x86: signal_64: make setup_sigcontext() similar
[deliverable/linux.git] / arch / x86 / kernel / signal_32.c
CommitLineData
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 */
7e907f48 7#include <linux/list.h>
1da177e4 8
7e907f48
IM
9#include <linux/personality.h>
10#include <linux/binfmts.h>
11#include <linux/suspend.h>
1da177e4 12#include <linux/kernel.h>
7e907f48 13#include <linux/ptrace.h>
1da177e4 14#include <linux/signal.h>
7e907f48
IM
15#include <linux/stddef.h>
16#include <linux/unistd.h>
1da177e4 17#include <linux/errno.h>
7e907f48 18#include <linux/sched.h>
1da177e4 19#include <linux/wait.h>
36a03308 20#include <linux/tracehook.h>
1da177e4 21#include <linux/elf.h>
7e907f48
IM
22#include <linux/smp.h>
23#include <linux/mm.h>
24
1da177e4
LT
25#include <asm/processor.h>
26#include <asm/ucontext.h>
27#include <asm/uaccess.h>
28#include <asm/i387.h>
6c3652ef 29#include <asm/vdso.h>
bb57925f 30#include <asm/syscall.h>
bbc1f698 31#include <asm/syscalls.h>
7e907f48 32
123a6347 33#include "sigframe.h"
1da177e4 34
1da177e4
LT
35#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
36
1a176803
HH
37#define __FIX_EFLAGS (X86_EFLAGS_AC | X86_EFLAGS_OF | \
38 X86_EFLAGS_DF | X86_EFLAGS_TF | X86_EFLAGS_SF | \
39 X86_EFLAGS_ZF | X86_EFLAGS_AF | X86_EFLAGS_PF | \
40 X86_EFLAGS_CF)
41
42#ifdef CONFIG_X86_32
43# define FIX_EFLAGS (__FIX_EFLAGS | X86_EFLAGS_RF)
44#else
45# define FIX_EFLAGS __FIX_EFLAGS
46#endif
47
1da177e4
LT
48/*
49 * Atomically swap in the new signal mask, and wait for a signal.
50 */
51asmlinkage int
52sys_sigsuspend(int history0, int history1, old_sigset_t mask)
53{
1da177e4
LT
54 mask &= _BLOCKABLE;
55 spin_lock_irq(&current->sighand->siglock);
283828f3 56 current->saved_sigmask = current->blocked;
1da177e4
LT
57 siginitset(&current->blocked, mask);
58 recalc_sigpending();
59 spin_unlock_irq(&current->sighand->siglock);
60
283828f3
DH
61 current->state = TASK_INTERRUPTIBLE;
62 schedule();
5a8da0ea 63 set_restore_sigmask();
7e907f48 64
283828f3 65 return -ERESTARTNOHAND;
1da177e4
LT
66}
67
7e907f48 68asmlinkage int
1da177e4
LT
69sys_sigaction(int sig, const struct old_sigaction __user *act,
70 struct old_sigaction __user *oact)
71{
72 struct k_sigaction new_ka, old_ka;
73 int ret;
74
75 if (act) {
76 old_sigset_t mask;
7e907f48 77
1da177e4
LT
78 if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
79 __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
80 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
81 return -EFAULT;
7e907f48 82
1da177e4
LT
83 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
84 __get_user(mask, &act->sa_mask);
85 siginitset(&new_ka.sa.sa_mask, mask);
86 }
87
88 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
89
90 if (!ret && oact) {
91 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
92 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
93 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
94 return -EFAULT;
7e907f48 95
1da177e4
LT
96 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
97 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
98 }
99
100 return ret;
101}
102
7e907f48 103asmlinkage int sys_sigaltstack(unsigned long bx)
1da177e4 104{
7e907f48
IM
105 /*
106 * This is needed to make gcc realize it doesn't own the
107 * "struct pt_regs"
108 */
65ea5b03
PA
109 struct pt_regs *regs = (struct pt_regs *)&bx;
110 const stack_t __user *uss = (const stack_t __user *)bx;
111 stack_t __user *uoss = (stack_t __user *)regs->cx;
1da177e4 112
65ea5b03 113 return do_sigaltstack(uss, uoss, regs->sp);
1da177e4
LT
114}
115
a2e8d3dc
HS
116#define COPY(x) { \
117 err |= __get_user(regs->x, &sc->x); \
118}
119
120#define COPY_SEG(seg) { \
121 unsigned short tmp; \
122 err |= __get_user(tmp, &sc->seg); \
123 regs->seg = tmp; \
124}
125
126#define COPY_SEG_STRICT(seg) { \
127 unsigned short tmp; \
128 err |= __get_user(tmp, &sc->seg); \
129 regs->seg = tmp | 3; \
130}
131
132#define GET_SEG(seg) { \
133 unsigned short tmp; \
134 err |= __get_user(tmp, &sc->seg); \
135 loadsegment(seg, tmp); \
136}
1da177e4
LT
137
138/*
139 * Do a signal return; undo the signal stack.
