1 /* 2 * linux/arch/m68k/kernel/signal.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file COPYING in the main directory of this archive 8 * for more details. 9 */ 10 11 /* 12 * Linux/m68k support by Hamish Macdonald 13 * 14 * 68060 fixes by Jesper Skov 15 * 16 * 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab 17 * 18 * mathemu support by Roman Zippel 19 * (Note: fpstate in the signal context is completely ignored for the emulator 20 * and the internal floating point format is put on stack) 21 */ 22 23 /* 24 * ++roman (07/09/96): implemented signal stacks (specially for tosemu on 25 * Atari :-) Current limitation: Only one sigstack can be active at one time. 26 * If a second signal with SA_ONSTACK set arrives while working on a sigstack, 27 * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested 28 * signal handlers! 29 */ 30 31 #include <linux/sched.h> 32 #include <linux/mm.h> 33 #include <linux/kernel.h> 34 #include <linux/signal.h> 35 #include <linux/syscalls.h> 36 #include <linux/errno.h> 37 #include <linux/wait.h> 38 #include <linux/ptrace.h> 39 #include <linux/unistd.h> 40 #include <linux/stddef.h> 41 #include <linux/highuid.h> 42 #include <linux/personality.h> 43 #include <linux/tty.h> 44 #include <linux/binfmts.h> 45 #include <linux/extable.h> 46 #include <linux/tracehook.h> 47 48 #include <asm/setup.h> 49 #include <linux/uaccess.h> 50 #include <asm/traps.h> 51 #include <asm/ucontext.h> 52 #include <asm/cacheflush.h> 53 54 #ifdef CONFIG_MMU 55 56 /* 57 * Handle the slight differences in classic 68k and ColdFire trap frames. 58 */ 59 #ifdef CONFIG_COLDFIRE 60 #define FORMAT 4 61 #define FMT4SIZE 0 62 #else 63 #define FORMAT 0 64 #define FMT4SIZE sizeof_field(struct frame, un.fmt4) 65 #endif 66 67 static const int frame_size_change[16] = { 68 [1] = -1, /* sizeof_field(struct frame, un.fmt1), */ 69 [2] = sizeof_field(struct frame, un.fmt2), 70 [3] = sizeof_field(struct frame, un.fmt3), 71 [4] = FMT4SIZE, 72 [5] = -1, /* sizeof_field(struct frame, un.fmt5), */ 73 [6] = -1, /* sizeof_field(struct frame, un.fmt6), */ 74 [7] = sizeof_field(struct frame, un.fmt7), 75 [8] = -1, /* sizeof_field(struct frame, un.fmt8), */ 76 [9] = sizeof_field(struct frame, un.fmt9), 77 [10] = sizeof_field(struct frame, un.fmta), 78 [11] = sizeof_field(struct frame, un.fmtb), 79 [12] = -1, /* sizeof_field(struct frame, un.fmtc), */ 80 [13] = -1, /* sizeof_field(struct frame, un.fmtd), */ 81 [14] = -1, /* sizeof_field(struct frame, un.fmte), */ 82 [15] = -1, /* sizeof_field(struct frame, un.fmtf), */ 83 }; 84 85 static inline int frame_extra_sizes(int f) 86 { 87 return frame_size_change[f]; 88 } 89 90 int fixup_exception(struct pt_regs *regs) 91 { 92 const struct exception_table_entry *fixup; 93 struct pt_regs *tregs; 94 95 /* Are we prepared to handle this kernel fault? */ 96 fixup = search_exception_tables(regs->pc); 97 if (!fixup) 98 return 0; 99 100 /* Create a new four word stack frame, discarding the old one. */ 101 regs->stkadj = frame_extra_sizes(regs->format); 102 tregs = (struct pt_regs *)((long)regs + regs->stkadj); 103 tregs->vector = regs->vector; 104 tregs->format = FORMAT; 105 tregs->pc = fixup->fixup; 106 tregs->sr = regs->sr; 107 108 return 1; 109 } 110 111 static inline void push_cache (unsigned long vaddr) 112 { 113 /* 114 * Using the old cache_push_v() was really a big waste. 115 * 116 * What we are trying to do is to flush 8 bytes to ram. 117 * Flushing 2 cache lines of 16 bytes is much cheaper than 118 * flushing 1 or 2 pages, as previously done in 119 * cache_push_v(). 120 * Jes 121 */ 122 if (CPU_IS_040) { 123 unsigned long temp; 124 125 __asm__ __volatile__ (".chip 68040\n\t" 126 "nop\n\t" 127 "ptestr (%1)\n\t" 128 "movec %%mmusr,%0\n\t" 129 ".chip 68k" 130 : "=r" (temp) 131 : "a" (vaddr)); 132 133 temp &= PAGE_MASK; 134 temp |= vaddr & ~PAGE_MASK; 135 136 __asm__ __volatile__ (".chip 68040\n\t" 137 "nop\n\t" 138 "cpushl %%bc,(%0)\n\t" 139 ".chip 68k" 140 : : "a" (temp)); 141 } 142 else if (CPU_IS_060) { 143 unsigned long temp; 144 __asm__ __volatile__ (".chip 68060\n\t" 145 "plpar (%0)\n\t" 146 ".chip 68k" 147 : "=a" (temp) 148 : "0" (vaddr)); 149 __asm__ __volatile__ (".chip 68060\n\t" 150 "cpushl %%bc,(%0)\n\t" 151 ".chip 68k" 152 : : "a" (temp)); 153 } else if (!CPU_IS_COLDFIRE) { 154 /* 155 * 68030/68020 have no writeback cache; 156 * still need to clear icache. 