xref: /netbsd-src/sys/compat/linux/common/linux_signal.c (revision b2a8932dbe9fdfd3d41d60d0a04b9a3ba294763d) 
1 /*	$NetBSD: linux_signal.c,v 1.80 2018/01/07 21:14:38 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1995, 1998 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Frank van der Linden and Eric Haszlakiewicz.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*
32  * heavily from: svr4_signal.c,v 1.7 1995/01/09 01:04:21 christos Exp
33  */
34 
35 /*
36  *   Functions in multiarch:
37  *	linux_sys_signal	: linux_sig_notalpha.c
38  *	linux_sys_siggetmask	: linux_sig_notalpha.c
39  *	linux_sys_sigsetmask	: linux_sig_notalpha.c
40  *	linux_sys_pause		: linux_sig_notalpha.c
41  *	linux_sys_sigaction	: linux_sigaction.c
42  *
43  */
44 
45 /*
46  *   Unimplemented:
47  *	linux_sys_rt_sigtimedwait	: sigsuspend w/timeout.
48  */
49 
50 #include <sys/cdefs.h>
51 __KERNEL_RCSID(0, "$NetBSD: linux_signal.c,v 1.80 2018/01/07 21:14:38 christos Exp $");
52 
53 #define COMPAT_LINUX 1
54 
55 #include <sys/param.h>
56 #include <sys/systm.h>
57 #include <sys/namei.h>
58 #include <sys/proc.h>
59 #include <sys/filedesc.h>
60 #include <sys/ioctl.h>
61 #include <sys/mount.h>
62 #include <sys/kernel.h>
63 #include <sys/signal.h>
64 #include <sys/signalvar.h>
65 #include <sys/wait.h>
66 
67 #include <sys/syscallargs.h>
68 
69 #include <compat/linux/common/linux_types.h>
70 #include <compat/linux/common/linux_signal.h>
71 #include <compat/linux/common/linux_emuldata.h>
72 #include <compat/linux/common/linux_siginfo.h>
73 #include <compat/linux/common/linux_sigevent.h>
74 #include <compat/linux/common/linux_util.h>
75 #include <compat/linux/common/linux_ipc.h>
76 #include <compat/linux/common/linux_sem.h>
77 #include <compat/linux/common/linux_errno.h>
78 #include <compat/linux/common/linux_sched.h>
79 
80 #include <compat/linux/linux_syscallargs.h>
81 
82 /* Locally used defines (in bsd<->linux conversion functions): */
83 #define	linux_sigemptyset(s)	memset((s), 0, sizeof(*(s)))
84 #define	linux_sigismember(s, n)	((s)->sig[((n) - 1) / LINUX__NSIG_BPW]	\
85 					& (1L << ((n) - 1) % LINUX__NSIG_BPW))
86 #define	linux_sigaddset(s, n)	((s)->sig[((n) - 1) / LINUX__NSIG_BPW]	\
87 					|= (1L << ((n) - 1) % LINUX__NSIG_BPW))
88 
89 #ifdef DEBUG_LINUX
90 #define DPRINTF(a)	uprintf a
91 #else
92 #define DPRINTF(a)
93 #endif
94 
95 extern const int native_to_linux_signo[];
96 extern const int linux_to_native_signo[];
97 
98 /*
99  * Convert between Linux and BSD signal sets.