140 */
1da177e4 141static int
866bc13f
HH
142restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
143 unsigned long *pax)
1da177e4 144{
69e13ad5
HS
145 void __user *buf;
146 unsigned int tmpflags;
1da177e4
LT
147 unsigned int err = 0;
148
149 /* Always make any pending restarted system calls return -EINTR */
150 current_thread_info()->restart_block.fn = do_no_restart_syscall;
151
709110bd 152#ifdef CONFIG_X86_32
464d1a78
JF
153 GET_SEG(gs);
154 COPY_SEG(fs);
1da177e4
LT
155 COPY_SEG(es);
156 COPY_SEG(ds);
709110bd
HS
157#endif /* CONFIG_X86_32 */
158
ac66f3fd
HH
159 COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx);
160 COPY(dx); COPY(cx); COPY(ip);
709110bd
HS
161
162#ifdef CONFIG_X86_64
163 COPY(r8);
164 COPY(r9);
165 COPY(r10);
166 COPY(r11);
167 COPY(r12);
168 COPY(r13);
169 COPY(r14);
170 COPY(r15);
171#endif /* CONFIG_X86_64 */
172
173#ifdef CONFIG_X86_32
1da177e4
LT
174 COPY_SEG_STRICT(cs);
175 COPY_SEG_STRICT(ss);
709110bd
HS
176#else /* !CONFIG_X86_32 */
177 /* Kernel saves and restores only the CS segment register on signals,
178 * which is the bare minimum needed to allow mixed 32/64-bit code.
179 * App's signal handler can save/restore other segments if needed. */
180 COPY_SEG_STRICT(cs);
181#endif /* CONFIG_X86_32 */
7e907f48 182
69e13ad5
HS
183 err |= __get_user(tmpflags, &sc->flags);
184 regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
185 regs->orig_ax = -1; /* disable syscall checks */
7e907f48 186
69e13ad5
HS
187 err |= __get_user(buf, &sc->fpstate);
188 err |= restore_i387_xstate(buf);
1da177e4 189
866bc13f 190 err |= __get_user(*pax, &sc->ax);
1da177e4 191 return err;
1da177e4
LT
192}
193
866bc13f 194asmlinkage unsigned long sys_sigreturn(unsigned long __unused)
1da177e4 195{
7e907f48
IM
196 struct sigframe __user *frame;
197 struct pt_regs *regs;
866bc13f 198 unsigned long ax;
7e907f48
IM
199 sigset_t set;
200
201 regs = (struct pt_regs *) &__unused;
202 frame = (struct sigframe __user *)(regs->sp - 8);
1da177e4
LT
203
204 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
205 goto badframe;
7e907f48 206 if (__get_user(set.sig[0], &frame->sc.oldmask) || (_NSIG_WORDS > 1
1da177e4
LT
207 && __copy_from_user(&set.sig[1], &frame->extramask,
208 sizeof(frame->extramask))))
209 goto badframe;
210
211 sigdelsetmask(&set, ~_BLOCKABLE);
212 spin_lock_irq(&current->sighand->siglock);
213 current->blocked = set;
214 recalc_sigpending();
215 spin_unlock_irq(&current->sighand->siglock);
7e907f48 216
65ea5b03 217 if (restore_sigcontext(regs, &frame->sc, &ax))
1da177e4 218 goto badframe;
65ea5b03 219 return ax;
1da177e4
LT
220
221badframe:
03252919 222 if (show_unhandled_signals && printk_ratelimit()) {
1181f8b5 223 printk("%s%s[%d] bad frame in sigreturn frame:"
97b44ae6 224 "%p ip:%lx sp:%lx oeax:%lx",
19c5870c 225 task_pid_nr(current) > 1 ? KERN_INFO : KERN_EMERG,
65ea5b03
PA
226 current->comm, task_pid_nr(current), frame, regs->ip,
227 regs->sp, regs->orig_ax);
03252919 228 print_vma_addr(" in ", regs->ip);
97b44ae6 229 printk(KERN_CONT "\n");
03252919 230 }
abd4f750 231
1da177e4 232 force_sig(SIGSEGV, current);
7e907f48 233
1da177e4 234 return 0;
7e907f48 235}
1da177e4 236
