Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/sh/kernel/signal.c | |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
5 | * | |
6 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
7 | * | |
8 | * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima | |
9 | * | |
10 | */ | |
11 | ||
12 | #include <linux/sched.h> | |
13 | #include <linux/mm.h> | |
14 | #include <linux/smp.h> | |
15 | #include <linux/smp_lock.h> | |
16 | #include <linux/kernel.h> | |
17 | #include <linux/signal.h> | |
18 | #include <linux/errno.h> | |
19 | #include <linux/wait.h> | |
20 | #include <linux/ptrace.h> | |
21 | #include <linux/unistd.h> | |
22 | #include <linux/stddef.h> | |
23 | #include <linux/tty.h> | |
24 | #include <linux/personality.h> | |
25 | #include <linux/binfmts.h> | |
26 | ||
27 | #include <asm/ucontext.h> | |
28 | #include <asm/uaccess.h> | |
29 | #include <asm/pgtable.h> | |
30 | #include <asm/cacheflush.h> | |
31 | ||
32 | #define DEBUG_SIG 0 | |
33 | ||
34 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
35 | ||
36 | asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset); | |
37 | ||
38 | /* | |
39 | * Atomically swap in the new signal mask, and wait for a signal. | |
40 | */ | |
41 | asmlinkage int | |
42 | sys_sigsuspend(old_sigset_t mask, | |
43 | unsigned long r5, unsigned long r6, unsigned long r7, | |
44 | struct pt_regs regs) | |
45 | { | |
46 | sigset_t saveset; | |
47 | ||
48 | mask &= _BLOCKABLE; | |
49 | spin_lock_irq(¤t->sighand->siglock); | |
50 | saveset = current->blocked; | |
51 | siginitset(¤t->blocked, mask); | |
52 | recalc_sigpending(); | |
53 | spin_unlock_irq(¤t->sighand->siglock); | |
54 | ||
55 | regs.regs[0] = -EINTR; | |
56 | while (1) { | |
57 | current->state = TASK_INTERRUPTIBLE; | |
58 | schedule(); | |
59 | if (do_signal(®s, &saveset)) | |
60 | return -EINTR; | |
61 | } | |
62 | } | |
63 | ||
64 | asmlinkage int | |
65 | sys_rt_sigsuspend(sigset_t *unewset, size_t sigsetsize, | |
66 | unsigned long r6, unsigned long r7, | |
67 | struct pt_regs regs) | |
68 | { | |
69 | sigset_t saveset, newset; | |
70 | ||
71 | /* XXX: Don't preclude handling different sized sigset_t's. */ | |
72 | if (sigsetsize != sizeof(sigset_t)) | |
73 | return -EINVAL; | |
74 | ||
75 | if (copy_from_user(&newset, unewset, sizeof(newset))) | |
76 | return -EFAULT; | |
77 | sigdelsetmask(&newset, ~_BLOCKABLE); | |
78 | spin_lock_irq(¤t->sighand->siglock); | |
79 | saveset = current->blocked; | |
80 | current->blocked = newset; | |
81 | recalc_sigpending(); | |
82 | spin_unlock_irq(¤t->sighand->siglock); | |
83 | ||
84 | regs.regs[0] = -EINTR; | |
85 | while (1) { | |
86 | current->state = TASK_INTERRUPTIBLE; | |
87 | schedule(); | |
88 | if (do_signal(®s, &saveset)) | |
89 | return -EINTR; | |
90 | } | |
91 | } | |
92 | ||
93 | asmlinkage int | |
94 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
95 | struct old_sigaction __user *oact) | |
96 | { | |
97 | struct k_sigaction new_ka, old_ka; | |
98 | int ret; | |
99 | ||
100 | if (act) { | |
101 | old_sigset_t mask; | |
102 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
103 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
104 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
105 | return -EFAULT; | |
106 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
107 | __get_user(mask, &act->sa_mask); | |
