Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
1da177e4 LT |
2 | * Copyright (C) 1991, 1992 Linus Torvalds |
3 | * | |
4 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
5 | * 2000-06-20 Pentium III FXSR, SSE support by Gareth Hughes | |
6 | */ | |
7 | ||
8 | #include <linux/sched.h> | |
9 | #include <linux/mm.h> | |
10 | #include <linux/smp.h> | |
1da177e4 LT |
11 | #include <linux/kernel.h> |
12 | #include <linux/signal.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/wait.h> | |
15 | #include <linux/unistd.h> | |
16 | #include <linux/stddef.h> | |
17 | #include <linux/personality.h> | |
18 | #include <linux/suspend.h> | |
19 | #include <linux/ptrace.h> | |
20 | #include <linux/elf.h> | |
9fbbd4dd | 21 | #include <linux/binfmts.h> |
1da177e4 LT |
22 | #include <asm/processor.h> |
23 | #include <asm/ucontext.h> | |
24 | #include <asm/uaccess.h> | |
25 | #include <asm/i387.h> | |
56cc623c | 26 | #include "sigframe_32.h" |
1da177e4 LT |
27 | |
28 | #define DEBUG_SIG 0 | |
29 | ||
30 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
31 | ||
32 | /* | |
33 | * Atomically swap in the new signal mask, and wait for a signal. | |
34 | */ | |
35 | asmlinkage int | |
36 | sys_sigsuspend(int history0, int history1, old_sigset_t mask) | |
37 | { | |
1da177e4 LT |
38 | mask &= _BLOCKABLE; |
39 | spin_lock_irq(¤t->sighand->siglock); | |
283828f3 | 40 | current->saved_sigmask = current->blocked; |
1da177e4 LT |
41 | siginitset(¤t->blocked, mask); |
42 | recalc_sigpending(); | |
43 | spin_unlock_irq(¤t->sighand->siglock); | |
44 | ||
283828f3 DH |
45 | current->state = TASK_INTERRUPTIBLE; |
46 | schedule(); | |
47 | set_thread_flag(TIF_RESTORE_SIGMASK); | |
48 | return -ERESTARTNOHAND; | |
1da177e4 LT |
49 | } |
50 | ||
51 | asmlinkage int | |
52 | sys_sigaction(int sig, const struct old_sigaction __user *act, | |
53 | struct old_sigaction __user *oact) | |
54 | { | |
55 | struct k_sigaction new_ka, old_ka; | |
56 | int ret; | |
57 | ||
58 | if (act) { | |
59 | old_sigset_t mask; | |
60 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || | |
61 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || | |
62 | __get_user(new_ka.sa.sa_restorer, &act->sa_restorer)) | |
63 | return -EFAULT; | |
64 | __get_user(new_ka.sa.sa_flags, &act->sa_flags); | |
65 | __get_user(mask, &act->sa_mask); | |
66 | siginitset(&new_ka.sa.sa_mask, mask); | |
67 | } | |
68 | ||
69 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); | |
70 | ||
71 | if (!ret && oact) { | |
72 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || | |
73 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || | |
74 | __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer)) | |
75 | return -EFAULT; | |
76 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags); | |
77 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); | |
78 | } | |
79 | ||
80 | return ret; | |
81 | } | |
82 | ||
83 | asmlinkage int | |
84 | sys_sigaltstack(unsigned long ebx) | |
85 | { | |
86 | /* This is needed to make gcc realize it doesn't own the "struct pt_regs" */ | |
87 | struct pt_regs *regs = (struct pt_regs *)&ebx; | |
88 | const stack_t __user *uss = (const stack_t __user *)ebx; | |
89 | stack_t __user *uoss = (stack_t __user *)regs->ecx; | |
90 | ||
91 | return do_sigaltstack(uss, uoss, regs->esp); | |
92 | } | |
93 | ||
94 | ||
95 | /* | |
96 | * Do a signal return; undo the signal stack. | |