e6babb6b 237static long do_rt_sigreturn(struct pt_regs *regs)
1da177e4 238{
2d19c458 239 struct rt_sigframe __user *frame;
866bc13f 240 unsigned long ax;
1da177e4 241 sigset_t set;
1da177e4 242
2d19c458 243 frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
1da177e4
LT
244 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
245 goto badframe;
246 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
247 goto badframe;
248
249 sigdelsetmask(&set, ~_BLOCKABLE);
250 spin_lock_irq(&current->sighand->siglock);
251 current->blocked = set;
252 recalc_sigpending();
253 spin_unlock_irq(&current->sighand->siglock);
7e907f48 254
65ea5b03 255 if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
1da177e4
LT
256 goto badframe;
257
65ea5b03 258 if (do_sigaltstack(&frame->uc.uc_stack, NULL, regs->sp) == -EFAULT)
1da177e4
LT
259 goto badframe;
260
65ea5b03 261 return ax;
1da177e4
LT
262
263badframe:
e6babb6b 264 signal_fault(regs, frame, "rt_sigreturn");
1da177e4 265 return 0;
7e907f48 266}
1da177e4 267
e6babb6b
HS
268asmlinkage int sys_rt_sigreturn(unsigned long __unused)
269{
270 struct pt_regs *regs = (struct pt_regs *)&__unused;
271
272 return do_rt_sigreturn(regs);
273}
274
1da177e4
LT
275/*
276 * Set up a signal frame.
277 */
1da177e4 278static int
ab513701 279setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
1da177e4
LT
280 struct pt_regs *regs, unsigned long mask)
281{
282 int tmp, err = 0;
283
65ea5b03 284 err |= __put_user(regs->fs, (unsigned int __user *)&sc->fs);
464d1a78
JF
285 savesegment(gs, tmp);
286 err |= __put_user(tmp, (unsigned int __user *)&sc->gs);
1da177e4 287
65ea5b03
PA
288 err |= __put_user(regs->es, (unsigned int __user *)&sc->es);
289 err |= __put_user(regs->ds, (unsigned int __user *)&sc->ds);
742fa54a
PA
290 err |= __put_user(regs->di, &sc->di);
291 err |= __put_user(regs->si, &sc->si);
292 err |= __put_user(regs->bp, &sc->bp);
293 err |= __put_user(regs->sp, &sc->sp);
294 err |= __put_user(regs->bx, &sc->bx);
295 err |= __put_user(regs->dx, &sc->dx);
296 err |= __put_user(regs->cx, &sc->cx);
297 err |= __put_user(regs->ax, &sc->ax);
1da177e4
LT
298 err |= __put_user(current->thread.trap_no, &sc->trapno);
299 err |= __put_user(current->thread.error_code, &sc->err);
742fa54a 300 err |= __put_user(regs->ip, &sc->ip);
65ea5b03 301 err |= __put_user(regs->cs, (unsigned int __user *)&sc->cs);
742fa54a
PA
302 err |= __put_user(regs->flags, &sc->flags);
303 err |= __put_user(regs->sp, &sc->sp_at_signal);
65ea5b03 304 err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss);
1da177e4 305
4b33669e 306 err |= __put_user(fpstate, &sc->fpstate);
1da177e4
LT
307
308 /* non-iBCS2 extensions.. */
309 err |= __put_user(mask, &sc->oldmask);
310 err |= __put_user(current->thread.cr2, &sc->cr2);
311
312 return err;
313}
314
315/*
316 * Determine which stack to use..
317 */
318static inline void __user *
3c1c7f10 319get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
ab513701 320 void **fpstate)
1da177e4 321{
65ea5b03 322 unsigned long sp;
1da177e4
LT
323
324 /* Default to using normal stack */
65ea5b03 325 sp = regs->sp;
1da177e4 326
83bd0102
RM
327 /*
328 * If we are on the alternate signal stack and would overflow it, don't.
