ext4: check for zero length extent explicitly
[ Upstream commit
2f974865ffdfe7b9f46a9940836c8b167342563d ]
The following commit introduced a bug when checking for zero length extent
5946d08 ext4: check for overlapping extents in ext4_valid_extent_entries()
Zero length extent could pass the check if lblock is zero.
Adding the explicit check for zero length back.
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>