those regular files for now, and mark216 * for reval217 */218 fattr->cf_flags |= CIFS_FATTR_NEED_REVAL;219 }220 }221}222 223/* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */224static void225cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info,226 struct cifs_sb_info *cifs_sb)227{228 struct smb2_posix_info_parsed parsed;229 230 posix_info_parse(info, NULL, &parsed);231 232 memset(fattr, 0, sizeof(*fattr));233 fattr->cf_uniqueid = le64_to_cpu(info->Inode);234 fattr->cf_bytes = le64_to_cpu(info->AllocationSize);235 fattr->cf_eof = le64_to_cpu(info->EndOfFile);236 237 fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime);238 fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime);239 fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime);240 241 fattr->cf_nlink = le32_to_cpu(info->HardLinks);242 fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes);243 244 /*245 * Since we set the inode type below we need to mask off246 * to avoid strange results if bits set above.247 * XXX: why not make server&client use the type bits?248 */249 fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT;250 251 cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n",252 le32_to_cpu(info->DeviceId),253 le32_to_cpu(info->ReparseTag),254 le32_to_cpu(info->Mode));255 256 if (fattr->cf_cifsattrs & ATTR_DIRECTORY) {257 fattr->cf_mode |= S_IFDIR;258 fattr->cf_dtype = DT_DIR;259 } else {260 /*261 * mark anything that is not a dir as regular262 * file. special files should have the REPARSE263 * attribute and will be marked as needing revaluation264 */265 fattr->cf_mode |= S_IFREG;266 fattr->cf_dtype = DT_REG;267 }268 269 sid_to_id(cifs_sb, &parsed.owner, fattr, SIDOWNER);270 sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP);271}272 273static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info)274{275 const FILE_DIRECTORY_INFO *fi = info;276 277 memset(fattr, 0, sizeof(*fattr));278 fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes);279 fattr->cf_eof = le64_to_cpu(fi->EndOfFile);280 fattr->cf_bytes = le64_to_cpu(fi->AllocationSize);281 fattr->cf_createtime = le64_to_cpu(fi->CreationTime);282 fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime);283 fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime);284 fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime);285}286 287void288cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info,289 struct cifs_sb_info *cifs_sb)290{291 __dir_info_to_fattr(fattr, info);292 cifs_fill_common_info(fattr, cifs_sb);293}294 295static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr,296 const void *info,297 struct cifs_sb_info *cifs_sb)298{299 const FILE_FULL_DIRECTORY_INFO *di = info;300 301 __dir_info_to_fattr(fattr, info);302 303 /* See MS-FSCC 2.4.14, 2.4.19 */304 if (fattr->cf_cifsattrs & ATTR_REPARSE)305 fattr->cf_cifstag = le32_to_cpu(di->EaSize);306 cifs_fill_common_info(fattr, cifs_sb);307}308 309static void310cifs_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 330static int331_initiate_cifs_search(const unsigned int xid, struct file *file,332 const char *full_path)333{334 __u16 search_flags;335 int rc = 0;336 struct cifsFileInfo *cifsFile;337 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);338 struct tcon_link *tlink = NULL;339 struct cifs_tcon *tcon;340 struct TCP_Server_Info *server;341 342 if (file->private_data == NULL) {343 tlink = cifs_sb_tlink(cifs_sb);344 if (IS_ERR(tlink))345 return PTR_ERR(tlink);346 347 cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);348 if (cifsFile == NULL) {349 rc = -ENOMEM;350 goto error_exit;351 }352 spin_lock_init(&cifsFile->file_info_lock);353 file->private_data = cifsFile;354 cifsFile->tlink = cifs_get_tlink(tlink);355 tcon = tlink_tcon(tlink);356 } else {357 cifsFile = file->private_data;358 tcon = tlink_tcon(cifsFile->tlink);359 }360 361 server = tcon->ses->server;362 363 if (!server->ops->query_dir_first) {364 rc = -ENOSYS;365 goto