xref: /linux/tools/testing/selftests/bpf/prog_tests/bpf_iter.c (revision 3d5ad2d4eca337e80f38df77de89614aa5aaceb9)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2020 Facebook */
3 #include <test_progs.h>
4 #include <unistd.h>
5 #include <sys/syscall.h>
6 #include <task_local_storage_helpers.h>
7 #include "bpf_iter_ipv6_route.skel.h"
8 #include "bpf_iter_netlink.skel.h"
9 #include "bpf_iter_bpf_map.skel.h"
10 #include "bpf_iter_tasks.skel.h"
11 #include "bpf_iter_task_stack.skel.h"
12 #include "bpf_iter_task_file.skel.h"
13 #include "bpf_iter_task_vmas.skel.h"
14 #include "bpf_iter_task_btf.skel.h"
15 #include "bpf_iter_tcp4.skel.h"
16 #include "bpf_iter_tcp6.skel.h"
17 #include "bpf_iter_udp4.skel.h"
18 #include "bpf_iter_udp6.skel.h"
19 #include "bpf_iter_unix.skel.h"
20 #include "bpf_iter_vma_offset.skel.h"
21 #include "bpf_iter_test_kern1.skel.h"
22 #include "bpf_iter_test_kern2.skel.h"
23 #include "bpf_iter_test_kern3.skel.h"
24 #include "bpf_iter_test_kern4.skel.h"
25 #include "bpf_iter_bpf_hash_map.skel.h"
26 #include "bpf_iter_bpf_percpu_hash_map.skel.h"
27 #include "bpf_iter_bpf_array_map.skel.h"
28 #include "bpf_iter_bpf_percpu_array_map.skel.h"
29 #include "bpf_iter_bpf_sk_storage_helpers.skel.h"
30 #include "bpf_iter_bpf_sk_storage_map.skel.h"
31 #include "bpf_iter_test_kern5.skel.h"
32 #include "bpf_iter_test_kern6.skel.h"
33 #include "bpf_iter_bpf_link.skel.h"
34 #include "bpf_iter_ksym.skel.h"
35 #include "bpf_iter_sockmap.skel.h"
36 
test_btf_id_or_null(void)37 static void test_btf_id_or_null(void)
38 {
39 	struct bpf_iter_test_kern3 *skel;
40 
41 	skel = bpf_iter_test_kern3__open_and_load();
42 	if (!ASSERT_ERR_PTR(skel, "bpf_iter_test_kern3__open_and_load")) {
43 		bpf_iter_test_kern3__destroy(skel);
44 		return;
45 	}
46 }
47 
do_dummy_read_opts(struct bpf_program * prog,struct bpf_iter_attach_opts * opts)48 static void do_dummy_read_opts(struct bpf_program *prog, struct bpf_iter_attach_opts *opts)
49 {
50 	struct bpf_link *link;
51 	char buf[16] = {};
52 	int iter_fd, len;
53 
54 	link = bpf_program__attach_iter(prog, opts);
55 	if (!ASSERT_OK_PTR(link, "attach_iter"))
56 		return;
57 
58 	iter_fd = bpf_iter_create(bpf_link__fd(link));
59 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
60 		goto free_link;
61 
62 	/* not check contents, but ensure read() ends without error */
63 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
64 		;
65 	ASSERT_GE(len, 0, "read");
66 
67 	close(iter_fd);
68 
69 free_link:
70 	bpf_link__destroy(link);
71 }
72 
do_dummy_read(struct bpf_program * prog)73 static void do_dummy_read(struct bpf_program *prog)
74 {
75 	do_dummy_read_opts(prog, NULL);
76 }
77 
do_read_map_iter_fd(struct bpf_object_skeleton ** skel,struct bpf_program * prog,struct bpf_map * map)78 static void do_read_map_iter_fd(struct bpf_object_skeleton **skel, struct bpf_program *prog,
79 				struct bpf_map *map)
80 {
81 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
82 	union bpf_iter_link_info linfo;
83 	struct bpf_link *link;
84 	char buf[16] = {};
85 	int iter_fd, len;
86 
87 	memset(&linfo, 0, sizeof(linfo));
88 	linfo.map.map_fd = bpf_map__fd(map);
89 	opts.link_info = &linfo;
90 	opts.link_info_len = sizeof(linfo);
91 	link = bpf_program__attach_iter(prog, &opts);
92 	if (!ASSERT_OK_PTR(link, "attach_map_iter"))
93 		return;
94 
95 	iter_fd = bpf_iter_create(bpf_link__fd(link));
96 	if (!ASSERT_GE(iter_fd, 0, "create_map_iter")) {
97 		bpf_link__destroy(link);
98 		return;
99 	}
100 
101 	/* Close link and map fd prematurely */
102 	bpf_link__destroy(link);
103 	bpf_object__destroy_skeleton(*skel);
104 	*skel = NULL;
105 
106 	/* Try to let map free work to run first if map is freed */
107 	usleep(100);
108 	/* Memory used by both sock map and sock local storage map are
109 	 * freed after two synchronize_rcu() calls, so wait for it
110 	 */
111 	kern_sync_rcu();
112 	kern_sync_rcu();
113 
114 	/* Read after both map fd and link fd are closed */
115 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
116 		;
117 	ASSERT_GE(len, 0, "read_iterator");
118 
119 	close(iter_fd);
120 }
121 
read_fd_into_buffer(int fd,char * buf,int size)122 static int read_fd_into_buffer(int fd, char *buf, int size)
123 {
124 	int bufleft = size;
125 	int len;
126 
127 	do {
128 		len = read(fd, buf, bufleft);
129 		if (len > 0) {
130 			buf += len;
131 			bufleft -= len;
132 		}
133 	} while (len > 0);
134 
135 	return len < 0 ? len : size - bufleft;
136 }
137 
test_ipv6_route(void)138 static void test_ipv6_route(void)
139 {
140 	struct bpf_iter_ipv6_route *skel;
141 
142 	skel = bpf_iter_ipv6_route__open_and_load();
143 	if (!ASSERT_OK_PTR(skel, "bpf_iter_ipv6_route__open_and_load"))
144 		return;
145 
146 	do_dummy_read(skel->progs.dump_ipv6_route);
147 
148 	bpf_iter_ipv6_route__destroy(skel);
149 }
150 
test_netlink(void)151 static void test_netlink(void)
152 {
153 	struct bpf_iter_netlink *skel;
154 
155 	skel = bpf_iter_netlink__open_and_load();
156 	if (!ASSERT_OK_PTR(skel, "bpf_iter_netlink__open_and_load"))
157 		return;
158 
159 	do_dummy_read(skel->progs.dump_netlink);
160 
161 	bpf_iter_netlink__destroy(skel);
162 }
163 
test_bpf_map(void)164 static void test_bpf_map(void)
165 {
166 	struct bpf_iter_bpf_map *skel;
167 
168 	skel = bpf_iter_bpf_map__open_and_load();
169 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_map__open_and_load"))
170 		return;
171 
172 	do_dummy_read(skel->progs.dump_bpf_map);
173 
174 	bpf_iter_bpf_map__destroy(skel);
175 }
176 
check_bpf_link_info(const struct bpf_program * prog)177 static void check_bpf_link_info(const struct bpf_program *prog)
178 {
179 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
180 	union bpf_iter_link_info linfo;
181 	struct bpf_link_info info = {};
182 	struct bpf_link *link;
183 	__u32 info_len;
184 	int err;
185 
186 	memset(&linfo, 0, sizeof(linfo));
187 	linfo.task.tid = getpid();
188 	opts.link_info = &linfo;
189 	opts.link_info_len = sizeof(linfo);
190 
191 	link = bpf_program__attach_iter(prog, &opts);
192 	if (!ASSERT_OK_PTR(link, "attach_iter"))
193 		return;
194 
195 	info_len = sizeof(info);
196 	err = bpf_link_get_info_by_fd(bpf_link__fd(link), &info, &info_len);
197 	ASSERT_OK(err, "bpf_link_get_info_by_fd");
198 	ASSERT_EQ(info.iter.task.tid, getpid(), "check_task_tid");
199 
200 	bpf_link__destroy(link);
201 }
202 
203 static pthread_mutex_t do_nothing_mutex;
204 
do_nothing_wait(void * arg)205 static void *do_nothing_wait(void *arg)
206 {
207 	pthread_mutex_lock(&do_nothing_mutex);
208 	pthread_mutex_unlock(&do_nothing_mutex);
209 
210 	pthread_exit(arg);
211 }
212 
test_task_common_nocheck(struct bpf_iter_attach_opts * opts,int * num_unknown,int * num_known)213 static void test_task_common_nocheck(struct bpf_iter_attach_opts *opts,
214 				     int *num_unknown, int *num_known)
215 {
216 	struct bpf_iter_tasks *skel;
217 	pthread_t thread_id;
218 	void *ret;
219 
220 	skel = bpf_iter_tasks__open_and_load();
221 	if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load"))
222 		return;
223 
224 	ASSERT_OK(pthread_mutex_lock(&do_nothing_mutex), "pthread_mutex_lock");
225 
226 	ASSERT_OK(pthread_create(&thread_id, NULL, &do_nothing_wait, NULL),
227 		  "pthread_create");