100  */
101 #if LINUX__NSIG_WORDS > 1
102 void
103 linux_old_extra_to_native_sigset(sigset_t *bss, const linux_old_sigset_t *lss, const unsigned long *extra)
104 {
105 	linux_sigset_t lsnew;
106 
107 	/* convert old sigset to new sigset */
108 	linux_sigemptyset(&lsnew);
109 	lsnew.sig[0] = *lss;
110 	if (extra)
111 		memcpy(&lsnew.sig[1], extra,
112 		    sizeof(linux_sigset_t) - sizeof(linux_old_sigset_t));
113 
114 	linux_to_native_sigset(bss, &lsnew);
115 }
116 
117 void
118 native_to_linux_old_extra_sigset(linux_old_sigset_t *lss, unsigned long *extra, const sigset_t *bss)
119 {
120 	linux_sigset_t lsnew;
121 
122 	native_to_linux_sigset(&lsnew, bss);
123 
124 	/* convert new sigset to old sigset */
125 	*lss = lsnew.sig[0];
126 	if (extra)
127 		memcpy(extra, &lsnew.sig[1],
128 		    sizeof(linux_sigset_t) - sizeof(linux_old_sigset_t));
129 }
130 #endif /* LINUX__NSIG_WORDS > 1 */
131 
132 void
133 linux_to_native_sigset(sigset_t *bss, const linux_sigset_t *lss)
134 {
135 	int i, newsig;
136 
137 	sigemptyset(bss);
138 	for (i = 1; i < LINUX__NSIG; i++) {
139 		if (linux_sigismember(lss, i)) {
140 			newsig = linux_to_native_signo[i];
141 			if (newsig)
142 				sigaddset(bss, newsig);
143 		}
144 	}
145 }
146 
147 void
148 native_to_linux_sigset(linux_sigset_t *lss, const sigset_t *bss)
149 {
150 	int i, newsig;
151 
152 	linux_sigemptyset(lss);
153 	for (i = 1; i < NSIG; i++) {
154 		if (sigismember(bss, i)) {
155 			newsig = native_to_linux_signo[i];
156 			if (newsig)
157 				linux_sigaddset(lss, newsig);
158 		}
159 	}
160 }
161 
162 void
163 native_to_linux_siginfo(linux_siginfo_t *lsi, const struct _ksiginfo *ksi)
164 {
165 	memset(lsi, 0, sizeof(*lsi));
166 
167 	lsi->lsi_signo = native_to_linux_signo[ksi->_signo];
168 	lsi->lsi_errno = native_to_linux_errno[ksi->_errno];
169 	lsi->lsi_code = native_to_linux_si_code(ksi->_code);
170 
171 	switch (ksi->_code) {
172 	case SI_NOINFO:
173 		break;
174 
175 	case SI_USER:
176 		lsi->lsi_pid = ksi->_reason._rt._pid;
177 		lsi->lsi_uid = ksi->_reason._rt._uid;
178 		if (lsi->lsi_signo == LINUX_SIGALRM ||
179 		    lsi->lsi_signo >= LINUX_SIGRTMIN)
180 			lsi->lsi_value.sival_ptr =
181 			    ksi->_reason._rt._value.sival_ptr;
182 		break;
183 
184 	case SI_TIMER:
185 	case SI_QUEUE:
186 		lsi->lsi_uid = ksi->_reason._rt._uid;
187 		lsi->lsi_uid = ksi->_reason._rt._uid;
188 		lsi->lsi_value.sival_ptr = ksi->_reason._rt._value.sival_ptr;
189 		break;
190 
191 	case SI_ASYNCIO:
192 	case SI_MESGQ:
193 		lsi->lsi_value.sival_ptr = ksi->_reason._rt._value.sival_ptr;
194 		break;
195 
196 	default:
197 		switch (ksi->_signo) {
198 		case SIGCHLD:
199 			lsi->lsi_uid = ksi->_reason._child._uid;
200 			lsi->lsi_pid = ksi->_reason._child._pid;
201 			lsi->lsi_status = native_to_linux_si_status(
202 			    ksi->_code, ksi->_reason._child._status);
203 			lsi->lsi_utime = ksi->_reason._child._utime;
204 			lsi->lsi_stime = ksi->_reason._child._stime;
205 			break;
206 
207 		case SIGILL:
208 		case SIGFPE:
209 		case SIGSEGV:
210 		case SIGBUS:
211 		case SIGTRAP:
212 			lsi->lsi_addr = ksi->_reason._fault._addr;
213 			break;
214 
215 		case SIGIO:
216 			lsi->lsi_fd = ksi->_reason._poll._fd;
217 			lsi->lsi_band = ksi->_reason._poll._band;
218 			break;
219 		default:
220 			break;
221 		}
222 	}
223 }
224 
225 unsigned int
226 native_to_linux_sigflags(const int bsf)
227 {
228 	unsigned int lsf = 0;
229 	if ((bsf & SA_NOCLDSTOP) != 0)
230 		lsf |= LINUX_SA_NOCLDSTOP;
231 	if ((bsf & SA_NOCLDWAIT) != 0)
232 		lsf |= LINUX_SA_NOCLDWAIT;
233 	if ((bsf & SA_ONSTACK) != 0)
234 		lsf |= LINUX_SA_ONSTACK;
235 	if ((bsf & SA_RESTART) != 0)
236 		lsf |= LINUX_SA_RESTART;
237 	if ((bsf & SA_NODEFER) != 0)
238 		lsf |= LINUX_SA_NOMASK;
239 	if ((bsf & SA_RESETHAND) != 0)
240 		lsf |= LINUX_SA_ONESHOT;
241 	if ((bsf & SA_SIGINFO) != 0)
242 		lsf |= LINUX_SA_SIGINFO;
243 	return lsf;
244 }
245 
246 int
247 linux_to_native_sigflags(const unsigned long lsf)
248 {
249 	int bsf = 0;
250 	if ((lsf & LINUX_SA_NOCLDSTOP) != 0)
251 		bsf |= SA_NOCLDSTOP;
252 	if ((lsf & LINUX_SA_NOCLDWAIT) != 0)
253 		bsf |= SA_NOCLDWAIT;
254 	if ((lsf & LINUX_SA_ONSTACK) != 0)
255 		bsf |= SA_ONSTACK;
256 	if ((lsf & LINUX_SA_RESTART) != 0)
257 		bsf |= SA_RESTART;
258 	if ((lsf & LINUX_SA_ONESHOT) != 0)
259 		bsf |= SA_RESETHAND;
260 	if ((lsf & LINUX_SA_NOMASK) != 0)
261 		bsf |= SA_NODEFER;
262 	if ((lsf & LINUX_SA_SIGINFO) != 0)
263 		bsf |= SA_SIGINFO;
264 	if ((lsf & ~LINUX_SA_ALLBITS) != 0) {
265 		DPRINTF(("linux_old_to_native_sigflags: "
266 		    "%lx extra bits ignored\n", lsf));
267 	}
268 	return bsf;
269 }
270 
271 /*
272  * Convert between Linux and BSD sigaction structures.
273  */
274 void
275 linux_old_to_native_sigaction(struct sigaction *bsa, const struct linux_old_sigaction *lsa)
276 {
277 	bsa->sa_handler = lsa->linux_sa_handler;
278 	linux_old_to_native_sigset(&bsa->sa_mask, &lsa->linux_sa_mask);
279 	bsa->sa_flags = linux_to_native_sigflags(lsa->linux_sa_flags);
280 }
281 
282 void
283 native_to_linux_old_sigaction(struct linux_old_sigaction *lsa, const struct sigaction *bsa)
284 {
285 	lsa->linux_sa_handler = bsa->sa_handler;
286 	native_to_linux_old_sigset(&lsa->linux_sa_mask, &bsa->sa_mask);
287 	lsa->linux_sa_flags = native_to_linux_sigflags(bsa->sa_flags);
288 #ifndef __alpha__
289 	lsa->linux_sa_restorer = NULL;
290 #endif
291 }
292 
293 /* ...and the new sigaction conversion funcs. */
294 void
295 linux_to_native_sigaction(struct sigaction *bsa, const struct linux_sigaction *lsa)
296 {
297 	bsa->sa_handler = lsa->linux_sa_handler;
298 	linux_to_native_sigset(&bsa->sa_mask, &lsa->linux_sa_mask);
299 	bsa->sa_flags = linux_to_native_sigflags(lsa->linux_sa_flags);
300 }
301 
302 void
303 native_to_linux_sigaction(struct linux_sigaction *lsa, const struct sigaction *bsa)
304 {
305 	lsa->linux_sa_handler = bsa->sa_handler;
306 	native_to_linux_sigset(&lsa->linux_sa_mask, &bsa->sa_mask);
307 	lsa->linux_sa_flags = native_to_linux_sigflags(bsa->sa_flags);
308 #ifndef __alpha__
309 	lsa->linux_sa_restorer = NULL;
310 #endif
311 }
312 
313 /* ----------------------------------------------------------------------- */
314 
315 /*
316  * The Linux sigaction() system call. Do the usual conversions,
317  * and just call sigaction(). Some flags and values are silently
318  * ignored (see above).
