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 #include <asm/tm.h> 47 #ifdef CONFIG_PPC64 48 #include "ppc32.h" 49 #include <asm/unistd.h> 50 #else 51 #include <asm/ucontext.h> 52 #include <asm/pgtable.h> 53 #endif 54 55 #include "signal.h" 56 57 58 #ifdef CONFIG_PPC64 59 #define sys_rt_sigreturn compat_sys_rt_sigreturn 60 #define sys_swapcontext compat_sys_swapcontext 61 #define sys_sigreturn compat_sys_sigreturn 62 63 #define old_sigaction old_sigaction32 64 #define sigcontext sigcontext32 65 #define mcontext mcontext32 66 #define ucontext ucontext32 67 68 #define __save_altstack __compat_save_altstack 69 70 /* 71 * Userspace code may pass a ucontext which doesn't include VSX added 72 * at the end. We need to check for this case. 73 */ 74 #define UCONTEXTSIZEWITHOUTVSX \ 75 (sizeof(struct ucontext) - sizeof(elf_vsrreghalf_t32)) 76 77 /* 78 * Returning 0 means we return to userspace via 79 * ret_from_except and thus restore all user 80 * registers from *regs. This is what we need 81 * to do when a signal has been delivered. 82 */ 83 84 #define GP_REGS_SIZE min(sizeof(elf_gregset_t32), sizeof(struct pt_regs32)) 85 #undef __SIGNAL_FRAMESIZE 86 #define __SIGNAL_FRAMESIZE __SIGNAL_FRAMESIZE32 87 #undef ELF_NVRREG 88 #define ELF_NVRREG ELF_NVRREG32 89 90 /* 91 * Functions for flipping sigsets (thanks to brain dead generic 92 * implementation that makes things simple for little endian only) 93 */ 94 static inline int put_sigset_t(compat_sigset_t __user *uset, sigset_t *set) 95 { 96 compat_sigset_t cset; 97 98 switch (_NSIG_WORDS) { 99 case 4: cset.sig[6] = set->sig[3] & 0xffffffffull; 100 cset.sig[7] = set->sig[3] >> 32; 101 case 3: cset.sig[4] = set->sig[2] & 0xffffffffull; 102 cset.sig[5] = set->sig[2] >> 32; 103 case 2: cset.sig[2] = set->sig[1] & 0xffffffffull; 104 cset.sig[3] = set->sig[1] >> 32; 105 case 1: cset.sig[0] = set->sig[0] & 0xffffffffull; 106 cset.sig[1] = set->sig[0] >> 32; 107 } 108 return copy_to_user(uset, &cset, sizeof(*uset)); 109 } 110 111 static inline int get_sigset_t(sigset_t *set, 112 const compat_sigset_t __user *uset) 113 { 114 compat_sigset_t s32; 115 116 if (copy_from_user(&s32, uset, sizeof(*uset))) 117 return -EFAULT; 118 119 /* 120 * Swap the 2 words of the 64-bit sigset_t (they are stored 121 * in the "wrong" endian in 32-bit user storage). 122 */ 123 switch (_NSIG_WORDS) { 124 case 4: set->sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32); 125 case 3: set->sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32); 126 case 2: set->sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32); 127 case 1: set->sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32); 128 } 129 return 0; 130 } 131 132 #define to_user_ptr(p) ptr_to_compat(p) 133 #define from_user_ptr(p) compat_ptr(p) 134 135 static inline int save_general_regs(struct pt_regs *regs, 136 struct mcontext __user *frame) 137 { 138 elf_greg_t64 *gregs = (elf_greg_t64 *)regs; 139 int i; 140 141 WARN_ON(!FULL_REGS(regs)); 142 143 for (i = 0; i <= PT_RESULT; i ++) { 144 if (i == 14 && !FULL_REGS(regs)) 145 i = 32; 146 if (__put_user((unsigned int)gregs[i], &frame->mc_gregs[i])) 147 return -EFAULT; 148 } 149 return 0; 150 } 151 152 static inline int restore_general_regs(struct pt_regs *regs, 153 struct mcontext __user *sr) 154 { 155 elf_greg_t64 *gregs = (elf_greg_t64 *)regs; 156 int i; 157 158 for (i = 0; i <= PT_RESULT; i++) { 159 if ((i == PT_MSR) || (i == PT_SOFTE)) 160 continue; 161 if (__get_user(gregs[i], &sr->mc_gregs[i])) 162 return -EFAULT; 163 } 164 return 0; 165 } 166 167 #else /* CONFIG_PPC64 */ 168 169 #define GP_REGS_SIZE min(sizeof(elf_gregset_t), sizeof(struct pt_regs)) 170 171 static inline int put_sigset_t(sigset_t __user *uset, sigset_t *set) 172 { 173 return copy_to_user(uset, set, sizeof(*uset)); 