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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (C) 2023 Yafang Shao <laoar.shao@gmail.com> */
  3
  4#include <string.h>
  5#include <linux/bpf.h>
  6#include <linux/limits.h>
  7#include <test_progs.h>
  8#include "trace_helpers.h"
  9#include "test_fill_link_info.skel.h"
 10#include "bpf/libbpf_internal.h"
 11
 12#define TP_CAT "sched"
 13#define TP_NAME "sched_switch"
 14
 15static const char *kmulti_syms[] = {
 16	"bpf_fentry_test2",
 17	"bpf_fentry_test1",
 18	"bpf_fentry_test3",
 19};
 20#define KMULTI_CNT ARRAY_SIZE(kmulti_syms)
 21static __u64 kmulti_addrs[KMULTI_CNT];
 22static __u64 kmulti_cookies[] = { 3, 1, 2 };
 23
 24#define KPROBE_FUNC "bpf_fentry_test1"
 25static __u64 kprobe_addr;
 26
 27#define UPROBE_FILE "/proc/self/exe"
 28static ssize_t uprobe_offset;
 29/* uprobe attach point */
 30static noinline void uprobe_func(void)
 31{
 32	asm volatile ("");
 33}
 34
 35#define PERF_EVENT_COOKIE 0xdeadbeef
 36
 37static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr,
 38				 ssize_t offset, ssize_t entry_offset)
 39{
 40	struct bpf_link_info info;
 41	__u32 len = sizeof(info);
 42	char buf[PATH_MAX];
 43	int err;
 44
 45	memset(&info, 0, sizeof(info));
 46	buf[0] = '\0';
 47
 48again:
 49	err = bpf_link_get_info_by_fd(fd, &info, &len);
 50	if (!ASSERT_OK(err, "get_link_info"))
 51		return -1;
 52
 53	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_PERF_EVENT, "link_type"))
 54		return -1;
 55	if (!ASSERT_EQ(info.perf_event.type, type, "perf_type_match"))
 56		return -1;
 57
 58	switch (info.perf_event.type) {
 59	case BPF_PERF_EVENT_KPROBE:
 60	case BPF_PERF_EVENT_KRETPROBE:
 61		ASSERT_EQ(info.perf_event.kprobe.offset, offset, "kprobe_offset");
 62
 63		/* In case kernel.kptr_restrict is not permitted or MAX_SYMS is reached */
 64		if (addr)
 65			ASSERT_EQ(info.perf_event.kprobe.addr, addr + entry_offset,
 66				  "kprobe_addr");
 67
 68		ASSERT_EQ(info.perf_event.kprobe.cookie, PERF_EVENT_COOKIE, "kprobe_cookie");
 69
 70		ASSERT_EQ(info.perf_event.kprobe.name_len, strlen(KPROBE_FUNC) + 1,
 71				  "name_len");
 72		if (!info.perf_event.kprobe.func_name) {
 
 73			info.perf_event.kprobe.func_name = ptr_to_u64(&buf);
 74			info.perf_event.kprobe.name_len = sizeof(buf);
 75			goto again;
 76		}
 77
 78		err = strncmp(u64_to_ptr(info.perf_event.kprobe.func_name), KPROBE_FUNC,
 79			      strlen(KPROBE_FUNC));
 80		ASSERT_EQ(err, 0, "cmp_kprobe_func_name");
 81		break;
 82	case BPF_PERF_EVENT_TRACEPOINT:
 83		ASSERT_EQ(info.perf_event.tracepoint.name_len, strlen(TP_NAME) + 1,
 84				  "name_len");
 85		if (!info.perf_event.tracepoint.tp_name) {
 
 86			info.perf_event.tracepoint.tp_name = ptr_to_u64(&buf);
 87			info.perf_event.tracepoint.name_len = sizeof(buf);
 88			goto again;
 89		}
 90
 91		ASSERT_EQ(info.perf_event.tracepoint.cookie, PERF_EVENT_COOKIE, "tracepoint_cookie");
 92
 93		err = strncmp(u64_to_ptr(info.perf_event.tracepoint.tp_name), TP_NAME,
 94			      strlen(TP_NAME));
 95		ASSERT_EQ(err, 0, "cmp_tp_name");
 96		break;
 97	case BPF_PERF_EVENT_UPROBE:
 98	case BPF_PERF_EVENT_URETPROBE:
 99		ASSERT_EQ(info.perf_event.uprobe.offset, offset, "uprobe_offset");
100
101		ASSERT_EQ(info.perf_event.uprobe.name_len, strlen(UPROBE_FILE) + 1,
102				  "name_len");
103		if (!info.perf_event.uprobe.file_name) {
 
104			info.perf_event.uprobe.file_name = ptr_to_u64(&buf);
105			info.perf_event.uprobe.name_len = sizeof(buf);
106			goto again;
107		}
108
109		ASSERT_EQ(info.perf_event.uprobe.cookie, PERF_EVENT_COOKIE, "uprobe_cookie");
110
111		err = strncmp(u64_to_ptr(info.perf_event.uprobe.file_name), UPROBE_FILE,
112			      strlen(UPROBE_FILE));
113			ASSERT_EQ(err, 0, "cmp_file_name");
114		break;
115	case BPF_PERF_EVENT_EVENT:
116		ASSERT_EQ(info.perf_event.event.type, PERF_TYPE_SOFTWARE, "event_type");
117		ASSERT_EQ(info.perf_event.event.config, PERF_COUNT_SW_PAGE_FAULTS, "event_config");
118		ASSERT_EQ(info.perf_event.event.cookie, PERF_EVENT_COOKIE, "event_cookie");
119		break;
120	default:
121		err = -1;
122		break;
123	}
124	return err;
125}
126
127static void kprobe_fill_invalid_user_buffer(int fd)
128{
129	struct bpf_link_info info;
130	__u32 len = sizeof(info);
131	int err;
132
133	memset(&info, 0, sizeof(info));
134
135	info.perf_event.kprobe.func_name = 0x1; /* invalid address */
136	err = bpf_link_get_info_by_fd(fd, &info, &len);
137	ASSERT_EQ(err, -EINVAL, "invalid_buff_and_len");
138
139	info.perf_event.kprobe.name_len = 64;
140	err = bpf_link_get_info_by_fd(fd, &info, &len);
141	ASSERT_EQ(err, -EFAULT, "invalid_buff");
142
143	info.perf_event.kprobe.func_name = 0;
144	err = bpf_link_get_info_by_fd(fd, &info, &len);
145	ASSERT_EQ(err, -EINVAL, "invalid_len");
146
147	ASSERT_EQ(info.perf_event.kprobe.addr, 0, "func_addr");
148	ASSERT_EQ(info.perf_event.kprobe.offset, 0, "func_offset");
149	ASSERT_EQ(info.perf_event.type, 0, "type");
150}
151
152static void test_kprobe_fill_link_info(struct test_fill_link_info *skel,
153				       enum bpf_perf_event_type type,
154				       bool invalid)
155{
156	DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts,
157		.attach_mode = PROBE_ATTACH_MODE_LINK,
158		.retprobe = type == BPF_PERF_EVENT_KRETPROBE,