329 * Return an always-bogus address instead so we will die with SIGSEGV.
330 */
65ea5b03 331 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
83bd0102
RM
332 return (void __user *) -1L;
333
1da177e4
LT
334 /* This is the X/Open sanctioned signal stack switching. */
335 if (ka->sa.sa_flags & SA_ONSTACK) {
65ea5b03
PA
336 if (sas_ss_flags(sp) == 0)
337 sp = current->sas_ss_sp + current->sas_ss_size;
7e907f48
IM
338 } else {
339 /* This is the legacy signal stack switching. */
340 if ((regs->ss & 0xffff) != __USER_DS &&
341 !(ka->sa.sa_flags & SA_RESTORER) &&
342 ka->sa.sa_restorer)
343 sp = (unsigned long) ka->sa.sa_restorer;
1da177e4
LT
344 }
345
3c1c7f10
SS
346 if (used_math()) {
347 sp = sp - sig_xstate_size;
348 *fpstate = (struct _fpstate *) sp;
4b33669e
HS
349 if (save_i387_xstate(*fpstate) < 0)
350 return (void __user *)-1L;
3c1c7f10
SS
351 }
352
65ea5b03 353 sp -= frame_size;
7e907f48
IM
354 /*
355 * Align the stack pointer according to the i386 ABI,
356 * i.e. so that on function entry ((sp + 4) & 15) == 0.
357 */
65ea5b03 358 sp = ((sp + 4) & -16ul) - 4;
7e907f48 359
65ea5b03 360 return (void __user *) sp;
1da177e4
LT
361}
362
7e907f48 363static int
1d13024e
HS
364__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
365 struct pt_regs *regs)
1da177e4 366{
1da177e4 367 struct sigframe __user *frame;
7e907f48 368 void __user *restorer;
1da177e4 369 int err = 0;
ab513701 370 void __user *fpstate = NULL;
1da177e4 371
3c1c7f10 372 frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
1da177e4
LT
373
374 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
3d0aedd9 375 return -EFAULT;
1da177e4 376
2ba48e16 377 if (__put_user(sig, &frame->sig))
3d0aedd9 378 return -EFAULT;
1da177e4 379
2ba48e16 380 if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]))
3d0aedd9 381 return -EFAULT;
1da177e4
LT
382
383 if (_NSIG_WORDS > 1) {
2ba48e16
HS
384 if (__copy_to_user(&frame->extramask, &set->sig[1],
385 sizeof(frame->extramask)))
3d0aedd9 386 return -EFAULT;
1da177e4
LT
387 }
388
1a3e4ca4 389 if (current->mm->context.vdso)
6c3652ef 390 restorer = VDSO32_SYMBOL(current->mm->context.vdso, sigreturn);
9fbbd4dd 391 else
ade1af77 392 restorer = &frame->retcode;
1da177e4
LT
393 if (ka->sa.sa_flags & SA_RESTORER)
394 restorer = ka->sa.sa_restorer;
395
396 /* Set up to return from userspace. */
397 err |= __put_user(restorer, &frame->pretcode);
7e907f48 398
1da177e4 399 /*
7e907f48 400 * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80
1da177e4
LT
401 *
402 * WE DO NOT USE IT ANY MORE! It's only left here for historical
403 * reasons and because gdb uses it as a signature to notice
404 * signal handler stack frames.