157 * Note that vaddr is guaranteed to be long word aligned. 158 */ 159 unsigned long temp; 160 asm volatile ("movec %%cacr,%0" : "=r" (temp)); 161 temp += 4; 162 asm volatile ("movec %0,%%caar\n\t" 163 "movec %1,%%cacr" 164 : : "r" (vaddr), "r" (temp)); 165 asm volatile ("movec %0,%%caar\n\t" 166 "movec %1,%%cacr" 167 : : "r" (vaddr + 4), "r" (temp)); 168 } else { 169 /* CPU_IS_COLDFIRE */ 170 #if defined(CONFIG_CACHE_COPYBACK) 171 flush_cf_dcache(0, DCACHE_MAX_ADDR); 172 #endif 173 /* Invalidate instruction cache for the pushed bytes */ 174 clear_cf_icache(vaddr, vaddr + 8); 175 } 176 } 177 178 static inline void adjustformat(struct pt_regs *regs) 179 { 180 } 181 182 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 183 { 184 } 185 186 #else /* CONFIG_MMU */ 187 188 void ret_from_user_signal(void); 189 void ret_from_user_rt_signal(void); 190 191 static inline int frame_extra_sizes(int f) 192 { 193 /* No frame size adjustments required on non-MMU CPUs */ 194 return 0; 195 } 196 197 static inline void adjustformat(struct pt_regs *regs) 198 { 199 /* 200 * set format byte to make stack appear modulo 4, which it will 201 * be when doing the rte 202 */ 203 regs->format = 0x4; 204 } 205 206 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 207 { 208 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5; 209 } 210 211 static inline void push_cache(unsigned long vaddr) 212 { 213 } 214 215 #endif /* CONFIG_MMU */ 216 217 /* 218 * Do a signal return; undo the signal stack. 219 * 220 * Keep the return code on the stack quadword aligned! 221 * That makes the cache flush below easier. 222 */ 223 224 struct sigframe 225 { 226 char __user *pretcode; 227 int sig; 228 int code; 229 struct sigcontext __user *psc; 230 char retcode[8]; 231 unsigned long extramask[_NSIG_WORDS-1]; 232 struct sigcontext sc; 233 }; 234 235 struct rt_sigframe 236 { 237 char __user *pretcode; 238 int sig; 239 struct siginfo __user *pinfo; 240 void __user *puc; 241 char retcode[8]; 242 struct siginfo info; 243 struct ucontext uc; 244 }; 245 246 #define FPCONTEXT_SIZE 216 247 #define uc_fpstate uc_filler[0] 248 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] 249 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] 250 251 #ifdef CONFIG_FPU 252 253 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ 254 255 static inline int restore_fpu_state(struct sigcontext *sc) 256 { 257 int err = 1; 258 259 if (FPU_IS_EMU) { 260 /* restore registers */ 261 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); 262 memcpy(current->thread.fp, sc->sc_fpregs, 24); 263 return 0; 264 } 265 266 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 267 /* Verify the frame format. */ 268 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 269 (sc->sc_fpstate[0] != fpu_version)) 270 goto out; 271 if (CPU_IS_020_OR_030) { 272 if (m68k_fputype & FPU_68881 && 273 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) 274 goto out; 275 if (m68k_fputype & FPU_68882 && 276 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) 277 goto out; 278 } else if (CPU_IS_040) { 279 if (!(sc->sc_fpstate[1] == 0x00 || 280 sc->sc_fpstate[1] == 0x28 || 281 sc->sc_fpstate[1] == 0x60)) 282 goto out; 283 } else if (CPU_IS_060) { 284 if (!(sc->sc_fpstate[3] == 0x00 || 285 sc->sc_fpstate[3] == 0x60 || 286 sc->sc_fpstate[3] == 0xe0)) 287 goto out; 288 } else if (CPU_IS_COLDFIRE) { 289 if (!(sc->sc_fpstate[0] == 0x00 || 290 sc->sc_fpstate[0] == 0x05 || 291 sc->sc_fpstate[0] == 0xe5)) 292 goto out; 293 } else 294 goto out; 295 296 if (CPU_IS_COLDFIRE) { 297 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t" 298 "fmovel %1,%%fpcr\n\t" 299 "fmovel %2,%%fpsr\n\t" 300 "fmovel %3,%%fpiar" 301 : /* no outputs */ 302 : "m" (sc->sc_fpregs[0]), 303 "m" (sc->sc_fpcntl[0]), 304 "m" (sc->sc_fpcntl[1]), 305 "m" (sc->sc_fpcntl[2])); 306 } else { 307 __asm__ volatile (".chip 68k/68881\n\t" 308 "fmovemx %0,%%fp0-%%fp1\n\t" 309 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 310 ".chip 68k" 311 : /* no outputs */ 312 : "m" (*sc->sc_fpregs), 313 "m" (*sc->sc_fpcntl)); 314 } 315 } 316 317 if (CPU_IS_COLDFIRE) { 318 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate)); 319 } else { 320 __asm__ volatile (".chip 68k/68881\n\t" 321 "frestore %0\n\t" 322 ".chip 68k" 323 : : "m" (*sc->sc_fpstate)); 324 } 325 err = 0; 326 327 out: 328 return err; 329 } 330 331 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 332 { 333 unsigned char fpstate[FPCONTEXT_SIZE]; 334 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 335 fpregset_t fpregs; 336 int err = 1; 337 338 if (FPU_IS_EMU) { 339 /* restore fpu control register */ 340 if (__copy_from_user(current->thread.fpcntl, 341 uc->uc_mcontext.fpregs.f_fpcntl, 12)) 342 goto out; 343 /* restore all other fpu register */ 344 if (__copy_from_user(current->thread.fp, 345 uc->uc_mcontext.fpregs.f_fpregs, 96)) 346 goto out; 347 return 0; 348 } 349 350 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate)) 351 goto out; 352 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 353 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 354 context_size = fpstate[1]; 355 /* Verify the frame format. */ 356 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 357 (fpstate[0] != fpu_version)) 358 goto out; 359 if (CPU_IS_020_OR_030) { 360 if (m68k_fputype & FPU_68881 && 361 !(context_size == 0x18 || context_size == 0xb4)) 362 goto out; 363 if (m68k_fputype & FPU_68882 && 364 !(context_size == 0x38 || context_size == 0xd4)) 365 goto out; 366 } else if (CPU_IS_040) { 367 if (!(context_size == 0x00 || 368 context_size == 0x28 || 369 context_size == 0x60)) 370 goto out; 371 } else if (CPU_IS_060) { 372 if (!(fpstate[3] == 0x00 || 373 fpstate[3] == 0x60 || 374 fpstate[3] == 0xe0)) 375 goto out; 376 } else if (CPU_IS_COLDFIRE) { 377 if (!(fpstate[3] == 0x00 || 378 fpstate[3] == 0x05 || 379 fpstate[3] == 0xe5)) 380 goto out; 381 } else 382 goto out; 383 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, 384 sizeof(fpregs))) 385 goto out; 386 387 if (CPU_IS_COLDFIRE) { 388 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t" 389 "fmovel %1,%%fpcr\n\t" 390 "fmovel %2,%%fpsr\n\t" 391 "fmovel %3,%%fpiar" 392 : /* no outputs */ 393 : "m" (fpregs.f_fpregs[0]), 394 "m" (fpregs.f_fpcntl[0]), 395 "m" (fpregs.f_fpcntl[1]), 396 "m" (fpregs.f_fpcntl[2])); 397 } else { 398 __asm__ volatile (".chip 68k/68881\n\t" 399 "fmovemx %0,%%fp0-%%fp7\n\t" 400 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 401 ".chip 68k" 402 : /* no outputs */ 403 : "m" (*fpregs.f_fpregs), 404 "m" (*fpregs.f_fpcntl)); 405 } 406 } 407 if (context_size && 408 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1, 409 context_size)) 410 goto out; 411 412 if (CPU_IS_COLDFIRE) { 413 __asm__ volatile ("frestore %0" : : "m" (*fpstate)); 414 } else { 415 __asm__ volatile (".chip 68k/68881\n\t" 416 "frestore %0\n\t" 417 ".chip 68k" 418 : : "m" (*fpstate)); 419 } 420 err = 0; 421 422 out: 423 return err; 424 } 425 426 /* 427 * Set up a signal frame. 428 */ 429 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 430 { 431 if (FPU_IS_EMU) { 432 /* save registers */ 433 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); 434 memcpy(sc->sc_fpregs, current->thread.fp, 24); 435 return; 436 } 437 438 if (CPU_IS_COLDFIRE) { 439 __asm__ volatile ("fsave %0" 440 : : "m" (*sc->sc_fpstate) : "memory"); 441 } else { 442 __asm__ volatile (".chip 68k/68881\n\t" 443 "fsave %0\n\t" 444 ".chip 68k" 445 : : "m" (*sc->sc_fpstate) : "memory"); 446 } 447 448 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 449 fpu_version = sc->sc_fpstate[0]; 450 if (CPU_IS_020_OR_030 && 451 regs->vector >= (VEC_FPBRUC * 4) && 452 regs->vector <= (VEC_FPNAN * 4)) { 