selftests/bpf: Add test for raw-address single kprobe attach

Currently, attach_probe covers manual single-kprobe attaches by
func_name, but not the raw-address form that the PMU-based
single-kprobe path can accept.

This commit adds PERF and LINK raw-address coverage. It resolves
SYS_NANOSLEEP_KPROBE_NAME through kallsyms, passes the absolute address
in bpf_kprobe_opts.offset with func_name = NULL, and verifies that
kprobe and kretprobe are still triggered. It also verifies that LEGACY
rejects the same form.

Signed-off-by: Hoyeon Lee <hoyeon.lee@suse.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/20260401143116.185049-4-hoyeon.lee@suse.com

diff --git a/tools/testing/selftests/bpf/prog_tests/attach_probe.c b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
index 38852df70c0d2e358a9f9d34eec4f558e98ee365..12a841afda6860441ee161c9e1cb9e213f11ba1e 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/attach_probe.c
+++ b/tools/testing/selftests/bpf/prog_tests/attach_probe.c
@@ -123,6 +123,80 @@ cleanup:
        test_attach_probe_manual__destroy(skel);
 }
 
+/* manual attach address-based kprobe/kretprobe testings */
+static void test_attach_kprobe_by_addr(enum probe_attach_mode attach_mode)
+{
+       LIBBPF_OPTS(bpf_kprobe_opts, kprobe_opts);
+       struct test_attach_probe_manual *skel;
+       unsigned long func_addr;
+
+       if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
+               return;
+
+       func_addr = ksym_get_addr(SYS_NANOSLEEP_KPROBE_NAME);
+       if (!ASSERT_NEQ(func_addr, 0UL, "func_addr"))
+               return;
+
+       skel = test_attach_probe_manual__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "skel_kprobe_manual_open_and_load"))
+               return;
+
+       kprobe_opts.attach_mode = attach_mode;
+       kprobe_opts.retprobe = false;
+       kprobe_opts.offset = func_addr;
+       skel->links.handle_kprobe =
+               bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe,
+                                               NULL, &kprobe_opts);
+       if (!ASSERT_OK_PTR(skel->links.handle_kprobe, "attach_kprobe_by_addr"))
+               goto cleanup;
+
+       kprobe_opts.retprobe = true;
+       skel->links.handle_kretprobe =
+               bpf_program__attach_kprobe_opts(skel->progs.handle_kretprobe,
+                                               NULL, &kprobe_opts);
+       if (!ASSERT_OK_PTR(skel->links.handle_kretprobe, "attach_kretprobe_by_addr"))
+               goto cleanup;
+
+       /* trigger & validate kprobe && kretprobe */
+       usleep(1);
+
+       ASSERT_EQ(skel->bss->kprobe_res, 1, "check_kprobe_res");
+       ASSERT_EQ(skel->bss->kretprobe_res, 2, "check_kretprobe_res");
+
+cleanup:
+       test_attach_probe_manual__destroy(skel);
+}
+
+/* reject legacy address-based kprobe attach */
+static void test_attach_kprobe_legacy_by_addr_reject(void)
+{
+       LIBBPF_OPTS(bpf_kprobe_opts, kprobe_opts);
+       struct test_attach_probe_manual *skel;
+       unsigned long func_addr;
+
+       if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
+               return;
+
+       func_addr = ksym_get_addr(SYS_NANOSLEEP_KPROBE_NAME);
+       if (!ASSERT_NEQ(func_addr, 0UL, "func_addr"))
+               return;
+
+       skel = test_attach_probe_manual__open_and_load();
+       if (!ASSERT_OK_PTR(skel, "skel_kprobe_manual_open_and_load"))
+               return;
+
+       kprobe_opts.attach_mode = PROBE_ATTACH_MODE_LEGACY;
+       kprobe_opts.offset = func_addr;
+       skel->links.handle_kprobe =
+               bpf_program__attach_kprobe_opts(skel->progs.handle_kprobe,
+                                               NULL, &kprobe_opts);
+       ASSERT_ERR_PTR(skel->links.handle_kprobe, "attach_kprobe_legacy_by_addr");
+       ASSERT_EQ(libbpf_get_error(skel->links.handle_kprobe),
+                 -EOPNOTSUPP, "attach_kprobe_legacy_by_addr_err");
+
+       test_attach_probe_manual__destroy(skel);
+}
+
 /* attach uprobe/uretprobe long event name testings */
 static void test_attach_uprobe_long_event_name(void)
 {
@@ -478,6 +552,12 @@ void test_attach_probe(void)
                test_attach_probe_manual(PROBE_ATTACH_MODE_PERF);
        if (test__start_subtest("manual-link"))
                test_attach_probe_manual(PROBE_ATTACH_MODE_LINK);
+       if (test__start_subtest("kprobe-perf-by-addr"))
+               test_attach_kprobe_by_addr(PROBE_ATTACH_MODE_PERF);
+       if (test__start_subtest("kprobe-link-by-addr"))
+               test_attach_kprobe_by_addr(PROBE_ATTACH_MODE_LINK);
+       if (test__start_subtest("kprobe-legacy-by-addr-reject"))
+               test_attach_kprobe_legacy_by_addr_reject();
 
        if (test__start_subtest("auto"))
                test_attach_probe_auto(skel);