xref: /freebsd/sys/compat/linux/linux_signal.c (revision 1e413cf93298b5b97441a21d9a50fdcd0ee9945e) 
1 /*-
2  * Copyright (c) 1994-1995 S�ren Schmidt
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer
10  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/lock.h>
35 #include <sys/mutex.h>
36 #include <sys/sx.h>
37 #include <sys/proc.h>
38 #include <sys/signalvar.h>
39 #include <sys/syscallsubr.h>
40 #include <sys/sysproto.h>
41 
42 #include "opt_compat.h"
43 
44 #ifdef COMPAT_LINUX32
45 #include <machine/../linux32/linux.h>
46 #include <machine/../linux32/linux32_proto.h>
47 #else
48 #include <machine/../linux/linux.h>
49 #include <machine/../linux/linux_proto.h>
50 #endif
51 #include <compat/linux/linux_signal.h>
52 #include <compat/linux/linux_util.h>
53 #include <compat/linux/linux_emul.h>
54 
55 void
56 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
57 {
58 	int b, l;
59 
60 	SIGEMPTYSET(*bss);
61 	bss->__bits[0] = lss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
62 	bss->__bits[1] = lss->__bits[1];
63 	for (l = 1; l <= LINUX_SIGTBLSZ; l++) {
64 		if (LINUX_SIGISMEMBER(*lss, l)) {
65 			b = linux_to_bsd_signal[_SIG_IDX(l)];
66 			if (b)
67 				SIGADDSET(*bss, b);
68 		}
69 	}
70 }
71 
72 void
73 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
74 {
75 	int b, l;
76 
77 	LINUX_SIGEMPTYSET(*lss);
78 	lss->__bits[0] = bss->__bits[0] & ~((1U << LINUX_SIGTBLSZ) - 1);
79 	lss->__bits[1] = bss->__bits[1];
80 	for (b = 1; b <= LINUX_SIGTBLSZ; b++) {
81 		if (SIGISMEMBER(*bss, b)) {
82 			l = bsd_to_linux_signal[_SIG_IDX(b)];
83 			if (l)
84 				LINUX_SIGADDSET(*lss, l);
85 		}
86 	}
87 }
88 
89 static void
90 linux_to_bsd_sigaction(l_sigaction_t *lsa, struct sigaction *bsa)
91 {
92 
93 	linux_to_bsd_sigset(&lsa->lsa_mask, &bsa->sa_mask);
94 	bsa->sa_handler = PTRIN(lsa->lsa_handler);
95 	bsa->sa_flags = 0;
96 	if (lsa->lsa_flags & LINUX_SA_NOCLDSTOP)
97 		bsa->sa_flags |= SA_NOCLDSTOP;
98 	if (lsa->lsa_flags & LINUX_SA_NOCLDWAIT)
99 		bsa->sa_flags |= SA_NOCLDWAIT;
100 	if (lsa->lsa_flags & LINUX_SA_SIGINFO)
101 		bsa->sa_flags |= SA_SIGINFO;
102 	if (lsa->lsa_flags & LINUX_SA_ONSTACK)
103 		bsa->sa_flags |= SA_ONSTACK;
104 	if (lsa->lsa_flags & LINUX_SA_RESTART)
105 		bsa->sa_flags |= SA_RESTART;
106 	if (lsa->lsa_flags & LINUX_SA_ONESHOT)
107 		bsa->sa_flags |= SA_RESETHAND;
108 	if (lsa->lsa_flags & LINUX_SA_NOMASK)
109 		bsa->sa_flags |= SA_NODEFER;
110 }
111 
112 static void
113 bsd_to_linux_sigaction(struct sigaction *bsa, l_sigaction_t *lsa)
114 {
115 
116 	bsd_to_linux_sigset(&bsa->sa_mask, &lsa->lsa_mask);
117 #ifdef COMPAT_LINUX32
118 	lsa->lsa_handler = (uintptr_t)bsa->sa_handler;
119 #else
120 	lsa->lsa_handler = bsa->sa_handler;
121 #endif
122 	lsa->lsa_restorer = 0;		/* unsupported */
123 	lsa->lsa_flags = 0;
124 	if (bsa->sa_flags & SA_NOCLDSTOP)
125 		lsa->lsa_flags |= LINUX_SA_NOCLDSTOP;