error_exit;366 }367 368 cifsFile->invalidHandle = true;369 cifsFile->srch_inf.endOfSearch = false;370 371 cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos);372 373ffirst_retry:374 /* test for Unix extensions */375 /* but now check for them on the share/mount not on the SMB session */376 /* if (cap_unix(tcon->ses) { */377 if (tcon->unix_ext)378 cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;379 else if (tcon->posix_extensions)380 cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO;381 else if ((tcon->ses->capabilities &382 tcon->ses->server->vals->cap_nt_find) == 0) {383 cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;384 } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {385 cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;386 } else /* not srvinos - BB fixme add check for backlevel? */ {387 cifsFile->srch_inf.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO;388 }389 390 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;391 if (backup_cred(cifs_sb))392 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;393 394 rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb,395 &cifsFile->fid, search_flags,396 &cifsFile->srch_inf);397 398 if (rc == 0) {399 cifsFile->invalidHandle = false;400 } else if ((rc == -EOPNOTSUPP) &&401 (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {402 cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;403 goto ffirst_retry;404 }405error_exit:406 cifs_put_tlink(tlink);407 return rc;408}409 410static int411initiate_cifs_search(const unsigned int xid, struct file *file,412 const char *full_path)413{414 int rc, retry_count = 0;415 416 do {417 rc = _initiate_cifs_search(xid, file, full_path);418 /*419 * If we don't have enough credits to start reading the420 * directory just try again after short wait.421 */422 if (rc != -EDEADLK)423 break;424 425 usleep_range(512, 2048);426 } while (retry_count++ < 5);427 428 return rc;429}430 431/* return length of unicode string in bytes */432static int cifs_unicode_bytelen(const char *str)433{434 int len;435 const __le16 *ustr = (const __le16 *)str;436 437 for (len = 0; len <= PATH_MAX; len++) {438 if (ustr[len] == 0)439 return len << 1;440 }441 cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n");442 return len << 1;443}444 445static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)446{447 char *new_entry;448 FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;449 450 if (level == SMB_FIND_FILE_INFO_STANDARD) {451 FIND_FILE_STANDARD_INFO *pfData;452 pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;453 454 new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 +455 pfData->FileNameLength;456 } else {457 u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset);458 459 if (old_entry + next_offset < old_entry) {460 cifs_dbg(VFS, "Invalid offset %u\n", next_offset);461 return NULL;462 }463 new_entry = old_entry + next_offset;464 }465 cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry);466 /* validate that new_entry is not past end of SMB */467 if (new_entry >= end_of_smb) {468 cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n",469 new_entry, end_of_smb, old_entry);470 return NULL;471 } else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&472 (new_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 > end_of_smb))473 || ((level != SMB_FIND_FILE_INFO_STANDARD) &&474 (new_entry + sizeof(FILE_DIRECTORY_INFO) + 1 > end_of_smb))) {475 cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n",476 new_entry, end_of_smb);477 return NULL;478 } else479 return new_entry;480 481}482 483struct cifs_dirent {484 const char *name;485 size_t namelen;486 u32 resume_key;487 u64 ino;488};489 490static void cifs_fill_dirent_posix(struct cifs_dirent *de,491 const struct smb2_posix_info *info)492{493 struct smb2_posix_info_parsed parsed;494 495 /* payload should have already been checked at this point */496 if (posix_info_parse(info, NULL, &parsed) < 