228 
229 	skel->bss->tid = gettid();
230 
231 	do_dummy_read_opts(skel->progs.dump_task, opts);
232 
233 	*num_unknown = skel->bss->num_unknown_tid;
234 	*num_known = skel->bss->num_known_tid;
235 
236 	ASSERT_OK(pthread_mutex_unlock(&do_nothing_mutex), "pthread_mutex_unlock");
237 	ASSERT_FALSE(pthread_join(thread_id, &ret) || ret != NULL,
238 		     "pthread_join");
239 
240 	bpf_iter_tasks__destroy(skel);
241 }
242 
test_task_common(struct bpf_iter_attach_opts * opts,int num_unknown,int num_known)243 static void test_task_common(struct bpf_iter_attach_opts *opts, int num_unknown, int num_known)
244 {
245 	int num_unknown_tid, num_known_tid;
246 
247 	test_task_common_nocheck(opts, &num_unknown_tid, &num_known_tid);
248 	ASSERT_EQ(num_unknown_tid, num_unknown, "check_num_unknown_tid");
249 	ASSERT_EQ(num_known_tid, num_known, "check_num_known_tid");
250 }
251 
run_test_task_tid(void * arg)252 static void *run_test_task_tid(void *arg)
253 {
254 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
255 	union bpf_iter_link_info linfo;
256 	int num_unknown_tid, num_known_tid;
257 
258 	ASSERT_NEQ(getpid(), gettid(), "check_new_thread_id");
259 
260 	memset(&linfo, 0, sizeof(linfo));
261 	linfo.task.tid = gettid();
262 	opts.link_info = &linfo;
263 	opts.link_info_len = sizeof(linfo);
264 	test_task_common(&opts, 0, 1);
265 
266 	linfo.task.tid = 0;
267 	linfo.task.pid = getpid();
268 	/* This includes the parent thread, this thread,
269 	 * and the do_nothing_wait thread
270 	 */
271 	test_task_common(&opts, 2, 1);
272 
273 	test_task_common_nocheck(NULL, &num_unknown_tid, &num_known_tid);
274 	ASSERT_GT(num_unknown_tid, 2, "check_num_unknown_tid");
275 	ASSERT_EQ(num_known_tid, 1, "check_num_known_tid");
276 
277 	return NULL;
278 }
279 
test_task_tid(void)280 static void test_task_tid(void)
281 {
282 	pthread_t thread_id;
283 
284 	/* Create a new thread so pid and tid aren't the same */
285 	ASSERT_OK(pthread_create(&thread_id, NULL, &run_test_task_tid, NULL),
286 		  "pthread_create");
287 	ASSERT_FALSE(pthread_join(thread_id, NULL), "pthread_join");
288 }
289 
test_task_pid(void)290 static void test_task_pid(void)
291 {
292 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
293 	union bpf_iter_link_info linfo;
294 
295 	memset(&linfo, 0, sizeof(linfo));
296 	linfo.task.pid = getpid();
297 	opts.link_info = &linfo;
298 	opts.link_info_len = sizeof(linfo);
299 
300 	test_task_common(&opts, 1, 1);
301 }
302 
test_task_pidfd(void)303 static void test_task_pidfd(void)
304 {
305 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
306 	union bpf_iter_link_info linfo;
307 	int pidfd;
308 
309 	pidfd = sys_pidfd_open(getpid(), 0);
310 	if (!ASSERT_GT(pidfd, 0, "sys_pidfd_open"))
311 		return;
312 
313 	memset(&linfo, 0, sizeof(linfo));
314 	linfo.task.pid_fd = pidfd;
315 	opts.link_info = &linfo;
316 	opts.link_info_len = sizeof(linfo);
317 
318 	test_task_common(&opts, 1, 1);
319 
320 	close(pidfd);
321 }
322 
test_task_sleepable(void)323 static void test_task_sleepable(void)
324 {
325 	struct bpf_iter_tasks *skel;
326 
327 	skel = bpf_iter_tasks__open_and_load();
328 	if (!ASSERT_OK_PTR(skel, "bpf_iter_tasks__open_and_load"))
329 		return;
330 
331 	do_dummy_read(skel->progs.dump_task_sleepable);
332 
333 	ASSERT_GT(skel->bss->num_expected_failure_copy_from_user_task, 0,
334 		  "num_expected_failure_copy_from_user_task");
335 	ASSERT_GT(skel->bss->num_success_copy_from_user_task, 0,
336 		  "num_success_copy_from_user_task");
337 
338 	bpf_iter_tasks__destroy(skel);
339 }
340 
test_task_stack(void)341 static void test_task_stack(void)
342 {
343 	struct bpf_iter_task_stack *skel;
344 
345 	skel = bpf_iter_task_stack__open_and_load();
346 	if (!ASSERT_OK_PTR(skel, "bpf_iter_task_stack__open_and_load"))
347 		return;
348 
349 	do_dummy_read(skel->progs.dump_task_stack);
350 	do_dummy_read(skel->progs.get_task_user_stacks);
351 
352 	ASSERT_EQ(skel->bss->num_user_stacks, 1, "num_user_stacks");
353 
354 	bpf_iter_task_stack__destroy(skel);
355 }
356 
test_task_file(void)357 static void test_task_file(void)
358 {
359 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
360 	struct bpf_iter_task_file *skel;
361 	union bpf_iter_link_info linfo;
362 	pthread_t thread_id;
363 	void *ret;
364 
365 	skel = bpf_iter_task_file__open_and_load();
366 	if (!ASSERT_OK_PTR(skel, "bpf_iter_task_file__open_and_load"))
367 		return;
368 
369 	skel->bss->tgid = getpid();
370 
371 	ASSERT_OK(pthread_mutex_lock(&do_nothing_mutex), "pthread_mutex_lock");
372 
373 	ASSERT_OK(pthread_create(&thread_id, NULL, &do_nothing_wait, NULL),
374 		  "pthread_create");
375 
376 	memset(&linfo, 0, sizeof(linfo));
377 	linfo.task.tid = getpid();
378 	opts.link_info = &linfo;
379 	opts.link_info_len = sizeof(linfo);
380 
381 	do_dummy_read_opts(skel->progs.dump_task_file, &opts);
382 
383 	ASSERT_EQ(skel->bss->count, 0, "check_count");
384 	ASSERT_EQ(skel->bss->unique_tgid_count, 1, "check_unique_tgid_count");
385 
386 	skel->bss->last_tgid = 0;
387 	skel->bss->count = 0;
388 	skel->bss->unique_tgid_count = 0;
389 
390 	do_dummy_read(skel->progs.dump_task_file);
391 
392 	ASSERT_EQ(skel->bss->count, 0, "check_count");
393 	ASSERT_GT(skel->bss->unique_tgid_count, 1, "check_unique_tgid_count");
394 
395 	check_bpf_link_info(skel->progs.dump_task_file);
396 
397 	ASSERT_OK(pthread_mutex_unlock(&do_nothing_mutex), "pthread_mutex_unlock");
398 	ASSERT_OK(pthread_join(thread_id, &ret), "pthread_join");
399 	ASSERT_NULL(ret, "pthread_join");
400 
401 	bpf_iter_task_file__destroy(skel);
402 }
403 
404 #define TASKBUFSZ		32768
405 
406 static char taskbuf[TASKBUFSZ];
407 
do_btf_read(struct bpf_iter_task_btf * skel)408 static int do_btf_read(struct bpf_iter_task_btf *skel)
409 {
410 	struct bpf_program *prog = skel->progs.dump_task_struct;
411 	struct bpf_iter_task_btf__bss *bss = skel->bss;
412 	int iter_fd = -1, err;
413 	struct bpf_link *link;
414 	char *buf = taskbuf;
415 	int ret = 0;
416 
417 	link = bpf_program__attach_iter(prog, NULL);
418 	if (!ASSERT_OK_PTR(link, "attach_iter"))
419 		return ret;
420 
421 	iter_fd = bpf_iter_create(bpf_link__fd(link));
422 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
423 		goto free_link;
424 
425 	err = read_fd_into_buffer(iter_fd, buf, TASKBUFSZ);
426 	if (bss->skip) {
427 		printf("%s:SKIP:no __builtin_btf_type_id\n", __func__);
428 		ret = 1;
429 		test__skip();
430 		goto free_link;
431 	}
432 
433 	if (!ASSERT_GE(err, 0, "read"))
434 		goto free_link;
435 
436 	ASSERT_HAS_SUBSTR(taskbuf, "(struct task_struct)",
437 	      "check for btf representation of task_struct in iter data");
438 free_link:
439 	if (iter_fd > 0)
440 		close(iter_fd);
441 	bpf_link__destroy(link);
442 	return ret;
443 }
444 
test_task_btf(void)445 static void test_task_btf(void)
446 {
447 	struct bpf_iter_task_btf__bss *bss;
448 	struct bpf_iter_task_btf *skel;
449 	int ret;
450 
451 	skel = bpf_iter_task_btf__open_and_load();
452 	if (!ASSERT_OK_PTR(skel, "bpf_iter_task_btf__open_and_load"))
453 		return;
454 
455 	bss = skel->bss;
456 
457 	ret = do_btf_read(skel);
458 	if (ret)
459 		goto cleanup;
460 
461 	if (!ASSERT_NEQ(bss->tasks, 0, "no task iteration, did BPF program run?"))