174 } 175 176 static inline int get_sigset_t(sigset_t *set, const sigset_t __user *uset) 177 { 178 return copy_from_user(set, uset, sizeof(*uset)); 179 } 180 181 #define to_user_ptr(p) ((unsigned long)(p)) 182 #define from_user_ptr(p) ((void __user *)(p)) 183 184 static inline int save_general_regs(struct pt_regs *regs, 185 struct mcontext __user *frame) 186 { 187 WARN_ON(!FULL_REGS(regs)); 188 return __copy_to_user(&frame->mc_gregs, regs, GP_REGS_SIZE); 189 } 190 191 static inline int restore_general_regs(struct pt_regs *regs, 192 struct mcontext __user *sr) 193 { 194 /* copy up to but not including MSR */ 195 if (__copy_from_user(regs, &sr->mc_gregs, 196 PT_MSR * sizeof(elf_greg_t))) 197 return -EFAULT; 198 /* copy from orig_r3 (the word after the MSR) up to the end */ 199 if (__copy_from_user(®s->orig_gpr3, &sr->mc_gregs[PT_ORIG_R3], 200 GP_REGS_SIZE - PT_ORIG_R3 * sizeof(elf_greg_t))) 201 return -EFAULT; 202 return 0; 203 } 204 #endif 205 206 /* 207 * When we have signals to deliver, we set up on the 208 * user stack, going down from the original stack pointer: 209 * an ABI gap of 56 words 210 * an mcontext struct 211 * a sigcontext struct 212 * a gap of __SIGNAL_FRAMESIZE bytes 213 * 214 * Each of these things must be a multiple of 16 bytes in size. The following 215 * structure represent all of this except the __SIGNAL_FRAMESIZE gap 216 * 217 */ 218 struct sigframe { 219 struct sigcontext sctx; /* the sigcontext */ 220 struct mcontext mctx; /* all the register values */ 221 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 222 struct sigcontext sctx_transact; 223 struct mcontext mctx_transact; 224 #endif 225 /* 226 * Programs using the rs6000/xcoff abi can save up to 19 gp 227 * regs and 18 fp regs below sp before decrementing it. 228 */ 229 int abigap[56]; 230 }; 231 232 /* We use the mc_pad field for the signal return trampoline. */ 233 #define tramp mc_pad 234 235 /* 236 * When we have rt signals to deliver, we set up on the 237 * user stack, going down from the original stack pointer: 238 * one rt_sigframe struct (siginfo + ucontext + ABI gap) 239 * a gap of __SIGNAL_FRAMESIZE+16 bytes 240 * (the +16 is to get the siginfo and ucontext in the same 241 * positions as in older kernels). 242 * 243 * Each of these things must be a multiple of 16 bytes in size. 244 * 245 */ 246 struct rt_sigframe { 247 #ifdef CONFIG_PPC64 248 compat_siginfo_t info; 249 #else 250 struct siginfo info; 251 #endif 252 struct ucontext uc; 253 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 254 struct ucontext uc_transact; 255 #endif 256 /* 257 * Programs using the rs6000/xcoff abi can save up to 19 gp 258 * regs and 18 fp regs below sp before decrementing it. 259 */ 260 int abigap[56]; 261 }; 262 263 #ifdef CONFIG_VSX 264 unsigned long copy_fpr_to_user(void __user *to, 265 struct task_struct *task) 266 { 267 u64 buf[ELF_NFPREG]; 268 int i; 269 270 /* save FPR copy to local buffer then write to the thread_struct */ 271 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 272 buf[i] = task->thread.TS_FPR(i); 273 buf[i] = task->thread.fp_state.fpscr; 274 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double)); 275 } 276 277 unsigned long copy_fpr_from_user(struct task_struct *task, 278 void __user *from) 279 { 280 u64 buf[ELF_NFPREG]; 281 int i; 282 283 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double))) 284 return 1; 285 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 286 task->thread.TS_FPR(i) = buf[i]; 287 task->thread.fp_state.fpscr = buf[i]; 288 289 return 0; 290 } 291 292 unsigned long copy_vsx_to_user(void __user *to, 293 struct task_struct *task) 294 { 295 u64 buf[ELF_NVSRHALFREG]; 296 int i; 297 298 /* save FPR copy to local buffer then write to the thread_struct */ 