97 | */ | |
98 | ||
99 | static int | |
100 | restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *peax) | |
101 | { | |
102 | unsigned int err = 0; | |
103 | ||
104 | /* Always make any pending restarted system calls return -EINTR */ | |
105 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
106 | ||
107 | #define COPY(x) err |= __get_user(regs->x, &sc->x) | |
108 | ||
109 | #define COPY_SEG(seg) \ | |
110 | { unsigned short tmp; \ | |
111 | err |= __get_user(tmp, &sc->seg); \ | |
112 | regs->x##seg = tmp; } | |
113 | ||
114 | #define COPY_SEG_STRICT(seg) \ | |
115 | { unsigned short tmp; \ | |
116 | err |= __get_user(tmp, &sc->seg); \ | |
117 | regs->x##seg = tmp|3; } | |
118 | ||
119 | #define GET_SEG(seg) \ | |
120 | { unsigned short tmp; \ | |
121 | err |= __get_user(tmp, &sc->seg); \ | |
122 | loadsegment(seg,tmp); } | |
123 | ||
8bed51cd CE |
124 | #define FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_RF | \ |
125 | X86_EFLAGS_OF | X86_EFLAGS_DF | \ | |
1da177e4 LT |
126 | X86_EFLAGS_TF | X86_EFLAGS_SF | X86_EFLAGS_ZF | \ |
127 | X86_EFLAGS_AF | X86_EFLAGS_PF | X86_EFLAGS_CF) | |
128 | ||
464d1a78 JF |
129 | GET_SEG(gs); |
130 | COPY_SEG(fs); | |
1da177e4 LT |
131 | COPY_SEG(es); |
132 | COPY_SEG(ds); | |
133 | COPY(edi); | |
134 | COPY(esi); | |
135 | COPY(ebp); | |
136 | COPY(esp); | |
137 | COPY(ebx); | |
138 | COPY(edx); | |
139 | COPY(ecx); | |
140 | COPY(eip); | |
141 | COPY_SEG_STRICT(cs); | |
142 | COPY_SEG_STRICT(ss); | |
143 | ||
144 | { | |
145 | unsigned int tmpflags; | |
146 | err |= __get_user(tmpflags, &sc->eflags); | |
147 | regs->eflags = (regs->eflags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); | |
148 | regs->orig_eax = -1; /* disable syscall checks */ | |
149 | } | |
150 | ||
151 | { | |
152 | struct _fpstate __user * buf; | |
153 | err |= __get_user(buf, &sc->fpstate); | |
154 | if (buf) { | |
155 | if (!access_ok(VERIFY_READ, buf, sizeof(*buf))) | |
156 | goto badframe; | |
157 | err |= restore_i387(buf); | |
158 | } else { | |
159 | struct task_struct *me = current; | |
160 | if (used_math()) { | |
161 | clear_fpu(me); | |
162 | clear_used_math(); | |
163 | } | |
164 | } | |
165 | } | |
166 | ||
167 | err |= __get_user(*peax, &sc->eax); | |
168 | return err; | |
169 | ||
170 | badframe: | |
171 | return 1; | |
172 | } | |
173 | ||
174 | asmlinkage int sys_sigreturn(unsigned long __unused) | |
175 | { | |
176 | struct pt_regs *regs = (struct pt_regs *) &__unused; | |
177 | struct sigframe __user *frame = (struct sigframe __user *)(regs->esp - 8); | |
178 | sigset_t set; | |
179 | int eax; | |
180 | ||
181 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
182 | goto badframe; | |
183 | if (__get_user(set.sig[0], &frame->sc.oldmask) | |
184 | || (_NSIG_WORDS > 1 | |
185 | && __copy_from_user(&set.sig[1], &frame->extramask, | |
186 | sizeof(frame->extramask)))) | |
187 | goto badframe; | |
188 | ||
189 | sigdelsetmask(&set, ~_BLOCKABLE); | |
190 | spin_lock_irq(¤t->sighand->siglock); | |
191 | current->blocked = set; | |
192 | recalc_sigpending(); | |
193 | spin_unlock_irq(¤t->sighand->siglock); | |
194 | ||
195 | if (restore_sigcontext(regs, &frame->sc, &eax)) | |
196 | goto badframe; | |
197 | return eax; | |
198 | ||
199 | badframe: | |
abd4f750 MAS |
200 | if (show_unhandled_signals && printk_ratelimit()) |
201 | printk("%s%s[%d] bad frame in sigreturn frame:%p eip:%lx" | |
