signal_32.c revision 451a651d33b240481b063765016472c0be10d350
1/* 2 * Signal handling for 32bit PPC and 32bit tasks on 64bit PPC 3 * 4 * PowerPC version 5 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 6 * Copyright (C) 2001 IBM 7 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 8 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu) 9 * 10 * Derived from "arch/i386/kernel/signal.c" 11 * Copyright (C) 1991, 1992 Linus Torvalds 12 * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 */ 19 20#include <linux/sched.h> 21#include <linux/mm.h> 22#include <linux/smp.h> 23#include <linux/kernel.h> 24#include <linux/signal.h> 25#include <linux/errno.h> 26#include <linux/elf.h> 27#include <linux/ptrace.h> 28#include <linux/ratelimit.h> 29#ifdef CONFIG_PPC64 30#include <linux/syscalls.h> 31#include <linux/compat.h> 32#else 33#include <linux/wait.h> 34#include <linux/unistd.h> 35#include <linux/stddef.h> 36#include <linux/tty.h> 37#include <linux/binfmts.h> 38#endif 39 40#include <asm/uaccess.h> 41#include <asm/cacheflush.h> 42#include <asm/syscalls.h> 43#include <asm/sigcontext.h> 44#include <asm/vdso.h> 45#include <asm/switch_to.h> 46#ifdef CONFIG_PPC64 47#include "ppc32.h" 48#include <asm/unistd.h> 49#else 50#include <asm/ucontext.h> 51#include <asm/pgtable.h> 52#endif 53 54#include "signal.h" 55 56#undef DEBUG_SIG 57 58#ifdef CONFIG_PPC64 59#define sys_sigsuspend compat_sys_sigsuspend 60#define sys_rt_sigreturn compat_sys_rt_sigreturn 61#define sys_sigaction compat_sys_sigaction 62#define sys_swapcontext compat_sys_swapcontext 63#define sys_sigreturn compat_sys_sigreturn 64 65#define old_sigaction old_sigaction32 66#define sigcontext sigcontext32 67#define mcontext mcontext32 68#define ucontext ucontext32 69 70#define __save_altstack __compat_save_altstack 71 72/* 73 * Userspace code may pass a ucontext which doesn't include VSX added 74 * at the end. We need to check for this case. 75 */ 76#define UCONTEXTSIZEWITHOUTVSX \ 77 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32)) 78 79/* 80 * Returning 0 means we return to userspace via 81 * ret_from_except and thus restore all user 82 * registers from *regs. This is what we need 83 * to do when a signal has been delivered. 84 */ 85 86#define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32)) 87#undef __SIGNAL_FRAMESIZE 88#define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32 89#undef ELF_NVRREG 90#define ELF_NVRREG ELF_NVRREG32 91 92/* 93 * Functions for flipping sigsets (thanks to brain dead generic 94 * implementation that makes things simple for little endian only) 95 */ 96static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set) 97{ 98 compat_sigset_t cset; 99 100 switch (_NSIG_WORDS) { 101 case 4: cset.sig[6] = set->sig[3] & 0xffffffffull; 102 cset.sig[7] = set->sig[3] >> 32; 103 case 3: cset.sig[4] = set->sig[2] & 0xffffffffull; 104 cset.sig[5] = set->sig[2] >> 32; 105 case 2: cset.sig[2] = set->sig[1] & 0xffffffffull; 106 cset.sig[3] = set->sig[1] >> 32; 107 case 1: cset.sig[0] = set->sig[0] & 0xffffffffull; 108 cset.sig[1] = set->sig[0] >> 32; 109 } 110 return copy_to_user(uset, &cset, sizeof(*uset)); 111} 112 113static inline int get_sigset_t(sigset_t *set, 114 const compat_sigset_t __user *uset) 115{ 116 compat_sigset_t s32; 117 118 if (copy_from_user(&s32, uset, sizeof(*uset))) 119 return -EFAULT; 120 121 /* 122 * Swap the 2 words of the 64-bit sigset_t (they are stored 123 * in the "wrong" endian in 32-bit user storage). 124 */ 125 switch (_NSIG_WORDS) { 126 case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32); 127 case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32); 128 case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32); 129 case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32); 130 } 131 return 0; 132} 133 134static inline int get_old_sigaction(struct k_sigaction *new_ka, 135 struct old_sigaction __user *act) 136{ 137 compat_old_sigset_t mask; 138 compat_uptr_t handler, restorer; 139 140 if (get_user(handler, &act->sa_handler) || 141 __get_user(restorer, &act->sa_restorer) || 142 __get_user(new_ka->sa.sa_flags, &act->sa_flags) || 143 __get_user(mask, &act->sa_mask)) 144 return -EFAULT; 145 new_ka->sa.sa_handler = compat_ptr(handler); 146 new_ka->sa.sa_restorer = compat_ptr(restorer); 147 siginitset(&new_ka->sa.sa_mask, mask); 148 return 0; 149} 150 151#define to_user_ptr(p) ptr_to_compat(p) 152#define from_user_ptr(p) compat_ptr(p) 153 154static inline int save_general_regs(struct pt_regs *regs, 155 struct mcontext __user *frame) 156{ 157 elf_greg_t64 *gregs = (elf_greg_t64 *)regs; 158 int i; 159 160 WARN_ON(!FULL_REGS(regs)); 161 162 for (i = 0; i <= PT_RESULT; i ++) { 163 if (i == 14 && !FULL_REGS(regs)) 164 i = 32; 165 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i])) 166 return -EFAULT; 167 } 168 return 0; 169} 170 171static inline int restore_general_regs(struct pt_regs *regs, 172 struct mcontext __user *sr) 173{ 174 elf_greg_t64 *gregs = (elf_greg_t64 *)regs; 175 int i; 176 177 for (i = 0; i <= PT_RESULT; i++) { 178 if ((i == PT_MSR) || (i == PT_SOFTE)) 179 continue; 180 if (__get_user(gregs[i], &sr->mc_gregs[i])) 181 return -EFAULT; 182 } 183 return 0; 184} 185 186#else /* CONFIG_PPC64 */ 187 188#define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs)) 189 190static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set) 191{ 192 return copy_to_user(uset, set, sizeof(*uset)); 193} 194 195static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset) 196{ 197 return copy_from_user(set, uset, sizeof(*uset)); 198} 199 200static inline int get_old_sigaction(struct k_sigaction *new_ka, 201 struct old_sigaction __user *act) 202{ 203 old_sigset_t mask; 204 205 if (!access_ok(VERIFY_READ, act, sizeof(*act)) || 206 __get_user(new_ka->sa.sa_handler, &act->sa_handler) || 207 __get_user(new_ka->sa.sa_restorer, &act->sa_restorer) || 208 __get_user(new_ka->sa.sa_flags, &act->sa_flags) || 209 __get_user(mask, &act->sa_mask)) 210 return -EFAULT; 211 siginitset(&new_ka->sa.sa_mask, mask); 212 return 0; 213} 214 215#define to_user_ptr(p) ((unsigned long)(p)) 216#define from_user_ptr(p) ((void __user *)(p)) 217 218static inline int save_general_regs(struct pt_regs *regs, 219 struct mcontext __user *frame) 220{ 221 WARN_ON(!FULL_REGS(regs)); 222 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE); 223} 224 225static inline int restore_general_regs(struct pt_regs *regs, 226 struct mcontext __user *sr) 227{ 228 /* copy up to but not including MSR */ 229 if (__copy_from_user(regs, &sr->mc_gregs, 230 PT_MSR * sizeof(elf_greg_t))) 231 return -EFAULT; 232 /* copy from orig_r3 (the word after the MSR) up to the end */ 233 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3], 234 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t))) 235 return -EFAULT; 236 return 0; 237} 238 239#endif /* CONFIG_PPC64 */ 240 241/* 242 * Atomically swap in the new signal mask, and wait for a signal. 243 */ 244long sys_sigsuspend(old_sigset_t mask) 245{ 246 sigset_t blocked; 247 siginitset(&blocked, mask); 248 return sigsuspend(&blocked); 249} 250 251long sys_sigaction(int sig, struct old_sigaction __user *act, 252 struct old_sigaction __user *oact) 253{ 254 struct k_sigaction new_ka, old_ka; 255 int ret; 256 257#ifdef CONFIG_PPC64 258 if (sig < 0) 259 sig = -sig; 260#endif 261 262 if (act) { 263 if (get_old_sigaction(&new_ka, act)) 264 return -EFAULT; 265 } 266 267 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 268 if (!ret && oact) { 269 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || 270 __put_user(to_user_ptr(old_ka.sa.sa_handler), 271 &oact->sa_handler) || 272 __put_user(to_user_ptr(old_ka.sa.sa_restorer), 273 &oact->sa_restorer) || 274 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || 275 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) 276 return -EFAULT; 277 } 278 279 return ret; 280} 281 282/* 283 * When we have signals to deliver, we set up on the 284 * user stack, going down from the original stack pointer: 285 * an ABI gap of 56 words 286 * an mcontext struct 287 * a sigcontext struct 288 * a gap of __SIGNAL_FRAMESIZE bytes 289 * 290 * Each of these things must be a multiple of 16 bytes in size. The following 291 * structure represent all of this except the __SIGNAL_FRAMESIZE gap 292 * 293 */ 294struct sigframe { 295 struct sigcontext sctx; /* the sigcontext */ 296 struct mcontext mctx; /* all the register values */ 297 /* 298 * Programs using the rs6000/xcoff abi can save up to 19 gp 299 * regs and 18 fp regs below sp before decrementing it. 300 */ 301 int abigap[56]; 302}; 303 304/* We use the mc_pad field for the signal return trampoline. */ 305#define tramp mc_pad 306 307/* 308 * When we have rt signals to deliver, we set up on the 309 * user stack, going down from the original stack pointer: 310 * one rt_sigframe struct (siginfo + ucontext + ABI gap) 311 * a gap of __SIGNAL_FRAMESIZE+16 bytes 312 * (the +16 is to get the siginfo and ucontext in the same 313 * positions as in older kernels). 