405 */
406 err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
407 err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
408 err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
409
410 if (err)
3d0aedd9 411 return -EFAULT;
1da177e4
LT
412
413 /* Set up registers for signal handler */
7e907f48
IM
414 regs->sp = (unsigned long)frame;
415 regs->ip = (unsigned long)ka->sa.sa_handler;
416 regs->ax = (unsigned long)sig;
92bc2056
HH
417 regs->dx = 0;
418 regs->cx = 0;
1da177e4 419
65ea5b03
PA
420 regs->ds = __USER_DS;
421 regs->es = __USER_DS;
422 regs->ss = __USER_DS;
423 regs->cs = __USER_CS;
1da177e4 424
283828f3 425 return 0;
1da177e4
LT
426}
427
1d13024e
HS
428static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
429 sigset_t *set, struct pt_regs *regs)
1da177e4 430{
1da177e4 431 struct rt_sigframe __user *frame;
7e907f48 432 void __user *restorer;
1da177e4 433 int err = 0;
ab513701 434 void __user *fpstate = NULL;
1da177e4 435
3c1c7f10 436 frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
1da177e4
LT
437
438 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
3d0aedd9 439 return -EFAULT;
1da177e4 440
13ad7725 441 err |= __put_user(sig, &frame->sig);
1da177e4
LT
442 err |= __put_user(&frame->info, &frame->pinfo);
443 err |= __put_user(&frame->uc, &frame->puc);
444 err |= copy_siginfo_to_user(&frame->info, info);
445 if (err)
3d0aedd9 446 return -EFAULT;
1da177e4
LT
447
448 /* Create the ucontext. */
c37b5efe
SS
449 if (cpu_has_xsave)
450 err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags);
451 else
452 err |= __put_user(0, &frame->uc.uc_flags);
1da177e4
LT
453 err |= __put_user(0, &frame->uc.uc_link);
454 err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp);
65ea5b03 455 err |= __put_user(sas_ss_flags(regs->sp),
1da177e4
LT
456 &frame->uc.uc_stack.ss_flags);
457 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
3c1c7f10 458 err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
7e907f48 459 regs, set->sig[0]);
1da177e4
LT
460 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
461 if (err)
3d0aedd9 462 return -EFAULT;
1da177e4
LT
463
464 /* Set up to return from userspace. */
6c3652ef 465 restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
1da177e4
LT
466 if (ka->sa.sa_flags & SA_RESTORER)
467 restorer = ka->sa.sa_restorer;
468 err |= __put_user(restorer, &frame->pretcode);
7e907f48 469
1da177e4 470 /*
7e907f48 471 * This is movl $__NR_rt_sigreturn, %ax ; int $0x80
1da177e4
LT
472 *
473 * WE DO NOT USE IT ANY MORE! It's only left here for historical
474 * reasons and because gdb uses it as a signature to notice
475 * signal handler stack frames.
476 */
477 err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
478 err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
479 err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
480
481 if (err)
3d0aedd9 482 return -EFAULT;
1da177e4
LT
483
484 /* Set up registers for signal handler */
7e907f48
IM
485 regs->sp = (unsigned long)frame;
486 regs->ip = (unsigned long)ka->sa.sa_handler;
13ad7725 487 regs->ax = (unsigned long)sig;
7e907f48
IM
488 regs->dx = (unsigned long)&frame->info;
489 regs->cx = (unsigned long)&frame->uc;
1da177e4 490
65ea5b03
PA
491 regs->ds = __USER_DS;
492 regs->es = __USER_DS;
493 regs->ss = __USER_DS;
494 regs->cs = __USER_CS;
1da177e4 495
283828f3 496 return 0;
1da177e4
LT
497}
498
499/*
7e907f48
IM
500 * OK, we're invoking a handler:
501 */
8d8c13bd
HS
502static int signr_convert(int sig)
503{
96bf84b7 504#ifdef CONFIG_X86_32
8d8c13bd
HS
505 struct thread_info *info = current_thread_info();
506
507 if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32)
508 return info->exec_domain->signal_invmap[sig];
96bf84b7 509#endif /* CONFIG_X86_32 */
8d8c13bd
HS
510 return sig;
511}
512
cabf5035
HS
513#ifdef CONFIG_X86_32
514
455edbc4 515#define is_ia32 1
4694d239
HS
516#define ia32_setup_frame __setup_frame
517#define ia32_setup_rt_frame __setup_rt_frame
455edbc4 518
cabf5035
HS
519#else /* !CONFIG_X86_32 */
520
521#ifdef CONFIG_IA32_EMULATION