202 | " esp:%lx oeax:%lx\n", | |
19c5870c AD |
203 | task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG, |
204 | current->comm, task_pid_nr(current), frame, regs->eip, | |
abd4f750 MAS |
205 | regs->esp, regs->orig_eax); |
206 | ||
1da177e4 LT |
207 | force_sig(SIGSEGV, current); |
208 | return 0; | |
209 | } | |
210 | ||
211 | asmlinkage int sys_rt_sigreturn(unsigned long __unused) | |
212 | { | |
213 | struct pt_regs *regs = (struct pt_regs *) &__unused; | |
214 | struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(regs->esp - 4); | |
215 | sigset_t set; | |
216 | int eax; | |
217 | ||
218 | if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) | |
219 | goto badframe; | |
220 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
221 | goto badframe; | |
222 | ||
223 | sigdelsetmask(&set, ~_BLOCKABLE); | |
224 | spin_lock_irq(¤t->sighand->siglock); | |
225 | current->blocked = set; | |
226 | recalc_sigpending(); | |
227 | spin_unlock_irq(¤t->sighand->siglock); | |
228 | ||
229 | if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &eax)) | |
230 | goto badframe; | |
231 | ||
232 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->esp) == -EFAULT) | |
233 | goto badframe; | |
234 | ||
235 | return eax; | |
236 | ||
237 | badframe: | |
238 | force_sig(SIGSEGV, current); | |
239 | return 0; | |
240 | } | |
241 | ||
242 | /* | |
243 | * Set up a signal frame. | |
244 | */ | |
245 | ||
246 | static int | |
247 | setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate, | |
248 | struct pt_regs *regs, unsigned long mask) | |
249 | { | |
250 | int tmp, err = 0; | |
251 | ||
464d1a78 JF |
252 | err |= __put_user(regs->xfs, (unsigned int __user *)&sc->fs); |
253 | savesegment(gs, tmp); | |
254 | err |= __put_user(tmp, (unsigned int __user *)&sc->gs); | |
1da177e4 LT |
255 | |
256 | err |= __put_user(regs->xes, (unsigned int __user *)&sc->es); | |
257 | err |= __put_user(regs->xds, (unsigned int __user *)&sc->ds); | |
258 | err |= __put_user(regs->edi, &sc->edi); | |
259 | err |= __put_user(regs->esi, &sc->esi); | |
260 | err |= __put_user(regs->ebp, &sc->ebp); | |
261 | err |= __put_user(regs->esp, &sc->esp); | |
262 | err |= __put_user(regs->ebx, &sc->ebx); | |
263 | err |= __put_user(regs->edx, &sc->edx); | |
264 | err |= __put_user(regs->ecx, &sc->ecx); | |
265 | err |= __put_user(regs->eax, &sc->eax); | |
266 | err |= __put_user(current->thread.trap_no, &sc->trapno); | |
267 | err |= __put_user(current->thread.error_code, &sc->err); | |
268 | err |= __put_user(regs->eip, &sc->eip); | |
269 | err |= __put_user(regs->xcs, (unsigned int __user *)&sc->cs); | |
270 | err |= __put_user(regs->eflags, &sc->eflags); | |
271 | err |= __put_user(regs->esp, &sc->esp_at_signal); | |
272 | err |= __put_user(regs->xss, (unsigned int __user *)&sc->ss); | |
273 | ||
274 | tmp = save_i387(fpstate); | |
275 | if (tmp < 0) | |
276 | err = 1; | |
277 | else | |
278 | err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate); | |
279 | ||
280 | /* non-iBCS2 extensions.. */ | |
281 | err |= __put_user(mask, &sc->oldmask); | |
282 | err |= __put_user(current->thread.cr2, &sc->cr2); | |
283 | ||
284 | return err; | |
285 | } | |
286 | ||
287 | /* | |
288 | * Determine which stack to use.. | |
289 | */ | |
290 | static inline void __user * | |
291 | get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) | |
292 | { | |
