14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2015 Joyent, Inc.
24 */
25 /*
26 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 /* Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
31 /* Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T */
32 /* All Rights Reserved */
33
34 #include <sys/types.h>
35 #include <sys/param.h>
36 #include <sys/sysmacros.h>
37 #include <sys/signal.h>
38 #include <sys/systm.h>
39 #include <sys/user.h>
40 #include <sys/mman.h>
41 #include <sys/class.h>
42 #include <sys/proc.h>
43 #include <sys/procfs.h>
44 #include <sys/buf.h>
45 #include <sys/kmem.h>
46 #include <sys/cred.h>
47 #include <sys/archsystm.h>
48 #include <sys/vmparam.h>
49 #include <sys/prsystm.h>
50 #include <sys/reboot.h>
51 #include <sys/uadmin.h>
52 #include <sys/vfs.h>
53 #include <sys/vnode.h>
95
96 /*
97 * Construct the execution environment for the user's signal
98 * handler and arrange for control to be given to it on return
99 * to userland. The library code now calls setcontext() to
100 * clean up after the signal handler, so sigret() is no longer
101 * needed.
102 *
103 * (The various 'volatile' declarations are need to ensure that values
104 * are correct on the error return from on_fault().)
105 */
106
107
108 /*
109 * An amd64 signal frame looks like this on the stack:
110 *
111 * old %rsp:
112 * <128 bytes of untouched stack space>
113 * <a siginfo_t [optional]>
114 * <a ucontext_t>
115 * <siginfo_t *>
116 * <signal number>
117 * new %rsp: <return address (deliberately invalid)>
118 *
119 * The signal number and siginfo_t pointer are only pushed onto the stack in
120 * order to allow stack backtraces. The actual signal handling code expects the
121 * arguments in registers.
122 */
123
124 struct sigframe {
125 caddr_t retaddr;
126 long signo;
127 siginfo_t *sip;
128 };
129
130 int
131 sendsig(int sig, k_siginfo_t *sip, void (*hdlr)())
132 {
133 volatile int minstacksz;
134 int newstack;
135 label_t ljb;
136 volatile caddr_t sp;
137 caddr_t fp;
138 volatile struct regs *rp;
139 volatile greg_t upc;
140 volatile proc_t *p = ttoproc(curthread);
141 struct as *as = p->p_as;
142 klwp_t *lwp = ttolwp(curthread);
143 ucontext_t *volatile tuc = NULL;
144 ucontext_t *uc;
145 siginfo_t *sip_addr;
146 volatile int watched;
147
148 /*
149 * This routine is utterly dependent upon STACK_ALIGN being
150 * 16 and STACK_ENTRY_ALIGN being 8. Let's just acknowledge
151 * that and require it.
152 */
153
154 #if STACK_ALIGN != 16 || STACK_ENTRY_ALIGN != 8
155 #error "sendsig() amd64 did not find the expected stack alignments"
156 #endif
157
158 rp = lwptoregs(lwp);
159 upc = rp->r_pc;
160
161 /*
162 * Since we're setting up to run the signal handler we have to
163 * arrange that the stack at entry to the handler is (only)
164 * STACK_ENTRY_ALIGN (i.e. 8) byte aligned so that when the handler
165 * executes its push of %rbp, the stack realigns to STACK_ALIGN
166 * (i.e. 16) correctly.
167 *
168 * The new sp will point to the sigframe and the ucontext_t. The
169 * above means that sp (and thus sigframe) will be 8-byte aligned,
170 * but not 16-byte aligned. ucontext_t, however, contains %xmm regs
171 * which must be 16-byte aligned. Because of this, for correct
172 * alignment, sigframe must be a multiple of 8-bytes in length, but
173 * not 16-bytes. This will place ucontext_t at a nice 16-byte boundary.