319  */
320 int
321 linux_sys_rt_sigaction(struct lwp *l, const struct linux_sys_rt_sigaction_args *uap, register_t *retval)
322 {
323 	/* {
324 		syscallarg(int) signum;
325 		syscallarg(const struct linux_sigaction *) nsa;
326 		syscallarg(struct linux_sigaction *) osa;
327 		syscallarg(size_t) sigsetsize;
328 	} */
329 	struct linux_sigaction nlsa, olsa;
330 	struct sigaction nbsa, obsa;
331 	int error, sig;
332 	void *tramp = NULL;
333 	int vers = 0;
334 #ifdef LINUX_SA_RESTORER
335 	struct sigacts *ps = l->l_proc->p_sigacts;
336 #endif
337 
338 	if (SCARG(uap, sigsetsize) != sizeof(linux_sigset_t))
339 		return EINVAL;
340 
341 	if (SCARG(uap, nsa)) {
342 		error = copyin(SCARG(uap, nsa), &nlsa, sizeof(nlsa));
343 		if (error)
344 			return error;
345 		linux_to_native_sigaction(&nbsa, &nlsa);
346 	}
347 
348 	sig = SCARG(uap, signum);
349 	/*
350 	 * XXX: Linux has 33 realtime signals, the go binary wants to
351 	 * reset all of them; nothing else uses the last RT signal, so for
352 	 * now ignore it.
353 	 */
354 	if (sig == LINUX__NSIG) {
355 		uprintf("%s: setting signal %d ignored\n", __func__, sig);
356 		sig--;	/* back to 63 which is ignored */
357 	}
358 	if (sig < 0 || sig >= LINUX__NSIG)
359 		return EINVAL;
360 	if (sig > 0 && !linux_to_native_signo[sig]) {
361 		/* Pretend that we did something useful for unknown signals. */
362 		obsa.sa_handler = SIG_IGN;
363 		sigemptyset(&obsa.sa_mask);
364 		obsa.sa_flags = 0;
365 	} else {
366 #ifdef LINUX_SA_RESTORER
367 		if (SCARG(uap, nsa) &&
368 		    (nlsa.linux_sa_flags & LINUX_SA_RESTORER) &&
369 		    (tramp = nlsa.linux_sa_restorer) != NULL)
370 			vers = 2;
371 #endif
372 
373 		error = sigaction1(l, linux_to_native_signo[sig],
374 		    SCARG(uap, nsa) ? &nbsa : NULL,
375 		    SCARG(uap, osa) ? &obsa : NULL,
376 		    tramp, vers);
377 		if (error)
378 			return error;
379 	}
380 	if (SCARG(uap, osa)) {
381 		native_to_linux_sigaction(&olsa, &obsa);
382 
383 #ifdef LINUX_SA_RESTORER
384 		if (ps->sa_sigdesc[sig].sd_vers != 0) {
385 			olsa.linux_sa_restorer = ps->sa_sigdesc[sig].sd_tramp;
386 			olsa.linux_sa_flags |= LINUX_SA_RESTORER;
387 		}
388 #endif
389 
390 		error = copyout(&olsa, SCARG(uap, osa), sizeof(olsa));
391 		if (error)
392 			return error;
393 	}
394 	return 0;
395 }
396 
397 int
398 linux_sigprocmask1(struct lwp *l, int how, const linux_old_sigset_t *set, linux_old_sigset_t *oset)
399 {
400 	struct proc *p = l->l_proc;
401 	linux_old_sigset_t nlss, olss;
402 	sigset_t nbss, obss;
403 	int error;
404 
405 	switch (how) {
406 	case LINUX_SIG_BLOCK:
407 		how = SIG_BLOCK;
408 		break;
409 	case LINUX_SIG_UNBLOCK:
410 		how = SIG_UNBLOCK;
411 		break;