314 * 315 * Each of these things must be a multiple of 16 bytes in size. 316 * 317 */ 318struct rt_sigframe { 319#ifdef CONFIG_PPC64 320 compat_siginfo_t info; 321#else 322 struct siginfo info; 323#endif 324 struct ucontext uc; 325 /* 326 * Programs using the rs6000/xcoff abi can save up to 19 gp 327 * regs and 18 fp regs below sp before decrementing it. 328 */ 329 int abigap[56]; 330}; 331 332#ifdef CONFIG_VSX 333unsigned long copy_fpr_to_user(void __user *to, 334 struct task_struct *task) 335{ 336 double buf[ELF_NFPREG]; 337 int i; 338 339 /* save FPR copy to local buffer then write to the thread_struct */ 340 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 341 buf[i] = task->thread.TS_FPR(i); 342 memcpy(&buf[i], &task->thread.fpscr, sizeof(double)); 343 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double)); 344} 345 346unsigned long copy_fpr_from_user(struct task_struct *task, 347 void __user *from) 348{ 349 double buf[ELF_NFPREG]; 350 int i; 351 352 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double))) 353 return 1; 354 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 355 task->thread.TS_FPR(i) = buf[i]; 356 memcpy(&task->thread.fpscr, &buf[i], sizeof(double)); 357 358 return 0; 359} 360 361unsigned long copy_vsx_to_user(void __user *to, 362 struct task_struct *task) 363{ 364 double buf[ELF_NVSRHALFREG]; 365 int i; 366 367 /* save FPR copy to local buffer then write to the thread_struct */ 368 for (i = 0; i < ELF_NVSRHALFREG; i++) 369 buf[i] = task->thread.fpr[i][TS_VSRLOWOFFSET]; 370 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double)); 371} 372 373unsigned long copy_vsx_from_user(struct task_struct *task, 374 void __user *from) 375{ 376 double buf[ELF_NVSRHALFREG]; 377 int i; 378 379 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double))) 380 return 1; 381 for (i = 0; i < ELF_NVSRHALFREG ; i++) 382 task->thread.fpr[i][TS_VSRLOWOFFSET] = buf[i]; 383 return 0; 384} 385#else 386inline unsigned long copy_fpr_to_user(void __user *to, 387 struct task_struct *task) 388{ 389 return __copy_to_user(to, task->thread.fpr, 390 ELF_NFPREG * sizeof(double)); 391} 392 393inline unsigned long copy_fpr_from_user(struct task_struct *task, 394 void __user *from) 395{ 396 return __copy_from_user(task->thread.fpr, from, 397 ELF_NFPREG * sizeof(double)); 398} 399#endif 400 401/* 402 * Save the current user registers on the user stack. 403 * We only save the altivec/spe registers if the process has used 404 * altivec/spe instructions at some point. 405 */ 406static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, 407 int sigret, int ctx_has_vsx_region) 408{ 409 unsigned long msr = regs->msr; 410 411 /* Make sure floating point registers are stored in regs */ 412 flush_fp_to_thread(current); 413 414 /* save general registers */ 415 if (save_general_regs(regs, frame)) 416 return 1; 417 418#ifdef CONFIG_ALTIVEC 419 /* save altivec registers */ 420 if (current->thread.used_vr) { 421 flush_altivec_to_thread(current); 422 if (__copy_to_user(&frame->mc_vregs, current->thread.vr, 423 ELF_NVRREG * sizeof(vector128))) 424 return 1; 425 /* set MSR_VEC in the saved MSR value to indicate that 426 frame->mc_vregs contains valid data */ 427 msr |= MSR_VEC; 428 } 429 /* else assert((regs->msr & MSR_VEC) == 0) */ 430 431 /* We always copy to/from vrsave, it's 0 if we don't have or don't 432 * use altivec. Since VSCR only contains 32 bits saved in the least 433 * significant bits of a vector, we "cheat" and stuff VRSAVE in the 434 * most significant bits of that same vector. --BenH 435 */ 436 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32])) 437 return 1; 438#endif /* CONFIG_ALTIVEC */ 439 if (copy_fpr_to_user(&frame->mc_fregs, current)) 440 return 1; 441#ifdef CONFIG_VSX 442 /* 443 * Copy VSR 0-31 upper half from thread_struct to local 444 * buffer, then write that to userspace. Also set MSR_VSX in 445 * the saved MSR value to indicate that frame->mc_vregs 446 * contains valid data 447 */ 448 if (current->thread.used_vsr && ctx_has_vsx_region) { 449 __giveup_vsx(current); 450 if (copy_vsx_to_user(&frame->mc_vsregs, current)) 451 return 1; 452 msr |= MSR_VSX; 453 } 454#endif /* CONFIG_VSX */ 455#ifdef CONFIG_SPE 456 /* save spe registers */ 457 if (current->thread.used_spe) { 458 flush_spe_to_thread(current); 459 if (__copy_to_user(&frame->mc_vregs, current->thread.evr, 460 ELF_NEVRREG * sizeof(u32))) 461 return 1; 462 /* set MSR_SPE in the saved MSR value to indicate that 463 frame->mc_vregs contains valid data */ 464 msr |= MSR_SPE; 465 } 466 /* else assert((regs->msr & MSR_SPE) == 0) */ 467 468 /* We always copy to/from spefscr */ 469 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG)) 470 return 1; 471#endif /* CONFIG_SPE */ 472 473 if (__put_user(msr, &frame->mc_gregs[PT_MSR])) 474 return 1; 475 if (sigret) { 476 /* Set up the sigreturn trampoline: li r0,sigret; sc */ 477 if (__put_user(0x38000000UL + sigret, &frame->tramp[0]) 478 || __put_user(0x44000002UL, &frame->tramp[1])) 479 return 1; 480 flush_icache_range((unsigned long) &frame->tramp[0], 481 (unsigned long) &frame->tramp[2]); 482 } 483 484 return 0; 485} 486 487/* 488 * Restore the current user register values from the user stack, 489 * (except for MSR). 