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/resume_user_mode.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 && !regs->stkadj && 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 && !regs->stkadj && 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 /* _sigfault._perf */ 626 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_data) != 0x10); 627 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_type) != 0x14); 628 BUILD_BUG_ON(offsetof(siginfo_t, si_perf_flags) != 0x18); 629 630 /* _sigpoll */ 631 BUILD_BUG_ON(offsetof(siginfo_t, si_band) != 0x0c); 632 BUILD_BUG_ON(offsetof(siginfo_t, si_fd) != 0x10); 633 634 /* _sigsys */ 635 BUILD_BUG_ON(offsetof(siginfo_t, si_call_addr) != 0x0c); 636 BUILD_BUG_ON(offsetof(siginfo_t, si_syscall) != 0x10); 637 BUILD_BUG_ON(offsetof(siginfo_t, si_arch) != 0x14); 638 639 /* any new si_fields should be added here */ 640 } 641 642 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, 643 void __user *fp) 644 { 645 int extra = frame_extra_sizes(formatvec >> 12); 646 char buf[sizeof_field(struct frame, un)]; 647 648 if (extra < 0) { 649 /* 650 * user process trying to return with weird frame format 651 */ 652 pr_debug("user process returning with weird frame format\n"); 653 return -1; 654 } 655 if (extra && copy_from_user(buf, fp, extra)) 656 return -1; 657 regs->format = formatvec >> 12; 658 regs->vector = formatvec & 0xfff; 659 if (extra) { 660 void *p = (struct switch_stack *)regs - 1; 661 struct frame *new = (void *)regs - extra; 662 int size = sizeof(struct pt_regs)+sizeof(struct switch_stack); 663 664 memmove(p - extra, p, size); 665 memcpy(p - extra + size, buf, extra); 666 current->thread.esp0 = (unsigned long)&new->ptregs; 667 #ifdef CONFIG_M68040 668 /* on 68040 complete pending writebacks if any */ 669 if (new->ptregs.format == 7) // bus error frame 670 berr_040cleanup(new); 671 #endif 672 } 673 return extra; 674 } 675 676 static inline int 677 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) 678 { 679 int formatvec; 680 struct sigcontext context; 681 682 siginfo_build_tests(); 683 684 /* Always make any pending restarted system calls return -EINTR */ 685 current->restart_block.fn = do_no_restart_syscall; 686 687 /* get previous context */ 688 if (copy_from_user(&context, usc, sizeof(context))) 689 return -1; 690 691 /* restore passed registers */ 692 regs->d0 = context.sc_d0; 693 regs->d1 = context.sc_d1; 694 regs->a0 = context.sc_a0; 695 regs->a1 = context.sc_a1; 696 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); 697 regs->pc = context.sc_pc; 698 regs->orig_d0 = -1; /* disable syscall checks */ 699 wrusp(context.sc_usp); 700 formatvec = context.sc_formatvec; 701 702 if (restore_fpu_state(&context)) 703 return -1; 704 705 return mangle_kernel_stack(regs, formatvec, fp); 706 } 707 708 static inline int 709 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, 710 struct ucontext __user *uc) 711 { 712 int temp; 713 greg_t __user *gregs = uc->uc_mcontext.gregs; 714 unsigned long usp; 715 int err; 716 717 /* Always make any pending restarted system calls return -EINTR */ 718 current->restart_block.fn = do_no_restart_syscall; 719 720 err = __get_user(temp, &uc->uc_mcontext.version); 721 if (temp != MCONTEXT_VERSION) 722 return -1; 723 /* restore passed registers */ 724 err |= __get_user(regs->d0, &gregs[0]); 725 err |= __get_user(regs->d1, &gregs[1]); 726 err |= __get_user(regs->d2, &gregs[2]); 727 err |= __get_user(regs->d3, &gregs[3]); 728 err |= __get_user(regs->d4, &gregs[4]); 729 err |= __get_user(regs->d5, &gregs[5]); 730 err |= __get_user(sw->d6, &gregs[6]); 731 err |= __get_user(sw->d7, &gregs[7]); 732 err |= __get_user(regs->a0, &gregs[8]); 733 err |= __get_user(regs->a1, &gregs[9]); 