1 files changed, 541 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c
new file mode 100644
index 000000000000..05000810e28e
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c
@@ -0,0 +1,541 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <test_progs.h>
+#include "kprobe_multi.skel.h"
+#include "trace_helpers.h"
+#include "kprobe_multi_empty.skel.h"
+#include "kprobe_multi_override.skel.h"
+#include "bpf/libbpf_internal.h"
+#include "bpf/hashmap.h"
+
+static void kprobe_multi_test_run(struct kprobe_multi *skel, bool test_return)
+{
+	LIBBPF_OPTS(bpf_test_run_opts, topts);
+	int err, prog_fd;
+
+	prog_fd = bpf_program__fd(skel->progs.trigger);
+	err = bpf_prog_test_run_opts(prog_fd, &topts);
+	ASSERT_OK(err, "test_run");
+	ASSERT_EQ(topts.retval, 0, "test_run");
+
+	ASSERT_EQ(skel->bss->kprobe_test1_result, 1, "kprobe_test1_result");
+	ASSERT_EQ(skel->bss->kprobe_test2_result, 1, "kprobe_test2_result");
+	ASSERT_EQ(skel->bss->kprobe_test3_result, 1, "kprobe_test3_result");
+	ASSERT_EQ(skel->bss->kprobe_test4_result, 1, "kprobe_test4_result");
+	ASSERT_EQ(skel->bss->kprobe_test5_result, 1, "kprobe_test5_result");
+	ASSERT_EQ(skel->bss->kprobe_test6_result, 1, "kprobe_test6_result");
+	ASSERT_EQ(skel->bss->kprobe_test7_result, 1, "kprobe_test7_result");
+	ASSERT_EQ(skel->bss->kprobe_test8_result, 1, "kprobe_test8_result");
+
+	if (test_return) {
+		ASSERT_EQ(skel->bss->kretprobe_test1_result, 1, "kretprobe_test1_result");
+		ASSERT_EQ(skel->bss->kretprobe_test2_result, 1, "kretprobe_test2_result");
+		ASSERT_EQ(skel->bss->kretprobe_test3_result, 1, "kretprobe_test3_result");
+		ASSERT_EQ(skel->bss->kretprobe_test4_result, 1, "kretprobe_test4_result");
+		ASSERT_EQ(skel->bss->kretprobe_test5_result, 1, "kretprobe_test5_result");
+		ASSERT_EQ(skel->bss->kretprobe_test6_result, 1, "kretprobe_test6_result");
+		ASSERT_EQ(skel->bss->kretprobe_test7_result, 1, "kretprobe_test7_result");
+		ASSERT_EQ(skel->bss->kretprobe_test8_result, 1, "kretprobe_test8_result");
+	}
+}
+
+static void test_skel_api(void)
+{
+	struct kprobe_multi *skel = NULL;
+	int err;
+
+	skel = kprobe_multi__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "kprobe_multi__open_and_load"))
+		goto cleanup;
+
+	skel->bss->pid = getpid();
+	err = kprobe_multi__attach(skel);
+	if (!ASSERT_OK(err, "kprobe_multi__attach"))
+		goto cleanup;
+
+	kprobe_multi_test_run(skel, true);
+
+cleanup:
+	kprobe_multi__destroy(skel);
+}
+
+static void test_link_api(struct bpf_link_create_opts *opts)
+{
+	int prog_fd, link1_fd = -1, link2_fd = -1;
+	struct kprobe_multi *skel = NULL;
+
+	skel = kprobe_multi__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
+		goto cleanup;
+
+	skel->bss->pid = getpid();
+	prog_fd = bpf_program__fd(skel->progs.test_kprobe);
+	link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, opts);
+	if (!ASSERT_GE(link1_fd, 0, "link_fd"))
+		goto cleanup;
+
+	opts->kprobe_multi.flags = BPF_F_KPROBE_MULTI_RETURN;
+	prog_fd = bpf_program__fd(skel->progs.test_kretprobe);
+	link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, opts);
+	if (!ASSERT_GE(link2_fd, 0, "link_fd"))
+		goto cleanup;
+
+	kprobe_multi_test_run(skel, true);
+
+cleanup:
+	if (link1_fd != -1)
+		close(link1_fd);
+	if (link2_fd != -1)
+		close(link2_fd);
+	kprobe_multi__destroy(skel);
+}
+
+#define GET_ADDR(__sym, __addr) ({					\
+	__addr = ksym_get_addr(__sym);					\
+	if (!ASSERT_NEQ(__addr, 0, "kallsyms load failed for " #__sym))	\
+		return;							\
+})
+
+static void test_link_api_addrs(void)
+{
+	LIBBPF_OPTS(bpf_link_create_opts, opts);
+	unsigned long long addrs[8];
+