490 */ 491static long restore_user_regs(struct pt_regs *regs, 492 struct mcontext __user *sr, int sig) 493{ 494 long err; 495 unsigned int save_r2 = 0; 496 unsigned long msr; 497#ifdef CONFIG_VSX 498 int i; 499#endif 500 501 /* 502 * restore general registers but not including MSR or SOFTE. Also 503 * take care of keeping r2 (TLS) intact if not a signal 504 */ 505 if (!sig) 506 save_r2 = (unsigned int)regs->gpr[2]; 507 err = restore_general_regs(regs, sr); 508 regs->trap = 0; 509 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]); 510 if (!sig) 511 regs->gpr[2] = (unsigned long) save_r2; 512 if (err) 513 return 1; 514 515 /* if doing signal return, restore the previous little-endian mode */ 516 if (sig) 517 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE); 518 519 /* 520 * Do this before updating the thread state in 521 * current->thread.fpr/vr/evr. That way, if we get preempted 522 * and another task grabs the FPU/Altivec/SPE, it won't be 523 * tempted to save the current CPU state into the thread_struct 524 * and corrupt what we are writing there. 525 */ 526 discard_lazy_cpu_state(); 527 528#ifdef CONFIG_ALTIVEC 529 /* 530 * Force the process to reload the altivec registers from 531 * current->thread when it next does altivec instructions 532 */ 533 regs->msr &= ~MSR_VEC; 534 if (msr & MSR_VEC) { 535 /* restore altivec registers from the stack */ 536 if (__copy_from_user(current->thread.vr, &sr->mc_vregs, 537 sizeof(sr->mc_vregs))) 538 return 1; 539 } else if (current->thread.used_vr) 540 memset(current->thread.vr, 0, ELF_NVRREG * sizeof(vector128)); 541 542 /* Always get VRSAVE back */ 543 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32])) 544 return 1; 545#endif /* CONFIG_ALTIVEC */ 546 if (copy_fpr_from_user(current, &sr->mc_fregs)) 547 return 1; 548 549#ifdef CONFIG_VSX 550 /* 551 * Force the process to reload the VSX registers from 552 * current->thread when it next does VSX instruction. 553 */ 554 regs->msr &= ~MSR_VSX; 555 if (msr & MSR_VSX) { 556 /* 557 * Restore altivec registers from the stack to a local 558 * buffer, then write this out to the thread_struct 559 */ 560 if (copy_vsx_from_user(current, &sr->mc_vsregs)) 561 return 1; 562 } else if (current->thread.used_vsr) 563 for (i = 0; i < 32 ; i++) 564 current->thread.fpr[i][TS_VSRLOWOFFSET] = 0; 565#endif /* CONFIG_VSX */ 566 /* 567 * force the process to reload the FP registers from 568 * current->thread when it next does FP instructions 569 */ 570 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1); 571 572#ifdef CONFIG_SPE 573 /* force the process to reload the spe registers from 574 current->thread when it next does spe instructions */ 575 regs->msr &= ~MSR_SPE; 576 if (msr & MSR_SPE) { 577 /* restore spe registers from the stack */ 578 if (__copy_from_user(current->thread.evr, &sr->mc_vregs, 579 ELF_NEVRREG * sizeof(u32))) 580 return 1; 581 } else if (current->thread.used_spe) 582 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32)); 583 584 /* Always get SPEFSCR back */ 585 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG)) 586 return 1; 587#endif /* CONFIG_SPE */ 588 589 return 0; 590} 591 592#ifdef CONFIG_PPC64 593long compat_sys_rt_sigaction(int sig, const struct sigaction32 __user *act, 594 struct sigaction32 __user *oact, size_t sigsetsize) 595{ 596 struct k_sigaction new_ka, old_ka; 597 int ret; 598 599 /* XXX: Don't preclude handling different sized sigset_t's. */ 600 if (sigsetsize != sizeof(compat_sigset_t)) 601 return -EINVAL; 602 603 if (act) { 604 compat_uptr_t handler; 605 606 ret = get_user(handler, &act->sa_handler); 607 new_ka.sa.sa_handler = compat_ptr(handler); 608 ret |= get_sigset_t(&new_ka.sa.sa_mask, &act->sa_mask); 609 ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags); 610 if (ret) 611 return -EFAULT; 612 } 613 614 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 615 if (!ret && oact) { 616 ret = put_user(to_user_ptr(old_ka.sa.sa_handler), &oact->sa_handler); 617 ret |= put_sigset_t(&oact->sa_mask, &old_ka.sa.sa_mask); 