xref: /freebsd/tests/sys/kern/sigwait.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * Copyright (c) 2022 Dmitry Chagin <dchagin@FreeBSD.org>
3  *
4  * SPDX-License-Identifier: BSD-2-Clause
5  */
6 #include <sys/cdefs.h>
7 #include <sys/limits.h>
8 #include <sys/time.h>
9 #include <sys/sysctl.h>
10 #include <sys/user.h>
11 #include <sys/wait.h>
12 
13 #include <err.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <string.h>
17 #include <errno.h>
18 #include <signal.h>
19 #include <stdbool.h>
20 #include <unistd.h>
21 
22 #include <atf-c.h>
23 
24 
25 static inline struct timespec
26 make_timespec(time_t s, long int ns)
27 {
28 	struct timespec rts;
29 
30 	rts.tv_sec = s;
31 	rts.tv_nsec = ns;
32 	return (rts);
33 }
34 
35 static void
36 dummy_sig_handler(int sig)
37 {
38 
39 }
40 
41 static void
42 dummy_sigchld(int signo, siginfo_t *info, void *ctx)
43 {
44 
45 }
46 
47 static void
48 support_signal(int sig, sig_t handler)
49 {
50 
51 	ATF_REQUIRE(signal(sig, handler) != SIG_ERR);
52 }
53 
54 static void
55 support_sysctlset(const char *name, int32_t val)
56 {
57 
58 	ATF_REQUIRE(sysctlbyname(name, NULL, NULL, &val, sizeof(val)) == 0);
59 }
60 
61 static timer_t
62 support_create_timer(uint64_t sec, long int nsec, bool repeat,
63     bool callback)
64 {
65 	struct sigevent ev = {
66 		.sigev_notify = SIGEV_SIGNAL,
67 		.sigev_signo = SIGALRM
68 	};
69 	struct itimerspec its =
70 	{
71 		{ .tv_sec = repeat ? sec : 0, .tv_nsec = repeat ? nsec : 0 },
72 		{ .tv_sec = sec, .tv_nsec = nsec }
73 	};
74 	struct sigaction sa;
75 	timer_t timerid;
76 
77 	if (callback) {
78 		sa.sa_handler = dummy_sig_handler;
79 		sigemptyset (&sa.sa_mask);
80 		sa.sa_flags = 0;
81 		ATF_REQUIRE(sigaction(SIGALRM, &sa, NULL) == 0);
82 	}
83 	ATF_REQUIRE(timer_create(CLOCK_REALTIME, &ev, &timerid) == 0);
84 	ATF_REQUIRE(timer_settime(timerid, 0, &its, NULL) == 0);
85 	return (timerid);
86 }
87 
88 static void
89 support_delete_timer(timer_t timer)
90 {
91 
92 	ATF_REQUIRE(timer_delete(timer) == 0);
93 	support_signal(SIGALRM, SIG_DFL);
94 }
95 
96 static pid_t
97 support_create_sig_proc(int sig, int count, unsigned int usec)
98 {
99 	pid_t pid, cpid;
100 
101 	pid = getpid();
102 	ATF_REQUIRE(pid > 0);
103 	cpid = fork();
104 	ATF_REQUIRE(cpid >= 0);
105 
106 	if (cpid == 0) {
107 		while (count-- > 0) {
108 			usleep(usec);
109 			if (kill(pid, sig) == -1)
110 				break;
111 		}
112 		exit(0);
113 	}
114 	return (cpid);
115 }
116 
117 #define TIMESPEC_HZ     1000000000
118 
119 static void
120 test_sigtimedwait_timeout_eagain(time_t sec, bool zero_tmo)
121 {
122 	struct timespec ts, timeout, now;
123 	sigset_t ss;
124 	int rv;
125 
126 	ATF_REQUIRE(clock_gettime(CLOCK_REALTIME, &ts) == 0);
127 
128 	timeout = make_timespec(sec, zero_tmo ? 0 : TIMESPEC_HZ/2);
129 	timespecadd(&ts, &timeout, &ts);
130 
131 	sigemptyset(&ss);
132 	sigaddset(&ss, SIGUSR1);
