xref: /linux/tools/testing/selftests/bpf/prog_tests/fill_link_info.c (revision 3d5ad2d4eca337e80f38df77de89614aa5aaceb9)
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 
15 static 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)
21 static __u64 kmulti_addrs[KMULTI_CNT];
22 static __u64 kmulti_cookies[] = { 3, 1, 2 };
23 
24 #define KPROBE_FUNC "bpf_fentry_test1"
25 static __u64 kprobe_addr;
26 
27 #define UPROBE_FILE "/proc/self/exe"
28 static ssize_t uprobe_offset;
29 /* uprobe attach point */
uprobe_func(void)30 static noinline void uprobe_func(void)
31 {
32 	asm volatile ("");
33 }
34 
35 #define PERF_EVENT_COOKIE 0xdeadbeef
36 
verify_perf_link_info(int fd,enum bpf_perf_event_type type,long addr,ssize_t offset,ssize_t entry_offset)37 static 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 
48 again:
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 
kprobe_fill_invalid_user_buffer(int fd)127 static 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 
test_kprobe_fill_link_info(struct test_fill_link_info * skel,enum bpf_perf_event_type type,bool invalid)152 static 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 		err = verify_perf_link_info(link_fd, type, kprobe_addr, 0, entry_offset);
175 		ASSERT_OK(err, "verify_perf_link_info");
176 	} else {
177 		kprobe_fill_invalid_user_buffer(link_fd);
178 	}
179 	bpf_link__destroy(link);
180 }
181 
test_tp_fill_link_info(struct test_fill_link_info * skel)182 static void test_tp_fill_link_info(struct test_fill_link_info *skel)
183 {
184 	DECLARE_LIBBPF_OPTS(bpf_tracepoint_opts, opts,
185 		.bpf_cookie = PERF_EVENT_COOKIE,
186 	);
187 	struct bpf_link *link;
188 	int link_fd, err;
189 
190 	link = bpf_program__attach_tracepoint_opts(skel->progs.tp_run, TP_CAT, TP_NAME, &opts);
191 	if (!ASSERT_OK_PTR(link, "attach_tp"))
192 		return;
193 
194 	link_fd = bpf_link__fd(link);
195 	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_TRACEPOINT, 0, 0, 0);
196 	ASSERT_OK(err, "verify_perf_link_info");
197 	bpf_link__destroy(link);
198 }
199 
test_event_fill_link_info(struct test_fill_link_info * skel)200 static void test_event_fill_link_info(struct test_fill_link_info *skel)
201 {
202 	DECLARE_LIBBPF_OPTS(bpf_perf_event_opts, opts,
203 		.bpf_cookie = PERF_EVENT_COOKIE,
204 	);
205 	struct bpf_link *link;
206 	int link_fd, err, pfd;
207 	struct perf_event_attr attr = {
208 		.type = PERF_TYPE_SOFTWARE,
209 		.config = PERF_COUNT_SW_PAGE_FAULTS,
210 		.freq = 1,
211 		.sample_freq = 1,
212 		.size = sizeof(struct perf_event_attr),
213 	};
214 
215 	pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu 0 */,
216 		      -1 /* group id */, 0 /* flags */);
217 	if (!ASSERT_GE(pfd, 0, "perf_event_open"))
218 		return;
219 
220 	link = bpf_program__attach_perf_event_opts(skel->progs.event_run, pfd, &opts);
221 	if (!ASSERT_OK_PTR(link, "attach_event"))
222 		goto error;
223 
224 	link_fd = bpf_link__fd(link);
