mm/damon/tests/core-kunit: handle alloc failures on damon_test_set_filters_default_re...

damon_test_set_filters_default_reject() 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/20251101182021.74868-17-sj@kernel.org
Fixes: 094fb14913c7 ("mm/damon/tests/core-kunit: add a test for damos_set_filters_default_reject()")
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>	[6.16+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index a03ae9d..a91d798 100644 (file)
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -659,6 +659,8 @@ static void damon_test_set_filters_default_reject(struct kunit *test)
        KUNIT_EXPECT_EQ(test, scheme.ops_filters_default_reject, false);
 
        target_filter = damos_new_filter(DAMOS_FILTER_TYPE_TARGET, true, true);
+       if (!target_filter)
+               kunit_skip(test, "filter alloc fail");
        damos_add_filter(&scheme, target_filter);
        damos_set_filters_default_reject(&scheme);
        /*
@@ -684,6 +686,10 @@ static void damon_test_set_filters_default_reject(struct kunit *test)
        KUNIT_EXPECT_EQ(test, scheme.ops_filters_default_reject, false);
 
        anon_filter = damos_new_filter(DAMOS_FILTER_TYPE_ANON, true, true);
+       if (!anon_filter) {
+               damos_free_filter(target_filter);
+               kunit_skip(test, "anon_filter alloc fail");
+       }
        damos_add_filter(&scheme, anon_filter);
 
        damos_set_filters_default_reject(&scheme);