126 	if (bsa->sa_flags & SA_NOCLDWAIT)
127 		lsa->lsa_flags |= LINUX_SA_NOCLDWAIT;
128 	if (bsa->sa_flags & SA_SIGINFO)
129 		lsa->lsa_flags |= LINUX_SA_SIGINFO;
130 	if (bsa->sa_flags & SA_ONSTACK)
131 		lsa->lsa_flags |= LINUX_SA_ONSTACK;
132 	if (bsa->sa_flags & SA_RESTART)
133 		lsa->lsa_flags |= LINUX_SA_RESTART;
134 	if (bsa->sa_flags & SA_RESETHAND)
135 		lsa->lsa_flags |= LINUX_SA_ONESHOT;
136 	if (bsa->sa_flags & SA_NODEFER)
137 		lsa->lsa_flags |= LINUX_SA_NOMASK;
138 }
139 
140 int
141 linux_do_sigaction(struct thread *td, int linux_sig, l_sigaction_t *linux_nsa,
142 		   l_sigaction_t *linux_osa)
143 {
144 	struct sigaction act, oact, *nsa, *osa;
145 	int error, sig;
146 
147 	if (!LINUX_SIG_VALID(linux_sig))
148 		return (EINVAL);
149 
150 	osa = (linux_osa != NULL) ? &oact : NULL;
151 	if (linux_nsa != NULL) {
152 		nsa = &act;
153 		linux_to_bsd_sigaction(linux_nsa, nsa);
154 	} else
155 		nsa = NULL;
156 
157 	if (linux_sig <= LINUX_SIGTBLSZ)
158 		sig = linux_to_bsd_signal[_SIG_IDX(linux_sig)];
159 	else
160 		sig = linux_sig;
161 
162 	error = kern_sigaction(td, sig, nsa, osa, 0);
163 	if (error)
164 		return (error);
165 
166 	if (linux_osa != NULL)
167 		bsd_to_linux_sigaction(osa, linux_osa);
168 
169 	return (0);
170 }
171 
172 
173 int
174 linux_signal(struct thread *td, struct linux_signal_args *args)
175 {
176 	l_sigaction_t nsa, osa;
177 	int error;
178 
179 #ifdef DEBUG
180 	if (ldebug(signal))
181 		printf(ARGS(signal, "%d, %p"),
182 		    args->sig, (void *)(uintptr_t)args->handler);
183 #endif
184 
185 	nsa.lsa_handler = args->handler;
186 	nsa.lsa_flags = LINUX_SA_ONESHOT | LINUX_SA_NOMASK;
187 	LINUX_SIGEMPTYSET(nsa.lsa_mask);
188 
189 	error = linux_do_sigaction(td, args->sig, &nsa, &osa);
190 	td->td_retval[0] = (int)(intptr_t)osa.lsa_handler;
191 
192 	return (error);
193 }
194 
195 int
196 linux_rt_sigaction(struct thread *td, struct linux_rt_sigaction_args *args)
197 {
198 	l_sigaction_t nsa, osa;
199 	int error;
200 
201 #ifdef DEBUG
202 	if (ldebug(rt_sigaction))
203 		printf(ARGS(rt_sigaction, "%ld, %p, %p, %ld"),
204 		    (long)args->sig, (void *)args->act,
205 		    (void *)args->oact, (long)args->sigsetsize);
206 #endif
207 
208 	if (args->sigsetsize != sizeof(l_sigset_t))
209 		return (EINVAL);
210 
211 	if (args->act != NULL) {
212 		error = copyin(args->act, &nsa, sizeof(l_sigaction_t));
213 		if (error)
214 			return (error);
215 	}
216 
217 	error = linux_do_sigaction(td, args->sig,
218 				   args->act ? &nsa : NULL,
219 				   args->oact ? &osa : NULL);
220 
221 	if (args->oact != NULL && !error) {
222 		error = copyout(&osa, args->oact, sizeof(l_sigaction_t));
223 	}
224 
225 	return (error);
226 }
227 
228 static int
229 linux_do_sigprocmask(struct thread *td, int how, l_sigset_t *new,
230 		     l_sigset_t *old)
231 {
232 	sigset_t omask, nmask;
233 	sigset_t *nmaskp;
234 	int error;
235 
236 	td->td_retval[0] = 0;
237 
238 	switch (how) {
239 	case LINUX_SIG_BLOCK:
240 		how = SIG_BLOCK;
241 		break;
242 	case LINUX_SIG_UNBLOCK:
243 		how = SIG_UNBLOCK;
244 		break;
245 	case LINUX_SIG_SETMASK:
246 		how = SIG_SETMASK;
247 		break;
248 	default:
249 		return (EINVAL);
250 	}
251 	if (new != NULL) {
252 		linux_to_bsd_sigset(new, &nmask);
253 		nmaskp = &nmask;
254 	} else
255 		nmaskp = NULL;
256 	error = kern_sigprocmask(td, how, nmaskp, &omask, 0);
257 	if (error == 0 && old != NULL)
258 		bsd_to_linux_sigset(&omask, old);
259 
260 	return (error);
261 }
262 
263 int
264 linux_sigprocmask(struct thread *td, struct linux_sigprocmask_args *args)
265 {
266 	l_osigset_t mask;
267 	l_sigset_t set, oset;
268 	int error;
269 
270 #ifdef DEBUG
271 	if (ldebug(sigprocmask))
272 		printf(ARGS(sigprocmask, "%d, *, *"), args->how);
273 #endif
274 
275 	if (args->mask != NULL) {
276 		error = copyin(args->mask, &mask, sizeof(l_osigset_t));
277 		if (error)
278 			return (error);
279 		LINUX_SIGEMPTYSET(set);
280 		set.__bits[0] = mask;
281 	}
282 
283 	error = linux_do_sigprocmask(td, args->how,
284 				     args->mask ? &set : NULL,
285 				     args->omask ? &oset : NULL);
286 
287 	if (args->omask != NULL && !error) {
288 		mask = oset.__bits[0];
289 		error = copyout(&mask, args->omask, sizeof(l_osigset_t));
290 	}
291 
292 	return (error);
293 }
294 
295 int
296 linux_rt_sigprocmask(struct thread *td, struct linux_rt_sigprocmask_args *args)
297 {
298 	l_sigset_t set, oset;
299 	int error;
300 
301 #ifdef DEBUG
302 	if (ldebug(rt_sigprocmask))
303 		printf(ARGS(rt_sigprocmask, "%d, %p, %p, %ld"),
304 		    args->how, (void *)args->mask,
305 		    (void *)args->omask, (long)args->sigsetsize);
306 #endif
307 
308 	if (args->sigsetsize != sizeof(l_sigset_t))
309 		return EINVAL;
310 
311 	if (args->mask != NULL) {
312 		error = copyin(args->mask, &set, sizeof(l_sigset_t));
313 		if (error)
314 			return (error);
315 	}
316 
317 	error = linux_do_sigprocmask(td, args->how,
318 				     args->mask ? &set : NULL,
319 				     args->omask ? &oset : NULL);
320 
321 	if (args->omask != NULL && !error) {
322 		error = copyout(&oset, args->omask, sizeof(l_sigset_t));
323 	}
324 
325 	return (error);
326 }
327 
328 int
329 linux_sgetmask(struct thread *td, struct linux_sgetmask_args *args)
330 {
331 	struct proc *p = td->td_proc;
332 	l_sigset_t mask;
333 
334 #ifdef DEBUG
335 	if (ldebug(sgetmask))
336 		printf(ARGS(sgetmask, ""));
337 #endif
338 
339 	PROC_LOCK(p);
340 	bsd_to_linux_sigset(&td->td_sigmask, &mask);
341 	PROC_UNLOCK(p);
342 	td->td_retval[0] = mask.__bits[0];
343 	return (0);
344 }
345 
346 int
347 linux_ssetmask(struct thread *td, struct linux_ssetmask_args *args)
348 {
349 	struct proc *p = td->td_proc;
350 	l_sigset_t lset;
351 	sigset_t bset;
352 
353 #ifdef DEBUG