462 		goto cleanup;
463 
464 	ASSERT_EQ(bss->seq_err, 0, "check for unexpected err");
465 
466 cleanup:
467 	bpf_iter_task_btf__destroy(skel);
468 }
469 
test_tcp4(void)470 static void test_tcp4(void)
471 {
472 	struct bpf_iter_tcp4 *skel;
473 
474 	skel = bpf_iter_tcp4__open_and_load();
475 	if (!ASSERT_OK_PTR(skel, "bpf_iter_tcp4__open_and_load"))
476 		return;
477 
478 	do_dummy_read(skel->progs.dump_tcp4);
479 
480 	bpf_iter_tcp4__destroy(skel);
481 }
482 
test_tcp6(void)483 static void test_tcp6(void)
484 {
485 	struct bpf_iter_tcp6 *skel;
486 
487 	skel = bpf_iter_tcp6__open_and_load();
488 	if (!ASSERT_OK_PTR(skel, "bpf_iter_tcp6__open_and_load"))
489 		return;
490 
491 	do_dummy_read(skel->progs.dump_tcp6);
492 
493 	bpf_iter_tcp6__destroy(skel);
494 }
495 
test_udp4(void)496 static void test_udp4(void)
497 {
498 	struct bpf_iter_udp4 *skel;
499 
500 	skel = bpf_iter_udp4__open_and_load();
501 	if (!ASSERT_OK_PTR(skel, "bpf_iter_udp4__open_and_load"))
502 		return;
503 
504 	do_dummy_read(skel->progs.dump_udp4);
505 
506 	bpf_iter_udp4__destroy(skel);
507 }
508 
test_udp6(void)509 static void test_udp6(void)
510 {
511 	struct bpf_iter_udp6 *skel;
512 
513 	skel = bpf_iter_udp6__open_and_load();
514 	if (!ASSERT_OK_PTR(skel, "bpf_iter_udp6__open_and_load"))
515 		return;
516 
517 	do_dummy_read(skel->progs.dump_udp6);
518 
519 	bpf_iter_udp6__destroy(skel);
520 }
521 
test_unix(void)522 static void test_unix(void)
523 {
524 	struct bpf_iter_unix *skel;
525 
526 	skel = bpf_iter_unix__open_and_load();
527 	if (!ASSERT_OK_PTR(skel, "bpf_iter_unix__open_and_load"))
528 		return;
529 
530 	do_dummy_read(skel->progs.dump_unix);
531 
532 	bpf_iter_unix__destroy(skel);
533 }
534 
535 /* The expected string is less than 16 bytes */
do_read_with_fd(int iter_fd,const char * expected,bool read_one_char)536 static int do_read_with_fd(int iter_fd, const char *expected,
537 			   bool read_one_char)
538 {
539 	int len, read_buf_len, start;
540 	char buf[16] = {};
541 
542 	read_buf_len = read_one_char ? 1 : 16;
543 	start = 0;
544 	while ((len = read(iter_fd, buf + start, read_buf_len)) > 0) {
545 		start += len;
546 		if (!ASSERT_LT(start, 16, "read"))
547 			return -1;
548 		read_buf_len = read_one_char ? 1 : 16 - start;
549 	}
550 	if (!ASSERT_GE(len, 0, "read"))
551 		return -1;
552 
553 	if (!ASSERT_STREQ(buf, expected, "read"))
554 		return -1;
555 
556 	return 0;
557 }
558 
test_anon_iter(bool read_one_char)559 static void test_anon_iter(bool read_one_char)
560 {
561 	struct bpf_iter_test_kern1 *skel;
562 	struct bpf_link *link;
563 	int iter_fd, err;
564 
565 	skel = bpf_iter_test_kern1__open_and_load();
566 	if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern1__open_and_load"))
567 		return;
568 
569 	err = bpf_iter_test_kern1__attach(skel);
570 	if (!ASSERT_OK(err, "bpf_iter_test_kern1__attach")) {
571 		goto out;
572 	}
573 
574 	link = skel->links.dump_task;
575 	iter_fd = bpf_iter_create(bpf_link__fd(link));
576 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
577 		goto out;
578 
579 	do_read_with_fd(iter_fd, "abcd", read_one_char);
580 	close(iter_fd);
581 
582 out:
583 	bpf_iter_test_kern1__destroy(skel);
584 }
585 
do_read(const char * path,const char * expected)586 static int do_read(const char *path, const char *expected)
587 {
588 	int err, iter_fd;
589 
590 	iter_fd = open(path, O_RDONLY);
591 	if (!ASSERT_GE(iter_fd, 0, "open"))
592 		return -1;
593 
594 	err = do_read_with_fd(iter_fd, expected, false);
595 	close(iter_fd);
596 	return err;
597 }
598 
test_file_iter(void)599 static void test_file_iter(void)
600 {
601 	const char *path = "/sys/fs/bpf/bpf_iter_test1";
602 	struct bpf_iter_test_kern1 *skel1;
603 	struct bpf_iter_test_kern2 *skel2;
604 	struct bpf_link *link;
605 	int err;
606 
607 	skel1 = bpf_iter_test_kern1__open_and_load();
608 	if (!ASSERT_OK_PTR(skel1, "bpf_iter_test_kern1__open_and_load"))
609 		return;
610 
611 	link = bpf_program__attach_iter(skel1->progs.dump_task, NULL);
612 	if (!ASSERT_OK_PTR(link, "attach_iter"))
613 		goto out;
614 
615 	/* unlink this path if it exists. */
616 	unlink(path);
617 
618 	err = bpf_link__pin(link, path);
619 	if (!ASSERT_OK(err, "pin_iter"))
620 		goto free_link;
621 
622 	err = do_read(path, "abcd");
623 	if (err)
624 		goto unlink_path;
625 
626 	/* file based iterator seems working fine. Let us a link update
627 	 * of the underlying link and `cat` the iterator again, its content
628 	 * should change.
629 	 */
630 	skel2 = bpf_iter_test_kern2__open_and_load();
631 	if (!ASSERT_OK_PTR(skel2, "bpf_iter_test_kern2__open_and_load"))
632 		goto unlink_path;
633 
634 	err = bpf_link__update_program(link, skel2->progs.dump_task);
635 	if (!ASSERT_OK(err, "update_prog"))
636 		goto destroy_skel2;
637 
638 	do_read(path, "ABCD");
639 
640 destroy_skel2:
641 	bpf_iter_test_kern2__destroy(skel2);
642 unlink_path:
643 	unlink(path);
644 free_link:
645 	bpf_link__destroy(link);
646 out:
647 	bpf_iter_test_kern1__destroy(skel1);
648 }
649 
test_overflow(bool test_e2big_overflow,bool ret1)650 static void test_overflow(bool test_e2big_overflow, bool ret1)
651 {
652 	__u32 map_info_len, total_read_len, expected_read_len;
653 	int err, iter_fd, map1_fd, map2_fd, len;
654 	struct bpf_map_info map_info = {};
655 	struct bpf_iter_test_kern4 *skel;
656 	struct bpf_link *link;
657 	__u32 iter_size;
658 	char *buf;
659 
660 	skel = bpf_iter_test_kern4__open();
661 	if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern4__open"))
662 		return;
663 
664 	/* create two maps: bpf program will only do bpf_seq_write
665 	 * for these two maps. The goal is one map output almost
666 	 * fills seq_file buffer and then the other will trigger
667 	 * overflow and needs restart.
