[PATCH 6.6.y] mm/damon/tests/core-kunit: handle memory failure from damon_test_target()

[PATCH 6.6.y] mm/damon/tests/core-kunit: handle memory failure from damon_test_target()

[SeongJae Park]

damon_test_target() is assuming all dynamic memory allocation in it will
succeed.  Those are indeed likely in the real use cases since those
allocations are too small to fail, but theoretically those could fail.  In
the case, inappropriate memory access can happen.  Fix it by appropriately
cleanup pre-allocated memory and skip the execution of the remaining tests
in the failure cases.

Link: https://lkml.kernel.org/r/20251101182021.74868-4-sj@kernel.org
Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: Brendan Higgins <brendan.higgins@linux.dev>
Cc: David Gow <davidgow@google.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: <stable@vger.kernel.org>	[5.15+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit fafe953de2c661907c94055a2497c6b8dbfd26f3)
---
 mm/damon/core-test.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index 6cc8b245586d..0ef2324e3422 100644
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -52,7 +52,14 @@ static void damon_test_target(struct kunit *test)
 	struct damon_ctx *c = damon_new_ctx();
 	struct damon_target *t;
 
+	if (!c)
+		kunit_skip(test, "ctx alloc fail");
+
 	t = damon_new_target();
+	if (!t) {
+		damon_destroy_ctx(c);
+		kunit_skip(test, "target alloc fail");
+	}
 	KUNIT_EXPECT_EQ(test, 0u, nr_damon_targets(c));
 
 	damon_add_target(c, t);
-- 
2.47.3