133 	rv = sigtimedwait(&ss, NULL, &timeout);
134 	ATF_REQUIRE_EQ_MSG(-1, rv,
135 	    "sigtimedwait () should fail: rv %d, errno %d", rv, errno);
136 	ATF_REQUIRE_EQ_MSG(EAGAIN, errno,
137 	    "sigtimedwait() should fail with EAGAIN: rv %d, errno %d",
138 	    rv, errno);
139 	/* now >= ts */
140 	ATF_REQUIRE(clock_gettime(CLOCK_REALTIME, &now) == 0);
141 	ATF_REQUIRE_MSG(timespeccmp(&now, &ts, >=) == true,
142 	    "timespeccmp: now { %jd.%ld } < ts { %jd.%ld }",
143 	    (intmax_t)now.tv_sec, now.tv_nsec,
144 	    (intmax_t)ts.tv_sec, ts.tv_nsec);
145 }
146 
147 ATF_TC(test_sigtimedwait_timeout_eagain0);
148 ATF_TC_HEAD(test_sigtimedwait_timeout_eagain0, tc)
149 {
150 
151 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits immediately");
152 }
153 
154 ATF_TC_BODY(test_sigtimedwait_timeout_eagain0, tc)
155 {
156 
157 	test_sigtimedwait_timeout_eagain(0, true);
158 }
159 
160 ATF_TC(test_sigtimedwait_timeout_eagain1);
161 ATF_TC_HEAD(test_sigtimedwait_timeout_eagain1, tc)
162 {
163 
164 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits immediately");
165 }
166 
167 ATF_TC_BODY(test_sigtimedwait_timeout_eagain1, tc)
168 {
169 
170 	test_sigtimedwait_timeout_eagain(-1, true);
171 }
172 
173 ATF_TC(test_sigtimedwait_timeout_eagain2);
174 ATF_TC_HEAD(test_sigtimedwait_timeout_eagain2, tc)
175 {
176 
177 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits immediately");
178 }
179 
180 ATF_TC_BODY(test_sigtimedwait_timeout_eagain2, tc)
181 {
182 
183 	test_sigtimedwait_timeout_eagain(-1, false);
184 }
185 
186 ATF_TC(test_sigtimedwait_timeout_eagain3);
187 ATF_TC_HEAD(test_sigtimedwait_timeout_eagain3, tc)
188 {
189 
190 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits after specified timeout");
191 }
192 
193 ATF_TC_BODY(test_sigtimedwait_timeout_eagain3, tc)
194 {
195 
196 	test_sigtimedwait_timeout_eagain(0, false);
197 }
198 
199 ATF_TC(test_sigtimedwait_large_timeout_eintr);
200 ATF_TC_HEAD(test_sigtimedwait_large_timeout_eintr, tc)
201 {
202 
203 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits with EINTR");
204 }
205 
206 ATF_TC_BODY(test_sigtimedwait_large_timeout_eintr, tc)
207 {
208 	struct timespec ts;
209 	timer_t timerid;
210 	sigset_t ss;
211 	int rv;
212 
213 	ts = make_timespec(LONG_MAX, 0);
214 	timerid = support_create_timer(0, 100000000, false, true);
215 
216 	sigemptyset(&ss);
217 	sigaddset(&ss, SIGUSR1);
218 	rv = sigtimedwait(&ss, NULL, &ts);
219 	ATF_REQUIRE_EQ_MSG(-1, rv,
220 	    "sigtimedwait () should fail: rv %d, errno %d", rv, errno);
221 	ATF_REQUIRE_EQ_MSG(EINTR, errno,
222 	    "sigtimedwait() should fail with EINTR: rv %d, errno %d",
223 	    rv, errno);
224 	support_delete_timer(timerid);
225 }
226 
227 ATF_TC(test_sigtimedwait_infinity);
228 ATF_TC_HEAD(test_sigtimedwait_infinity, tc)
229 {
230 
231 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits with EINTR");
232 }
233 
234 ATF_TC_BODY(test_sigtimedwait_infinity, tc)
