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>
This commit is contained in:
Darrick J. Wong 2020-09-21 09:15:09 -07:00
parent 8df0fa39bd
commit e581c9397a

View File

@ -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: