[PATCHSET v30.1 14/15] xfs: inode-related repair fixes

Darrick J. Wong
2024-03-27T01:49:58Z

Hi all,

While doing QA of the online fsck code, I made a few observations:
First, nobody was checking that the di_onlink field is actually zero;
Second, that allocating a temporary file for repairs can fail (and
thus bring down the entire fs) if the inode cluster is corrupt; and
Third, that file link counts do not pin at ~0U to prevent integer
overflows. Fourth, the x{chk,rep}_metadata_inode_fork functions
should be subclassing the main scrub context, not modifying the
parent's setup willy-nilly.

This scattered patchset fixes those three problems.

If you're going to start using this code, I strongly recommend pulling
from my git trees, which are linked below.

This has been running on the djcloud for months with no problems. Enjoy!
Comments and questions are, as always, welcome.

--D

kernel git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=inode-repair-improvements

xfsprogs git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfsprogs-dev.git/log/?h=inode-repair-improvements
---
Commits in this patchset:
* xfs: check unused nlink fields in the ondisk inode
* xfs: try to avoid allocating from sick inode clusters
* xfs: pin inodes that would otherwise overflow link count
* xfs: create subordinate scrub contexts for xchk_metadata_inode_subtype
---
fs/xfs/libxfs/xfs_format.h | 6 ++++
fs/xfs/libxfs/xfs_ialloc.c | 40 ++++++++++++++++++++++++
fs/xfs/libxfs/xfs_inode_buf.c | 8 +++++
fs/xfs/scrub/common.c | 23 ++------------
fs/xfs/scrub/dir_repair.c | 11 ++-----
fs/xfs/scrub/inode_repair.c | 12 +++++++
fs/xfs/scrub/nlinks.c | 4 ++
fs/xfs/scrub/nlinks_repair.c | 8 +----
fs/xfs/scrub/repair.c | 67 ++++++++---------------------------------
fs/xfs/scrub/scrub.c | 63 +++++++++++++++++++++++++++++++++++++++
fs/xfs/scrub/scrub.h | 11 +++++++
fs/xfs/xfs_inode.c | 33 +++++++++++++-------
12 files changed, 187 insertions(+), 99 deletions(-)