diff options
Diffstat (limited to '')
-rw-r--r-- | fs/ext4/dir.c | 125 |
1 files changed, 41 insertions, 84 deletions
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index 9aa1f75409b0..3985f8c33f95 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -55,6 +55,18 @@ static int is_dx_dir(struct inode *inode) return 0; } +static bool is_fake_dir_entry(struct ext4_dir_entry_2 *de) +{ + /* Check if . or .. , or skip if namelen is 0 */ + if ((de->name_len > 0) && (de->name_len <= 2) && (de->name[0] == '.') && + (de->name[1] == '.' || de->name[1] == '\0')) + return true; + /* Check if this is a csum entry */ + if (de->file_type == EXT4_FT_DIR_CSUM) + return true; + return false; +} + /* * Return 0 if the directory entry is OK, and 1 if there is a problem * @@ -73,16 +85,20 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, const int rlen = ext4_rec_len_from_disk(de->rec_len, dir->i_sb->s_blocksize); const int next_offset = ((char *) de - buf) + rlen; + bool fake = is_fake_dir_entry(de); + bool has_csum = ext4_has_metadata_csum(dir->i_sb); - if (unlikely(rlen < EXT4_DIR_REC_LEN(1))) + if (unlikely(rlen < ext4_dir_rec_len(1, fake ? NULL : dir))) error_msg = "rec_len is smaller than minimal"; else if (unlikely(rlen % 4 != 0)) error_msg = "rec_len % 4 != 0"; - else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) + else if (unlikely(rlen < ext4_dir_rec_len(de->name_len, + fake ? NULL : dir))) error_msg = "rec_len is too small for name_len"; else if (unlikely(next_offset > size)) error_msg = "directory entry overrun"; - else if (unlikely(next_offset > size - EXT4_DIR_REC_LEN(1) && + else if (unlikely(next_offset > size - ext4_dir_rec_len(1, + has_csum ? NULL : dir) && next_offset != size)) error_msg = "directory entry too close to block end"; else if (unlikely(le32_to_cpu(de->inode) > @@ -94,15 +110,15 @@ int __ext4_check_dir_entry(const char *function, unsigned int line, if (filp) ext4_error_file(filp, function, line, bh->b_blocknr, "bad entry in directory: %s - offset=%u, " - "inode=%u, rec_len=%d, name_len=%d, size=%d", + "inode=%u, rec_len=%d, size=%d fake=%d", error_msg, offset, le32_to_cpu(de->inode), - rlen, de->name_len, size); + rlen, size, fake); else ext4_error_inode(dir, function, line, bh->b_blocknr, "bad entry in directory: %s - offset=%u, " - "inode=%u, rec_len=%d, name_len=%d, size=%d", + "inode=%u, rec_len=%d, size=%d fake=%d", error_msg, offset, le32_to_cpu(de->inode), - rlen, de->name_len, size); + rlen, size, fake); return 1; } @@ -118,17 +134,15 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) struct buffer_head *bh = NULL; struct fscrypt_str fstr = FSTR_INIT(NULL, 0); - if (IS_ENCRYPTED(inode)) { - err = fscrypt_get_encryption_info(inode); - if (err) - return err; - } + err = fscrypt_prepare_readdir(inode); + if (err) + return err; if (is_dx_dir(inode)) { err = ext4_dx_readdir(file, ctx); - if (err != ERR_BAD_DX_DIR) { + if (err != ERR_BAD_DX_DIR) return err; - } + /* Can we just clear INDEX flag to ignore htree information? */ if (!ext4_has_metadata_csum(sb)) { /* @@ -148,7 +162,7 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) } if (IS_ENCRYPTED(inode)) { - err = fscrypt_fname_alloc_buffer(inode, EXT4_NAME_LEN, &fstr); + err = fscrypt_fname_alloc_buffer(EXT4_NAME_LEN, &fstr); if (err < 0) return err; } @@ -226,7 +240,8 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) * failure will be detected in the * dirent test below. */ if (ext4_rec_len_from_disk(de->rec_len, - sb->s_blocksize) < EXT4_DIR_REC_LEN(1)) + sb->s_blocksize) < ext4_dir_rec_len(1, + inode)) break; i += ext4_rec_len_from_disk(de->rec_len, sb->s_blocksize); @@ -267,7 +282,9 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) /* Directory is encrypted */ err = fscrypt_fname_disk_to_usr(inode, - 0, 