412 	case LINUX_SIG_SETMASK:
413 		how = SIG_SETMASK;
414 		break;
415 	default:
416 		return EINVAL;
417 	}
418 
419 	if (set) {
420 		error = copyin(set, &nlss, sizeof(nlss));
421 		if (error)
422 			return error;
423 		linux_old_to_native_sigset(&nbss, &nlss);
424 	}
425 	mutex_enter(p->p_lock);
426 	error = sigprocmask1(l, how,
427 	    set ? &nbss : NULL, oset ? &obss : NULL);
428 	mutex_exit(p->p_lock);
429 	if (error)
430 		return error;
431 	if (oset) {
432 		native_to_linux_old_sigset(&olss, &obss);
433 		error = copyout(&olss, oset, sizeof(olss));
434 		if (error)
435 			return error;
436 	}
437 	return error;
438 }
439 
440 int
441 linux_sys_rt_sigprocmask(struct lwp *l, const struct linux_sys_rt_sigprocmask_args *uap, register_t *retval)
442 {
443 	/* {
444 		syscallarg(int) how;
445 		syscallarg(const linux_sigset_t *) set;
446 		syscallarg(linux_sigset_t *) oset;
447 		syscallarg(size_t) sigsetsize;
448 	} */
449 	linux_sigset_t nlss, olss, *oset;
450 	const linux_sigset_t *set;
451 	struct proc *p = l->l_proc;
452 	sigset_t nbss, obss;
453 	int error, how;
454 
455 	if (SCARG(uap, sigsetsize) != sizeof(linux_sigset_t))
456 		return EINVAL;
457 
458 	switch (SCARG(uap, how)) {
459 	case LINUX_SIG_BLOCK:
460 		how = SIG_BLOCK;
461 		break;
462 	case LINUX_SIG_UNBLOCK:
463 		how = SIG_UNBLOCK;
464 		break;
465 	case LINUX_SIG_SETMASK:
466 		how = SIG_SETMASK;
467 		break;
468 	default:
469 		return EINVAL;
470 	}
471 
472 	set = SCARG(uap, set);
473 	oset = SCARG(uap, oset);
474 
475 	if (set) {
476 		error = copyin(set, &nlss, sizeof(nlss));
477 		if (error)
478 			return error;
479 		linux_to_native_sigset(&nbss, &nlss);
480 	}
481 	mutex_enter(p->p_lock);
482 	error = sigprocmask1(l, how,
483 	    set ? &nbss : NULL, oset ? &obss : NULL);
484 	mutex_exit(p->p_lock);
485 	if (!error && oset) {
486 		native_to_linux_sigset(&olss, &obss);
487 		error = copyout(&olss, oset, sizeof(olss));
488 	}
489 	return error;
490 }
491 
492 int
493 linux_sys_rt_sigpending(struct lwp *l, const struct linux_sys_rt_sigpending_args *uap, register_t *retval)
494 {
495 	/* {
496 		syscallarg(linux_sigset_t *) set;
497 		syscallarg(size_t) sigsetsize;
498 	} */
499 	sigset_t bss;
500 	linux_sigset_t lss;
501 
502 	if (SCARG(uap, sigsetsize) != sizeof(linux_sigset_t))
503 		return EINVAL;
504 
505 	sigpending1(l, &bss);
506 	native_to_linux_sigset(&lss, &bss);
507 	return copyout(&lss, SCARG(uap, set), sizeof(lss));
508 }
509 
510 #ifndef __amd64__
511 int
512 linux_sys_sigpending(struct lwp *l, const struct linux_sys_sigpending_args *uap, register_t *retval)
513 {
514 	/* {
515 		syscallarg(linux_old_sigset_t *) mask;
516 	} */
517 	sigset_t bss;