159		.bpf_cookie = PERF_EVENT_COOKIE,
160	);
161	ssize_t entry_offset = 0;
162	struct bpf_link *link;
163	int link_fd, err;
164
165	link = bpf_program__attach_kprobe_opts(skel->progs.kprobe_run, KPROBE_FUNC, &opts);
166	if (!ASSERT_OK_PTR(link, "attach_kprobe"))
167		return;
168
169	link_fd = bpf_link__fd(link);
170	if (!invalid) {
171		/* See also arch_adjust_kprobe_addr(). */
172		if (skel->kconfig->CONFIG_X86_KERNEL_IBT)
173			entry_offset = 4;
174		if (skel->kconfig->CONFIG_PPC64 &&
175		    skel->kconfig->CONFIG_KPROBES_ON_FTRACE &&
176		    !skel->kconfig->CONFIG_PPC_FTRACE_OUT_OF_LINE)
177			entry_offset = 4;
178		err = verify_perf_link_info(link_fd, type, kprobe_addr, 0, entry_offset);
179		ASSERT_OK(err, "verify_perf_link_info");
180	} else {
181		kprobe_fill_invalid_user_buffer(link_fd);
182	}
183	bpf_link__destroy(link);
184}
185
186static void test_tp_fill_link_info(struct test_fill_link_info *skel)
187{
188	DECLARE_LIBBPF_OPTS(bpf_tracepoint_opts, opts,
189		.bpf_cookie = PERF_EVENT_COOKIE,
190	);
191	struct bpf_link *link;
192	int link_fd, err;
193
194	link = bpf_program__attach_tracepoint_opts(skel->progs.tp_run, TP_CAT, TP_NAME, &opts);
195	if (!ASSERT_OK_PTR(link, "attach_tp"))
196		return;
197
198	link_fd = bpf_link__fd(link);
199	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_TRACEPOINT, 0, 0, 0);
200	ASSERT_OK(err, "verify_perf_link_info");
201	bpf_link__destroy(link);
202}
203
204static void test_event_fill_link_info(struct test_fill_link_info *skel)
205{
206	DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, opts,
207		.bpf_cookie = PERF_EVENT_COOKIE,
208	);
209	struct bpf_link *link;
210	int link_fd, err, pfd;
211	struct perf_event_attr attr = {
212		.type = PERF_TYPE_SOFTWARE,
213		.config = PERF_COUNT_SW_PAGE_FAULTS,
214		.freq = 1,
215		.sample_freq = 1,
216		.size = sizeof(struct perf_event_attr),
217	};
218
219	pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu 0 */,
220		      -1 /* group id */, 0 /* flags */);
221	if (!ASSERT_GE(pfd, 0, "perf_event_open"))
222		return;
223
224	link = bpf_program__attach_perf_event_opts(skel->progs.event_run, pfd, &opts);
225	if (!ASSERT_OK_PTR(link, "attach_event"))
226		goto error;
227
228	link_fd = bpf_link__fd(link);
229	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_EVENT, 0, 0, 0);
230	ASSERT_OK(err, "verify_perf_link_info");
231	bpf_link__destroy(link);
232
233error:
234	close(pfd);
235}
236
237static void test_uprobe_fill_link_info(struct test_fill_link_info *skel,
238				       enum bpf_perf_event_type type)
239{
240	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts,
241		.retprobe = type == BPF_PERF_EVENT_URETPROBE,
242		.bpf_cookie = PERF_EVENT_COOKIE,
243	);
244	struct bpf_link *link;
245	int link_fd, err;
246
247	link = bpf_program__attach_uprobe_opts(skel->progs.uprobe_run,
248					       0, /* self pid */
249					       UPROBE_FILE, uprobe_offset,
250					       &opts);
251	if (!ASSERT_OK_PTR(link, "attach_uprobe"))
252		return;
253
254	link_fd = bpf_link__fd(link);
255	err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0);
256	ASSERT_OK(err, "verify_perf_link_info");
257	bpf_link__destroy(link);
258}
259
260static int verify_kmulti_link_info(int fd, bool retprobe, bool has_cookies)
261{
262	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
263	struct bpf_link_info info;
264	__u32 len = sizeof(info);
265	int flags, i, err;
266
267	memset(&info, 0, sizeof(info));
268
269again:
270	err = bpf_link_get_info_by_fd(fd, &info, &len);
271	if (!ASSERT_OK(err, "get_link_info"))
272		return -1;
273
274	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_KPROBE_MULTI, "kmulti_type"))
275		return -1;
276
277	ASSERT_EQ(info.kprobe_multi.count, KMULTI_CNT, "func_cnt");
278	flags = info.kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN;
279	if (!retprobe)
280		ASSERT_EQ(flags, 0, "kmulti_flags");
281	else
282		ASSERT_NEQ(flags, 0, "kretmulti_flags");
283
284	if (!info.kprobe_multi.addrs) {
285		info.kprobe_multi.addrs = ptr_to_u64(addrs);
286		info.kprobe_multi.cookies = ptr_to_u64(cookies);
287		goto again;
288	}
289	for (i = 0; i < KMULTI_CNT; i++) {
290		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
291		ASSERT_EQ(cookies[i], has_cookies ? kmulti_cookies[i] : 0,
292			  "kmulti_cookies_value");
293	}
294	return 0;
295}
296
297static void verify_kmulti_invalid_user_buffer(int fd)
298{
299	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
300	struct bpf_link_info info;
301	__u32 len = sizeof(info);
302	int err, i;
303
304	memset(&info, 0, sizeof(info));
305
306	info.kprobe_multi.count = KMULTI_CNT;
307	err = bpf_link_get_info_by_fd(fd, &info, &len);
308	ASSERT_EQ(err, -EINVAL, "no_addr");
309
310	info.kprobe_multi.addrs = ptr_to_u64(addrs);
311	info.kprobe_multi.count = 0;
312	err = bpf_link_get_info_by_fd(fd, &info, &len);
313	ASSERT_EQ(err, -EINVAL, "no_cnt");
314
315	for (i = 0; i < KMULTI_CNT; i++)
316		addrs[i] = 0;
317	info.kprobe_multi.count = KMULTI_CNT - 1;
318	err = bpf_link_get_info_by_fd(fd, &info, &len);
319	ASSERT_EQ(err, -ENOSPC, "smaller_cnt");
320	for (i = 0; i < KMULTI_CNT - 1; i++)
321		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
322	ASSERT_EQ(addrs[i], 0, "kmulti_addrs");
323
