1// SPDX-License-Identifier: GPL-2.0
  2#include <test_progs.h>
  3#include "kprobe_multi.skel.h"
  4#include "trace_helpers.h"
  5#include "kprobe_multi_empty.skel.h"
  6#include "kprobe_multi_override.skel.h"
  7#include "bpf/libbpf_internal.h"
  8#include "bpf/hashmap.h"
  9
 10static void kprobe_multi_test_run(struct kprobe_multi *skel, bool test_return)
 11{
 12	LIBBPF_OPTS(bpf_test_run_opts, topts);
 13	int err, prog_fd;
 14
 15	prog_fd = bpf_program__fd(skel->progs.trigger);
 16	err = bpf_prog_test_run_opts(prog_fd, &topts);
 17	ASSERT_OK(err, "test_run");
 18	ASSERT_EQ(topts.retval, 0, "test_run");
 19
 20	ASSERT_EQ(skel->bss->kprobe_test1_result, 1, "kprobe_test1_result");
 21	ASSERT_EQ(skel->bss->kprobe_test2_result, 1, "kprobe_test2_result");
 22	ASSERT_EQ(skel->bss->kprobe_test3_result, 1, "kprobe_test3_result");
 23	ASSERT_EQ(skel->bss->kprobe_test4_result, 1, "kprobe_test4_result");
 24	ASSERT_EQ(skel->bss->kprobe_test5_result, 1, "kprobe_test5_result");
 25	ASSERT_EQ(skel->bss->kprobe_test6_result, 1, "kprobe_test6_result");
 26	ASSERT_EQ(skel->bss->kprobe_test7_result, 1, "kprobe_test7_result");
 27	ASSERT_EQ(skel->bss->kprobe_test8_result, 1, "kprobe_test8_result");
 28
 29	if (test_return) {
 30		ASSERT_EQ(skel->bss->kretprobe_test1_result, 1, "kretprobe_test1_result");
 31		ASSERT_EQ(skel->bss->kretprobe_test2_result, 1, "kretprobe_test2_result");
 32		ASSERT_EQ(skel->bss->kretprobe_test3_result, 1, "kretprobe_test3_result");
 33		ASSERT_EQ(skel->bss->kretprobe_test4_result, 1, "kretprobe_test4_result");
 34		ASSERT_EQ(skel->bss->kretprobe_test5_result, 1, "kretprobe_test5_result");
 35		ASSERT_EQ(skel->bss->kretprobe_test6_result, 1, "kretprobe_test6_result");
 36		ASSERT_EQ(skel->bss->kretprobe_test7_result, 1, "kretprobe_test7_result");
 37		ASSERT_EQ(skel->bss->kretprobe_test8_result, 1, "kretprobe_test8_result");
 38	}
 39}
 40
 41static void test_skel_api(void)
 42{
 43	struct kprobe_multi *skel = NULL;
 44	int err;
 45
 46	skel = kprobe_multi__open_and_load();
 47	if (!ASSERT_OK_PTR(skel, "kprobe_multi__open_and_load"))
 48		goto cleanup;
 49
 50	skel->bss->pid = getpid();
 51	err = kprobe_multi__attach(skel);
 52	if (!ASSERT_OK(err, "kprobe_multi__attach"))
 53		goto cleanup;
 54
 55	kprobe_multi_test_run(skel, true);
 56
 57cleanup:
 58	kprobe_multi__destroy(skel);
 59}
 60
 61static void test_link_api(struct bpf_link_create_opts *opts)
 62{
 63	int prog_fd, link1_fd = -1, link2_fd = -1;
 64	struct kprobe_multi *skel = NULL;
 65
 66	skel = kprobe_multi__open_and_load();
 67	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
 68		goto cleanup;
 69
 70	skel->bss->pid = getpid();
 71	prog_fd = bpf_program__fd(skel->progs.test_kprobe);
 72	link1_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, opts);
 73	if (!ASSERT_GE(link1_fd, 0, "link_fd"))
 74		goto cleanup;
 75
 76	opts->kprobe_multi.flags = BPF_F_KPROBE_MULTI_RETURN;