293 | unsigned long esp; | |
294 | ||
295 | /* Default to using normal stack */ | |
296 | esp = regs->esp; | |
297 | ||
298 | /* This is the X/Open sanctioned signal stack switching. */ | |
299 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
300 | if (sas_ss_flags(esp) == 0) | |
301 | esp = current->sas_ss_sp + current->sas_ss_size; | |
302 | } | |
303 | ||
304 | /* This is the legacy signal stack switching. */ | |
305 | else if ((regs->xss & 0xffff) != __USER_DS && | |
306 | !(ka->sa.sa_flags & SA_RESTORER) && | |
307 | ka->sa.sa_restorer) { | |
308 | esp = (unsigned long) ka->sa.sa_restorer; | |
309 | } | |
310 | ||
d347f372 MO |
311 | esp -= frame_size; |
312 | /* Align the stack pointer according to the i386 ABI, | |
313 | * i.e. so that on function entry ((sp + 4) & 15) == 0. */ | |
314 | esp = ((esp + 4) & -16ul) - 4; | |
315 | return (void __user *) esp; | |
1da177e4 LT |
316 | } |
317 | ||
318 | /* These symbols are defined with the addresses in the vsyscall page. | |
319 | See vsyscall-sigreturn.S. */ | |
320 | extern void __user __kernel_sigreturn; | |
321 | extern void __user __kernel_rt_sigreturn; | |
322 | ||
7c1def16 RM |
323 | static int setup_frame(int sig, struct k_sigaction *ka, |
324 | sigset_t *set, struct pt_regs * regs) | |
1da177e4 LT |
325 | { |
326 | void __user *restorer; | |
327 | struct sigframe __user *frame; | |
328 | int err = 0; | |
329 | int usig; | |
330 | ||
331 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
332 | ||
333 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
334 | goto give_sigsegv; | |
335 | ||
336 | usig = current_thread_info()->exec_domain | |
337 | && current_thread_info()->exec_domain->signal_invmap | |
338 | && sig < 32 | |
339 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
340 | : sig; | |
341 | ||
342 | err = __put_user(usig, &frame->sig); | |
343 | if (err) | |
344 | goto give_sigsegv; | |
345 | ||
346 | err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]); | |
347 | if (err) | |
348 | goto give_sigsegv; | |
349 | ||
350 | if (_NSIG_WORDS > 1) { | |
351 | err = __copy_to_user(&frame->extramask, &set->sig[1], | |
352 | sizeof(frame->extramask)); | |
353 | if (err) | |
354 | goto give_sigsegv; | |
355 | } | |
356 | ||
9fbbd4dd AK |
357 | if (current->binfmt->hasvdso) |
358 | restorer = (void *)VDSO_SYM(&__kernel_sigreturn); | |
359 | else | |
360 | restorer = (void *)&frame->retcode; | |
1da177e4 LT |
361 | if (ka->sa.sa_flags & SA_RESTORER) |
362 | restorer = ka->sa.sa_restorer; | |
363 | ||
364 | /* Set up to return from userspace. */ | |
365 | err |= __put_user(restorer, &frame->pretcode); | |
366 | ||
367 | /* | |
368 | * This is popl %eax ; movl $,%eax ; int $0x80 | |
369 | * | |
370 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
371 | * reasons and because gdb uses it as a signature to notice | |
372 | * signal handler stack frames. | |
373 | */ | |
374 | err |= __put_user(0xb858, (short __user *)(frame->retcode+0)); | |
375 | err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2)); | |
376 | err |= __put_user(0x80cd, (short __user *)(frame->retcode+6)); | |
377 | ||
378 | if (err) | |
379 | goto give_sigsegv; | |
380 | ||
381 | /* Set up registers for signal handler */ | |
382 | regs->esp = (unsigned long) frame; | |
383 | regs->eip = (unsigned long) ka->sa.sa_handler; | |
384 | regs->eax = (unsigned long) sig; | |
385 | regs->edx = (unsigned long) 0; | |
