diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/namei.c | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index 4d9901a18b97..f6bc19e638dc 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -3318,6 +3318,9 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, struct buffer_head *bh; if (!ext4_has_inline_data(inode)) { + struct ext4_dir_entry_2 *de; + unsigned int offset; + /* The first directory block must not be a hole, so * treat it as DIRENT_HTREE */ @@ -3326,9 +3329,30 @@ static struct buffer_head *ext4_get_first_dir_block(handle_t *handle, *retval = PTR_ERR(bh); return NULL; } - *parent_de = ext4_next_entry( - (struct ext4_dir_entry_2 *)bh->b_data, - inode->i_sb->s_blocksize); + + de = (struct ext4_dir_entry_2 *) bh->b_data; + if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, + bh->b_size, 0) || + le32_to_cpu(de->inode) != inode->i_ino || + strcmp(".", de->name)) { + EXT4_ERROR_INODE(inode, "directory missing '.'"); + brelse(bh); + *retval = -EFSCORRUPTED; + return NULL; + } + offset = ext4_rec_len_from_disk(de->rec_len, + inode->i_sb->s_blocksize); + de = ext4_next_entry(de, inode->i_sb->s_blocksize); + if (ext4_check_dir_entry(inode, NULL, de, bh, bh->b_data, + bh->b_size, offset) || + le32_to_cpu(de->inode) == 0 || strcmp("..", de->name)) { + EXT4_ERROR_INODE(inode, "directory missing '..'"); + brelse(bh); + *retval = -EFSCORRUPTED; + return NULL; + } + *parent_de = de; + return bh; } |