Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/i386/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 | * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes | |
8 | */ | |
9 | ||
10 | #include <linux/sched.h> | |
11 | #include <linux/mm.h> | |
12 | #include <linux/smp.h> | |
13 | #include <linux/smp_lock.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/signal.h> | |
16 | #include <linux/errno.h> | |
17 | #include <linux/wait.h> | |
18 | #include <linux/unistd.h> | |
19 | #include <linux/stddef.h> | |
20 | #include <linux/personality.h> | |
21 | #include <linux/suspend.h> | |
22 | #include <linux/ptrace.h> | |
23 | #include <linux/elf.h> | |
24 | #include <asm/processor.h> | |
25 | #include <asm/ucontext.h> | |
26 | #include <asm/uaccess.h> | |
27 | #include <asm/i387.h> | |
28 | #include "sigframe.h" | |
29 | ||
30 | #define DEBUG_SIG 0 | |
31 | ||
32 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
33 | ||
34 | /* | |
35 | * Atomically swap in the new signal mask, and wait for a signal. | |
36 | */ | |
37 | asmlinkage int | |
38 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
39 | { | |
1da177e4 LT |
40 | mask &= _BLOCKABLE; |
41 | spin_lock_irq(¤t->sighand->siglock); | |
283828f3 | 42 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
43 | siginitset(¤t->blocked, mask); |
44 | recalc_sigpending(); | |
45 | spin_unlock_irq(¤t->sighand->siglock); | |
46 | ||
283828f3 DH |
47 | current->state = TASK_INTERRUPTIBLE; |
48 | schedule(); | |
49 | set_thread_flag(TIF_RESTORE_SIGMASK); | |
50 | return -ERESTARTNOHAND; | |
1da177e4 LT |
51 | } |
52 | ||
53 | asmlinkage int | |
54 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
55 | struct old_sigaction __user *oact) | |
56 | { | |
57 | struct k_sigaction new_ka, old_ka; | |
58 | int ret; | |
59 | ||
60 | if (act) { | |
61 | old_sigset_t mask; | |
62 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
63 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
64 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
65 | return -EFAULT; | |
66 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
67 | __get_user(mask, &act->sa_mask); | |
68 | siginitset(&new_ka.sa.sa_mask, mask); | |
69 | } | |
70 | ||
71 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
72 | ||
73 | if (!ret && oact) { | |
74 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
75 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
76 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
77 | return -EFAULT; | |
78 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
79 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
80 | } | |
81 | ||
82 | return ret; | |
83 | } | |
84 | ||
85 | asmlinkage int | |
86 | sys_sigaltstack(unsigned long ebx) | |
87 | { | |
88 | /* This is needed to make gcc realize it doesn't own the "struct pt_regs" */ | |
89 | struct pt_regs *regs = (struct pt_regs *)&ebx; | |
90 | const stack_t __user *uss = (const stack_t __user *)ebx; | |
91 | stack_t __user *uoss = (stack_t __user *)regs->ecx; | |
92 | ||
93 | return do_sigaltstack(uss, uoss, regs->esp); | |
94 | } | |
95 | ||
96 | ||
97 | /* | |
98 | * Do a signal return; undo the signal stack. | |
99 | */ | |
100 | ||
101 | static int | |
102 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax) | |
103 | { | |
104 | unsigned int err = 0; | |
105 | ||
106 | /* Always make any pending restarted system calls return -EINTR */ | |
107 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
108 | ||
109 | #define COPY(x) err |= __get_user(regs->x, &sc->x) | |
110 | ||
111 | #define COPY_SEG(seg) \ | |
112 | { unsigned short tmp; \ | |
113 | err |= __get_user(tmp, &sc->seg); \ | |
114 | regs->x##seg = tmp; } | |
115 | ||
116 | #define COPY_SEG_STRICT(seg) \ | |
117 | { unsigned short tmp; \ | |