386 | regs->ecx = (unsigned long) 0; | |
387 | ||
1da177e4 LT |
388 | regs->xds = __USER_DS; |
389 | regs->xes = __USER_DS; | |
390 | regs->xss = __USER_DS; | |
391 | regs->xcs = __USER_CS; | |
392 | ||
393 | /* | |
394 | * Clear TF when entering the signal handler, but | |
395 | * notify any tracer that was single-stepping it. | |
396 | * The tracer may want to single-step inside the | |
397 | * handler too. | |
398 | */ | |
399 | regs->eflags &= ~TF_MASK; | |
400 | if (test_thread_flag(TIF_SINGLESTEP)) | |
401 | ptrace_notify(SIGTRAP); | |
402 | ||
403 | #if DEBUG_SIG | |
404 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
405 | current->comm, current->pid, frame, regs->eip, frame->pretcode); | |
406 | #endif | |
407 | ||
283828f3 | 408 | return 0; |
1da177e4 LT |
409 | |
410 | give_sigsegv: | |
411 | force_sigsegv(sig, current); | |
283828f3 | 412 | return -EFAULT; |
1da177e4 LT |
413 | } |
414 | ||
7c1def16 | 415 | static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
1da177e4 LT |
416 | sigset_t *set, struct pt_regs * regs) |
417 | { | |
418 | void __user *restorer; | |
419 | struct rt_sigframe __user *frame; | |
420 | int err = 0; | |
421 | int usig; | |
422 | ||
423 | frame = get_sigframe(ka, regs, sizeof(*frame)); | |
424 | ||
425 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
426 | goto give_sigsegv; | |
427 | ||
428 | usig = current_thread_info()->exec_domain | |
429 | && current_thread_info()->exec_domain->signal_invmap | |
430 | && sig < 32 | |
431 | ? current_thread_info()->exec_domain->signal_invmap[sig] | |
432 | : sig; | |
433 | ||
434 | err |= __put_user(usig, &frame->sig); | |
435 | err |= __put_user(&frame->info, &frame->pinfo); | |
436 | err |= __put_user(&frame->uc, &frame->puc); | |
437 | err |= copy_siginfo_to_user(&frame->info, info); | |
438 | if (err) | |
439 | goto give_sigsegv; | |
440 | ||
441 | /* Create the ucontext. */ | |
442 | err |= __put_user(0, &frame->uc.uc_flags); | |
443 | err |= __put_user(0, &frame->uc.uc_link); | |
444 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
445 | err |= __put_user(sas_ss_flags(regs->esp), | |
446 | &frame->uc.uc_stack.ss_flags); | |
447 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
448 | err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate, | |
449 | regs, set->sig[0]); | |
450 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); | |
451 | if (err) | |
452 | goto give_sigsegv; | |
453 | ||
454 | /* Set up to return from userspace. */ | |
e6e5494c | 455 | restorer = (void *)VDSO_SYM(&__kernel_rt_sigreturn); |
1da177e4 LT |
456 | if (ka->sa.sa_flags & SA_RESTORER) |
457 | restorer = ka->sa.sa_restorer; | |
458 | err |= __put_user(restorer, &frame->pretcode); | |
459 | ||
460 | /* | |
461 | * This is movl $,%eax ; int $0x80 | |
462 | * | |
463 | * WE DO NOT USE IT ANY MORE! It's only left here for historical | |
464 | * reasons and because gdb uses it as a signature to notice | |
465 | * signal handler stack frames. | |
466 | */ | |
467 | err |= __put_user(0xb8, (char __user *)(frame->retcode+0)); | |
468 | err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1)); | |
469 | err |= __put_user(0x80cd, (short __user *)(frame->retcode+5)); | |
470 | ||
471 | if (err) | |
472 | goto give_sigsegv; | |
473 | ||
474 | /* Set up registers for signal handler */ | |
475 | regs->esp = (unsigned long) frame; | |
