1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2017 Facebook
3  */
4 #define _GNU_SOURCE
5 #include "test_progs.h"
6 #include "cgroup_helpers.h"
7 #include "bpf_rlimit.h"
8 #include <argp.h>
9 #include <pthread.h>
10 #include <sched.h>
11 #include <signal.h>
12 #include <string.h>
13 #include <execinfo.h> /* backtrace */
14 #include <linux/membarrier.h>
15 
16 /* Adapted from perf/util/string.c */
17 static bool glob_match(const char *str, const char *pat)
18 {
19 	while (*str && *pat && *pat != '*') {
20 		if (*str != *pat)
21 			return false;
22 		str++;
23 		pat++;
24 	}
25 	/* Check wild card */
26 	if (*pat == '*') {
27 		while (*pat == '*')
28 			pat++;
29 		if (!*pat) /* Tail wild card matches all */
30 			return true;
31 		while (*str)
32 			if (glob_match(str++, pat))
33 				return true;
34 	}
35 	return !*str && !*pat;
36 }
37 
38 #define EXIT_NO_TEST		2
39 #define EXIT_ERR_SETUP_INFRA	3
40 
41 /* defined in test_progs.h */
42 struct test_env env = {};
43 
44 struct prog_test_def {
45 	const char *test_name;
46 	int test_num;
47 	void (*run_test)(void);
48 	bool force_log;
49 	int error_cnt;
50 	int skip_cnt;
51 	bool tested;
52 	bool need_cgroup_cleanup;
53 
54 	char *subtest_name;
55 	int subtest_num;
56 
57 	/* store counts before subtest started */
58 	int old_error_cnt;
59 };
60 
61 /* Override C runtime library's usleep() implementation to ensure nanosleep()
62  * is always called. Usleep is frequently used in selftests as a way to
63  * trigger kprobe and tracepoints.
64  */
65 int usleep(useconds_t usec)
66 {
67 	struct timespec ts = {
68 		.tv_sec = usec / 1000000,
69 		.tv_nsec = (usec % 1000000) * 1000,
70 	};
71 
72 	return syscall(__NR_nanosleep, &ts, NULL);
73 }
74 
75 static bool should_run(struct test_selector *sel, int num, const char *name)
76 {
77 	int i;
78 
79 	for (i = 0; i < sel->blacklist.cnt; i++) {
80 		if (glob_match(name, sel->blacklist.strs[i]))
81 			return false;
82 	}
83 
84 	for (i = 0; i < sel->whitelist.cnt; i++) {
85 		if (glob_match(name, sel->whitelist.strs[i]))
86 			return true;
87 	}
88 
89 	if (!sel->whitelist.cnt && !sel->num_set)
90 		return true;
91 
92 	return num < sel->num_set_len && sel->num_set[num];
93 }
94 
95 static void dump_test_log(const struct prog_test_def *test, bool failed)
96 {
97 	if (stdout == env.stdout)
98 		return;
99 
100 	fflush(stdout); /* exports env.log_buf & env.log_cnt */
101 
102 	if (env.verbosity > VERBOSE_NONE || test->force_log || failed) {
103 		if (env.log_cnt) {
104 			env.log_buf[env.log_cnt] = '\0';
105 			fprintf(env.stdout, "%s", env.log_buf);
106 			if (env.log_buf[env.log_cnt - 1] != '\n')
107 				fprintf(env.stdout, "\n");
108 		}
109 	}
110 
111 	fseeko(stdout, 0, SEEK_SET); /* rewind */
112 }
113 
114 static void skip_account(void)
115 {
116 	if (env.test->skip_cnt) {
117 		env.skip_cnt++;
118 		env.test->skip_cnt = 0;
119 	}
120 }
121 
122 static void stdio_restore(void);
123 
124 /* A bunch of tests set custom affinity per-thread and/or per-process. Reset
125  * it after each test/sub-test.