299 for (i = 0; i < ELF_NVSRHALFREG; i++) 300 buf[i] = task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET]; 301 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double)); 302 } 303 304 unsigned long copy_vsx_from_user(struct task_struct *task, 305 void __user *from) 306 { 307 u64 buf[ELF_NVSRHALFREG]; 308 int i; 309 310 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double))) 311 return 1; 312 for (i = 0; i < ELF_NVSRHALFREG ; i++) 313 task->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = buf[i]; 314 return 0; 315 } 316 317 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 318 unsigned long copy_transact_fpr_to_user(void __user *to, 319 struct task_struct *task) 320 { 321 u64 buf[ELF_NFPREG]; 322 int i; 323 324 /* save FPR copy to local buffer then write to the thread_struct */ 325 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 326 buf[i] = task->thread.TS_TRANS_FPR(i); 327 buf[i] = task->thread.transact_fp.fpscr; 328 return __copy_to_user(to, buf, ELF_NFPREG * sizeof(double)); 329 } 330 331 unsigned long copy_transact_fpr_from_user(struct task_struct *task, 332 void __user *from) 333 { 334 u64 buf[ELF_NFPREG]; 335 int i; 336 337 if (__copy_from_user(buf, from, ELF_NFPREG * sizeof(double))) 338 return 1; 339 for (i = 0; i < (ELF_NFPREG - 1) ; i++) 340 task->thread.TS_TRANS_FPR(i) = buf[i]; 341 task->thread.transact_fp.fpscr = buf[i]; 342 343 return 0; 344 } 345 346 unsigned long copy_transact_vsx_to_user(void __user *to, 347 struct task_struct *task) 348 { 349 u64 buf[ELF_NVSRHALFREG]; 350 int i; 351 352 /* save FPR copy to local buffer then write to the thread_struct */ 353 for (i = 0; i < ELF_NVSRHALFREG; i++) 354 buf[i] = task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET]; 355 return __copy_to_user(to, buf, ELF_NVSRHALFREG * sizeof(double)); 356 } 357 358 unsigned long copy_transact_vsx_from_user(struct task_struct *task, 359 void __user *from) 360 { 361 u64 buf[ELF_NVSRHALFREG]; 362 int i; 363 364 if (__copy_from_user(buf, from, ELF_NVSRHALFREG * sizeof(double))) 365 return 1; 366 for (i = 0; i < ELF_NVSRHALFREG ; i++) 367 task->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = buf[i]; 368 return 0; 369 } 370 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ 371 #else 372 inline unsigned long copy_fpr_to_user(void __user *to, 373 struct task_struct *task) 374 { 375 return __copy_to_user(to, task->thread.fp_state.fpr, 376 ELF_NFPREG * sizeof(double)); 377 } 378 379 inline unsigned long copy_fpr_from_user(struct task_struct *task, 380 void __user *from) 381 { 382 return __copy_from_user(task->thread.fp_state.fpr, from, 383 ELF_NFPREG * sizeof(double)); 384 } 385 386 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 387 inline unsigned long copy_transact_fpr_to_user(void __user *to, 388 struct task_struct *task) 389 { 390 return __copy_to_user(to, task->thread.transact_fp.fpr, 391 ELF_NFPREG * sizeof(double)); 392 } 393 394 inline unsigned long copy_transact_fpr_from_user(struct task_struct *task, 395 void __user *from) 396 { 397 return __copy_from_user(task->thread.transact_fp.fpr, from, 398 ELF_NFPREG * sizeof(double)); 399 } 400 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ 401 #endif 402 403 /* 404 * Save the current user registers on the user stack. 405 * We only save the altivec/spe registers if the process has used 406 * altivec/spe instructions at some point. 