174 */
175
176 /* LINTED: logical expression always true: op "||" */
177 ASSERT((sizeof (struct sigframe) % 16) == 8);
178
179 minstacksz = sizeof (struct sigframe) + SA(sizeof (*uc));
180 if (sip != NULL)
181 minstacksz += SA(sizeof (siginfo_t));
182 ASSERT((minstacksz & (STACK_ENTRY_ALIGN - 1ul)) == 0);
183
184 /*
185 * Figure out whether we will be handling this signal on
186 * an alternate stack specified by the user. Then allocate
187 * and validate the stack requirements for the signal handler
188 * context. on_fault will catch any faults.
189 */
190 newstack = sigismember(&PTOU(curproc)->u_sigonstack, sig) &&
191 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE));
192
193 /*
194 * If this is a branded process, the brand may provide an alternate
195 * stack pointer for signal delivery:
196 */
197 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig_stack != NULL) {
198 /*
199 * Use the stack pointer value provided by the brand,
200 * accounting for the 128-byte reserved region.
201 */
278 curthread->t_rprof->rp_anystate) {
279 /*
280 * We stand on our head to deal with
281 * the real time profiling signal.
282 * Fill in the stuff that doesn't fit
283 * in a normal k_siginfo structure.
284 */
285 int i = sip->si_nsysarg;
286
287 while (--i >= 0)
288 sulword_noerr(
289 (ulong_t *)&(sip_addr->si_sysarg[i]),
290 (ulong_t)lwp->lwp_arg[i]);
291 copyout_noerr(curthread->t_rprof->rp_state,
292 sip_addr->si_mstate,
293 sizeof (curthread->t_rprof->rp_state));
294 }
295 } else
296 sip_addr = NULL;
297
298 /*
299 * save the current context on the user stack directly after the
300 * sigframe. Since sigframe is 8-byte-but-not-16-byte aligned,
301 * and since sizeof (struct sigframe) is 24, this guarantees
302 * 16-byte alignment for ucontext_t and its %xmm registers.
303 */
304 uc = (ucontext_t *)(sp + sizeof (struct sigframe));
305 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP);
306 no_fault();
307 savecontext(tuc, &lwp->lwp_sigoldmask);
308 if (on_fault(&ljb))
309 goto badstack;
310 copyout_noerr(tuc, uc, sizeof (*tuc));
311 kmem_free(tuc, sizeof (*tuc));
312 tuc = NULL;
313
314 DTRACE_PROBE3(oldcontext__set, klwp_t *, lwp,
315 uintptr_t, lwp->lwp_oldcontext, uintptr_t, (uintptr_t)uc);
316 lwp->lwp_oldcontext = (uintptr_t)uc;
317
318 if (newstack) {
319 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK;
320 if (lwp->lwp_ustack)
321 copyout_noerr(&lwp->lwp_sigaltstack,
322 (stack_t *)lwp->lwp_ustack, sizeof (stack_t));
323 }
324
325 /*
326 * Set up signal handler return and stack linkage
327 */
361 rp->r_ss = UDS_SEL;
362 }
363
364 /*
365 * Allow the brand to perform additional book-keeping once the signal
366 * handling frame has been fully assembled:
367 */
368 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig != NULL) {
369 BROP(p)->b_sendsig(sig);
370 }
371
372 /*
373 * Don't set lwp_eosys here. sendsig() is called via psig() after
374 * lwp_eosys is handled, so setting it here would affect the next
375 * system call.
