From 93563bb161f31c1e3642480de5f12445e6938025 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 1 Sep 2021 10:40:09 -0700 Subject: 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: Darrick J. Wong --- fs/xfs/scrub/btree.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 48 insertions(+), 1 deletion(-) diff --git a/fs/xfs/scrub/btree.c b/fs/xfs/scrub/btree.c index eccb855dc904..bd777a2444e8 100644 --- a/fs/xfs/scrub/btree.c +++ b/fs/xfs/scrub/btree.c @@ -516,6 +516,48 @@ 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_ptrs[level + 1], + 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_ptrs[level + 1], + 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. @@ -567,7 +609,12 @@ 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; } /* -- cgit v1.2.3