1 /* 2 * Emulation of Linux signals 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 19 */ 20 #include <stdlib.h> 21 #include <stdio.h> 22 #include <string.h> 23 #include <stdarg.h> 24 #include <signal.h> 25 #include <errno.h> 26 #include <sys/ucontext.h> 27 28 #include "qemu.h" 29 30 //#define DEBUG_SIGNAL 31 32 #define MAX_SIGQUEUE_SIZE 1024 33 34 struct sigqueue { 35 struct sigqueue *next; 36 target_siginfo_t info; 37 }; 38 39 struct emulated_sigaction { 40 struct target_sigaction sa; 41 int pending; /* true if signal is pending */ 42 struct sigqueue *first; 43 struct sigqueue info; /* in order to always have memory for the 44 first signal, we put it here */ 45 }; 46 47 static struct emulated_sigaction sigact_table[TARGET_NSIG]; 48 static struct sigqueue sigqueue_table[MAX_SIGQUEUE_SIZE]; /* siginfo queue */ 49 static struct sigqueue *first_free; /* first free siginfo queue entry */ 50 static int signal_pending; /* non zero if a signal may be pending */ 51 52 static void host_signal_handler(int host_signum, siginfo_t *info, 53 void *puc); 54 55 /* XXX: do it properly */ 56 static inline int host_to_target_signal(int sig) 57 { 58 return sig; 59 } 60 61 static inline int target_to_host_signal(int sig) 62 { 63 return sig; 64 } 65 66 void host_to_target_sigset(target_sigset_t *d, sigset_t *s) 67 { 68 int i; 69 for(i = 0;i < TARGET_NSIG_WORDS; i++) { 70 d->sig[i] = tswapl(((unsigned long *)s)[i]); 71 } 72 } 73 74 void target_to_host_sigset(sigset_t *d, target_sigset_t *s) 75 { 76 int i; 77 for(i = 0;i < TARGET_NSIG_WORDS; i++) { 78 ((unsigned long *)d)[i] = tswapl(s->sig[i]); 79 } 80 } 81 82 void host_to_target_old_sigset(target_ulong *old_sigset, 83 const sigset_t *sigset) 84 { 85 *old_sigset = tswap32(*(unsigned long *)sigset & 0xffffffff); 86 } 87 88 void target_to_host_old_sigset(sigset_t *sigset, 89 const target_ulong *old_sigset) 90 { 91 sigemptyset(sigset); 92 *(unsigned long *)sigset = tswapl(*old_sigset); 93 } 94 95 /* siginfo conversion */ 96 97 static inline void host_to_target_siginfo_noswap(target_siginfo_t *tinfo, 98 const siginfo_t *info) 99 { 100 int sig; 101 sig = host_to_target_signal(info->si_signo); 102 tinfo->si_signo = sig; 103 tinfo->si_errno = 0; 104 tinfo->si_code = 0; 105 if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS) { 106 /* should never come here, but who knows. The information for 107 the target is irrelevant */ 108 tinfo->_sifields._sigfault._addr = 0; 109 } else if (sig >= TARGET_SIGRTMIN) { 110 tinfo->_sifields._rt._pid = info->si_pid; 111 tinfo->_sifields._rt._uid = info->si_uid; 112 /* XXX: potential problem if 64 bit */ 113 tinfo->_sifields._rt._sigval.sival_ptr = 114 (target_ulong)info->si_value.sival_ptr; 115 } 116 } 117 118 static void tswap_siginfo(target_siginfo_t *tinfo, 119 const target_siginfo_t *info) 120 { 121 int sig; 122 sig = info->si_signo; 123 tinfo->si_signo = tswap32(sig); 124 tinfo->si_errno = tswap32(info->si_errno); 125 tinfo->si_code = tswap32(info->si_code); 126 if (sig == SIGILL || sig == SIGFPE || sig == SIGSEGV || sig == SIGBUS) { 127 