407 */ 408 static int save_user_regs(struct pt_regs *regs, struct mcontext __user *frame, 409 struct mcontext __user *tm_frame, int sigret, 410 int ctx_has_vsx_region) 411 { 412 unsigned long msr = regs->msr; 413 414 /* Make sure floating point registers are stored in regs */ 415 flush_fp_to_thread(current); 416 417 /* save general registers */ 418 if (save_general_regs(regs, frame)) 419 return 1; 420 421 #ifdef CONFIG_ALTIVEC 422 /* save altivec registers */ 423 if (current->thread.used_vr) { 424 flush_altivec_to_thread(current); 425 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state, 426 ELF_NVRREG * sizeof(vector128))) 427 return 1; 428 /* set MSR_VEC in the saved MSR value to indicate that 429 frame->mc_vregs contains valid data */ 430 msr |= MSR_VEC; 431 } 432 /* else assert((regs->msr & MSR_VEC) == 0) */ 433 434 /* We always copy to/from vrsave, it's 0 if we don't have or don't 435 * use altivec. Since VSCR only contains 32 bits saved in the least 436 * significant bits of a vector, we "cheat" and stuff VRSAVE in the 437 * most significant bits of that same vector. --BenH 438 * Note that the current VRSAVE value is in the SPR at this point. 439 */ 440 if (cpu_has_feature(CPU_FTR_ALTIVEC)) 441 current->thread.vrsave = mfspr(SPRN_VRSAVE); 442 if (__put_user(current->thread.vrsave, (u32 __user *)&frame->mc_vregs[32])) 443 return 1; 444 #endif /* CONFIG_ALTIVEC */ 445 if (copy_fpr_to_user(&frame->mc_fregs, current)) 446 return 1; 447 448 /* 449 * Clear the MSR VSX bit to indicate there is no valid state attached 450 * to this context, except in the specific case below where we set it. 451 */ 452 msr &= ~MSR_VSX; 453 #ifdef CONFIG_VSX 454 /* 455 * Copy VSR 0-31 upper half from thread_struct to local 456 * buffer, then write that to userspace. Also set MSR_VSX in 457 * the saved MSR value to indicate that frame->mc_vregs 458 * contains valid data 459 */ 460 if (current->thread.used_vsr && ctx_has_vsx_region) { 461 __giveup_vsx(current); 462 if (copy_vsx_to_user(&frame->mc_vsregs, current)) 463 return 1; 464 msr |= MSR_VSX; 465 } 466 #endif /* CONFIG_VSX */ 467 #ifdef CONFIG_SPE 468 /* save spe registers */ 469 if (current->thread.used_spe) { 470 flush_spe_to_thread(current); 471 if (__copy_to_user(&frame->mc_vregs, current->thread.evr, 472 ELF_NEVRREG * sizeof(u32))) 473 return 1; 474 /* set MSR_SPE in the saved MSR value to indicate that 475 frame->mc_vregs contains valid data */ 476 msr |= MSR_SPE; 477 } 478 /* else assert((regs->msr & MSR_SPE) == 0) */ 479 480 /* We always copy to/from spefscr */ 481 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG)) 482 return 1; 483 #endif /* CONFIG_SPE */ 484 485 if (__put_user(msr, &frame->mc_gregs[PT_MSR])) 486 return 1; 487 /* We need to write 0 the MSR top 32 bits in the tm frame so that we 488 * can check it on the restore to see if TM is active 489 */ 490 if (tm_frame && __put_user(0, &tm_frame->mc_gregs[PT_MSR])) 491 return 1; 492 493 if (sigret) { 494 /* Set up the sigreturn trampoline: li r0,sigret; sc */ 495 if (__put_user(0x38000000UL + sigret, &frame->tramp[0]) 496 || __put_user(0x44000002UL, &frame->tramp[1])) 497 return 1; 498 flush_icache_range((unsigned long) &frame->tramp[0], 499 (unsigned long) &frame->tramp[2]); 500 } 501 502 return 0; 503 } 504 505 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 506 /* 507 * Save the current user registers on the user stack. 508 * We only save the altivec/spe registers if the process has used 509 * altivec/spe instructions at some point. 510 * We also save the transactional registers to a second ucontext in the 511 * frame. 512 * 513 * See save_user_regs() and signal_64.c:setup_tm_sigcontexts(). 514 */ 515 static int save_tm_user_regs(struct pt_regs *regs, 516 struct mcontext __user *frame, 517 struct mcontext __user *tm_frame, int sigret) 518 { 519 unsigned long msr = regs->msr; 520 521 /* Remove TM bits from thread's MSR. The MSR in the sigcontext 522 * just indicates to userland that we were doing a transaction, but we 523 * don't want to return in transactional state. This also ensures 524 * that flush_fp_to_thread won't set TIF_RESTORE_TM again. 