108 | siginitset(&new_ka.sa.sa_mask, mask); | |
109 | } | |
110 | ||
111 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
112 | ||
113 | if (!ret && oact) { | |
114 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
115 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
116 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
117 | return -EFAULT; | |
118 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
119 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
120 | } | |
121 | ||
122 | return ret; | |
123 | } | |
124 | ||
125 | asmlinkage int | |
126 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss, | |
127 | unsigned long r6, unsigned long r7, | |
128 | struct pt_regs regs) | |
129 | { | |
130 | return do_sigaltstack(uss, uoss, regs.regs[15]); | |
131 | } | |
132 | ||
133 | ||
134 | /* | |
135 | * Do a signal return; undo the signal stack. | |
136 | */ | |
137 | ||
138 | #define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */ | |
139 | #define TRAP16 0xc310 /* Syscall w/no args (NR in R3) */ | |
140 | #define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */ | |
141 | ||
142 | struct sigframe | |
143 | { | |
144 | struct sigcontext sc; | |
145 | unsigned long extramask[_NSIG_WORDS-1]; | |
146 | u16 retcode[8]; | |
147 | }; | |
148 | ||
149 | struct rt_sigframe | |
150 | { | |
151 | struct siginfo info; | |
152 | struct ucontext uc; | |
153 | u16 retcode[8]; | |
154 | }; | |
155 | ||
156 | #ifdef CONFIG_SH_FPU | |
157 | static inline int restore_sigcontext_fpu(struct sigcontext __user *sc) | |
158 | { | |
159 | struct task_struct *tsk = current; | |
160 | ||
161 | if (!(cpu_data->flags & CPU_HAS_FPU)) | |
162 | return 0; | |
163 | ||
164 | set_used_math(); | |
165 | return __copy_from_user(&tsk->thread.fpu.hard, &sc->sc_fpregs[0], | |
166 | sizeof(long)*(16*2+2)); | |
167 | } | |
168 | ||
169 | static inline int save_sigcontext_fpu(struct sigcontext __user *sc, | |
170 | struct pt_regs *regs) | |
171 | { | |
172 | struct task_struct *tsk = current; | |
173 | ||
174 | if (!(cpu_data->flags & CPU_HAS_FPU)) | |
175 | return 0; | |
176 | ||
177 | if (!used_math()) { | |
178 | __put_user(0, &sc->sc_ownedfp); | |
179 | return 0; | |
180 | } | |
181 | ||
182 | __put_user(1, &sc->sc_ownedfp); | |
183 | ||
184 | /* This will cause a "finit" to be triggered by the next | |
185 | attempted FPU operation by the 'current' process. | |
186 | */ | |
187 | clear_used_math(); | |
188 | ||
189 | unlazy_fpu(tsk, regs); | |
190 | return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.fpu.hard, | |
191 | sizeof(long)*(16*2+2)); | |
192 | } | |
193 | #endif /* CONFIG_SH_FPU */ | |
194 | ||
195 | static int | |
196 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p) | |
197 | { | |
198 | unsigned int err = 0; | |
199 | ||
200 | #define COPY(x) err |= __get_user(regs->x, &sc->sc_##x) | |
201 | COPY(regs[1]); | |
202 | COPY(regs[2]); COPY(regs[3]); | |
203 | COPY(regs[4]); COPY(regs[5]); | |
204 | COPY(regs[6]); COPY(regs[7]); | |
205 | COPY(regs[8]); COPY(regs[9]); | |
206 | COPY(regs[10]); COPY(regs[11]); | |
207 | COPY(regs[12]); COPY(regs[13]); | |
208 | COPY(regs[14]); COPY(regs[15]); | |
209 | COPY(gbr); COPY(mach); | |
210 | COPY(macl); COPY(pr); | |
211 | COPY(sr); COPY(pc); | |
212 | #undef COPY | |
213 | ||
214 | #ifdef CONFIG_SH_FPU | |
