mm/damon/tests/core-kunit: handle alloc failures on dasmon_test_merge_regions_of()

commit 0998d2757218771c59d5ca59ccf13d1542a38f17 upstream.

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.

Link: https://lkml.kernel.org/r/20251101182021.74868-8-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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/damon/tests/core-kunit.h b/mm/damon/tests/core-kunit.h
index 2fc66d1a0d27cd05aa1727a1e51afa3faa68f037..f6b74a35766ec17a8c6c575772fc87886113bead 100644 (file)
--- a/mm/damon/tests/core-kunit.h
+++ b/mm/damon/tests/core-kunit.h
@@ -238,8 +238,14 @@ 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);