668 	 */
669 	map1_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL);
670 	if (!ASSERT_GE(map1_fd, 0, "bpf_map_create"))
671 		goto out;
672 	map2_fd = bpf_map_create(BPF_MAP_TYPE_ARRAY, NULL, 4, 8, 1, NULL);
673 	if (!ASSERT_GE(map2_fd, 0, "bpf_map_create"))
674 		goto free_map1;
675 
676 	/* bpf_seq_printf kernel buffer is 8 pages, so one map
677 	 * bpf_seq_write will mostly fill it, and the other map
678 	 * will partially fill and then trigger overflow and need
679 	 * bpf_seq_read restart.
680 	 */
681 	iter_size = sysconf(_SC_PAGE_SIZE) << 3;
682 
683 	if (test_e2big_overflow) {
684 		skel->rodata->print_len = (iter_size + 8) / 8;
685 		expected_read_len = 2 * (iter_size + 8);
686 	} else if (!ret1) {
687 		skel->rodata->print_len = (iter_size - 8) / 8;
688 		expected_read_len = 2 * (iter_size - 8);
689 	} else {
690 		skel->rodata->print_len = 1;
691 		expected_read_len = 2 * 8;
692 	}
693 	skel->rodata->ret1 = ret1;
694 
695 	if (!ASSERT_OK(bpf_iter_test_kern4__load(skel),
696 		  "bpf_iter_test_kern4__load"))
697 		goto free_map2;
698 
699 	/* setup filtering map_id in bpf program */
700 	map_info_len = sizeof(map_info);
701 	err = bpf_map_get_info_by_fd(map1_fd, &map_info, &map_info_len);
702 	if (!ASSERT_OK(err, "get_map_info"))
703 		goto free_map2;
704 	skel->bss->map1_id = map_info.id;
705 
706 	err = bpf_map_get_info_by_fd(map2_fd, &map_info, &map_info_len);
707 	if (!ASSERT_OK(err, "get_map_info"))
708 		goto free_map2;
709 	skel->bss->map2_id = map_info.id;
710 
711 	link = bpf_program__attach_iter(skel->progs.dump_bpf_map, NULL);
712 	if (!ASSERT_OK_PTR(link, "attach_iter"))
713 		goto free_map2;
714 
715 	iter_fd = bpf_iter_create(bpf_link__fd(link));
716 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
717 		goto free_link;
718 
719 	buf = malloc(expected_read_len);
720 	if (!ASSERT_OK_PTR(buf, "malloc"))
721 		goto close_iter;
722 
723 	/* do read */
724 	total_read_len = 0;
725 	if (test_e2big_overflow) {
726 		while ((len = read(iter_fd, buf, expected_read_len)) > 0)
727 			total_read_len += len;
728 
729 		ASSERT_EQ(len, -1, "read");
730 		ASSERT_EQ(errno, E2BIG, "read");
731 		goto free_buf;
732 	} else if (!ret1) {
733 		while ((len = read(iter_fd, buf, expected_read_len)) > 0)
734 			total_read_len += len;
735 
736 		if (!ASSERT_GE(len, 0, "read"))
737 			goto free_buf;
738 	} else {
739 		do {
740 			len = read(iter_fd, buf, expected_read_len);
741 			if (len > 0)
742 				total_read_len += len;
743 		} while (len > 0 || len == -EAGAIN);
744 
745 		if (!ASSERT_GE(len, 0, "read"))
746 			goto free_buf;
747 	}
748 
749 	if (!ASSERT_EQ(total_read_len, expected_read_len, "read"))
750 		goto free_buf;
751 
752 	if (!ASSERT_EQ(skel->bss->map1_accessed, 1, "map1_accessed"))
753 		goto free_buf;
754 
755 	if (!ASSERT_EQ(skel->bss->map2_accessed, 2, "map2_accessed"))
756 		goto free_buf;
757 
758 	ASSERT_EQ(skel->bss->map2_seqnum1, skel->bss->map2_seqnum2, "map2_seqnum");
759 
760 free_buf:
761 	free(buf);
762 close_iter:
763 	close(iter_fd);
764 free_link:
765 	bpf_link__destroy(link);
766 free_map2:
767 	close(map2_fd);
768 free_map1:
769 	close(map1_fd);
770 out:
771 	bpf_iter_test_kern4__destroy(skel);
772 }
773 
test_bpf_hash_map(void)774 static void test_bpf_hash_map(void)
775 {
776 	__u32 expected_key_a = 0, expected_key_b = 0;
777 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
778 	struct bpf_iter_bpf_hash_map *skel;
779 	int err, i, len, map_fd, iter_fd;
780 	union bpf_iter_link_info linfo;
781 	__u64 val, expected_val = 0;
782 	struct bpf_link *link;
783 	struct key_t {
784 		int a;
785 		int b;
786 		int c;
787 	} key;
788 	char buf[64];
789 
790 	skel = bpf_iter_bpf_hash_map__open();
791 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_hash_map__open"))
792 		return;
793 
794 	skel->bss->in_test_mode = true;
795 
796 	err = bpf_iter_bpf_hash_map__load(skel);
797 	if (!ASSERT_OK(err, "bpf_iter_bpf_hash_map__load"))
798 		goto out;
799 
800 	/* iterator with hashmap2 and hashmap3 should fail */
801 	memset(&linfo, 0, sizeof(linfo));
802 	linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap2);
803 	opts.link_info = &linfo;
804 	opts.link_info_len = sizeof(linfo);
805 	link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
806 	if (!ASSERT_ERR_PTR(link, "attach_iter"))
807 		goto out;
808 
809 	linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap3);
810 	link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
811 	if (!ASSERT_ERR_PTR(link, "attach_iter"))
812 		goto out;
813 
814 	/* hashmap1 should be good, update map values here */
815 	map_fd = bpf_map__fd(skel->maps.hashmap1);
816 	for (i = 0; i < bpf_map__max_entries(skel->maps.hashmap1); i++) {
817 		key.a = i + 1;
818 		key.b = i + 2;
819 		key.c = i + 3;
820 		val = i + 4;
821 		expected_key_a += key.a;
822 		expected_key_b += key.b;
823 		expected_val += val;
824 
825 		err = bpf_map_update_elem(map_fd, &key, &val, BPF_ANY);
826 		if (!ASSERT_OK(err, "map_update"))
827 			goto out;
828 	}
829 
830 	/* Sleepable program is prohibited for hash map iterator */
831 	linfo.map.map_fd = map_fd;
832 	link = bpf_program__attach_iter(skel->progs.sleepable_dummy_dump, &opts);
833 	if (!ASSERT_ERR_PTR(link, "attach_sleepable_prog_to_iter"))
834 		goto out;
835 
836 	linfo.map.map_fd = map_fd;
837 	link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
838 	if (!ASSERT_OK_PTR(link, "attach_iter"))
839 		goto out;
840 
841 	iter_fd = bpf_iter_create(bpf_link__fd(link));
842 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
843 		goto free_link;
844 
845 	/* do some tests */
846 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
847 		;
848 	if (!ASSERT_GE(len, 0, "read"))
849 		goto close_iter;
850 
851 	/* test results */
852 	if (!ASSERT_EQ(skel->bss->key_sum_a, expected_key_a, "key_sum_a"))
853 		goto close_iter;
854 	if (!ASSERT_EQ(skel->bss->key_sum_b, expected_key_b, "key_sum_b"))
855 		goto close_iter;
856 	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
857 		goto close_iter;
858 
859 close_iter:
860 	close(iter_fd);
861 free_link:
862 	bpf_link__destroy(link);
863 out:
864 	bpf_iter_bpf_hash_map__destroy(skel);
865 }
866 
test_bpf_percpu_hash_map(void)867 static void test_bpf_percpu_hash_map(void)
868 {
869 	__u32 expected_key_a = 0, expected_key_b = 0;
870 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
871 	struct bpf_iter_bpf_percpu_hash_map *skel;
872 	int err, i, j, len, map_fd, iter_fd;
873 	union bpf_iter_link_info linfo;
874 	__u32 expected_val = 0;
875 	struct bpf_link *link;
876 	struct key_t {
877 		int a;
878 		int b;
879 		int c;
880 	} key;
881 	char buf[64];
882 	void *val;
883 
884 	skel = bpf_iter_bpf_percpu_hash_map__open();
885 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_hash_map__open"))
886 		return;
887 
888 	skel->rodata->num_cpus = bpf_num_possible_cpus();
889 	val = malloc(8 * bpf_num_possible_cpus());
890 	if (!ASSERT_OK_PTR(val, "malloc"))
891 		goto out;
892 
893 	err = bpf_iter_bpf_percpu_hash_map__load(skel);
894 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_hash_map__load"))
895 		goto out;
896 
897 	/* update map values here */
898 	map_fd = bpf_map__fd(skel->maps.hashmap1);
899 	for (i = 0; i < bpf_map__max_entries(skel->maps.hashmap1); i++) {
900 		key.a = i + 1;
901 		key.b = i + 2;
902 		key.c = i + 3;
903 		expected_key_a += key.a;
904 		expected_key_b += key.b;
905 
906 		for (j = 0; j < bpf_num_possible_cpus(); j++) {
907 			*(__u32 *)(val + j * 8) = i + j;
908 			expected_val += i + j;
909 		}
910 
911 		err = bpf_map_update_elem(map_fd, &key, val, BPF_ANY);
912 		if (!ASSERT_OK(err, "map_update"))
913 			goto out;
914 	}
915 
916 	memset(&linfo, 0, sizeof(linfo));
917 	linfo.map.map_fd = map_fd;
918 	opts.link_info = &linfo;
919 	opts.link_info_len = sizeof(linfo);
920 	link = bpf_program__attach_iter(skel->progs.dump_bpf_percpu_hash_map, &opts);
921 	if (!ASSERT_OK_PTR(link, "attach_iter"))
922 		goto out;
923 
924 	iter_fd = bpf_iter_create(bpf_link__fd(link));
925 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