525 */ 526 regs->msr &= ~MSR_TS_MASK; 527 528 /* Make sure floating point registers are stored in regs */ 529 flush_fp_to_thread(current); 530 531 /* Save both sets of general registers */ 532 if (save_general_regs(¤t->thread.ckpt_regs, frame) 533 || save_general_regs(regs, tm_frame)) 534 return 1; 535 536 /* Stash the top half of the 64bit MSR into the 32bit MSR word 537 * of the transactional mcontext. This way we have a backward-compatible 538 * MSR in the 'normal' (checkpointed) mcontext and additionally one can 539 * also look at what type of transaction (T or S) was active at the 540 * time of the signal. 541 */ 542 if (__put_user((msr >> 32), &tm_frame->mc_gregs[PT_MSR])) 543 return 1; 544 545 #ifdef CONFIG_ALTIVEC 546 /* save altivec registers */ 547 if (current->thread.used_vr) { 548 flush_altivec_to_thread(current); 549 if (__copy_to_user(&frame->mc_vregs, ¤t->thread.vr_state, 550 ELF_NVRREG * sizeof(vector128))) 551 return 1; 552 if (msr & MSR_VEC) { 553 if (__copy_to_user(&tm_frame->mc_vregs, 554 ¤t->thread.transact_vr, 555 ELF_NVRREG * sizeof(vector128))) 556 return 1; 557 } else { 558 if (__copy_to_user(&tm_frame->mc_vregs, 559 ¤t->thread.vr_state, 560 ELF_NVRREG * sizeof(vector128))) 561 return 1; 562 } 563 564 /* set MSR_VEC in the saved MSR value to indicate that 565 * frame->mc_vregs contains valid data 566 */ 567 msr |= MSR_VEC; 568 } 569 570 /* We always copy to/from vrsave, it's 0 if we don't have or don't 571 * use altivec. Since VSCR only contains 32 bits saved in the least 572 * significant bits of a vector, we "cheat" and stuff VRSAVE in the 573 * most significant bits of that same vector. --BenH 574 */ 575 if (cpu_has_feature(CPU_FTR_ALTIVEC)) 576 current->thread.vrsave = mfspr(SPRN_VRSAVE); 577 if (__put_user(current->thread.vrsave, 578 (u32 __user *)&frame->mc_vregs[32])) 579 return 1; 580 if (msr & MSR_VEC) { 581 if (__put_user(current->thread.transact_vrsave, 582 (u32 __user *)&tm_frame->mc_vregs[32])) 583 return 1; 584 } else { 585 if (__put_user(current->thread.vrsave, 586 (u32 __user *)&tm_frame->mc_vregs[32])) 587 return 1; 588 } 589 #endif /* CONFIG_ALTIVEC */ 590 591 if (copy_fpr_to_user(&frame->mc_fregs, current)) 592 return 1; 593 if (msr & MSR_FP) { 594 if (copy_transact_fpr_to_user(&tm_frame->mc_fregs, current)) 595 return 1; 596 } else { 597 if (copy_fpr_to_user(&tm_frame->mc_fregs, current)) 598 return 1; 599 } 600 601 #ifdef CONFIG_VSX 602 /* 603 * Copy VSR 0-31 upper half from thread_struct to local 604 * buffer, then write that to userspace. Also set MSR_VSX in 605 * the saved MSR value to indicate that frame->mc_vregs 606 * contains valid data 607 */ 608 if (current->thread.used_vsr) { 609 __giveup_vsx(current); 610 if (copy_vsx_to_user(&frame->mc_vsregs, current)) 611 return 1; 612 if (msr & MSR_VSX) { 613 if (copy_transact_vsx_to_user(&tm_frame->mc_vsregs, 614 current)) 615 return 1; 616 } else { 617 if (copy_vsx_to_user(&tm_frame->mc_vsregs, current)) 618 return 1; 619 } 620 621 msr |= MSR_VSX; 622 } 623 #endif /* CONFIG_VSX */ 624 #ifdef CONFIG_SPE 625 /* SPE regs are not checkpointed with TM, so this section is 626 * simply the same as in save_user_regs(). 627 */ 628 if (current->thread.used_spe) { 629 flush_spe_to_thread(current); 630 if (__copy_to_user(&frame->mc_vregs, current->thread.evr, 631 ELF_NEVRREG * sizeof(u32))) 632 return 1; 633 /* set MSR_SPE in the saved MSR value to indicate that 634 * frame->mc_vregs contains valid data */ 635 msr |= MSR_SPE; 636 } 637 638 /* We always copy to/from spefscr */ 639 if (__put_user(current->thread.spefscr, (u32 __user *)&frame->mc_vregs + ELF_NEVRREG)) 640 return 1; 641 #endif /* CONFIG_SPE */ 642 643 if (__put_user(msr, &frame->mc_gregs[PT_MSR])) 644 return 1; 645 if (sigret) { 646 /* Set up the sigreturn trampoline: li r0,sigret; sc */ 647 if (__put_user(0x38000000UL + sigret, &frame->tramp[0]) 648 || __put_user(0x44000002UL, &frame->tramp[1])) 649 return 1; 650 flush_icache_range((unsigned long) &frame->tramp[0], 651 (unsigned long) &frame->tramp[2]); 652 } 653 654 return 0; 655 } 656 #endif 657 658 /* 659 * Restore the current user register values from the user stack, 660 * (except for MSR). 