126  */
127 static void reset_affinity() {
128 
129 	cpu_set_t cpuset;
130 	int i, err;
131 
132 	CPU_ZERO(&cpuset);
133 	for (i = 0; i < env.nr_cpus; i++)
134 		CPU_SET(i, &cpuset);
135 
136 	err = sched_setaffinity(0, sizeof(cpuset), &cpuset);
137 	if (err < 0) {
138 		stdio_restore();
139 		fprintf(stderr, "Failed to reset process affinity: %d!\n", err);
140 		exit(EXIT_ERR_SETUP_INFRA);
141 	}
142 	err = pthread_setaffinity_np(pthread_self(), sizeof(cpuset), &cpuset);
143 	if (err < 0) {
144 		stdio_restore();
145 		fprintf(stderr, "Failed to reset thread affinity: %d!\n", err);
146 		exit(EXIT_ERR_SETUP_INFRA);
147 	}
148 }
149 
150 static void save_netns(void)
151 {
152 	env.saved_netns_fd = open("/proc/self/ns/net", O_RDONLY);
153 	if (env.saved_netns_fd == -1) {
154 		perror("open(/proc/self/ns/net)");
155 		exit(EXIT_ERR_SETUP_INFRA);
156 	}
157 }
158 
159 static void restore_netns(void)
160 {
161 	if (setns(env.saved_netns_fd, CLONE_NEWNET) == -1) {
162 		stdio_restore();
163 		perror("setns(CLONE_NEWNS)");
164 		exit(EXIT_ERR_SETUP_INFRA);
165 	}
166 }
167 
168 void test__end_subtest()
169 {
170 	struct prog_test_def *test = env.test;
171 	int sub_error_cnt = test->error_cnt - test->old_error_cnt;
172 
173 	dump_test_log(test, sub_error_cnt);
174 
175 	fprintf(env.stdout, "#%d/%d %s/%s:%s\n",
176 	       test->test_num, test->subtest_num, test->test_name, test->subtest_name,
177 	       sub_error_cnt ? "FAIL" : (test->skip_cnt ? "SKIP" : "OK"));
178 
179 	if (sub_error_cnt)
180 		env.fail_cnt++;
181 	else if (test->skip_cnt == 0)
182 		env.sub_succ_cnt++;
183 	skip_account();
184 
185 	free(test->subtest_name);
186 	test->subtest_name = NULL;
187 }
188 
189 bool test__start_subtest(const char *name)
190 {
191 	struct prog_test_def *test = env.test;
192 
193 	if (test->subtest_name)
194 		test__end_subtest();
195 
196 	test->subtest_num++;
197 
198 	if (!name || !name[0]) {
199 		fprintf(env.stderr,
200 			"Subtest #%d didn't provide sub-test name!\n",
201 			test->subtest_num);
202 		return false;
203 	}
204 
205 	if (!should_run(&env.subtest_selector, test->subtest_num, name))
206 		return false;
207 
208 	test->subtest_name = strdup(name);
209 	if (!test->subtest_name) {
210 		fprintf(env.stderr,
211 			"Subtest #%d: failed to copy subtest name!\n",
212 			test->subtest_num);
213 		return false;
214 	}
215 	env.test->old_error_cnt = env.test->error_cnt;
216 
217 	return true;
218 }
219 
220 void test__force_log() {
221 	env.test->force_log = true;
222 }
223 
224 void test__skip(void)
225 {
226 	env.test->skip_cnt++;
227 }
228 
229 void test__fail(void)
230 {
231 	env.test->error_cnt++;
232 }
233 
234 int test__join_cgroup(const char *path)
235 {
236 	int fd;
237 
238 	if (!env.test->need_cgroup_cleanup) {
239 		if (setup_cgroup_environment()) {
240 			fprintf(stderr,
241 				"#%d %s: Failed to setup cgroup environment\n",
242 				env.test->test_num, env.test->test_name);
243 			return -1;
244 		}
245 
246 		env.test->need_cgroup_cleanup = true;
247 	}
248 
249 	fd = create_and_get_cgroup(path);
250 	if (fd < 0) {
251 		fprintf(stderr,
252 			"#%d %s: Failed to create cgroup '%s' (errno=%d)\n",
253 			env.test->test_num, env.test->test_name, path, errno);
254 		return fd;
255 	}
256 
257 	if (join_cgroup(path)) {
258 		fprintf(stderr,
