[RFC PATCH] mm/damon/sysfs-schemes: call missing mem_cgroup_iter_break()

From: SeongJae Park

Date: Sat Apr 25 2026 - 16:25:03 EST


damon_sysfs_memcg_path_to_id() breaks mem_cgroup_iter() loop without
calling mem_cgroup_iter_break(). This leaks the cgroup reference. Fix
the issue by calling mem_cgroup_iter_break() before the break.

The issue was discovered [1] by Sashiko.

[1] https://lore.kernel.org/20260423004148.74722-1-sj@xxxxxxxxxx

Fixes: 29cbb9a13f05 ("mm/damon/sysfs-schemes: implement scheme filters")
Cc: <stable@xxxxxxxxxxxxxxx> # 6.3.x
Signed-off-by: SeongJae Park <sj@xxxxxxxxxx>
---
mm/damon/sysfs-schemes.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index 245d63808411a..04746cbb33272 100644
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -2594,6 +2594,7 @@ static int damon_sysfs_memcg_path_to_id(char *memcg_path, u64 *id)
if (damon_sysfs_memcg_path_eq(memcg, path, memcg_path)) {
*id = mem_cgroup_id(memcg);
found = true;
+ mem_cgroup_iter_break(NULL, memcg);
break;
}
}

base-commit: 8aa462c5a7540f9f8882cf8fa6add712fdf38c91
--
2.47.3