+	GET_ADDR("bpf_fentry_test1", addrs[0]);
+	GET_ADDR("bpf_fentry_test2", addrs[1]);
+	GET_ADDR("bpf_fentry_test3", addrs[2]);
+	GET_ADDR("bpf_fentry_test4", addrs[3]);
+	GET_ADDR("bpf_fentry_test5", addrs[4]);
+	GET_ADDR("bpf_fentry_test6", addrs[5]);
+	GET_ADDR("bpf_fentry_test7", addrs[6]);
+	GET_ADDR("bpf_fentry_test8", addrs[7]);
+
+	opts.kprobe_multi.addrs = (const unsigned long*) addrs;
+	opts.kprobe_multi.cnt = ARRAY_SIZE(addrs);
+	test_link_api(&opts);
+}
+
+static void test_link_api_syms(void)
+{
+	LIBBPF_OPTS(bpf_link_create_opts, opts);
+	const char *syms[8] = {
+		"bpf_fentry_test1",
+		"bpf_fentry_test2",
+		"bpf_fentry_test3",
+		"bpf_fentry_test4",
+		"bpf_fentry_test5",
+		"bpf_fentry_test6",
+		"bpf_fentry_test7",
+		"bpf_fentry_test8",
+	};
+
+	opts.kprobe_multi.syms = syms;
+	opts.kprobe_multi.cnt = ARRAY_SIZE(syms);
+	test_link_api(&opts);
+}
+
+static void
+test_attach_api(const char *pattern, struct bpf_kprobe_multi_opts *opts)
+{
+	struct bpf_link *link1 = NULL, *link2 = NULL;
+	struct kprobe_multi *skel = NULL;
+
+	skel = kprobe_multi__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
+		goto cleanup;
+
+	skel->bss->pid = getpid();
+	link1 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						      pattern, opts);
+	if (!ASSERT_OK_PTR(link1, "bpf_program__attach_kprobe_multi_opts"))
+		goto cleanup;
+
+	if (opts) {
+		opts->retprobe = true;
+		link2 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kretprobe_manual,
+							      pattern, opts);
+		if (!ASSERT_OK_PTR(link2, "bpf_program__attach_kprobe_multi_opts"))
+			goto cleanup;
+	}
+
+	kprobe_multi_test_run(skel, !!opts);
+
+cleanup:
+	bpf_link__destroy(link2);
+	bpf_link__destroy(link1);
+	kprobe_multi__destroy(skel);
+}
+
+static void test_attach_api_pattern(void)
+{
+	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+
+	test_attach_api("bpf_fentry_test*", &opts);
+	test_attach_api("bpf_fentry_test?", NULL);
+}
+
+static void test_attach_api_addrs(void)
+{
+	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+	unsigned long long addrs[8];
+
+	GET_ADDR("bpf_fentry_test1", addrs[0]);
+	GET_ADDR("bpf_fentry_test2", addrs[1]);
+	GET_ADDR("bpf_fentry_test3", addrs[2]);
+	GET_ADDR("bpf_fentry_test4", addrs[3]);
+	GET_ADDR("bpf_fentry_test5", addrs[4]);
+	GET_ADDR("bpf_fentry_test6", addrs[5]);
+	GET_ADDR("bpf_fentry_test7", addrs[6]);
+	GET_ADDR("bpf_fentry_test8", addrs[7]);
+
+	opts.addrs = (const unsigned long *) addrs;
+	opts.cnt = ARRAY_SIZE(addrs);
+	test_attach_api(NULL, &opts);
+}
+
+static void test_attach_api_syms(void)
+{
+	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+	const char *syms[8] = {
+		"bpf_fentry_test1",
+		"bpf_fentry_test2",
+		"bpf_fentry_test3",
+		"bpf_fentry_test4",
+		"bpf_fentry_test5",
+		"bpf_fentry_test6",
+		"bpf_fentry_test7",
+		"bpf_fentry_test8",
+	};
+
+	opts.syms = syms;
+	opts.cnt = ARRAY_SIZE(syms);
+	test_attach_api(NULL, &opts);
+}
+
+static void test_attach_api_fails(void)
+{
+	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+	struct kprobe_multi *skel = NULL;
+	struct bpf_link *link = NULL;
+	unsigned long long addrs[2];
+	const char *syms[2] = {
+		"bpf_fentry_test1",
+		"bpf_fentry_test2",
+	};
+	__u64 cookies[2];
+	int saved_error;
+
+	addrs[0] = ksym_get_addr("bpf_fentry_test1");
+	addrs[1] = ksym_get_addr("bpf_fentry_test2");
+
+	if (!ASSERT_FALSE(!addrs[0] || !addrs[1], "ksym_get_addr"))
+		goto cleanup;
+
+	skel = kprobe_multi__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
+		goto cleanup;
+
+	skel->bss->pid = getpid();
+
+	/* fail_1 - pattern and opts NULL */