518 	linux_old_sigset_t lss;
519 
520 	sigpending1(l, &bss);
521 	native_to_linux_old_sigset(&lss, &bss);
522 	return copyout(&lss, SCARG(uap, set), sizeof(lss));
523 }
524 
525 int
526 linux_sys_sigsuspend(struct lwp *l, const struct linux_sys_sigsuspend_args *uap, register_t *retval)
527 {
528 	/* {
529 		syscallarg(void *) restart;
530 		syscallarg(int) oldmask;
531 		syscallarg(int) mask;
532 	} */
533 	linux_old_sigset_t lss;
534 	sigset_t bss;
535 
536 	lss = SCARG(uap, mask);
537 	linux_old_to_native_sigset(&bss, &lss);
538 	return sigsuspend1(l, &bss);
539 }
540 #endif /* __amd64__ */
541 
542 int
543 linux_sys_rt_sigsuspend(struct lwp *l, const struct linux_sys_rt_sigsuspend_args *uap, register_t *retval)
544 {
545 	/* {
546 		syscallarg(linux_sigset_t *) unewset;
547 		syscallarg(size_t) sigsetsize;
548 	} */
549 	linux_sigset_t lss;
550 	sigset_t bss;
551 	int error;
552 
553 	if (SCARG(uap, sigsetsize) != sizeof(linux_sigset_t))
554 		return EINVAL;
555 
556 	error = copyin(SCARG(uap, unewset), &lss, sizeof(linux_sigset_t));
557 	if (error)
558 		return error;
559 
560 	linux_to_native_sigset(&bss, &lss);
561 
562 	return sigsuspend1(l, &bss);
563 }
564 
565 static int
566 fetchss(const void *u, void *s, size_t len)
567 {
568 	int error;
569 	linux_sigset_t lss;
570 
571 	if ((error = copyin(u, &lss, sizeof(lss))) != 0)
572 		return error;
573 
574 	linux_to_native_sigset(s, &lss);
575 	return 0;
576 }
577 
578 static int
579 fetchts(const void *u, void *s, size_t len)
580 {
581 	int error;
582 	struct linux_timespec lts;
583 
584 	if ((error = copyin(u, &lts, sizeof(lts))) != 0)
585 		return error;
586 
587 	linux_to_native_timespec(s, &lts);
588 	return 0;
589 }
590 
591 static int
592 fakestorets(const void *u, void *s, size_t len)
593 {
594 	/* Do nothing, sigtimedwait does not alter timeout like ours */
595 	return 0;
596 }
597 
598 static int
599 storeinfo(const void *s, void *u, size_t len)
600 {
601 	struct linux_siginfo lsi;
602 
603 	native_to_linux_siginfo(&lsi, &((const siginfo_t *)s)->_info);
604 	return copyout(&lsi, u, sizeof(lsi));
605 }
606 
607 int
608 linux_sys_rt_sigtimedwait(struct lwp *l,
609     const struct linux_sys_rt_sigtimedwait_args *uap, register_t *retval)
610 {
611 	/* {
612 		syscallarg(const linux_sigset_t *) set;
613 		syscallarg(linux_siginfo_t *) info);
614 		syscallarg(const struct linux_timespec *) timeout;
615 	} */
616 
617 	return sigtimedwait1(l, (const struct sys_____sigtimedwait50_args *)uap,
618 	    retval, fetchss, storeinfo, fetchts, fakestorets);
619 }
620 
621 /*
622  * Once more: only a signal conversion is needed.
623  * Note: also used as sys_rt_queueinfo.  The info field is ignored.
