From da062d16a897c0759ae907e786bc0bea950c0c9d Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 12 Jul 2021 12:58:47 -0700 Subject: xfs: check for sparse inode clusters that cross new EOAG when shrinking While running xfs/168, I noticed occasional write verifier shutdowns involving inodes at the very end of the filesystem. Existing inode btree validation code checks that all inode clusters are fully contained within the filesystem. However, due to inadequate checking in the fs shrink code, it's possible that there could be a sparse inode cluster at the end of the filesystem where the upper inodes of the cluster are marked as holes and the corresponding blocks are free. In this case, the last blocks in the AG are listed in the bnobt. This enables the shrink to proceed but results in a filesystem that trips the inode verifiers. Fix this by disallowing the shrink. Signed-off-by: Darrick J. Wong Reviewed-by: Gao Xiang --- fs/xfs/libxfs/xfs_ag.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'fs/xfs/libxfs/xfs_ag.c') diff --git a/fs/xfs/libxfs/xfs_ag.c b/fs/xfs/libxfs/xfs_ag.c index 778ec52cce70..ee9ec0c50bec 100644 --- a/fs/xfs/libxfs/xfs_ag.c +++ b/fs/xfs/libxfs/xfs_ag.c @@ -803,6 +803,14 @@ xfs_ag_shrink_space( args.fsbno = XFS_AGB_TO_FSB(mp, agno, aglen - delta); + /* + * Make sure that the last inode cluster cannot overlap with the new + * end of the AG, even if it's sparse. + */ + error = xfs_ialloc_check_shrink(*tpp, agno, agibp, aglen - delta); + if (error) + return error; + /* * Disable perag reservations so it doesn't cause the allocation request * to fail. We'll reestablish reservation before we return. -- cgit v1.2.3