6.1-stable review patch. If anyone has any objections, please let me know.
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From: Dave Chinner dchinner@redhat.com
commit 7930d9e103700cde15833638855b750715c12091 upstream.
Because on v3 inodes, di_flushiter doesn't exist. It overlaps with zero padding in the inode, except when NREXT64=1 configurations are in use and the zero padding is no longer padding but holds the 64 bit extent counter.
This manifests obviously on big endian platforms (e.g. s390) because the log dinode is in host order and the overlap is the LSBs of the extent count field. It is not noticed on little endian machines because the overlap is at the MSB end of the extent count field and we need to get more than 2^^48 extents in the inode before it manifests. i.e. the heat death of the universe will occur before we see the problem in little endian machines.
This is a zero-day issue for NREXT64=1 configuraitons on big endian machines. Fix it by only clearing di_flushiter on v2 inodes during recovery.
Fixes: 9b7d16e34bbe ("xfs: Introduce XFS_DIFLAG2_NREXT64 and associated helpers") cc: stable@kernel.org # 5.19+ Signed-off-by: Dave Chinner dchinner@redhat.com Reviewed-by: "Darrick J. Wong" djwong@kernel.org Signed-off-by: Chandan Babu R chandanbabu@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/xfs/xfs_inode_item_recover.c | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-)
--- a/fs/xfs/xfs_inode_item_recover.c +++ b/fs/xfs/xfs_inode_item_recover.c @@ -369,24 +369,26 @@ xlog_recover_inode_commit_pass2( * superblock flag to determine whether we need to look at di_flushiter * to skip replay when the on disk inode is newer than the log one */ - if (!xfs_has_v3inodes(mp) && - ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) { - /* - * Deal with the wrap case, DI_MAX_FLUSH is less - * than smaller numbers - */ - if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH && - ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) { - /* do nothing */ - } else { - trace_xfs_log_recover_inode_skip(log, in_f); - error = 0; - goto out_release; + if (!xfs_has_v3inodes(mp)) { + if (ldip->di_flushiter < be16_to_cpu(dip->di_flushiter)) { + /* + * Deal with the wrap case, DI_MAX_FLUSH is less + * than smaller numbers + */ + if (be16_to_cpu(dip->di_flushiter) == DI_MAX_FLUSH && + ldip->di_flushiter < (DI_MAX_FLUSH >> 1)) { + /* do nothing */ + } else { + trace_xfs_log_recover_inode_skip(log, in_f); + error = 0; + goto out_release; + } } + + /* Take the opportunity to reset the flush iteration count */ + ldip->di_flushiter = 0; }
- /* Take the opportunity to reset the flush iteration count */ - ldip->di_flushiter = 0;
if (unlikely(S_ISREG(ldip->di_mode))) { if ((ldip->di_format != XFS_DINODE_FMT_EXTENTS) &&