453 /* Clear pending exception in 68882 idle frame */ 454 if (*(unsigned short *) sc->sc_fpstate == 0x1f38) 455 sc->sc_fpstate[0x38] |= 1 << 3; 456 } 457 458 if (CPU_IS_COLDFIRE) { 459 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t" 460 "fmovel %%fpcr,%1\n\t" 461 "fmovel %%fpsr,%2\n\t" 462 "fmovel %%fpiar,%3" 463 : "=m" (sc->sc_fpregs[0]), 464 "=m" (sc->sc_fpcntl[0]), 465 "=m" (sc->sc_fpcntl[1]), 466 "=m" (sc->sc_fpcntl[2]) 467 : /* no inputs */ 468 : "memory"); 469 } else { 470 __asm__ volatile (".chip 68k/68881\n\t" 471 "fmovemx %%fp0-%%fp1,%0\n\t" 472 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 473 ".chip 68k" 474 : "=m" (*sc->sc_fpregs), 475 "=m" (*sc->sc_fpcntl) 476 : /* no inputs */ 477 : "memory"); 478 } 479 } 480 } 481 482 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 483 { 484 unsigned char fpstate[FPCONTEXT_SIZE]; 485 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 486 int err = 0; 487 488 if (FPU_IS_EMU) { 489 /* save fpu control register */ 490 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, 491 current->thread.fpcntl, 12); 492 /* save all other fpu register */ 493 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, 494 current->thread.fp, 96); 495 return err; 496 } 497 498 if (CPU_IS_COLDFIRE) { 499 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory"); 500 } else { 501 __asm__ volatile (".chip 68k/68881\n\t" 502 "fsave %0\n\t" 503 ".chip 68k" 504 : : "m" (*fpstate) : "memory"); 505 } 506 507 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate); 508 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 509 fpregset_t fpregs; 510 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 511 context_size = fpstate[1]; 512 fpu_version = fpstate[0]; 513 if (CPU_IS_020_OR_030 && 514 regs->vector >= (VEC_FPBRUC * 4) && 515 regs->vector <= (VEC_FPNAN * 4)) { 516 /* Clear pending exception in 68882 idle frame */ 517 if (*(unsigned short *) fpstate == 0x1f38) 518 fpstate[0x38] |= 1 << 3; 519 } 520 if (CPU_IS_COLDFIRE) { 521 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t" 522 "fmovel %%fpcr,%1\n\t" 523 "fmovel %%fpsr,%2\n\t" 524 "fmovel %%fpiar,%3" 525 : "=m" (fpregs.f_fpregs[0]), 526 "=m" (fpregs.f_fpcntl[0]), 527 "=m" (fpregs.f_fpcntl[1]), 528 "=m" (fpregs.f_fpcntl[2]) 529 : /* no inputs */ 530 : "memory"); 531 } else { 532 __asm__ volatile (".chip 68k/68881\n\t" 533 "fmovemx %%fp0-%%fp7,%0\n\t" 534 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 535 ".chip 68k" 536 : "=m" (*fpregs.f_fpregs), 537 "=m" (*fpregs.f_fpcntl) 538 : /* no inputs */ 539 : "memory"); 540 } 541 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, 542 sizeof(fpregs)); 543 } 544 if (context_size) 545 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4, 546 context_size); 547 return err; 548 } 549 550 #else /* CONFIG_FPU */ 551 552 /* 553 * For the case with no FPU configured these all do nothing. 554 */ 555 static inline int restore_fpu_state(struct sigcontext *sc) 556 { 557 return 0; 558 } 559 560 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 561 { 562 return 0; 563 } 564 565 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 566 { 567 } 568 569 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 570 { 571 return 0; 572 } 573 574 #endif /* CONFIG_FPU */ 575 576 static inline void siginfo_build_tests(void) 577 { 578 /* 579 * This needs to be tested on m68k as it has a lesser 580 * alignment requirement than x86 and that can cause surprises. 