324	for (i = 0; i < KMULTI_CNT; i++)
325		addrs[i] = 0;
326	info.kprobe_multi.count = KMULTI_CNT + 1;
327	err = bpf_link_get_info_by_fd(fd, &info, &len);
328	ASSERT_EQ(err, 0, "bigger_cnt");
329	for (i = 0; i < KMULTI_CNT; i++)
330		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
331
332	info.kprobe_multi.count = KMULTI_CNT;
333	info.kprobe_multi.addrs = 0x1; /* invalid addr */
334	err = bpf_link_get_info_by_fd(fd, &info, &len);
335	ASSERT_EQ(err, -EFAULT, "invalid_buff_addrs");
336
337	info.kprobe_multi.count = KMULTI_CNT;
338	info.kprobe_multi.addrs = ptr_to_u64(addrs);
339	info.kprobe_multi.cookies = 0x1; /* invalid addr */
340	err = bpf_link_get_info_by_fd(fd, &info, &len);
341	ASSERT_EQ(err, -EFAULT, "invalid_buff_cookies");
342
343	/* cookies && !count */
344	info.kprobe_multi.count = 0;
345	info.kprobe_multi.addrs = ptr_to_u64(NULL);
346	info.kprobe_multi.cookies = ptr_to_u64(cookies);
347	err = bpf_link_get_info_by_fd(fd, &info, &len);
348	ASSERT_EQ(err, -EINVAL, "invalid_cookies_count");
349}
350
351static int symbols_cmp_r(const void *a, const void *b)
352{
353	const char **str_a = (const char **) a;
354	const char **str_b = (const char **) b;
355
356	return strcmp(*str_a, *str_b);
357}
358
359static void test_kprobe_multi_fill_link_info(struct test_fill_link_info *skel,
360					     bool retprobe, bool cookies,
361					     bool invalid)
362{
363	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
364	struct bpf_link *link;
365	int link_fd, err;
366
367	opts.syms = kmulti_syms;
368	opts.cookies = cookies ? kmulti_cookies : NULL;
369	opts.cnt = KMULTI_CNT;
370	opts.retprobe = retprobe;
371	link = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run, NULL, &opts);
372	if (!ASSERT_OK_PTR(link, "attach_kprobe_multi"))
373		return;
374
375	link_fd = bpf_link__fd(link);
376	if (!invalid) {
377		err = verify_kmulti_link_info(link_fd, retprobe, cookies);
378		ASSERT_OK(err, "verify_kmulti_link_info");
379	} else {
380		verify_kmulti_invalid_user_buffer(link_fd);
381	}
382	bpf_link__destroy(link);
383}
384
385#define SEC(name) __attribute__((section(name), used))
386
387static short uprobe_link_info_sema_1 SEC(".probes");
388static short uprobe_link_info_sema_2 SEC(".probes");
389static short uprobe_link_info_sema_3 SEC(".probes");
390
391noinline void uprobe_link_info_func_1(void)
392{
393	asm volatile ("");
394	uprobe_link_info_sema_1++;
395}
396
397noinline void uprobe_link_info_func_2(void)
398{
399	asm volatile ("");
400	uprobe_link_info_sema_2++;
401}
402
403noinline void uprobe_link_info_func_3(void)
404{
405	asm volatile ("");
406	uprobe_link_info_sema_3++;
407}
408
409static int
410verify_umulti_link_info(int fd, bool retprobe, __u64 *offsets,
411			__u64 *cookies, __u64 *ref_ctr_offsets)
412{
413	char path[PATH_MAX], path_buf[PATH_MAX];
414	struct bpf_link_info info;
415	__u32 len = sizeof(info);
416	__u64 ref_ctr_offsets_buf[3];
417	__u64 offsets_buf[3];
418	__u64 cookies_buf[3];
419	int i, err, bit;
420	__u32 count = 0;
421
422	memset(path, 0, sizeof(path));
423	err = readlink("/proc/self/exe", path, sizeof(path));
424	if (!ASSERT_NEQ(err, -1, "readlink"))
425		return -1;
426
427	memset(&info, 0, sizeof(info));
428	err = bpf_link_get_info_by_fd(fd, &info, &len);
429	if (!ASSERT_OK(err, "bpf_link_get_info_by_fd"))
430		return -1;
431
432	ASSERT_EQ(info.uprobe_multi.count, 3, "info.uprobe_multi.count");
433	ASSERT_EQ(info.uprobe_multi.path_size, strlen(path) + 1,
434		  "info.uprobe_multi.path_size");
435
436	for (bit = 0; bit < 8; bit++) {
437		memset(&info, 0, sizeof(info));
438		info.uprobe_multi.path = ptr_to_u64(path_buf);
439		info.uprobe_multi.path_size = sizeof(path_buf);
440		info.uprobe_multi.count = count;
441
442		if (bit & 0x1)
443			info.uprobe_multi.offsets = ptr_to_u64(offsets_buf);
444		if (bit & 0x2)
445			info.uprobe_multi.cookies = ptr_to_u64(cookies_buf);
446		if (bit & 0x4)
447			info.uprobe_multi.ref_ctr_offsets = ptr_to_u64(ref_ctr_offsets_buf);
448
449		err = bpf_link_get_info_by_fd(fd, &info, &len);
450		if (!ASSERT_OK(err, "bpf_link_get_info_by_fd"))
451			return -1;
452
453		if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_UPROBE_MULTI, "info.type"))
454			return -1;
455
456		ASSERT_EQ(info.uprobe_multi.pid, getpid(), "info.uprobe_multi.pid");
457		ASSERT_EQ(info.uprobe_multi.count, 3, "info.uprobe_multi.count");
458		ASSERT_EQ(info.uprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN,
459			  retprobe, "info.uprobe_multi.flags.retprobe");
460		ASSERT_EQ(info.uprobe_multi.path_size, strlen(path) + 1, "info.uprobe_multi.path_size");
461		ASSERT_STREQ(path_buf, path, "info.uprobe_multi.path");
462
463		for (i = 0; i < info.uprobe_multi.count; i++) {
464			if (info.uprobe_multi.offsets)
465				ASSERT_EQ(offsets_buf[i], offsets[i], "info.uprobe_multi.offsets");
466			if (info.uprobe_multi.cookies)
467				ASSERT_EQ(cookies_buf[i], cookies[i], "info.uprobe_multi.cookies");
468			if (info.uprobe_multi.ref_ctr_offsets) {
469				ASSERT_EQ(ref_ctr_offsets_buf[i], ref_ctr_offsets[i],
470					  "info.uprobe_multi.ref_ctr_offsets");
471			}
472		}
473		count = count ?: info.uprobe_multi.count;
474	}
475
476	return 0;
477}
478
479static void verify_umulti_invalid_user_buffer(int fd)
480{
481	struct bpf_link_info info;