618 ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags); 619 } 620 return ret; 621} 622 623long compat_sys_rt_sigpending(compat_sigset_t __user *set, compat_size_t sigsetsize) 624{ 625 sigset_t s; 626 int ret; 627 mm_segment_t old_fs = get_fs(); 628 629 set_fs(KERNEL_DS); 630 /* The __user pointer cast is valid because of the set_fs() */ 631 ret = sys_rt_sigpending((sigset_t __user *) &s, sigsetsize); 632 set_fs(old_fs); 633 if (!ret) { 634 if (put_sigset_t(set, &s)) 635 return -EFAULT; 636 } 637 return ret; 638} 639 640 641int copy_siginfo_to_user32(struct compat_siginfo __user *d, siginfo_t *s) 642{ 643 int err; 644 645 if (!access_ok (VERIFY_WRITE, d, sizeof(*d))) 646 return -EFAULT; 647 648 /* If you change siginfo_t structure, please be sure 649 * this code is fixed accordingly. 650 * It should never copy any pad contained in the structure 651 * to avoid security leaks, but must copy the generic 652 * 3 ints plus the relevant union member. 653 * This routine must convert siginfo from 64bit to 32bit as well 654 * at the same time. 655 */ 656 err = __put_user(s->si_signo, &d->si_signo); 657 err |= __put_user(s->si_errno, &d->si_errno); 658 err |= __put_user((short)s->si_code, &d->si_code); 659 if (s->si_code < 0) 660 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad, 661 SI_PAD_SIZE32); 662 else switch(s->si_code >> 16) { 663 case __SI_CHLD >> 16: 664 err |= __put_user(s->si_pid, &d->si_pid); 665 err |= __put_user(s->si_uid, &d->si_uid); 666 err |= __put_user(s->si_utime, &d->si_utime); 667 err |= __put_user(s->si_stime, &d->si_stime); 668 err |= __put_user(s->si_status, &d->si_status); 669 break; 670 case __SI_FAULT >> 16: 671 err |= __put_user((unsigned int)(unsigned long)s->si_addr, 672 &d->si_addr); 673 break; 674 case __SI_POLL >> 16: 675 err |= __put_user(s->si_band, &d->si_band); 676 err |= __put_user(s->si_fd, &d->si_fd); 677 break; 678 case __SI_TIMER >> 16: 679 err |= __put_user(s->si_tid, &d->si_tid); 680 err |= __put_user(s->si_overrun, &d->si_overrun); 681 err |= __put_user(s->si_int, &d->si_int); 682 break; 683 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */ 684 case __SI_MESGQ >> 16: 685 err |= __put_user(s->si_int, &d->si_int); 686 /* fallthrough */ 687 case __SI_KILL >> 16: 688 default: 689 err |= __put_user(s->si_pid, &d->si_pid); 690 err |= __put_user(s->si_uid, &d->si_uid); 691 break; 692 } 693 return err; 694} 695 696#define copy_siginfo_to_user copy_siginfo_to_user32 697 698int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from) 699{ 700 memset(to, 0, sizeof *to); 701 702 if (copy_from_user(to, from, 3*sizeof(int)) || 703 copy_from_user(to->_sifields._pad, 704 from->_sifields._pad, SI_PAD_SIZE32)) 705 return -EFAULT; 706 707 return 0; 708} 709 710/* 711 * Note: it is necessary to treat pid and sig as unsigned ints, with the 712 * corresponding cast to a signed int to insure that the proper conversion 713 * (sign extension) between the register representation of a signed int 714 * (msr in 32-bit mode) and the register representation of a signed int 715 * (msr in 64-bit mode) is performed. 716 */ 717long compat_sys_rt_sigqueueinfo(u32 pid, u32 sig, compat_siginfo_t __user *uinfo) 718{ 719 siginfo_t info; 720 int ret; 721 mm_segment_t old_fs = get_fs(); 722 723 ret = copy_siginfo_from_user32(&info, uinfo); 724 if (unlikely(ret)) 725 return ret; 726 727 set_fs (KERNEL_DS); 728 /* The __user pointer cast is valid becasuse of the set_fs() */ 729 ret = sys_rt_sigqueueinfo((int)pid, (int)sig, (siginfo_t __user *) &info); 730 set_fs (old_fs); 731 return ret; 732} 733#endif /* CONFIG_PPC64 */ 734 735/* 736 * Set up a signal frame for a "real-time" signal handler 737 * (one which gets siginfo). 738 */ 739int handle_rt_signal32(unsigned long sig, struct k_sigaction *ka, 740 siginfo_t *info, sigset_t *oldset, 741 struct pt_regs *regs) 742{ 743 struct rt_sigframe __user *rt_sf; 744 struct mcontext __user *frame; 745 void __user *addr; 746 unsigned long newsp = 0; 747 748 /* Set up Signal Frame */ 749 /* Put a Real Time Context onto stack */ 750 rt_sf = get_sigframe(ka, regs, sizeof(*rt_sf), 1); 751 addr = rt_sf; 752 if (unlikely(rt_sf == NULL)) 753 goto badframe; 754 755 /* Put the siginfo & fill in most of the ucontext */ 756 if (copy_siginfo_to_user(&rt_sf->info, info) 757 || __put_user(0, &rt_sf->uc.uc_flags) 758 || __put_user(0, &rt_sf->uc.uc_link) 759 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1]) 760 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext), 761 &rt_sf->uc.uc_regs) 762 