118 | err |= __get_user(tmp, &sc->seg); \ | |
119 | regs->x##seg = tmp|3; } | |
120 | ||
121 | #define GET_SEG(seg) \ | |
122 | { unsigned short tmp; \ | |
123 | err |= __get_user(tmp, &sc->seg); \ | |
124 | loadsegment(seg,tmp); } | |
125 | ||
8bed51cd CE |
126 | #define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_RF | \ |
127 | X86_EFLAGS_OF | X86_EFLAGS_DF | \ | |
1da177e4 LT |
128 | X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \ |
129 | X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF) | |
130 | ||
f95d47ca | 131 | COPY_SEG(gs); |
1da177e4 LT |
132 | GET_SEG(fs); |
133 | COPY_SEG(es); | |
134 | COPY_SEG(ds); | |
135 | COPY(edi); | |
136 | COPY(esi); | |
137 | COPY(ebp); | |
138 | COPY(esp); | |
139 | COPY(ebx); | |
140 | COPY(edx); | |
141 | COPY(ecx); | |
142 | COPY(eip); | |
143 | COPY_SEG_STRICT(cs); | |
144 | COPY_SEG_STRICT(ss); | |
145 | ||
146 | { | |
147 | unsigned int tmpflags; | |
148 | err |= __get_user(tmpflags, &sc->eflags); | |
149 | regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
150 | regs->orig_eax = -1; /* disable syscall checks */ | |
151 | } | |
152 | ||
153 | { | |
154 | struct _fpstate __user * buf; | |
155 | err |= __get_user(buf, &sc->fpstate); | |
156 | if (buf) { | |
157 | if (!access_ok(VERIFY_READ, buf, sizeof(*buf))) | |
158 | goto badframe; | |
159 | err |= restore_i387(buf); | |
160 | } else { | |
161 | struct task_struct *me = current; | |
162 | if (used_math()) { | |
163 | clear_fpu(me); | |
164 | clear_used_math(); | |
165 | } | |
166 | } | |
167 | } | |
168 | ||
169 | err |= __get_user(*peax, &sc->eax); | |
170 | return err; | |
171 | ||
172 | badframe: | |
173 | return 1; | |
174 | } | |
175 | ||
176 | asmlinkage int sys_sigreturn(unsigned long __unused) | |
177 | { | |
178 | struct pt_regs *regs = (struct pt_regs *) &__unused; | |
179 | struct sigframe __user *frame = (struct sigframe __user *)(regs->esp - 8); | |
180 | sigset_t set; | |
181 | int eax; | |
182 | ||
183 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
184 | goto badframe; | |
185 | if (__get_user(set.sig[0], &frame->sc.oldmask) | |
186 | || (_NSIG_WORDS > 1 | |
187 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
188 | sizeof(frame->extramask)))) | |
189 | goto badframe; | |
190 | ||
191 | sigdelsetmask(&set, ~_BLOCKABLE); | |
192 | spin_lock_irq(¤t->sighand->siglock); | |
193 | current->blocked = set; | |
194 | recalc_sigpending(); | |
195 | spin_unlock_irq(¤t->sighand->siglock); | |
196 | ||
197 | if (restore_sigcontext(regs, &frame->sc, &eax)) | |
198 | goto badframe; | |
199 | return eax; | |
200 | ||
201 | badframe: | |
202 | force_sig(SIGSEGV, current); | |
203 | return 0; | |
204 | } | |
205 | ||
206 | asmlinkage int sys_rt_sigreturn(unsigned long __unused) | |
207 | { | |
208 | struct pt_regs *regs = (struct pt_regs *) &__unused; | |
209 | struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->esp - 4); | |
210 | sigset_t set; | |
211 | int eax; | |
212 | ||
213 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
214 | goto badframe; | |
215 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
216 | goto badframe; | |
217 | ||
218 | sigdelsetmask(&set, ~_BLOCKABLE); | |
219 | spin_lock_irq(¤t->sighand->siglock); | |
220 | current->blocked = set; | |
221 | recalc_sigpending(); | |
222 | spin_unlock_irq(¤t->sighand->siglock); | |
223 | ||
224 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax)) | |
225 | goto badframe; | |
226 | ||
227 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT) | |
228 | goto badframe; | |
229 | ||
230 | return eax; | |
231 | ||
232 | badframe: | |
233 | force_sig(SIGSEGV, current); | |
234 | return 0; | |
235 | } | |
236 | ||
237 | /* | |
238 | * Set up a signal frame. | |
239 | */ | |
240 | ||
241 | static int | |