0) {497 cifs_dbg(VFS, "Invalid POSIX info payload\n");498 return;499 }500 501 de->name = parsed.name;502 de->namelen = parsed.name_len;503 de->resume_key = info->Ignored;504 de->ino = le64_to_cpu(info->Inode);505}506 507static void cifs_fill_dirent_unix(struct cifs_dirent *de,508 const FILE_UNIX_INFO *info, bool is_unicode)509{510 de->name = &info->FileName[0];511 if (is_unicode)512 de->namelen = cifs_unicode_bytelen(de->name);513 else514 de->namelen = strnlen(de->name, PATH_MAX);515 de->resume_key = info->ResumeKey;516 de->ino = le64_to_cpu(info->basic.UniqueId);517}518 519static void cifs_fill_dirent_dir(struct cifs_dirent *de,520 const FILE_DIRECTORY_INFO *info)521{522 de->name = &info->FileName[0];523 de->namelen = le32_to_cpu(info->FileNameLength);524 de->resume_key = info->FileIndex;525}526 527static void cifs_fill_dirent_full(struct cifs_dirent *de,528 const FILE_FULL_DIRECTORY_INFO *info)529{530 de->name = &info->FileName[0];531 de->namelen = le32_to_cpu(info->FileNameLength);532 de->resume_key = info->FileIndex;533}534 535static void cifs_fill_dirent_search(struct cifs_dirent *de,536 const SEARCH_ID_FULL_DIR_INFO *info)537{538 de->name = &info->FileName[0];539 de->namelen = le32_to_cpu(info->FileNameLength);540 de->resume_key = info->FileIndex;541 de->ino = le64_to_cpu(info->UniqueId);542}543 544static void cifs_fill_dirent_both(struct cifs_dirent *de,545 const FILE_BOTH_DIRECTORY_INFO *info)546{547 de->name = &info->FileName[0];548 de->namelen = le32_to_cpu(info->FileNameLength);549 de->resume_key = info->FileIndex;550}551 552static void cifs_fill_dirent_std(struct cifs_dirent *de,553 const FIND_FILE_STANDARD_INFO *info)554{555 de->name = &info->FileName[0];556 /* one byte length, no endianness conversion */557 de->namelen = info->FileNameLength;558 de->resume_key = info->ResumeKey;559}560 561static int cifs_fill_dirent(struct cifs_dirent *de, const void *info,562 u16 level, bool is_unicode)563{564 memset(de, 0, sizeof(*de));565 566 switch (level) {567 case SMB_FIND_FILE_POSIX_INFO:568 cifs_fill_dirent_posix(de, info);569 break;570 case SMB_FIND_FILE_UNIX:571 cifs_fill_dirent_unix(de, info, is_unicode);572 break;573 case SMB_FIND_FILE_DIRECTORY_INFO:574 cifs_fill_dirent_dir(de, info);575 break;576 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:577 cifs_fill_dirent_full(de, info);578 break;579 case SMB_FIND_FILE_ID_FULL_DIR_INFO:580 cifs_fill_dirent_search(de, info);581 break;582 case SMB_FIND_FILE_BOTH_DIRECTORY_INFO:583 cifs_fill_dirent_both(de, info);584 break;585 case SMB_FIND_FILE_INFO_STANDARD:586 cifs_fill_dirent_std(de, info);587 break;588 default:589 cifs_dbg(FYI, "Unknown findfirst level %d\n", level);590 return -EINVAL;591 }592 593 return 0;594}595 596#define UNICODE_DOT cpu_to_le16(0x2e)597 598/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */599static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode)600{601 int rc = 0;602 603 if (!de->name)604 return 0;605 606 if (is_unicode) {607 __le16 *ufilename = (__le16 *)de->name;608 if (de->namelen == 2) {609 /* check for . */610 if (ufilename[0] == UNICODE_DOT)611 rc = 1;612 } else if (de->namelen == 4) {613 /* check for .. */614 if (ufilename[0] == UNICODE_DOT &&615 ufilename[1] == UNICODE_DOT)616 rc = 2;617 }618 } else /* ASCII */ {619 if (de->namelen == 1) {620 if (de->name[0] == '.')621 rc = 1;622 } else if (de->namelen == 2) {623 if (de->name[0] == '.' && de->name[1] == '.')624 rc = 2;625 }626 }627 628 return rc;629}630 631/* Check if directory that we are searching has changed so we can decide632 whether we can use the cached search results from the previous search */633static int is_dir_changed(struct file *file)634{635 struct inode *inode = file_inode(file);636 struct cifsInodeInfo *cifs_inode_info = CIFS_I(inode);637 638 if (cifs_inode_info->time == 0)639 return 1; /* directory was changed, e.g. unlink or new file */640 else641 return 0;642 643}644 645static int