734 err |= __get_user(regs->a2, &gregs[10]); 735 err |= __get_user(sw->a3, &gregs[11]); 736 err |= __get_user(sw->a4, &gregs[12]); 737 err |= __get_user(sw->a5, &gregs[13]); 738 err |= __get_user(sw->a6, &gregs[14]); 739 err |= __get_user(usp, &gregs[15]); 740 wrusp(usp); 741 err |= __get_user(regs->pc, &gregs[16]); 742 err |= __get_user(temp, &gregs[17]); 743 regs->sr = (regs->sr & 0xff00) | (temp & 0xff); 744 regs->orig_d0 = -1; /* disable syscall checks */ 745 err |= __get_user(temp, &uc->uc_formatvec); 746 747 err |= rt_restore_fpu_state(uc); 748 err |= restore_altstack(&uc->uc_stack); 749 750 if (err) 751 return -1; 752 753 return mangle_kernel_stack(regs, temp, &uc->uc_extra); 754 } 755 756 asmlinkage void *do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 757 { 758 unsigned long usp = rdusp(); 759 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 760 sigset_t set; 761 int size; 762 763 if (!access_ok(frame, sizeof(*frame))) 764 goto badframe; 765 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 766 (_NSIG_WORDS > 1 && 767 __copy_from_user(&set.sig[1], &frame->extramask, 768 sizeof(frame->extramask)))) 769 goto badframe; 770 771 set_current_blocked(&set); 772 773 size = restore_sigcontext(regs, &frame->sc, frame + 1); 774 if (size < 0) 775 goto badframe; 776 return (void *)sw - size; 777 778 badframe: 779 force_sig(SIGSEGV); 780 return sw; 781 } 782 783 asmlinkage void *do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 784 { 785 unsigned long usp = rdusp(); 786 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 787 sigset_t set; 788 int size; 789 790 if (!access_ok(frame, sizeof(*frame))) 791 goto badframe; 792 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 793 goto badframe; 794 795 set_current_blocked(&set); 796 797 size = rt_restore_ucontext(regs, sw, &frame->uc); 798 if (size < 0) 799 goto badframe; 800 return (void *)sw - size; 801 802 badframe: 803 force_sig(SIGSEGV); 804 return sw; 805 } 806 807 static inline struct pt_regs *rte_regs(struct pt_regs *regs) 808 { 809 return (void *)regs + regs->stkadj; 810 } 811 812 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 813 unsigned long mask) 814 { 815 struct pt_regs *tregs = rte_regs(regs); 816 sc->sc_mask = mask; 817 sc->sc_usp = rdusp(); 818 sc->sc_d0 = regs->d0; 819 sc->sc_d1 = regs->d1; 820 sc->sc_a0 = regs->a0; 821 sc->sc_a1 = regs->a1; 822 sc->sc_sr = tregs->sr; 823 sc->sc_pc = tregs->pc; 824 sc->sc_formatvec = tregs->format << 12 | tregs->vector; 825 save_a5_state(sc, regs); 826 save_fpu_state(sc, regs); 827 } 828 829 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 830 { 831 struct switch_stack *sw = (struct switch_stack *)regs - 1; 832 struct pt_regs *tregs = rte_regs(regs); 833 greg_t __user *gregs = uc->uc_mcontext.gregs; 834 int err = 0; 835 836 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 837 err |= __put_user(regs->d0, &gregs[0]); 838 err |= __put_user(regs->d1, &gregs[1]); 839 err |= __put_user(regs->d2, &gregs[2]); 840 err |= __put_user(regs->d3, &gregs[3]); 841 err |= __put_user(regs->d4, &gregs[4]); 842 err |= __put_user(regs->d5, &gregs[5]); 843 err |= __put_user(sw->d6, &gregs[6]); 844 err |= __put_user(sw->d7, &gregs[7]); 845 err |= __put_user(regs->a0, &gregs[8]); 846 err |= __put_user(regs->a1, &gregs[9]); 847 err |= __put_user(regs->a2, &gregs[10]); 848 err |= __put_user(sw->a3, &gregs[11]); 849 err |= __put_user(sw->a4, &gregs[12]); 850 err |= __put_user(sw->a5, &gregs[13]); 851 err |= __put_user(sw->a6, &gregs[14]); 852 err |= __put_user(rdusp(), &gregs[15]); 853 err |= __put_user(tregs->pc, &gregs[16]); 854 err |= __put_user(tregs->sr, &gregs[17]); 855 err |= __put_user((tregs->format << 12) | tregs->vector, &uc->uc_formatvec); 