// SPDX-License-Identifier: LGPL-2.1 /* * * Directory search handling * * Copyright (C) International Business Machines Corp., 2004, 2008 * Copyright (C) Red Hat, Inc., 2011 * Author(s): Steve French (sfrench@us.ibm.com) * */ #include #include #include #include #include "cifspdu.h" #include "cifsglob.h" #include "cifsproto.h" #include "cifs_unicode.h" #include "cifs_debug.h" #include "cifs_fs_sb.h" #include "cifsfs.h" #include "smb2proto.h" #include "fs_context.h" #include "cached_dir.h" /* * To be safe - for UCS to UTF-8 with strings loaded with the rare long * characters alloc more to account for such multibyte target UTF-8 * characters. */ #define UNICODE_NAME_MAX ((4 * NAME_MAX) + 2) #ifdef CONFIG_CIFS_DEBUG2 static void dump_cifs_file_struct(struct file *file, char *label) { struct cifsFileInfo *cf; if (file) { cf = file->private_data; if (cf == NULL) { cifs_dbg(FYI, "empty cifs private file data\n"); return; } if (cf->invalidHandle) cifs_dbg(FYI, "Invalid handle\n"); if (cf->srch_inf.endOfSearch) cifs_dbg(FYI, "end of search\n"); if (cf->srch_inf.emptyDir) cifs_dbg(FYI, "empty dir\n"); } } #else static inline void dump_cifs_file_struct(struct file *file, char *label) { } #endif /* DEBUG2 */ /* * Attempt to preload the dcache with the results from the FIND_FIRST/NEXT * * Find the dentry that matches "name". If there isn't one, create one. If it's * a negative dentry or the uniqueid or filetype(mode) changed, * then drop it and recreate it. */ static void cifs_prime_dcache(struct dentry *parent, struct qstr *name, struct cifs_fattr *fattr) { struct dentry *dentry, *alias; struct inode *inode; struct super_block *sb = parent->d_sb; struct cifs_sb_info *cifs_sb = CIFS_SB(sb); DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); cifs_dbg(FYI, "%s: for %s\n", __func__, name->name); dentry = d_hash_and_lookup(parent, name); if (!dentry) { /* * If we know that the inode will need to be revalidated * immediately, then don't create a new dentry for it. * We'll end up doing an on the wire call either way and * this spares us an invalidation. */ if (fattr->cf_flags & CIFS_FATTR_NEED_REVAL) return; retry: dentry = d_alloc_parallel(parent, name, &wq); } if (IS_ERR(dentry)) return; if (!d_in_lookup(dentry)) { inode = d_inode(dentry); if (inode) { if (d_mountpoint(dentry)) { dput(dentry); return; } /* * If we're generating inode numbers, then we don't * want to clobber the existing one with the one that * the readdir code created. */ if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) fattr->cf_uniqueid = CIFS_I(inode)->uniqueid; /* update inode in place * if both i_ino and i_mode didn't change */ if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid && cifs_fattr_to_inode(inode, fattr) == 0) { dput(dentry); return; } } d_invalidate(dentry); dput(dentry); goto retry; } else { inode = cifs_iget(sb, fattr); if (!inode) inode = ERR_PTR(-ENOMEM); alias = d_splice_alias(inode, dentry); d_lookup_done(dentry); if (alias && !IS_ERR(alias)) dput(alias); } dput(dentry); } static bool reparse_file_needs_reval(const struct cifs_fattr *fattr) { if (!(fattr->cf_cifsattrs & ATTR_REPARSE)) return false; /* * The DFS tags should be only intepreted by server side as per * MS-FSCC 2.1.2.1, but let's include them anyway. * * Besides, if cf_cifstag is unset (0), then we still need it to be * revalidated to know exactly what reparse point it is. */ switch (fattr->cf_cifstag) { case IO_REPARSE_TAG_DFS: case IO_REPARSE_TAG_DFSR: case IO_REPARSE_TAG_SYMLINK: case IO_REPARSE_TAG_NFS: case 0: return true; } return false; } static void cifs_fill_common_info(struct cifs_fattr *fattr, struct cifs_sb_info *cifs_sb) { fattr->cf_uid = cifs_sb->ctx->linux_uid; fattr->cf_gid = cifs_sb->ctx->linux_gid; /* * The IO_REPARSE_TAG_LX_ tags originally were used by WSL but they * are preferred by the Linux client in some cases since, unlike * the NFS reparse tag (or EAs), they don't require an extra query * to determine which type of special file they represent. * TODO: go through all documented reparse tags to see if we can * reasonably