376 */
377 return (1);
378
379 badstack:
380 no_fault();
381 if (watched)
382 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE);
383 if (tuc)
384 kmem_free(tuc, sizeof (*tuc));
385 #ifdef DEBUG
386 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n",
387 PTOU(p)->u_comm, p->p_pid, sig);
388 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n",
389 (void *)sp, (void *)hdlr, (uintptr_t)upc);
390 #endif
391 return (0);
392 }
393
394 #ifdef _SYSCALL32_IMPL
395
396 /*
397 * An i386 SVR4/ABI signal frame looks like this on the stack:
398 *
399 * old %esp:
400 * <a siginfo32_t [optional]>
401 * <a ucontext32_t>
402 * <pointer to that ucontext32_t>
403 * <pointer to that siginfo32_t>
404 * <signo>
405 * new %esp: <return address (deliberately invalid)>
406 */
407 struct sigframe32 {
408 caddr32_t retaddr;
409 uint32_t signo;
410 caddr32_t sip;
411 caddr32_t ucp;
412 };
413
414 int
415 sendsig32(int sig, k_siginfo_t *sip, void (*hdlr)())
416 {
417 volatile int minstacksz;
418 int newstack;
419 label_t ljb;
420 volatile caddr_t sp;
421 caddr_t fp;
422 volatile struct regs *rp;
423 volatile greg_t upc;
424 volatile proc_t *p = ttoproc(curthread);
425 klwp_t *lwp = ttolwp(curthread);
426 ucontext32_t *volatile tuc = NULL;
427 ucontext32_t *uc;
428 siginfo32_t *sip_addr;
429 volatile int watched;
430
431 rp = lwptoregs(lwp);
432 upc = rp->r_pc;
433
434 minstacksz = SA32(sizeof (struct sigframe32)) + SA32(sizeof (*uc));
435 if (sip != NULL)
436 minstacksz += SA32(sizeof (siginfo32_t));
437 ASSERT((minstacksz & (STACK_ALIGN32 - 1)) == 0);
438
439 /*
440 * Figure out whether we will be handling this signal on
441 * an alternate stack specified by the user. Then allocate
442 * and validate the stack requirements for the signal handler
443 * context. on_fault will catch any faults.
444 */
445 newstack = sigismember(&PTOU(curproc)->u_sigonstack, sig) &&
446 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE));
447
448 /*
449 * If this is a branded process, the brand may provide an alternate
450 * stack pointer for signal delivery:
451 */
452 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig_stack != NULL) {
453 /*
454 * Use the stack pointer value provided by the brand:
455 */
456 newstack = 0;
523 if (sig == SIGPROF &&
524 curthread->t_rprof != NULL &&
525 curthread->t_rprof->rp_anystate) {
526 /*
527 * We stand on our head to deal with
528 * the real-time profiling signal.
529 * Fill in the stuff that doesn't fit
530 * in a normal k_siginfo structure.
531 */
532 int i = sip->si_nsysarg;
533
534 while (--i >= 0)
535 suword32_noerr(&(sip_addr->si_sysarg[i]),
536 (uint32_t)lwp->lwp_arg[i]);
537 copyout_noerr(curthread->t_rprof->rp_state,
538 sip_addr->si_mstate,
539 sizeof (curthread->t_rprof->rp_state));
540 }
541 } else
542 sip_addr = NULL;
543
544 /* save the current context on the user stack */
545 fp -= SA32(sizeof (*tuc));
546 uc = (ucontext32_t *)fp;
547 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP);
548 no_fault();
549 savecontext32(tuc, &lwp->lwp_sigoldmask);
550 if (on_fault(&ljb))
551 goto badstack;
552 copyout_noerr(tuc, uc, sizeof (*tuc));
553 kmem_free(tuc, sizeof (*tuc));
554 tuc = NULL;
555
556 DTRACE_PROBE3(oldcontext__set, klwp_t *, lwp,
557 uintptr_t, lwp->lwp_oldcontext, uintptr_t, (uintptr_t)uc);
558 lwp->lwp_oldcontext = (uintptr_t)uc;
559
560 if (newstack) {
561 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK;
562 if (lwp->lwp_ustack) {
563 stack32_t stk32;
564
565 stk32.ss_sp = (caddr32_t)(uintptr_t)
566 lwp->lwp_sigaltstack.ss_sp;
567 stk32.ss_size = (size32_t)
568 lwp->lwp_sigaltstack.ss_size;
569 stk32.ss_flags = (int32_t)
603 rp->r_ss = UDS_SEL;
604 }
605
606 /*
607 * Allow the brand to perform additional book-keeping once the signal
608 * handling frame has been fully assembled:
609 */
610 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig != NULL) {
611 BROP(p)->b_sendsig(sig);
612 }
613
614 /*
615 * Don't set lwp_eosys here. sendsig() is called via psig() after
616 * lwp_eosys is handled, so setting it here would affect the next
617 * system call.