482	__u32 len = sizeof(info);
483	__u64 buf[3];
484	int err;
485
486	/* upath_size defined, not path */
487	memset(&info, 0, sizeof(info));
488	info.uprobe_multi.path_size = 3;
489	err = bpf_link_get_info_by_fd(fd, &info, &len);
490	ASSERT_EQ(err, -EINVAL, "failed_upath_size");
491
492	/* path defined, but small */
493	memset(&info, 0, sizeof(info));
494	info.uprobe_multi.path = ptr_to_u64(buf);
495	info.uprobe_multi.path_size = 3;
496	err = bpf_link_get_info_by_fd(fd, &info, &len);
497	ASSERT_LT(err, 0, "failed_upath_small");
498
499	/* path has wrong pointer */
500	memset(&info, 0, sizeof(info));
501	info.uprobe_multi.path_size = PATH_MAX;
502	info.uprobe_multi.path = 123;
503	err = bpf_link_get_info_by_fd(fd, &info, &len);
504	ASSERT_EQ(err, -EFAULT, "failed_bad_path_ptr");
505
506	/* count zero, with offsets */
507	memset(&info, 0, sizeof(info));
508	info.uprobe_multi.offsets = ptr_to_u64(buf);
509	err = bpf_link_get_info_by_fd(fd, &info, &len);
510	ASSERT_EQ(err, -EINVAL, "failed_count");
511
512	/* offsets not big enough */
513	memset(&info, 0, sizeof(info));
514	info.uprobe_multi.offsets = ptr_to_u64(buf);
515	info.uprobe_multi.count = 2;
516	err = bpf_link_get_info_by_fd(fd, &info, &len);
517	ASSERT_EQ(err, -ENOSPC, "failed_small_count");
518
519	/* offsets has wrong pointer */
520	memset(&info, 0, sizeof(info));
521	info.uprobe_multi.offsets = 123;
522	info.uprobe_multi.count = 3;
523	err = bpf_link_get_info_by_fd(fd, &info, &len);
524	ASSERT_EQ(err, -EFAULT, "failed_wrong_offsets");
525}
526
527static void test_uprobe_multi_fill_link_info(struct test_fill_link_info *skel,
528					     bool retprobe, bool invalid)
529{
530	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
531		.retprobe = retprobe,
532	);
533	const char *syms[3] = {
534		"uprobe_link_info_func_1",
535		"uprobe_link_info_func_2",
536		"uprobe_link_info_func_3",
537	};
538	__u64 cookies[3] = {
539		0xdead,
540		0xbeef,
541		0xcafe,
542	};
543	const char *sema[3] = {
544		"uprobe_link_info_sema_1",
545		"uprobe_link_info_sema_2",
546		"uprobe_link_info_sema_3",
547	};
548	__u64 *offsets = NULL, *ref_ctr_offsets;
549	struct bpf_link *link;
550	int link_fd, err;
551
552	err = elf_resolve_syms_offsets("/proc/self/exe", 3, sema,
553				       (unsigned long **) &ref_ctr_offsets, STT_OBJECT);
554	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_object"))
555		return;
556
557	err = elf_resolve_syms_offsets("/proc/self/exe", 3, syms,
558				       (unsigned long **) &offsets, STT_FUNC);
559	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_func"))
560		goto out;
561
562	opts.syms = syms;
563	opts.cookies = &cookies[0];
564	opts.ref_ctr_offsets = (unsigned long *) &ref_ctr_offsets[0];
565	opts.cnt = ARRAY_SIZE(syms);
566
567	link = bpf_program__attach_uprobe_multi(skel->progs.umulti_run, 0,
568						"/proc/self/exe", NULL, &opts);
569	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
570		goto out;
571
572	link_fd = bpf_link__fd(link);
573	if (invalid)
574		verify_umulti_invalid_user_buffer(link_fd);
575	else
576		verify_umulti_link_info(link_fd, retprobe, offsets, cookies, ref_ctr_offsets);
577
578	bpf_link__destroy(link);
579out:
580	free(ref_ctr_offsets);
581	free(offsets);
582}
583
584void test_fill_link_info(void)
585{
586	struct test_fill_link_info *skel;
587	int i;
588
589	skel = test_fill_link_info__open_and_load();
590	if (!ASSERT_OK_PTR(skel, "skel_open"))
591		return;
592
593	/* load kallsyms to compare the addr */
594	if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
595		goto cleanup;
596
597	kprobe_addr = ksym_get_addr(KPROBE_FUNC);
598	if (test__start_subtest("kprobe_link_info"))
599		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, false);
600	if (test__start_subtest("kretprobe_link_info"))
601		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KRETPROBE, false);
602	if (test__start_subtest("kprobe_invalid_ubuff"))
603		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, true);
604	if (test__start_subtest("tracepoint_link_info"))
605		test_tp_fill_link_info(skel);
606	if (test__start_subtest("event_link_info"))
607		test_event_fill_link_info(skel);
608
609	uprobe_offset = get_uprobe_offset(&uprobe_func);
610	if (test__start_subtest("uprobe_link_info"))
611		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_UPROBE);
612	if (test__start_subtest("uretprobe_link_info"))
613		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_URETPROBE);
614
615	qsort(kmulti_syms, KMULTI_CNT, sizeof(kmulti_syms[0]), symbols_cmp_r);
616	for (i = 0; i < KMULTI_CNT; i++)
617		kmulti_addrs[i] = ksym_get_addr(kmulti_syms[i]);
618	if (test__start_subtest("kprobe_multi_link_info")) {
619		test_kprobe_multi_fill_link_info(skel, false, false, false);
620		test_kprobe_multi_fill_link_info(skel, false, true, false);
621	}
622	if (test__start_subtest("kretprobe_multi_link_info")) {
623		test_kprobe_multi_fill_link_info(skel, true, false, false);
624		test_kprobe_multi_fill_link_info(skel, true, true, false);
625	}
626	if (test__start_subtest("kprobe_multi_invalid_ubuff"))
627		test_kprobe_multi_fill_link_info(skel, true, true, true);
628
629	if (test__start_subtest("uprobe_multi_link_info"))
630		test_uprobe_multi_fill_link_info(skel, false, false);