tinfo->_sifields._sigfault._addr = 128 tswapl(info->_sifields._sigfault._addr); 129 } else if (sig >= TARGET_SIGRTMIN) { 130 tinfo->_sifields._rt._pid = tswap32(info->_sifields._rt._pid); 131 tinfo->_sifields._rt._uid = tswap32(info->_sifields._rt._uid); 132 tinfo->_sifields._rt._sigval.sival_ptr = 133 tswapl(info->_sifields._rt._sigval.sival_ptr); 134 } 135 } 136 137 138 void host_to_target_siginfo(target_siginfo_t *tinfo, const siginfo_t *info) 139 { 140 host_to_target_siginfo_noswap(tinfo, info); 141 tswap_siginfo(tinfo, tinfo); 142 } 143 144 /* XXX: we support only POSIX RT signals are used. */ 145 /* XXX: find a solution for 64 bit (additionnal malloced data is needed) */ 146 void target_to_host_siginfo(siginfo_t *info, const target_siginfo_t *tinfo) 147 { 148 info->si_signo = tswap32(tinfo->si_signo); 149 info->si_errno = tswap32(tinfo->si_errno); 150 info->si_code = tswap32(tinfo->si_code); 151 info->si_pid = tswap32(tinfo->_sifields._rt._pid); 152 info->si_uid = tswap32(tinfo->_sifields._rt._uid); 153 info->si_value.sival_ptr = 154 (void *)tswapl(tinfo->_sifields._rt._sigval.sival_ptr); 155 } 156 157 void signal_init(void) 158 { 159 struct sigaction act; 160 int i; 161 162 /* set all host signal handlers. ALL signals are blocked during 163 the handlers to serialize them. */ 164 sigfillset(&act.sa_mask); 165 act.sa_flags = SA_SIGINFO; 166 act.sa_sigaction = host_signal_handler; 167 for(i = 1; i < NSIG; i++) { 168 sigaction(i, &act, NULL); 169 } 170 171 memset(sigact_table, 0, sizeof(sigact_table)); 172 173 first_free = &sigqueue_table[0]; 174 for(i = 0; i < MAX_SIGQUEUE_SIZE - 1; i++) 175 sigqueue_table[i].next = &sigqueue_table[i + 1]; 176 sigqueue_table[MAX_SIGQUEUE_SIZE - 1].next = NULL; 177 } 178 179 /* signal queue handling */ 180 181 static inline struct sigqueue *alloc_sigqueue(void) 182 { 183 struct sigqueue *q = first_free; 184 if (!q) 185 return NULL; 186 first_free = q->next; 187 return q; 188 } 189 190 static inline void free_sigqueue(struct sigqueue *q) 191 { 192 q->next = first_free; 193 first_free = q; 194 } 195 196 /* abort execution with signal */ 197 void __attribute((noreturn)) force_sig(int sig) 198 { 199 int host_sig; 200 host_sig = target_to_host_signal(sig); 201 fprintf(stderr, "gemu: uncaught target signal %d (%s) - exiting\n", 202 sig, strsignal(host_sig)); 203 #if 1 204 _exit(-host_sig); 205 #else 206 { 207 struct sigaction act; 208 sigemptyset(&act.sa_mask); 209 act.sa_flags = SA_SIGINFO; 210 act.sa_sigaction = SIG_DFL; 211 sigaction(SIGABRT, &act, NULL); 212 abort(); 213 } 214 #endif 215 } 216 217 /* queue a signal so that it will be send to the virtual CPU as soon 218 as possible */ 219 int queue_signal(int sig, target_siginfo_t *info) 220 { 221 struct emulated_sigaction *k; 222 struct sigqueue *q, **pq; 223 target_ulong handler; 224 225 #if defined(DEBUG_SIGNAL) 226 fprintf(stderr, "queue_sigal: sig=%d\n", 227 sig); 228 #endif 229 k = &sigact_table[sig - 1]; 230 handler = k->sa._sa_handler; 231 if (handler == TARGET_SIG_DFL) { 232 /* default handler : ignore some signal. The other are fatal */ 