 77	prog_fd = bpf_program__fd(skel->progs.test_kretprobe);
 78	link2_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_KPROBE_MULTI, opts);
 79	if (!ASSERT_GE(link2_fd, 0, "link_fd"))
 80		goto cleanup;
 81
 82	kprobe_multi_test_run(skel, true);
 83
 84cleanup:
 85	if (link1_fd != -1)
 86		close(link1_fd);
 87	if (link2_fd != -1)
 88		close(link2_fd);
 89	kprobe_multi__destroy(skel);
 90}
 91
 92#define GET_ADDR(__sym, __addr) ({					\
 93	__addr = ksym_get_addr(__sym);					\
 94	if (!ASSERT_NEQ(__addr, 0, "kallsyms load failed for " #__sym))	\
 95		return;							\
 96})
 97
 98static void test_link_api_addrs(void)
 99{
100	LIBBPF_OPTS(bpf_link_create_opts, opts);
101	unsigned long long addrs[8];
102
103	GET_ADDR("bpf_fentry_test1", addrs[0]);
104	GET_ADDR("bpf_fentry_test2", addrs[1]);
105	GET_ADDR("bpf_fentry_test3", addrs[2]);
106	GET_ADDR("bpf_fentry_test4", addrs[3]);
107	GET_ADDR("bpf_fentry_test5", addrs[4]);
108	GET_ADDR("bpf_fentry_test6", addrs[5]);
109	GET_ADDR("bpf_fentry_test7", addrs[6]);
110	GET_ADDR("bpf_fentry_test8", addrs[7]);
111
112	opts.kprobe_multi.addrs = (const unsigned long*) addrs;
113	opts.kprobe_multi.cnt = ARRAY_SIZE(addrs);
114	test_link_api(&opts);
115}
116
117static void test_link_api_syms(void)
118{
119	LIBBPF_OPTS(bpf_link_create_opts, opts);
120	const char *syms[8] = {
121		"bpf_fentry_test1",
122		"bpf_fentry_test2",
123		"bpf_fentry_test3",
124		"bpf_fentry_test4",
125		"bpf_fentry_test5",
126		"bpf_fentry_test6",
127		"bpf_fentry_test7",
128		"bpf_fentry_test8",
129	};
130
131	opts.kprobe_multi.syms = syms;
132	opts.kprobe_multi.cnt = ARRAY_SIZE(syms);
133	test_link_api(&opts);
134}
135
136static void
137test_attach_api(const char *pattern, struct bpf_kprobe_multi_opts *opts)
138{
139	struct bpf_link *link1 = NULL, *link2 = NULL;
140	struct kprobe_multi *skel = NULL;
141
142	skel = kprobe_multi__open_and_load();
143	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
144		goto cleanup;
145
146	skel->bss->pid = getpid();
147	link1 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
148						      pattern, opts);
149	if (!ASSERT_OK_PTR(link1, "bpf_program__attach_kprobe_multi_opts"))
150		goto cleanup;
151
152	if (opts) {
153		opts->retprobe = true;
154		link2 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kretprobe_manual,
155							      pattern, opts);
156		if (!ASSERT_OK_PTR(link2, "bpf_program__attach_kprobe_multi_opts"))
157			goto cleanup;
158	}
159
160	kprobe_multi_test_run(skel, !!opts);
161
162cleanup:
163	bpf_link__destroy(link2);
164	bpf_link__destroy(link1);
165	kprobe_multi__destroy(skel);
166}
167
168static void test_attach_api_pattern(void)
169{
170	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
171
172	test_attach_api("bpf_fentry_test*", &opts);
173	test_attach_api("bpf_fentry_test?", NULL);
174}
175
176static void test_attach_api_addrs(void)
177{
178	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
