Re: [RFC PATCH bpf-next v4 11/12] selftests/bpf: Add test for memcg_bpf_ops hierarchies
From: bot+bpf-ci@kernel.org
Date: 2026-01-26 09:30:24
Also in:
bpf, cgroups, linux-kselftest, linux-mm, lkml
quoted hunk ↗ jump to hunk
diff --git a/tools/testing/selftests/bpf/prog_tests/memcg_ops.c b/tools/testing/selftests/bpf/prog_tests/memcg_ops.c index a019ba2387bc..08ac97752ac9 100644 --- a/tools/testing/selftests/bpf/prog_tests/memcg_ops.c +++ b/tools/testing/selftests/bpf/prog_tests/memcg_ops.c@@ -539,3 +539,73 @@ void test_memcg_ops_below_min_over_high(void)
[ ... ]
+void test_memcg_ops_hierarchies(void)
+{
+ int ret, first = -1, second = -1, third = -1;
+ struct memcg_ops *skel;^^^^ Should skel be initialized to NULL here? The other tests in this file (test_memcg_ops_over_high, test_memcg_ops_below_low_over_high, and test_memcg_ops_below_min_over_high) all initialize their skeleton pointers to NULL. If any of the early checks fail (e.g. setup_cgroup_environment() or create_and_get_cgroup()), the code jumps to cleanup where memcg_ops__detach() is called. The skeleton __detach() function dereferences its argument without checking for NULL, which would cause a crash with an uninitialized pointer.
+ struct bpf_map *map; + struct bpf_link *link1 = NULL, *link2 = NULL, *link3 = NULL; + DECLARE_LIBBPF_OPTS(bpf_struct_ops_opts, opts); + + ret = setup_cgroup_environment(); + if (!ASSERT_OK(ret, "setup_cgroup_environment")) + goto cleanup;
[ ... ]
+cleanup: + bpf_link__destroy(link1); + bpf_link__destroy(link2); + bpf_link__destroy(link3); + memcg_ops__detach(skel);
^^^^ This dereferences skel without checking if it was ever assigned.
+ close(first); + close(second); + close(third); + cleanup_cgroup_environment(); +}
--- AI reviewed your patch. Please fix the bug or email reply why it's not a bug. See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md CI run summary: https://github.com/kernel-patches/bpf/actions/runs/21352241149