233 if (sig != TARGET_SIGCHLD && 234 sig != TARGET_SIGURG && 235 sig != TARGET_SIGWINCH) { 236 force_sig(sig); 237 } else { 238 return 0; /* indicate ignored */ 239 } 240 } else if (handler == TARGET_SIG_IGN) { 241 /* ignore signal */ 242 return 0; 243 } else if (handler == TARGET_SIG_ERR) { 244 force_sig(sig); 245 } else { 246 pq = &k->first; 247 if (sig < TARGET_SIGRTMIN) { 248 /* if non real time signal, we queue exactly one signal */ 249 if (!k->pending) 250 q = &k->info; 251 else 252 return 0; 253 } else { 254 if (!k->pending) { 255 /* first signal */ 256 q = &k->info; 257 } else { 258 q = alloc_sigqueue(); 259 if (!q) 260 return -EAGAIN; 261 while (*pq != NULL) 262 pq = &(*pq)->next; 263 } 264 } 265 *pq = q; 266 q->info = *info; 267 q->next = NULL; 268 k->pending = 1; 269 /* signal that a new signal is pending */ 270 signal_pending = 1; 271 return 1; /* indicates that the signal was queued */ 272 } 273 } 274 275 #if defined(DEBUG_SIGNAL) 276 #ifdef __i386__ 277 static void dump_regs(struct ucontext *uc) 278 { 279 fprintf(stderr, 280 "EAX=%08x EBX=%08x ECX=%08x EDX=%08x\n" 281 "ESI=%08x EDI=%08x EBP=%08x ESP=%08x\n" 282 "EFL=%08x EIP=%08x\n", 283 uc->uc_mcontext.gregs[EAX], 284 uc->uc_mcontext.gregs[EBX], 285 uc->uc_mcontext.gregs[ECX], 286 uc->uc_mcontext.gregs[EDX], 287 uc->uc_mcontext.gregs[ESI], 288 uc->uc_mcontext.gregs[EDI], 289 uc->uc_mcontext.gregs[EBP], 290 uc->uc_mcontext.gregs[ESP], 291 uc->uc_mcontext.gregs[EFL], 292 uc->uc_mcontext.gregs[EIP]); 293 } 294 #else 295 static void dump_regs(struct ucontext *uc) 296 { 297 } 298 #endif 299 300 #endif 301 302 static void host_signal_handler(int host_signum, siginfo_t *info, 303 void *puc) 304 { 305 int sig; 306 target_siginfo_t tinfo; 307 308 /* the CPU emulator uses some host signals to detect exceptions, 309 we we forward to it some signals */ 310 if (host_signum == SIGSEGV || host_signum == SIGBUS) { 311 if (cpu_x86_signal_handler(host_signum, info, puc)) 312 return; 313 } 314 315 /* get target signal number */ 316 sig = host_to_target_signal(host_signum); 317 if (sig < 1 || sig > TARGET_NSIG) 318 return; 319 #if defined(DEBUG_SIGNAL) 320 fprintf(stderr, "gemu: got signal %d\n", sig); 321 dump_regs(puc); 322 #endif 323 host_to_target_siginfo_noswap(&tinfo, info); 324 if (queue_signal(sig, &tinfo) == 1) { 325 /* interrupt the virtual CPU as soon as possible */ 326 cpu_x86_interrupt(global_env); 327 } 328 } 329 330 int do_sigaction(int sig, const struct target_sigaction *act, 331 struct target_sigaction *oact) 332 { 333 struct emulated_sigaction *k; 334 335 if (sig < 1 || sig > TARGET_NSIG) 336 return -EINVAL; 337 k = &sigact_table[sig - 1]; 338 #if defined(DEBUG_SIGNAL) && 0 339 fprintf(stderr, "sigaction sig=%d act=0x%08x, oact=0x%08x\n", 340 sig, (int)act, (int)oact); 341 #endif 342 if (oact) { 343 oact->_sa_handler = tswapl(k->sa._sa_handler); 344 oact->sa_flags = tswapl(k->sa.sa_flags); 345 oact->sa_restorer = tswapl(k->sa.sa_restorer); 346 oact->sa_mask = k->sa.sa_mask; 347 } 348 if (act) { 349 k->sa._sa_handler = tswapl(act->_sa_handler); 350 k->sa.sa_flags = tswapl(act->sa_flags); 351 k->sa.sa_restorer = tswapl(act->sa_restorer); 352 k->sa.sa_mask = act->sa_mask; 353 } 354 return 0; 355 } 356 357 #ifdef TARGET_I386 358 359 /* from the Linux kernel */ 360 361 struct target_fpreg { 362 uint16_t significand[4]; 363 uint16_t exponent; 364 }; 365 366 struct target_fpxreg { 367 uint16_t significand[4]; 368 uint16_t exponent; 369 uint16_t padding[3]; 370 }; 371 372 struct target_xmmreg { 373 target_ulong element[4]; 374 }; 375 376 struct target_fpstate { 377 /* Regular FPU environment */ 378 target_ulong cw; 379 target_ulong sw; 380 target_ulong tag; 381 target_ulong ipoff; 382 target_ulong cssel; 383 target_ulong dataoff; 384 target_ulong datasel; 385 struct target_fpreg _st[8]; 386 uint16_t status; 387 uint16_t magic; /* 0xffff = regular FPU data only */ 388 389 /* FXSR FPU environment */ 390 target_ulong _fxsr_env[6]; /* FXSR FPU env is ignored */ 391 target_ulong mxcsr; 392 target_ulong reserved; 393 struct target_fpxreg _fxsr_st[8]; /* FXSR FPU reg data is ignored */ 394 struct target_xmmreg _xmm[8]; 395 target_ulong padding[56]; 396 }; 397 398 #define X86_FXSR_MAGIC 0x0000 399 400 struct target_sigcontext { 401 uint16_t gs, __gsh; 402 uint16_t fs, __fsh; 403 uint16_t es, __esh; 404 uint16_t ds, __dsh; 405 target_ulong edi; 406 target_ulong esi; 407 target_ulong ebp; 408 target_ulong esp; 409 target_ulong ebx; 410 target_ulong edx; 411 target_ulong ecx; 412 target_ulong eax; 413 target_ulong trapno; 414 target_ulong err; 415 target_ulong eip; 416 uint16_t cs, __csh; 417 target_ulong eflags; 418 target_ulong esp_at_signal; 419 uint16_t ss, __ssh; 420 target_ulong fpstate; /* pointer */ 421 target_ulong oldmask; 422 target_ulong cr2; 423 }; 424 425 typedef struct target_sigaltstack { 426 target_ulong ss_sp; 427 int ss_flags; 428 target_ulong ss_size; 429 } target_stack_t; 430 431 struct target_ucontext { 432 target_ulong uc_flags; 433 target_ulong uc_link; 434 target_stack_t uc_stack; 435 struct target_sigcontext uc_mcontext; 436 target_sigset_t uc_sigmask; /* mask last for extensibility */ 437 }; 438 439 struct sigframe 440 { 441 target_ulong pretcode; 442 int sig; 443 struct target_sigcontext sc; 444 struct target_fpstate fpstate; 445 target_ulong extramask[TARGET_NSIG_WORDS-1]; 446 char retcode[8]; 447 }; 448 449 struct rt_sigframe 450 { 451 target_ulong pretcode; 452 int sig; 453 target_ulong pinfo; 454 target_ulong puc; 455 struct target_siginfo info; 456 struct target_ucontext uc; 457 struct target_fpstate fpstate; 458 char retcode[8]; 459 }; 460 461 /* 462 * Set up a signal frame. 463 */ 464 465 #define __put_user(x,ptr)\ 466 ({\ 467 int size = sizeof(*ptr);\ 468 switch(size) {\ 469 case 1:\ 470 stb(ptr, (typeof(*ptr))(x));\ 471 break;\ 472 case 2:\ 473 stw(ptr, (typeof(*ptr))(x));\ 474 break;\ 475 case 4:\ 476 stl(ptr, (typeof(*ptr))(x));\ 477 break;\ 478 case 8:\ 479 stq(ptr, (typeof(*ptr))(x));\ 480 break;\ 481 default:\ 482 abort();\ 483 }\ 484 0;\ 485 }) 486 487 #define get_user(val, ptr) (typeof(*ptr))(*(ptr)) 488 489 490 #define __copy_to_user(dst, src, size)\ 