661 */ 662 static long restore_user_regs(struct pt_regs *regs, 663 struct mcontext __user *sr, int sig) 664 { 665 long err; 666 unsigned int save_r2 = 0; 667 unsigned long msr; 668 #ifdef CONFIG_VSX 669 int i; 670 #endif 671 672 /* 673 * restore general registers but not including MSR or SOFTE. Also 674 * take care of keeping r2 (TLS) intact if not a signal 675 */ 676 if (!sig) 677 save_r2 = (unsigned int)regs->gpr[2]; 678 err = restore_general_regs(regs, sr); 679 regs->trap = 0; 680 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]); 681 if (!sig) 682 regs->gpr[2] = (unsigned long) save_r2; 683 if (err) 684 return 1; 685 686 /* if doing signal return, restore the previous little-endian mode */ 687 if (sig) 688 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE); 689 690 /* 691 * Do this before updating the thread state in 692 * current->thread.fpr/vr/evr. That way, if we get preempted 693 * and another task grabs the FPU/Altivec/SPE, it won't be 694 * tempted to save the current CPU state into the thread_struct 695 * and corrupt what we are writing there. 696 */ 697 discard_lazy_cpu_state(); 698 699 #ifdef CONFIG_ALTIVEC 700 /* 701 * Force the process to reload the altivec registers from 702 * current->thread when it next does altivec instructions 703 */ 704 regs->msr &= ~MSR_VEC; 705 if (msr & MSR_VEC) { 706 /* restore altivec registers from the stack */ 707 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs, 708 sizeof(sr->mc_vregs))) 709 return 1; 710 } else if (current->thread.used_vr) 711 memset(¤t->thread.vr_state, 0, 712 ELF_NVRREG * sizeof(vector128)); 713 714 /* Always get VRSAVE back */ 715 if (__get_user(current->thread.vrsave, (u32 __user *)&sr->mc_vregs[32])) 716 return 1; 717 if (cpu_has_feature(CPU_FTR_ALTIVEC)) 718 mtspr(SPRN_VRSAVE, current->thread.vrsave); 719 #endif /* CONFIG_ALTIVEC */ 720 if (copy_fpr_from_user(current, &sr->mc_fregs)) 721 return 1; 722 723 #ifdef CONFIG_VSX 724 /* 725 * Force the process to reload the VSX registers from 726 * current->thread when it next does VSX instruction. 727 */ 728 regs->msr &= ~MSR_VSX; 729 if (msr & MSR_VSX) { 730 /* 731 * Restore altivec registers from the stack to a local 732 * buffer, then write this out to the thread_struct 733 */ 734 if (copy_vsx_from_user(current, &sr->mc_vsregs)) 735 return 1; 736 } else if (current->thread.used_vsr) 737 for (i = 0; i < 32 ; i++) 738 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0; 739 #endif /* CONFIG_VSX */ 740 /* 741 * force the process to reload the FP registers from 742 * current->thread when it next does FP instructions 743 */ 744 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1); 745 746 #ifdef CONFIG_SPE 747 /* force the process to reload the spe registers from 748 current->thread when it next does spe instructions */ 749 regs->msr &= ~MSR_SPE; 750 if (msr & MSR_SPE) { 751 /* restore spe registers from the stack */ 752 if (__copy_from_user(current->thread.evr, &sr->mc_vregs, 753 ELF_NEVRREG * sizeof(u32))) 754 return 1; 755 } else if (current->thread.used_spe) 756 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32)); 757 758 /* Always get SPEFSCR back */ 759 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs + ELF_NEVRREG)) 760 return 1; 761 #endif /* CONFIG_SPE */ 762 763 return 0; 764 } 765 766 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 767 /* 768 * Restore the current user register values from the user stack, except for 769 * MSR, and recheckpoint the original checkpointed register state for processes 770 * in transactions. 