If the caller passes in a cursor to a zero-height btree (which is impossible), we never set block to anything but NULL, which causes the later dereference of it to crash. Instead, just return -EFSCORRUPTED. Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> --- libxfs/xfs_btree.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/libxfs/xfs_btree.c b/libxfs/xfs_btree.c index 8391078..cb671f6 100644 --- a/libxfs/xfs_btree.c +++ b/libxfs/xfs_btree.c @@ -1810,6 +1810,10 @@ xfs_btree_lookup( XFS_BTREE_STATS_INC(cur, lookup); + /* No such thing as a zero-level tree. */ + if (cur->bc_nlevels == 0) + return -EFSCORRUPTED; + block = NULL; keyno = 0; -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