259 			"#%d %s: Failed to join cgroup '%s' (errno=%d)\n",
260 			env.test->test_num, env.test->test_name, path, errno);
261 		return -1;
262 	}
263 
264 	return fd;
265 }
266 
267 int bpf_find_map(const char *test, struct bpf_object *obj, const char *name)
268 {
269 	struct bpf_map *map;
270 
271 	map = bpf_object__find_map_by_name(obj, name);
272 	if (!map) {
273 		fprintf(stdout, "%s:FAIL:map '%s' not found\n", test, name);
274 		test__fail();
275 		return -1;
276 	}
277 	return bpf_map__fd(map);
278 }
279 
280 static bool is_jit_enabled(void)
281 {
282 	const char *jit_sysctl = "/proc/sys/net/core/bpf_jit_enable";
283 	bool enabled = false;
284 	int sysctl_fd;
285 
286 	sysctl_fd = open(jit_sysctl, 0, O_RDONLY);
287 	if (sysctl_fd != -1) {
288 		char tmpc;
289 
290 		if (read(sysctl_fd, &tmpc, sizeof(tmpc)) == 1)
291 			enabled = (tmpc != '0');
292 		close(sysctl_fd);
293 	}
294 
295 	return enabled;
296 }
297 
298 int compare_map_keys(int map1_fd, int map2_fd)
299 {
300 	__u32 key, next_key;
301 	char val_buf[PERF_MAX_STACK_DEPTH *
302 		     sizeof(struct bpf_stack_build_id)];
303 	int err;
304 
305 	err = bpf_map_get_next_key(map1_fd, NULL, &key);
306 	if (err)
307 		return err;
308 	err = bpf_map_lookup_elem(map2_fd, &key, val_buf);
309 	if (err)
310 		return err;
311 
312 	while (bpf_map_get_next_key(map1_fd, &key, &next_key) == 0) {
313 		err = bpf_map_lookup_elem(map2_fd, &next_key, val_buf);
314 		if (err)
315 			return err;
316 
317 		key = next_key;
318 	}
319 	if (errno != ENOENT)
320 		return -1;
321 
322 	return 0;
323 }
324 
325 int compare_stack_ips(int smap_fd, int amap_fd, int stack_trace_len)
326 {
327 	__u32 key, next_key, *cur_key_p, *next_key_p;
328 	char *val_buf1, *val_buf2;
329 	int i, err = 0;
330 
331 	val_buf1 = malloc(stack_trace_len);
332 	val_buf2 = malloc(stack_trace_len);
333 	cur_key_p = NULL;
334 	next_key_p = &key;
335 	while (bpf_map_get_next_key(smap_fd, cur_key_p, next_key_p) == 0) {
336 		err = bpf_map_lookup_elem(smap_fd, next_key_p, val_buf1);
337 		if (err)
338 			goto out;
339 		err = bpf_map_lookup_elem(amap_fd, next_key_p, val_buf2);
340 		if (err)
341 			goto out;
342 		for (i = 0; i < stack_trace_len; i++) {
343 			if (val_buf1[i] != val_buf2[i]) {
344 				err = -1;
345 				goto out;
346 			}
347 		}
348 		key = *next_key_p;
349 		cur_key_p = &key;
350 		next_key_p = &next_key;
351 	}
352 	if (errno != ENOENT)
353 		err = -1;
354 
355 out:
356 	free(val_buf1);
357 	free(val_buf2);
358 	return err;
359 }
360 
361 int extract_build_id(char *build_id, size_t size)
362 {
363 	FILE *fp;
364 	char *line = NULL;
365 	size_t len = 0;
366 
367 	fp = popen("readelf -n ./urandom_read | grep 'Build ID'", "r");
368 	if (fp == NULL)
369 		return -1;
370 
371 	if (getline(&line, &len, fp) == -1)
372 		goto err;
373 	fclose(fp);
374 
375 	if (len > size)
376 		len = size;
377 	memcpy(build_id, line, len);
378 	build_id[len] = '\0';
379 	free(line);
380 	return 0;
381 err:
382 	fclose(fp);
383 	return -1;
384 }
385 
386 static int finit_module(int fd, const char *param_values, int flags)
387 {
388 	return syscall(__NR_finit_module, fd, param_values, flags);
389 }
390 
391 static int delete_module(const char *name, int flags)
392 {
393 	return syscall(__NR_delete_module, name, flags);
394 }
395 
396 /*
397  * Trigger synchronize_rcu() in kernel.