631	if (test__start_subtest("uretprobe_multi_link_info"))
632		test_uprobe_multi_fill_link_info(skel, true, false);
633	if (test__start_subtest("uprobe_multi_invalid"))
634		test_uprobe_multi_fill_link_info(skel, false, true);
635
636cleanup:
637	test_fill_link_info__destroy(skel);
638}
v6.9.4
  1// SPDX-License-Identifier: GPL-2.0
  2/* Copyright (C) 2023 Yafang Shao <laoar.shao@gmail.com> */
  3
  4#include <string.h>
  5#include <linux/bpf.h>
  6#include <linux/limits.h>
  7#include <test_progs.h>
  8#include "trace_helpers.h"
  9#include "test_fill_link_info.skel.h"
 10#include "bpf/libbpf_internal.h"
 11
 12#define TP_CAT "sched"
 13#define TP_NAME "sched_switch"
 14
 15static const char *kmulti_syms[] = {
 16	"bpf_fentry_test2",
 17	"bpf_fentry_test1",
 18	"bpf_fentry_test3",
 19};
 20#define KMULTI_CNT ARRAY_SIZE(kmulti_syms)
 21static __u64 kmulti_addrs[KMULTI_CNT];
 22static __u64 kmulti_cookies[] = { 3, 1, 2 };
 23
 24#define KPROBE_FUNC "bpf_fentry_test1"
 25static __u64 kprobe_addr;
 26
 27#define UPROBE_FILE "/proc/self/exe"
 28static ssize_t uprobe_offset;
 29/* uprobe attach point */
 30static noinline void uprobe_func(void)
 31{
 32	asm volatile ("");
 33}
 34
 35#define PERF_EVENT_COOKIE 0xdeadbeef
 36
 37static int verify_perf_link_info(int fd, enum bpf_perf_event_type type, long addr,
 38				 ssize_t offset, ssize_t entry_offset)
 39{
 40	struct bpf_link_info info;
 41	__u32 len = sizeof(info);
 42	char buf[PATH_MAX];
 43	int err;
 44
 45	memset(&info, 0, sizeof(info));
 46	buf[0] = '\0';
 47
 48again:
 49	err = bpf_link_get_info_by_fd(fd, &info, &len);
 50	if (!ASSERT_OK(err, "get_link_info"))
 51		return -1;
 52
 53	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_PERF_EVENT, "link_type"))
 54		return -1;
 55	if (!ASSERT_EQ(info.perf_event.type, type, "perf_type_match"))
 56		return -1;
 57
 58	switch (info.perf_event.type) {
 59	case BPF_PERF_EVENT_KPROBE:
 60	case BPF_PERF_EVENT_KRETPROBE:
 61		ASSERT_EQ(info.perf_event.kprobe.offset, offset, "kprobe_offset");
 62
 63		/* In case kernel.kptr_restrict is not permitted or MAX_SYMS is reached */
 64		if (addr)
 65			ASSERT_EQ(info.perf_event.kprobe.addr, addr + entry_offset,
 66				  "kprobe_addr");
 67
 68		ASSERT_EQ(info.perf_event.kprobe.cookie, PERF_EVENT_COOKIE, "kprobe_cookie");
 69
 
 
 70		if (!info.perf_event.kprobe.func_name) {
 71			ASSERT_EQ(info.perf_event.kprobe.name_len, 0, "name_len");
 72			info.perf_event.kprobe.func_name = ptr_to_u64(&buf);
 73			info.perf_event.kprobe.name_len = sizeof(buf);
 74			goto again;
 75		}
 76
 77		err = strncmp(u64_to_ptr(info.perf_event.kprobe.func_name), KPROBE_FUNC,
 78			      strlen(KPROBE_FUNC));
 79		ASSERT_EQ(err, 0, "cmp_kprobe_func_name");
 80		break;
 81	case BPF_PERF_EVENT_TRACEPOINT:
 
 
 82		if (!info.perf_event.tracepoint.tp_name) {
 83			ASSERT_EQ(info.perf_event.tracepoint.name_len, 0, "name_len");
 84			info.perf_event.tracepoint.tp_name = ptr_to_u64(&buf);
 85			info.perf_event.tracepoint.name_len = sizeof(buf);
 86			goto again;
 87		}
 88
 89		ASSERT_EQ(info.perf_event.tracepoint.cookie, PERF_EVENT_COOKIE, "tracepoint_cookie");
 90
 91		err = strncmp(u64_to_ptr(info.perf_event.tracepoint.tp_name), TP_NAME,
 92			      strlen(TP_NAME));
 93		ASSERT_EQ(err, 0, "cmp_tp_name");
 94		break;
 95	case BPF_PERF_EVENT_UPROBE:
 96	case BPF_PERF_EVENT_URETPROBE:
 97		ASSERT_EQ(info.perf_event.uprobe.offset, offset, "uprobe_offset");
 98
 
 
 99		if (!info.perf_event.uprobe.file_name) {
100			ASSERT_EQ(info.perf_event.uprobe.name_len, 0, "name_len");
101			info.perf_event.uprobe.file_name = ptr_to_u64(&buf);
102			info.perf_event.uprobe.name_len = sizeof(buf);
103			goto again;
104		}
105
106		ASSERT_EQ(info.perf_event.uprobe.cookie, PERF_EVENT_COOKIE, "uprobe_cookie");
107
108		err = strncmp(u64_to_ptr(info.perf_event.uprobe.file_name), UPROBE_FILE,
109			      strlen(UPROBE_FILE));
110			ASSERT_EQ(err, 0, "cmp_file_name");
111		break;
112	case BPF_PERF_EVENT_EVENT:
113		ASSERT_EQ(info.perf_event.event.type, PERF_TYPE_SOFTWARE, "event_type");
114		ASSERT_EQ(info.perf_event.event.config, PERF_COUNT_SW_PAGE_FAULTS, "event_config");
115		ASSERT_EQ(info.perf_event.event.cookie, PERF_EVENT_COOKIE, "event_cookie");
116		break;
117	default:
118		err = -1;
119		break;
120	}
121	return err;
122}
123
124static void kprobe_fill_invalid_user_buffer(int fd)
125{
126	struct bpf_link_info info;
127	__u32 len = sizeof(info);
128	int err;
129
130	memset(&info, 0, sizeof(info));
131
132	info.perf_event.kprobe.func_name = 0x1; /* invalid address */
133	err = bpf_link_get_info_by_fd(fd, &info, &len);
134	ASSERT_EQ(err, -EINVAL, "invalid_buff_and_len");
135
136	info.perf_event.kprobe.name_len = 64;
137	err = bpf_link_get_info_by_fd(fd, &info, &len);
138	ASSERT_EQ(err, -EFAULT, "invalid_buff");
139
140	info.perf_event.kprobe.func_name = 0;
141	err = bpf_link_get_info_by_fd(fd, &info, &len);
142	ASSERT_EQ(err, -EINVAL, "invalid_len");
143
144	ASSERT_EQ(info.perf_event.kprobe.addr, 0, "func_addr");
145	ASSERT_EQ(info.perf_event.kprobe.offset, 0, "func_offset");
146	ASSERT_EQ(info.perf_event.type, 0, "type");
147}
148
149static void test_kprobe_fill_link_info(struct test_fill_link_info *skel,
150				       enum bpf_perf_event_type type,