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset)) 763 goto badframe; 764 765 /* Save user registers on the stack */ 766 frame = &rt_sf->uc.uc_mcontext; 767 addr = frame; 768 if (vdso32_rt_sigtramp && current->mm->context.vdso_base) { 769 if (save_user_regs(regs, frame, 0, 1)) 770 goto badframe; 771 regs->link = current->mm->context.vdso_base + vdso32_rt_sigtramp; 772 } else { 773 if (save_user_regs(regs, frame, __NR_rt_sigreturn, 1)) 774 goto badframe; 775 regs->link = (unsigned long) frame->tramp; 776 } 777 778 current->thread.fpscr.val = 0; /* turn off all fp exceptions */ 779 780 /* create a stack frame for the caller of the handler */ 781 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16); 782 addr = (void __user *)regs->gpr[1]; 783 if (put_user(regs->gpr[1], (u32 __user *)newsp)) 784 goto badframe; 785 786 /* Fill registers for signal handler */ 787 regs->gpr[1] = newsp; 788 regs->gpr[3] = sig; 789 regs->gpr[4] = (unsigned long) &rt_sf->info; 790 regs->gpr[5] = (unsigned long) &rt_sf->uc; 791 regs->gpr[6] = (unsigned long) rt_sf; 792 regs->nip = (unsigned long) ka->sa.sa_handler; 793 /* enter the signal handler in big-endian mode */ 794 regs->msr &= ~MSR_LE; 795 return 1; 796 797badframe: 798#ifdef DEBUG_SIG 799 printk("badframe in handle_rt_signal, regs=%p frame=%p newsp=%lx\n", 800 regs, frame, newsp); 801#endif 802 if (show_unhandled_signals) 803 printk_ratelimited(KERN_INFO 804 "%s[%d]: bad frame in handle_rt_signal32: " 805 "%p nip %08lx lr %08lx\n", 806 current->comm, current->pid, 807 addr, regs->nip, regs->link); 808 809 force_sigsegv(sig, current); 810 return 0; 811} 812 813static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig) 814{ 815 sigset_t set; 816 struct mcontext __user *mcp; 817 818 if (get_sigset_t(&set, &ucp->uc_sigmask)) 819 return -EFAULT; 820#ifdef CONFIG_PPC64 821 { 822 u32 cmcp; 823 824 if (__get_user(cmcp, &ucp->uc_regs)) 825 return -EFAULT; 826 mcp = (struct mcontext __user *)(u64)cmcp; 827 /* no need to check access_ok(mcp), since mcp < 4GB */ 828 } 829#else 830 if (__get_user(mcp, &ucp->uc_regs)) 831 return -EFAULT; 832 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp))) 833 return -EFAULT; 834#endif 835 set_current_blocked(&set); 836 if (restore_user_regs(regs, mcp, sig)) 837 return -EFAULT; 838 839 return 0; 840} 841 842long sys_swapcontext(struct ucontext __user *old_ctx, 843 struct ucontext __user *new_ctx, 844 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs) 845{ 846 unsigned char tmp; 847 int ctx_has_vsx_region = 0; 848 849#ifdef CONFIG_PPC64 850 unsigned long new_msr = 0; 851 852 if (new_ctx) { 853 struct mcontext __user *mcp; 854 u32 cmcp; 855 856 /* 857 * Get pointer to the real mcontext. No need for 858 * access_ok since we are dealing with compat 859 * pointers. 860 */ 861 if (__get_user(cmcp, &new_ctx->uc_regs)) 862 return -EFAULT; 863 mcp = (struct mcontext __user *)(u64)cmcp; 864 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR])) 865 return -EFAULT; 866 } 867 /* 868 * Check that the context is not smaller than the original 869 * size (with VMX but without VSX) 870 */ 871 if (ctx_size < UCONTEXTSIZEWITHOUTVSX) 872 return -EINVAL; 873 /* 874 * If the new context state sets the MSR VSX bits but 875 * it doesn't provide VSX state. 876 */ 877 if ((ctx_size < sizeof(struct ucontext)) && 878 (new_msr & MSR_VSX)) 879 return -EINVAL; 880 /* Does the context have enough room to store VSX data? */ 881 if (ctx_size >= sizeof(struct ucontext)) 882 ctx_has_vsx_region = 1; 883#else 884 /* Context size is for future use. Right now, we only make sure 885 * we are passed something we understand 886 */ 887 if (ctx_size < sizeof(struct ucontext)) 888 return -EINVAL; 889#endif 890 if (old_ctx != NULL) { 891 struct mcontext __user *mctx; 892 893 /* 894 * old_ctx might not be 16-byte aligned, in which 895 * case old_ctx->uc_mcontext won't be either. 896 * Because we have the old_ctx->uc_pad2 field 897 * before old_ctx->uc_mcontext, we need to round down 898 * from &old_ctx->uc_mcontext to a 16-byte boundary. 