398  */
399 int kern_sync_rcu(void)
400 {
401 	return syscall(__NR_membarrier, MEMBARRIER_CMD_SHARED, 0, 0);
402 }
403 
404 static void unload_bpf_testmod(void)
405 {
406 	if (kern_sync_rcu())
407 		fprintf(env.stderr, "Failed to trigger kernel-side RCU sync!\n");
408 	if (delete_module("bpf_testmod", 0)) {
409 		if (errno == ENOENT) {
410 			if (env.verbosity > VERBOSE_NONE)
411 				fprintf(stdout, "bpf_testmod.ko is already unloaded.\n");
412 			return;
413 		}
414 		fprintf(env.stderr, "Failed to unload bpf_testmod.ko from kernel: %d\n", -errno);
415 		return;
416 	}
417 	if (env.verbosity > VERBOSE_NONE)
418 		fprintf(stdout, "Successfully unloaded bpf_testmod.ko.\n");
419 }
420 
421 static int load_bpf_testmod(void)
422 {
423 	int fd;
424 
425 	/* ensure previous instance of the module is unloaded */
426 	unload_bpf_testmod();
427 
428 	if (env.verbosity > VERBOSE_NONE)
429 		fprintf(stdout, "Loading bpf_testmod.ko...\n");
430 
431 	fd = open("bpf_testmod.ko", O_RDONLY);
432 	if (fd < 0) {
433 		fprintf(env.stderr, "Can't find bpf_testmod.ko kernel module: %d\n", -errno);
434 		return -ENOENT;
435 	}
436 	if (finit_module(fd, "", 0)) {
437 		fprintf(env.stderr, "Failed to load bpf_testmod.ko into the kernel: %d\n", -errno);
438 		close(fd);
439 		return -EINVAL;
440 	}
441 	close(fd);
442 
443 	if (env.verbosity > VERBOSE_NONE)
444 		fprintf(stdout, "Successfully loaded bpf_testmod.ko.\n");
445 	return 0;
446 }
447 
448 /* extern declarations for test funcs */
449 #define DEFINE_TEST(name) extern void test_##name(void);
450 #include <prog_tests/tests.h>
451 #undef DEFINE_TEST
452 
453 static struct prog_test_def prog_test_defs[] = {
454 #define DEFINE_TEST(name) {		\
455 	.test_name = #name,		\
456 	.run_test = &test_##name,	\
457 },
458 #include <prog_tests/tests.h>
459 #undef DEFINE_TEST
460 };
461 const int prog_test_cnt = ARRAY_SIZE(prog_test_defs);
462 
463 const char *argp_program_version = "test_progs 0.1";
464 const char *argp_program_bug_address = "<bpf@vger.kernel.org>";
465 const char argp_program_doc[] = "BPF selftests test runner";
466 
467 enum ARG_KEYS {
468 	ARG_TEST_NUM = 'n',
469 	ARG_TEST_NAME = 't',
470 	ARG_TEST_NAME_BLACKLIST = 'b',
471 	ARG_VERIFIER_STATS = 's',
472 	ARG_VERBOSE = 'v',
473 	ARG_GET_TEST_CNT = 'c',
474 	ARG_LIST_TEST_NAMES = 'l',
475 	ARG_TEST_NAME_GLOB_ALLOWLIST = 'a',
476 	ARG_TEST_NAME_GLOB_DENYLIST = 'd',
477 };
478 
479 static const struct argp_option opts[] = {
480 	{ "num", ARG_TEST_NUM, "NUM", 0,
481 	  "Run test number NUM only " },
482 	{ "name", ARG_TEST_NAME, "NAMES", 0,
483 	  "Run tests with names containing any string from NAMES list" },
484 	{ "name-blacklist", ARG_TEST_NAME_BLACKLIST, "NAMES", 0,
485 	  "Don't run tests with names containing any string from NAMES list" },
486 	{ "verifier-stats", ARG_VERIFIER_STATS, NULL, 0,
487 	  "Output verifier statistics", },
488 	{ "verbose", ARG_VERBOSE, "LEVEL", OPTION_ARG_OPTIONAL,
489 	  "Verbose output (use -vv or -vvv for progressively verbose output)" },
490 	{ "count", ARG_GET_TEST_CNT, NULL, 0,
491 	  "Get number of selected top-level tests " },
492 	{ "list", ARG_LIST_TEST_NAMES, NULL, 0,
