xfs: btree format ifork loader should check for zero numrecs
authorDarrick J. Wong <darrick.wong@oracle.com>
Wed, 17 Jan 2018 02:54:13 +0000 (18:54 -0800)
committerDarrick J. Wong <darrick.wong@oracle.com>
Thu, 18 Jan 2018 05:00:46 +0000 (21:00 -0800)
commit55e45429ce3e4ac9dd2bf4937b1a499a69ccc4ca
tree88ea8bcc1c3ffaa721c478044304707d2fff8835
parent79a69bf8dc240ebeb105226a8a8540df136bf987
xfs: btree format ifork loader should check for zero numrecs

A btree format inode fork with zero records makes no sense, so reject it
if we see it, or else we can miscalculate memory allocations.  Found by
zeroes fuzzing {a,u3}.bmbt.numrecs in xfs/{374,378,412} with KASAN.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
fs/xfs/libxfs/xfs_inode_fork.c