mm/damon/tests/core-kunit: handle alloc failures in damon_test_set_regions()

commit 74d5969995d129fd59dd93b9c7daa6669cb6810f upstream.

damon_test_set_regions() 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/20251101182021.74868-11-sj@kernel.org
Fixes: 62f409560eb2 ("mm/damon/core-test: test damon_set_regions")
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>	[6.1+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/mm/damon/core-test.h b/mm/damon/core-test.h
index 409d926e5630d6d4bc90cc186d0aa9f25d8c2c6e..e71d50f0a2dfbe63e480b2e22a83d779f21b9644 100644 (file)
--- a/mm/damon/core-test.h
+++ b/mm/damon/core-test.h
@@ -341,13 +341,26 @@ static void damon_test_ops_registration(struct kunit *test)
 static void damon_test_set_regions(struct kunit *test)
 {
        struct damon_target *t = damon_new_target();
-       struct damon_region *r1 = damon_new_region(4, 16);
-       struct damon_region *r2 = damon_new_region(24, 32);
+       struct damon_region *r1, *r2;
        struct damon_addr_range range = {.start = 8, .end = 28};
        unsigned long expects[] = {8, 16, 16, 24, 24, 28};
        int expect_idx = 0;
        struct damon_region *r;
 
+       if (!t)
+               kunit_skip(test, "target alloc fail");
+       r1 = damon_new_region(4, 16);
+       if (!r1) {
+               damon_free_target(t);
+               kunit_skip(test, "region alloc fail");
+       }
+       r2 = damon_new_region(24, 32);
+       if (!r2) {
+               damon_free_target(t);
+               damon_free_region(r1);
+               kunit_skip(test, "second region alloc fail");
+       }
+
        damon_add_region(r1, t);
        damon_add_region(r2, t);
        damon_set_regions(t, &range, 1);