493 	  "List test names that would run (without running them) " },
494 	{ "allow", ARG_TEST_NAME_GLOB_ALLOWLIST, "NAMES", 0,
495 	  "Run tests with name matching the pattern (supports '*' wildcard)." },
496 	{ "deny", ARG_TEST_NAME_GLOB_DENYLIST, "NAMES", 0,
497 	  "Don't run tests with name matching the pattern (supports '*' wildcard)." },
498 	{},
499 };
500 
501 static int libbpf_print_fn(enum libbpf_print_level level,
502 			   const char *format, va_list args)
503 {
504 	if (env.verbosity < VERBOSE_VERY && level == LIBBPF_DEBUG)
505 		return 0;
506 	vfprintf(stdout, format, args);
507 	return 0;
508 }
509 
510 static void free_str_set(const struct str_set *set)
511 {
512 	int i;
513 
514 	if (!set)
515 		return;
516 
517 	for (i = 0; i < set->cnt; i++)
518 		free((void *)set->strs[i]);
519 	free(set->strs);
520 }
521 
522 static int parse_str_list(const char *s, struct str_set *set, bool is_glob_pattern)
523 {
524 	char *input, *state = NULL, *next, **tmp, **strs = NULL;
525 	int i, cnt = 0;
526 
527 	input = strdup(s);
528 	if (!input)
529 		return -ENOMEM;
530 
531 	while ((next = strtok_r(state ? NULL : input, ",", &state))) {
532 		tmp = realloc(strs, sizeof(*strs) * (cnt + 1));
533 		if (!tmp)
534 			goto err;
535 		strs = tmp;
536 
537 		if (is_glob_pattern) {
538 			strs[cnt] = strdup(next);
539 			if (!strs[cnt])
540 				goto err;
541 		} else {
542 			strs[cnt] = malloc(strlen(next) + 2 + 1);
543 			if (!strs[cnt])
544 				goto err;
545 			sprintf(strs[cnt], "*%s*", next);
546 		}
547 
548 		cnt++;
549 	}
550 
551 	tmp = realloc(set->strs, sizeof(*strs) * (cnt + set->cnt));
552 	if (!tmp)
553 		goto err;
554 	memcpy(tmp + set->cnt, strs, sizeof(*strs) * cnt);
555 	set->strs = (const char **)tmp;
556 	set->cnt += cnt;
557 
558 	free(input);
559 	free(strs);
560 	return 0;
561 err:
562 	for (i = 0; i < cnt; i++)
563 		free(strs[i]);
564 	free(strs);
565 	free(input);
566 	return -ENOMEM;
567 }
568 
569 extern int extra_prog_load_log_flags;
570 
571 static error_t parse_arg(int key, char *arg, struct argp_state *state)
572 {
573 	struct test_env *env = state->input;
574 
575 	switch (key) {
576 	case ARG_TEST_NUM: {
577 		char *subtest_str = strchr(arg, '/');
578 
579 		if (subtest_str) {
580 			*subtest_str = '\0';
581 			if (parse_num_list(subtest_str + 1,
582 					   &env->subtest_selector.num_set,
583 					   &env->subtest_selector.num_set_len)) {
584 				fprintf(stderr,
585 					"Failed to parse subtest numbers.\n");
586 				return -EINVAL;
587 			}
588 		}
589 		if (parse_num_list(arg, &env->test_selector.num_set,
590 				   &env->test_selector.num_set_len)) {
591 			fprintf(stderr, "Failed to parse test numbers.\n");
592 			return -EINVAL;
593 		}
594 		break;
595 	}
596 	case ARG_TEST_NAME_GLOB_ALLOWLIST:
597 	case ARG_TEST_NAME: {
598 		char *subtest_str = strchr(arg, '/');
599 
600 		if (subtest_str) {
601 			*subtest_str = '\0';
602 			if (parse_str_list(subtest_str + 1,
603 					   &env->subtest_selector.whitelist,
604 					   key == ARG_TEST_NAME_GLOB_ALLOWLIST))
605 				return -ENOMEM;
606 		}
607 		if (parse_str_list(arg, &env->test_selector.whitelist,