0, &de_name, &fstr); + EXT4_DIRENT_HASH(de), + EXT4_DIRENT_MINOR_HASH(de), + &de_name, &fstr); de_name = fstr; fstr.len = save_len; if (err) @@ -286,7 +303,6 @@ static int ext4_readdir(struct file *file, struct dir_context *ctx) goto done; brelse(bh); bh = NULL; - offset = 0; } done: err = 0; @@ -392,11 +408,11 @@ struct fname { __u32 inode; __u8 name_len; __u8 file_type; - char name[0]; + char name[]; }; /* - * This functoin implements a non-recursive way of freeing all of the + * This function implements a non-recursive way of freeing all of the * nodes in the red-black tree. */ static void free_rb_tree_fname(struct rb_root *root) @@ -499,7 +515,7 @@ int ext4_htree_store_dirent(struct file *dir_file, __u32 hash, /* * This is a helper function for ext4_dx_readdir. It calls filldir - * for all entres on the fname linked list. (Normally there is only + * for all entries on the fname linked list. (Normally there is only * one entry on the linked list, unless there are 62 bit hash collisions.) */ static int call_filldir(struct file *file, struct dir_context *ctx, @@ -534,7 +550,7 @@ static int ext4_dx_readdir(struct file *file, struct dir_context *ctx) struct dir_private_info *info = file->private_data; struct inode *inode = file_inode(file); struct fname *fname; - int ret; + int ret = 0; if (!info) { info = ext4_htree_create_dir_info(file, ctx->pos); @@ -582,7 +598,7 @@ static int ext4_dx_readdir(struct file *file, struct dir_context *ctx) info->curr_minor_hash, &info->next_hash); if (ret < 0) - return ret; + goto finished; if (ret == 0) { ctx->pos = ext4_get_htree_eof(file); break; @@ -613,14 +629,7 @@ static int ext4_dx_readdir(struct file *file, struct dir_context *ctx) } finished: info->last_pos = ctx->pos; - return 0; -} - -static int ext4_dir_open(struct inode * inode, struct file * filp) -{ - if (IS_ENCRYPTED(inode)) - return fscrypt_get_encryption_info(inode) ? -EACCES : 0; - return 0; + return ret < 0 ? ret : 0; } static int ext4_release_dir(struct inode *inode, struct file *filp) @@ -639,7 +648,7 @@ int ext4_check_all_de(struct inode *dir, struct buffer_head *bh, void *buf, unsigned int offset = 0; char *top; - de = (struct ext4_dir_entry_2 *)buf; + de = buf; top = buf + buf_size; while ((char *) de < top) { if (ext4_check_dir_entry(dir, NULL, de, bh, @@ -664,57 +673,5 @@ const struct file_operations ext4_dir_operations = { .compat_ioctl = ext4_compat_ioctl, #endif .fsync = ext4_sync_file, - .open = ext4_dir_open, .release = ext4_release_dir, }; - -#ifdef CONFIG_UNICODE -static int ext4_d_compare(const struct dentry *dentry, unsigned int len, - const char *str, const struct qstr *name) -{ - struct qstr qstr = {.name = str, .len = len }; - const struct dentry *parent = READ_ONCE(dentry->d_parent); - const struct inode *inode = READ_ONCE(parent->d_inode); - - if (!inode || !IS_CASEFOLDED(inode) || - !EXT4_SB(inode->i_sb)->s_encoding) { - if (len != name->len) - return -1; - return memcmp(str, name->name, len); - } - - return ext4_ci_compare(inode, name, &qstr, false); -} - -static int ext4_d_hash(const struct dentry *dentry, struct qstr *str) -{ - const struct ext4_sb_info *sbi = EXT4_SB(dentry->d_sb); - const struct unicode_map *um = sbi->s_encoding; - const struct inode *inode = READ_ONCE(dentry->d_inode); - unsigned char *norm; - int len, ret = 0; - - if (!inode || !IS_CASEFOLDED(inode) || !um) - return 0; - - norm = kmalloc(PATH_MAX, GFP_ATOMIC); - if (!norm) - return -ENOMEM; - - len = utf8_casefold(um, str, norm, PATH_MAX); - if (len < 0) { - if (ext4_has_strict_mode(sbi)) - ret = -EINVAL; - goto out; - } - str->hash = full_name_hash(dentry, norm, len); -out: - kfree(norm); - return ret; -} - -const struct dentry_operations ext4_dentry_ops = { - .d_hash = ext4_d_hash, - .d_compare = ext4_d_compare, -}; -#endif |