cifs_save_resume_key(const char *current_entry,646 struct cifsFileInfo *file_info)647{648 struct cifs_dirent de;649 int rc;650 651 rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level,652 file_info->srch_inf.unicode);653 if (!rc) {654 file_info->srch_inf.presume_name = de.name;655 file_info->srch_inf.resume_name_len = de.namelen;656 file_info->srch_inf.resume_key = de.resume_key;657 }658 return rc;659}660 661/*662 * Find the corresponding entry in the search. Note that the SMB server returns663 * search entries for . and .. which complicates logic here if we choose to664 * parse for them and we do not assume that they are located in the findfirst665 * return buffer. We start counting in the buffer with entry 2 and increment for666 * every entry (do not increment for . or .. entry).667 */668static int669find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos,670 struct file *file, const char *full_path,671 char **current_entry, int *num_to_ret)672{673 __u16 search_flags;674 int rc = 0;675 int pos_in_buf = 0;676 loff_t first_entry_in_buffer;677 loff_t index_to_find = pos;678 struct cifsFileInfo *cfile = file->private_data;679 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);680 struct TCP_Server_Info *server = tcon->ses->server;681 /* check if index in the buffer */682 683 if (!server->ops->query_dir_first || !server->ops->query_dir_next)684 return -ENOSYS;685 686 if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL))687 return -ENOENT;688 689 *current_entry = NULL;690 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry -691 cfile->srch_inf.entries_in_buffer;692 693 /*694 * If first entry in buf is zero then is first buffer695 * in search response data which means it is likely . and ..696 * will be in this buffer, although some servers do not return697 * . and .. for the root of a drive and for those we need698 * to start two entries earlier.699 */700 701 dump_cifs_file_struct(file, "In fce ");702 if (((index_to_find < cfile->srch_inf.index_of_last_entry) &&703 is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) {704 /* close and restart search */705 cifs_dbg(FYI, "search backing up - close and restart search\n");706 spin_lock(&cfile->file_info_lock);707 if (server->ops->dir_needs_close(cfile)) {708 cfile->invalidHandle = true;709 spin_unlock(&cfile->file_info_lock);710 if (server->ops->close_dir)711 server->ops->close_dir(xid, tcon, &cfile->fid);712 } else713 spin_unlock(&cfile->file_info_lock);714 if (cfile->srch_inf.ntwrk_buf_start) {715 cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n");716 if (cfile->srch_inf.smallBuf)717 cifs_small_buf_release(cfile->srch_inf.718 ntwrk_buf_start);719 else720 cifs_buf_release(cfile->srch_inf.721 ntwrk_buf_start);722 cfile->srch_inf.ntwrk_buf_start = NULL;723 }724 rc = initiate_cifs_search(xid, file, full_path);725 if (rc) {726 cifs_dbg(FYI, "error %d reinitiating a search on rewind\n",727 rc);728 return rc;729 }730 /* FindFirst/Next set last_entry to NULL on malformed reply */731 if (cfile->srch_inf.last_entry)732 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);733 }734 735 search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME;736 if (backup_cred(cifs_sb))737 search_flags |= CIFS_SEARCH_BACKUP_SEARCH;738 739 while ((index_to_find >= cfile->srch_inf.index_of_last_entry) &&740 (rc == 0) && !cfile->srch_inf.endOfSearch) {741 cifs_dbg(FYI, "calling findnext2\n");742 rc = server->ops->query_dir_next(xid, tcon, &cfile->fid,743 search_flags,744 &cfile->srch_inf);745 /* FindFirst/Next set last_entry to NULL on malformed reply */746 if (cfile->srch_inf.last_entry)747 cifs_save_resume_key(cfile->srch_inf.last_entry, cfile);748 if (rc)749 return -ENOENT;750 }751 if (index_to_find < cfile->srch_inf.index_of_last_entry) {752 /* we found the buffer that contains the entry */753 /* scan and find it */754 int i;755 char *cur_ent;756 char *end_of_smb;757 758 if (cfile->srch_inf.ntwrk_buf_start == NULL) {759 cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n");760 return -EIO;761 }762 763 end_of_smb = cfile->srch_inf.ntwrk_buf_start +764 server->ops->calc_smb_size(765 cfile->srch_inf.ntwrk_buf_start);766 767 cur_ent = cfile->srch_inf.srch_entries_start;768 first_entry_in_buffer = cfile->srch_inf.index_of_last_entry769 - cfile->srch_inf.entries_in_buffer;770 pos_in_buf = index_to_find - first_entry_in_buffer;771 cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf);772 773 for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) {774 /* go entry by entry figuring out which is first */775 cur_ent = nxt_dir_entry(cur_ent, end_of_smb,776 cfile->srch_inf.info_level);777 }778 if ((cur_ent == NULL) && (i < pos_in_buf)) {779 /* BB fixme - check if we should flag this error */780 cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n",781 pos_in_buf, index_to_find, rc);782 }783 rc = 0;784 *current_entry = cur_ent;785 } else {786 cifs_dbg(FYI, "index not in buffer - could not findnext into it\n");787 return 0;788 }789 790 if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) {791 cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n");792 *num_to_ret = 0;793 } else794 *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf;795 796 return rc;797}798 799static bool emit_cached_dirents(struct cached_dirents *cde,800 struct dir_context *ctx)801{802 struct cached_dirent *dirent;803 bool rc;804 805 list_for_each_entry(dirent, &cde->entries, entry) {806 /*807 * Skip all early entries prior to the current lseek()808 * position.809 */810 if (ctx->pos > dirent->pos)811 continue;812 /*813 * We recorded the current ->pos value for the dirent814 * when we stored it in the cache.815 * However, this sequence of ->pos values may have holes816 * in it, for example dot-dirs returned from the server817 * are suppressed.818 * Handle this by forcing ctx->pos to be the same as the819 * ->pos of the current dirent we emit from the cache.820 * This means that when we emit these entries from the cache821 * we now emit them with the same ->pos value as in the822 * initial scan.823 */824 ctx->pos = dirent->pos;825 rc = dir_emit(ctx, dirent->name, dirent->namelen,826 dirent->fattr.cf_uniqueid,827 dirent->fattr.cf_dtype);828 if (!rc)829 return rc;830 ctx->pos++;831 }832 return true;833}834 835static void update_cached_dirents_count(struct cached_dirents *cde,836 struct dir_context *ctx)837{838 if (cde->ctx != ctx)839 return;840 if (cde->is_valid || cde->is_failed)841 return;842 843 cde->pos++;844}845 846static void finished_cached_dirents_count(struct cached_dirents *cde,847 struct dir_context *ctx)848{849 if (cde->ctx != ctx)850 return;851 if (cde->is_valid || cde->is_failed)852 return;853 if (ctx->pos != cde->pos)854 return;855 856 cde->is_valid = 1;857}858 859static void add_cached_dirent(struct cached_dirents *cde,860 struct dir_context *ctx,861 const char *name, int namelen,862 struct cifs_fattr *fattr)863{864 struct cached_dirent *de;865 866 if (cde->ctx != ctx)867 return;868 if (cde->is_valid || cde->is_failed)869 return;870 if (ctx->pos != cde->pos) {871 cde->is_failed = 1;872 return;873 }874 de = kzalloc(sizeof(*de), GFP_ATOMIC);875 if (de == NULL) {876 cde->is_failed = 1;877 return;878 }879 de->namelen = namelen;880 de->name = kstrndup(name, namelen, GFP_ATOMIC);881 if (de->name == NULL) {882 kfree(de);883 cde->is_failed = 1;884 return;885 }886 de->pos = ctx->pos;887 888 memcpy(&de->fattr, fattr, sizeof(struct cifs_fattr));889 890 list_add_tail(&de->entry, &cde->entries);891}892 893static bool cifs_dir_emit(struct dir_context *ctx,894 const char *name, int namelen,895 struct cifs_fattr *fattr,896 struct cached_fid *cfid)897{898 bool rc;899 ino_t ino = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid);900 901 rc = dir_emit(ctx, name, namelen, ino, fattr->cf_dtype);902 if (!rc)903 return rc;904 905 if (cfid) {906 mutex_lock(&cfid->dirents.de_mutex);907 