1 /*
2 * linux/arch/alpha/kernel/signal.c
3 *
4 * Copyright (C) 1995 Linus Torvalds
5 *
6 * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson
7 */
8
9 #include <linux/sched.h>
10 #include <linux/kernel.h>
11 #include <linux/signal.h>
12 #include <linux/errno.h>
13 #include <linux/wait.h>
14 #include <linux/ptrace.h>
15 #include <linux/unistd.h>
16 #include <linux/mm.h>
17 #include <linux/smp.h>
18 #include <linux/stddef.h>
19 #include <linux/tty.h>
20 #include <linux/binfmts.h>
21 #include <linux/bitops.h>
22 #include <linux/syscalls.h>
23 #include <linux/tracehook.h>
24
25 #include <asm/uaccess.h>
26 #include <asm/sigcontext.h>
27 #include <asm/ucontext.h>
28
29 #include "proto.h"
30
31
32 #define DEBUG_SIG 0
33
34 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
35
36 asmlinkage void ret_from_sys_call(void);
37 static void do_signal(struct pt_regs *, struct switch_stack *,
38 unsigned long, unsigned long);
39
40
41 /*
42 * The OSF/1 sigprocmask calling sequence is different from the
43 * C sigprocmask() sequence..
44 */
SYSCALL_DEFINE2(osf_sigprocmask,int,how,unsigned long,newmask)45 SYSCALL_DEFINE2(osf_sigprocmask, int, how, unsigned long, newmask)
46 {
47 sigset_t oldmask;
48 sigset_t mask;
49 unsigned long res;
50
51 siginitset(&mask, newmask & _BLOCKABLE);
52 res = sigprocmask(how, &mask, &oldmask);
53 if (!res) {
54 force_successful_syscall_return();
55 res = oldmask.sig[0];
56 }
57 return res;
58 }
59
SYSCALL_DEFINE3(osf_sigaction,int,sig,const struct osf_sigaction __user *,act,struct osf_sigaction __user *,oact)60 SYSCALL_DEFINE3(osf_sigaction, int, sig,
61 const struct osf_sigaction __user *, act,
62 struct osf_sigaction __user *, oact)
63 {
64 struct k_sigaction new_ka, old_ka;
65 int ret;
66
67 if (act) {
68 old_sigset_t mask;
69 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
70 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
71 __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
72 __get_user(mask, &act->sa_mask))
73 return -EFAULT;
74 siginitset(&new_ka.sa.sa_mask, mask);
75 new_ka.ka_restorer = NULL;
76 }
77
78 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
79
80 if (!ret && oact) {
81 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
82 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
83 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
84 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
85 return -EFAULT;
86 }
87
88 return ret;
89 }
90
SYSCALL_DEFINE5(rt_sigaction,int,sig,const struct sigaction __user *,act,struct sigaction __user *,oact,size_t,sigsetsize,void __user *,restorer)91 SYSCALL_DEFINE5(rt_sigaction, int, sig, const struct sigaction __user *, act,
92 struct sigaction __user *, oact,
93 size_t, sigsetsize, void __user *, restorer)
94 {
95 struct k_sigaction new_ka, old_ka;
96 int ret;
97
98 /* XXX: Don't preclude handling different sized sigset_t's. */
99 if (sigsetsize != sizeof(sigset_t))
100 return -EINVAL;
101
102 if (act) {
103 new_ka.ka_restorer = restorer;
104 if (copy_from_user(&new_ka.sa, act, sizeof(*act)))
105 return -EFAULT;
106 }
107
108 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
109
110 if (!ret && oact) {
111 if (copy_to_user(oact, &old_ka.sa, sizeof(*oact)))
112 return -EFAULT;
113 }
114
115 return ret;
116 }
117
118 /*
119 * Atomically swap in the new signal mask, and wait for a signal.