522#define is_ia32 test_thread_flag(TIF_IA32)
523#else /* !CONFIG_IA32_EMULATION */
524#define is_ia32 0
525#endif /* CONFIG_IA32_EMULATION */
526
527#endif /* CONFIG_X86_32 */
528
1d13024e
HS
529static int
530setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
531 sigset_t *set, struct pt_regs *regs)
532{
8d8c13bd 533 int usig = signr_convert(sig);
1d13024e
HS
534 int ret;
535
536 /* Set up the stack frame */
455edbc4
HS
537 if (is_ia32) {
538 if (ka->sa.sa_flags & SA_SIGINFO)
4694d239 539 ret = ia32_setup_rt_frame(usig, ka, info, set, regs);
455edbc4 540 else
4694d239 541 ret = ia32_setup_frame(usig, ka, set, regs);
455edbc4
HS
542 } else
543 ret = __setup_rt_frame(sig, ka, info, set, regs);
1d13024e 544
3d0aedd9
HS
545 if (ret) {
546 force_sigsegv(sig, current);
547 return -EFAULT;
548 }
549
1d13024e
HS
550 return ret;
551}
552
7c1def16 553static int
1da177e4 554handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
ac66f3fd 555 sigset_t *oldset, struct pt_regs *regs)
1da177e4 556{
7c1def16
RM
557 int ret;
558
1da177e4 559 /* Are we from a system call? */
bb57925f 560 if (syscall_get_nr(current, regs) >= 0) {
1da177e4 561 /* If so, check system call restarting.. */
bb57925f 562 switch (syscall_get_error(current, regs)) {
ac66f3fd
HH
563 case -ERESTART_RESTARTBLOCK:
564 case -ERESTARTNOHAND:
565 regs->ax = -EINTR;
566 break;
567
568 case -ERESTARTSYS:
569 if (!(ka->sa.sa_flags & SA_RESTART)) {
65ea5b03 570 regs->ax = -EINTR;
1da177e4 571 break;
ac66f3fd
HH
572 }
573 /* fallthrough */
574 case -ERESTARTNOINTR:
575 regs->ax = regs->orig_ax;
576 regs->ip -= 2;
577 break;
1da177e4
LT
578 }
579 }
580
581 /*
e1f28773
RM
582 * If TF is set due to a debugger (TIF_FORCED_TF), clear the TF
583 * flag so that register information in the sigcontext is correct.
1da177e4 584 */
65ea5b03 585 if (unlikely(regs->flags & X86_EFLAGS_TF) &&
e1f28773 586 likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
65ea5b03 587 regs->flags &= ~X86_EFLAGS_TF;
1da177e4 588
1d13024e 589 ret = setup_rt_frame(sig, ka, info, oldset, regs);
1da177e4 590
7e907f48
IM
591 if (ret)
592 return ret;
7c1def16 593
86d3237c
HS
594#ifdef CONFIG_X86_64
595 /*
596 * This has nothing to do with segment registers,
597 * despite the name. This magic affects uaccess.h
598 * macros' behavior. Reset it to the normal setting.
599 */
600 set_fs(USER_DS);
601#endif
602
8b9c5ff3
RM
603 /*
604 * Clear the direction flag as per the ABI for function entry.
605 */
606 regs->flags &= ~X86_EFLAGS_DF;
607
608 /*
609 * Clear TF when entering the signal handler, but
610 * notify any tracer that was single-stepping it.
611 * The tracer may want to single-step inside the
612 * handler too.
613 */
614 regs->flags &= ~X86_EFLAGS_TF;
8b9c5ff3 615
7e907f48
IM
616 spin_lock_irq(&current->sighand->siglock);
617 sigorsets(&current->blocked, &current->blocked, &ka->sa.sa_mask);
618 if (!(ka->sa.sa_flags & SA_NODEFER))
619 sigaddset(&current->blocked, sig);
620 recalc_sigpending();
621 spin_unlock_irq(&current->sighand->siglock);
622
36a03308
RM
623 tracehook_signal_handler(sig, info, ka, regs,
624 test_thread_flag(TIF_SINGLESTEP));
625
7e907f48 626 return 0;
1da177e4
LT
627}
628
57917752 629#ifdef CONFIG_X86_32
8fcd8e20 630#define NR_restart_syscall __NR_restart_syscall
57917752
HS
631#else /* !CONFIG_X86_32 */
632#define NR_restart_syscall \
633 test_thread_flag(TIF_IA32) ? __NR_ia32_restart_syscall : __NR_restart_syscall
634#endif /* CONFIG_X86_32 */
635
1da177e4
LT
636/*
637 * Note that 'init' is a special process: it doesn't get signals it doesn't
638 * want to handle. Thus you cannot kill init even with a SIGKILL even by
639 * mistake.
640 */
75604d7f 641static void do_signal(struct pt_regs *regs)
1da177e4 642{
ac66f3fd 643 struct k_sigaction ka;
1da177e4
LT
644 siginfo_t info;
645 int signr;
283828f3 646 sigset_t *oldset;
1da177e4
LT
647
648 /*
ac66f3fd
HH
649 * We want the common case to go fast, which is why we may in certain
650 * cases get here from kernel mode. Just return without doing anything
651 * if so.