242 | setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate, | |
243 | struct pt_regs *regs, unsigned long mask) | |
244 | { | |
245 | int tmp, err = 0; | |
246 | ||
f95d47ca | 247 | err |= __put_user(regs->xgs, (unsigned int __user *)&sc->gs); |
4d37e7e3 | 248 | savesegment(fs, tmp); |
1da177e4 LT |
249 | err |= __put_user(tmp, (unsigned int __user *)&sc->fs); |
250 | ||
251 | err |= __put_user(regs->xes, (unsigned int __user *)&sc->es); | |
252 | err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds); | |
253 | err |= __put_user(regs->edi, &sc->edi); | |
254 | err |= __put_user(regs->esi, &sc->esi); | |
255 | err |= __put_user(regs->ebp, &sc->ebp); | |
256 | err |= __put_user(regs->esp, &sc->esp); | |
257 | err |= __put_user(regs->ebx, &sc->ebx); | |
258 | err |= __put_user(regs->edx, &sc->edx); | |
259 | err |= __put_user(regs->ecx, &sc->ecx); | |
260 | err |= __put_user(regs->eax, &sc->eax); | |
261 | err |= __put_user(current->thread.trap_no, &sc->trapno); | |
262 | err |= __put_user(current->thread.error_code, &sc->err); | |
263 | err |= __put_user(regs->eip, &sc->eip); | |
264 | err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs); | |
265 | err |= __put_user(regs->eflags, &sc->eflags); | |
266 | err |= __put_user(regs->esp, &sc->esp_at_signal); | |
267 | err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss); | |
268 | ||
269 | tmp = save_i387(fpstate); | |
270 | if (tmp < 0) | |
271 | err = 1; | |
272 | else | |
273 | err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate); | |
274 | ||
275 | /* non-iBCS2 extensions.. */ | |
276 | err |= __put_user(mask, &sc->oldmask); | |
277 | err |= __put_user(current->thread.cr2, &sc->cr2); | |
278 | ||
279 | return err; | |
280 | } | |
281 | ||
282 | /* | |
283 | * Determine which stack to use.. | |
284 | */ | |
285 | static inline void __user * | |
286 | get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) | |
287 | { | |
288 | unsigned long esp; | |
289 | ||
290 | /* Default to using normal stack */ | |
291 | esp = regs->esp; | |
292 | ||
293 | /* This is the X/Open sanctioned signal stack switching. */ | |
294 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
295 | if (sas_ss_flags(esp) == 0) | |
296 | esp = current->sas_ss_sp + current->sas_ss_size; | |
297 | } | |
298 | ||
299 | /* This is the legacy signal stack switching. */ | |
300 | else if ((regs->xss & 0xffff) != __USER_DS && | |
301 | !(ka->sa.sa_flags & SA_RESTORER) && | |
302 | ka->sa.sa_restorer) { | |
303 | esp = (unsigned long) ka->sa.sa_restorer; | |
304 | } | |
305 | ||
d347f372 MO |
306 | esp -= frame_size; |
307 | /* Align the stack pointer according to the i386 ABI, | |
308 | * i.e. so that on function entry ((sp + 4) & 15) == 0. */ | |
309 | esp = ((esp + 4) & -16ul) - 4; | |
310 | return (void __user *) esp; | |
1da177e4 LT |
311 | } |
312 | ||
313 | /* These symbols are defined with the addresses in the vsyscall page. | |
314 | See vsyscall-sigreturn.S. */ | |
315 | extern void __user __kernel_sigreturn; | |
316 | extern void __user __kernel_rt_sigreturn; | |
317 | ||
7c1def16 RM |
318 | static int setup_frame(int sig, struct k_sigaction *ka, |
319 | sigset_t *set, struct pt_regs * regs) | |
1da177e4 LT |
320 | { |
321 | void __user *restorer; | |
322 | struct sigframe __user *frame; | |
323 | int err = 0; | |
324 | int usig; | |
325 | ||
326 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
327 | ||
328 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
329 | goto give_sigsegv; | |
330 | ||
331 | usig = current_thread_info()->exec_domain | |
332 | && current_thread_info()->exec_domain->signal_invmap | |
333 | && sig < 32 | |
334 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
335 | : sig; | |
336 | ||
337 | err = __put_user(usig, &frame->sig); | |
338 | if (err) | |
339 | goto give_sigsegv; | |