215 | if (cpu_data->flags & CPU_HAS_FPU) { | |
216 | int owned_fp; | |
217 | struct task_struct *tsk = current; | |
218 | ||
219 | regs->sr |= SR_FD; /* Release FPU */ | |
220 | clear_fpu(tsk, regs); | |
221 | clear_used_math(); | |
222 | __get_user (owned_fp, &sc->sc_ownedfp); | |
223 | if (owned_fp) | |
224 | err |= restore_sigcontext_fpu(sc); | |
225 | } | |
226 | #endif | |
227 | ||
228 | regs->tra = -1; /* disable syscall checks */ | |
229 | err |= __get_user(*r0_p, &sc->sc_regs[0]); | |
230 | return err; | |
231 | } | |
232 | ||
233 | asmlinkage int sys_sigreturn(unsigned long r4, unsigned long r5, | |
234 | unsigned long r6, unsigned long r7, | |
235 | struct pt_regs regs) | |
236 | { | |
237 | struct sigframe __user *frame = (struct sigframe __user *)regs.regs[15]; | |
238 | sigset_t set; | |
239 | int r0; | |
240 | ||
241 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
242 | goto badframe; | |
243 | ||
244 | if (__get_user(set.sig[0], &frame->sc.oldmask) | |
245 | || (_NSIG_WORDS > 1 | |
246 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
247 | sizeof(frame->extramask)))) | |
248 | goto badframe; | |
249 | ||
250 | sigdelsetmask(&set, ~_BLOCKABLE); | |
251 | ||
252 | spin_lock_irq(¤t->sighand->siglock); | |
253 | current->blocked = set; | |
254 | recalc_sigpending(); | |
255 | spin_unlock_irq(¤t->sighand->siglock); | |
256 | ||
257 | if (restore_sigcontext(®s, &frame->sc, &r0)) | |
258 | goto badframe; | |
259 | return r0; | |
260 | ||
261 | badframe: | |
262 | force_sig(SIGSEGV, current); | |
263 | return 0; | |
264 | } | |
265 | ||
266 | asmlinkage int sys_rt_sigreturn(unsigned long r4, unsigned long r5, | |
267 | unsigned long r6, unsigned long r7, | |
268 | struct pt_regs regs) | |
269 | { | |
270 | struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs.regs[15]; | |
271 | sigset_t set; | |
272 | stack_t st; | |
273 | int r0; | |
274 | ||
275 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
276 | goto badframe; | |
277 | ||
278 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
279 | goto badframe; | |
280 | ||
281 | sigdelsetmask(&set, ~_BLOCKABLE); | |
282 | spin_lock_irq(¤t->sighand->siglock); | |
283 | current->blocked = set; | |
284 | recalc_sigpending(); | |
285 | spin_unlock_irq(¤t->sighand->siglock); | |
286 | ||
287 | if (restore_sigcontext(®s, &frame->uc.uc_mcontext, &r0)) | |
288 | goto badframe; | |
289 | ||
290 | if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st))) | |
291 | goto badframe; | |
292 | /* It is more difficult to avoid calling this function than to | |
293 | call it and ignore errors. */ | |
294 | do_sigaltstack(&st, NULL, regs.regs[15]); | |
295 | ||
296 | return r0; | |
297 | ||
298 | badframe: | |
299 | force_sig(SIGSEGV, current); | |
300 | return 0; | |
301 | } | |
302 | ||
303 | /* | |
304 | * Set up a signal frame. | |
305 | */ | |
306 | ||
307 | static int | |
308 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, | |
309 | unsigned long mask) | |
310 | { | |
311 | int err = 0; | |
312 | ||
313 | #define COPY(x) err |= __put_user(regs->x, &sc->sc_##x) | |
314 | COPY(regs[0]); COPY(regs[1]); | |
315 | COPY(regs[2]); COPY(regs[3]); | |
316 | COPY(regs[4]); COPY(regs[5]); | |
317 | COPY(regs[6]); COPY(regs[7]); | |
318 | COPY(regs[8]); COPY(regs[9]); | |
319 | COPY(regs[10]); COPY(regs[11]); | |
