linux-kernel - [RFC PATCH 2/2] mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250826033653.1208227-3-yanquanmin1@huawei.com>
Date: Tue, 26 Aug 2025 11:36:53 +0800
From: Quanmin Yan <yanquanmin1@...wei.com>
To: <sj@...nel.org>
CC: <akpm@...ux-foundation.org>, <damon@...ts.linux.dev>,
	<linux-kernel@...r.kernel.org>, <linux-mm@...ck.org>,
	<yanquanmin1@...wei.com>, <wangkefeng.wang@...wei.com>, <zuoze1@...wei.com>
Subject: [RFC PATCH 2/2] mm/damon/reclaim: avoid divide-by-zero in damon_reclaim_apply_parameters()

When creating a new scheme of DAMON_RECLAIM, the calculation
of 'min_age_region' uses 'aggr_interval' as the divisor, which
may lead to division-by-zero errors. Fix it by directly returning
-EINVAL when such a case occurs.

Fixes: f5a79d7c0c87 ("mm/damon: introduce struct damos_access_pattern")
Signed-off-by: Quanmin Yan <yanquanmin1@...wei.com>
---
 mm/damon/reclaim.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/mm/damon/reclaim.c b/mm/damon/reclaim.c
index 3c71b4596676..fb7c982a0018 100644
--- a/mm/damon/reclaim.c
+++ b/mm/damon/reclaim.c
@@ -194,6 +194,11 @@ static int damon_reclaim_apply_parameters(void)
 	if (err)
 		return err;
 
+	if (!damon_reclaim_mon_attrs.aggr_interval) {
+		err = -EINVAL;
+		goto out;
+	}
+
 	err = damon_set_attrs(param_ctx, &damon_reclaim_mon_attrs);
 	if (err)
 		goto out;
-- 
2.43.0