225 	err = verify_perf_link_info(link_fd, BPF_PERF_EVENT_EVENT, 0, 0, 0);
226 	ASSERT_OK(err, "verify_perf_link_info");
227 	bpf_link__destroy(link);
228 
229 error:
230 	close(pfd);
231 }
232 
test_uprobe_fill_link_info(struct test_fill_link_info * skel,enum bpf_perf_event_type type)233 static void test_uprobe_fill_link_info(struct test_fill_link_info *skel,
234 				       enum bpf_perf_event_type type)
235 {
236 	DECLARE_LIBBPF_OPTS(bpf_uprobe_opts, opts,
237 		.retprobe = type == BPF_PERF_EVENT_URETPROBE,
238 		.bpf_cookie = PERF_EVENT_COOKIE,
239 	);
240 	struct bpf_link *link;
241 	int link_fd, err;
242 
243 	link = bpf_program__attach_uprobe_opts(skel->progs.uprobe_run,
244 					       0, /* self pid */
245 					       UPROBE_FILE, uprobe_offset,
246 					       &opts);
247 	if (!ASSERT_OK_PTR(link, "attach_uprobe"))
248 		return;
249 
250 	link_fd = bpf_link__fd(link);
251 	err = verify_perf_link_info(link_fd, type, 0, uprobe_offset, 0);
252 	ASSERT_OK(err, "verify_perf_link_info");
253 	bpf_link__destroy(link);
254 }
255 
verify_kmulti_link_info(int fd,bool retprobe,bool has_cookies)256 static int verify_kmulti_link_info(int fd, bool retprobe, bool has_cookies)
257 {
258 	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
259 	struct bpf_link_info info;
260 	__u32 len = sizeof(info);
261 	int flags, i, err;
262 
263 	memset(&info, 0, sizeof(info));
264 
265 again:
266 	err = bpf_link_get_info_by_fd(fd, &info, &len);
267 	if (!ASSERT_OK(err, "get_link_info"))
268 		return -1;
269 
270 	if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_KPROBE_MULTI, "kmulti_type"))
271 		return -1;
272 
273 	ASSERT_EQ(info.kprobe_multi.count, KMULTI_CNT, "func_cnt");
274 	flags = info.kprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN;
275 	if (!retprobe)
276 		ASSERT_EQ(flags, 0, "kmulti_flags");
277 	else
278 		ASSERT_NEQ(flags, 0, "kretmulti_flags");
279 
280 	if (!info.kprobe_multi.addrs) {
281 		info.kprobe_multi.addrs = ptr_to_u64(addrs);
282 		info.kprobe_multi.cookies = ptr_to_u64(cookies);
283 		goto again;
284 	}
285 	for (i = 0; i < KMULTI_CNT; i++) {
286 		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
287 		ASSERT_EQ(cookies[i], has_cookies ? kmulti_cookies[i] : 0,
288 			  "kmulti_cookies_value");
289 	}
290 	return 0;
291 }
292 
verify_kmulti_invalid_user_buffer(int fd)293 static void verify_kmulti_invalid_user_buffer(int fd)
294 {
295 	__u64 addrs[KMULTI_CNT], cookies[KMULTI_CNT];
296 	struct bpf_link_info info;
297 	__u32 len = sizeof(info);
298 	int err, i;
299 
300 	memset(&info, 0, sizeof(info));
301 
302 	info.kprobe_multi.count = KMULTI_CNT;
303 	err = bpf_link_get_info_by_fd(fd, &info, &len);
304 	ASSERT_EQ(err, -EINVAL, "no_addr");
305 
306 	info.kprobe_multi.addrs = ptr_to_u64(addrs);
307 	info.kprobe_multi.count = 0;
308 	err = bpf_link_get_info_by_fd(fd, &info, &len);
309 	ASSERT_EQ(err, -EINVAL, "no_cnt");
310 
311 	for (i = 0; i < KMULTI_CNT; i++)
312 		addrs[i] = 0;
313 	info.kprobe_multi.count = KMULTI_CNT - 1;
