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