xfs: btree lookup shouldn't ASSERT on empty btree nodes
If a btree lookup encounters an empty btree node or an empty btree leaf
on a multi-level btree, that's evidence of a corrupt on-disk btree.
Therefore, we should return -EFSCORRUPTED to the upper levels, not an
ASSERT failure.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index c825c81..3d59eb6 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -1896,7 +1896,12 @@ xfs_btree_lookup(
high = xfs_btree_get_numrecs(block);
if (!high) {
/* Block is empty, must be an empty leaf. */
- ASSERT(level == 0 && cur->bc_nlevels == 1);
+ if (level != 0 || cur->bc_nlevels != 1) {
+ XFS_CORRUPTION_ERROR(__func__,
+ XFS_ERRLEVEL_LOW,
+ cur->bc_mp, block);
+ return -EFSCORRUPTED;
+ }
cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE;
*stat = 0;