Commit a32f6f17 authored by KaFai Wan's avatar KaFai Wan Committed by Alexei Starovoitov
Browse files

selftests/bpf: Add selftest for attaching tracing programs to functions in deny list 



The result:

 $ tools/testing/selftests/bpf/test_progs -t tracing_failure/tracing_deny
 #468/3   tracing_failure/tracing_deny:OK
 #468     tracing_failure:OK
 Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: default avatarKaFai Wan <kafai.wan@linux.dev>
Acked-by: default avatarYonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20250724151454.499040-4-kafai.wan@linux.dev


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 863aab3d

tools/testing/selftests/bpf/prog_tests/tracing_failure.c

+33 −0
Original line number Diff line number Diff line
@@ -28,10 +28,43 @@ static void test_bpf_spin_lock(bool is_spin_lock) 
	tracing_failure__destroy(skel);

}



static void test_tracing_deny(void)

{

	struct tracing_failure *skel;

	char log_buf[256];

	int btf_id, err;



	/* __rcu_read_lock depends on CONFIG_PREEMPT_RCU */

	btf_id = libbpf_find_vmlinux_btf_id("__rcu_read_lock", BPF_TRACE_FENTRY);

	if (btf_id <= 0) {

		test__skip();

		return;

	}



	skel = tracing_failure__open();

	if (!ASSERT_OK_PTR(skel, "tracing_failure__open"))

		return;



	bpf_program__set_autoload(skel->progs.tracing_deny, true);

	bpf_program__set_log_buf(skel->progs.tracing_deny, log_buf, sizeof(log_buf));



	err = tracing_failure__load(skel);

	if (!ASSERT_ERR(err, "tracing_failure__load"))

		goto out;



	ASSERT_HAS_SUBSTR(log_buf,

			  "Attaching tracing programs to function '__rcu_read_lock' is rejected.",

			  "log_buf");

out:

	tracing_failure__destroy(skel);

}



void test_tracing_failure(void)

{

	if (test__start_subtest("bpf_spin_lock"))

		test_bpf_spin_lock(true);

	if (test__start_subtest("bpf_spin_unlock"))

		test_bpf_spin_lock(false);

	if (test__start_subtest("tracing_deny"))

		test_tracing_deny();

}

tools/testing/selftests/bpf/progs/tracing_failure.c

+6 −0
Original line number Diff line number Diff line
@@ -18,3 +18,9 @@ int BPF_PROG(test_spin_unlock, struct bpf_spin_lock *lock) 
{

	return 0;

}



SEC("?fentry/__rcu_read_lock")

int BPF_PROG(tracing_deny)

{

	return 0;

}