926 		goto free_link;
927 
928 	/* do some tests */
929 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
930 		;
931 	if (!ASSERT_GE(len, 0, "read"))
932 		goto close_iter;
933 
934 	/* test results */
935 	if (!ASSERT_EQ(skel->bss->key_sum_a, expected_key_a, "key_sum_a"))
936 		goto close_iter;
937 	if (!ASSERT_EQ(skel->bss->key_sum_b, expected_key_b, "key_sum_b"))
938 		goto close_iter;
939 	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
940 		goto close_iter;
941 
942 close_iter:
943 	close(iter_fd);
944 free_link:
945 	bpf_link__destroy(link);
946 out:
947 	bpf_iter_bpf_percpu_hash_map__destroy(skel);
948 	free(val);
949 }
950 
test_bpf_array_map(void)951 static void test_bpf_array_map(void)
952 {
953 	__u64 val, expected_val = 0, res_first_val, first_val = 0;
954 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
955 	__u32 key, expected_key = 0, res_first_key;
956 	int err, i, map_fd, hash_fd, iter_fd;
957 	struct bpf_iter_bpf_array_map *skel;
958 	union bpf_iter_link_info linfo;
959 	struct bpf_link *link;
960 	char buf[64] = {};
961 	int len, start;
962 
963 	skel = bpf_iter_bpf_array_map__open_and_load();
964 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_array_map__open_and_load"))
965 		return;
966 
967 	map_fd = bpf_map__fd(skel->maps.arraymap1);
968 	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
969 		val = i + 4;
970 		expected_key += i;
971 		expected_val += val;
972 
973 		if (i == 0)
974 			first_val = val;
975 
976 		err = bpf_map_update_elem(map_fd, &i, &val, BPF_ANY);
977 		if (!ASSERT_OK(err, "map_update"))
978 			goto out;
979 	}
980 
981 	memset(&linfo, 0, sizeof(linfo));
982 	linfo.map.map_fd = map_fd;
983 	opts.link_info = &linfo;
984 	opts.link_info_len = sizeof(linfo);
985 	link = bpf_program__attach_iter(skel->progs.dump_bpf_array_map, &opts);
986 	if (!ASSERT_OK_PTR(link, "attach_iter"))
987 		goto out;
988 
989 	iter_fd = bpf_iter_create(bpf_link__fd(link));
990 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
991 		goto free_link;
992 
993 	/* do some tests */
994 	start = 0;
995 	while ((len = read(iter_fd, buf + start, sizeof(buf) - start)) > 0)
996 		start += len;
997 	if (!ASSERT_GE(len, 0, "read"))
998 		goto close_iter;
999 
1000 	/* test results */
1001 	res_first_key = *(__u32 *)buf;
1002 	res_first_val = *(__u64 *)(buf + sizeof(__u32));
1003 	if (!ASSERT_EQ(res_first_key, 0, "bpf_seq_write") ||
1004 			!ASSERT_EQ(res_first_val, first_val, "bpf_seq_write"))
1005 		goto close_iter;
1006 
1007 	if (!ASSERT_EQ(skel->bss->key_sum, expected_key, "key_sum"))
1008 		goto close_iter;
1009 	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
1010 		goto close_iter;
1011 
1012 	hash_fd = bpf_map__fd(skel->maps.hashmap1);
1013 	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
1014 		err = bpf_map_lookup_elem(map_fd, &i, &val);
1015 		if (!ASSERT_OK(err, "map_lookup arraymap1"))
1016 			goto close_iter;
1017 		if (!ASSERT_EQ(i, val, "invalid_val arraymap1"))
1018 			goto close_iter;
1019 
1020 		val = i + 4;
1021 		err = bpf_map_lookup_elem(hash_fd, &val, &key);
1022 		if (!ASSERT_OK(err, "map_lookup hashmap1"))
1023 			goto close_iter;
1024 		if (!ASSERT_EQ(key, val - 4, "invalid_val hashmap1"))
1025 			goto close_iter;
1026 	}
1027 
1028 close_iter:
1029 	close(iter_fd);
1030 free_link:
1031 	bpf_link__destroy(link);
1032 out:
1033 	bpf_iter_bpf_array_map__destroy(skel);
1034 }
1035 
test_bpf_array_map_iter_fd(void)1036 static void test_bpf_array_map_iter_fd(void)
1037 {
1038 	struct bpf_iter_bpf_array_map *skel;
1039 
1040 	skel = bpf_iter_bpf_array_map__open_and_load();
1041 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_array_map__open_and_load"))
1042 		return;
1043 
1044 	do_read_map_iter_fd(&skel->skeleton, skel->progs.dump_bpf_array_map,
1045 			    skel->maps.arraymap1);
1046 
1047 	bpf_iter_bpf_array_map__destroy(skel);
1048 }
1049 
test_bpf_percpu_array_map(void)1050 static void test_bpf_percpu_array_map(void)
1051 {
1052 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1053 	struct bpf_iter_bpf_percpu_array_map *skel;
1054 	__u32 expected_key = 0, expected_val = 0;
1055 	union bpf_iter_link_info linfo;
1056 	int err, i, j, map_fd, iter_fd;
1057 	struct bpf_link *link;
1058 	char buf[64];
1059 	void *val;
1060 	int len;
1061 
1062 	skel = bpf_iter_bpf_percpu_array_map__open();
1063 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_array_map__open"))
1064 		return;
1065 
1066 	skel->rodata->num_cpus = bpf_num_possible_cpus();
1067 	val = malloc(8 * bpf_num_possible_cpus());
1068 	if (!ASSERT_OK_PTR(val, "malloc"))
1069 		goto out;
1070 
1071 	err = bpf_iter_bpf_percpu_array_map__load(skel);
1072 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_percpu_array_map__load"))
1073 		goto out;
1074 
1075 	/* update map values here */
1076 	map_fd = bpf_map__fd(skel->maps.arraymap1);
1077 	for (i = 0; i < bpf_map__max_entries(skel->maps.arraymap1); i++) {
1078 		expected_key += i;
1079 
1080 		for (j = 0; j < bpf_num_possible_cpus(); j++) {
1081 			*(__u32 *)(val + j * 8) = i + j;
1082 			expected_val += i + j;
1083 		}
1084 
1085 		err = bpf_map_update_elem(map_fd, &i, val, BPF_ANY);
1086 		if (!ASSERT_OK(err, "map_update"))
1087 			goto out;
1088 	}
1089 
1090 	memset(&linfo, 0, sizeof(linfo));
1091 	linfo.map.map_fd = map_fd;
1092 	opts.link_info = &linfo;
1093 	opts.link_info_len = sizeof(linfo);
1094 	link = bpf_program__attach_iter(skel->progs.dump_bpf_percpu_array_map, &opts);
1095 	if (!ASSERT_OK_PTR(link, "attach_iter"))
1096 		goto out;
1097 
1098 	iter_fd = bpf_iter_create(bpf_link__fd(link));
1099 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
1100 		goto free_link;
1101 
1102 	/* do some tests */
1103 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
1104 		;
1105 	if (!ASSERT_GE(len, 0, "read"))
1106 		goto close_iter;
1107 
1108 	/* test results */
1109 	if (!ASSERT_EQ(skel->bss->key_sum, expected_key, "key_sum"))
1110 		goto close_iter;
1111 	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
1112 		goto close_iter;
1113 
1114 close_iter:
1115 	close(iter_fd);
1116 free_link:
1117 	bpf_link__destroy(link);
1118 out:
1119 	bpf_iter_bpf_percpu_array_map__destroy(skel);
1120 	free(val);
1121 }
1122 
1123 /* An iterator program deletes all local storage in a map. */
test_bpf_sk_storage_delete(void)1124 static void test_bpf_sk_storage_delete(void)
1125 {
1126 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1127 	struct bpf_iter_bpf_sk_storage_helpers *skel;
1128 	union bpf_iter_link_info linfo;
1129 	int err, len, map_fd, iter_fd;
1130 	struct bpf_link *link;
1131 	int sock_fd = -1;
1132 	__u32 val = 42;
1133 	char buf[64];
1134 
1135 	skel = bpf_iter_bpf_sk_storage_helpers__open_and_load();
1136 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_helpers__open_and_load"))
1137 		return;
1138 
1139 	map_fd = bpf_map__fd(skel->maps.sk_stg_map);
1140 
1141 	sock_fd = socket(AF_INET6, SOCK_STREAM, 0);
1142 	if (!ASSERT_GE(sock_fd, 0, "socket"))
1143 		goto out;
1144 
1145 	err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
1146 	if (!ASSERT_OK(err, "map_update"))
1147 		goto out;
1148 
1149 	memset(&linfo, 0, sizeof(linfo));
1150 	linfo.map.map_fd = map_fd;
1151 	opts.link_info = &linfo;
1152 	opts.link_info_len = sizeof(linfo);
1153 	link = bpf_program__attach_iter(skel->progs.delete_bpf_sk_storage_map,
1154 					&opts);
1155 	if (!ASSERT_OK_PTR(link, "attach_iter"))
1156 		goto out;
1157 
1158 	iter_fd = bpf_iter_create(bpf_link__fd(link));
1159 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
1160 		goto free_link;
1161 
1162 	/* do some tests */
1163 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
1164 		;
1165 	if (!ASSERT_GE(len, 0, "read"))
1166 		goto close_iter;
1167 
1168 	/* test results */
1169 	err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
1170 
1171 	 /* Note: The following assertions serve to ensure
1172 	  * the value was deleted. It does so by asserting
1173 	  * that bpf_map_lookup_elem has failed. This might
1174 	  * seem counterintuitive at first.