151				       bool invalid)
152{
153	DECLARE_LIBBPF_OPTS(bpf_kprobe_opts, opts,
154		.attach_mode = PROBE_ATTACH_MODE_LINK,
155		.retprobe = type == BPF_PERF_EVENT_KRETPROBE,
156		.bpf_cookie = PERF_EVENT_COOKIE,
157	);
158	ssize_t entry_offset = 0;
159	struct bpf_link *link;
160	int link_fd, err;
161
162	link = bpf_program__attach_kprobe_opts(skel->progs.kprobe_run, KPROBE_FUNC, &opts);
163	if (!ASSERT_OK_PTR(link, "attach_kprobe"))
164		return;
165
166	link_fd = bpf_link__fd(link);
167	if (!invalid) {
168		/* See also arch_adjust_kprobe_addr(). */
169		if (skel->kconfig->CONFIG_X86_KERNEL_IBT)
170			entry_offset = 4;
 
 
 
 
171		err = verify_perf_link_info(link_fd, type, kprobe_addr, 0, entry_offset);
172		ASSERT_OK(err, "verify_perf_link_info");
173	} else {
174		kprobe_fill_invalid_user_buffer(link_fd);
175	}
176	bpf_link__destroy(link);
177}
178
179static void test_tp_fill_link_info(struct test_fill_link_info *skel)
180{
181	DECLARE_LIBBPF_OPTS(bpf_tracepoint_opts, opts,
182		.bpf_cookie = PERF_EVENT_COOKIE,
183	);
184	struct bpf_link *link;
185	int link_fd, err;
186
187	link = bpf_program__attach_tracepoint_opts(skel->progs.tp_run, TP_CAT, TP_NAME, &opts);
188	if (!ASSERT_OK_PTR(link, "attach_tp"))
189		return;
190
191	link_fd = bpf_link__fd(link);
192	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_TRACEPOINT, 0, 0, 0);
193	ASSERT_OK(err, "verify_perf_link_info");
194	bpf_link__destroy(link);
195}
196
197static void test_event_fill_link_info(struct test_fill_link_info *skel)
198{
199	DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, opts,
200		.bpf_cookie = PERF_EVENT_COOKIE,
201	);
202	struct bpf_link *link;
203	int link_fd, err, pfd;
204	struct perf_event_attr attr = {
205		.type = PERF_TYPE_SOFTWARE,
206		.config = PERF_COUNT_SW_PAGE_FAULTS,
207		.freq = 1,
208		.sample_freq = 1,
209		.size = sizeof(struct perf_event_attr),
210	};
211
212	pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu 0 */,
213		      -1 /* group id */, 0 /* flags */);
214	if (!ASSERT_GE(pfd, 0, "perf_event_open"))
215		return;
216
217	link = bpf_program__attach_perf_event_opts(skel->progs.event_run, pfd, &opts);
218	if (!ASSERT_OK_PTR(link, "attach_event"))
219		goto error;
220
221	link_fd = bpf_link__fd(link);
222	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_EVENT, 0, 0, 0);
223	ASSERT_OK(err, "verify_perf_link_info");
224	bpf_link__destroy(link);
225
226error:
227	close(pfd);
228}
229
230static void test_uprobe_fill_link_info(struct test_fill_link_info *skel,
231				       enum bpf_perf_event_type type)
232{
233	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts,
234		.retprobe = type == BPF_PERF_EVENT_URETPROBE,
235		.bpf_cookie = PERF_EVENT_COOKIE,
236	);
237	struct bpf_link *link;
238	int link_fd, err;
239
240	link = bpf_program__attach_uprobe_opts(skel->progs.uprobe_run,
241					       0, /* self pid */
242					       UPROBE_FILE, uprobe_offset,
243					       &opts);
244	if (!ASSERT_OK_PTR(link, "attach_uprobe"))
245		return;
246
247	link_fd = bpf_link__fd(link);
248	err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0);
249	ASSERT_OK(err, "verify_perf_link_info");
250	bpf_link__destroy(link);
251}
252
253static int verify_kmulti_link_info(int fd, bool retprobe, bool has_cookies)
254{
255	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
256	struct bpf_link_info info;
257	__u32 len = sizeof(info);
258	int flags, i, err;
259
260	memset(&info, 0, sizeof(info));
261
262again:
263	err = bpf_link_get_info_by_fd(fd, &info, &len);
264	if (!ASSERT_OK(err, "get_link_info"))
265		return -1;
266
267	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_KPROBE_MULTI, "kmulti_type"))
268		return -1;
269
270	ASSERT_EQ(info.kprobe_multi.count, KMULTI_CNT, "func_cnt");
271	flags = info.kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN;
272	if (!retprobe)
273		ASSERT_EQ(flags, 0, "kmulti_flags");
274	else
275		ASSERT_NEQ(flags, 0, "kretmulti_flags");
276
277	if (!info.kprobe_multi.addrs) {
278		info.kprobe_multi.addrs = ptr_to_u64(addrs);
279		info.kprobe_multi.cookies = ptr_to_u64(cookies);
280		goto again;
281	}
282	for (i = 0; i < KMULTI_CNT; i++) {
283		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
284		ASSERT_EQ(cookies[i], has_cookies ? kmulti_cookies[i] : 0,
285			  "kmulti_cookies_value");
286	}
287	return 0;
288}
289
290static void verify_kmulti_invalid_user_buffer(int fd)
291{
292	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
293	struct bpf_link_info info;
294	__u32 len = sizeof(info);
295	int err, i;
296
297	memset(&info, 0, sizeof(info));
298
299	info.kprobe_multi.count = KMULTI_CNT;
300	err = bpf_link_get_info_by_fd(fd, &info, &len);
301	ASSERT_EQ(err, -EINVAL, "no_addr");
302
303	info.kprobe_multi.addrs = ptr_to_u64(addrs);
304	info.kprobe_multi.count = 0;
305	err = bpf_link_get_info_by_fd(fd, &info, &len);
306	ASSERT_EQ(err, -EINVAL, "no_cnt");
307
308	for (i = 0; i < KMULTI_CNT; i++)
309		addrs[i] = 0;
310	info.kprobe_multi.count = KMULTI_CNT - 1;
311	err = bpf_link_get_info_by_fd(fd, &info, &len);
312	ASSERT_EQ(err, -ENOSPC, "smaller_cnt");
313	for (i = 0; i < KMULTI_CNT - 1; i++)
314		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
315	ASSERT_EQ(addrs[i], 0, "kmulti_addrs");