856 err |= rt_save_fpu_state(uc, regs); 857 return err; 858 } 859 860 static inline void __user * 861 get_sigframe(struct ksignal *ksig, struct pt_regs *tregs, size_t frame_size) 862 { 863 unsigned long usp = sigsp(rdusp(), ksig); 864 unsigned long gap = 0; 865 866 if (CPU_IS_020_OR_030 && tregs->format == 0xb) { 867 /* USP is unreliable so use worst-case value */ 868 gap = 256; 869 } 870 871 return (void __user *)((usp - gap - frame_size) & -8UL); 872 } 873 874 static int setup_frame(struct ksignal *ksig, sigset_t *set, 875 struct pt_regs *regs) 876 { 877 struct sigframe __user *frame; 878 struct pt_regs *tregs = rte_regs(regs); 879 int fsize = frame_extra_sizes(tregs->format); 880 struct sigcontext context; 881 int err = 0, sig = ksig->sig; 882 883 if (fsize < 0) { 884 pr_debug("setup_frame: Unknown frame format %#x\n", 885 tregs->format); 886 return -EFAULT; 887 } 888 889 frame = get_sigframe(ksig, tregs, sizeof(*frame) + fsize); 890 891 if (fsize) 892 err |= copy_to_user (frame + 1, regs + 1, fsize); 893 894 err |= __put_user(sig, &frame->sig); 895 896 err |= __put_user(tregs->vector, &frame->code); 897 err |= __put_user(&frame->sc, &frame->psc); 898 899 if (_NSIG_WORDS > 1) 900 err |= copy_to_user(frame->extramask, &set->sig[1], 901 sizeof(frame->extramask)); 902 903 setup_sigcontext(&context, regs, set->sig[0]); 904 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 905 906 /* Set up to return from userspace. */ 907 #ifdef CONFIG_MMU 908 err |= __put_user(frame->retcode, &frame->pretcode); 909 /* moveq #,d0; trap #0 */ 910 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 911 (long __user *)(frame->retcode)); 912 #else 913 err |= __put_user((long) ret_from_user_signal, 914 (long __user *) &frame->pretcode); 915 #endif 916 917 if (err) 918 return -EFAULT; 919 920 push_cache ((unsigned long) &frame->retcode); 921 922 /* 923 * This is subtle; if we build more than one sigframe, all but the 924 * first one will see frame format 0 and have fsize == 0, so we won't 925 * screw stkadj. 926 */ 927 if (fsize) { 928 regs->stkadj = fsize; 929 tregs = rte_regs(regs); 930 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 931 tregs->vector = 0; 932 tregs->format = 0; 933 tregs->sr = regs->sr; 934 } 935 936 /* 937 * Set up registers for signal handler. All the state we are about 938 * to destroy is successfully copied to sigframe. 939 */ 940 wrusp ((unsigned long) frame); 941 tregs->pc = (unsigned long) ksig->ka.sa.sa_handler; 942 adjustformat(regs); 943 944 return 0; 945 } 946 947 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, 948 struct pt_regs *regs) 949 { 950 struct rt_sigframe __user *frame; 951 struct pt_regs *tregs = rte_regs(regs); 952 int fsize = frame_extra_sizes(tregs->format); 953 int err = 0, sig = ksig->sig; 954 955 if (fsize < 0) { 956 pr_debug("setup_frame: Unknown frame format %#x\n", 957 regs->format); 958 return -EFAULT; 959 } 960 961 frame = get_sigframe(ksig, tregs, sizeof(*frame)); 962 963 if (fsize) 964 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 965 966 err |= __put_user(sig, &frame->sig); 967 err |= __put_user(&frame->info, &frame->pinfo); 968 err |= __put_user(&frame->uc, &frame->puc); 969 err |= copy_siginfo_to_user(&frame->info, &ksig->info); 970 971 /* Create the ucontext. */ 972 err |= __put_user(0, &frame->uc.uc_flags); 973 err |= __put_user(NULL, &frame->uc.uc_link); 974 err |= __save_altstack(&frame->uc.uc_stack, rdusp()); 975 err |= rt_setup_ucontext(&frame->uc, regs); 976 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 977 978 /* Set up to return from userspace. */ 979 #ifdef CONFIG_MMU 980 err |= __put_user(frame->retcode, &frame->pretcode); 981 #ifdef __mcoldfire__ 982 