608 				   key == ARG_TEST_NAME_GLOB_ALLOWLIST))
609 			return -ENOMEM;
610 		break;
611 	}
612 	case ARG_TEST_NAME_GLOB_DENYLIST:
613 	case ARG_TEST_NAME_BLACKLIST: {
614 		char *subtest_str = strchr(arg, '/');
615 
616 		if (subtest_str) {
617 			*subtest_str = '\0';
618 			if (parse_str_list(subtest_str + 1,
619 					   &env->subtest_selector.blacklist,
620 					   key == ARG_TEST_NAME_GLOB_DENYLIST))
621 				return -ENOMEM;
622 		}
623 		if (parse_str_list(arg, &env->test_selector.blacklist,
624 				   key == ARG_TEST_NAME_GLOB_DENYLIST))
625 			return -ENOMEM;
626 		break;
627 	}
628 	case ARG_VERIFIER_STATS:
629 		env->verifier_stats = true;
630 		break;
631 	case ARG_VERBOSE:
632 		env->verbosity = VERBOSE_NORMAL;
633 		if (arg) {
634 			if (strcmp(arg, "v") == 0) {
635 				env->verbosity = VERBOSE_VERY;
636 				extra_prog_load_log_flags = 1;
637 			} else if (strcmp(arg, "vv") == 0) {
638 				env->verbosity = VERBOSE_SUPER;
639 				extra_prog_load_log_flags = 2;
640 			} else {
641 				fprintf(stderr,
642 					"Unrecognized verbosity setting ('%s'), only -v and -vv are supported\n",
643 					arg);
644 				return -EINVAL;
645 			}
646 		}
647 
648 		if (env->verbosity > VERBOSE_NONE) {
649 			if (setenv("SELFTESTS_VERBOSE", "1", 1) == -1) {
650 				fprintf(stderr,
651 					"Unable to setenv SELFTESTS_VERBOSE=1 (errno=%d)",
652 					errno);
653 				return -1;
654 			}
655 		}
656 
657 		break;
658 	case ARG_GET_TEST_CNT:
659 		env->get_test_cnt = true;
660 		break;
661 	case ARG_LIST_TEST_NAMES:
662 		env->list_test_names = true;
663 		break;
664 	case ARGP_KEY_ARG:
665 		argp_usage(state);
666 		break;
667 	case ARGP_KEY_END:
668 		break;
669 	default:
670 		return ARGP_ERR_UNKNOWN;
671 	}
672 	return 0;
673 }
674 
675 static void stdio_hijack(void)
676 {
677 #ifdef __GLIBC__
678 	env.stdout = stdout;
679 	env.stderr = stderr;
680 
681 	if (env.verbosity > VERBOSE_NONE) {
682 		/* nothing to do, output to stdout by default */
683 		return;
684 	}
685 
686 	/* stdout and stderr -> buffer */
687 	fflush(stdout);
688 
689 	stdout = open_memstream(&env.log_buf, &env.log_cnt);
690 	if (!stdout) {
691 		stdout = env.stdout;
692 		perror("open_memstream");
693 		return;
694 	}
695 
696 	stderr = stdout;
697 #endif
698 }
699 
700 static void stdio_restore(void)
701 {
702 #ifdef __GLIBC__
703 	if (stdout == env.stdout)
704 		return;
705 
706 	fclose(stdout);
707 	free(env.log_buf);
708 
709 	env.log_buf = NULL;
710 	env.log_cnt = 0;
711 
712 	stdout = env.stdout;
713 	stderr = env.stderr;
714 #endif
715 }
716 
717 /*
718  * Determine if test_progs is running as a "flavored" test runner and switch
719  * into corresponding sub-directory to load correct BPF objects.
720  *
721  * This is done by looking at executable name. If it contains "-flavor"
722  * suffix, then we are running as a flavored test runner.
723  */
724 int cd_flavor_subdir(const char *exec_name)
725 {
726 	/* General form of argv[0] passed here is:
727 	 * some/path/to/test_progs[-flavor], where -flavor part is optional.
728 	 * First cut out "test_progs[-flavor]" part, then extract "flavor"
729 	 * part, if it's there.