179	unsigned long long addrs[8];
180
181	GET_ADDR("bpf_fentry_test1", addrs[0]);
182	GET_ADDR("bpf_fentry_test2", addrs[1]);
183	GET_ADDR("bpf_fentry_test3", addrs[2]);
184	GET_ADDR("bpf_fentry_test4", addrs[3]);
185	GET_ADDR("bpf_fentry_test5", addrs[4]);
186	GET_ADDR("bpf_fentry_test6", addrs[5]);
187	GET_ADDR("bpf_fentry_test7", addrs[6]);
188	GET_ADDR("bpf_fentry_test8", addrs[7]);
189
190	opts.addrs = (const unsigned long *) addrs;
191	opts.cnt = ARRAY_SIZE(addrs);
192	test_attach_api(NULL, &opts);
193}
194
195static void test_attach_api_syms(void)
196{
197	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
198	const char *syms[8] = {
199		"bpf_fentry_test1",
200		"bpf_fentry_test2",
201		"bpf_fentry_test3",
202		"bpf_fentry_test4",
203		"bpf_fentry_test5",
204		"bpf_fentry_test6",
205		"bpf_fentry_test7",
206		"bpf_fentry_test8",
207	};
208
209	opts.syms = syms;
210	opts.cnt = ARRAY_SIZE(syms);
211	test_attach_api(NULL, &opts);
212}
213
214static void test_attach_api_fails(void)
215{
216	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
217	struct kprobe_multi *skel = NULL;
218	struct bpf_link *link = NULL;
219	unsigned long long addrs[2];
220	const char *syms[2] = {
221		"bpf_fentry_test1",
222		"bpf_fentry_test2",
223	};
224	__u64 cookies[2];
225	int saved_error;
226
227	addrs[0] = ksym_get_addr("bpf_fentry_test1");
228	addrs[1] = ksym_get_addr("bpf_fentry_test2");
229
230	if (!ASSERT_FALSE(!addrs[0] || !addrs[1], "ksym_get_addr"))
231		goto cleanup;
232
233	skel = kprobe_multi__open_and_load();
234	if (!ASSERT_OK_PTR(skel, "fentry_raw_skel_load"))
235		goto cleanup;
236
237	skel->bss->pid = getpid();
238
239	/* fail_1 - pattern and opts NULL */
240	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
241						     NULL, NULL);
242	saved_error = -errno;
243	if (!ASSERT_ERR_PTR(link, "fail_1"))
244		goto cleanup;
245
246	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_1_error"))
247		goto cleanup;
248
249	/* fail_2 - both addrs and syms set */
250	opts.addrs = (const unsigned long *) addrs;
251	opts.syms = syms;
252	opts.cnt = ARRAY_SIZE(syms);
253	opts.cookies = NULL;
254
255	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
256						     NULL, &opts);
257	saved_error = -errno;
258	if (!ASSERT_ERR_PTR(link, "fail_2"))
259		goto cleanup;
260
261	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_2_error"))
262		goto cleanup;
263
264	/* fail_3 - pattern and addrs set */
265	opts.addrs = (const unsigned long *) addrs;
266	opts.syms = NULL;
267	opts.cnt = ARRAY_SIZE(syms);
268	opts.cookies = NULL;
269
270	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
271						     "ksys_*", &opts);
272	saved_error = -errno;
273	if (!ASSERT_ERR_PTR(link, "fail_3"))
274		goto cleanup;
275
276	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_3_error"))
277		goto cleanup;
278
279	/* fail_4 - pattern and cnt set */