235 {
236 	timer_t timerid;
237 	sigset_t ss;
238 	int rv;
239 
240 	timerid = support_create_timer(0, 100000000, false, true);
241 
242 	sigemptyset(&ss);
243 	sigaddset(&ss, SIGUSR1);
244 	rv = sigtimedwait(&ss, NULL, NULL);
245 	ATF_REQUIRE_EQ_MSG(-1, rv,
246 	    "sigtimedwait () should fail: rv %d, errno %d", rv, errno);
247 	ATF_REQUIRE_EQ_MSG(EINTR, errno,
248 	    "sigtimedwait() should fail with EINTR: rv %d, errno %d",
249 	    rv, errno);
250 	support_delete_timer(timerid);
251 }
252 
253 ATF_TC(test_sigtimedwait_einval);
254 ATF_TC_HEAD(test_sigtimedwait_einval, tc)
255 {
256 
257 	atf_tc_set_md_var(tc, "descr", "Check if sigtimedwait exits with EINVAL");
258 }
259 
260 ATF_TC_BODY(test_sigtimedwait_einval, tc)
261 {
262 	struct timespec ts;
263 	timer_t timerid;
264 	sigset_t ss;
265 	int rv;
266 
267 	ts = make_timespec(0, -1);
268 	timerid = support_create_timer(0, 100000000, false, true);
269 
270 	sigemptyset(&ss);
271 	sigaddset(&ss, SIGUSR1);
272 	rv = sigtimedwait(&ss, NULL, &ts);
273 	ATF_REQUIRE_EQ_MSG(-1, rv,
274 	    "sigtimedwait () should fail: rv %d, errno %d", rv, errno);
275 	ATF_REQUIRE_EQ_MSG(EINVAL, errno,
276 	    "sigtimedwait() should fail with EINVAL: rv %d, errno %d",
277 	    rv, errno);
278 	support_delete_timer(timerid);
279 }
280 
281 ATF_TC(test_sigwait_eintr);
282 ATF_TC_HEAD(test_sigwait_eintr, tc)
283 {
284 
285 	atf_tc_set_md_var(tc, "descr", "Check if sigwait exits with EINTR");
286 }
287 
288 ATF_TC_BODY(test_sigwait_eintr, tc)
289 {
290 	timer_t timerid;
291 	sigset_t ss;
292 	int rv, sig, pid;
293 
294 	support_signal(SIGUSR1, dummy_sig_handler);
295 
296 	pid = support_create_sig_proc(SIGUSR1, 1, 400000);
297 	timerid = support_create_timer(0, 200000, false, true);
298 
299 	sigemptyset(&ss);
300 	sigaddset(&ss, SIGUSR1);
301 	rv = sigwait(&ss, &sig);
302 	ATF_REQUIRE_EQ_MSG(0, rv,
303 	    "sigwait() should not fail: rv %d, errno %d", rv, errno);
304 	ATF_REQUIRE_EQ_MSG(SIGUSR1, sig,
305 	    "sigwait() should return SIGUSR1: rv %d, sig %d", rv, sig);
306 	ATF_REQUIRE(waitid(P_PID, pid, NULL, WEXITED) == 0);
307 	support_delete_timer(timerid);
308 }
309 
310 ATF_TC(test_sigwaitinfo_eintr);
311 ATF_TC_HEAD(test_sigwaitinfo_eintr, tc)
312 {
313 
314 	atf_tc_set_md_var(tc, "descr", "Check if sigwaitinfo exits with EINTR");
315 }
316 
317 ATF_TC_BODY(test_sigwaitinfo_eintr, tc)
318 {
319 	timer_t timerid;
320 	sigset_t ss;
321 	int rv;
322 
323 	timerid = support_create_timer(0, 100000000, false, true);
324 
325 	sigemptyset(&ss);
326 	sigaddset(&ss, SIGUSR1);
327 	rv = sigwaitinfo(&ss, NULL);
328 	ATF_REQUIRE_EQ_MSG(-1, rv,
329 	    "sigwaitinfo() should fail, rv %d != -1", rv);
330 	ATF_REQUIRE_EQ_MSG(EINTR, errno,
331 	    "sigwaitinfo() should fail errno %d != EINTR", errno);
332 	support_delete_timer(timerid);
333 }
334 
335 /*
336  * Test kern.sig_discard_ign knob (default true).