120 */
SYSCALL_DEFINE1(sigsuspend,old_sigset_t,mask)121 SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
122 {
123 mask &= _BLOCKABLE;
124 spin_lock_irq(¤t->sighand->siglock);
125 current->saved_sigmask = current->blocked;
126 siginitset(¤t->blocked, mask);
127 recalc_sigpending();
128 spin_unlock_irq(¤t->sighand->siglock);
129
130 current->state = TASK_INTERRUPTIBLE;
131 schedule();
132 set_thread_flag(TIF_RESTORE_SIGMASK);
133 return -ERESTARTNOHAND;
134 }
135
136 asmlinkage int
sys_sigaltstack(const stack_t __user * uss,stack_t __user * uoss)137 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
138 {
139 return do_sigaltstack(uss, uoss, rdusp());
140 }
141
142 /*
143 * Do a signal return; undo the signal stack.
144 */
145
146 #if _NSIG_WORDS > 1
147 # error "Non SA_SIGINFO frame needs rearranging"
148 #endif
149
150 struct sigframe
151 {
152 struct sigcontext sc;
153 unsigned int retcode[3];
154 };
155
156 struct rt_sigframe
157 {
158 struct siginfo info;
159 struct ucontext uc;
160 unsigned int retcode[3];
161 };
162
163 /* If this changes, userland unwinders that Know Things about our signal
164 frame will break. Do not undertake lightly. It also implies an ABI
165 change wrt the size of siginfo_t, which may cause some pain. */
166 extern char compile_time_assert
167 [offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1];
168
169 #define INSN_MOV_R30_R16 0x47fe0410
170 #define INSN_LDI_R0 0x201f0000
171 #define INSN_CALLSYS 0x00000083
172
173 static long
restore_sigcontext(struct sigcontext __user * sc,struct pt_regs * regs,struct switch_stack * sw)174 restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
175 struct switch_stack *sw)
176 {
177 unsigned long usp;
178 long i, err = __get_user(regs->pc, &sc->sc_pc);
179
180 current_thread_info()->restart_block.fn = do_no_restart_syscall;
181
182 sw->r26 = (unsigned long) ret_from_sys_call;
183
184 err |= __get_user(regs->r0, sc->sc_regs+0);
185 err |= __get_user(regs->r1, sc->sc_regs+1);
186 err |= __get_user(regs->r2, sc->sc_regs+2);
187 err |= __get_user(regs->r3, sc->sc_regs+3);
188 err |= __get_user(regs->r4, sc->sc_regs+4);
189 err |= __get_user(regs->r5, sc->sc_regs+5);
190 err |= __get_user(regs->r6, sc->sc_regs+6);
191 err |= __get_user(regs->r7, sc->sc_regs+7);
192 err |= __get_user(regs->r8, sc->sc_regs+8);
193 err |= __get_user(sw->r9, sc->sc_regs+9);
194 err |= __get_user(sw->r10, sc->sc_regs+10);
195 err |= __get_user(sw->r11, sc->sc_regs+11);
196 err |= __get_user(sw->r12, sc->sc_regs+12);
197 err |= __get_user(sw->r13, sc->sc_regs+13);
198 err |= __get_user(sw->r14, sc->sc_regs+14);
199 err |= __get_user(sw->r15, sc->sc_regs+15);
200 err |= __get_user(regs->r16, sc->sc_regs+16);
201 err |= __get_user(regs->r17, sc->sc_regs+17);
202 err |= __get_user(regs->r18, sc->sc_regs+18);
203 err |= __get_user(regs->r19, sc->sc_regs+19);
204 err |= __get_user(regs->r20, sc->sc_regs+20);
205 err |= __get_user(regs->r21, sc->sc_regs+21);
206 err |= __get_user(regs->r22, sc->sc_regs+22);