581 */ 582 583 /* This is part of the ABI and can never change in size: */ 584 BUILD_BUG_ON(sizeof(siginfo_t) != 128); 585 586 /* Ensure the known fields never change in location */ 587 BUILD_BUG_ON(offsetof(siginfo_t, si_signo) != 0); 588 BUILD_BUG_ON(offsetof(siginfo_t, si_errno) != 4); 589 BUILD_BUG_ON(offsetof(siginfo_t, si_code) != 8); 590 591 /* _kill */ 592 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); 593 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); 594 595 /* _timer */ 596 BUILD_BUG_ON(offsetof(siginfo_t, si_tid) != 0x0c); 597 BUILD_BUG_ON(offsetof(siginfo_t, si_overrun) != 0x10); 598 BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x14); 599 600 /* _rt */ 601 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); 602 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); 603 BUILD_BUG_ON(offsetof(siginfo_t, si_value) != 0x14); 604 605 /* _sigchld */ 606 BUILD_BUG_ON(offsetof(siginfo_t, si_pid) != 0x0c); 607 BUILD_BUG_ON(offsetof(siginfo_t, si_uid) != 0x10); 608 BUILD_BUG_ON(offsetof(siginfo_t, si_status) != 0x14); 609 BUILD_BUG_ON(offsetof(siginfo_t, si_utime) != 0x18); 610 BUILD_BUG_ON(offsetof(siginfo_t, si_stime) != 0x1c); 611 612 /* _sigfault */ 613 BUILD_BUG_ON(offsetof(siginfo_t, si_addr) != 0x0c); 614 615 /* _sigfault._mcerr */ 616 BUILD_BUG_ON(offsetof(siginfo_t, si_addr_lsb) != 0x10); 617 618 /* _sigfault._addr_bnd */ 619 BUILD_BUG_ON(offsetof(siginfo_t, si_lower) != 0x12); 620 BUILD_BUG_ON(offsetof(siginfo_t, si_upper) != 0x16); 621 622 /* _sigfault._addr_pkey */ 623 BUILD_BUG_ON(offsetof(siginfo_t, si_pkey) != 0x12); 624 625 /* _sigpoll */ 626 BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x0c); 627 BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x10); 628 629 /* _sigsys */ 630 BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x0c); 631 BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x10); 632 BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x14); 633 634 /* any new si_fields should be added here */ 635 } 636 637 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, 638 void __user *fp) 639 { 640 int fsize = frame_extra_sizes(formatvec >> 12); 641 if (fsize < 0) { 642 /* 643 * user process trying to return with weird frame format 644 */ 645 pr_debug("user process returning with weird frame format\n"); 646 return 1; 647 } 648 if (!fsize) { 649 regs->format = formatvec >> 12; 650 regs->vector = formatvec & 0xfff; 651 } else { 652 struct switch_stack *sw = (struct switch_stack *)regs - 1; 653 /* yes, twice as much as max(sizeof(frame.un.fmt<x>)) */ 654 unsigned long buf[sizeof_field(struct frame, un) / 2]; 655 656 /* that'll make sure that expansion won't crap over data */ 657 if (copy_from_user(buf + fsize / 4, fp, fsize)) 658 return 1; 659 660 /* point of no return */ 661 regs->format = formatvec >> 12; 662 regs->vector = formatvec & 0xfff; 663 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) 664 __asm__ __volatile__ ( 665 #ifdef CONFIG_COLDFIRE 666 " movel %0,%/sp\n\t" 667 " bra ret_from_signal\n" 668 #else 669 " movel %0,%/a0\n\t" 670 " subl %1,%/a0\n\t" /* make room on stack */ 671 " movel %/a0,%/sp\n\t" /* set stack pointer */ 672 /* move switch_stack and pt_regs */ 673 "1: movel %0@+,%/a0@+\n\t" 674 " dbra %2,1b\n\t" 675 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ 676 " lsrl #2,%1\n\t" 677 " subql #1,%1\n\t" 678 /* copy to the gap we'd made */ 679 "2: movel %4@+,%/a0@+\n\t" 680 " dbra %1,2b\n\t" 681 " bral ret_from_signal\n" 682 #endif 683 : /* no outputs, it doesn't ever return */ 684 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), 685 "n" (frame_offset), "a" (buf + fsize/4) 686 : "a0"); 687 #undef frame_offset 688 } 689 return 0; 690 } 691 692 static inline int 693 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) 694 { 695 int formatvec; 696 struct sigcontext context; 697 int err = 0; 698 699 siginfo_build_tests(); 700 701 /* Always make any pending restarted system calls return -EINTR */ 702 current->restart_block.fn = do_no_restart_syscall; 703 704 /* get previous context */ 705 if (copy_from_user(&context, usc, sizeof(context))) 706 goto badframe; 707 708 /* restore passed registers */ 709 regs->d0 = context.sc_d0; 710 regs->d1 = context.sc_d1; 711 regs->a0 = context.sc_a0; 712 regs->a1 = context.sc_a1; 713 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); 714 regs->pc = context.sc_pc; 715 regs->orig_d0 = -1; /* disable syscall checks */ 716 wrusp(context.sc_usp); 717 formatvec = context.sc_formatvec; 718 719 err = restore_fpu_state(&context); 720 721 if (err || mangle_kernel_stack(regs, formatvec, fp)) 