899 */ 900 mctx = (struct mcontext __user *) 901 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL); 902 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size) 903 || save_user_regs(regs, mctx, 0, ctx_has_vsx_region) 904 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked) 905 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs)) 906 return -EFAULT; 907 } 908 if (new_ctx == NULL) 909 return 0; 910 if (!access_ok(VERIFY_READ, new_ctx, ctx_size) 911 || __get_user(tmp, (u8 __user *) new_ctx) 912 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1)) 913 return -EFAULT; 914 915 /* 916 * If we get a fault copying the context into the kernel's 917 * image of the user's registers, we can't just return -EFAULT 918 * because the user's registers will be corrupted. For instance 919 * the NIP value may have been updated but not some of the 920 * other registers. Given that we have done the access_ok 921 * and successfully read the first and last bytes of the region 922 * above, this should only happen in an out-of-memory situation 923 * or if another thread unmaps the region containing the context. 924 * We kill the task with a SIGSEGV in this situation. 925 */ 926 if (do_setcontext(new_ctx, regs, 0)) 927 do_exit(SIGSEGV); 928 929 set_thread_flag(TIF_RESTOREALL); 930 return 0; 931} 932 933long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, 934 struct pt_regs *regs) 935{ 936 struct rt_sigframe __user *rt_sf; 937 938 /* Always make any pending restarted system calls return -EINTR */ 939 current_thread_info()->restart_block.fn = do_no_restart_syscall; 940 941 rt_sf = (struct rt_sigframe __user *) 942 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16); 943 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf))) 944 goto bad; 945 if (do_setcontext(&rt_sf->uc, regs, 1)) 946 goto bad; 947 948 /* 949 * It's not clear whether or why it is desirable to save the 950 * sigaltstack setting on signal delivery and restore it on 951 * signal return. But other architectures do this and we have 952 * always done it up until now so it is probably better not to 953 * change it. -- paulus 954 */ 955#ifdef CONFIG_PPC64 956 if (compat_restore_altstack(&rt_sf->uc.uc_stack)) 957 goto bad; 958#else 959 if (restore_altstack(&rt_sf->uc.uc_stack)) 960 goto bad; 961#endif 962 set_thread_flag(TIF_RESTOREALL); 963 return 0; 964 965 bad: 966 if (show_unhandled_signals) 967 printk_ratelimited(KERN_INFO 968 "%s[%d]: bad frame in sys_rt_sigreturn: " 969 "%p nip %08lx lr %08lx\n", 970 current->comm, current->pid, 971 rt_sf, regs->nip, regs->link); 972 973 force_sig(SIGSEGV, current); 974 return 0; 975} 976 977#ifdef CONFIG_PPC32 978int sys_debug_setcontext(struct ucontext __user *ctx, 979 int ndbg, struct sig_dbg_op __user *dbg, 980 int r6, int r7, int r8, 981 struct pt_regs *regs) 982{ 983 struct sig_dbg_op op; 984 int i; 985 unsigned char tmp; 986 unsigned long new_msr = regs->msr; 987#ifdef CONFIG_PPC_ADV_DEBUG_REGS 988 unsigned long new_dbcr0 = current->thread.dbcr0; 989#endif 990 991 for (i=0; i<ndbg; i++) { 992 if (copy_from_user(&op, dbg + i, sizeof(op))) 993 return -EFAULT; 994 switch (op.dbg_type) { 995 case SIG_DBG_SINGLE_STEPPING: 996#ifdef CONFIG_PPC_ADV_DEBUG_REGS 997 if (op.dbg_value) { 998 new_msr |= MSR_DE; 999 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC); 1000 } else { 1001 new_dbcr0 &= ~DBCR0_IC; 1002 if (!DBCR_ACTIVE_EVENTS(new_dbcr0, 1003 current->thread.dbcr1)) { 1004 new_msr &= ~MSR_DE; 1005 new_dbcr0 &= ~DBCR0_IDM; 1006 } 1007 } 1008#else 1009 if (op.dbg_value) 1010 new_msr |= MSR_SE; 1011 else 1012 new_msr &= ~MSR_SE; 1013#endif 1014 break; 1015 case SIG_DBG_BRANCH_TRACING: 1016#ifdef CONFIG_PPC_ADV_DEBUG_REGS 1017 return -EINVAL; 1018#else 1019 if (op.dbg_value) 1020 new_msr |= MSR_BE; 1021 else 1022 new_msr &= ~MSR_BE; 1023#endif 1024 break; 1025 1026 default: 1027 return -EINVAL; 1028 } 1029 } 1030 1031 /* We wait until here to actually install the values in the 1032 registers so if we fail in the above loop, it will not 1033 affect the contents of these registers. After this point, 1034 failure is a problem, anyway, and it's very unlikely unless 1035 the user is really doing something wrong. */ 1036 regs->msr = new_msr; 1037#ifdef CONFIG_PPC_ADV_DEBUG_REGS 1038 current->thread.dbcr0 = new_dbcr0; 1039#endif 1040 1041 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx)) 1042 || __get_user(tmp, (u8 __user *) ctx) 1043 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1)) 1044 return -EFAULT; 1045 1046 /* 1047 * If we get a fault copying the context into the kernel's 1048 * image of the user's registers, we can't just return -EFAULT 1049 * because the user's registers will be corrupted. For instance 1050 * the NIP value may have been updated but not some of the 1051 * other registers. Given that we have done the access_ok 1052 * and successfully read the first and last bytes of the region 1053 * above, this should only happen in an out-of-memory situation 1054 * or if another thread unmaps the region containing the context. 1055 * We kill the task with a SIGSEGV in this situation. 