diff options
| author | Darrick J. Wong | 2014-07-28 13:06:26 -0400 |
|---|---|---|
| committer | Theodore Ts'o | 2014-07-28 13:06:26 -0400 |
| commit | 40b163f1c45f52752677e66d2fd273dbfd273a22 (patch) | |
| tree | 9047b84d0ab4086388c351d2f49e3ed1fba576d0 | |
| parent | 6e2631463f3a2ce430a295c68aead3ff228ca3cf (diff) | |
ext4: check inline directory before converting
Before converting an inline directory to a regular directory, check
the directory entries to make sure they're not obviously broken.
This helps us to avoid a BUG_ON if one of the dirents is trashed.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
| -rw-r--r-- | fs/ext4/dir.c | 25 | ||||
| -rw-r--r-- | fs/ext4/ext4.h | 2 | ||||
| -rw-r--r-- | fs/ext4/inline.c | 12 |
3 files changed, 39 insertions, 0 deletions
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index ef1bed66c14f..0bb3f9ea0832 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -571,6 +571,31 @@ static int ext4_release_dir(struct inode *inode, struct file *filp) return 0; } +int ext4_check_all_de(struct inode *dir, struct buffer_head *bh, void *buf, + int buf_size) +{ + struct ext4_dir_entry_2 *de; + int nlen, rlen; + unsigned int offset = 0; + char *top; + + de = (struct ext4_dir_entry_2 *)buf; + top = buf + buf_size; + while ((char *) de < top) { + if (ext4_check_dir_entry(dir, NULL, de, bh, + buf, buf_size, offset)) + return -EIO; + nlen = EXT4_DIR_REC_LEN(de->name_len); + rlen = ext4_rec_len_from_disk(de->rec_len, buf_size); + de = (struct ext4_dir_entry_2 *)((char *)de + rlen); + offset += rlen; + } + if ((char *) de > top) + return -EIO; + + return 0; +} + const struct file_operations ext4_dir_operations = { .llseek = ext4_dir_llseek, .read = generic_read_dir, diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 321760d6b353..5b19760b1de5 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -2028,6 +2028,8 @@ static inline unsigned char get_dtype(struct super_block *sb, int filetype) return ext4_filetype_table[filetype]; } +extern int ext4_check_all_de(struct inode *dir, struct buffer_head *bh, + void *buf, int buf_size); /* fsync.c */ extern int ext4_sync_file(struct file *, loff_t, loff_t, int); diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index 141b6acbc51c..bea662bd0ca6 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -1172,6 +1172,18 @@ static int ext4_convert_inline_data_nolock(handle_t *handle, if (error < 0) goto out; + /* + * Make sure the inline directory entries pass checks before we try to + * convert them, so that we avoid touching stuff that needs fsck. + */ + if (S_ISDIR(inode->i_mode)) { + error = ext4_check_all_de(inode, iloc->bh, + buf + EXT4_INLINE_DOTDOT_SIZE, + inline_size - EXT4_INLINE_DOTDOT_SIZE); + if (error) + goto out; + } + error = ext4_destroy_inline_data_nolock(handle, inode); if (error) goto out; |