624  */
625 int
626 linux_sys_rt_queueinfo(struct lwp *l, const struct linux_sys_rt_queueinfo_args *uap, register_t *retval)
627 {
628 	/*
629 		syscallarg(int) pid;
630 		syscallarg(int) signum;
631 		syscallarg(linix_siginfo_t *) uinfo;
632 	*/
633 	int error;
634 	linux_siginfo_t info;
635 
636 	error = copyin(SCARG(uap, uinfo), &info, sizeof(info));
637 	if (error)
638 		return error;
639 	if (info.lsi_code >= 0)
640 		return EPERM;
641 
642 	/* XXX To really implement this we need to	*/
643 	/* XXX keep a list of queued signals somewhere.	*/
644 	return linux_sys_kill(l, (const void *)uap, retval);
645 }
646 
647 int
648 linux_sys_kill(struct lwp *l, const struct linux_sys_kill_args *uap, register_t *retval)
649 {
650 	/* {
651 		syscallarg(int) pid;
652 		syscallarg(int) signum;
653 	} */
654 
655 	struct sys_kill_args ka;
656 	int sig;
657 
658 	SCARG(&ka, pid) = SCARG(uap, pid);
659 	sig = SCARG(uap, signum);
660 	if (sig < 0 || sig >= LINUX__NSIG)
661 		return EINVAL;
662 	SCARG(&ka, signum) = linux_to_native_signo[sig];
663 	return sys_kill(l, &ka, retval);
664 }
665 
666 #ifdef LINUX_SS_ONSTACK
667 static void linux_to_native_sigaltstack(struct sigaltstack *,
668     const struct linux_sigaltstack *);
669 
670 static void
671 linux_to_native_sigaltstack(struct sigaltstack *bss, const struct linux_sigaltstack *lss)
672 {
673 	bss->ss_sp = lss->ss_sp;
674 	bss->ss_size = lss->ss_size;
675 	if (lss->ss_flags & LINUX_SS_ONSTACK)
676 	    bss->ss_flags = SS_ONSTACK;
677 	else if (lss->ss_flags & LINUX_SS_DISABLE)
678 	    bss->ss_flags = SS_DISABLE;
679 	else
680 	    bss->ss_flags = 0;
681 }
682 
683 void
684 native_to_linux_sigaltstack(struct linux_sigaltstack *lss, const struct sigaltstack *bss)
685 {
686 	lss->ss_sp = bss->ss_sp;
687 	lss->ss_size = bss->ss_size;
688 	if (bss->ss_flags & SS_ONSTACK)
689 	    lss->ss_flags = LINUX_SS_ONSTACK;
690 	else if (bss->ss_flags & SS_DISABLE)
691 	    lss->ss_flags = LINUX_SS_DISABLE;
692 	else
693 	    lss->ss_flags = 0;
694 }
695 
696 int
697 linux_sys_sigaltstack(struct lwp *l, const struct linux_sys_sigaltstack_args *uap, register_t *retval)
698 {
699 	/* {
700 		syscallarg(const struct linux_sigaltstack *) ss;
701 		syscallarg(struct linux_sigaltstack *) oss;
702 	} */
703 	struct linux_sigaltstack ss;
704 	struct sigaltstack nss;
705 	struct proc *p = l->l_proc;
706 	int error = 0;
707 
708 	if (SCARG(uap, oss)) {
709 		native_to_linux_sigaltstack(&ss, &l->l_sigstk);
710 		if ((error = copyout(&ss, SCARG(uap, oss), sizeof(ss))) != 0)
711 			return error;
712 	}
713 
714 	if (SCARG(uap, ss) != NULL) {
715 		if ((error = copyin(SCARG(uap, ss), &ss, sizeof(ss))) != 0)
716 			return error;
717 		linux_to_native_sigaltstack(&nss, &ss);
718 
719 		mutex_enter(p->p_lock);
720 
721 		if (nss.ss_flags & ~SS_ALLBITS)
722 			error = EINVAL;
