[PATCH 5.10.y] xfs: allow softlimit with no hardlimit in quota scrub

[Sasha Levin <sashal@kernel.org>]

From: "Darrick J. Wong" <djwong@kernel.org>

[ Upstream commit 342c2e00b3a99099a7088f7b8c8f075670c603a9 ]

LOLLM observes that the sysadmin can set a user's soft limit to a
nonzero value and the hard limit to zero, so those aren't corruptions.

Cc: stable@vger.kernel.org # v4.15
Fixes: c2fc338c87a31f ("xfs: scrub quota information")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Assisted-by: LOLLM # finding obvious bugs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
[ sashal: omitted the quota repair changes in xrep_quota_item() ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/xfs/scrub/quota.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/xfs/scrub/quota.c b/fs/xfs/scrub/quota.c
index e34ca20ae8e40..42cccc6505f76 100644
--- a/fs/xfs/scrub/quota.c
+++ b/fs/xfs/scrub/quota.c
@@ -103,21 +103,21 @@ xchk_quota_item(
 	 * suspect, which is why we flag it for review.
 	 *
 	 * Complain about corruption if the soft limit is greater than
-	 * the hard limit.
+	 * the hard limit and there's a hard limit set.
 	 */
 	if (dq->q_blk.hardlimit > mp->m_sb.sb_dblocks)
 		xchk_fblock_set_warning(sc, XFS_DATA_FORK, offset);
-	if (dq->q_blk.softlimit > dq->q_blk.hardlimit)
+	if (dq->q_blk.hardlimit && dq->q_blk.softlimit > dq->q_blk.hardlimit)
 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
 
 	if (dq->q_ino.hardlimit > M_IGEO(mp)->maxicount)
 		xchk_fblock_set_warning(sc, XFS_DATA_FORK, offset);
-	if (dq->q_ino.softlimit > dq->q_ino.hardlimit)
+	if (dq->q_ino.hardlimit && dq->q_ino.softlimit > dq->q_ino.hardlimit)
 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
 
 	if (dq->q_rtb.hardlimit > mp->m_sb.sb_rblocks)
 		xchk_fblock_set_warning(sc, XFS_DATA_FORK, offset);
-	if (dq->q_rtb.softlimit > dq->q_rtb.hardlimit)
+	if (dq->q_rtb.hardlimit && dq->q_rtb.softlimit > dq->q_rtb.hardlimit)
 		xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, offset);
 
 	/* Check the resource counts. */
-- 
2.53.0