add_cached_dirent(&cfid->dirents, ctx, name, namelen,908 fattr);909 mutex_unlock(&cfid->dirents.de_mutex);910 }911 912 return rc;913}914 915static int cifs_filldir(char *find_entry, struct file *file,916 struct dir_context *ctx,917 char *scratch_buf, unsigned int max_len,918 struct cached_fid *cfid)919{920 struct cifsFileInfo *file_info = file->private_data;921 struct super_block *sb = file_inode(file)->i_sb;922 struct cifs_sb_info *cifs_sb = CIFS_SB(sb);923 struct cifs_dirent de = { NULL, };924 struct cifs_fattr fattr;925 struct qstr name;926 int rc = 0;927 928 rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level,929 file_info->srch_inf.unicode);930 if (rc)931 return rc;932 933 if (de.namelen > max_len) {934 cifs_dbg(VFS, "bad search response length %zd past smb end\n",935 de.namelen);936 return -EINVAL;937 }938 939 /* skip . and .. since we added them first */940 if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode))941 return 0;942 943 if (file_info->srch_inf.unicode) {944 struct nls_table *nlt = cifs_sb->local_nls;945 int map_type;946 947 map_type = cifs_remap(cifs_sb);948 name.name = scratch_buf;949 name.len =950 cifs_from_utf16((char *)name.name, (__le16 *)de.name,951 UNICODE_NAME_MAX,952 min_t(size_t, de.namelen,953 (size_t)max_len), nlt, map_type);954 name.len -= nls_nullsize(nlt);955 } else {956 name.name = de.name;957 name.len = de.namelen;958 }959 960 switch (file_info->srch_inf.info_level) {961 case SMB_FIND_FILE_POSIX_INFO:962 cifs_posix_to_fattr(&fattr,963 (struct smb2_posix_info *)find_entry,964 cifs_sb);965 break;966 case SMB_FIND_FILE_UNIX:967 cifs_unix_basic_to_fattr(&fattr,968 &((FILE_UNIX_INFO *)find_entry)->basic,969 cifs_sb);970 if (S_ISLNK(fattr.cf_mode))971 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;972 break;973 case SMB_FIND_FILE_INFO_STANDARD:974 cifs_std_info_to_fattr(&fattr,975 (FIND_FILE_STANDARD_INFO *)find_entry,976 cifs_sb);977 break;978 case SMB_FIND_FILE_FULL_DIRECTORY_INFO:979 case SMB_FIND_FILE_ID_FULL_DIR_INFO:980 cifs_fulldir_info_to_fattr(&fattr, find_entry, cifs_sb);981 break;982 default:983 cifs_dir_info_to_fattr(&fattr,984 (FILE_DIRECTORY_INFO *)find_entry,985 cifs_sb);986 break;987 }988 989 if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {990 fattr.cf_uniqueid = de.ino;991 } else {992 fattr.cf_uniqueid = iunique(sb, ROOT_I);993 cifs_autodisable_serverino(cifs_sb);994 }995 996 if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&997 couldbe_mf_symlink(&fattr))998 /*999 * trying to get the type and mode can be slow,1000 * so just call those regular files for now, and mark1001 * for reval1002 */1003 fattr.cf_flags |= CIFS_FATTR_NEED_REVAL;1004 1005 cifs_prime_dcache(file_dentry(file), &name, &fattr);1006 1007 return !cifs_dir_emit(ctx, name.name, name.len,1008 &fattr, cfid);1009}1010 1011 1012int cifs_readdir(struct file *file, struct dir_context *ctx)1013{1014 int rc = 0;1015 unsigned int xid;1016 int i;1017 struct tcon_link *tlink = NULL;1018 struct cifs_tcon *tcon;1019 struct cifsFileInfo *cifsFile;1020 char *current_entry;1021 int num_to_fill = 0;1022 char *tmp_buf = NULL;1023 char *end_of_smb;1024 unsigned int max_len;1025 const char *full_path;1026 void *page = alloc_dentry_path();1027 struct cached_fid *cfid = NULL;1028 struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file);1029 1030 xid = get_xid();1031 1032 full_path = build_path_from_dentry(file_dentry(file), page);1033 if (IS_ERR(full_path)) {1034 rc = PTR_ERR(full_path);1035 goto rddir2_exit;1036 }1037 1038 if (file->private_data == NULL) {1039 tlink = cifs_sb_tlink(cifs_sb);1040 if (IS_ERR(tlink))1041 goto cache_not_found;1042 tcon = tlink_tcon(tlink);1043 } else {1044 cifsFile = file->private_data;1045 tcon = tlink_tcon(cifsFile->tlink);1046 }1047 1048 rc = open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid);1049 cifs_put_tlink(tlink);1050 if (rc)1051 goto cache_not_found;1052 1053 mutex_lock(&cfid->dirents.de_mutex);1054 /*1055 * If this