320 | COPY(regs[12]); COPY(regs[13]); | |
321 | COPY(regs[14]); COPY(regs[15]); | |
322 | COPY(gbr); COPY(mach); | |
323 | COPY(macl); COPY(pr); | |
324 | COPY(sr); COPY(pc); | |
325 | #undef COPY | |
326 | ||
327 | #ifdef CONFIG_SH_FPU | |
328 | err |= save_sigcontext_fpu(sc, regs); | |
329 | #endif | |
330 | ||
331 | /* non-iBCS2 extensions.. */ | |
332 | err |= __put_user(mask, &sc->oldmask); | |
333 | ||
334 | return err; | |
335 | } | |
336 | ||
337 | /* | |
338 | * Determine which stack to use.. | |
339 | */ | |
340 | static inline void __user * | |
341 | get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) | |
342 | { | |
343 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
344 | if (sas_ss_flags(sp) == 0) | |
345 | sp = current->sas_ss_sp + current->sas_ss_size; | |
346 | } | |
347 | ||
348 | return (void __user *)((sp - frame_size) & -8ul); | |
349 | } | |
350 | ||
351 | static void setup_frame(int sig, struct k_sigaction *ka, | |
352 | sigset_t *set, struct pt_regs *regs) | |
353 | { | |
354 | struct sigframe __user *frame; | |
355 | int err = 0; | |
356 | int signal; | |
357 | ||
358 | frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); | |
359 | ||
360 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
361 | goto give_sigsegv; | |
362 | ||
363 | signal = current_thread_info()->exec_domain | |
364 | && current_thread_info()->exec_domain->signal_invmap | |
365 | && sig < 32 | |
366 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
367 | : sig; | |
368 | ||
369 | err |= setup_sigcontext(&frame->sc, regs, set->sig[0]); | |
370 | ||
371 | if (_NSIG_WORDS > 1) { | |
372 | err |= __copy_to_user(frame->extramask, &set->sig[1], | |
373 | sizeof(frame->extramask)); | |
374 | } | |
375 | ||
376 | /* Set up to return from userspace. If provided, use a stub | |
377 | already in userspace. */ | |
378 | if (ka->sa.sa_flags & SA_RESTORER) { | |
379 | regs->pr = (unsigned long) ka->sa.sa_restorer; | |
380 | } else { | |
381 | /* Generate return code (system call to sigreturn) */ | |
382 | err |= __put_user(MOVW(7), &frame->retcode[0]); | |
383 | err |= __put_user(TRAP16, &frame->retcode[1]); | |
384 | err |= __put_user(OR_R0_R0, &frame->retcode[2]); | |
385 | err |= __put_user(OR_R0_R0, &frame->retcode[3]); | |
386 | err |= __put_user(OR_R0_R0, &frame->retcode[4]); | |
387 | err |= __put_user(OR_R0_R0, &frame->retcode[5]); | |
388 | err |= __put_user(OR_R0_R0, &frame->retcode[6]); | |
389 | err |= __put_user((__NR_sigreturn), &frame->retcode[7]); | |
390 | regs->pr = (unsigned long) frame->retcode; | |
391 | } | |
392 | ||
393 | if (err) | |
394 | goto give_sigsegv; | |
395 | ||
396 | /* Set up registers for signal handler */ | |
397 | regs->regs[15] = (unsigned long) frame; | |
398 | regs->regs[4] = signal; /* Arg for signal handler */ | |
399 | regs->regs[5] = 0; | |
400 | regs->regs[6] = (unsigned long) &frame->sc; | |
401 | regs->pc = (unsigned long) ka->sa.sa_handler; | |
402 | ||
403 | set_fs(USER_DS); | |
404 | ||
405 | #if DEBUG_SIG | |
406 | printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", | |
407 | current->comm, current->pid, frame, regs->pc, regs->pr); | |
408 | #endif | |
409 | ||
410 | flush_cache_sigtramp(regs->pr); | |
411 | if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) | |
412 | flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); | |