207 err |= __get_user(regs->r23, sc->sc_regs+23);
208 err |= __get_user(regs->r24, sc->sc_regs+24);
209 err |= __get_user(regs->r25, sc->sc_regs+25);
210 err |= __get_user(regs->r26, sc->sc_regs+26);
211 err |= __get_user(regs->r27, sc->sc_regs+27);
212 err |= __get_user(regs->r28, sc->sc_regs+28);
213 err |= __get_user(regs->gp, sc->sc_regs+29);
214 err |= __get_user(usp, sc->sc_regs+30);
215 wrusp(usp);
216
217 for (i = 0; i < 31; i++)
218 err |= __get_user(sw->fp[i], sc->sc_fpregs+i);
219 err |= __get_user(sw->fp[31], &sc->sc_fpcr);
220
221 return err;
222 }
223
224 /* Note that this syscall is also used by setcontext(3) to install
225 a given sigcontext. This because it's impossible to set *all*
226 registers and transfer control from userland. */
227
228 asmlinkage void
do_sigreturn(struct sigcontext __user * sc,struct pt_regs * regs,struct switch_stack * sw)229 do_sigreturn(struct sigcontext __user *sc, struct pt_regs *regs,
230 struct switch_stack *sw)
231 {
232 sigset_t set;
233
234 /* Verify that it's a good sigcontext before using it */
235 if (!access_ok(VERIFY_READ, sc, sizeof(*sc)))
236 goto give_sigsegv;
237 if (__get_user(set.sig[0], &sc->sc_mask))
238 goto give_sigsegv;
239
240 sigdelsetmask(&set, ~_BLOCKABLE);
241 spin_lock_irq(¤t->sighand->siglock);
242 current->blocked = set;
243 recalc_sigpending();
244 spin_unlock_irq(¤t->sighand->siglock);
245
246 if (restore_sigcontext(sc, regs, sw))
247 goto give_sigsegv;
248
249 /* Send SIGTRAP if we're single-stepping: */
250 if (ptrace_cancel_bpt (current)) {
251 siginfo_t info;
252
253 info.si_signo = SIGTRAP;
254 info.si_errno = 0;
255 info.si_code = TRAP_BRKPT;
256 info.si_addr = (void __user *) regs->pc;
257 info.si_trapno = 0;
258 send_sig_info(SIGTRAP, &info, current);
259 }
260 return;
261
262 give_sigsegv:
263 force_sig(SIGSEGV, current);
264 }
265
266 asmlinkage void
do_rt_sigreturn(struct rt_sigframe __user * frame,struct pt_regs * regs,struct switch_stack * sw)267 do_rt_sigreturn(struct rt_sigframe __user *frame, struct pt_regs *regs,
268 struct switch_stack *sw)
269 {
270 sigset_t set;
271
272 /* Verify that it's a good ucontext_t before using it */
273 if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc)))
274 goto give_sigsegv;
275 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
276 goto give_sigsegv;
277
278 sigdelsetmask(&set, ~_BLOCKABLE);
279 spin_lock_irq(¤t->sighand->siglock);
280 current->blocked = set;
281 recalc_sigpending();
282 spin_unlock_irq(¤t->sighand->siglock);
283
284 if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw))
285 goto give_sigsegv;
286
287 /* Send SIGTRAP if we're single-stepping: */
288 if (ptrace_cancel_bpt (current)) {
289 siginfo_t info;
290
291 info.si_signo = SIGTRAP;
292 info.si_errno = 0;
293 info.si_code = TRAP_BRKPT;
294 info.si_addr = (void __user *) regs->pc;
295 info.si_trapno = 0;
296 send_sig_info(SIGTRAP, &info, current);
297 }
298 return;
299
300 give_sigsegv:
301 force_sig(SIGSEGV, current);
302 }
303
304
305 /*
306 * Set up a signal frame.