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 983 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 984 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 985 (long __user *)(frame->retcode + 4)); 986 #else 987 /* moveq #,d0; notb d0; trap #0 */ 988 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 989 (long __user *)(frame->retcode + 0)); 990 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 991 #endif 992 #else 993 err |= __put_user((long) ret_from_user_rt_signal, 994 (long __user *) &frame->pretcode); 995 #endif /* CONFIG_MMU */ 996 997 if (err) 998 return -EFAULT; 999 1000 push_cache ((unsigned long) &frame->retcode); 1001 1002 /* 1003 * This is subtle; if we build more than one sigframe, all but the 1004 * first one will see frame format 0 and have fsize == 0, so we won't 1005 * screw stkadj. 1006 */ 1007 if (fsize) { 1008 regs->stkadj = fsize; 1009 tregs = rte_regs(regs); 1010 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 1011 tregs->vector = 0; 1012 tregs->format = 0; 1013 tregs->sr = regs->sr; 1014 } 1015 1016 /* 1017 * Set up registers for signal handler. All the state we are about 1018 * to destroy is successfully copied to sigframe. 1019 */ 1020 wrusp ((unsigned long) frame); 1021 tregs->pc = (unsigned long) ksig->ka.sa.sa_handler; 1022 adjustformat(regs); 1023 return 0; 1024 } 1025 1026 static inline void 1027 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1028 { 1029 switch (regs->d0) { 1030 case -ERESTARTNOHAND: 1031 if (!has_handler) 1032 goto do_restart; 1033 regs->d0 = -EINTR; 1034 break; 1035 1036 case -ERESTART_RESTARTBLOCK: 1037 if (!has_handler) { 1038 regs->d0 = __NR_restart_syscall; 1039 regs->pc -= 2; 1040 break; 1041 } 1042 regs->d0 = -EINTR; 1043 break; 1044 1045 case -ERESTARTSYS: 1046 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1047 regs->d0 = -EINTR; 1048 break; 1049 } 1050 fallthrough; 1051 case -ERESTARTNOINTR: 1052 do_restart: 1053 regs->d0 = regs->orig_d0; 1054 regs->pc -= 2; 1055 break; 1056 } 1057 } 1058 1059 /* 1060 * OK, we're invoking a handler 1061 */ 1062 static void 1063 handle_signal(struct ksignal *ksig, struct pt_regs *regs) 1064 { 1065 sigset_t *oldset = sigmask_to_save(); 1066 int err; 1067 /* are we from a system call? */ 1068 if (regs->orig_d0 >= 0) 1069 /* If so, check system call restarting.. */ 1070 handle_restart(regs, &ksig->ka, 1); 1071 1072 /* set up the stack frame */ 1073 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 1074 err = setup_rt_frame(ksig, oldset, regs); 1075 else 1076 err = setup_frame(ksig, oldset, regs); 1077 1078 signal_setup_done(err, ksig, 0); 1079 1080 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1081 regs->sr &= ~0x8000; 1082 send_sig(SIGTRAP, current, 1); 1083 } 1084 } 1085 1086 /* 1087 * Note that 'init' is a special process: it doesn't get signals it doesn't 1088 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1089 * mistake. 1090 */ 1091 static void do_signal(struct pt_regs *regs) 1092 { 1093 struct ksignal ksig; 1094 1095 current->thread.esp0 = (unsigned long) regs; 1096 1097 if (get_signal(&ksig)) { 1098 /* Whee! Actually deliver the signal. */ 1099 handle_signal(&ksig, regs); 1100 return; 1101 } 1102 1103 /* Did we come from a system call? */ 1104 if (regs->orig_d0 >= 0) 1105 /* Restart the system call - no handlers present */ 1106 handle_restart(regs, NULL, 0); 1107 1108 /* If there's no signal to deliver, we just restore the saved mask. */ 1109 restore_saved_sigmask(); 1110 } 1111 1112 void do_notify_resume(struct pt_regs *regs) 1113 { 1114 if (test_thread_flag(TIF_NOTIFY_SIGNAL) || 1115 test_thread_flag(TIF_SIGPENDING)) 1116 do_signal(regs); 1117 1118 if (test_thread_flag(TIF_NOTIFY_RESUME)) 1119 resume_user_mode_work(regs); 1120 } 1121