340 | ||
341 | err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]); | |
342 | if (err) | |
343 | goto give_sigsegv; | |
344 | ||
345 | if (_NSIG_WORDS > 1) { | |
346 | err = __copy_to_user(&frame->extramask, &set->sig[1], | |
347 | sizeof(frame->extramask)); | |
348 | if (err) | |
349 | goto give_sigsegv; | |
350 | } | |
351 | ||
e6e5494c | 352 | restorer = (void *)VDSO_SYM(&__kernel_sigreturn); |
1da177e4 LT |
353 | if (ka->sa.sa_flags & SA_RESTORER) |
354 | restorer = ka->sa.sa_restorer; | |
355 | ||
356 | /* Set up to return from userspace. */ | |
357 | err |= __put_user(restorer, &frame->pretcode); | |
358 | ||
359 | /* | |
360 | * This is popl %eax ; movl $,%eax ; int $0x80 | |
361 | * | |
362 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
363 | * reasons and because gdb uses it as a signature to notice | |
364 | * signal handler stack frames. | |
365 | */ | |
366 | err |= __put_user(0xb858, (short __user *)(frame->retcode+0)); | |
367 | err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2)); | |
368 | err |= __put_user(0x80cd, (short __user *)(frame->retcode+6)); | |
369 | ||
370 | if (err) | |
371 | goto give_sigsegv; | |
372 | ||
373 | /* Set up registers for signal handler */ | |
374 | regs->esp = (unsigned long) frame; | |
375 | regs->eip = (unsigned long) ka->sa.sa_handler; | |
376 | regs->eax = (unsigned long) sig; | |
377 | regs->edx = (unsigned long) 0; | |
378 | regs->ecx = (unsigned long) 0; | |
379 | ||
380 | set_fs(USER_DS); | |
381 | regs->xds = __USER_DS; | |
382 | regs->xes = __USER_DS; | |
383 | regs->xss = __USER_DS; | |
384 | regs->xcs = __USER_CS; | |
385 | ||
386 | /* | |
387 | * Clear TF when entering the signal handler, but | |
388 | * notify any tracer that was single-stepping it. | |
389 | * The tracer may want to single-step inside the | |
390 | * handler too. | |
391 | */ | |
392 | regs->eflags &= ~TF_MASK; | |
393 | if (test_thread_flag(TIF_SINGLESTEP)) | |
394 | ptrace_notify(SIGTRAP); | |
395 | ||
396 | #if DEBUG_SIG | |
397 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
398 | current->comm, current->pid, frame, regs->eip, frame->pretcode); | |
399 | #endif | |
400 | ||
283828f3 | 401 | return 0; |
1da177e4 LT |
402 | |
403 | give_sigsegv: | |
404 | force_sigsegv(sig, current); | |
283828f3 | 405 | return -EFAULT; |
1da177e4 LT |
406 | } |
407 | ||
7c1def16 | 408 | static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
1da177e4 LT |
409 | sigset_t *set, struct pt_regs * regs) |
410 | { | |
411 | void __user *restorer; | |
412 | struct rt_sigframe __user *frame; | |
413 | int err = 0; | |
414 | int usig; | |
415 | ||
416 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
417 | ||
418 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
419 | goto give_sigsegv; | |
420 | ||
421 | usig = current_thread_info()->exec_domain | |
422 | && current_thread_info()->exec_domain->signal_invmap | |
423 | && sig < 32 | |
424 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
425 | : sig; | |
426 | ||
427 | err |= __put_user(usig, &frame->sig); | |
428 | err |= __put_user(&frame->info, &frame->pinfo); | |
429 | err |= __put_user(&frame->uc, &frame->puc); | |
430 | err |= copy_siginfo_to_user(&frame->info, info); | |
431 | if (err) | |
432 | goto give_sigsegv; | |
433 | ||
434 | /* Create the ucontext. */ | |
435 | err |= __put_user(0, &frame->uc.uc_flags); | |
436 | err |= __put_user(0, &frame->uc.uc_link); | |
437 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
438 | err |= __put_user(sas_ss_flags(regs->esp), | |
439 | &frame->uc.uc_stack.ss_flags); | |
440 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
441 | err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate, | |
442 | regs, set->sig[0]); | |
443 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
