Commit e581c939 authored Sep 21, 2020 by Darrick J. Wong

xfs: check dabtree node hash values when loading child blocks



When xchk_da_btree_block is loading a non-root dabtree block, we know
that the parent block had to have a (hashval, address) pointer to the
block that we just loaded.  Check that the hashval in the parent matches
the block we just loaded.

This was found by fuzzing nbtree[3].hashval = ones in xfs/394.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>

parent 8df0fa39

fs/xfs/scrub/dabtree.c

+14 −0

Original line number	Diff line number	Diff line
		@@ -441,6 +441,20 @@ xchk_da_btree_block(
		goto out_freebp;
		}

		/*
		* If we've been handed a block that is below the dabtree root, does
		* its hashval match what the parent block expected to see?
		*/
		if (level > 0) {
		struct xfs_da_node_entry *key;

		key = xchk_da_btree_node_entry(ds, level - 1);
		if (be32_to_cpu(key->hashval) != blk->hashval) {
		xchk_da_set_corrupt(ds, level);
		goto out_freebp;
		}
		}

		out:
		return error;
		out_freebp: