selftests/bpf: Make sure bpf_{g,s}et_retval is exposed everywhere

For each hook, have a simple bpf_set_retval(bpf_get_retval) program
and make sure it loads for the hooks we want. The exceptions are
the hooks which don't propagate the error to the callers:

- sockops
- recvmsg
- getpeername
- getsockname
- cg_skb ingress and egress

Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220823222555.523590-6-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 48 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_getset_retval.c b/tools/testing/selftests/bpf/prog_tests/cgroup_getset_retval.c
index 0b47c3c000c7..4d2fa99273d8 100644
--- a/tools/testing/selftests/bpf/prog_tests/cgroup_getset_retval.c
+++ b/tools/testing/selftests/bpf/prog_tests/cgroup_getset_retval.c
@@ -10,6 +10,7 @@
 
 #include "cgroup_getset_retval_setsockopt.skel.h"
 #include "cgroup_getset_retval_getsockopt.skel.h"
+#include "cgroup_getset_retval_hooks.skel.h"
 
 #define SOL_CUSTOM	0xdeadbeef
 
@@ -433,6 +434,50 @@ close_bpf_object:
 	cgroup_getset_retval_getsockopt__destroy(obj);
 }
 
+struct exposed_hook {
+	const char *name;
+	int expected_err;
+} exposed_hooks[] = {
+
+#define BPF_RETVAL_HOOK(NAME, SECTION, CTX, EXPECTED_ERR) \
+	{ \
+		.name = #NAME, \
+		.expected_err = EXPECTED_ERR, \
+	},
+
+#include "cgroup_getset_retval_hooks.h"
+
+#undef BPF_RETVAL_HOOK
+};
+
+static void test_exposed_hooks(int cgroup_fd, int sock_fd)
+{
+	struct cgroup_getset_retval_hooks *skel;
+	struct bpf_program *prog;
+	int err;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(exposed_hooks); i++) {
+		skel = cgroup_getset_retval_hooks__open();
+		if (!ASSERT_OK_PTR(skel, "cgroup_getset_retval_hooks__open"))
+			continue;
+
+		prog = bpf_object__find_program_by_name(skel->obj, exposed_hooks[i].name);
+		if (!ASSERT_NEQ(prog, NULL, "bpf_object__find_program_by_name"))
+			goto close_skel;
+
+		err = bpf_program__set_autoload(prog, true);
+		if (!ASSERT_OK(err, "bpf_program__set_autoload"))
+			goto close_skel;
+
+		err = cgroup_getset_retval_hooks__load(skel);
+		ASSERT_EQ(err, exposed_hooks[i].expected_err, "expected_err");
+
+close_skel:
+		cgroup_getset_retval_hooks__destroy(skel);
+	}
+}
+
 void test_cgroup_getset_retval(void)
 {
 	int cgroup_fd = -1;
@@ -476,6 +521,9 @@ void test_cgroup_getset_retval(void)
 	if (test__start_subtest("getsockopt-retval_sync"))
 		test_getsockopt_retval_sync(cgroup_fd, sock_fd);
 
+	if (test__start_subtest("exposed_hooks"))
+		test_exposed_hooks(cgroup_fd, sock_fd);
+
 close_fd:
 	close(cgroup_fd);
 }