723 		else if (nss.ss_flags & SS_DISABLE) {
724 			if (l->l_sigstk.ss_flags & SS_ONSTACK)
725 				error = EINVAL;
726 		} else if (nss.ss_size < LINUX_MINSIGSTKSZ)
727 			error = ENOMEM;
728 
729 		if (error == 0)
730 			l->l_sigstk = nss;
731 
732 		mutex_exit(p->p_lock);
733 	}
734 
735 	return error;
736 }
737 #endif /* LINUX_SS_ONSTACK */
738 
739 static int
740 linux_do_tkill(struct lwp *l, int tgid, int tid, int signum)
741 {
742 	struct proc *p;
743 	struct lwp *t;
744 	ksiginfo_t ksi;
745 	int error;
746 
747 	if (signum < 0 || signum >= LINUX__NSIG)
748 		return EINVAL;
749 	signum = linux_to_native_signo[signum];
750 
751 	if (tgid == -1) {
752 		tgid = tid;
753 	}
754 
755 	KSI_INIT(&ksi);
756 	ksi.ksi_signo = signum;
757 	ksi.ksi_code = SI_LWP;
758 	ksi.ksi_pid = l->l_proc->p_pid;
759 	ksi.ksi_uid = kauth_cred_geteuid(l->l_cred);
760 	ksi.ksi_lid = tid;
761 
762 	mutex_enter(proc_lock);
763 	p = proc_find(tgid);
764 	if (p == NULL) {
765 		mutex_exit(proc_lock);
766 		return ESRCH;
767 	}
768 	mutex_enter(p->p_lock);
769 	error = kauth_authorize_process(l->l_cred,
770 	    KAUTH_PROCESS_SIGNAL, p, KAUTH_ARG(signum), NULL, NULL);
771 	if ((t = lwp_find(p, ksi.ksi_lid)) == NULL)
772 		error = ESRCH;
773 	else if (signum != 0)
774 		kpsignal2(p, &ksi);
775 	mutex_exit(p->p_lock);
776 	mutex_exit(proc_lock);
777 
778 	return error;
779 }
780 
781 int
782 linux_sys_tkill(struct lwp *l, const struct linux_sys_tkill_args *uap, register_t *retval)
783 {
784 	/* {
785 		syscallarg(int) tid;
786 		syscallarg(int) sig;
787 	} */
788 
789 	if (SCARG(uap, tid) <= 0)
790 		return EINVAL;
791 
792 	return linux_do_tkill(l, -1, SCARG(uap, tid), SCARG(uap, sig));
793 }
794 
795 int
796 linux_sys_tgkill(struct lwp *l, const struct linux_sys_tgkill_args *uap, register_t *retval)
797 {
798 	/* {
799 		syscallarg(int) tgid;
800 		syscallarg(int) tid;
801 		syscallarg(int) sig;
802 	} */
803 
804 	if (SCARG(uap, tid) <= 0 || SCARG(uap, tgid) < -1)
805 		return EINVAL;
806 
807 	return linux_do_tkill(l, SCARG(uap, tgid), SCARG(uap, tid), SCARG(uap, sig));
808 }
809 
810 int
811 native_to_linux_si_code(int code)
812 {
813 	int si_codes[] = {
814 	    LINUX_SI_USER, LINUX_SI_QUEUE, LINUX_SI_TIMER, LINUX_SI_ASYNCIO,
815 	    LINUX_SI_MESGQ, LINUX_SI_TKILL /* SI_LWP */
816 	};
817 
818 	if (code <= 0 && -code < __arraycount(si_codes))
819 		return si_codes[-code];
820 
821 	return code;
822 }
823 
824 int
825 native_to_linux_si_status(int code, int status)
826 {
827 	int sts;
828 
829 	switch (code) {
830 	case CLD_CONTINUED:
831 		sts = LINUX_SIGCONT;
832 		break;
833 	case CLD_EXITED:
834 		sts = WEXITSTATUS(status);
835 		break;
836 	case CLD_STOPPED:
837 	case CLD_TRAPPED:
838 	case CLD_DUMPED:
839 	case CLD_KILLED:
840 	default:
841 		sts = native_to_linux_signo[WTERMSIG(status)];
842 		break;
843 	}
844 
845 	return sts;
846 }
847