413 | return; | |
414 | ||
415 | give_sigsegv: | |
416 | force_sigsegv(sig, current); | |
417 | } | |
418 | ||
419 | static void setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
420 | sigset_t *set, struct pt_regs *regs) | |
421 | { | |
422 | struct rt_sigframe __user *frame; | |
423 | int err = 0; | |
424 | int signal; | |
425 | ||
426 | frame = get_sigframe(ka, regs->regs[15], sizeof(*frame)); | |
427 | ||
428 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
429 | goto give_sigsegv; | |
430 | ||
431 | signal = current_thread_info()->exec_domain | |
432 | && current_thread_info()->exec_domain->signal_invmap | |
433 | && sig < 32 | |
434 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
435 | : sig; | |
436 | ||
437 | err |= copy_siginfo_to_user(&frame->info, info); | |
438 | ||
439 | /* Create the ucontext. */ | |
440 | err |= __put_user(0, &frame->uc.uc_flags); | |
441 | err |= __put_user(0, &frame->uc.uc_link); | |
442 | err |= __put_user((void *)current->sas_ss_sp, | |
443 | &frame->uc.uc_stack.ss_sp); | |
444 | err |= __put_user(sas_ss_flags(regs->regs[15]), | |
445 | &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, | |
448 | regs, set->sig[0]); | |
449 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
450 | ||
451 | /* Set up to return from userspace. If provided, use a stub | |
452 | already in userspace. */ | |
453 | if (ka->sa.sa_flags & SA_RESTORER) { | |
454 | regs->pr = (unsigned long) ka->sa.sa_restorer; | |
455 | } else { | |
456 | /* Generate return code (system call to rt_sigreturn) */ | |
457 | err |= __put_user(MOVW(7), &frame->retcode[0]); | |
458 | err |= __put_user(TRAP16, &frame->retcode[1]); | |
459 | err |= __put_user(OR_R0_R0, &frame->retcode[2]); | |
460 | err |= __put_user(OR_R0_R0, &frame->retcode[3]); | |
461 | err |= __put_user(OR_R0_R0, &frame->retcode[4]); | |
462 | err |= __put_user(OR_R0_R0, &frame->retcode[5]); | |
463 | err |= __put_user(OR_R0_R0, &frame->retcode[6]); | |
464 | err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]); | |
465 | regs->pr = (unsigned long) frame->retcode; | |
466 | } | |
467 | ||
468 | if (err) | |
469 | goto give_sigsegv; | |
470 | ||
471 | /* Set up registers for signal handler */ | |
472 | regs->regs[15] = (unsigned long) frame; | |
473 | regs->regs[4] = signal; /* Arg for signal handler */ | |
474 | regs->regs[5] = (unsigned long) &frame->info; | |
475 | regs->regs[6] = (unsigned long) &frame->uc; | |
476 | regs->pc = (unsigned long) ka->sa.sa_handler; | |
477 | ||
478 | set_fs(USER_DS); | |
479 | ||
480 | #if DEBUG_SIG | |
481 | printk("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n", | |
482 | current->comm, current->pid, frame, regs->pc, regs->pr); | |
483 | #endif | |
484 | ||
485 | flush_cache_sigtramp(regs->pr); | |
486 | if ((-regs->pr & (L1_CACHE_BYTES-1)) < sizeof(frame->retcode)) | |
487 | flush_cache_sigtramp(regs->pr + L1_CACHE_BYTES); | |
488 | return; | |
489 | ||
490 | give_sigsegv: | |
491 | force_sigsegv(sig, current); | |
492 | } | |
493 | ||
494 | /* | |
495 | * OK, we're invoking a handler | |
496 | */ | |
497 | ||
498 | static void | |
499 | handle_signal(unsigned long sig, struct k_sigaction *ka, siginfo_t *info, | |
500 | sigset_t *oldset, struct pt_regs *regs) | |
501 | { | |
502 | /* Are we from a system call? */ | |