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     NULL, NULL);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_1"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_1_error"))
+		goto cleanup;
+
+	/* fail_2 - both addrs and syms set */
+	opts.addrs = (const unsigned long *) addrs;
+	opts.syms = syms;
+	opts.cnt = ARRAY_SIZE(syms);
+	opts.cookies = NULL;
+
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     NULL, &opts);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_2"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_2_error"))
+		goto cleanup;
+
+	/* fail_3 - pattern and addrs set */
+	opts.addrs = (const unsigned long *) addrs;
+	opts.syms = NULL;
+	opts.cnt = ARRAY_SIZE(syms);
+	opts.cookies = NULL;
+
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     "ksys_*", &opts);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_3"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_3_error"))
+		goto cleanup;
+
+	/* fail_4 - pattern and cnt set */
+	opts.addrs = NULL;
+	opts.syms = NULL;
+	opts.cnt = ARRAY_SIZE(syms);
+	opts.cookies = NULL;
+
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     "ksys_*", &opts);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_4"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_4_error"))
+		goto cleanup;
+
+	/* fail_5 - pattern and cookies */
+	opts.addrs = NULL;
+	opts.syms = NULL;
+	opts.cnt = 0;
+	opts.cookies = cookies;
+
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     "ksys_*", &opts);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_5"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_5_error"))
+		goto cleanup;
+
+	/* fail_6 - abnormal cnt */
+	opts.addrs = (const unsigned long *) addrs;
+	opts.syms = NULL;
+	opts.cnt = INT_MAX;
+	opts.cookies = NULL;
+
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
+						     NULL, &opts);
+	saved_error = -errno;
+	if (!ASSERT_ERR_PTR(link, "fail_6"))
+		goto cleanup;
+
+	if (!ASSERT_EQ(saved_error, -E2BIG, "fail_6_error"))
+		goto cleanup;
+
+cleanup:
+	bpf_link__destroy(link);
+	kprobe_multi__destroy(skel);
+}
+
+static size_t symbol_hash(long key, void *ctx __maybe_unused)
+{
+	return str_hash((const char *) key);
+}
+
+static bool symbol_equal(long key1, long key2, void *ctx __maybe_unused)
+{
+	return strcmp((const char *) key1, (const char *) key2) == 0;
+}
+
+static int get_syms(char ***symsp, size_t *cntp, bool kernel)
+{
+	size_t cap = 0, cnt = 0, i;
+	char *name = NULL, **syms = NULL;
+	struct hashmap *map;
+	char buf[256];
+	FILE *f;
+	int err = 0;
+
+	/*
+	 * The available_filter_functions contains many duplicates,
+	 * but other than that all symbols are usable in kprobe multi
+	 * interface.
+	 * Filtering out duplicates by using hashmap__add, which won't
+	 * add existing entry.
+	 */
+
+	if (access("/sys/kernel/tracing/trace", F_OK) == 0)
+		f = fopen("/sys/kernel/tracing/available_filter_functions", "r");
+	else
+		f = fopen("/sys/kernel/debug/tracing/available_filter_functions", "r");
+
+	if (!f)
+		return -EINVAL;
+
+	map = hashmap__new(symbol_hash, symbol_equal, NULL);
+	if (IS_ERR(map)) {
+		err = libbpf_get_error(map);
+		goto error;
+	}
+
+	while (fgets(buf, sizeof(buf), f)) {
+		if (kernel && strchr(buf, '['))
+			continue;
+		if (!kernel && !strchr(buf, '['))
+			continue;
+
+		free(name);
+		if (sscanf(buf, "%ms$*[^\n]\n", &name) != 1)
+			continue;
+		/*
+		 * We attach to almost all kernel functions and some of them
+		 * will cause 'suspicious RCU usage' when fprobe is attached
+		 * to them. Filter out the current culprits - arch_cpu_idle
+		 * default_idle and rcu_* functions.