730 	 */
731 	const char *flavor = strrchr(exec_name, '/');
732 
733 	if (!flavor)
734 		return 0;
735 	flavor++;
736 	flavor = strrchr(flavor, '-');
737 	if (!flavor)
738 		return 0;
739 	flavor++;
740 	if (env.verbosity > VERBOSE_NONE)
741 		fprintf(stdout,	"Switching to flavor '%s' subdirectory...\n", flavor);
742 
743 	return chdir(flavor);
744 }
745 
746 #define MAX_BACKTRACE_SZ 128
747 void crash_handler(int signum)
748 {
749 	void *bt[MAX_BACKTRACE_SZ];
750 	size_t sz;
751 
752 	sz = backtrace(bt, ARRAY_SIZE(bt));
753 
754 	if (env.test)
755 		dump_test_log(env.test, true);
756 	if (env.stdout)
757 		stdio_restore();
758 
759 	fprintf(stderr, "Caught signal #%d!\nStack trace:\n", signum);
760 	backtrace_symbols_fd(bt, sz, STDERR_FILENO);
761 }
762 
763 int main(int argc, char **argv)
764 {
765 	static const struct argp argp = {
766 		.options = opts,
767 		.parser = parse_arg,
768 		.doc = argp_program_doc,
769 	};
770 	struct sigaction sigact = {
771 		.sa_handler = crash_handler,
772 		.sa_flags = SA_RESETHAND,
773 	};
774 	int err, i;
775 
776 	sigaction(SIGSEGV, &sigact, NULL);
777 
778 	err = argp_parse(&argp, argc, argv, 0, NULL, &env);
779 	if (err)
780 		return err;
781 
782 	err = cd_flavor_subdir(argv[0]);
783 	if (err)
784 		return err;
785 
786 	/* Use libbpf 1.0 API mode */
787 	libbpf_set_strict_mode(LIBBPF_STRICT_ALL);
788 
789 	libbpf_set_print(libbpf_print_fn);
790 
791 	srand(time(NULL));
792 
793 	env.jit_enabled = is_jit_enabled();
794 	env.nr_cpus = libbpf_num_possible_cpus();
795 	if (env.nr_cpus < 0) {
796 		fprintf(stderr, "Failed to get number of CPUs: %d!\n",
797 			env.nr_cpus);
798 		return -1;
799 	}
800 
801 	save_netns();
802 	stdio_hijack();
803 	env.has_testmod = true;
804 	if (!env.list_test_names && load_bpf_testmod()) {
805 		fprintf(env.stderr, "WARNING! Selftests relying on bpf_testmod.ko will be skipped.\n");
806 		env.has_testmod = false;
807 	}
808 	for (i = 0; i < prog_test_cnt; i++) {
809 		struct prog_test_def *test = &prog_test_defs[i];
810 
811 		env.test = test;
812 		test->test_num = i + 1;
813 
814 		if (!should_run(&env.test_selector,
815 				test->test_num, test->test_name))
816 			continue;
817 
818 		if (env.get_test_cnt) {
819 			env.succ_cnt++;
820 			continue;
821 		}
822 
823 		if (env.list_test_names) {
824 			fprintf(env.stdout, "%s\n", test->test_name);
825 			env.succ_cnt++;
826 			continue;
827 		}
828 
829 		test->run_test();
830 		/* ensure last sub-test is finalized properly */
831 		if (test->subtest_name)
832 			test__end_subtest();
833 
834 		test->tested = true;
835 
836 		dump_test_log(test, test->error_cnt);
837 
838 		fprintf(env.stdout, "#%d %s:%s\n",
839 			test->test_num, test->test_name,
840 			test->error_cnt ? "FAIL" : (test->skip_cnt ? "SKIP" : "OK"));
841 
842 		if (test->error_cnt)
843 			env.fail_cnt++;
844 		else
845 			env.succ_cnt++;
846 		skip_account();
847 
848 		reset_affinity();
849 		restore_netns();
850 		if (test->need_cgroup_cleanup)
851 			cleanup_cgroup_environment();
852 	}
853 	if (!env.list_test_names && env.has_testmod)
854 		unload_bpf_testmod();
855 	stdio_restore();
856 
857 	if (env.get_test_cnt) {
858 		printf("%d\n", env.succ_cnt);
859 		goto out;
860 	}
861 
862 	if (env.list_test_names)
863 		goto out;
864 
865 	fprintf(stdout, "Summary: %d/%d PASSED, %d SKIPPED, %d FAILED\n",
866 		env.succ_cnt, env.sub_succ_cnt, env.skip_cnt, env.fail_cnt);
867 
868 out:
869 	free_str_set(&env.test_selector.blacklist);
870 	free_str_set(&env.test_selector.whitelist);
871 	free(env.test_selector.num_set);
872 	free_str_set(&env.subtest_selector.blacklist);
873 	free_str_set(&env.subtest_selector.whitelist);
874 	free(env.subtest_selector.num_set);
875 	close(env.saved_netns_fd);
876 
877 	if (env.succ_cnt + env.fail_cnt + env.skip_cnt == 0)
878 		return EXIT_NO_TEST;
879 
880 	return env.fail_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
881 }
882