722 goto badframe; 723 724 return 0; 725 726 badframe: 727 return 1; 728 } 729 730 static inline int 731 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, 732 struct ucontext __user *uc) 733 { 734 int temp; 735 greg_t __user *gregs = uc->uc_mcontext.gregs; 736 unsigned long usp; 737 int err; 738 739 /* Always make any pending restarted system calls return -EINTR */ 740 current->restart_block.fn = do_no_restart_syscall; 741 742 err = __get_user(temp, &uc->uc_mcontext.version); 743 if (temp != MCONTEXT_VERSION) 744 goto badframe; 745 /* restore passed registers */ 746 err |= __get_user(regs->d0, &gregs[0]); 747 err |= __get_user(regs->d1, &gregs[1]); 748 err |= __get_user(regs->d2, &gregs[2]); 749 err |= __get_user(regs->d3, &gregs[3]); 750 err |= __get_user(regs->d4, &gregs[4]); 751 err |= __get_user(regs->d5, &gregs[5]); 752 err |= __get_user(sw->d6, &gregs[6]); 753 err |= __get_user(sw->d7, &gregs[7]); 754 err |= __get_user(regs->a0, &gregs[8]); 755 err |= __get_user(regs->a1, &gregs[9]); 756 err |= __get_user(regs->a2, &gregs[10]); 757 err |= __get_user(sw->a3, &gregs[11]); 758 err |= __get_user(sw->a4, &gregs[12]); 759 err |= __get_user(sw->a5, &gregs[13]); 760 err |= __get_user(sw->a6, &gregs[14]); 761 err |= __get_user(usp, &gregs[15]); 762 wrusp(usp); 763 err |= __get_user(regs->pc, &gregs[16]); 764 err |= __get_user(temp, &gregs[17]); 765 regs->sr = (regs->sr & 0xff00) | (temp & 0xff); 766 regs->orig_d0 = -1; /* disable syscall checks */ 767 err |= __get_user(temp, &uc->uc_formatvec); 768 769 err |= rt_restore_fpu_state(uc); 770 err |= restore_altstack(&uc->uc_stack); 771 772 if (err) 773 goto badframe; 774 775 if (mangle_kernel_stack(regs, temp, &uc->uc_extra)) 776 goto badframe; 777 778 return 0; 779 780 badframe: 781 return 1; 782 } 783 784 asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 785 { 786 unsigned long usp = rdusp(); 787 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 788 sigset_t set; 789 790 if (!access_ok(frame, sizeof(*frame))) 791 goto badframe; 792 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 793 (_NSIG_WORDS > 1 && 794 __copy_from_user(&set.sig[1], &frame->extramask, 795 sizeof(frame->extramask)))) 796 goto badframe; 797 798 set_current_blocked(&set); 799 800 if (restore_sigcontext(regs, &frame->sc, frame + 1)) 801 goto badframe; 802 return regs->d0; 803 804 badframe: 805 force_sig(SIGSEGV); 806 return 0; 807 } 808 809 asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 810 { 811 unsigned long usp = rdusp(); 812 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 813 sigset_t set; 814 815 if (!access_ok(frame, sizeof(*frame))) 816 goto badframe; 817 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 818 goto badframe; 819 820 set_current_blocked(&set); 821 822 if (rt_restore_ucontext(regs, sw, &frame->uc)) 823 goto badframe; 824 return regs->d0; 825 826 badframe: 827 force_sig(SIGSEGV); 828 return 0; 829 } 830 831 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 832 unsigned long mask) 833 { 834 sc->sc_mask = mask; 835 sc->sc_usp = rdusp(); 836 sc->sc_d0 = regs->d0; 837 sc->sc_d1 = regs->d1; 838 sc->sc_a0 = regs->a0; 839 sc->sc_a1 = regs->a1; 840 sc->sc_sr = regs->sr; 841 sc->sc_pc = regs->pc; 842 sc->sc_formatvec = regs->format << 12 | regs->vector; 843 save_a5_state(sc, regs); 844 save_fpu_state(sc, regs); 845 } 846 847 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 848 { 849 struct switch_stack *sw = (struct switch_stack *)regs - 1; 850 greg_t __user *gregs = uc->uc_mcontext.gregs; 851 int err = 0; 852 853 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 854 err |= __put_user(regs->d0, &gregs[0]); 855 err |= __put_user(regs->d1, &gregs[1]); 856 err |= __put_user(regs->d2, &gregs[2]); 857 err |= __put_user(regs->d3, &gregs[3]); 858 err |= __put_user(regs->d4, &gregs[4]); 859 err |= __put_user(regs->d5, &gregs[5]); 860 err |= __put_user(sw->d6, &gregs[6]); 861 err |= __put_user(sw->d7, &gregs[7]); 862 err |= __put_user(regs->a0, &gregs[8]); 863 err |= __put_user(regs->a1, &gregs[9]); 864 err |= __put_user(regs->a2, &gregs[10]); 865 err |= __put_user(sw->a3, &gregs[11]); 866 err |= __put_user(sw->a4, &gregs[12]); 867 err |= __put_user(sw->a5, &gregs[13]); 868 err |= __put_user(sw->a6, &gregs[14]); 869 err |= __put_user(rdusp(), &gregs[15]); 870 err |= __put_user(regs->pc, &gregs[16]); 871 err |= __put_user(regs->sr, &gregs[17]); 872 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); 873 err |= rt_save_fpu_state(uc, regs); 874 return err; 875 } 876 877 static inline void __user * 878 get_sigframe(struct ksignal *ksig, size_t frame_size) 879 { 880 unsigned long usp = sigsp(rdusp(), ksig); 881 882 return (void __user *)((usp - frame_size) & -8UL); 883 } 884 885 static int setup_frame(struct ksignal *ksig, sigset_t *set, 886 struct pt_regs *regs) 887 { 888 struct sigframe __user *frame; 889 int fsize = frame_extra_sizes(regs->format); 890 struct sigcontext context; 891 int err = 0, sig = ksig->sig; 892 893 if (fsize < 0) { 894 pr_debug("setup_frame: Unknown frame format %#x\n", 895 regs->format); 896 return -EFAULT; 897 } 898 899 frame = get_sigframe(ksig, sizeof(*frame) + fsize); 900 901 if (fsize) 902 err |= copy_to_user (frame + 1, regs + 1, fsize); 903 904 err |= __put_user(sig, &frame->sig); 905 906 err |= __put_user(regs->vector, &frame->code); 907 err |= __put_user(&frame->sc, &frame->psc); 908 909 if (_NSIG_WORDS > 1) 910 err |= copy_to_user(frame->extramask, &set->sig[1], 911 sizeof(frame->extramask)); 912 913 setup_sigcontext(&context, regs, set->sig[0]); 914 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 915 916 /* Set up to return from userspace. */ 917 #ifdef CONFIG_MMU 918 err |= __put_user(frame->retcode, &frame->pretcode); 919 /* moveq #,d0; trap #0 */ 920 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 921 (long __user *)(frame->retcode)); 922 #else 923 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode); 924 #endif 925 926 if (err) 927 return -EFAULT; 928 929 push_cache ((unsigned long) &frame->retcode); 930 931 /* 932 * Set up registers for signal handler. All the state we are about 933 * to destroy is successfully copied to sigframe. 934 */ 935 wrusp ((unsigned long) frame); 936 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 937 adjustformat(regs); 938 939 /* 940 * This is subtle; if we build more than one sigframe, all but the 941 * first one will see frame format 0 and have fsize == 0, so we won't 942 * screw stkadj. 943 */ 944 if (fsize) 945 regs->stkadj = fsize; 946 947 /* Prepare to skip over the extra stuff in the exception frame. */ 948 if (regs->stkadj) { 949 struct pt_regs *tregs = 950 (struct pt_regs *)((ulong)regs + regs->stkadj); 951 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 952 /* This must be copied with decreasing addresses to 953 handle overlaps. */ 954 tregs->vector = 0; 955 tregs->format = 0; 956 tregs->pc = regs->pc; 957 tregs->sr = regs->sr; 958 } 959 return 0; 960 } 961 962 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, 963 struct pt_regs *regs) 964 { 965 struct rt_sigframe __user *frame; 966 int fsize = frame_extra_sizes(regs->format); 967 int err = 0, sig = ksig->sig; 968 969 if (fsize < 0) { 970 pr_debug("setup_frame: Unknown frame format %#x\n", 971 regs->format); 972 return -EFAULT; 973 } 974 975 frame = get_sigframe(ksig, sizeof(*frame)); 976 977 if (fsize) 978 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 979 980 err |= __put_user(sig, &frame->sig); 981 err |= __put_user(&frame->info, &frame->pinfo); 982 err |= __put_user(&frame->uc, &frame->puc); 983 err |= copy_siginfo_to_user(&frame->info, &ksig->info); 984 985 /* Create the ucontext. */ 986 err |= __put_user(0, &frame->uc.uc_flags); 987 err |= __put_user(NULL, &frame->uc.uc_link); 988 err |= __save_altstack(&frame->uc.uc_stack, rdusp()); 989 err |= rt_setup_ucontext(&frame->uc, regs); 990 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 991 992 /* Set up to return from userspace. */ 993 #ifdef CONFIG_MMU 994 err |= __put_user(frame->retcode, &frame->pretcode); 