652 * X86_32: vm86 regs switched out by assembly code before reaching
653 * here, so testing against kernel CS suffices.
1da177e4 654 */
717b594a 655 if (!user_mode(regs))
283828f3 656 return;
1da177e4 657
5a8da0ea 658 if (current_thread_info()->status & TS_RESTORE_SIGMASK)
283828f3
DH
659 oldset = &current->saved_sigmask;
660 else
1da177e4
LT
661 oldset = &current->blocked;
662
663 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
664 if (signr > 0) {
7e907f48
IM
665 /*
666 * Re-enable any watchpoints before delivering the
1da177e4
LT
667 * signal to user space. The processor register will
668 * have been cleared if the watchpoint triggered
669 * inside the kernel.
670 */
ac66f3fd 671 if (current->thread.debugreg7)
0f534093 672 set_debugreg(current->thread.debugreg7, 7);
1da177e4 673
7e907f48 674 /* Whee! Actually deliver the signal. */
283828f3 675 if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
7e907f48 676 /*
5a8da0ea 677 * A signal was successfully delivered; the saved
283828f3
DH
678 * sigmask will have been stored in the signal frame,
679 * and will be restored by sigreturn, so we can simply
5a8da0ea 680 * clear the TS_RESTORE_SIGMASK flag.
7e907f48 681 */
5a8da0ea 682 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
283828f3 683 }
283828f3 684 return;
1da177e4
LT
685 }
686
1da177e4 687 /* Did we come from a system call? */
bb57925f 688 if (syscall_get_nr(current, regs) >= 0) {
1da177e4 689 /* Restart the system call - no handlers present */
bb57925f 690 switch (syscall_get_error(current, regs)) {
283828f3
DH
691 case -ERESTARTNOHAND:
692 case -ERESTARTSYS:
693 case -ERESTARTNOINTR:
65ea5b03
PA
694 regs->ax = regs->orig_ax;
695 regs->ip -= 2;
283828f3
DH
696 break;
697
698 case -ERESTART_RESTARTBLOCK:
8fcd8e20 699 regs->ax = NR_restart_syscall;
65ea5b03 700 regs->ip -= 2;
283828f3 701 break;
1da177e4
LT
702 }
703 }
283828f3 704
ac66f3fd
HH
705 /*
706 * If there's no signal to deliver, we just put the saved sigmask
707 * back.
708 */
5a8da0ea
RM
709 if (current_thread_info()->status & TS_RESTORE_SIGMASK) {
710 current_thread_info()->status &= ~TS_RESTORE_SIGMASK;
283828f3
DH
711 sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
712 }
1da177e4
LT
713}
714
715/*
716 * notification of userspace execution resumption
283828f3 717 * - triggered by the TIF_WORK_MASK flags
1da177e4 718 */
7e907f48
IM
719void
720do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
1da177e4 721{
ee847c54
HS
722#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE)
723 /* notify userspace of pending MCEs */
724 if (thread_info_flags & _TIF_MCE_NOTIFY)
725 mce_notify_user();
726#endif /* CONFIG_X86_64 && CONFIG_X86_MCE */
727
1da177e4 728 /* deal with pending signal delivery */
5a8da0ea 729 if (thread_info_flags & _TIF_SIGPENDING)
283828f3 730 do_signal(regs);
8f4d37ec 731
59e52130
RM
732 if (thread_info_flags & _TIF_NOTIFY_RESUME) {
733 clear_thread_flag(TIF_NOTIFY_RESUME);
734 tracehook_notify_resume(regs);
735 }
736
ee847c54 737#ifdef CONFIG_X86_32
1da177e4 738 clear_thread_flag(TIF_IRET);
ee847c54 739#endif /* CONFIG_X86_32 */
1da177e4 740}
72fa50f4
HS
741
742void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
743{
744 struct task_struct *me = current;
745
746 if (show_unhandled_signals && printk_ratelimit()) {
747 printk(KERN_INFO
748 "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx",
749 me->comm, me->pid, where, frame,
750 regs->ip, regs->sp, regs->orig_ax);
751 print_vma_addr(" in ", regs->ip);
752 printk(KERN_CONT "\n");
753 }
754
755 force_sig(SIGSEGV, me);
756}
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