444 | if (err) | |
445 | goto give_sigsegv; | |
446 | ||
447 | /* Set up to return from userspace. */ | |
e6e5494c | 448 | restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn); |
1da177e4 LT |
449 | if (ka->sa.sa_flags & SA_RESTORER) |
450 | restorer = ka->sa.sa_restorer; | |
451 | err |= __put_user(restorer, &frame->pretcode); | |
452 | ||
453 | /* | |
454 | * This is movl $,%eax ; int $0x80 | |
455 | * | |
456 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
457 | * reasons and because gdb uses it as a signature to notice | |
458 | * signal handler stack frames. | |
459 | */ | |
460 | err |= __put_user(0xb8, (char __user *)(frame->retcode+0)); | |
461 | err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1)); | |
462 | err |= __put_user(0x80cd, (short __user *)(frame->retcode+5)); | |
463 | ||
464 | if (err) | |
465 | goto give_sigsegv; | |
466 | ||
467 | /* Set up registers for signal handler */ | |
468 | regs->esp = (unsigned long) frame; | |
469 | regs->eip = (unsigned long) ka->sa.sa_handler; | |
470 | regs->eax = (unsigned long) usig; | |
471 | regs->edx = (unsigned long) &frame->info; | |
472 | regs->ecx = (unsigned long) &frame->uc; | |
473 | ||
474 | set_fs(USER_DS); | |
475 | regs->xds = __USER_DS; | |
476 | regs->xes = __USER_DS; | |
477 | regs->xss = __USER_DS; | |
478 | regs->xcs = __USER_CS; | |
479 | ||
480 | /* | |
481 | * Clear TF when entering the signal handler, but | |
482 | * notify any tracer that was single-stepping it. | |
483 | * The tracer may want to single-step inside the | |
484 | * handler too. | |
485 | */ | |
486 | regs->eflags &= ~TF_MASK; | |
487 | if (test_thread_flag(TIF_SINGLESTEP)) | |
488 | ptrace_notify(SIGTRAP); | |
489 | ||
490 | #if DEBUG_SIG | |
491 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
492 | current->comm, current->pid, frame, regs->eip, frame->pretcode); | |
493 | #endif | |
494 | ||
283828f3 | 495 | return 0; |
1da177e4 LT |
496 | |
497 | give_sigsegv: | |
498 | force_sigsegv(sig, current); | |
283828f3 | 499 | return -EFAULT; |
1da177e4 LT |
500 | } |
501 | ||
502 | /* | |
503 | * OK, we're invoking a handler | |
504 | */ | |
505 | ||
7c1def16 | 506 | static int |
1da177e4 LT |
507 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
508 | sigset_t *oldset, struct pt_regs * regs) | |
509 | { | |
7c1def16 RM |
510 | int ret; |
511 | ||
1da177e4 LT |
512 | /* Are we from a system call? */ |
513 | if (regs->orig_eax >= 0) { | |
514 | /* If so, check system call restarting.. */ | |
515 | switch (regs->eax) { | |
516 | case -ERESTART_RESTARTBLOCK: | |
517 | case -ERESTARTNOHAND: | |
518 | regs->eax = -EINTR; | |
519 | break; | |
520 | ||
521 | case -ERESTARTSYS: | |
522 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
523 | regs->eax = -EINTR; | |
524 | break; | |
525 | } | |
526 | /* fallthrough */ | |
527 | case -ERESTARTNOINTR: | |
528 | regs->eax = regs->orig_eax; | |
529 | regs->eip -= 2; | |
530 | } | |
531 | } | |
532 | ||
533 | /* | |
534 | * If TF is set due to a debugger (PT_DTRACE), clear the TF flag so | |
535 | * that register information in the sigcontext is correct. | |
536 | */ | |
537 | if (unlikely(regs->eflags & TF_MASK) | |
538 | && likely(current->ptrace & PT_DTRACE)) { | |
539 | current->ptrace &= ~PT_DTRACE; | |
540 | regs->eflags &= ~TF_MASK; | |
541 | } | |
542 | ||
543 | /* Set up the stack frame */ | |
544 | if (ka->sa.sa_flags & SA_SIGINFO) | |
7c1def16 | 545 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 546 | else |
7c1def16 | 547 | ret = setup_frame(sig, ka, oldset, regs); |
1da177e4 | 548 | |
283828f3 | 549 | if (ret == 0) { |
1da177e4 LT |
550 | spin_lock_irq(¤t->sighand->siglock); |
551 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
69be8f18 SR |
552 | if (!(ka->sa.sa_flags & SA_NODEFER)) |