771 */ 772 static long restore_tm_user_regs(struct pt_regs *regs, 773 struct mcontext __user *sr, 774 struct mcontext __user *tm_sr) 775 { 776 long err; 777 unsigned long msr, msr_hi; 778 #ifdef CONFIG_VSX 779 int i; 780 #endif 781 782 /* 783 * restore general registers but not including MSR or SOFTE. Also 784 * take care of keeping r2 (TLS) intact if not a signal. 785 * See comment in signal_64.c:restore_tm_sigcontexts(); 786 * TFHAR is restored from the checkpointed NIP; TEXASR and TFIAR 787 * were set by the signal delivery. 788 */ 789 err = restore_general_regs(regs, tm_sr); 790 err |= restore_general_regs(¤t->thread.ckpt_regs, sr); 791 792 err |= __get_user(current->thread.tm_tfhar, &sr->mc_gregs[PT_NIP]); 793 794 err |= __get_user(msr, &sr->mc_gregs[PT_MSR]); 795 if (err) 796 return 1; 797 798 /* Restore the previous little-endian mode */ 799 regs->msr = (regs->msr & ~MSR_LE) | (msr & MSR_LE); 800 801 /* 802 * Do this before updating the thread state in 803 * current->thread.fpr/vr/evr. That way, if we get preempted 804 * and another task grabs the FPU/Altivec/SPE, it won't be 805 * tempted to save the current CPU state into the thread_struct 806 * and corrupt what we are writing there. 807 */ 808 discard_lazy_cpu_state(); 809 810 #ifdef CONFIG_ALTIVEC 811 regs->msr &= ~MSR_VEC; 812 if (msr & MSR_VEC) { 813 /* restore altivec registers from the stack */ 814 if (__copy_from_user(¤t->thread.vr_state, &sr->mc_vregs, 815 sizeof(sr->mc_vregs)) || 816 __copy_from_user(¤t->thread.transact_vr, 817 &tm_sr->mc_vregs, 818 sizeof(sr->mc_vregs))) 819 return 1; 820 } else if (current->thread.used_vr) { 821 memset(¤t->thread.vr_state, 0, 822 ELF_NVRREG * sizeof(vector128)); 823 memset(¤t->thread.transact_vr, 0, 824 ELF_NVRREG * sizeof(vector128)); 825 } 826 827 /* Always get VRSAVE back */ 828 if (__get_user(current->thread.vrsave, 829 (u32 __user *)&sr->mc_vregs[32]) || 830 __get_user(current->thread.transact_vrsave, 831 (u32 __user *)&tm_sr->mc_vregs[32])) 832 return 1; 833 if (cpu_has_feature(CPU_FTR_ALTIVEC)) 834 mtspr(SPRN_VRSAVE, current->thread.vrsave); 835 #endif /* CONFIG_ALTIVEC */ 836 837 regs->msr &= ~(MSR_FP | MSR_FE0 | MSR_FE1); 838 839 if (copy_fpr_from_user(current, &sr->mc_fregs) || 840 copy_transact_fpr_from_user(current, &tm_sr->mc_fregs)) 841 return 1; 842 843 #ifdef CONFIG_VSX 844 regs->msr &= ~MSR_VSX; 845 if (msr & MSR_VSX) { 846 /* 847 * Restore altivec registers from the stack to a local 848 * buffer, then write this out to the thread_struct 849 */ 850 if (copy_vsx_from_user(current, &sr->mc_vsregs) || 851 copy_transact_vsx_from_user(current, &tm_sr->mc_vsregs)) 852 return 1; 853 } else if (current->thread.used_vsr) 854 for (i = 0; i < 32 ; i++) { 855 current->thread.fp_state.fpr[i][TS_VSRLOWOFFSET] = 0; 856 current->thread.transact_fp.fpr[i][TS_VSRLOWOFFSET] = 0; 857 } 858 #endif /* CONFIG_VSX */ 859 860 #ifdef CONFIG_SPE 861 /* SPE regs are not checkpointed with TM, so this section is 862 * simply the same as in restore_user_regs(). 863 */ 864 regs->msr &= ~MSR_SPE; 865 if (msr & MSR_SPE) { 866 if (__copy_from_user(current->thread.evr, &sr->mc_vregs, 867 ELF_NEVRREG * sizeof(u32))) 868 return 1; 869 } else if (current->thread.used_spe) 870 memset(current->thread.evr, 0, ELF_NEVRREG * sizeof(u32)); 871 872 /* Always get SPEFSCR back */ 873 if (__get_user(current->thread.spefscr, (u32 __user *)&sr->mc_vregs 874 + ELF_NEVRREG)) 875 return 1; 876 #endif /* CONFIG_SPE */ 877 878 /* Now, recheckpoint. This loads up all of the checkpointed (older) 879 * registers, including FP and V[S]Rs. After recheckpointing, the 880 * transactional versions should be loaded. 