995 #ifdef __mcoldfire__ 996 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 997 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 998 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 999 (long __user *)(frame->retcode + 4)); 1000 #else 1001 /* moveq #,d0; notb d0; trap #0 */ 1002 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 1003 (long __user *)(frame->retcode + 0)); 1004 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 1005 #endif 1006 #else 1007 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode); 1008 #endif /* CONFIG_MMU */ 1009 1010 if (err) 1011 return -EFAULT; 1012 1013 push_cache ((unsigned long) &frame->retcode); 1014 1015 /* 1016 * Set up registers for signal handler. All the state we are about 1017 * to destroy is successfully copied to sigframe. 1018 */ 1019 wrusp ((unsigned long) frame); 1020 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 1021 adjustformat(regs); 1022 1023 /* 1024 * This is subtle; if we build more than one sigframe, all but the 1025 * first one will see frame format 0 and have fsize == 0, so we won't 1026 * screw stkadj. 1027 */ 1028 if (fsize) 1029 regs->stkadj = fsize; 1030 1031 /* Prepare to skip over the extra stuff in the exception frame. */ 1032 if (regs->stkadj) { 1033 struct pt_regs *tregs = 1034 (struct pt_regs *)((ulong)regs + regs->stkadj); 1035 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 1036 /* This must be copied with decreasing addresses to 1037 handle overlaps. */ 1038 tregs->vector = 0; 1039 tregs->format = 0; 1040 tregs->pc = regs->pc; 1041 tregs->sr = regs->sr; 1042 } 1043 return 0; 1044 } 1045 1046 static inline void 1047 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1048 { 1049 switch (regs->d0) { 1050 case -ERESTARTNOHAND: 1051 if (!has_handler) 1052 goto do_restart; 1053 regs->d0 = -EINTR; 1054 break; 1055 1056 case -ERESTART_RESTARTBLOCK: 1057 if (!has_handler) { 1058 regs->d0 = __NR_restart_syscall; 1059 regs->pc -= 2; 1060 break; 1061 } 1062 regs->d0 = -EINTR; 1063 break; 1064 1065 case -ERESTARTSYS: 1066 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1067 regs->d0 = -EINTR; 1068 break; 1069 } 1070 fallthrough; 1071 case -ERESTARTNOINTR: 1072 do_restart: 1073 regs->d0 = regs->orig_d0; 1074 regs->pc -= 2; 1075 break; 1076 } 1077 } 1078 1079 /* 1080 * OK, we're invoking a handler 1081 */ 1082 static void 1083 handle_signal(struct ksignal *ksig, struct pt_regs *regs) 1084 { 1085 sigset_t *oldset = sigmask_to_save(); 1086 int err; 1087 /* are we from a system call? */ 1088 if (regs->orig_d0 >= 0) 1089 /* If so, check system call restarting.. */ 1090 handle_restart(regs, &ksig->ka, 1); 1091 1092 /* set up the stack frame */ 1093 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 1094 err = setup_rt_frame(ksig, oldset, regs); 1095 else 1096 err = setup_frame(ksig, oldset, regs); 1097 1098 signal_setup_done(err, ksig, 0); 1099 1100 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1101 regs->sr &= ~0x8000; 1102 send_sig(SIGTRAP, current, 1); 1103 } 1104 } 1105 1106 /* 1107 * Note that 'init' is a special process: it doesn't get signals it doesn't 1108 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1109 * mistake. 1110 */ 1111 static void do_signal(struct pt_regs *regs) 1112 { 1113 struct ksignal ksig; 1114 1115 current->thread.esp0 = (unsigned long) regs; 1116 1117 if (get_signal(&ksig)) { 1118 /* Whee! Actually deliver the signal. */ 1119 handle_signal(&ksig, regs); 1120 return; 1121 } 1122 1123 /* Did we come from a system call? */ 1124 if (regs->orig_d0 >= 0) 1125 /* Restart the system call - no handlers present */ 1126 handle_restart(regs, NULL, 0); 1127 1128 /* If there's no signal to deliver, we just restore the saved mask. */ 1129 restore_saved_sigmask(); 1130 } 1131 1132 void do_notify_resume(struct pt_regs *regs) 1133 { 1134 if (test_thread_flag(TIF_SIGPENDING)) 1135 do_signal(regs); 1136 1137 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) 1138 tracehook_notify_resume(regs); 1139 } 1140