354 	if (ldebug(ssetmask))
355 		printf(ARGS(ssetmask, "%08lx"), (unsigned long)args->mask);
356 #endif
357 
358 	PROC_LOCK(p);
359 	bsd_to_linux_sigset(&td->td_sigmask, &lset);
360 	td->td_retval[0] = lset.__bits[0];
361 	LINUX_SIGEMPTYSET(lset);
362 	lset.__bits[0] = args->mask;
363 	linux_to_bsd_sigset(&lset, &bset);
364 	td->td_sigmask = bset;
365 	SIG_CANTMASK(td->td_sigmask);
366 	signotify(td);
367 	PROC_UNLOCK(p);
368 	return (0);
369 }
370 
371 /*
372  * MPSAFE
373  */
374 int
375 linux_sigpending(struct thread *td, struct linux_sigpending_args *args)
376 {
377 	struct proc *p = td->td_proc;
378 	sigset_t bset;
379 	l_sigset_t lset;
380 	l_osigset_t mask;
381 
382 #ifdef DEBUG
383 	if (ldebug(sigpending))
384 		printf(ARGS(sigpending, "*"));
385 #endif
386 
387 	PROC_LOCK(p);
388 	bset = p->p_siglist;
389 	SIGSETOR(bset, td->td_siglist);
390 	SIGSETAND(bset, td->td_sigmask);
391 	PROC_UNLOCK(p);
392 	bsd_to_linux_sigset(&bset, &lset);
393 	mask = lset.__bits[0];
394 	return (copyout(&mask, args->mask, sizeof(mask)));
395 }
396 
397 /*
398  * MPSAFE
399  */
400 int
401 linux_rt_sigpending(struct thread *td, struct linux_rt_sigpending_args *args)
402 {
403 	struct proc *p = td->td_proc;
404 	sigset_t bset;
405 	l_sigset_t lset;
406 
407 	if (args->sigsetsize > sizeof(lset))
408 		return EINVAL;
409 		/* NOT REACHED */
410 
411 #ifdef DEBUG
412 	if (ldebug(rt_sigpending))
413 		printf(ARGS(rt_sigpending, "*"));
414 #endif
415 
416 	PROC_LOCK(p);
417 	bset = p->p_siglist;
418 	SIGSETOR(bset, td->td_siglist);
419 	SIGSETAND(bset, td->td_sigmask);
420 	PROC_UNLOCK(p);
421 	bsd_to_linux_sigset(&bset, &lset);
422 	return (copyout(&lset, args->set, args->sigsetsize));
423 }
424 
425 /*
426  * MPSAFE
427  */
428 int
429 linux_rt_sigtimedwait(struct thread *td,
430 	struct linux_rt_sigtimedwait_args *args)
431 {
432 	int error;
433 	l_timeval ltv;
434 	struct timeval tv;
435 	struct timespec ts, *tsa;
436 	l_sigset_t lset;
437 	sigset_t bset;
438 	l_siginfo_t linfo;
439 	ksiginfo_t info;
440 
441 #ifdef DEBUG
442 	if (ldebug(rt_sigtimedwait))
443 		printf(ARGS(rt_sigtimedwait, "*"));
444 #endif
445 	if (args->sigsetsize != sizeof(l_sigset_t))
446 		return (EINVAL);
447 
448 	if ((error = copyin(args->mask, &lset, sizeof(lset))))
449 		return (error);
450 	linux_to_bsd_sigset(&lset, &bset);
451 
452 	tsa = NULL;
453 	if (args->timeout) {
454 		if ((error = copyin(args->timeout, &ltv, sizeof(ltv))))
455 			return (error);
456 #ifdef DEBUG
457 		if (ldebug(rt_sigtimedwait))
458 			printf(LMSG("linux_rt_sigtimedwait: incoming timeout (%d/%d)\n"),
459 				ltv.tv_sec, ltv.tv_usec);
460 #endif
461 		tv.tv_sec = (long)ltv.tv_sec;
462 		tv.tv_usec = (suseconds_t)ltv.tv_usec;
463 		if (itimerfix(&tv)) {
464 			/*
465 			 * The timeout was invalid. Convert it to something
466 			 * valid that will act as it does under Linux.