280	opts.addrs = NULL;
281	opts.syms = NULL;
282	opts.cnt = ARRAY_SIZE(syms);
283	opts.cookies = NULL;
284
285	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
286						     "ksys_*", &opts);
287	saved_error = -errno;
288	if (!ASSERT_ERR_PTR(link, "fail_4"))
289		goto cleanup;
290
291	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_4_error"))
292		goto cleanup;
293
294	/* fail_5 - pattern and cookies */
295	opts.addrs = NULL;
296	opts.syms = NULL;
297	opts.cnt = 0;
298	opts.cookies = cookies;
299
300	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
301						     "ksys_*", &opts);
302	saved_error = -errno;
303	if (!ASSERT_ERR_PTR(link, "fail_5"))
304		goto cleanup;
305
306	if (!ASSERT_EQ(saved_error, -EINVAL, "fail_5_error"))
307		goto cleanup;
308
309	/* fail_6 - abnormal cnt */
310	opts.addrs = (const unsigned long *) addrs;
311	opts.syms = NULL;
312	opts.cnt = INT_MAX;
313	opts.cookies = NULL;
314
315	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual,
316						     NULL, &opts);
317	saved_error = -errno;
318	if (!ASSERT_ERR_PTR(link, "fail_6"))
319		goto cleanup;
320
321	if (!ASSERT_EQ(saved_error, -E2BIG, "fail_6_error"))
322		goto cleanup;
323
324cleanup:
325	bpf_link__destroy(link);
326	kprobe_multi__destroy(skel);
327}
328
329static size_t symbol_hash(long key, void *ctx __maybe_unused)
330{
331	return str_hash((const char *) key);
332}
333
334static bool symbol_equal(long key1, long key2, void *ctx __maybe_unused)
335{
336	return strcmp((const char *) key1, (const char *) key2) == 0;
337}
338
339static int get_syms(char ***symsp, size_t *cntp, bool kernel)
340{
341	size_t cap = 0, cnt = 0, i;
342	char *name = NULL, **syms = NULL;
343	struct hashmap *map;
344	char buf[256];
345	FILE *f;
346	int err = 0;
347
348	/*
349	 * The available_filter_functions contains many duplicates,
350	 * but other than that all symbols are usable in kprobe multi
351	 * interface.
352	 * Filtering out duplicates by using hashmap__add, which won't
353	 * add existing entry.
354	 */
355
356	if (access("/sys/kernel/tracing/trace", F_OK) == 0)
357		f = fopen("/sys/kernel/tracing/available_filter_functions", "r");
358	else
359		f = fopen("/sys/kernel/debug/tracing/available_filter_functions", "r");
360
361	if (!f)
362		return -EINVAL;
363
364	map = hashmap__new(symbol_hash, symbol_equal, NULL);
365	if (IS_ERR(map)) {
366		err = libbpf_get_error(map);
367		goto error;
368	}
369
370	while (fgets(buf, sizeof(buf), f)) {
371		if (kernel && strchr(buf, '['))
372			continue;
373		if (!kernel && !strchr(buf, '['))
374			continue;
375
376		free(name);
377		if (sscanf(buf, "%ms$*[^\n]\n", &name) != 1)
378			continue;
379		/*
380		 * We attach to almost all kernel functions and some of them
381		 * will cause 'suspicious RCU usage' when fprobe is attached
382		 * to them. Filter out the current culprits - arch_cpu_idle
383		 * default_idle and rcu_* functions.