618 */
619 return (1);
620
621 badstack:
622 no_fault();
623 if (watched)
624 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE);
625 if (tuc)
626 kmem_free(tuc, sizeof (*tuc));
627 #ifdef DEBUG
628 printf("sendsig32: bad signal stack cmd=%s pid=%d, sig=%d\n",
629 PTOU(p)->u_comm, p->p_pid, sig);
630 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n",
631 (void *)sp, (void *)hdlr, (uintptr_t)upc);
632 #endif
633 return (0);
634 }
635
636 #endif /* _SYSCALL32_IMPL */
|
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2015 Joyent, Inc.
24 */
25 /*
26 * Copyright 2010 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 /* Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
31 /* Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T */
32 /* All Rights Reserved */
33
34 /*
35 * Copyright 2023 Oxide Computer Company
36 */
37
38 #include <sys/types.h>
39 #include <sys/param.h>
40 #include <sys/sysmacros.h>
41 #include <sys/signal.h>
42 #include <sys/systm.h>
43 #include <sys/user.h>
44 #include <sys/mman.h>
45 #include <sys/class.h>
46 #include <sys/proc.h>
47 #include <sys/procfs.h>
48 #include <sys/buf.h>
49 #include <sys/kmem.h>
50 #include <sys/cred.h>
51 #include <sys/archsystm.h>
52 #include <sys/vmparam.h>
53 #include <sys/prsystm.h>
54 #include <sys/reboot.h>
55 #include <sys/uadmin.h>
56 #include <sys/vfs.h>
57 #include <sys/vnode.h>
99
100 /*
101 * Construct the execution environment for the user's signal
102 * handler and arrange for control to be given to it on return
103 * to userland. The library code now calls setcontext() to
104 * clean up after the signal handler, so sigret() is no longer
105 * needed.
106 *
107 * (The various 'volatile' declarations are need to ensure that values
108 * are correct on the error return from on_fault().)
109 */
110
111
112 /*
113 * An amd64 signal frame looks like this on the stack:
114 *
115 * old %rsp:
116 * <128 bytes of untouched stack space>
117 * <a siginfo_t [optional]>
118 * <a ucontext_t>
119 * <a ucontext_t's xsave state>
120 * <siginfo_t *> ---+
121 * <signal number> | sigframe
122 * new %rsp: <return address (deliberately invalid)> ---+
123 *
124 * The signal number and siginfo_t pointer are only pushed onto the stack in
125 * order to allow stack backtraces. The actual signal handling code expects the
126 * arguments in registers.
127 */
128
129 struct sigframe {
130 caddr_t retaddr;
131 long signo;
132 siginfo_t *sip;
133 };
134
135 int
136 sendsig(int sig, k_siginfo_t *sip, void (*hdlr)())
137 {
138 volatile size_t minstacksz;
139 boolean_t newstack;
140 size_t xsave_size;
141 int ret;
142 label_t ljb;
143 volatile caddr_t sp;
144 caddr_t fp;
145 volatile struct regs *rp;
146 volatile greg_t upc;
147 volatile proc_t *p = ttoproc(curthread);
148 struct as *as = p->p_as;
149 klwp_t *lwp = ttolwp(curthread);
150 ucontext_t *volatile tuc = NULL;
151 ucontext_t *uc;
152 siginfo_t *sip_addr;
153 volatile int watched;
154
155 /*
156 * This routine is utterly dependent upon STACK_ALIGN being
157 * 16 and STACK_ENTRY_ALIGN being 8. Let's just acknowledge
158 * that and require it.