316
317	for (i = 0; i < KMULTI_CNT; i++)
318		addrs[i] = 0;
319	info.kprobe_multi.count = KMULTI_CNT + 1;
320	err = bpf_link_get_info_by_fd(fd, &info, &len);
321	ASSERT_EQ(err, 0, "bigger_cnt");
322	for (i = 0; i < KMULTI_CNT; i++)
323		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
324
325	info.kprobe_multi.count = KMULTI_CNT;
326	info.kprobe_multi.addrs = 0x1; /* invalid addr */
327	err = bpf_link_get_info_by_fd(fd, &info, &len);
328	ASSERT_EQ(err, -EFAULT, "invalid_buff_addrs");
329
330	info.kprobe_multi.count = KMULTI_CNT;
331	info.kprobe_multi.addrs = ptr_to_u64(addrs);
332	info.kprobe_multi.cookies = 0x1; /* invalid addr */
333	err = bpf_link_get_info_by_fd(fd, &info, &len);
334	ASSERT_EQ(err, -EFAULT, "invalid_buff_cookies");
335
336	/* cookies && !count */
337	info.kprobe_multi.count = 0;
338	info.kprobe_multi.addrs = ptr_to_u64(NULL);
339	info.kprobe_multi.cookies = ptr_to_u64(cookies);
340	err = bpf_link_get_info_by_fd(fd, &info, &len);
341	ASSERT_EQ(err, -EINVAL, "invalid_cookies_count");
342}
343
344static int symbols_cmp_r(const void *a, const void *b)
345{
346	const char **str_a = (const char **) a;
347	const char **str_b = (const char **) b;
348
349	return strcmp(*str_a, *str_b);
350}
351
352static void test_kprobe_multi_fill_link_info(struct test_fill_link_info *skel,
353					     bool retprobe, bool cookies,
354					     bool invalid)
355{
356	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
357	struct bpf_link *link;
358	int link_fd, err;
359
360	opts.syms = kmulti_syms;
361	opts.cookies = cookies ? kmulti_cookies : NULL;
362	opts.cnt = KMULTI_CNT;
363	opts.retprobe = retprobe;
364	link = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run, NULL, &opts);
365	if (!ASSERT_OK_PTR(link, "attach_kprobe_multi"))
366		return;
367
368	link_fd = bpf_link__fd(link);
369	if (!invalid) {
370		err = verify_kmulti_link_info(link_fd, retprobe, cookies);
371		ASSERT_OK(err, "verify_kmulti_link_info");
372	} else {
373		verify_kmulti_invalid_user_buffer(link_fd);
374	}
375	bpf_link__destroy(link);
376}
377
378#define SEC(name) __attribute__((section(name), used))
379
380static short uprobe_link_info_sema_1 SEC(".probes");
381static short uprobe_link_info_sema_2 SEC(".probes");
382static short uprobe_link_info_sema_3 SEC(".probes");
383
384noinline void uprobe_link_info_func_1(void)
385{
386	asm volatile ("");
387	uprobe_link_info_sema_1++;
388}
389
390noinline void uprobe_link_info_func_2(void)
391{
392	asm volatile ("");
393	uprobe_link_info_sema_2++;
394}
395
396noinline void uprobe_link_info_func_3(void)
397{
398	asm volatile ("");
399	uprobe_link_info_sema_3++;
400}
401
402static int
403verify_umulti_link_info(int fd, bool retprobe, __u64 *offsets,
404			__u64 *cookies, __u64 *ref_ctr_offsets)
405{
406	char path[PATH_MAX], path_buf[PATH_MAX];
407	struct bpf_link_info info;
408	__u32 len = sizeof(info);
409	__u64 ref_ctr_offsets_buf[3];
410	__u64 offsets_buf[3];
411	__u64 cookies_buf[3];
412	int i, err, bit;
413	__u32 count = 0;
414
415	memset(path, 0, sizeof(path));
416	err = readlink("/proc/self/exe", path, sizeof(path));
417	if (!ASSERT_NEQ(err, -1, "readlink"))
418		return -1;
 
 
 
 
 
 
 
 
 
419
420	for (bit = 0; bit < 8; bit++) {
421		memset(&info, 0, sizeof(info));
422		info.uprobe_multi.path = ptr_to_u64(path_buf);
423		info.uprobe_multi.path_size = sizeof(path_buf);
424		info.uprobe_multi.count = count;
425
426		if (bit & 0x1)
427			info.uprobe_multi.offsets = ptr_to_u64(offsets_buf);
428		if (bit & 0x2)
429			info.uprobe_multi.cookies = ptr_to_u64(cookies_buf);
430		if (bit & 0x4)
431			info.uprobe_multi.ref_ctr_offsets = ptr_to_u64(ref_ctr_offsets_buf);
432
433		err = bpf_link_get_info_by_fd(fd, &info, &len);
434		if (!ASSERT_OK(err, "bpf_link_get_info_by_fd"))
435			return -1;
436
437		if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_UPROBE_MULTI, "info.type"))
438			return -1;
439
440		ASSERT_EQ(info.uprobe_multi.pid, getpid(), "info.uprobe_multi.pid");
441		ASSERT_EQ(info.uprobe_multi.count, 3, "info.uprobe_multi.count");
442		ASSERT_EQ(info.uprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN,
443			  retprobe, "info.uprobe_multi.flags.retprobe");
444		ASSERT_EQ(info.uprobe_multi.path_size, strlen(path) + 1, "info.uprobe_multi.path_size");
445		ASSERT_STREQ(path_buf, path, "info.uprobe_multi.path");
446
447		for (i = 0; i < info.uprobe_multi.count; i++) {
448			if (info.uprobe_multi.offsets)
449				ASSERT_EQ(offsets_buf[i], offsets[i], "info.uprobe_multi.offsets");
450			if (info.uprobe_multi.cookies)
451				ASSERT_EQ(cookies_buf[i], cookies[i], "info.uprobe_multi.cookies");
452			if (info.uprobe_multi.ref_ctr_offsets) {
453				ASSERT_EQ(ref_ctr_offsets_buf[i], ref_ctr_offsets[i],
454					  "info.uprobe_multi.ref_ctr_offsets");
455			}
456		}
457		count = count ?: info.uprobe_multi.count;
458	}
459
460	return 0;
461}
462
463static void verify_umulti_invalid_user_buffer(int fd)
464{
465	struct bpf_link_info info;
466	__u32 len = sizeof(info);
467	__u64 buf[3];
468	int err;
469
470	/* upath_size defined, not path */
471	memset(&info, 0, sizeof(info));
472	info.uprobe_multi.path_size = 3;
473	err = bpf_link_get_info_by_fd(fd, &info, &len);
474	ASSERT_EQ(err, -EINVAL, "failed_upath_size");
475
