diff options
| -rw-r--r-- | fs/ext4/extents.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 2a2eef9c14e4..2f258c68d3e0 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -381,9 +381,13 @@ static int ext4_valid_extent(struct inode *inode, struct ext4_extent *ext) ext4_fsblk_t block = ext4_ext_pblock(ext); int len = ext4_ext_get_actual_len(ext); ext4_lblk_t lblock = le32_to_cpu(ext->ee_block); - ext4_lblk_t last = lblock + len - 1; - if (len == 0 || lblock > last) + /* + * We allow neither: + * - zero length + * - overflow/wrap-around + */ + if (lblock + len <= lblock) return 0; return ext4_data_block_valid(EXT4_SB(inode->i_sb), block, len); } |