476 | regs->eip = (unsigned long) ka->sa.sa_handler; | |
477 | regs->eax = (unsigned long) usig; | |
478 | regs->edx = (unsigned long) &frame->info; | |
479 | regs->ecx = (unsigned long) &frame->uc; | |
480 | ||
1da177e4 LT |
481 | regs->xds = __USER_DS; |
482 | regs->xes = __USER_DS; | |
483 | regs->xss = __USER_DS; | |
484 | regs->xcs = __USER_CS; | |
485 | ||
486 | /* | |
487 | * Clear TF when entering the signal handler, but | |
488 | * notify any tracer that was single-stepping it. | |
489 | * The tracer may want to single-step inside the | |
490 | * handler too. | |
491 | */ | |
492 | regs->eflags &= ~TF_MASK; | |
493 | if (test_thread_flag(TIF_SINGLESTEP)) | |
494 | ptrace_notify(SIGTRAP); | |
495 | ||
496 | #if DEBUG_SIG | |
497 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", | |
498 | current->comm, current->pid, frame, regs->eip, frame->pretcode); | |
499 | #endif | |
500 | ||
283828f3 | 501 | return 0; |
1da177e4 LT |
502 | |
503 | give_sigsegv: | |
504 | force_sigsegv(sig, current); | |
283828f3 | 505 | return -EFAULT; |
1da177e4 LT |
506 | } |
507 | ||
508 | /* | |
509 | * OK, we're invoking a handler | |
510 | */ | |
511 | ||
7c1def16 | 512 | static int |
1da177e4 LT |
513 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, |
514 | sigset_t *oldset, struct pt_regs * regs) | |
515 | { | |
7c1def16 RM |
516 | int ret; |
517 | ||
1da177e4 LT |
518 | /* Are we from a system call? */ |
519 | if (regs->orig_eax >= 0) { | |
520 | /* If so, check system call restarting.. */ | |
521 | switch (regs->eax) { | |
522 | case -ERESTART_RESTARTBLOCK: | |
523 | case -ERESTARTNOHAND: | |
524 | regs->eax = -EINTR; | |
525 | break; | |
526 | ||
527 | case -ERESTARTSYS: | |
528 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
529 | regs->eax = -EINTR; | |
530 | break; | |
531 | } | |
532 | /* fallthrough */ | |
533 | case -ERESTARTNOINTR: | |
534 | regs->eax = regs->orig_eax; | |
535 | regs->eip -= 2; | |
536 | } | |
537 | } | |
538 | ||
539 | /* | |
540 | * If TF is set due to a debugger (PT_DTRACE), clear the TF flag so | |
541 | * that register information in the sigcontext is correct. | |
542 | */ | |
543 | if (unlikely(regs->eflags & TF_MASK) | |
544 | && likely(current->ptrace & PT_DTRACE)) { | |
545 | current->ptrace &= ~PT_DTRACE; | |
546 | regs->eflags &= ~TF_MASK; | |
547 | } | |
548 | ||
549 | /* Set up the stack frame */ | |
550 | if (ka->sa.sa_flags & SA_SIGINFO) | |
7c1def16 | 551 | ret = setup_rt_frame(sig, ka, info, oldset, regs); |
1da177e4 | 552 | else |
7c1def16 | 553 | ret = setup_frame(sig, ka, oldset, regs); |
1da177e4 | 554 | |
283828f3 | 555 | if (ret == 0) { |
1da177e4 LT |
556 | spin_lock_irq(¤t->sighand->siglock); |
557 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); | |
69be8f18 SR |
558 | if (!(ka->sa.sa_flags & SA_NODEFER)) |
559 | sigaddset(¤t->blocked,sig); | |
1da177e4 LT |
560 | recalc_sigpending(); |
561 | spin_unlock_irq(¤t->sighand->siglock); | |
562 | } | |
7c1def16 RM |
563 | |
564 | return ret; | |
1da177e4 LT |
565 | } |
566 | ||
567 | /* | |
568 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
569 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
570 | * mistake. | |
571 | */ | |
283828f3 | 572 | static void fastcall do_signal(struct pt_regs *regs) |
1da177e4 LT |
573 | { |
574 | siginfo_t info; | |
575 | int signr; | |
576 | struct k_sigaction ka; | |
283828f3 | 577 | sigset_t *oldset; |