467 			 */
468 			tv.tv_sec += tv.tv_usec / 1000000;
469 			tv.tv_usec %= 1000000;
470 			if (tv.tv_usec < 0) {
471 				tv.tv_sec -= 1;
472 				tv.tv_usec += 1000000;
473 			}
474 			if (tv.tv_sec < 0)
475 				timevalclear(&tv);
476 #ifdef DEBUG
477 			if (ldebug(rt_sigtimedwait))
478 				printf(LMSG("linux_rt_sigtimedwait: converted timeout (%jd/%ld)\n"),
479 					(intmax_t)tv.tv_sec, tv.tv_usec);
480 #endif
481 		}
482 		TIMEVAL_TO_TIMESPEC(&tv, &ts);
483 		tsa = &ts;
484 	}
485 	error = kern_sigtimedwait(td, bset, &info, tsa);
486 #ifdef DEBUG
487 	if (ldebug(rt_sigtimedwait))
488 		printf(LMSG("linux_rt_sigtimedwait: sigtimedwait returning (%d)\n"), error);
489 #endif
490 	if (error)
491 		return (error);
492 
493 	if (args->ptr) {
494 		memset(&linfo, 0, sizeof(linfo));
495 		linfo.lsi_signo = info.ksi_signo;
496 		error = copyout(&linfo, args->ptr, sizeof(linfo));
497 	}
498 
499 	/* Repost if we got an error. */
500 	if (error && info.ksi_signo) {
501 		PROC_LOCK(td->td_proc);
502 		tdsignal(td->td_proc, td, info.ksi_signo, &info);
503 		PROC_UNLOCK(td->td_proc);
504 	} else
505 		td->td_retval[0] = info.ksi_signo;
506 
507 	return (error);
508 }
509 
510 int
511 linux_kill(struct thread *td, struct linux_kill_args *args)
512 {
513 	struct kill_args /* {
514 	    int pid;
515 	    int signum;
516 	} */ tmp;
517 
518 #ifdef DEBUG
519 	if (ldebug(kill))
520 		printf(ARGS(kill, "%d, %d"), args->pid, args->signum);
521 #endif
522 
523 	/*
524 	 * Allow signal 0 as a means to check for privileges
525 	 */
526 	if (!LINUX_SIG_VALID(args->signum) && args->signum != 0)
527 		return EINVAL;
528 
529 	if (args->signum > 0 && args->signum <= LINUX_SIGTBLSZ)
530 		tmp.signum = linux_to_bsd_signal[_SIG_IDX(args->signum)];
531 	else
532 		tmp.signum = args->signum;
533 
534 	tmp.pid = args->pid;
535 	return (kill(td, &tmp));
536 }
537 
538 int
539 linux_tgkill(struct thread *td, struct linux_tgkill_args *args)
540 {
541    	struct linux_emuldata *em;
542 	struct linux_kill_args ka;
543 	struct proc *p;
544 
545 #ifdef DEBUG
546 	if (ldebug(tgkill))
547 		printf(ARGS(tgkill, "%d, %d, %d"), args->tgid, args->pid, args->sig);
548 #endif
549 
550 	ka.pid = args->pid;
551 	ka.signum = args->sig;
552 
553 	if (args->tgid == -1)
554 	   	return linux_kill(td, &ka);
555 
556 	if ((p = pfind(args->pid)) == NULL)
557 	      	return ESRCH;
558 
559 	if (p->p_sysent != &elf_linux_sysvec)
560 		return ESRCH;
561 
562 	PROC_UNLOCK(p);
563 
564 	em = em_find(p, EMUL_DONTLOCK);
565 
566 	if (em == NULL) {
567 #ifdef DEBUG
568 		printf("emuldata not found in tgkill.\n");
569 #endif
570 		return ESRCH;
571 	}
572 
573 	if (em->shared->group_pid != args->tgid)
574 	   	return ESRCH;
575 
576 	return linux_kill(td, &ka);
577 }
578 
579 int
580 linux_tkill(struct thread *td, struct linux_tkill_args *args)
581 {
582 #ifdef DEBUG
583 	if (ldebug(tkill))
584 		printf(ARGS(tkill, "%i, %i"), args->tid, args->sig);
585 #endif
586 
587 	return (linux_kill(td, (struct linux_kill_args *) args));
588 }
589