map some of them to directories vs. files vs. symlinks */ if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { fattr->cf_mode = S_IFDIR | cifs_sb->ctx->dir_mode; fattr->cf_dtype = DT_DIR; } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_SYMLINK) { fattr->cf_mode |= S_IFLNK | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_LNK; } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_FIFO) { fattr->cf_mode |= S_IFIFO | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_FIFO; } else if (fattr->cf_cifstag == IO_REPARSE_TAG_AF_UNIX) { fattr->cf_mode |= S_IFSOCK | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_SOCK; } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_CHR) { fattr->cf_mode |= S_IFCHR | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_CHR; } else if (fattr->cf_cifstag == IO_REPARSE_TAG_LX_BLK) { fattr->cf_mode |= S_IFBLK | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_BLK; } else { /* TODO: should we mark some other reparse points (like DFSR) as directories? */ fattr->cf_mode = S_IFREG | cifs_sb->ctx->file_mode; fattr->cf_dtype = DT_REG; } /* * We need to revalidate it further to make a decision about whether it * is a symbolic link, DFS referral or a reparse point with a direct * access like junctions, deduplicated files, NFS symlinks. */ if (reparse_file_needs_reval(fattr)) fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; /* non-unix readdir doesn't provide nlink */ fattr->cf_flags |= CIFS_FATTR_UNKNOWN_NLINK; if (fattr->cf_cifsattrs & ATTR_READONLY) fattr->cf_mode &= ~S_IWUGO; /* * We of course don't get ACL info in FIND_FIRST/NEXT results, so * mark it for revalidation so that "ls -l" will look right. It might * be super-slow, but if we don't do this then the ownership of files * may look wrong since the inodes may not have timed out by the time * "ls" does a stat() call on them. */ if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) || (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MODE_FROM_SID)) fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL && fattr->cf_cifsattrs & ATTR_SYSTEM) { if (fattr->cf_eof == 0) { fattr->cf_mode &= ~S_IFMT; fattr->cf_mode |= S_IFIFO; fattr->cf_dtype = DT_FIFO; } else { /* * trying to get the type and mode via SFU can be slow, * so just call those regular files for now, and mark * for reval */ fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; } } } /* Fill a cifs_fattr struct with info from SMB_FIND_FILE_POSIX_INFO. */ static void cifs_posix_to_fattr(struct cifs_fattr *fattr, struct smb2_posix_info *info, struct cifs_sb_info *cifs_sb) { struct smb2_posix_info_parsed parsed; posix_info_parse(info, NULL, &parsed); memset(fattr, 0, sizeof(*fattr)); fattr->cf_uniqueid = le64_to_cpu(info->Inode); fattr->cf_bytes = le64_to_cpu(info->AllocationSize); fattr->cf_eof = le64_to_cpu(info->EndOfFile); fattr->cf_atime = cifs_NTtimeToUnix(info->LastAccessTime); fattr->cf_mtime = cifs_NTtimeToUnix(info->LastWriteTime); fattr->cf_ctime = cifs_NTtimeToUnix(info->CreationTime); fattr->cf_nlink = le32_to_cpu(info->HardLinks); fattr->cf_cifsattrs = le32_to_cpu(info->DosAttributes); /* * Since we set the inode type below we need to mask off * to avoid strange results if bits set above. * XXX: why not make server&client use the type bits? */ fattr->cf_mode = le32_to_cpu(info->Mode) & ~S_IFMT; cifs_dbg(FYI, "posix fattr: dev %d, reparse %d, mode %o\n", le32_to_cpu(info->DeviceId), le32_to_cpu(info->ReparseTag), le32_to_cpu(info->Mode)); if (fattr->cf_cifsattrs & ATTR_DIRECTORY) { fattr->cf_mode |= S_IFDIR; fattr->cf_dtype = DT_DIR; } else { /* * mark anything that is not a dir as regular * file. special files should have the REPARSE * attribute and will be marked as needing revaluation */ fattr->cf_mode |= S_IFREG; fattr->cf_dtype = DT_REG; } if (reparse_file_needs_reval(fattr)) fattr->cf_flags |= CIFS_FATTR_NEED_REVAL; sid_to_id(cifs_sb, &parsed.owner, fattr, SIDOWNER); sid_to_id(cifs_sb, &parsed.group, fattr, SIDGROUP); } static void __dir_info_to_fattr(struct cifs_fattr *fattr, const void *info) { const