Commit c99f99fa authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: check btree keys reflect the child block 



When scrub is checking a non-root btree block, it should make sure that
the keys in the parent btree block accurately capture the keyspace that
the child block stores.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarDave Chinner <dchinner@redhat.com>
parent 38384569

fs/xfs/scrub/btree.c

+48 −1
Original line number Diff line number Diff line
@@ -529,6 +529,48 @@ xchk_btree_check_minrecs( 
		xchk_btree_set_corrupt(bs->sc, cur, level);

}



/*

 * If this btree block has a parent, make sure that the parent's keys capture

 * the keyspace contained in this block.

 */

STATIC void

xchk_btree_block_check_keys(

	struct xchk_btree	*bs,

	int			level,

	struct xfs_btree_block	*block)

{

	union xfs_btree_key	block_key;

	union xfs_btree_key	*block_high_key;

	union xfs_btree_key	*parent_low_key, *parent_high_key;

	struct xfs_btree_cur	*cur = bs->cur;

	struct xfs_btree_block	*parent_block;

	struct xfs_buf		*bp;



	if (level == cur->bc_nlevels - 1)

		return;



	xfs_btree_get_keys(cur, block, &block_key);



	/* Make sure the low key of this block matches the parent. */

	parent_block = xfs_btree_get_block(cur, level + 1, &bp);

	parent_low_key = xfs_btree_key_addr(cur, cur->bc_levels[level + 1].ptr,

			parent_block);

	if (cur->bc_ops->diff_two_keys(cur, &block_key, parent_low_key)) {

		xchk_btree_set_corrupt(bs->sc, bs->cur, level);

		return;

	}



	if (!(cur->bc_flags & XFS_BTREE_OVERLAPPING))

		return;



	/* Make sure the high key of this block matches the parent. */

	parent_high_key = xfs_btree_high_key_addr(cur,

			cur->bc_levels[level + 1].ptr, parent_block);

	block_high_key = xfs_btree_high_key_from_key(cur, &block_key);

	if (cur->bc_ops->diff_two_keys(cur, block_high_key, parent_high_key))

		xchk_btree_set_corrupt(bs->sc, bs->cur, level);

}



/*

 * Grab and scrub a btree block given a btree pointer.  Returns block

 * and buffer pointers (if applicable) if they're ok to use.
@@ -580,7 +622,12 @@ xchk_btree_get_block( 
	 * Check the block's siblings; this function absorbs error codes

	 * for us.

	 */

	return xchk_btree_block_check_siblings(bs, *pblock);

	error = xchk_btree_block_check_siblings(bs, *pblock);

	if (error)

		return error;



	xchk_btree_block_check_keys(bs, level, *pblock);

	return 0;

}



/*