503 | if (regs->tra >= 0) { | |
504 | /* If so, check system call restarting.. */ | |
505 | switch (regs->regs[0]) { | |
506 | case -ERESTARTNOHAND: | |
507 | regs->regs[0] = -EINTR; | |
508 | break; | |
509 | ||
510 | case -ERESTARTSYS: | |
511 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
512 | regs->regs[0] = -EINTR; | |
513 | break; | |
514 | } | |
515 | /* fallthrough */ | |
516 | case -ERESTARTNOINTR: | |
517 | regs->pc -= 2; | |
518 | } | |
519 | } else { | |
520 | /* gUSA handling */ | |
521 | #ifdef CONFIG_PREEMPT | |
522 | unsigned long flags; | |
523 | ||
524 | local_irq_save(flags); | |
525 | #endif | |
526 | if (regs->regs[15] >= 0xc0000000) { | |
527 | int offset = (int)regs->regs[15]; | |
528 | ||
529 | /* Reset stack pointer: clear critical region mark */ | |
530 | regs->regs[15] = regs->regs[1]; | |
531 | if (regs->pc < regs->regs[0]) | |
532 | /* Go to rewind point #1 */ | |
533 | regs->pc = regs->regs[0] + offset - 2; | |
534 | } | |
535 | #ifdef CONFIG_PREEMPT | |
536 | local_irq_restore(flags); | |
537 | #endif | |
538 | } | |
539 | ||
540 | /* Set up the stack frame */ | |
541 | if (ka->sa.sa_flags & SA_SIGINFO) | |
542 | setup_rt_frame(sig, ka, info, oldset, regs); | |
543 | else | |
544 | setup_frame(sig, ka, oldset, regs); | |
545 | ||
546 | if (ka->sa.sa_flags & SA_ONESHOT) | |
547 | ka->sa.sa_handler = SIG_DFL; | |
548 | ||
549 | if (!(ka->sa.sa_flags & SA_NODEFER)) { | |
550 | spin_lock_irq(¤t->sighand->siglock); | |
551 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
552 | sigaddset(¤t->blocked,sig); | |
553 | recalc_sigpending(); | |
554 | spin_unlock_irq(¤t->sighand->siglock); | |
555 | } | |
556 | } | |
557 | ||
558 | /* | |
559 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
560 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
561 | * mistake. | |
562 | * | |
563 | * Note that we go through the signals twice: once to check the signals that | |
564 | * the kernel can handle, and then we build all the user-level signal handling | |
565 | * stack-frames in one go after that. | |
566 | */ | |
567 | int do_signal(struct pt_regs *regs, sigset_t *oldset) | |
568 | { | |
569 | siginfo_t info; | |
570 | int signr; | |
571 | struct k_sigaction ka; | |
572 | ||
573 | /* | |
574 | * We want the common case to go fast, which | |
575 | * is why we may in certain cases get here from | |
576 | * kernel mode. Just return without doing anything | |
577 | * if so. | |
578 | */ | |
579 | if (!user_mode(regs)) | |
580 | return 1; | |
581 | ||
0e6c1f5f | 582 | if (try_to_freeze()) |
1da177e4 LT |
583 | goto no_signal; |
584 | ||
585 | if (!oldset) | |
586 | oldset = ¤t->blocked; | |
587 | ||
588 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
589 | if (signr > 0) { | |
590 | /* Whee! Actually deliver the signal. */ | |
591 | handle_signal(signr, &ka, &info, oldset, regs); | |
592 | return 1; | |
593 | } | |
594 | ||
595 | no_signal: | |
596 | /* Did we come from a system call? */ | |
597 | if (regs->tra >= 0) { | |
598 | /* Restart the system call - no handlers present */ | |
599 | if (regs->regs[0] == -ERESTARTNOHAND || | |
600 | regs->regs[0] == -ERESTARTSYS || | |
601 | regs->regs[0] == -ERESTARTNOINTR || | |
602 | regs->regs[0] == -ERESTART_RESTARTBLOCK) { | |
603 | regs->pc -= 2; | |
604 | } | |
605 | } | |
606 | return 0; | |
607 | } |