491 ({\ 492 memcpy(dst, src, size);\ 493 0;\ 494 }) 495 496 static inline int copy_siginfo_to_user(target_siginfo_t *tinfo, 497 const target_siginfo_t *info) 498 { 499 tswap_siginfo(tinfo, info); 500 return 0; 501 } 502 503 /* XXX: save x87 state */ 504 static int 505 setup_sigcontext(struct target_sigcontext *sc, struct target_fpstate *fpstate, 506 CPUX86State *env, unsigned long mask) 507 { 508 int err = 0; 509 510 err |= __put_user(env->segs[R_GS], (unsigned int *)&sc->gs); 511 err |= __put_user(env->segs[R_FS], (unsigned int *)&sc->fs); 512 err |= __put_user(env->segs[R_ES], (unsigned int *)&sc->es); 513 err |= __put_user(env->segs[R_DS], (unsigned int *)&sc->ds); 514 err |= __put_user(env->regs[R_EDI], &sc->edi); 515 err |= __put_user(env->regs[R_ESI], &sc->esi); 516 err |= __put_user(env->regs[R_EBP], &sc->ebp); 517 err |= __put_user(env->regs[R_ESP], &sc->esp); 518 err |= __put_user(env->regs[R_EBX], &sc->ebx); 519 err |= __put_user(env->regs[R_EDX], &sc->edx); 520 err |= __put_user(env->regs[R_ECX], &sc->ecx); 521 err |= __put_user(env->regs[R_EAX], &sc->eax); 522 err |= __put_user(/*current->thread.trap_no*/ 0, &sc->trapno); 523 err |= __put_user(/*current->thread.error_code*/ 0, &sc->err); 524 err |= __put_user(env->eip, &sc->eip); 525 err |= __put_user(env->segs[R_CS], (unsigned int *)&sc->cs); 526 err |= __put_user(env->eflags, &sc->eflags); 527 err |= __put_user(env->regs[R_ESP], &sc->esp_at_signal); 528 err |= __put_user(env->segs[R_SS], (unsigned int *)&sc->ss); 529 #if 0 530 tmp = save_i387(fpstate); 531 if (tmp < 0) 532 err = 1; 533 else 534 err |= __put_user(tmp ? fpstate : NULL, &sc->fpstate); 535 #else 536 err |= __put_user(0, &sc->fpstate); 537 #endif 538 /* non-iBCS2 extensions.. */ 539 err |= __put_user(mask, &sc->oldmask); 540 err |= __put_user(/*current->thread.cr2*/ 0, &sc->cr2); 541 542 return err; 543 } 544 545 /* 546 * Determine which stack to use.. 547 */ 548 549 static inline void * 550 get_sigframe(struct emulated_sigaction *ka, CPUX86State *env, size_t frame_size) 551 { 552 unsigned long esp; 553 554 /* Default to using normal stack */ 555 esp = env->regs[R_ESP]; 556 #if 0 557 /* This is the X/Open sanctioned signal stack switching. */ 558 if (ka->sa.sa_flags & SA_ONSTACK) { 559 if (sas_ss_flags(esp) == 0) 560 esp = current->sas_ss_sp + current->sas_ss_size; 561 } 562 563 /* This is the legacy signal stack switching. */ 564 else if ((regs->xss & 0xffff) != __USER_DS && 565 !(ka->sa.sa_flags & SA_RESTORER) && 566 ka->sa.sa_restorer) { 567 esp = (unsigned long) ka->sa.sa_restorer; 568 } 569 #endif 570 return (void *)((esp - frame_size) & -8ul); 571 } 572 573 #define TF_MASK TRAP_FLAG 574 575 static void setup_frame(int sig, struct emulated_sigaction *ka, 576 target_sigset_t *set, CPUX86State *env) 577 { 578 struct sigframe *frame; 579 int err = 0; 580 581 frame = get_sigframe(ka, env, sizeof(*frame)); 582 583 #if 0 584 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) 585 goto give_sigsegv; 586 #endif 587 err |= __put_user((/*current->exec_domain 588 && current->exec_domain->signal_invmap 