159 */
160
161 #if STACK_ALIGN != 16 || STACK_ENTRY_ALIGN != 8
162 #error "sendsig() amd64 did not find the expected stack alignments"
163 #endif
164
165 rp = lwptoregs(lwp);
166 upc = rp->r_pc;
167
168 /*
169 * Since we're setting up to run the signal handler we have to
170 * arrange that the stack at entry to the handler is (only)
171 * STACK_ENTRY_ALIGN (i.e. 8) byte aligned so that when the handler
172 * executes its push of %rbp, the stack realigns to STACK_ALIGN
173 * (i.e. 16) correctly.
174 *
175 * The new sp will point to the sigframe and the ucontext_t. The
176 * above means that sp (and thus sigframe) will be 8-byte aligned,
177 * but not 16-byte aligned. ucontext_t, however, contains %xmm regs
178 * which must be 16-byte aligned. Because of this, for correct
179 * alignment, sigframe must be a multiple of 8-bytes in length, but
180 * not 16-bytes. This will place ucontext_t at a nice 16-byte boundary.
181 *
182 * When we move onto the xsave state, right now, we don't guarantee any
183 * alignment of the resulting data, but we will ensure that the
184 * resulting sp does have proper alignment. This will ensure that the
185 * guarantee on the ucontex_t is not violated.
186 */
187
188 CTASSERT((sizeof (struct sigframe) % 16) == 8);
189
190 minstacksz = sizeof (struct sigframe) + SA(sizeof (*uc));
191 if (sip != NULL)
192 minstacksz += SA(sizeof (siginfo_t));
193
194 if (fpu_xsave_enabled()) {
195 xsave_size = SA(fpu_signal_size(lwp));
196 minstacksz += xsave_size;
197 } else {
198 xsave_size = 0;
199 }
200
201 ASSERT((minstacksz & (STACK_ENTRY_ALIGN - 1ul)) == 0);
202
203 /*
204 * Figure out whether we will be handling this signal on
205 * an alternate stack specified by the user. Then allocate
206 * and validate the stack requirements for the signal handler
207 * context. on_fault will catch any faults.
208 */
209 newstack = sigismember(&PTOU(curproc)->u_sigonstack, sig) &&
210 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE));
211
212 /*
213 * If this is a branded process, the brand may provide an alternate
214 * stack pointer for signal delivery:
215 */
216 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig_stack != NULL) {
217 /*
218 * Use the stack pointer value provided by the brand,
219 * accounting for the 128-byte reserved region.
220 */
297 curthread->t_rprof->rp_anystate) {
298 /*
299 * We stand on our head to deal with
300 * the real time profiling signal.
301 * Fill in the stuff that doesn't fit
302 * in a normal k_siginfo structure.
303 */
304 int i = sip->si_nsysarg;
305
306 while (--i >= 0)
307 sulword_noerr(
308 (ulong_t *)&(sip_addr->si_sysarg[i]),
309 (ulong_t)lwp->lwp_arg[i]);
310 copyout_noerr(curthread->t_rprof->rp_state,
311 sip_addr->si_mstate,
312 sizeof (curthread->t_rprof->rp_state));
313 }
314 } else
315 sip_addr = NULL;
316
317 no_fault();
318
319 /*
320 * Save the current context on the user stack directly after the
321 * sigframe. Since sigframe is 8-byte-but-not-16-byte aligned, and since
322 * sizeof (struct sigframe) is 24, this guarantees 16-byte alignment for
323 * ucontext_t and its %xmm registers. The xsave state part of the
324 * ucontext_t may be inbetween these two. However, we have ensured that
325 * the size of the stack space is 16-byte aligned as the actual size may
326 * vary.