307 */
308
309 static inline void __user *
get_sigframe(struct k_sigaction * ka,unsigned long sp,size_t frame_size)310 get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
311 {
312 if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp))
313 sp = current->sas_ss_sp + current->sas_ss_size;
314
315 return (void __user *)((sp - frame_size) & -32ul);
316 }
317
318 static long
setup_sigcontext(struct sigcontext __user * sc,struct pt_regs * regs,struct switch_stack * sw,unsigned long mask,unsigned long sp)319 setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
320 struct switch_stack *sw, unsigned long mask, unsigned long sp)
321 {
322 long i, err = 0;
323
324 err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack);
325 err |= __put_user(mask, &sc->sc_mask);
326 err |= __put_user(regs->pc, &sc->sc_pc);
327 err |= __put_user(8, &sc->sc_ps);
328
329 err |= __put_user(regs->r0 , sc->sc_regs+0);
330 err |= __put_user(regs->r1 , sc->sc_regs+1);
331 err |= __put_user(regs->r2 , sc->sc_regs+2);
332 err |= __put_user(regs->r3 , sc->sc_regs+3);
333 err |= __put_user(regs->r4 , sc->sc_regs+4);
334 err |= __put_user(regs->r5 , sc->sc_regs+5);
335 err |= __put_user(regs->r6 , sc->sc_regs+6);
336 err |= __put_user(regs->r7 , sc->sc_regs+7);
337 err |= __put_user(regs->r8 , sc->sc_regs+8);
338 err |= __put_user(sw->r9 , sc->sc_regs+9);
339 err |= __put_user(sw->r10 , sc->sc_regs+10);
340 err |= __put_user(sw->r11 , sc->sc_regs+11);
341 err |= __put_user(sw->r12 , sc->sc_regs+12);
342 err |= __put_user(sw->r13 , sc->sc_regs+13);
343 err |= __put_user(sw->r14 , sc->sc_regs+14);
344 err |= __put_user(sw->r15 , sc->sc_regs+15);
345 err |= __put_user(regs->r16, sc->sc_regs+16);
346 err |= __put_user(regs->r17, sc->sc_regs+17);
347 err |= __put_user(regs->r18, sc->sc_regs+18);
348 err |= __put_user(regs->r19, sc->sc_regs+19);
349 err |= __put_user(regs->r20, sc->sc_regs+20);
350 err |= __put_user(regs->r21, sc->sc_regs+21);
351 err |= __put_user(regs->r22, sc->sc_regs+22);
352 err |= __put_user(regs->r23, sc->sc_regs+23);
353 err |= __put_user(regs->r24, sc->sc_regs+24);
354 err |= __put_user(regs->r25, sc->sc_regs+25);
355 err |= __put_user(regs->r26, sc->sc_regs+26);
356 err |= __put_user(regs->r27, sc->sc_regs+27);
357 err |= __put_user(regs->r28, sc->sc_regs+28);
358 err |= __put_user(regs->gp , sc->sc_regs+29);
359 err |= __put_user(sp, sc->sc_regs+30);
360 err |= __put_user(0, sc->sc_regs+31);
361
362 for (i = 0; i < 31; i++)
363 err |= __put_user(sw->fp[i], sc->sc_fpregs+i);
364 err |= __put_user(0, sc->sc_fpregs+31);
365 err |= __put_user(sw->fp[31], &sc->sc_fpcr);
366
367 err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0);
368 err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1);
369 err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2);
370
371 return err;
372 }
373
374 static int
setup_frame(int sig,struct k_sigaction * ka,sigset_t * set,struct pt_regs * regs,struct switch_stack * sw)375 setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
376 struct pt_regs *regs, struct switch_stack * sw)
377 {
378 unsigned long oldsp, r26, err = 0;
379 struct sigframe __user *frame;
380
381 oldsp = rdusp();
382 frame = get_sigframe(ka, oldsp, sizeof(*frame));
383 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
384 goto give_sigsegv;
385
386 err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp);
387 if (err)
388 goto give_sigsegv;
389
390 /* Set up to return from userspace. If provided, use a stub
391 already in userspace. */
392 if (ka->ka_restorer) {
393 r26 = (unsigned long) ka->ka_restorer;
394 } else {
395 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
396 err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1);
397 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
398 imb();
399 r26 = (unsigned long) frame->retcode;
400 }
401
402 /* Check that everything was written properly. */
403 if (err)
404 goto give_sigsegv;
405
406 /* "Return" to the handler */
407 regs->r26 = r26;
408 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
409 regs->r16 = sig; /* a0: signal number */
410 regs->r17 = 0; /* a1: exception code */