FILE_DIRECTORY_INFO *fi = info; memset(fattr, 0, sizeof(*fattr)); fattr->cf_cifsattrs = le32_to_cpu(fi->ExtFileAttributes); fattr->cf_eof = le64_to_cpu(fi->EndOfFile); fattr->cf_bytes = le64_to_cpu(fi->AllocationSize); fattr->cf_createtime = le64_to_cpu(fi->CreationTime); fattr->cf_atime = cifs_NTtimeToUnix(fi->LastAccessTime); fattr->cf_ctime = cifs_NTtimeToUnix(fi->ChangeTime); fattr->cf_mtime = cifs_NTtimeToUnix(fi->LastWriteTime); } void cifs_dir_info_to_fattr(struct cifs_fattr *fattr, FILE_DIRECTORY_INFO *info, struct cifs_sb_info *cifs_sb) { __dir_info_to_fattr(fattr, info); cifs_fill_common_info(fattr, cifs_sb); } static void cifs_fulldir_info_to_fattr(struct cifs_fattr *fattr, const void *info, struct cifs_sb_info *cifs_sb) { const FILE_FULL_DIRECTORY_INFO *di = info; __dir_info_to_fattr(fattr, info); /* See MS-FSCC 2.4.14, 2.4.19 */ if (fattr->cf_cifsattrs & ATTR_REPARSE) fattr->cf_cifstag = le32_to_cpu(di->EaSize); cifs_fill_common_info(fattr, cifs_sb); } static void cifs_std_info_to_fattr(struct cifs_fattr *fattr, FIND_FILE_STANDARD_INFO *info, struct cifs_sb_info *cifs_sb) { int offset = cifs_sb_master_tcon(cifs_sb)->ses->server->timeAdj; memset(fattr, 0, sizeof(*fattr)); fattr->cf_atime = cnvrtDosUnixTm(info->LastAccessDate, info->LastAccessTime, offset); fattr->cf_ctime = cnvrtDosUnixTm(info->LastWriteDate, info->LastWriteTime, offset); fattr->cf_mtime = cnvrtDosUnixTm(info->LastWriteDate, info->LastWriteTime, offset); fattr->cf_cifsattrs = le16_to_cpu(info->Attributes); fattr->cf_bytes = le32_to_cpu(info->AllocationSize); fattr->cf_eof = le32_to_cpu(info->DataSize); cifs_fill_common_info(fattr, cifs_sb); } /* BB eventually need to add the following helper function to resolve NT_STATUS_STOPPED_ON_SYMLINK return code when we try to do FindFirst on (NTFS) directory symlinks */ /* int get_symlink_reparse_path(char *full_path, struct cifs_sb_info *cifs_sb, unsigned int xid) { __u16 fid; int len; int oplock = 0; int rc; struct cifs_tcon *ptcon = cifs_sb_tcon(cifs_sb); char *tmpbuffer; rc = CIFSSMBOpen(xid, ptcon, full_path, FILE_OPEN, GENERIC_READ, OPEN_REPARSE_POINT, &fid, &oplock, NULL, cifs_sb->local_nls, cifs_remap(cifs_sb); if (!rc) { tmpbuffer = kmalloc(maxpath); rc = CIFSSMBQueryReparseLinkInfo(xid, ptcon, full_path, tmpbuffer, maxpath -1, fid, cifs_sb->local_nls); if (CIFSSMBClose(xid, ptcon, fid)) { cifs_dbg(FYI, "Error closing temporary reparsepoint open\n"); } } } */ static int _initiate_cifs_search(const unsigned int xid, struct file *file, const char *full_path) { __u16 search_flags; int rc = 0; struct cifsFileInfo *cifsFile; struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); struct tcon_link *tlink = NULL; struct cifs_tcon *tcon; struct TCP_Server_Info *server; if (file->private_data == NULL) { tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) return PTR_ERR(tlink); cifsFile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL); if (cifsFile == NULL) { rc = -ENOMEM; goto error_exit; } spin_lock_init(&cifsFile->file_info_lock); file->private_data = cifsFile; cifsFile->tlink = cifs_get_tlink(tlink); tcon = tlink_tcon(tlink); } else { cifsFile = file->private_data; tcon = tlink_tcon(cifsFile->tlink); } server = tcon->ses->server; if (!server->ops->query_dir_first) { rc = -ENOSYS; goto error_exit; } cifsFile->invalidHandle = true; cifsFile->srch_inf.endOfSearch = false; cifs_dbg(FYI, "Full path: %s start at: %lld\n", full_path, file->f_pos); ffirst_retry: /* test for Unix extensions */ /* but now check for them on the share/mount not on the SMB session */ /* if (cap_unix(tcon->ses) { */ if (tcon->unix_ext) cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX; else if (tcon->posix_extensions) cifsFile->srch_inf.info_level = SMB_FIND_FILE_POSIX_INFO; else if ((tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find) == 0) { cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD; } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) { cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO; } else /* not srvinos - BB fixme add check for backlevel? */ { cifsFile->srch_inf.