1175 	  */
1176 	ASSERT_ERR(err, "bpf_map_lookup_elem");
1177 	ASSERT_EQ(errno, ENOENT, "bpf_map_lookup_elem");
1178 
1179 close_iter:
1180 	close(iter_fd);
1181 free_link:
1182 	bpf_link__destroy(link);
1183 out:
1184 	if (sock_fd >= 0)
1185 		close(sock_fd);
1186 	bpf_iter_bpf_sk_storage_helpers__destroy(skel);
1187 }
1188 
1189 /* This creates a socket and its local storage. It then runs a task_iter BPF
1190  * program that replaces the existing socket local storage with the tgid of the
1191  * only task owning a file descriptor to this socket, this process, prog_tests.
1192  * It then runs a tcp socket iterator that negates the value in the existing
1193  * socket local storage, the test verifies that the resulting value is -pid.
1194  */
test_bpf_sk_storage_get(void)1195 static void test_bpf_sk_storage_get(void)
1196 {
1197 	struct bpf_iter_bpf_sk_storage_helpers *skel;
1198 	int err, map_fd, val = -1;
1199 	int sock_fd = -1;
1200 
1201 	skel = bpf_iter_bpf_sk_storage_helpers__open_and_load();
1202 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_helpers__open_and_load"))
1203 		return;
1204 
1205 	sock_fd = socket(AF_INET6, SOCK_STREAM, 0);
1206 	if (!ASSERT_GE(sock_fd, 0, "socket"))
1207 		goto out;
1208 
1209 	err = listen(sock_fd, 1);
1210 	if (!ASSERT_OK(err, "listen"))
1211 		goto close_socket;
1212 
1213 	map_fd = bpf_map__fd(skel->maps.sk_stg_map);
1214 
1215 	err = bpf_map_update_elem(map_fd, &sock_fd, &val, BPF_NOEXIST);
1216 	if (!ASSERT_OK(err, "bpf_map_update_elem"))
1217 		goto close_socket;
1218 
1219 	do_dummy_read(skel->progs.fill_socket_owner);
1220 
1221 	err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
1222 	if (!ASSERT_OK(err, "bpf_map_lookup_elem") ||
1223 			!ASSERT_EQ(val, getpid(), "bpf_map_lookup_elem"))
1224 		goto close_socket;
1225 
1226 	do_dummy_read(skel->progs.negate_socket_local_storage);
1227 
1228 	err = bpf_map_lookup_elem(map_fd, &sock_fd, &val);
1229 	ASSERT_OK(err, "bpf_map_lookup_elem");
1230 	ASSERT_EQ(val, -getpid(), "bpf_map_lookup_elem");
1231 
1232 close_socket:
1233 	close(sock_fd);
1234 out:
1235 	bpf_iter_bpf_sk_storage_helpers__destroy(skel);
1236 }
1237 
test_bpf_sk_storage_map_iter_fd(void)1238 static void test_bpf_sk_storage_map_iter_fd(void)
1239 {
1240 	struct bpf_iter_bpf_sk_storage_map *skel;
1241 
1242 	skel = bpf_iter_bpf_sk_storage_map__open_and_load();
1243 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_map__open_and_load"))
1244 		return;
1245 
1246 	do_read_map_iter_fd(&skel->skeleton, skel->progs.rw_bpf_sk_storage_map,
1247 			    skel->maps.sk_stg_map);
1248 
1249 	bpf_iter_bpf_sk_storage_map__destroy(skel);
1250 }
1251 
test_bpf_sk_storage_map(void)1252 static void test_bpf_sk_storage_map(void)
1253 {
1254 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1255 	int err, i, len, map_fd, iter_fd, num_sockets;
1256 	struct bpf_iter_bpf_sk_storage_map *skel;
1257 	union bpf_iter_link_info linfo;
1258 	int sock_fd[3] = {-1, -1, -1};
1259 	__u32 val, expected_val = 0;
1260 	struct bpf_link *link;
1261 	char buf[64];
1262 
1263 	skel = bpf_iter_bpf_sk_storage_map__open_and_load();
1264 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_sk_storage_map__open_and_load"))
1265 		return;
1266 
1267 	map_fd = bpf_map__fd(skel->maps.sk_stg_map);
1268 	num_sockets = ARRAY_SIZE(sock_fd);
1269 	for (i = 0; i < num_sockets; i++) {
1270 		sock_fd[i] = socket(AF_INET6, SOCK_STREAM, 0);
1271 		if (!ASSERT_GE(sock_fd[i], 0, "socket"))
1272 			goto out;
1273 
1274 		val = i + 1;
1275 		expected_val += val;
1276 
1277 		err = bpf_map_update_elem(map_fd, &sock_fd[i], &val,
1278 					  BPF_NOEXIST);
1279 		if (!ASSERT_OK(err, "map_update"))
1280 			goto out;
1281 	}
1282 
1283 	memset(&linfo, 0, sizeof(linfo));
1284 	linfo.map.map_fd = map_fd;
1285 	opts.link_info = &linfo;
1286 	opts.link_info_len = sizeof(linfo);
1287 	link = bpf_program__attach_iter(skel->progs.oob_write_bpf_sk_storage_map, &opts);
1288 	err = libbpf_get_error(link);
1289 	if (!ASSERT_EQ(err, -EACCES, "attach_oob_write_iter")) {
1290 		if (!err)
1291 			bpf_link__destroy(link);
1292 		goto out;
1293 	}
1294 
1295 	link = bpf_program__attach_iter(skel->progs.rw_bpf_sk_storage_map, &opts);
1296 	if (!ASSERT_OK_PTR(link, "attach_iter"))
1297 		goto out;
1298 
1299 	iter_fd = bpf_iter_create(bpf_link__fd(link));
1300 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
1301 		goto free_link;
1302 
1303 	skel->bss->to_add_val = time(NULL);
1304 	/* do some tests */
1305 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
1306 		;
1307 	if (!ASSERT_GE(len, 0, "read"))
1308 		goto close_iter;
1309 
1310 	/* test results */
1311 	if (!ASSERT_EQ(skel->bss->ipv6_sk_count, num_sockets, "ipv6_sk_count"))
1312 		goto close_iter;
1313 
1314 	if (!ASSERT_EQ(skel->bss->val_sum, expected_val, "val_sum"))
1315 		goto close_iter;
1316 
1317 	for (i = 0; i < num_sockets; i++) {
1318 		err = bpf_map_lookup_elem(map_fd, &sock_fd[i], &val);
1319 		if (!ASSERT_OK(err, "map_lookup") ||
1320 		    !ASSERT_EQ(val, i + 1 + skel->bss->to_add_val, "check_map_value"))
1321 			break;
1322 	}
1323 
1324 close_iter:
1325 	close(iter_fd);
1326 free_link:
1327 	bpf_link__destroy(link);
1328 out:
1329 	for (i = 0; i < num_sockets; i++) {
1330 		if (sock_fd[i] >= 0)
1331 			close(sock_fd[i]);
1332 	}
1333 	bpf_iter_bpf_sk_storage_map__destroy(skel);
1334 }
1335 
test_rdonly_buf_out_of_bound(void)1336 static void test_rdonly_buf_out_of_bound(void)
1337 {
1338 	DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1339 	struct bpf_iter_test_kern5 *skel;
1340 	union bpf_iter_link_info linfo;
1341 	struct bpf_link *link;
1342 
1343 	skel = bpf_iter_test_kern5__open_and_load();
1344 	if (!ASSERT_OK_PTR(skel, "bpf_iter_test_kern5__open_and_load"))
1345 		return;
1346 
1347 	memset(&linfo, 0, sizeof(linfo));
1348 	linfo.map.map_fd = bpf_map__fd(skel->maps.hashmap1);
1349 	opts.link_info = &linfo;
1350 	opts.link_info_len = sizeof(linfo);
1351 	link = bpf_program__attach_iter(skel->progs.dump_bpf_hash_map, &opts);