337  * See commit bc387624
338  */
339 static void
340 test_sig_discard_ign(bool ignore)
341 {
342 	struct timespec ts;
343 	sigset_t mask;
344 	pid_t pid;
345 	int rv;
346 
347 	support_signal(SIGUSR2, SIG_IGN);
348 
349 	if (ignore)
350 		support_sysctlset("kern.sig_discard_ign", 1);
351 	else
352 		support_sysctlset("kern.sig_discard_ign", 0);
353 
354 	sigemptyset(&mask);
355 	sigaddset(&mask, SIGUSR2);
356 	ATF_REQUIRE(sigprocmask(SIG_SETMASK, &mask, NULL) == 0);
357 
358 	pid = support_create_sig_proc(SIGUSR2, 1, 100000);
359 
360 	ts = make_timespec(1, 0);
361 	rv = sigtimedwait(&mask, NULL, &ts);
362 	if (ignore == true) {
363 		ATF_REQUIRE_EQ_MSG(-1, rv,
364 		    "sigtimedwait() ign=on should fail, rv %d != -1", rv);
365 		ATF_REQUIRE_EQ_MSG(EAGAIN, errno,
366 		    "sigtimedwait() ign=on should fail with EAGAIN errno %d",
367 		    errno);
368 	} else
369 		ATF_REQUIRE_EQ_MSG(SIGUSR2, rv,
370 		    "sigtimedwait() ign=off should return SIGUSR2, rv %d errno %d",
371 		    rv, errno);
372 	ATF_REQUIRE(waitid(P_PID, pid, NULL, WEXITED) == 0);
373 }
374 
375 static void
376 support_check_siginfo(int code, int status, pid_t pid,
377     siginfo_t *si, int sig)
378 {
379 
380 	ATF_REQUIRE_EQ_MSG(sig, si->si_signo,
381 	    "check_siginfo: si_signo %d != sig %d", si->si_signo, sig);
382 	ATF_REQUIRE_EQ_MSG(code, si->si_code,
383 	    "check_siginfo: si_code %d != code %d", si->si_code, code);
384 	ATF_REQUIRE_EQ_MSG(status, si->si_status,
385 	    "check_siginfo: si_status %d != status %d", si->si_status, status);
386 	ATF_REQUIRE_EQ_MSG(pid, si->si_pid,
387 	    "check_siginfo: si_pid %d != pid %d", si->si_pid, pid);
388 }
389 
390 static void
391 support_check_sigchld(sigset_t *set, int code, int status, pid_t pid,
392     bool dequeue)
393 {
394 	siginfo_t si;
395 	int sig, kpid;
396 
397 	if (dequeue == true)
398 		kpid = support_create_sig_proc(SIGUSR2, 1, 1000000);
399 
400 	sig = sigwaitinfo(set, &si);
401 	if (dequeue == true) {
402 		ATF_REQUIRE_EQ_MSG(-1, sig,
403 		    "sigwaitinfo() should fail, sig %d != -1", sig);
404 		ATF_REQUIRE_EQ_MSG(EINTR, errno,
405 		    "sigwaitinfo() should fail errno %d != EINTR", errno);
406 	} else
407 		ATF_REQUIRE_EQ_MSG(SIGCHLD, sig,
408 		    "sigwaitinfo() %d != SIGCHLD", sig);
409 	if (dequeue == false)
410 		support_check_siginfo(code, status, pid, &si, SIGCHLD);
411 	if (dequeue == true)
412 		ATF_REQUIRE(waitid(P_PID, kpid, &si, WEXITED) == 0);
413 }
414 
415 static void
416 test_child(void)
417 {
418 
419 	raise(SIGSTOP);
420 	while (1)
421 		pause();
422 }
423 
424 /*
425  * Test kern.wait_dequeue_sigchld knob.
426  */
427 static void
428 test_wait_dequeue_sigchld(bool dequeue)
429 {
430 	struct sigaction sa;
431 	siginfo_t si;
432 	sigset_t set;
433 	pid_t pid;
434 
435 	sa.sa_flags = SA_SIGINFO | SA_RESTART;
436 	sa.sa_sigaction = dummy_sigchld;
437 	sigemptyset(&sa.sa_mask);
438 	ATF_REQUIRE(sigaction(SIGCHLD, &sa, NULL) == 0);
439 
440 	support_signal(SIGUSR2, dummy_sig_handler);
441 
442 	sigemptyset(&set);
443 	sigaddset(&set, SIGCHLD);
444 	ATF_REQUIRE(sigprocmask(SIG_BLOCK, &set, NULL) == 0);
445 
446 	if (dequeue)
447 		support_sysctlset("kern.wait_dequeue_sigchld", 1);
448 	else
449 		support_sysctlset("kern.wait_dequeue_sigchld", 0);
450 
451 	pid = fork();
452 	ATF_REQUIRE(pid >= 0);
453 	if (pid == 0) {
454 		test_child();
455 		exit(0);
456 	}
457 
458 	bzero(&si, sizeof(si));
459 	ATF_REQUIRE(waitid(P_PID, pid, &si, WSTOPPED) == 0);