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO; } search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; if (backup_cred(cifs_sb)) search_flags |= CIFS_SEARCH_BACKUP_SEARCH; rc = server->ops->query_dir_first(xid, tcon, full_path, cifs_sb, &cifsFile->fid, search_flags, &cifsFile->srch_inf); if (rc == 0) cifsFile->invalidHandle = false; /* BB add following call to handle readdir on new NTFS symlink errors else if STATUS_STOPPED_ON_SYMLINK call get_symlink_reparse_path and retry with new path */ else if ((rc == -EOPNOTSUPP) && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM; goto ffirst_retry; } error_exit: cifs_put_tlink(tlink); return rc; } static int initiate_cifs_search(const unsigned int xid, struct file *file, const char *full_path) { int rc, retry_count = 0; do { rc = _initiate_cifs_search(xid, file, full_path); /* * If we don't have enough credits to start reading the * directory just try again after short wait. */ if (rc != -EDEADLK) break; usleep_range(512, 2048); } while (retry_count++ < 5); return rc; } /* return length of unicode string in bytes */ static int cifs_unicode_bytelen(const char *str) { int len; const __le16 *ustr = (const __le16 *)str; for (len = 0; len <= PATH_MAX; len++) { if (ustr[len] == 0) return len << 1; } cifs_dbg(FYI, "Unicode string longer than PATH_MAX found\n"); return len << 1; } static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level) { char *new_entry; FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry; if (level == SMB_FIND_FILE_INFO_STANDARD) { FIND_FILE_STANDARD_INFO *pfData; pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo; new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 + pfData->FileNameLength; } else { u32 next_offset = le32_to_cpu(pDirInfo->NextEntryOffset); if (old_entry + next_offset < old_entry) { cifs_dbg(VFS, "Invalid offset %u\n", next_offset); return NULL; } new_entry = old_entry + next_offset; } cifs_dbg(FYI, "new entry %p old entry %p\n", new_entry, old_entry); /* validate that new_entry is not past end of SMB */ if (new_entry >= end_of_smb) { cifs_dbg(VFS, "search entry %p began after end of SMB %p old entry %p\n", new_entry, end_of_smb, old_entry); return NULL; } else if (((level == SMB_FIND_FILE_INFO_STANDARD) && (new_entry + sizeof(FIND_FILE_STANDARD_INFO) + 1 > end_of_smb)) || ((level != SMB_FIND_FILE_INFO_STANDARD) && (new_entry + sizeof(FILE_DIRECTORY_INFO) + 1 > end_of_smb))) { cifs_dbg(VFS, "search entry %p extends after end of SMB %p\n", new_entry, end_of_smb); return NULL; } else return new_entry; } struct cifs_dirent { const char *name; size_t namelen; u32 resume_key; u64 ino; }; static void cifs_fill_dirent_posix(struct cifs_dirent *de, const struct smb2_posix_info *info) { struct smb2_posix_info_parsed parsed; /* payload should have already been checked at this point */ if (posix_info_parse(info, NULL, &parsed) < 0) { cifs_dbg(VFS, "Invalid POSIX info payload\n"); return; } de->name = parsed.name; de->namelen = parsed.name_len; de->resume_key = info->Ignored; de->ino = le64_to_cpu(info->Inode); } static void cifs_fill_dirent_unix(struct cifs_dirent *de, const FILE_UNIX_INFO *info, bool is_unicode) { de->name = &info->FileName[0]; if (is_unicode) de->namelen = cifs_unicode_bytelen(de->name); else de->namelen = strnlen(de->name, PATH_MAX); de->resume_key = info->ResumeKey; de->ino = le64_to_cpu(info->basic.UniqueId); } static void cifs_fill_dirent_dir(struct cifs_dirent *de, const FILE_DIRECTORY_INFO *info) { de->name = &info->FileName[0]; de->namelen = le32_to_cpu(info->FileNameLength); de->resume_key = info->FileIndex; } static void cifs_fill_dirent_full(struct cifs_dirent *de, const FILE_FULL_DIRECTORY_INFO *info) { de->name = &info->FileName[0]; de->namelen = le32_to_cpu(info->FileNameLength); de->resume_key = info->FileIndex; } static void cifs_fill_dirent_search(struct cifs_dirent *de, const SEARCH_ID_FULL_DIR_INFO *info) { de->name = &info->FileName[0]; de->namelen = le32_to_cpu(info->FileNameLength); de->resume_key = info->FileIndex; de->ino = le64_to_cpu(info->UniqueId); } static