damon_test_merge_regions_of() 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.

Fixes: 17ccae8bb5c9 ("mm/damon: add kunit tests")
Cc: <stable@vger.kernel.org> # 5.15.x
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/tests/core-kunit.h | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index e8219fd23318..98f2a3de7cea 100644
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -248,8 +248,14 @@ static void damon_test_merge_regions_of(struct kunit *test)
 	int i;
 
 	t = damon_new_target();
+	if (!t)
+		kunit_skip(test, "target alloc fail");
 	for (i = 0; i < ARRAY_SIZE(sa); i++) {
 		r = damon_new_region(sa[i], ea[i]);
+		if (!r) {
+			damon_free_target(t);
+			kunit_skip(test, "region alloc fail");
+		}
 		r->nr_accesses = nrs[i];
 		r->nr_accesses_bp = nrs[i] * 10000;
 		damon_add_region(r, t);
-- 
2.47.3