327 */
328 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP);
329 if (xsave_size != 0) {
330 tuc->uc_xsave = (unsigned long)(sp + sizeof (struct sigframe));
331 }
332 uc = (ucontext_t *)(sp + sizeof (struct sigframe) + xsave_size);
333 ret = savecontext(tuc, &lwp->lwp_sigoldmask, SAVECTXT_F_EXTD |
334 SAVECTXT_F_ONFAULT);
335 if (ret != 0)
336 goto postfault;
337 if (on_fault(&ljb))
338 goto badstack;
339 copyout_noerr(tuc, uc, sizeof (*tuc));
340 kmem_free(tuc, sizeof (*tuc));
341 tuc = NULL;
342
343 DTRACE_PROBE3(oldcontext__set, klwp_t *, lwp,
344 uintptr_t, lwp->lwp_oldcontext, uintptr_t, (uintptr_t)uc);
345 lwp->lwp_oldcontext = (uintptr_t)uc;
346
347 if (newstack) {
348 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK;
349 if (lwp->lwp_ustack)
350 copyout_noerr(&lwp->lwp_sigaltstack,
351 (stack_t *)lwp->lwp_ustack, sizeof (stack_t));
352 }
353
354 /*
355 * Set up signal handler return and stack linkage
356 */
390 rp->r_ss = UDS_SEL;
391 }
392
393 /*
394 * Allow the brand to perform additional book-keeping once the signal
395 * handling frame has been fully assembled:
396 */
397 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig != NULL) {
398 BROP(p)->b_sendsig(sig);
399 }
400
401 /*
402 * Don't set lwp_eosys here. sendsig() is called via psig() after
403 * lwp_eosys is handled, so setting it here would affect the next
404 * system call.
405 */
406 return (1);
407
408 badstack:
409 no_fault();
410 postfault:
411 if (watched)
412 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE);
413 if (tuc)
414 kmem_free(tuc, sizeof (*tuc));
415 #ifdef DEBUG
416 printf("sendsig: bad signal stack cmd=%s, pid=%d, sig=%d\n",
417 PTOU(p)->u_comm, p->p_pid, sig);
418 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n",
419 (void *)sp, (void *)hdlr, (uintptr_t)upc);
420 #endif
421 return (0);
422 }
423
424 #ifdef _SYSCALL32_IMPL
425
426 /*
427 * An i386 SVR4/ABI signal frame looks like this on the stack:
428 *
429 * old %esp:
430 * <a siginfo32_t [optional]>
431 * <a ucontext32_t>
432 * <a ucontext32_t's xsave state>
433 * <pointer to that ucontext32_t>
434 * <pointer to that siginfo32_t>
435 * <signo>
436 * new %esp: <return address (deliberately invalid)>
437 */
438 struct sigframe32 {
439 caddr32_t retaddr;
440 uint32_t signo;
441 caddr32_t sip;
442 caddr32_t ucp;
443 };
444
445 int
446 sendsig32(int sig, k_siginfo_t *sip, void (*hdlr)())
447 {
448 volatile size_t minstacksz;
449 boolean_t newstack;
450 size_t xsave_size;
451 int ret;
452 label_t ljb;
453 volatile caddr_t sp;
454 caddr_t fp;
455 volatile struct regs *rp;
456 volatile greg_t upc;
457 volatile proc_t *p = ttoproc(curthread);
458 klwp_t *lwp = ttolwp(curthread);
459 ucontext32_t *volatile tuc = NULL;
460 ucontext32_t *uc;
461 siginfo32_t *sip_addr;
462 volatile int watched;
463
464 rp = lwptoregs(lwp);
465 upc = rp->r_pc;
466
467 minstacksz = SA32(sizeof (struct sigframe32)) + SA32(sizeof (*uc));
468 if (sip != NULL)
469 minstacksz += SA32(sizeof (siginfo32_t));
470
471 if (fpu_xsave_enabled()) {
472 xsave_size = SA32(fpu_signal_size(lwp));
473 minstacksz += xsave_size;
474 } else {
475 xsave_size = 0;
476 }
477 ASSERT((minstacksz & (STACK_ALIGN32 - 1)) == 0);
478
479 /*
480 * Figure out whether we will be handling this signal on
481 * an alternate stack specified by the user. Then allocate
482 * and validate the stack requirements for the signal handler
483 * context. on_fault will catch any faults.