553 | sigaddset(¤t->blocked,sig); | |
1da177e4 LT |
554 | recalc_sigpending(); |
555 | spin_unlock_irq(¤t->sighand->siglock); | |
556 | } | |
7c1def16 RM |
557 | |
558 | return ret; | |
1da177e4 LT |
559 | } |
560 | ||
561 | /* | |
562 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
563 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
564 | * mistake. | |
565 | */ | |
283828f3 | 566 | static void fastcall do_signal(struct pt_regs *regs) |
1da177e4 LT |
567 | { |
568 | siginfo_t info; | |
569 | int signr; | |
570 | struct k_sigaction ka; | |
283828f3 | 571 | sigset_t *oldset; |
1da177e4 LT |
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 | |
0998e422 ZA |
577 | * if so. vm86 regs switched out by assembly code |
578 | * before reaching here, so testing against kernel | |
579 | * CS suffices. | |
1da177e4 | 580 | */ |
717b594a | 581 | if (!user_mode(regs)) |
283828f3 | 582 | return; |
1da177e4 | 583 | |
283828f3 DH |
584 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
585 | oldset = ¤t->saved_sigmask; | |
586 | else | |
1da177e4 LT |
587 | oldset = ¤t->blocked; |
588 | ||
589 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
590 | if (signr > 0) { | |
591 | /* Reenable any watchpoints before delivering the | |
592 | * signal to user space. The processor register will | |
593 | * have been cleared if the watchpoint triggered | |
594 | * inside the kernel. | |
595 | */ | |
283828f3 | 596 | if (unlikely(current->thread.debugreg[7])) |
1cc6f12e | 597 | set_debugreg(current->thread.debugreg[7], 7); |
1da177e4 LT |
598 | |
599 | /* Whee! Actually deliver the signal. */ | |
283828f3 DH |
600 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
601 | /* a signal was successfully delivered; the saved | |
602 | * sigmask will have been stored in the signal frame, | |
603 | * and will be restored by sigreturn, so we can simply | |
604 | * clear the TIF_RESTORE_SIGMASK flag */ | |
605 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
606 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
607 | } | |
608 | ||
609 | return; | |
1da177e4 LT |
610 | } |
611 | ||
1da177e4 LT |
612 | /* Did we come from a system call? */ |
613 | if (regs->orig_eax >= 0) { | |
614 | /* Restart the system call - no handlers present */ | |
283828f3 DH |
615 | switch (regs->eax) { |
616 | case -ERESTARTNOHAND: | |
617 | case -ERESTARTSYS: | |
618 | case -ERESTARTNOINTR: | |
1da177e4 LT |
619 | regs->eax = regs->orig_eax; |
620 | regs->eip -= 2; | |
283828f3 DH |
621 | break; |
622 | ||
623 | case -ERESTART_RESTARTBLOCK: | |
1da177e4 LT |
624 | regs->eax = __NR_restart_syscall; |
625 | regs->eip -= 2; | |
283828f3 | 626 | break; |
1da177e4 LT |
627 | } |
628 | } | |
283828f3 DH |
629 | |
630 | /* if there's no signal to deliver, we just put the saved sigmask | |
631 | * back */ | |
632 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { | |
633 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
634 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
635 | } | |
1da177e4 LT |
636 | } |
637 | ||
638 | /* | |
639 | * notification of userspace execution resumption | |
283828f3 | 640 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 LT |
641 | */ |
642 | __attribute__((regparm(3))) | |
283828f3 | 643 | void do_notify_resume(struct pt_regs *regs, void *_unused, |
1da177e4 LT |
644 | __u32 thread_info_flags) |
645 | { | |
646 | /* Pending single-step? */ | |
647 | if (thread_info_flags & _TIF_SINGLESTEP) { | |
648 | regs->eflags |= TF_MASK; | |
649 | clear_thread_flag(TIF_SINGLESTEP); | |
650 | } | |
283828f3 | 651 | |
1da177e4 | 652 | /* deal with pending signal delivery */ |
283828f3 DH |
653 | if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) |
654 | do_signal(regs); | |
1da177e4 LT |
655 | |
656 | clear_thread_flag(TIF_IRET); | |
657 | } |