void cifs_fill_dirent_both(struct cifs_dirent *de, const FILE_BOTH_DIRECTORY_INFO *info) { de->name = &info->FileName[0]; de->namelen = le32_to_cpu(info->FileNameLength); de->resume_key = info->FileIndex; } static void cifs_fill_dirent_std(struct cifs_dirent *de, const FIND_FILE_STANDARD_INFO *info) { de->name = &info->FileName[0]; /* one byte length, no endianess conversion */ de->namelen = info->FileNameLength; de->resume_key = info->ResumeKey; } static int cifs_fill_dirent(struct cifs_dirent *de, const void *info, u16 level, bool is_unicode) { memset(de, 0, sizeof(*de)); switch (level) { case SMB_FIND_FILE_POSIX_INFO: cifs_fill_dirent_posix(de, info); break; case SMB_FIND_FILE_UNIX: cifs_fill_dirent_unix(de, info, is_unicode); break; case SMB_FIND_FILE_DIRECTORY_INFO: cifs_fill_dirent_dir(de, info); break; case SMB_FIND_FILE_FULL_DIRECTORY_INFO: cifs_fill_dirent_full(de, info); break; case SMB_FIND_FILE_ID_FULL_DIR_INFO: cifs_fill_dirent_search(de, info); break; case SMB_FIND_FILE_BOTH_DIRECTORY_INFO: cifs_fill_dirent_both(de, info); break; case SMB_FIND_FILE_INFO_STANDARD: cifs_fill_dirent_std(de, info); break; default: cifs_dbg(FYI, "Unknown findfirst level %d\n", level); return -EINVAL; } return 0; } #define UNICODE_DOT cpu_to_le16(0x2e) /* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */ static int cifs_entry_is_dot(struct cifs_dirent *de, bool is_unicode) { int rc = 0; if (!de->name) return 0; if (is_unicode) { __le16 *ufilename = (__le16 *)de->name; if (de->namelen == 2) { /* check for . */ if (ufilename[0] == UNICODE_DOT) rc = 1; } else if (de->namelen == 4) { /* check for .. */ if (ufilename[0] == UNICODE_DOT && ufilename[1] == UNICODE_DOT) rc = 2; } } else /* ASCII */ { if (de->namelen == 1) { if (de->name[0] == '.') rc = 1; } else if (de->namelen == 2) { if (de->name[0] == '.' && de->name[1] == '.') rc = 2; } } return rc; } /* Check if directory that we are searching has changed so we can decide whether we can use the cached search results from the previous search */ static int is_dir_changed(struct file *file) { struct inode *inode = file_inode(file); struct cifsInodeInfo *cifsInfo = CIFS_I(inode); if (cifsInfo->time == 0) return 1; /* directory was changed, perhaps due to unlink */ else return 0; } static int cifs_save_resume_key(const char *current_entry, struct cifsFileInfo *file_info) { struct cifs_dirent de; int rc; rc = cifs_fill_dirent(&de, current_entry, file_info->srch_inf.info_level, file_info->srch_inf.unicode); if (!rc) { file_info->srch_inf.presume_name = de.name; file_info->srch_inf.resume_name_len = de.namelen; file_info->srch_inf.resume_key = de.resume_key; } return rc; } /* * Find the corresponding entry in the search. Note that the SMB server returns * search entries for . and .. which complicates logic here if we choose to * parse for them and we do not assume that they are located in the findfirst * return buffer. We start counting in the buffer with entry 2 and increment for * every entry (do not increment for . or .. entry). */ static int find_cifs_entry(const unsigned int xid, struct cifs_tcon *tcon, loff_t pos, struct file *file, const char *full_path, char **current_entry, int *num_to_ret) { __u16 search_flags; int rc = 0; int pos_in_buf = 0; loff_t first_entry_in_buffer; loff_t index_to_find = pos; struct cifsFileInfo *cfile = file->private_data; struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); struct TCP_Server_Info *server = tcon->ses->server; /* check if index in the buffer */ if (!server->ops->query_dir_first || !server->ops->query_dir_next) return -ENOSYS; if ((cfile == NULL) || (current_entry == NULL) || (num_to_ret == NULL)) return -ENOENT; *current_entry = NULL; first_entry_in_buffer = cfile->srch_inf.index_of_last_entry - cfile->srch_inf.entries_in_buffer; /* * If first entry in buf is zero then is first buffer * in search response data which means it is likely . and .. * will be in this buffer, although some servers do not return * . and .. for the root of a drive and for those we need * to start two entries earlier. */ dump_cifs_file_struct(file, "In fce "); if (((index_to_find < cfile->srch_inf.index_of_last_entry) && is_dir_changed(file)) || (index_to_find < first_entry_in_buffer)) { /* close and restart search */ cifs_dbg(FYI, "search backing up - close and restart search\n"); spin_lock(&cfile->file_info_lock); if (server->ops->dir_needs_close(cfile)) { cfile->invalidHandle = true; spin_unlock(&cfile->file_info_lock); if (server->ops->close_dir) server->ops->close_dir(xid, tcon, &cfile->fid); } else spin_unlock(&cfile->file_info_lock); if (cfile->srch_inf.ntwrk_buf_start) { cifs_dbg(FYI, "freeing SMB ff cache buf on search rewind\n"); if (cfile->srch_inf.smallBuf) cifs_small_buf_release(cfile->srch_inf. ntwrk_buf_start); else cifs_buf_release(cfile->srch_inf. ntwrk_buf_start); cfile->srch_inf.ntwrk_buf_start = NULL; } rc = initiate_cifs_search(xid, file, full_path); if (rc) { cifs_dbg(FYI, "error %d reinitiating a search on rewind\n", rc); return rc; } /* FindFirst/Next set last_entry to NULL on malformed reply */ if (cfile->srch_inf.last_entry) cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); } search_flags = CIFS_SEARCH_CLOSE_AT_END | CIFS_SEARCH_RETURN_RESUME; if (backup_cred(cifs_sb)) search_flags |= CIFS_SEARCH_BACKUP_SEARCH; while ((index_to_find >= cfile->srch_inf.index_of_last_entry) && (rc == 0) && !cfile->srch_inf.endOfSearch) { cifs_dbg(FYI, "calling findnext2\n"); rc = server->ops->query_dir_next(xid, tcon, &cfile->fid, search_flags, &cfile->srch_inf); /* FindFirst/Next set last_entry to NULL on malformed reply */ if (cfile->srch_inf.last_entry) cifs_save_resume_key(cfile->srch_inf.last_entry, cfile); if (rc) return -ENOENT; } if (index_to_find < cfile->srch_inf.index_of_last_entry) { /* we found the buffer that contains the entry */ /* scan and find it */ int i; char *cur_ent; char *end_of_smb; if (cfile->srch_inf.ntwrk_buf_start == NULL) { cifs_dbg(VFS, "ntwrk_buf_start is NULL during readdir\n"); return -EIO; } end_of_smb = cfile->srch_inf.ntwrk_buf_start + server->ops->calc_smb_size( cfile->srch_inf.ntwrk_buf_start); cur_ent = cfile->srch_inf.srch_entries_start; first_entry_in_buffer = cfile->srch_inf.index_of_last_entry - cfile->srch_inf.entries_in_buffer; pos_in_buf = index_to_find - first_entry_in_buffer; cifs_dbg(FYI, "found entry - pos_in_buf %d\n", pos_in_buf); for (i = 0; (i < (pos_in_buf)) && (cur_ent != NULL); i++) { /* go entry by entry figuring out which is first */ cur_ent = nxt_dir_entry(cur_ent, end_of_smb, cfile->srch_inf.info_level); } if ((cur_ent == NULL) && (i < pos_in_buf)) { /* BB fixme - check if we should flag this error */ cifs_dbg(VFS, "reached end of buf searching for pos in buf %d index to find %lld rc %d\n", pos_in_buf, index_to_find, rc); } rc = 0; *current_entry = cur_ent; } else { cifs_dbg(FYI, "index not in buffer - could not findnext into it\n"); return 0; } if (pos_in_buf >= cfile->srch_inf.entries_in_buffer) { cifs_dbg(FYI, "can not return entries pos_in_buf beyond last\n"); *num_to_ret = 0; } else *num_to_ret = cfile->srch_inf.entries_in_buffer - pos_in_buf; return rc; } static bool emit_cached_dirents(struct cached_dirents *cde, struct dir_context *ctx) { struct cached_dirent *dirent; bool rc; list_for_each_entry(dirent, &cde->entries, entry) { /* * Skip all early entries prior to the current lseek() * position. */ if (ctx->pos > dirent->pos) continue; /* * We recorded the current ->pos value for the dirent * when we stored it in the cache. * However, this sequence of ->pos values may have holes * in it, for example dot-dirs returned from the server * are suppressed. * Handle this bu forcing ctx->pos to be the same as the * ->pos of the current dirent we emit from the cache. * This means that when we emit these entries from the cache * we now emit them with the same ->pos value as in the * initial scan. */ ctx->pos = dirent->pos; rc = dir_emit(ctx, dirent->name, dirent->namelen, dirent->fattr.cf_uniqueid, dirent->fattr.cf_dtype); if (!rc) return rc; ctx->pos++; } return true; } static void update_cached_dirents_count(struct cached_dirents *cde, struct dir_context *ctx) { if (cde->ctx != ctx) return; if (cde->is_valid || cde->is_failed) return; cde->pos++; } static void finished_cached_dirents_count(struct cached_dirents *cde, struct dir_context *ctx) { if (cde->ctx != ctx) return; if (cde->is_valid || cde->is_failed) return; if (ctx->pos != cde->pos) return; cde->is_valid = 1; } static void add_cached_dirent(struct cached_dirents *cde, struct dir_context *ctx, const char *name, int namelen, struct cifs_fattr *fattr) { struct cached_dirent *de; if (cde->ctx != ctx) return; if (cde->is_valid || cde->is_failed) return; if (ctx->pos != cde->pos) { cde->is_failed = 1; return; } de = kzalloc(sizeof(*de), GFP_ATOMIC); if (de == NULL) { cde->is_failed = 1; return; } de->namelen = namelen; de->name = kstrndup(name, namelen, GFP_ATOMIC); if (de->name == NULL) { kfree(de); cde->is_failed = 1; return; } de->pos = ctx->pos; memcpy(&de->fattr, fattr, sizeof(struct cifs_fattr)); list_add_tail(&de->entry, &cde->entries); } static bool cifs_dir_emit(struct dir_context *ctx, const char *name, int namelen, struct cifs_fattr *fattr, struct cached_fid *cfid) { bool rc; ino_t ino = cifs_uniqueid_to_ino_t(fattr->cf_uniqueid); rc = dir_emit(ctx, name, namelen, ino, fattr->cf_dtype); if (!rc) return rc; if (cfid) { mutex_lock(&cfid->dirents.de_mutex); add_cached_dirent(&cfid->dirents, ctx, name, namelen, fattr); mutex_unlock(&cfid->dirents.de_mutex); } return rc; } static int cifs_filldir(char *find_entry, struct file *file, struct dir_context *ctx, char *scratch_buf, unsigned int max_len, struct cached_fid *cfid) { struct cifsFileInfo *file_info = file->private_data; struct super_block *sb = file_inode(file)->i_sb; struct cifs_sb_info *cifs_sb = CIFS_SB(sb); struct cifs_dirent de = { NULL, }; struct cifs_fattr fattr; struct qstr name; int rc = 0; rc = cifs_fill_dirent(&de, find_entry, file_info->srch_inf.info_level, file_info->srch_inf.unicode); if (rc) return rc; if (de.namelen > max_len) { cifs_dbg(VFS, "bad search response length %zd past smb end\n", de.namelen); return -EINVAL; } /* skip . and .. since we added them first */ if (cifs_entry_is_dot(&de, file_info->srch_inf.unicode)) return 0; if (file_info->srch_inf.unicode) { struct nls_table *nlt = cifs_sb->local_nls; int map_type; map_type = cifs_remap(cifs_sb); name.name = scratch_buf; name.len = cifs_from_utf16((char *)name.name, (__le16 *)de.name, UNICODE_NAME_MAX, min_t(size_t, de.namelen, (size_t)max_len), nlt, map_type); name.len -= nls_nullsize(nlt); } else { name.name = de.name; name.len = de.namelen; } switch (file_info->srch_inf.info_level) { case SMB_FIND_FILE_POSIX_INFO: cifs_posix_to_fattr(&fattr, (struct smb2_posix_info *)find_entry, cifs_sb); break; case SMB_FIND_FILE_UNIX: cifs_unix_basic_to_fattr(&fattr, &((FILE_UNIX_INFO *)find_entry)->basic, cifs_sb); if (S_ISLNK(fattr.cf_mode)) fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; break; case SMB_FIND_FILE_INFO_STANDARD: cifs_std_info_to_fattr(&fattr, (FIND_FILE_STANDARD_INFO *)find_entry, cifs_sb); break; case SMB_FIND_FILE_FULL_DIRECTORY_INFO: case SMB_FIND_FILE_ID_FULL_DIR_INFO: cifs_fulldir_info_to_fattr(&fattr, find_entry, cifs_sb); break; default: cifs_dir_info_to_fattr(&fattr, (FILE_DIRECTORY_INFO *)find_entry, cifs_sb); break; } if (de.ino && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) { fattr.cf_uniqueid = de.ino; } else { fattr.cf_uniqueid = iunique(sb, ROOT_I); cifs_autodisable_serverino(cifs_sb); } if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) && couldbe_mf_symlink(&fattr)) /* * trying to get the type and mode can be slow, * so just call those regular files for now, and mark * for reval */ fattr.cf_flags |= CIFS_FATTR_NEED_REVAL; cifs_prime_dcache(file_dentry(file), &name, &fattr); return !cifs_dir_emit(ctx, name.name, name.len, &fattr, cfid); } int cifs_readdir(struct file *file, struct dir_context *ctx) { int rc = 0; unsigned int xid; int i; struct tcon_link *tlink = NULL; struct cifs_tcon *tcon; struct cifsFileInfo *cifsFile; char *current_entry; int num_to_fill = 0; char *tmp_buf = NULL; char *end_of_smb; unsigned int max_len; const char *full_path; void *page = alloc_dentry_path(); struct cached_fid *cfid = NULL; struct cifs_sb_info *cifs_sb = CIFS_FILE_SB(file); xid = get_xid(); full_path = build_path_from_dentry(file_dentry(file), page); if (IS_ERR(full_path)) { rc = PTR_ERR(full_path); goto rddir2_exit; } if (file->private_data == NULL) { tlink = cifs_sb_tlink(cifs_sb); if (IS_ERR(tlink)) goto cache_not_found; tcon = tlink_tcon(tlink); } else { cifsFile = file->private_data; tcon = tlink_tcon(cifsFile->tlink); } rc = open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); cifs_put_tlink(tlink); if (rc) goto cache_not_found; mutex_lock(&cfid->dirents.de_mutex); /* * If this was reading from the start of the directory * we need to initialize scanning and storing the * directory content. */ if (ctx->pos == 0 && cfid->dirents.ctx == NULL) { cfid->dirents.ctx = ctx; cfid->dirents.pos = 2; } /* * If we already have the entire directory cached then * we can just serve the cache. */ if (cfid->dirents.is_valid) { if (!dir_emit_dots(file, ctx)) { mutex_unlock(&cfid->dirents.de_mutex); goto rddir2_exit; } emit_cached_dirents(&cfid->dirents, ctx); mutex_unlock(&cfid->dirents.de_mutex); goto rddir2_exit; } mutex_unlock(&cfid->dirents.de_mutex); /* Drop the cache while calling initiate_cifs_search and * find_cifs_entry in case there will be reconnects during * query_directory. */ close_cached_dir(cfid); cfid = NULL; cache_not_found: /* * Ensure FindFirst doesn't fail before doing filldir() for '.' and * '..'. Otherwise we won't be able to notify VFS in case of failure. */ if (file->private_data == NULL) { rc = initiate_cifs_search(xid, file, full_path); cifs_dbg(FYI, "initiate cifs search rc %d\n", rc); if (rc) goto rddir2_exit; } if (!dir_emit_dots(file, ctx)) goto rddir2_exit; /* 1) If search is active, is in current search buffer? if it before then restart search if after then keep searching till find it */ cifsFile = file->private_data; if (cifsFile->srch_inf.endOfSearch) { if (cifsFile->srch_inf.emptyDir) { cifs_dbg(FYI, "End of search, empty dir\n"); rc = 0; goto rddir2_exit; } } /* else { cifsFile->invalidHandle = true; tcon->ses->server->close(xid, tcon, &cifsFile->fid); } */ tcon = tlink_tcon(cifsFile->tlink); rc = find_cifs_entry(xid, tcon, ctx->pos, file, full_path, ¤t_entry, &num_to_fill); open_cached_dir(xid, tcon, full_path, cifs_sb, false, &cfid); if (rc) { cifs_dbg(FYI, "fce error %d\n", rc); goto rddir2_exit; } else if (current_entry != NULL) { cifs_dbg(FYI, "entry %lld found\n", ctx->pos); } else { if (cfid) { mutex_lock(&cfid->dirents.de_mutex); finished_cached_dirents_count(&cfid->dirents, ctx); mutex_unlock(&cfid->dirents.de_mutex); } cifs_dbg(FYI, "Could not find entry\n"); goto rddir2_exit; } cifs_dbg(FYI, "loop through %d times filling dir for net buf %p\n", num_to_fill, cifsFile->srch_inf.ntwrk_buf_start); max_len = tcon->ses->server->ops->calc_smb_size( cifsFile->srch_inf.ntwrk_buf_start); end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len; tmp_buf = kmalloc(UNICODE_NAME_MAX, GFP_KERNEL); if (tmp_buf == NULL) { rc = -ENOMEM; goto rddir2_exit; } for (i = 0; i < num_to_fill; i++) { if (current_entry == NULL) { /* evaluate whether this case is an error */ cifs_dbg(VFS, "past SMB end, num to fill %d i %d\n", num_to_fill, i); break; } /* * if buggy server returns . and .. late do we want to * check for that here? */ *tmp_buf = 0; rc = cifs_filldir(current_entry, file, ctx, tmp_buf, max_len, cfid); if (rc) { if (rc > 0) rc = 0; break; } ctx->pos++; if (cfid) { mutex_lock(&cfid->dirents.de_mutex); update_cached_dirents_count(&cfid->dirents, ctx); mutex_unlock(&cfid->dirents.de_mutex); } if (ctx->pos == cifsFile->srch_inf.index_of_last_entry) { cifs_dbg(FYI, "last entry in buf at pos %lld %s\n", ctx->pos, tmp_buf); cifs_save_resume_key(current_entry, cifsFile); break; } current_entry = nxt_dir_entry(current_entry, end_of_smb, cifsFile->srch_inf.info_level); } kfree(tmp_buf); rddir2_exit: if (cfid) close_cached_dir(cfid); free_dentry_path(page); free_xid(xid); return rc; }