411 regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */
412 wrusp((unsigned long) frame);
413
414 #if DEBUG_SIG
415 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
416 current->comm, current->pid, frame, regs->pc, regs->r26);
417 #endif
418
419 return 0;
420
421 give_sigsegv:
422 force_sigsegv(sig, current);
423 return -EFAULT;
424 }
425
426 static int
setup_rt_frame(int sig,struct k_sigaction * ka,siginfo_t * info,sigset_t * set,struct pt_regs * regs,struct switch_stack * sw)427 setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
428 sigset_t *set, struct pt_regs *regs, struct switch_stack * sw)
429 {
430 unsigned long oldsp, r26, err = 0;
431 struct rt_sigframe __user *frame;
432
433 oldsp = rdusp();
434 frame = get_sigframe(ka, oldsp, sizeof(*frame));
435 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
436 goto give_sigsegv;
437
438 err |= copy_siginfo_to_user(&frame->info, info);
439
440 /* Create the ucontext. */
441 err |= __put_user(0, &frame->uc.uc_flags);
442 err |= __put_user(0, &frame->uc.uc_link);
443 err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask);
444 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
445 err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags);
446 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
447 err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw,
448 set->sig[0], oldsp);
449 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
450 if (err)
451 goto give_sigsegv;
452
453 /* Set up to return from userspace. If provided, use a stub
454 already in userspace. */
455 if (ka->ka_restorer) {
456 r26 = (unsigned long) ka->ka_restorer;
457 } else {
458 err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0);
459 err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn,
460 frame->retcode+1);
461 err |= __put_user(INSN_CALLSYS, frame->retcode+2);
462 imb();
463 r26 = (unsigned long) frame->retcode;
464 }
465
466 if (err)
467 goto give_sigsegv;
468
469 /* "Return" to the handler */
470 regs->r26 = r26;
471 regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler;
472 regs->r16 = sig; /* a0: signal number */
473 regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */
474 regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */
475 wrusp((unsigned long) frame);
476
477 #if DEBUG_SIG
478 printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n",
479 current->comm, current->pid, frame, regs->pc, regs->r26);
480 #endif
481
482 return 0;
483
484 give_sigsegv:
485 force_sigsegv(sig, current);
486 return -EFAULT;
487 }
488
489
490 /*
491 * OK, we're invoking a handler.
492 */
493 static inline int
handle_signal(int sig,struct k_sigaction * ka,siginfo_t * info,sigset_t * oldset,struct pt_regs * regs,struct switch_stack * sw)494 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
495 sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw)
496 {
497 int ret;
498
499 if (ka->sa.sa_flags & SA_SIGINFO)
500 ret = setup_rt_frame(sig, ka, info, oldset, regs, sw);
501 else
502 ret = setup_frame(sig, ka, oldset, regs, sw);
503
504 if (ret == 0) {
505 spin_lock_irq(¤t->sighand->siglock);
506 sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask);
507 if (!(ka->sa.sa_flags & SA_NODEFER))
508 sigaddset(¤t->blocked,sig);
509 recalc_sigpending();
510 spin_unlock_irq(¤t->sighand->siglock);
511 }
512
513 return ret;
514 }
515
516 static inline void
syscall_restart(unsigned long r0,unsigned long r19,struct pt_regs * regs,struct k_sigaction * ka)517 syscall_restart(unsigned long r0, unsigned long r19,
518 struct pt_regs *regs, struct k_sigaction *ka)
519 {
520 switch (regs->r0) {
521 case ERESTARTSYS:
522 if (!(ka->sa.sa_flags & SA_RESTART)) {
523 case ERESTARTNOHAND:
524 regs->r0 = EINTR;
525 break;
526 }
527 /* fallthrough */
528 case ERESTARTNOINTR:
529 regs->r0 = r0; /* reset v0 and a3 and replay syscall */
530 regs->r19 = r19;
531 regs->pc -= 4;
532 break;
533 case ERESTART_RESTARTBLOCK:
534 regs->r0 = EINTR;
535 break;
536 }
537 }
538
539
540 /*
541 * Note that 'init' is a special process: it doesn't get signals it doesn't
542 * want to handle. Thus you cannot kill init even with a SIGKILL even by
543 * mistake.