314 	err = bpf_link_get_info_by_fd(fd, &info, &len);
315 	ASSERT_EQ(err, -ENOSPC, "smaller_cnt");
316 	for (i = 0; i < KMULTI_CNT - 1; i++)
317 		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
318 	ASSERT_EQ(addrs[i], 0, "kmulti_addrs");
319 
320 	for (i = 0; i < KMULTI_CNT; i++)
321 		addrs[i] = 0;
322 	info.kprobe_multi.count = KMULTI_CNT + 1;
323 	err = bpf_link_get_info_by_fd(fd, &info, &len);
324 	ASSERT_EQ(err, 0, "bigger_cnt");
325 	for (i = 0; i < KMULTI_CNT; i++)
326 		ASSERT_EQ(addrs[i], kmulti_addrs[i], "kmulti_addrs");
327 
328 	info.kprobe_multi.count = KMULTI_CNT;
329 	info.kprobe_multi.addrs = 0x1; /* invalid addr */
330 	err = bpf_link_get_info_by_fd(fd, &info, &len);
331 	ASSERT_EQ(err, -EFAULT, "invalid_buff_addrs");
332 
333 	info.kprobe_multi.count = KMULTI_CNT;
334 	info.kprobe_multi.addrs = ptr_to_u64(addrs);
335 	info.kprobe_multi.cookies = 0x1; /* invalid addr */
336 	err = bpf_link_get_info_by_fd(fd, &info, &len);
337 	ASSERT_EQ(err, -EFAULT, "invalid_buff_cookies");
338 
339 	/* cookies && !count */
340 	info.kprobe_multi.count = 0;
341 	info.kprobe_multi.addrs = ptr_to_u64(NULL);
342 	info.kprobe_multi.cookies = ptr_to_u64(cookies);
343 	err = bpf_link_get_info_by_fd(fd, &info, &len);
344 	ASSERT_EQ(err, -EINVAL, "invalid_cookies_count");
345 }
346 
symbols_cmp_r(const void * a,const void * b)347 static int symbols_cmp_r(const void *a, const void *b)
348 {
349 	const char **str_a = (const char **) a;
350 	const char **str_b = (const char **) b;
351 
352 	return strcmp(*str_a, *str_b);
353 }
354 
test_kprobe_multi_fill_link_info(struct test_fill_link_info * skel,bool retprobe,bool cookies,bool invalid)355 static void test_kprobe_multi_fill_link_info(struct test_fill_link_info *skel,
356 					     bool retprobe, bool cookies,
357 					     bool invalid)
358 {
359 	LIBBPF_OPTS(bpf_kprobe_multi_opts, opts);
360 	struct bpf_link *link;
361 	int link_fd, err;
362 
363 	opts.syms = kmulti_syms;
364 	opts.cookies = cookies ? kmulti_cookies : NULL;
365 	opts.cnt = KMULTI_CNT;
366 	opts.retprobe = retprobe;
367 	link = bpf_program__attach_kprobe_multi_opts(skel->progs.kmulti_run, NULL, &opts);
368 	if (!ASSERT_OK_PTR(link, "attach_kprobe_multi"))
369 		return;
370 
371 	link_fd = bpf_link__fd(link);
372 	if (!invalid) {
373 		err = verify_kmulti_link_info(link_fd, retprobe, cookies);
374 		ASSERT_OK(err, "verify_kmulti_link_info");
375 	} else {
376 		verify_kmulti_invalid_user_buffer(link_fd);
377 	}
378 	bpf_link__destroy(link);
379 }
380 
381 #define SEC(name) __attribute__((section(name), used))
382 
383 static short uprobe_link_info_sema_1 SEC(".probes");
384 static short uprobe_link_info_sema_2 SEC(".probes");
385 static short uprobe_link_info_sema_3 SEC(".probes");
386 
uprobe_link_info_func_1(void)387 noinline void uprobe_link_info_func_1(void)
388 {
389 	asm volatile ("");
390 	uprobe_link_info_sema_1++;
391 }
392 