476	/* path defined, but small */
477	memset(&info, 0, sizeof(info));
478	info.uprobe_multi.path = ptr_to_u64(buf);
479	info.uprobe_multi.path_size = 3;
480	err = bpf_link_get_info_by_fd(fd, &info, &len);
481	ASSERT_LT(err, 0, "failed_upath_small");
482
483	/* path has wrong pointer */
484	memset(&info, 0, sizeof(info));
485	info.uprobe_multi.path_size = PATH_MAX;
486	info.uprobe_multi.path = 123;
487	err = bpf_link_get_info_by_fd(fd, &info, &len);
488	ASSERT_EQ(err, -EFAULT, "failed_bad_path_ptr");
489
490	/* count zero, with offsets */
491	memset(&info, 0, sizeof(info));
492	info.uprobe_multi.offsets = ptr_to_u64(buf);
493	err = bpf_link_get_info_by_fd(fd, &info, &len);
494	ASSERT_EQ(err, -EINVAL, "failed_count");
495
496	/* offsets not big enough */
497	memset(&info, 0, sizeof(info));
498	info.uprobe_multi.offsets = ptr_to_u64(buf);
499	info.uprobe_multi.count = 2;
500	err = bpf_link_get_info_by_fd(fd, &info, &len);
501	ASSERT_EQ(err, -ENOSPC, "failed_small_count");
502
503	/* offsets has wrong pointer */
504	memset(&info, 0, sizeof(info));
505	info.uprobe_multi.offsets = 123;
506	info.uprobe_multi.count = 3;
507	err = bpf_link_get_info_by_fd(fd, &info, &len);
508	ASSERT_EQ(err, -EFAULT, "failed_wrong_offsets");
509}
510
511static void test_uprobe_multi_fill_link_info(struct test_fill_link_info *skel,
512					     bool retprobe, bool invalid)
513{
514	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
515		.retprobe = retprobe,
516	);
517	const char *syms[3] = {
518		"uprobe_link_info_func_1",
519		"uprobe_link_info_func_2",
520		"uprobe_link_info_func_3",
521	};
522	__u64 cookies[3] = {
523		0xdead,
524		0xbeef,
525		0xcafe,
526	};
527	const char *sema[3] = {
528		"uprobe_link_info_sema_1",
529		"uprobe_link_info_sema_2",
530		"uprobe_link_info_sema_3",
531	};
532	__u64 *offsets = NULL, *ref_ctr_offsets;
533	struct bpf_link *link;
534	int link_fd, err;
535
536	err = elf_resolve_syms_offsets("/proc/self/exe", 3, sema,
537				       (unsigned long **) &ref_ctr_offsets, STT_OBJECT);
538	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_object"))
539		return;
540
541	err = elf_resolve_syms_offsets("/proc/self/exe", 3, syms,
542				       (unsigned long **) &offsets, STT_FUNC);
543	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_func"))
544		goto out;
545
546	opts.syms = syms;
547	opts.cookies = &cookies[0];
548	opts.ref_ctr_offsets = (unsigned long *) &ref_ctr_offsets[0];
549	opts.cnt = ARRAY_SIZE(syms);
550
551	link = bpf_program__attach_uprobe_multi(skel->progs.umulti_run, 0,
552						"/proc/self/exe", NULL, &opts);
553	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
554		goto out;
555
556	link_fd = bpf_link__fd(link);
557	if (invalid)
558		verify_umulti_invalid_user_buffer(link_fd);
559	else
560		verify_umulti_link_info(link_fd, retprobe, offsets, cookies, ref_ctr_offsets);
561
562	bpf_link__destroy(link);
563out:
564	free(ref_ctr_offsets);
565	free(offsets);
566}
567
568void test_fill_link_info(void)
569{
570	struct test_fill_link_info *skel;
571	int i;
572
573	skel = test_fill_link_info__open_and_load();
574	if (!ASSERT_OK_PTR(skel, "skel_open"))
575		return;
576
577	/* load kallsyms to compare the addr */
578	if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
579		goto cleanup;
580
581	kprobe_addr = ksym_get_addr(KPROBE_FUNC);
582	if (test__start_subtest("kprobe_link_info"))
583		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, false);
584	if (test__start_subtest("kretprobe_link_info"))
585		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KRETPROBE, false);
586	if (test__start_subtest("kprobe_invalid_ubuff"))
587		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, true);
588	if (test__start_subtest("tracepoint_link_info"))
589		test_tp_fill_link_info(skel);
590	if (test__start_subtest("event_link_info"))
591		test_event_fill_link_info(skel);
592
593	uprobe_offset = get_uprobe_offset(&uprobe_func);
594	if (test__start_subtest("uprobe_link_info"))
595		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_UPROBE);
596	if (test__start_subtest("uretprobe_link_info"))
597		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_URETPROBE);
598
599	qsort(kmulti_syms, KMULTI_CNT, sizeof(kmulti_syms[0]), symbols_cmp_r);
600	for (i = 0; i < KMULTI_CNT; i++)
601		kmulti_addrs[i] = ksym_get_addr(kmulti_syms[i]);
602	if (test__start_subtest("kprobe_multi_link_info")) {
603		test_kprobe_multi_fill_link_info(skel, false, false, false);
604		test_kprobe_multi_fill_link_info(skel, false, true, false);
605	}
606	if (test__start_subtest("kretprobe_multi_link_info")) {
607		test_kprobe_multi_fill_link_info(skel, true, false, false);
608		test_kprobe_multi_fill_link_info(skel, true, true, false);
609	}
610	if (test__start_subtest("kprobe_multi_invalid_ubuff"))
611		test_kprobe_multi_fill_link_info(skel, true, true, true);
612
613	if (test__start_subtest("uprobe_multi_link_info"))
614		test_uprobe_multi_fill_link_info(skel, false, false);
615	if (test__start_subtest("uretprobe_multi_link_info"))
616		test_uprobe_multi_fill_link_info(skel, true, false);
617	if (test__start_subtest("uprobe_multi_invalid"))
618		test_uprobe_multi_fill_link_info(skel, false, true);
619
620cleanup:
621	test_fill_link_info__destroy(skel);
622}