384		 */
385		if (!strcmp(name, "arch_cpu_idle"))
386			continue;
387		if (!strcmp(name, "default_idle"))
388			continue;
389		if (!strncmp(name, "rcu_", 4))
390			continue;
391		if (!strcmp(name, "bpf_dispatcher_xdp_func"))
392			continue;
393		if (!strncmp(name, "__ftrace_invalid_address__",
394			     sizeof("__ftrace_invalid_address__") - 1))
395			continue;
396
397		err = hashmap__add(map, name, 0);
398		if (err == -EEXIST) {
399			err = 0;
400			continue;
401		}
402		if (err)
403			goto error;
404
405		err = libbpf_ensure_mem((void **) &syms, &cap,
406					sizeof(*syms), cnt + 1);
407		if (err)
408			goto error;
409
410		syms[cnt++] = name;
411		name = NULL;
412	}
413
414	*symsp = syms;
415	*cntp = cnt;
416
417error:
418	free(name);
419	fclose(f);
420	hashmap__free(map);
421	if (err) {
422		for (i = 0; i < cnt; i++)
423			free(syms[i]);
424		free(syms);
425	}
426	return err;
427}
428
429static void test_kprobe_multi_bench_attach(bool kernel)
430{
431	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
432	struct kprobe_multi_empty *skel = NULL;
433	long attach_start_ns, attach_end_ns;
434	long detach_start_ns, detach_end_ns;
435	double attach_delta, detach_delta;
436	struct bpf_link *link = NULL;
437	char **syms = NULL;
438	size_t cnt = 0, i;
439
440	if (!ASSERT_OK(get_syms(&syms, &cnt, kernel), "get_syms"))
441		return;
442
443	skel = kprobe_multi_empty__open_and_load();
444	if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load"))
445		goto cleanup;
446
447	opts.syms = (const char **) syms;
448	opts.cnt = cnt;
449
450	attach_start_ns = get_time_ns();
451	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_empty,
452						     NULL, &opts);
453	attach_end_ns = get_time_ns();
454
455	if (!ASSERT_OK_PTR(link, "bpf_program__attach_kprobe_multi_opts"))
456		goto cleanup;
457
458	detach_start_ns = get_time_ns();
459	bpf_link__destroy(link);
460	detach_end_ns = get_time_ns();
461
462	attach_delta = (attach_end_ns - attach_start_ns) / 1000000000.0;
463	detach_delta = (detach_end_ns - detach_start_ns) / 1000000000.0;
464
465	printf("%s: found %lu functions\n", __func__, cnt);
466	printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
467	printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
468
469cleanup:
470	kprobe_multi_empty__destroy(skel);
471	if (syms) {
472		for (i = 0; i < cnt; i++)
473			free(syms[i]);
474		free(syms);
475	}
476}
477
478static void test_attach_override(void)
479{
480	struct kprobe_multi_override *skel = NULL;
481	struct bpf_link *link = NULL;
482
483	skel = kprobe_multi_override__open_and_load();
484	if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load"))
485		goto cleanup;
486
487	/* The test_override calls bpf_override_return so it should fail
488	 * to attach to bpf_fentry_test1 function, which is not on error
489	 * injection list.
490	 */
491	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_override,
492						     "bpf_fentry_test1", NULL);
493	if (!ASSERT_ERR_PTR(link, "override_attached_bpf_fentry_test1")) {
494		bpf_link__destroy(link);
495		goto cleanup;
496	}
497
498	/* The should_fail_bio function is on error injection list,
499	 * attach should succeed.
500	 */
501	link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_override,
502						     "should_fail_bio", NULL);
503	if (!ASSERT_OK_PTR(link, "override_attached_should_fail_bio"))
504		goto cleanup;
505
506	bpf_link__destroy(link);
507
508cleanup:
509	kprobe_multi_override__destroy(skel);
510}
511
512void serial_test_kprobe_multi_bench_attach(void)
513{
514	if (test__start_subtest("kernel"))
515		test_kprobe_multi_bench_attach(true);
516	if (test__start_subtest("modules"))
517		test_kprobe_multi_bench_attach(false);
518}
519
520void test_kprobe_multi_test(void)
521{
522	if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
523		return;
524
525	if (test__start_subtest("skel_api"))
526		test_skel_api();
527	if (test__start_subtest("link_api_addrs"))
528		test_link_api_syms();
529	if (test__start_subtest("link_api_syms"))
530		test_link_api_addrs();
531	if (test__start_subtest("attach_api_pattern"))
532		test_attach_api_pattern();
533	if (test__start_subtest("attach_api_addrs"))
534		test_attach_api_addrs();
535	if (test__start_subtest("attach_api_syms"))
536		test_attach_api_syms();
537	if (test__start_subtest("attach_api_fails"))
538		test_attach_api_fails();
539	if (test__start_subtest("attach_override"))
540		test_attach_override();
541}