544 *
545 * Note that we go through the signals twice: once to check the signals that
546 * the kernel can handle, and then we build all the user-level signal handling
547 * stack-frames in one go after that.
548 *
549 * "r0" and "r19" are the registers we need to restore for system call
550 * restart. "r0" is also used as an indicator whether we can restart at
551 * all (if we get here from anything but a syscall return, it will be 0)
552 */
553 static void
do_signal(struct pt_regs * regs,struct switch_stack * sw,unsigned long r0,unsigned long r19)554 do_signal(struct pt_regs * regs, struct switch_stack * sw,
555 unsigned long r0, unsigned long r19)
556 {
557 siginfo_t info;
558 int signr;
559 unsigned long single_stepping = ptrace_cancel_bpt(current);
560 struct k_sigaction ka;
561 sigset_t *oldset;
562
563 if (test_thread_flag(TIF_RESTORE_SIGMASK))
564 oldset = ¤t->saved_sigmask;
565 else
566 oldset = ¤t->blocked;
567
568 /* This lets the debugger run, ... */
569 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
570
571 /* ... so re-check the single stepping. */
572 single_stepping |= ptrace_cancel_bpt(current);
573
574 if (signr > 0) {
575 /* Whee! Actually deliver the signal. */
576 if (r0)
577 syscall_restart(r0, r19, regs, &ka);
578 if (handle_signal(signr, &ka, &info, oldset, regs, sw) == 0) {
579 /* A signal was successfully delivered, and the
580 saved sigmask was stored on the signal frame,
581 and will be restored by sigreturn. So we can
582 simply clear the restore sigmask flag. */
583 if (test_thread_flag(TIF_RESTORE_SIGMASK))
584 clear_thread_flag(TIF_RESTORE_SIGMASK);
585 }
586 if (single_stepping)
587 ptrace_set_bpt(current); /* re-set bpt */
588 return;
589 }
590
591 if (r0) {
592 switch (regs->r0) {
593 case ERESTARTNOHAND:
594 case ERESTARTSYS:
595 case ERESTARTNOINTR:
596 /* Reset v0 and a3 and replay syscall. */
597 regs->r0 = r0;
598 regs->r19 = r19;
599 regs->pc -= 4;
600 break;
601 case ERESTART_RESTARTBLOCK:
602 /* Force v0 to the restart syscall and reply. */
603 regs->r0 = __NR_restart_syscall;
604 regs->pc -= 4;
605 break;
606 }
607 }
608
609 /* If there's no signal to deliver, we just restore the saved mask. */
610 if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
611 clear_thread_flag(TIF_RESTORE_SIGMASK);
612 sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL);
613 }
614
615 if (single_stepping)
616 ptrace_set_bpt(current); /* re-set breakpoint */
617 }
618
619 void
do_notify_resume(struct pt_regs * regs,struct switch_stack * sw,unsigned long thread_info_flags,unsigned long r0,unsigned long r19)620 do_notify_resume(struct pt_regs *regs, struct switch_stack *sw,
621 unsigned long thread_info_flags,
622 unsigned long r0, unsigned long r19)
623 {
624 if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
625 do_signal(regs, sw, r0, r19);
626
627 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
628 clear_thread_flag(TIF_NOTIFY_RESUME);
629 tracehook_notify_resume(regs);
630 if (current->replacement_session_keyring)
631 key_replace_session_keyring();
632 }
633 }
634