1056 */ 1057 if (do_setcontext(ctx, regs, 1)) { 1058 if (show_unhandled_signals) 1059 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in " 1060 "sys_debug_setcontext: %p nip %08lx " 1061 "lr %08lx\n", 1062 current->comm, current->pid, 1063 ctx, regs->nip, regs->link); 1064 1065 force_sig(SIGSEGV, current); 1066 goto out; 1067 } 1068 1069 /* 1070 * It's not clear whether or why it is desirable to save the 1071 * sigaltstack setting on signal delivery and restore it on 1072 * signal return. But other architectures do this and we have 1073 * always done it up until now so it is probably better not to 1074 * change it. -- paulus 1075 */ 1076 restore_altstack(&ctx->uc_stack); 1077 1078 set_thread_flag(TIF_RESTOREALL); 1079 out: 1080 return 0; 1081} 1082#endif 1083 1084/* 1085 * OK, we're invoking a handler 1086 */ 1087int handle_signal32(unsigned long sig, struct k_sigaction *ka, 1088 siginfo_t *info, sigset_t *oldset, struct pt_regs *regs) 1089{ 1090 struct sigcontext __user *sc; 1091 struct sigframe __user *frame; 1092 unsigned long newsp = 0; 1093 1094 /* Set up Signal Frame */ 1095 frame = get_sigframe(ka, regs, sizeof(*frame), 1); 1096 if (unlikely(frame == NULL)) 1097 goto badframe; 1098 sc = (struct sigcontext __user *) &frame->sctx; 1099 1100#if _NSIG != 64 1101#error "Please adjust handle_signal()" 1102#endif 1103 if (__put_user(to_user_ptr(ka->sa.sa_handler), &sc->handler) 1104 || __put_user(oldset->sig[0], &sc->oldmask) 1105#ifdef CONFIG_PPC64 1106 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3]) 1107#else 1108 || __put_user(oldset->sig[1], &sc->_unused[3]) 1109#endif 1110 || __put_user(to_user_ptr(&frame->mctx), &sc->regs) 1111 || __put_user(sig, &sc->signal)) 1112 goto badframe; 1113 1114 if (vdso32_sigtramp && current->mm->context.vdso_base) { 1115 if (save_user_regs(regs, &frame->mctx, 0, 1)) 1116 goto badframe; 1117 regs->link = current->mm->context.vdso_base + vdso32_sigtramp; 1118 } else { 1119 if (save_user_regs(regs, &frame->mctx, __NR_sigreturn, 1)) 1120 goto badframe; 1121 regs->link = (unsigned long) frame->mctx.tramp; 1122 } 1123 1124 current->thread.fpscr.val = 0; /* turn off all fp exceptions */ 1125 1126 /* create a stack frame for the caller of the handler */ 1127 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE; 1128 if (put_user(regs->gpr[1], (u32 __user *)newsp)) 1129 goto badframe; 1130 1131 regs->gpr[1] = newsp; 1132 regs->gpr[3] = sig; 1133 regs->gpr[4] = (unsigned long) sc; 1134 regs->nip = (unsigned long) ka->sa.sa_handler; 1135 /* enter the signal handler in big-endian mode */ 1136 regs->msr &= ~MSR_LE; 1137 1138 return 1; 1139 1140badframe: 1141#ifdef DEBUG_SIG 1142 printk("badframe in handle_signal, regs=%p frame=%p newsp=%lx\n", 1143 regs, frame, newsp); 1144#endif 1145 if (show_unhandled_signals) 1146 printk_ratelimited(KERN_INFO 1147 "%s[%d]: bad frame in handle_signal32: " 1148 "%p nip %08lx lr %08lx\n", 1149 current->comm, current->pid, 1150 frame, regs->nip, regs->link); 1151 1152 force_sigsegv(sig, current); 1153 return 0; 1154} 1155 1156/* 1157 * Do a signal return; undo the signal stack. 1158 */ 1159long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, 1160 struct pt_regs *regs) 1161{ 1162 struct sigcontext __user *sc; 1163 struct sigcontext sigctx; 1164 struct mcontext __user *sr; 1165 void __user *addr; 1166 sigset_t set; 1167 1168 /* Always make any pending restarted system calls return -EINTR */ 1169 current_thread_info()->restart_block.fn = do_no_restart_syscall; 1170 1171 sc = (struct sigcontext __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE); 1172 addr = sc; 1173 if (copy_from_user(&sigctx, sc, sizeof(sigctx))) 1174 goto badframe; 1175 1176#ifdef CONFIG_PPC64 1177 /* 1178 * Note that PPC32 puts the upper 32 bits of the sigmask in the 1179 * unused part of the signal stackframe 1180 */ 1181 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32); 1182#else 1183 set.sig[0] = sigctx.oldmask; 1184 set.sig[1] = sigctx._unused[3]; 1185#endif 1186 set_current_blocked(&set); 1187 1188 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs); 1189 addr = sr; 1190 if (!access_ok(VERIFY_READ, sr, sizeof(*sr)) 1191 || restore_user_regs(regs, sr, 1)) 1192 goto badframe; 1193 1194 set_thread_flag(TIF_RESTOREALL); 1195 return 0; 1196 1197badframe: 1198 if (show_unhandled_signals) 1199 printk_ratelimited(KERN_INFO 1200 "%s[%d]: bad frame in sys_sigreturn: " 1201 "%p nip %08lx lr %08lx\n", 1202 current->comm, current->pid, 1203 addr, regs->nip, regs->link); 1204 1205 force_sig(SIGSEGV, current); 1206 return 0; 1207} 1208