was reading from the start of the directory1056 * we need to initialize scanning and storing the1057 * directory content.1058 */1059 if (ctx->pos == 0 && cfid->dirents.ctx == NULL) {1060 cfid->dirents.ctx = ctx;1061 cfid->dirents.pos = 2;1062 }1063 /*1064 * If we already have the entire directory cached then1065 * we can just serve the cache.1066 */1067 if (cfid->dirents.is_valid) {1068 if (!dir_emit_dots(file, ctx)) {1069 mutex_unlock(&cfid->dirents.de_mutex);1070 goto rddir2_exit;1071 }1072 emit_cached_dirents(&cfid->dirents, ctx);1073 mutex_unlock(&cfid->dirents.de_mutex);1074 goto rddir2_exit;1075 }1076 mutex_unlock(&cfid->dirents.de_mutex);1077 1078 /* Drop the cache while calling initiate_cifs_search and1079 * find_cifs_entry in case there will be reconnects during1080 * query_directory.1081 */1082 close_cached_dir(cfid);1083 cfid = NULL;1084 1085 cache_not_found:1086 /*1087 * Ensure FindFirst doesn't fail before doing filldir() for '.' and1088 * '..'. Otherwise we won't be able to notify VFS in case of failure.1089 */1090 if (file->private_data == NULL) {1091 rc = initiate_cifs_search(xid, file, full_path);1092 cifs_dbg(FYI, "initiate cifs search rc %d\n", rc);1093 if (rc)1094 goto rddir2_exit;1095 }1096 1097 if (!dir_emit_dots(file, ctx))1098 goto rddir2_exit;1099 1100 /* 1) If search is active,1101 is in current search buffer?1102 if it before then restart search1103 if after then keep searching till find it */1104 cifsFile = file->private_data;1105 if (cifsFile->srch_inf.endOfSearch) {1106 if (cifsFile->srch_inf.emptyDir) {1107 cifs_dbg(FYI, "End of search, empty dir\n");1108 rc = 0;1109 goto rddir2_exit;1110 }1111 } /* else {1112 cifsFile->invalidHandle = true;1113 tcon->ses->server->close(xid, tcon, &cifsFile->fid);1114 } */1115 1116 tcon = tlink_tcon(cifsFile->tlink);1117 rc = find_cifs_entry(xid, tcon, ctx->pos, file, full_path,1118 ¤t_entry, &num_to_fill);1119 open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid);1120 if (rc) {1121 cifs_dbg(FYI, "fce error %d\n", rc);1122 goto rddir2_exit;1123 } else if (current_entry != NULL) {1124 cifs_dbg(FYI, "entry %lld found\n", ctx->pos);1125 } else {1126 if (cfid) {1127 mutex_lock(&cfid->dirents.de_mutex);1128 finished_cached_dirents_count(&cfid->dirents, ctx);1129 mutex_unlock(&cfid->dirents.de_mutex);1130 }1131 cifs_dbg(FYI, "Could not find entry\n");1132 goto rddir2_exit;1133 }1134 cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n",1135 num_to_fill, cifsFile->srch_inf.ntwrk_buf_start);1136 max_len = tcon->ses->server->ops->calc_smb_size(1137 cifsFile->srch_inf.ntwrk_buf_start);1138 end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;1139 1140 tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL);1141 if (tmp_buf == NULL) {1142 rc = -ENOMEM;1143 goto rddir2_exit;1144 }1145 1146 for (i = 0; i < num_to_fill; i++) {1147 if (current_entry == NULL) {1148 /* evaluate whether this case is an error */1149 cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n",1150 num_to_fill, i);1151 break;1152 }1153 /*1154 * if buggy server returns . and .. late do we want to1155 * check for that here?1156 */1157 *tmp_buf = 0;1158 rc = cifs_filldir(current_entry, file, ctx,1159 tmp_buf, max_len, cfid);1160 if (rc) {1161 if (rc > 0)1162 rc = 0;1163 break;1164 }1165 1166 ctx->pos++;1167 if (cfid) {1168 mutex_lock(&cfid->dirents.de_mutex);1169 update_cached_dirents_count(&cfid->dirents, ctx);1170 mutex_unlock(&cfid->dirents.de_mutex);1171 }1172 1173 if (ctx->pos ==1174 cifsFile->srch_inf.index_of_last_entry) {1175 cifs_dbg(FYI, "last entry in buf at pos %lld %s\n",1176 ctx->pos, tmp_buf);1177 cifs_save_resume_key(current_entry, cifsFile);1178 break;1179 }1180 current_entry =1181 nxt_dir_entry(current_entry, end_of_smb,1182 cifsFile->srch_inf.info_level);1183 }1184 kfree(tmp_buf);1185 1186rddir2_exit:1187 if (cfid)1188 close_cached_dir(cfid);1189 free_dentry_path(page);1190 free_xid(xid);1191 return rc;1192}1193