uprobe_link_info_func_2(void)393 noinline void uprobe_link_info_func_2(void)
394 {
395 	asm volatile ("");
396 	uprobe_link_info_sema_2++;
397 }
398 
uprobe_link_info_func_3(void)399 noinline void uprobe_link_info_func_3(void)
400 {
401 	asm volatile ("");
402 	uprobe_link_info_sema_3++;
403 }
404 
405 static int
verify_umulti_link_info(int fd,bool retprobe,__u64 * offsets,__u64 * cookies,__u64 * ref_ctr_offsets)406 verify_umulti_link_info(int fd, bool retprobe, __u64 *offsets,
407 			__u64 *cookies, __u64 *ref_ctr_offsets)
408 {
409 	char path[PATH_MAX], path_buf[PATH_MAX];
410 	struct bpf_link_info info;
411 	__u32 len = sizeof(info);
412 	__u64 ref_ctr_offsets_buf[3];
413 	__u64 offsets_buf[3];
414 	__u64 cookies_buf[3];
415 	int i, err, bit;
416 	__u32 count = 0;
417 
418 	memset(path, 0, sizeof(path));
419 	err = readlink("/proc/self/exe", path, sizeof(path));
420 	if (!ASSERT_NEQ(err, -1, "readlink"))
421 		return -1;
422 
423 	memset(&info, 0, sizeof(info));
424 	err = bpf_link_get_info_by_fd(fd, &info, &len);
425 	if (!ASSERT_OK(err, "bpf_link_get_info_by_fd"))
426 		return -1;
427 
428 	ASSERT_EQ(info.uprobe_multi.count, 3, "info.uprobe_multi.count");
429 	ASSERT_EQ(info.uprobe_multi.path_size, strlen(path) + 1,
430 		  "info.uprobe_multi.path_size");
431 
432 	for (bit = 0; bit < 8; bit++) {
433 		memset(&info, 0, sizeof(info));
434 		info.uprobe_multi.path = ptr_to_u64(path_buf);
435 		info.uprobe_multi.path_size = sizeof(path_buf);
436 		info.uprobe_multi.count = count;
437 
438 		if (bit & 0x1)
439 			info.uprobe_multi.offsets = ptr_to_u64(offsets_buf);
440 		if (bit & 0x2)
441 			info.uprobe_multi.cookies = ptr_to_u64(cookies_buf);
442 		if (bit & 0x4)
443 			info.uprobe_multi.ref_ctr_offsets = ptr_to_u64(ref_ctr_offsets_buf);
444 
445 		err = bpf_link_get_info_by_fd(fd, &info, &len);
446 		if (!ASSERT_OK(err, "bpf_link_get_info_by_fd"))
447 			return -1;
448 
449 		if (!ASSERT_EQ(info.type, BPF_LINK_TYPE_UPROBE_MULTI, "info.type"))
450 			return -1;
451 
452 		ASSERT_EQ(info.uprobe_multi.pid, getpid(), "info.uprobe_multi.pid");
453 		ASSERT_EQ(info.uprobe_multi.count, 3, "info.uprobe_multi.count");
454 		ASSERT_EQ(info.uprobe_multi.flags & BPF_F_KPROBE_MULTI_RETURN,
455 			  retprobe, "info.uprobe_multi.flags.retprobe");
456 		ASSERT_EQ(info.uprobe_multi.path_size, strlen(path) + 1, "info.uprobe_multi.path_size");
457 		ASSERT_STREQ(path_buf, path, "info.uprobe_multi.path");
458 
459 		for (i = 0; i < info.uprobe_multi.count; i++) {
460 			if (info.uprobe_multi.offsets)
461 				ASSERT_EQ(offsets_buf[i], offsets[i], "info.uprobe_multi.offsets");
462 			if (info.uprobe_multi.cookies)
463 				ASSERT_EQ(cookies_buf[i], cookies[i], "info.uprobe_multi.cookies");
464 			if (info.uprobe_multi.ref_ctr_offsets) {
465 				ASSERT_EQ(ref_ctr_offsets_buf[i], ref_ctr_offsets[i],
466 					  "info.uprobe_multi.ref_ctr_offsets");
467 			}
468 		}
469 		count = count ?: info.uprobe_multi.count;
470 	}
471 
472 	return 0;
473 }
474 