1352 	if (!ASSERT_ERR_PTR(link, "attach_iter"))
1353 		bpf_link__destroy(link);
1354 
1355 	bpf_iter_test_kern5__destroy(skel);
1356 }
1357 
test_buf_neg_offset(void)1358 static void test_buf_neg_offset(void)
1359 {
1360 	struct bpf_iter_test_kern6 *skel;
1361 
1362 	skel = bpf_iter_test_kern6__open_and_load();
1363 	if (!ASSERT_ERR_PTR(skel, "bpf_iter_test_kern6__open_and_load"))
1364 		bpf_iter_test_kern6__destroy(skel);
1365 }
1366 
test_link_iter(void)1367 static void test_link_iter(void)
1368 {
1369 	struct bpf_iter_bpf_link *skel;
1370 
1371 	skel = bpf_iter_bpf_link__open_and_load();
1372 	if (!ASSERT_OK_PTR(skel, "bpf_iter_bpf_link__open_and_load"))
1373 		return;
1374 
1375 	do_dummy_read(skel->progs.dump_bpf_link);
1376 
1377 	bpf_iter_bpf_link__destroy(skel);
1378 }
1379 
test_ksym_iter(void)1380 static void test_ksym_iter(void)
1381 {
1382 	struct bpf_iter_ksym *skel;
1383 
1384 	skel = bpf_iter_ksym__open_and_load();
1385 	if (!ASSERT_OK_PTR(skel, "bpf_iter_ksym__open_and_load"))
1386 		return;
1387 
1388 	do_dummy_read(skel->progs.dump_ksym);
1389 
1390 	bpf_iter_ksym__destroy(skel);
1391 }
1392 
1393 #define CMP_BUFFER_SIZE 1024
1394 static char task_vma_output[CMP_BUFFER_SIZE];
1395 static char proc_maps_output[CMP_BUFFER_SIZE];
1396 
1397 /* remove \0 and \t from str, and only keep the first line */
str_strip_first_line(char * str)1398 static void str_strip_first_line(char *str)
1399 {
1400 	char *dst = str, *src = str;
1401 
1402 	do {
1403 		if (*src == ' ' || *src == '\t')
1404 			src++;
1405 		else
1406 			*(dst++) = *(src++);
1407 
1408 	} while (*src != '\0' && *src != '\n');
1409 
1410 	*dst = '\0';
1411 }
1412 
test_task_vma_common(struct bpf_iter_attach_opts * opts)1413 static void test_task_vma_common(struct bpf_iter_attach_opts *opts)
1414 {
1415 	int err, iter_fd = -1, proc_maps_fd = -1;
1416 	struct bpf_iter_task_vmas *skel;
1417 	int len, read_size = 4;
1418 	char maps_path[64];
1419 
1420 	skel = bpf_iter_task_vmas__open();
1421 	if (!ASSERT_OK_PTR(skel, "bpf_iter_task_vmas__open"))
1422 		return;
1423 
1424 	skel->bss->pid = getpid();
1425 	skel->bss->one_task = opts ? 1 : 0;
1426 
1427 	err = bpf_iter_task_vmas__load(skel);
1428 	if (!ASSERT_OK(err, "bpf_iter_task_vmas__load"))
1429 		goto out;
1430 
1431 	skel->links.proc_maps = bpf_program__attach_iter(
1432 		skel->progs.proc_maps, opts);
1433 
1434 	if (!ASSERT_OK_PTR(skel->links.proc_maps, "bpf_program__attach_iter")) {
1435 		skel->links.proc_maps = NULL;
1436 		goto out;
1437 	}
1438 
1439 	iter_fd = bpf_iter_create(bpf_link__fd(skel->links.proc_maps));
1440 	if (!ASSERT_GE(iter_fd, 0, "create_iter"))
1441 		goto out;
1442 
1443 	/* Read CMP_BUFFER_SIZE (1kB) from bpf_iter. Read in small chunks
1444 	 * to trigger seq_file corner cases.
1445 	 */
1446 	len = 0;
1447 	while (len < CMP_BUFFER_SIZE) {
1448 		err = read_fd_into_buffer(iter_fd, task_vma_output + len,
1449 					  MIN(read_size, CMP_BUFFER_SIZE - len));
1450 		if (!err)
1451 			break;
1452 		if (!ASSERT_GE(err, 0, "read_iter_fd"))
1453 			goto out;
1454 		len += err;
1455 	}
1456 	if (opts)
1457 		ASSERT_EQ(skel->bss->one_task_error, 0, "unexpected task");
1458 
1459 	/* read CMP_BUFFER_SIZE (1kB) from /proc/pid/maps */
1460 	snprintf(maps_path, 64, "/proc/%u/maps", skel->bss->pid);
1461 	proc_maps_fd = open(maps_path, O_RDONLY);
1462 	if (!ASSERT_GE(proc_maps_fd, 0, "open_proc_maps"))
1463 		goto out;
1464 	err = read_fd_into_buffer(proc_maps_fd, proc_maps_output, CMP_BUFFER_SIZE);
1465 	if (!ASSERT_GE(err, 0, "read_prog_maps_fd"))
1466 		goto out;
1467 
1468 	/* strip and compare the first line of the two files */
1469 	str_strip_first_line(task_vma_output);
1470 	str_strip_first_line(proc_maps_output);
1471 
1472 	ASSERT_STREQ(task_vma_output, proc_maps_output, "compare_output");
1473 
1474 	check_bpf_link_info(skel->progs.proc_maps);
1475 
1476 out:
1477 	close(proc_maps_fd);
1478 	close(iter_fd);
1479 	bpf_iter_task_vmas__destroy(skel);
1480 }
1481 
test_task_vma_dead_task(void)1482 static void test_task_vma_dead_task(void)
1483 {
1484 	struct bpf_iter_task_vmas *skel;
1485 	int wstatus, child_pid = -1;
1486 	time_t start_tm, cur_tm;
1487 	int err, iter_fd = -1;
1488 	int wait_sec = 3;
1489 
1490 	skel = bpf_iter_task_vmas__open();
1491 	if (!ASSERT_OK_PTR(skel, "bpf_iter_task_vmas__open"))
1492 		return;
1493 
1494 	skel->bss->pid = getpid();
1495 
1496 	err = bpf_iter_task_vmas__load(skel);
1497 	if (!ASSERT_OK(err, "bpf_iter_task_vmas__load"))
1498 		goto out;
1499 
1500 	skel->links.proc_maps = bpf_program__attach_iter(
1501 		skel->progs.proc_maps, NULL);
1502 
1503 	if (!ASSERT_OK_PTR(skel->links.proc_maps, "bpf_program__attach_iter")) {
1504 		skel->links.proc_maps = NULL;
1505 		goto out;
1506 	}
1507 
1508 	start_tm = time(NULL);
1509 	cur_tm = start_tm;
1510 
1511 	child_pid = fork();
1512 	if (child_pid == 0) {
1513 		/* Fork short-lived processes in the background. */
1514 		while (cur_tm < start_tm + wait_sec) {
1515 			system("echo > /dev/null");
1516 			cur_tm = time(NULL);
1517 		}
1518 		exit(0);
1519 	}
1520 
1521 	if (!ASSERT_GE(child_pid, 0, "fork_child"))
1522 		goto out;
1523 
1524 	while (cur_tm < start_tm + wait_sec) {
1525 		iter_fd = bpf_iter_create(bpf_link__fd(skel->links.proc_maps));
1526 		if (!ASSERT_GE(iter_fd, 0, "create_iter"))
1527 			goto out;
1528 
1529 		/* Drain all data from iter_fd. */
1530 		while (cur_tm < start_tm + wait_sec) {
1531 			err = read_fd_into_buffer(iter_fd, task_vma_output, CMP_BUFFER_SIZE);
1532 			if (!ASSERT_GE(err, 0, "read_iter_fd"))
1533 				goto out;
1534 
1535 			cur_tm = time(NULL);
1536 
1537 			if (err == 0)
1538 				break;
1539 		}
1540 
1541 		close(iter_fd);
1542 		iter_fd = -1;
1543 	}
1544 
1545 	check_bpf_link_info(skel->progs.proc_maps);
1546 
1547 out:
1548 	waitpid(child_pid, &wstatus, 0);
1549 	close(iter_fd);
1550 	bpf_iter_task_vmas__destroy(skel);
1551 }
1552 
test_bpf_sockmap_map_iter_fd(void)1553 void test_bpf_sockmap_map_iter_fd(void)
1554 {