1da177e4 LT |
578 | |
579 | /* | |
580 | * We want the common case to go fast, which | |
581 | * is why we may in certain cases get here from | |
582 | * kernel mode. Just return without doing anything | |
0998e422 ZA |
583 | * if so. vm86 regs switched out by assembly code |
584 | * before reaching here, so testing against kernel | |
585 | * CS suffices. | |
1da177e4 | 586 | */ |
717b594a | 587 | if (!user_mode(regs)) |
283828f3 | 588 | return; |
1da177e4 | 589 | |
283828f3 DH |
590 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
591 | oldset = ¤t->saved_sigmask; | |
592 | else | |
1da177e4 LT |
593 | oldset = ¤t->blocked; |
594 | ||
595 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
596 | if (signr > 0) { | |
27b46d76 | 597 | /* Re-enable any watchpoints before delivering the |
1da177e4 LT |
598 | * signal to user space. The processor register will |
599 | * have been cleared if the watchpoint triggered | |
600 | * inside the kernel. | |
601 | */ | |
283828f3 | 602 | if (unlikely(current->thread.debugreg[7])) |
1cc6f12e | 603 | set_debugreg(current->thread.debugreg[7], 7); |
1da177e4 LT |
604 | |
605 | /* Whee! Actually deliver the signal. */ | |
283828f3 DH |
606 | if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { |
607 | /* a signal was successfully delivered; the saved | |
608 | * sigmask will have been stored in the signal frame, | |
609 | * and will be restored by sigreturn, so we can simply | |
610 | * clear the TIF_RESTORE_SIGMASK flag */ | |
611 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) | |
612 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
613 | } | |
614 | ||
615 | return; | |
1da177e4 LT |
616 | } |
617 | ||
1da177e4 LT |
618 | /* Did we come from a system call? */ |
619 | if (regs->orig_eax >= 0) { | |
620 | /* Restart the system call - no handlers present */ | |
283828f3 DH |
621 | switch (regs->eax) { |
622 | case -ERESTARTNOHAND: | |
623 | case -ERESTARTSYS: | |
624 | case -ERESTARTNOINTR: | |
1da177e4 LT |
625 | regs->eax = regs->orig_eax; |
626 | regs->eip -= 2; | |
283828f3 DH |
627 | break; |
628 | ||
629 | case -ERESTART_RESTARTBLOCK: | |
1da177e4 LT |
630 | regs->eax = __NR_restart_syscall; |
631 | regs->eip -= 2; | |
283828f3 | 632 | break; |
1da177e4 LT |
633 | } |
634 | } | |
283828f3 DH |
635 | |
636 | /* if there's no signal to deliver, we just put the saved sigmask | |
637 | * back */ | |
638 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { | |
639 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
640 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
641 | } | |
1da177e4 LT |
642 | } |
643 | ||
644 | /* | |
645 | * notification of userspace execution resumption | |
283828f3 | 646 | * - triggered by the TIF_WORK_MASK flags |
1da177e4 LT |
647 | */ |
648 | __attribute__((regparm(3))) | |
283828f3 | 649 | void do_notify_resume(struct pt_regs *regs, void *_unused, |
1da177e4 LT |
650 | __u32 thread_info_flags) |
651 | { | |
652 | /* Pending single-step? */ | |
653 | if (thread_info_flags & _TIF_SINGLESTEP) { | |
654 | regs->eflags |= TF_MASK; | |
655 | clear_thread_flag(TIF_SINGLESTEP); | |
656 | } | |
283828f3 | 657 | |
1da177e4 | 658 | /* deal with pending signal delivery */ |
283828f3 DH |
659 | if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) |
660 | do_signal(regs); | |
1da177e4 LT |
661 | |
662 | clear_thread_flag(TIF_IRET); | |
663 | } |