+		 */
+		if (!strcmp(name, "arch_cpu_idle"))
+			continue;
+		if (!strcmp(name, "default_idle"))
+			continue;
+		if (!strncmp(name, "rcu_", 4))
+			continue;
+		if (!strcmp(name, "bpf_dispatcher_xdp_func"))
+			continue;
+		if (!strncmp(name, "__ftrace_invalid_address__",
+			     sizeof("__ftrace_invalid_address__") - 1))
+			continue;
+
+		err = hashmap__add(map, name, 0);
+		if (err == -EEXIST) {
+			err = 0;
+			continue;
+		}
+		if (err)
+			goto error;
+
+		err = libbpf_ensure_mem((void **) &syms, &cap,
+					sizeof(*syms), cnt + 1);
+		if (err)
+			goto error;
+
+		syms[cnt++] = name;
+		name = NULL;
+	}
+
+	*symsp = syms;
+	*cntp = cnt;
+
+error:
+	free(name);
+	fclose(f);
+	hashmap__free(map);
+	if (err) {
+		for (i = 0; i < cnt; i++)
+			free(syms[i]);
+		free(syms);
+	}
+	return err;
+}
+
+static void test_kprobe_multi_bench_attach(bool kernel)
+{
+	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
+	struct kprobe_multi_empty *skel = NULL;
+	long attach_start_ns, attach_end_ns;
+	long detach_start_ns, detach_end_ns;
+	double attach_delta, detach_delta;
+	struct bpf_link *link = NULL;
+	char **syms = NULL;
+	size_t cnt = 0, i;
+
+	if (!ASSERT_OK(get_syms(&syms, &cnt, kernel), "get_syms"))
+		return;
+
+	skel = kprobe_multi_empty__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load"))
+		goto cleanup;
+
+	opts.syms = (const char **) syms;
+	opts.cnt = cnt;
+
+	attach_start_ns = get_time_ns();
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_empty,
+						     NULL, &opts);
+	attach_end_ns = get_time_ns();
+
+	if (!ASSERT_OK_PTR(link, "bpf_program__attach_kprobe_multi_opts"))
+		goto cleanup;
+
+	detach_start_ns = get_time_ns();
+	bpf_link__destroy(link);
+	detach_end_ns = get_time_ns();
+
+	attach_delta = (attach_end_ns - attach_start_ns) / 1000000000.0;
+	detach_delta = (detach_end_ns - detach_start_ns) / 1000000000.0;
+
+	printf("%s: found %lu functions\n", __func__, cnt);
+	printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
+	printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
+
+cleanup:
+	kprobe_multi_empty__destroy(skel);
+	if (syms) {
+		for (i = 0; i < cnt; i++)
+			free(syms[i]);
+		free(syms);
+	}
+}
+
+static void test_attach_override(void)
+{
+	struct kprobe_multi_override *skel = NULL;
+	struct bpf_link *link = NULL;
+
+	skel = kprobe_multi_override__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load"))
+		goto cleanup;
+
+	/* The test_override calls bpf_override_return so it should fail
+	 * to attach to bpf_fentry_test1 function, which is not on error
+	 * injection list.
+	 */
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_override,
+						     "bpf_fentry_test1", NULL);
+	if (!ASSERT_ERR_PTR(link, "override_attached_bpf_fentry_test1")) {
+		bpf_link__destroy(link);
+		goto cleanup;
+	}
+
+	/* The should_fail_bio function is on error injection list,
+	 * attach should succeed.
+	 */
+	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_override,
+						     "should_fail_bio", NULL);
+	if (!ASSERT_OK_PTR(link, "override_attached_should_fail_bio"))
+		goto cleanup;
+
+	bpf_link__destroy(link);
+
+cleanup:
+	kprobe_multi_override__destroy(skel);
+}
+
+void serial_test_kprobe_multi_bench_attach(void)
+{
+	if (test__start_subtest("kernel"))
+		test_kprobe_multi_bench_attach(true);
+	if (test__start_subtest("modules"))
+		test_kprobe_multi_bench_attach(false);
+}
+
+void test_kprobe_multi_test(void)
+{
+	if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
+		return;
+
+	if (test__start_subtest("skel_api"))
+		test_skel_api();
+	if (test__start_subtest("link_api_addrs"))
+		test_link_api_syms();
+	if (test__start_subtest("link_api_syms"))
+		test_link_api_addrs();
+	if (test__start_subtest("attach_api_pattern"))
+		test_attach_api_pattern();
+	if (test__start_subtest("attach_api_addrs"))
+		test_attach_api_addrs();
+	if (test__start_subtest("attach_api_syms"))
+		test_attach_api_syms();
+	if (test__start_subtest("attach_api_fails"))
+		test_attach_api_fails();
+	if (test__start_subtest("attach_override"))
+		test_attach_override();
+}