484 */
485 newstack = sigismember(&PTOU(curproc)->u_sigonstack, sig) &&
486 !(lwp->lwp_sigaltstack.ss_flags & (SS_ONSTACK|SS_DISABLE));
487
488 /*
489 * If this is a branded process, the brand may provide an alternate
490 * stack pointer for signal delivery:
491 */
492 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig_stack != NULL) {
493 /*
494 * Use the stack pointer value provided by the brand:
495 */
496 newstack = 0;
563 if (sig == SIGPROF &&
564 curthread->t_rprof != NULL &&
565 curthread->t_rprof->rp_anystate) {
566 /*
567 * We stand on our head to deal with
568 * the real-time profiling signal.
569 * Fill in the stuff that doesn't fit
570 * in a normal k_siginfo structure.
571 */
572 int i = sip->si_nsysarg;
573
574 while (--i >= 0)
575 suword32_noerr(&(sip_addr->si_sysarg[i]),
576 (uint32_t)lwp->lwp_arg[i]);
577 copyout_noerr(curthread->t_rprof->rp_state,
578 sip_addr->si_mstate,
579 sizeof (curthread->t_rprof->rp_state));
580 }
581 } else
582 sip_addr = NULL;
583 no_fault();
584
585 /* save the current context on the user stack */
586 tuc = kmem_alloc(sizeof (*tuc), KM_SLEEP);
587 fp -= SA32(sizeof (*tuc));
588 uc = (ucontext32_t *)fp;
589 if (xsave_size != 0) {
590 fp -= xsave_size;
591 tuc->uc_xsave = (int32_t)(uintptr_t)fp;
592 }
593 ret = savecontext32(tuc, &lwp->lwp_sigoldmask, SAVECTXT_F_EXTD |
594 SAVECTXT_F_ONFAULT);
595 if (ret != 0)
596 goto postfault;
597 if (on_fault(&ljb))
598 goto badstack;
599 copyout_noerr(tuc, uc, sizeof (*tuc));
600 kmem_free(tuc, sizeof (*tuc));
601 tuc = NULL;
602
603 DTRACE_PROBE3(oldcontext__set, klwp_t *, lwp,
604 uintptr_t, lwp->lwp_oldcontext, uintptr_t, (uintptr_t)uc);
605 lwp->lwp_oldcontext = (uintptr_t)uc;
606
607 if (newstack) {
608 lwp->lwp_sigaltstack.ss_flags |= SS_ONSTACK;
609 if (lwp->lwp_ustack) {
610 stack32_t stk32;
611
612 stk32.ss_sp = (caddr32_t)(uintptr_t)
613 lwp->lwp_sigaltstack.ss_sp;
614 stk32.ss_size = (size32_t)
615 lwp->lwp_sigaltstack.ss_size;
616 stk32.ss_flags = (int32_t)
650 rp->r_ss = UDS_SEL;
651 }
652
653 /*
654 * Allow the brand to perform additional book-keeping once the signal
655 * handling frame has been fully assembled:
656 */
657 if (PROC_IS_BRANDED(p) && BROP(p)->b_sendsig != NULL) {
658 BROP(p)->b_sendsig(sig);
659 }
660
661 /*
662 * Don't set lwp_eosys here. sendsig() is called via psig() after
663 * lwp_eosys is handled, so setting it here would affect the next
664 * system call.
665 */
666 return (1);
667
668 badstack:
669 no_fault();
670 postfault:
671 if (watched)
672 watch_enable_addr((caddr_t)sp, minstacksz, S_WRITE);
673 if (tuc)
674 kmem_free(tuc, sizeof (*tuc));
675 #ifdef DEBUG
676 printf("sendsig32: bad signal stack cmd=%s pid=%d, sig=%d\n",
677 PTOU(p)->u_comm, p->p_pid, sig);
678 printf("on fault, sigsp = 0x%p, action = 0x%p, upc = 0x%lx\n",
679 (void *)sp, (void *)hdlr, (uintptr_t)upc);
680 #endif
681 return (0);
682 }
683
684 #endif /* _SYSCALL32_IMPL */
|