Subject: [PATCH 13/13] selftest/bpf: Add bpf_cookie test for raw_k[ret]probe

From: Jiri Olsa <[email-masked]>
Date: Tue, 4 Jan 2022 09:09:43 +0100

Adding bpf_cookie test for raw_k[ret]probes.

Using the bpf_link_create interface directly and single
trampoline program to trigger the bpf_fentry_test1
execution.

Signed-off-by: Jiri Olsa <[email-masked]>
---
 .../selftests/bpf/prog_tests/bpf_cookie.c     | 42 +++++++++++++++++++
 .../selftests/bpf/progs/test_bpf_cookie.c     | 24 ++++++++++-
 2 files changed, 65 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
index 5eea3c3a40fe..aee01dd3a823 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_cookie.c
@@ -57,6 +57,46 @@ static void kprobe_subtest(struct test_bpf_cookie *skel)
 	bpf_link__destroy(retlink2);
 }
 
+static void rawkprobe_subtest(struct test_bpf_cookie *skel)
+{
+	DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
+	int err, prog_fd, link1_fd = -1, link2_fd = -1;
+	__u32 duration = 0, retval;
+	__u64 addr;
+
+	kallsyms_find("bpf_fentry_test1", &addr);
+
+	opts.kprobe.addrs = (__u64) &addr;
+	opts.kprobe.cnt = 1;
+	opts.kprobe.bpf_cookie = 0x1;
+	prog_fd = bpf_program__fd(skel->progs.handle_raw_kprobe);
+
+	link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_RAW_KPROBE, &opts);
+	if (!ASSERT_GE(link1_fd, 0, "link1_fd"))
+		return;
+
+	opts.flags = BPF_F_KPROBE_RETURN;
+	opts.kprobe.bpf_cookie = 0x2;
+	prog_fd = bpf_program__fd(skel->progs.handle_raw_kretprobe);
+
+	link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_RAW_KPROBE, &opts);
+	if (!ASSERT_GE(link2_fd, 0, "link2_fd"))
+		goto cleanup;
+
+	prog_fd = bpf_program__fd(skel->progs.raw_trigger);
+	err = bpf_prog_test_run(prog_fd, 1, NULL, 0,
+				NULL, NULL, &retval, &duration);
+	ASSERT_OK(err, "test_run");
+	ASSERT_EQ(retval, 0, "test_run");
+
+	ASSERT_EQ(skel->bss->raw_kprobe_res, 0x1, "raw_kprobe_res");
+	ASSERT_EQ(skel->bss->raw_kretprobe_res, 0x2, "raw_kretprobe_res");
+
+cleanup:
+	close(link1_fd);
+	close(link2_fd);
+}
+
 static void uprobe_subtest(struct test_bpf_cookie *skel)
 {
 	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts);
@@ -243,6 +283,8 @@ void test_bpf_cookie(void)
 
 	if (test__start_subtest("kprobe"))
 		kprobe_subtest(skel);
+	if (test__start_subtest("rawkprobe"))
+		rawkprobe_subtest(skel);
 	if (test__start_subtest("uprobe"))
 		uprobe_subtest(skel);
 	if (test__start_subtest("tracepoint"))
diff --git a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c
index 2d3a7710e2ce..409f87464b1f 100644
--- a/tools/testing/selftests/bpf/progs/test_bpf_cookie.c
+++ b/tools/testing/selftests/bpf/progs/test_bpf_cookie.c
@@ -8,8 +8,9 @@
 int my_tid;
 
 int kprobe_res;
-int kprobe_multi_res;
 int kretprobe_res;
+int raw_kprobe_res;
+int raw_kretprobe_res;
 int uprobe_res;
 int uretprobe_res;
 int tp_res;
@@ -37,6 +38,27 @@ int handle_kretprobe(struct pt_regs *ctx)
 	return 0;
 }
 
+SEC("kprobe/bpf_fentry_test1")
+int handle_raw_kprobe(struct pt_regs *ctx)
+{
+	update(ctx, &raw_kprobe_res);
+	return 0;
+}
+
+SEC("kretprobe/bpf_fentry_test1")
+int handle_raw_kretprobe(struct pt_regs *ctx)
+{
+	update(ctx, &raw_kretprobe_res);
+	return 0;
+}
+
+/* just to trigger bpf_fentry_test1 through tracing test_run */
+SEC("fentry/bpf_modify_return_test")
+int BPF_PROG(raw_trigger)
+{
+	return 0;
+}
+
 SEC("uprobe/trigger_func")
 int handle_uprobe(struct pt_regs *ctx)
 {
-- 
2.33.1