460 
461 	support_check_siginfo(CLD_STOPPED, SIGSTOP, pid, &si, SIGCHLD);
462 	support_check_sigchld(&set, CLD_STOPPED, SIGSTOP, pid, dequeue);
463 
464 	ATF_REQUIRE(kill(pid, SIGCONT) == 0);
465 
466 	bzero(&si, sizeof(si));
467 	ATF_REQUIRE(waitid(P_PID, pid, &si, WCONTINUED) == 0);
468 
469 	support_check_siginfo(CLD_CONTINUED, SIGCONT, pid, &si, SIGCHLD);
470 	support_check_sigchld(&set, CLD_CONTINUED, SIGCONT, pid, dequeue);
471 
472 	ATF_REQUIRE(kill(pid, SIGKILL) == 0);
473 
474 	bzero(&si, sizeof(si));
475 	ATF_REQUIRE(waitid(P_PID, pid, &si, WEXITED) == 0);
476 
477 	support_check_siginfo(CLD_KILLED, SIGKILL, pid, &si, SIGCHLD);
478 }
479 
480 ATF_TC_WITH_CLEANUP(test_sig_discard_ign_true);
481 ATF_TC_HEAD(test_sig_discard_ign_true, tc)
482 {
483 
484 	atf_tc_set_md_var(tc, "require.user", "root");
485 	atf_tc_set_md_var(tc, "descr", "Test kern.sig_discard_ign on");
486 }
487 
488 ATF_TC_BODY(test_sig_discard_ign_true, tc)
489 {
490 
491 	test_sig_discard_ign(true);
492 }
493 
494 ATF_TC_CLEANUP(test_sig_discard_ign_true, tc)
495 {
496 
497 	support_sysctlset("kern.sig_discard_ign", 1);
498 }
499 
500 ATF_TC_WITH_CLEANUP(test_sig_discard_ign_false);
501 ATF_TC_HEAD(test_sig_discard_ign_false, tc)
502 {
503 
504 	atf_tc_set_md_var(tc, "require.user", "root");
505 	atf_tc_set_md_var(tc, "descr", "Test kern.sig_discard_ign off");
506 }
507 
508 ATF_TC_BODY(test_sig_discard_ign_false, tc)
509 {
510 
511 	test_sig_discard_ign(false);
512 }
513 
514 ATF_TC_CLEANUP(test_sig_discard_ign_false, tc)
515 {
516 
517 	support_sysctlset("kern.sig_discard_ign", 1);
518 }
519 
520 ATF_TC_WITH_CLEANUP(test_wait_dequeue_sigchld_true);
521 ATF_TC_HEAD(test_wait_dequeue_sigchld_true, tc)
522 {
523 
524 	atf_tc_set_md_var(tc, "require.user", "root");
525 	atf_tc_set_md_var(tc, "descr", "Test kern.wait_dequeue_sigchld on");
526 }
527 
528 ATF_TC_BODY(test_wait_dequeue_sigchld_true, tc)
529 {
530 
531 	test_wait_dequeue_sigchld(true);
532 }
533 
534 ATF_TC_CLEANUP(test_wait_dequeue_sigchld_true, tc)
535 {
536 
537 	support_sysctlset("kern.wait_dequeue_sigchld", 1);
538 }
539 
540 ATF_TC_WITH_CLEANUP(test_wait_dequeue_sigchld_false);
541 ATF_TC_HEAD(test_wait_dequeue_sigchld_false, tc)
542 {
543 
544 	atf_tc_set_md_var(tc, "require.user", "root");
545 	atf_tc_set_md_var(tc, "descr", "Test kern.wait_dequeue_sigchld off");
546 }
547 
548 ATF_TC_BODY(test_wait_dequeue_sigchld_false, tc)
549 {
550 
551 	test_wait_dequeue_sigchld(false);
552 }
553 
554 ATF_TC_CLEANUP(test_wait_dequeue_sigchld_false, tc)
555 {
556 
557 	support_sysctlset("kern.wait_dequeue_sigchld", 1);
558 }
559 
560 ATF_TP_ADD_TCS(tp)
561 {
562 
563 	ATF_TP_ADD_TC(tp, test_sigtimedwait_timeout_eagain0);
564 	ATF_TP_ADD_TC(tp, test_sigtimedwait_timeout_eagain1);
565 	ATF_TP_ADD_TC(tp, test_sigtimedwait_timeout_eagain2);
566 	ATF_TP_ADD_TC(tp, test_sigtimedwait_timeout_eagain3);
567 
568 	ATF_TP_ADD_TC(tp, test_sigtimedwait_large_timeout_eintr);
569 	ATF_TP_ADD_TC(tp, test_sigtimedwait_infinity);
570 
571 	ATF_TP_ADD_TC(tp, test_sigtimedwait_einval);
572 
573 	ATF_TP_ADD_TC(tp, test_sigwait_eintr);
574 	ATF_TP_ADD_TC(tp, test_sigwaitinfo_eintr);
575 
576 	ATF_TP_ADD_TC(tp, test_sig_discard_ign_true);
577 	ATF_TP_ADD_TC(tp, test_sig_discard_ign_false);
578 
579 	ATF_TP_ADD_TC(tp, test_wait_dequeue_sigchld_true);
580 	ATF_TP_ADD_TC(tp, test_wait_dequeue_sigchld_false);
581 
582 	return (atf_no_error());
583 }
584