1555 	struct bpf_iter_sockmap *skel;
1556 
1557 	skel = bpf_iter_sockmap__open_and_load();
1558 	if (!ASSERT_OK_PTR(skel, "bpf_iter_sockmap__open_and_load"))
1559 		return;
1560 
1561 	do_read_map_iter_fd(&skel->skeleton, skel->progs.copy, skel->maps.sockmap);
1562 
1563 	bpf_iter_sockmap__destroy(skel);
1564 }
1565 
test_task_vma(void)1566 static void test_task_vma(void)
1567 {
1568 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1569 	union bpf_iter_link_info linfo;
1570 
1571 	memset(&linfo, 0, sizeof(linfo));
1572 	linfo.task.tid = getpid();
1573 	opts.link_info = &linfo;
1574 	opts.link_info_len = sizeof(linfo);
1575 
1576 	test_task_vma_common(&opts);
1577 	test_task_vma_common(NULL);
1578 }
1579 
1580 /* uprobe attach point */
trigger_func(int arg)1581 static noinline int trigger_func(int arg)
1582 {
1583 	asm volatile ("");
1584 	return arg + 1;
1585 }
1586 
test_task_vma_offset_common(struct bpf_iter_attach_opts * opts,bool one_proc)1587 static void test_task_vma_offset_common(struct bpf_iter_attach_opts *opts, bool one_proc)
1588 {
1589 	struct bpf_iter_vma_offset *skel;
1590 	char buf[16] = {};
1591 	int iter_fd, len;
1592 	int pgsz, shift;
1593 
1594 	skel = bpf_iter_vma_offset__open_and_load();
1595 	if (!ASSERT_OK_PTR(skel, "bpf_iter_vma_offset__open_and_load"))
1596 		return;
1597 
1598 	skel->bss->pid = getpid();
1599 	skel->bss->address = (uintptr_t)trigger_func;
1600 	for (pgsz = getpagesize(), shift = 0; pgsz > 1; pgsz >>= 1, shift++)
1601 		;
1602 	skel->bss->page_shift = shift;
1603 
1604 	skel->links.get_vma_offset = bpf_program__attach_iter(skel->progs.get_vma_offset, opts);
1605 	if (!ASSERT_OK_PTR(skel->links.get_vma_offset, "attach_iter"))
1606 		goto exit;
1607 
1608 	iter_fd = bpf_iter_create(bpf_link__fd(skel->links.get_vma_offset));
1609 	if (!ASSERT_GT(iter_fd, 0, "create_iter"))
1610 		goto exit;
1611 
1612 	while ((len = read(iter_fd, buf, sizeof(buf))) > 0)
1613 		;
1614 	buf[15] = 0;
1615 	ASSERT_EQ(strcmp(buf, "OK\n"), 0, "strcmp");
1616 
1617 	ASSERT_EQ(skel->bss->offset, get_uprobe_offset(trigger_func), "offset");
1618 	if (one_proc)
1619 		ASSERT_EQ(skel->bss->unique_tgid_cnt, 1, "unique_tgid_count");
1620 	else
1621 		ASSERT_GT(skel->bss->unique_tgid_cnt, 1, "unique_tgid_count");
1622 
1623 	close(iter_fd);
1624 
1625 exit:
1626 	bpf_iter_vma_offset__destroy(skel);
1627 }
1628 
test_task_vma_offset(void)1629 static void test_task_vma_offset(void)
1630 {
1631 	LIBBPF_OPTS(bpf_iter_attach_opts, opts);
1632 	union bpf_iter_link_info linfo;
1633 
1634 	memset(&linfo, 0, sizeof(linfo));
1635 	linfo.task.pid = getpid();
1636 	opts.link_info = &linfo;
1637 	opts.link_info_len = sizeof(linfo);
1638 
1639 	test_task_vma_offset_common(&opts, true);
1640 
1641 	linfo.task.pid = 0;
1642 	linfo.task.tid = getpid();
1643 	test_task_vma_offset_common(&opts, true);
1644 
1645 	test_task_vma_offset_common(NULL, false);
1646 }
1647 
test_bpf_iter(void)1648 void test_bpf_iter(void)
1649 {
1650 	ASSERT_OK(pthread_mutex_init(&do_nothing_mutex, NULL), "pthread_mutex_init");
1651 
1652 	if (test__start_subtest("btf_id_or_null"))
1653 		test_btf_id_or_null();
1654 	if (test__start_subtest("ipv6_route"))
1655 		test_ipv6_route();
1656 	if (test__start_subtest("netlink"))
1657 		test_netlink();
1658 	if (test__start_subtest("bpf_map"))
1659 		test_bpf_map();
1660 	if (test__start_subtest("task_tid"))
1661 		test_task_tid();
1662 	if (test__start_subtest("task_pid"))
1663 		test_task_pid();
1664 	if (test__start_subtest("task_pidfd"))
1665 		test_task_pidfd();
1666 	if (test__start_subtest("task_sleepable"))
1667 		test_task_sleepable();
1668 	if (test__start_subtest("task_stack"))
1669 		test_task_stack();
1670 	if (test__start_subtest("task_file"))
1671 		test_task_file();
1672 	if (test__start_subtest("task_vma"))
1673 		test_task_vma();
1674 	if (test__start_subtest("task_vma_dead_task"))
1675 		test_task_vma_dead_task();
1676 	if (test__start_subtest("task_btf"))
1677 		test_task_btf();
1678 	if (test__start_subtest("tcp4"))
1679 		test_tcp4();
1680 	if (test__start_subtest("tcp6"))
1681 		test_tcp6();
1682 	if (test__start_subtest("udp4"))
1683 		test_udp4();
1684 	if (test__start_subtest("udp6"))
1685 		test_udp6();
1686 	if (test__start_subtest("unix"))
1687 		test_unix();
1688 	if (test__start_subtest("anon"))
1689 		test_anon_iter(false);
1690 	if (test__start_subtest("anon-read-one-char"))
1691 		test_anon_iter(true);
1692 	if (test__start_subtest("file"))
1693 		test_file_iter();
1694 	if (test__start_subtest("overflow"))
1695 		test_overflow(false, false);
1696 	if (test__start_subtest("overflow-e2big"))
1697 		test_overflow(true, false);
1698 	if (test__start_subtest("prog-ret-1"))
1699 		test_overflow(false, true);
1700 	if (test__start_subtest("bpf_hash_map"))
1701 		test_bpf_hash_map();
1702 	if (test__start_subtest("bpf_percpu_hash_map"))
1703 		test_bpf_percpu_hash_map();
1704 	if (test__start_subtest("bpf_array_map"))
1705 		test_bpf_array_map();
1706 	if (test__start_subtest("bpf_array_map_iter_fd"))
1707 		test_bpf_array_map_iter_fd();
1708 	if (test__start_subtest("bpf_percpu_array_map"))
1709 		test_bpf_percpu_array_map();
1710 	if (test__start_subtest("bpf_sk_storage_map"))
1711 		test_bpf_sk_storage_map();
1712 	if (test__start_subtest("bpf_sk_storage_map_iter_fd"))
1713 		test_bpf_sk_storage_map_iter_fd();
1714 	if (test__start_subtest("bpf_sk_storage_delete"))
1715 		test_bpf_sk_storage_delete();
1716 	if (test__start_subtest("bpf_sk_storage_get"))
1717 		test_bpf_sk_storage_get();
1718 	if (test__start_subtest("rdonly-buf-out-of-bound"))
1719 		test_rdonly_buf_out_of_bound();
1720 	if (test__start_subtest("buf-neg-offset"))
1721 		test_buf_neg_offset();
1722 	if (test__start_subtest("link-iter"))
1723 		test_link_iter();
1724 	if (test__start_subtest("ksym"))
1725 		test_ksym_iter();
1726 	if (test__start_subtest("bpf_sockmap_map_iter_fd"))
1727 		test_bpf_sockmap_map_iter_fd();
1728 	if (test__start_subtest("vma_offset"))
1729 		test_task_vma_offset();
1730 }
1731