verify_umulti_invalid_user_buffer(int fd)475 static void verify_umulti_invalid_user_buffer(int fd)
476 {
477 	struct bpf_link_info info;
478 	__u32 len = sizeof(info);
479 	__u64 buf[3];
480 	int err;
481 
482 	/* upath_size defined, not path */
483 	memset(&info, 0, sizeof(info));
484 	info.uprobe_multi.path_size = 3;
485 	err = bpf_link_get_info_by_fd(fd, &info, &len);
486 	ASSERT_EQ(err, -EINVAL, "failed_upath_size");
487 
488 	/* path defined, but small */
489 	memset(&info, 0, sizeof(info));
490 	info.uprobe_multi.path = ptr_to_u64(buf);
491 	info.uprobe_multi.path_size = 3;
492 	err = bpf_link_get_info_by_fd(fd, &info, &len);
493 	ASSERT_LT(err, 0, "failed_upath_small");
494 
495 	/* path has wrong pointer */
496 	memset(&info, 0, sizeof(info));
497 	info.uprobe_multi.path_size = PATH_MAX;
498 	info.uprobe_multi.path = 123;
499 	err = bpf_link_get_info_by_fd(fd, &info, &len);
500 	ASSERT_EQ(err, -EFAULT, "failed_bad_path_ptr");
501 
502 	/* count zero, with offsets */
503 	memset(&info, 0, sizeof(info));
504 	info.uprobe_multi.offsets = ptr_to_u64(buf);
505 	err = bpf_link_get_info_by_fd(fd, &info, &len);
506 	ASSERT_EQ(err, -EINVAL, "failed_count");
507 
508 	/* offsets not big enough */
509 	memset(&info, 0, sizeof(info));
510 	info.uprobe_multi.offsets = ptr_to_u64(buf);
511 	info.uprobe_multi.count = 2;
512 	err = bpf_link_get_info_by_fd(fd, &info, &len);
513 	ASSERT_EQ(err, -ENOSPC, "failed_small_count");
514 
515 	/* offsets has wrong pointer */
516 	memset(&info, 0, sizeof(info));
517 	info.uprobe_multi.offsets = 123;
518 	info.uprobe_multi.count = 3;
519 	err = bpf_link_get_info_by_fd(fd, &info, &len);
520 	ASSERT_EQ(err, -EFAULT, "failed_wrong_offsets");
521 }
522 
test_uprobe_multi_fill_link_info(struct test_fill_link_info * skel,bool retprobe,bool invalid)523 static void test_uprobe_multi_fill_link_info(struct test_fill_link_info *skel,
524 					     bool retprobe, bool invalid)
525 {
526 	LIBBPF_OPTS(bpf_uprobe_multi_opts, opts,
527 		.retprobe = retprobe,
528 	);
529 	const char *syms[3] = {
530 		"uprobe_link_info_func_1",
531 		"uprobe_link_info_func_2",
532 		"uprobe_link_info_func_3",
533 	};
534 	__u64 cookies[3] = {
535 		0xdead,
536 		0xbeef,
537 		0xcafe,
538 	};
539 	const char *sema[3] = {
540 		"uprobe_link_info_sema_1",
541 		"uprobe_link_info_sema_2",
542 		"uprobe_link_info_sema_3",
543 	};
544 	__u64 *offsets = NULL, *ref_ctr_offsets;
545 	struct bpf_link *link;
546 	int link_fd, err;
547 
548 	err = elf_resolve_syms_offsets("/proc/self/exe", 3, sema,
549 				       (unsigned long **) &ref_ctr_offsets, STT_OBJECT);
550 	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_object"))
551 		return;
552 
553 	err = elf_resolve_syms_offsets("/proc/self/exe", 3, syms,
554 				       (unsigned long **) &offsets, STT_FUNC);
555 	if (!ASSERT_OK(err, "elf_resolve_syms_offsets_func"))
556 		goto out;
557 
558 	opts.syms = syms;
559 	opts.cookies = &cookies[0];
