selftests/bpf: Add tests for restricted helpers

This patch adds tests that bpf_ktime_get_coarse_ns(), bpf_timer_* and
bpf_spin_lock()/bpf_spin_unlock() helpers are forbidden in tracing progs
as their use there may result in various locking issues.

Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211113142227.566439-3-me@ubique.spb.ru

1 files changed, 33 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/helper_restricted.c b/tools/testing/selftests/bpf/prog_tests/helper_restricted.c
new file mode 100644
index 000000000000..e1de5f80c3b2
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/helper_restricted.c
@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+#include "test_helper_restricted.skel.h"
+
+void test_helper_restricted(void)
+{
+	int prog_i = 0, prog_cnt;
+	int duration = 0;
+
+	do {
+		struct test_helper_restricted *test;
+		int maybeOK;
+
+		test = test_helper_restricted__open();
+		if (!ASSERT_OK_PTR(test, "open"))
+			return;
+
+		prog_cnt = test->skeleton->prog_cnt;
+
+		for (int j = 0; j < prog_cnt; ++j) {
+			struct bpf_program *prog = *test->skeleton->progs[j].prog;
+
+			maybeOK = bpf_program__set_autoload(prog, prog_i == j);
+			ASSERT_OK(maybeOK, "set autoload");
+		}
+
+		maybeOK = test_helper_restricted__load(test);
+		CHECK(!maybeOK, test->skeleton->progs[prog_i].name, "helper isn't restricted");
+
+		test_helper_restricted__destroy(test);
+	} while (++prog_i < prog_cnt);
+}