589 && sig < 32 590 ? current->exec_domain->signal_invmap[sig] 591 : */ sig), 592 &frame->sig); 593 if (err) 594 goto give_sigsegv; 595 596 setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0]); 597 if (err) 598 goto give_sigsegv; 599 600 if (TARGET_NSIG_WORDS > 1) { 601 err |= __copy_to_user(frame->extramask, &set->sig[1], 602 sizeof(frame->extramask)); 603 } 604 if (err) 605 goto give_sigsegv; 606 607 /* Set up to return from userspace. If provided, use a stub 608 already in userspace. */ 609 if (ka->sa.sa_flags & TARGET_SA_RESTORER) { 610 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode); 611 } else { 612 err |= __put_user(frame->retcode, &frame->pretcode); 613 /* This is popl %eax ; movl $,%eax ; int $0x80 */ 614 err |= __put_user(0xb858, (short *)(frame->retcode+0)); 615 err |= __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2)); 616 err |= __put_user(0x80cd, (short *)(frame->retcode+6)); 617 } 618 619 if (err) 620 goto give_sigsegv; 621 622 /* Set up registers for signal handler */ 623 env->regs[R_ESP] = (unsigned long) frame; 624 env->eip = (unsigned long) ka->sa._sa_handler; 625 626 cpu_x86_load_seg(env, R_DS, __USER_DS); 627 cpu_x86_load_seg(env, R_ES, __USER_DS); 628 cpu_x86_load_seg(env, R_SS, __USER_DS); 629 cpu_x86_load_seg(env, R_CS, __USER_CS); 630 env->eflags &= ~TF_MASK; 631 632 return; 633 634 give_sigsegv: 635 if (sig == TARGET_SIGSEGV) 636 ka->sa._sa_handler = TARGET_SIG_DFL; 637 force_sig(TARGET_SIGSEGV /* , current */); 638 } 639 640 static void setup_rt_frame(int sig, struct emulated_sigaction *ka, 641 target_siginfo_t *info, 642 target_sigset_t *set, CPUX86State *env) 643 { 644 struct rt_sigframe *frame; 645 int err = 0; 646 647 frame = get_sigframe(ka, env, sizeof(*frame)); 648 649 #if 0 650 if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) 651 goto give_sigsegv; 652 #endif 653 654 err |= __put_user((/*current->exec_domain 655 && current->exec_domain->signal_invmap 656 && sig < 32 657 ? current->exec_domain->signal_invmap[sig] 658 : */sig), 659 &frame->sig); 660 err |= __put_user((target_ulong)&frame->info, &frame->pinfo); 661 err |= __put_user((target_ulong)&frame->uc, &frame->puc); 662 err |= copy_siginfo_to_user(&frame->info, info); 663 if (err) 664 goto give_sigsegv; 665 666 /* Create the ucontext. */ 667 err |= __put_user(0, &frame->uc.uc_flags); 668 err |= __put_user(0, &frame->uc.uc_link); 669 err |= __put_user(/*current->sas_ss_sp*/ 0, &frame->uc.uc_stack.ss_sp); 670 err |= __put_user(/* sas_ss_flags(regs->esp) */ 0, 671 &frame->uc.uc_stack.ss_flags); 672 err |= __put_user(/* current->sas_ss_size */ 0, &frame->uc.uc_stack.ss_size); 673 err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate, 674 env, set->sig[0]); 675 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); 676 if (err) 677 goto give_sigsegv; 678 679 /* Set up to return from userspace. If provided, use a stub 680 already in userspace. */ 681 if (ka->sa.sa_flags & TARGET_SA_RESTORER) { 682 err |= __put_user(ka->sa.sa_restorer, &frame->pretcode); 683 } else { 684 err |= __put_user(frame->retcode, &frame->pretcode); 685 /* This is movl $,%eax ; int $0x80 */ 686 err |= __put_user(0xb8, (char *)(frame->retcode+0)); 687 err |= __put_user(TARGET_NR_rt_sigreturn, (int *)(frame->retcode+1)); 688 err |= __put_user(0x80cd, (short *)(frame->retcode+5)); 689 } 690 691 if (err) 692 goto give_sigsegv; 693 694 /* Set up registers for signal handler */ 695 env->regs[R_ESP] = (unsigned long) frame; 696 env->eip = (unsigned long) ka->sa._sa_handler; 697 698 cpu_x86_load_seg(env, R_DS, __USER_DS); 699 cpu_x86_load_seg(env, R_ES, __USER_DS); 700 cpu_x86_load_seg(env, R_SS, __USER_DS); 701 cpu_x86_load_seg(env, R_CS, __USER_CS); 702 env->eflags &= ~TF_MASK; 703 704 return; 705 706 give_sigsegv: 707 if (sig == TARGET_SIGSEGV) 708 ka->sa._sa_handler = TARGET_SIG_DFL; 709 force_sig(TARGET_SIGSEGV /* , current */); 710 } 711 712 static int 713 restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc, int *peax) 714 { 715 unsigned int err = 0; 716 717 718 719 #define COPY(x) err |= __get_user(regs->x, &sc->x) 720 721 #define COPY_SEG(seg) \ 722 { unsigned short tmp; \ 723 err |= __get_user(tmp, &sc->seg); \ 724 regs->x##seg = tmp; } 725 726 #define COPY_SEG_STRICT(seg) \ 727 { unsigned short tmp; \ 728 err |= __get_user(tmp, &sc->seg); \ 729 regs->x##seg = tmp|3; } 730 731 #define GET_SEG(seg) \ 732 { unsigned short tmp; \ 733 err |= __get_user(tmp, &sc->seg); \ 734 loadsegment(seg,tmp); } 735 736 cpu_x86_load_seg(env, R_GS, lduw(&sc->gs)); 737 cpu_x86_load_seg(env, R_FS, lduw(&sc->fs)); 738 cpu_x86_load_seg(env, R_ES, lduw(&sc->es)); 739 cpu_x86_load_seg(env, R_DS, lduw(&sc->ds)); 740 741 env->regs[R_EDI] = ldl(&sc->edi); 742 env->regs[R_ESI] = ldl(&sc->esi); 743 env->regs[R_EBP] = ldl(&sc->ebp); 744 env->regs[R_ESP] = ldl(&sc->esp); 745 env->regs[R_EBX] = ldl(&sc->ebx); 746 env->regs[R_EDX] = ldl(&sc->edx); 747 env->regs[R_ECX] = ldl(&sc->ecx); 748 env->eip = ldl(&sc->eip); 749 750 cpu_x86_load_seg(env, R_CS, lduw(&sc->cs) | 3); 751 cpu_x86_load_seg(env, R_SS, lduw(&sc->ss) | 3); 752 753 { 754 unsigned int tmpflags; 755 tmpflags = ldl(&sc->eflags); 756 env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5); 757 // regs->orig_eax = -1; /* disable syscall checks */ 758 } 759 760 #if 0 761 { 762 struct _fpstate * buf; 763 err |= __get_user(buf, &sc->fpstate); 764 if (buf) { 765 if (verify_area(VERIFY_READ, buf, sizeof(*buf))) 766 goto badframe; 767 err |= restore_i387(buf); 768 } 769 } 770 #endif 771 *peax = ldl(&sc->eax); 772 return err; 773 #if 0 774 badframe: 775 return 1; 776 #endif 777 } 778 779 long do_sigreturn(CPUX86State *env) 780 { 781 struct sigframe *frame = (struct sigframe *)(env->regs[R_ESP] - 8); 782 target_sigset_t target_set; 783 sigset_t set; 784 int eax, i; 785 786 /* set blocked signals */ 787 target_set.sig[0] = frame->sc.oldmask; 788 for(i = 1; i < TARGET_NSIG_WORDS; i++) 789 target_set.sig[i] = frame->extramask[i - 1]; 790 791 target_to_host_sigset(&set, &target_set); 792 sigprocmask(SIG_SETMASK, &set, NULL); 793 794 /* restore registers */ 795 if (restore_sigcontext(env, &frame->sc, &eax)) 796 