diff options
Diffstat (limited to 'fs/ext4/dir.c')
| -rw-r--r-- | fs/ext4/dir.c | 40 |
1 files changed, 23 insertions, 17 deletions
diff --git a/fs/ext4/dir.c b/fs/ext4/dir.c index ece76fb6a40c..bd5d74d06399 100644 --- a/fs/ext4/dir.c +++ b/fs/ext4/dir.c @@ -60,7 +60,11 @@ static unsigned char get_dtype(struct super_block *sb, int filetype) return (ext4_filetype_table[filetype]); } - +/* + * Return 0 if the directory entry is OK, and 1 if there is a problem + * + * Note: this is the opposite of what ext2 and ext3 historically returned... + */ int __ext4_check_dir_entry(const char *function, unsigned int line, struct inode *dir, struct ext4_dir_entry_2 *de, @@ -71,26 +75,28 @@ 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); - if (rlen < EXT4_DIR_REC_LEN(1)) + if (unlikely(rlen < EXT4_DIR_REC_LEN(1))) error_msg = "rec_len is smaller than minimal"; - else if (rlen % 4 != 0) + else if (unlikely(rlen % 4 != 0)) error_msg = "rec_len % 4 != 0"; - else if (rlen < EXT4_DIR_REC_LEN(de->name_len)) + else if (unlikely(rlen < EXT4_DIR_REC_LEN(de->name_len))) error_msg = "rec_len is too small for name_len"; - else if (((char *) de - bh->b_data) + rlen > dir->i_sb->s_blocksize) + else if (unlikely(((char *) de - bh->b_data) + rlen > + dir->i_sb->s_blocksize)) error_msg = "directory entry across blocks"; - else if (le32_to_cpu(de->inode) > - le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count)) + else if (unlikely(le32_to_cpu(de->inode) > + le32_to_cpu(EXT4_SB(dir->i_sb)->s_es->s_inodes_count))) error_msg = "inode out of bounds"; + else + return 0; - if (error_msg != NULL) - ext4_error_inode(dir, function, line, bh->b_blocknr, - "bad entry in directory: %s - " - "offset=%u(%u), inode=%u, rec_len=%d, name_len=%d", - error_msg, (unsigned) (offset%bh->b_size), offset, - le32_to_cpu(de->inode), - rlen, de->name_len); - return error_msg == NULL ? 1 : 0; + ext4_error_inode(dir, function, line, bh->b_blocknr, + "bad entry in directory: %s - " + "offset=%u(%u), inode=%u, rec_len=%d, name_len=%d", + error_msg, (unsigned) (offset%bh->b_size), offset, + le32_to_cpu(de->inode), + rlen, de->name_len); + return 1; } static int ext4_readdir(struct file *filp, @@ -194,8 +200,8 @@ revalidate: while (!error && filp->f_pos < inode->i_size && offset < sb->s_blocksize) { de = (struct ext4_dir_entry_2 *) (bh->b_data + offset); - if (!ext4_check_dir_entry(inode, de, - bh, offset)) { + if (ext4_check_dir_entry(inode, de, + bh, offset)) { /* * On error, skip the f_pos to the next block */ |