560 	opts.ref_ctr_offsets = (unsigned long *) &ref_ctr_offsets[0];
561 	opts.cnt = ARRAY_SIZE(syms);
562 
563 	link = bpf_program__attach_uprobe_multi(skel->progs.umulti_run, 0,
564 						"/proc/self/exe", NULL, &opts);
565 	if (!ASSERT_OK_PTR(link, "bpf_program__attach_uprobe_multi"))
566 		goto out;
567 
568 	link_fd = bpf_link__fd(link);
569 	if (invalid)
570 		verify_umulti_invalid_user_buffer(link_fd);
571 	else
572 		verify_umulti_link_info(link_fd, retprobe, offsets, cookies, ref_ctr_offsets);
573 
574 	bpf_link__destroy(link);
575 out:
576 	free(ref_ctr_offsets);
577 	free(offsets);
578 }
579 
test_fill_link_info(void)580 void test_fill_link_info(void)
581 {
582 	struct test_fill_link_info *skel;
583 	int i;
584 
585 	skel = test_fill_link_info__open_and_load();
586 	if (!ASSERT_OK_PTR(skel, "skel_open"))
587 		return;
588 
589 	/* load kallsyms to compare the addr */
590 	if (!ASSERT_OK(load_kallsyms(), "load_kallsyms"))
591 		goto cleanup;
592 
593 	kprobe_addr = ksym_get_addr(KPROBE_FUNC);
594 	if (test__start_subtest("kprobe_link_info"))
595 		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, false);
596 	if (test__start_subtest("kretprobe_link_info"))
597 		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KRETPROBE, false);
598 	if (test__start_subtest("kprobe_invalid_ubuff"))
599 		test_kprobe_fill_link_info(skel, BPF_PERF_EVENT_KPROBE, true);
600 	if (test__start_subtest("tracepoint_link_info"))
601 		test_tp_fill_link_info(skel);
602 	if (test__start_subtest("event_link_info"))
603 		test_event_fill_link_info(skel);
604 
605 	uprobe_offset = get_uprobe_offset(&uprobe_func);
606 	if (test__start_subtest("uprobe_link_info"))
607 		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_UPROBE);
608 	if (test__start_subtest("uretprobe_link_info"))
609 		test_uprobe_fill_link_info(skel, BPF_PERF_EVENT_URETPROBE);
610 
611 	qsort(kmulti_syms, KMULTI_CNT, sizeof(kmulti_syms[0]), symbols_cmp_r);
612 	for (i = 0; i < KMULTI_CNT; i++)
613 		kmulti_addrs[i] = ksym_get_addr(kmulti_syms[i]);
614 	if (test__start_subtest("kprobe_multi_link_info")) {
615 		test_kprobe_multi_fill_link_info(skel, false, false, false);
616 		test_kprobe_multi_fill_link_info(skel, false, true, false);
617 	}
618 	if (test__start_subtest("kretprobe_multi_link_info")) {
619 		test_kprobe_multi_fill_link_info(skel, true, false, false);
620 		test_kprobe_multi_fill_link_info(skel, true, true, false);
621 	}
622 	if (test__start_subtest("kprobe_multi_invalid_ubuff"))
623 		test_kprobe_multi_fill_link_info(skel, true, true, true);
624 
625 	if (test__start_subtest("uprobe_multi_link_info"))
626 		test_uprobe_multi_fill_link_info(skel, false, false);
627 	if (test__start_subtest("uretprobe_multi_link_info"))
628 		test_uprobe_multi_fill_link_info(skel, true, false);
629 	if (test__start_subtest("uprobe_multi_invalid"))
630 		test_uprobe_multi_fill_link_info(skel, false, true);
631 
632 cleanup:
633 	test_fill_link_info__destroy(skel);
634 }
635