goto badframe; 797 return eax; 798 799 badframe: 800 force_sig(TARGET_SIGSEGV); 801 return 0; 802 } 803 804 long do_rt_sigreturn(CPUX86State *env) 805 { 806 struct rt_sigframe *frame = (struct rt_sigframe *)(env->regs[R_ESP] - 4); 807 target_sigset_t target_set; 808 sigset_t set; 809 // stack_t st; 810 int eax; 811 812 #if 0 813 if (verify_area(VERIFY_READ, frame, sizeof(*frame))) 814 goto badframe; 815 #endif 816 memcpy(&target_set, &frame->uc.uc_sigmask, sizeof(target_sigset_t)); 817 818 target_to_host_sigset(&set, &target_set); 819 sigprocmask(SIG_SETMASK, &set, NULL); 820 821 if (restore_sigcontext(env, &frame->uc.uc_mcontext, &eax)) 822 goto badframe; 823 824 #if 0 825 if (__copy_from_user(&st, &frame->uc.uc_stack, sizeof(st))) 826 goto badframe; 827 /* It is more difficult to avoid calling this function than to 828 call it and ignore errors. */ 829 do_sigaltstack(&st, NULL, regs->esp); 830 #endif 831 return eax; 832 833 badframe: 834 force_sig(TARGET_SIGSEGV); 835 return 0; 836 } 837 838 #endif 839 840 void process_pending_signals(void *cpu_env) 841 { 842 int sig; 843 target_ulong handler; 844 sigset_t set, old_set; 845 target_sigset_t target_old_set; 846 struct emulated_sigaction *k; 847 struct sigqueue *q; 848 849 if (!signal_pending) 850 return; 851 852 k = sigact_table; 853 for(sig = 1; sig <= TARGET_NSIG; sig++) { 854 if (k->pending) 855 goto handle_signal; 856 k++; 857 } 858 /* if no signal is pending, just return */ 859 signal_pending = 0; 860 return; 861 862 handle_signal: 863 #ifdef DEBUG_SIGNAL 864 fprintf(stderr, "gemu: process signal %d\n", sig); 865 #endif 866 /* dequeue signal */ 867 q = k->first; 868 k->first = q->next; 869 if (!k->first) 870 k->pending = 0; 871 872 handler = k->sa._sa_handler; 873 if (handler == TARGET_SIG_DFL) { 874 /* default handler : ignore some signal. The other are fatal */ 875 if (sig != TARGET_SIGCHLD && 876 sig != TARGET_SIGURG && 877 sig != TARGET_SIGWINCH) { 878 force_sig(sig); 879 } 880 } else if (handler == TARGET_SIG_IGN) { 881 /* ignore sig */ 882 } else if (handler == TARGET_SIG_ERR) { 883 force_sig(sig); 884 } else { 885 /* compute the blocked signals during the handler execution */ 886 target_to_host_sigset(&set, &k->sa.sa_mask); 887 /* SA_NODEFER indicates that the current signal should not be 888 blocked during the handler */ 889 if (!(k->sa.sa_flags & TARGET_SA_NODEFER)) 890 sigaddset(&set, target_to_host_signal(sig)); 891 892 /* block signals in the handler using Linux */ 893 sigprocmask(SIG_BLOCK, &set, &old_set); 894 /* save the previous blocked signal state to restore it at the 895 end of the signal execution (see do_sigreturn) */ 896 host_to_target_sigset(&target_old_set, &old_set); 897 898 /* prepare the stack frame of the virtual CPU */ 899 if (k->sa.sa_flags & TARGET_SA_SIGINFO) 900 setup_rt_frame(sig, k, &q->info, &target_old_set, cpu_env); 901 else 902 setup_frame(sig, k, &target_old_set, cpu_env); 903 if (k->sa.sa_flags & TARGET_SA_RESETHAND) 904 k->sa._sa_handler = TARGET_SIG_DFL; 905 } 906 if (q != &k->info) 907 free_sigqueue(q); 908 } 909 910 911