881 */ 882 tm_enable(); 883 /* Make sure the transaction is marked as failed */ 884 current->thread.tm_texasr |= TEXASR_FS; 885 /* This loads the checkpointed FP/VEC state, if used */ 886 tm_recheckpoint(¤t->thread, msr); 887 /* Get the top half of the MSR */ 888 if (__get_user(msr_hi, &tm_sr->mc_gregs[PT_MSR])) 889 return 1; 890 /* Pull in MSR TM from user context */ 891 regs->msr = (regs->msr & ~MSR_TS_MASK) | ((msr_hi<<32) & MSR_TS_MASK); 892 893 /* This loads the speculative FP/VEC state, if used */ 894 if (msr & MSR_FP) { 895 do_load_up_transact_fpu(¤t->thread); 896 regs->msr |= (MSR_FP | current->thread.fpexc_mode); 897 } 898 #ifdef CONFIG_ALTIVEC 899 if (msr & MSR_VEC) { 900 do_load_up_transact_altivec(¤t->thread); 901 regs->msr |= MSR_VEC; 902 } 903 #endif 904 905 return 0; 906 } 907 #endif 908 909 #ifdef CONFIG_PPC64 910 int copy_siginfo_to_user32(struct compat_siginfo __user *d, const siginfo_t *s) 911 { 912 int err; 913 914 if (!access_ok (VERIFY_WRITE, d, sizeof(*d))) 915 return -EFAULT; 916 917 /* If you change siginfo_t structure, please be sure 918 * this code is fixed accordingly. 919 * It should never copy any pad contained in the structure 920 * to avoid security leaks, but must copy the generic 921 * 3 ints plus the relevant union member. 922 * This routine must convert siginfo from 64bit to 32bit as well 923 * at the same time. 924 */ 925 err = __put_user(s->si_signo, &d->si_signo); 926 err |= __put_user(s->si_errno, &d->si_errno); 927 err |= __put_user((short)s->si_code, &d->si_code); 928 if (s->si_code < 0) 929 err |= __copy_to_user(&d->_sifields._pad, &s->_sifields._pad, 930 SI_PAD_SIZE32); 931 else switch(s->si_code >> 16) { 932 case __SI_CHLD >> 16: 933 err |= __put_user(s->si_pid, &d->si_pid); 934 err |= __put_user(s->si_uid, &d->si_uid); 935 err |= __put_user(s->si_utime, &d->si_utime); 936 err |= __put_user(s->si_stime, &d->si_stime); 937 err |= __put_user(s->si_status, &d->si_status); 938 break; 939 case __SI_FAULT >> 16: 940 err |= __put_user((unsigned int)(unsigned long)s->si_addr, 941 &d->si_addr); 942 break; 943 case __SI_POLL >> 16: 944 err |= __put_user(s->si_band, &d->si_band); 945 err |= __put_user(s->si_fd, &d->si_fd); 946 break; 947 case __SI_TIMER >> 16: 948 err |= __put_user(s->si_tid, &d->si_tid); 949 err |= __put_user(s->si_overrun, &d->si_overrun); 950 err |= __put_user(s->si_int, &d->si_int); 951 break; 952 case __SI_RT >> 16: /* This is not generated by the kernel as of now. */ 953 case __SI_MESGQ >> 16: 954 err |= __put_user(s->si_int, &d->si_int); 955 /* fallthrough */ 956 case __SI_KILL >> 16: 957 default: 958 err |= __put_user(s->si_pid, &d->si_pid); 959 err |= __put_user(s->si_uid, &d->si_uid); 960 break; 961 } 962 return err; 963 } 964 965 #define copy_siginfo_to_user copy_siginfo_to_user32 966 967 int copy_siginfo_from_user32(siginfo_t *to, struct compat_siginfo __user *from) 968 { 969 memset(to, 0, sizeof *to); 970 971 if (copy_from_user(to, from, 3*sizeof(int)) || 972 copy_from_user(to->_sifields._pad, 973 from->_sifields._pad, SI_PAD_SIZE32)) 974 return -EFAULT; 975 976 return 0; 977 } 978 #endif /* CONFIG_PPC64 */ 979 980 /* 981 * Set up a signal frame for a "real-time" signal handler 982 * (one which gets siginfo). 983 */ 984 int handle_rt_signal32(struct ksignal *ksig, sigset_t *oldset, 985 struct pt_regs *regs) 986 { 987 struct rt_sigframe __user *rt_sf; 988 struct mcontext __user *frame; 989 struct mcontext __user *tm_frame = NULL; 990 void __user *addr; 991 unsigned long newsp = 0; 992 int sigret; 993 unsigned long tramp; 994 995 /* Set up Signal Frame */ 996 /* Put a Real Time Context onto stack */ 997 rt_sf = get_sigframe(ksig, get_tm_stackpointer(regs), sizeof(*rt_sf), 1); 998 addr = rt_sf; 999 if (unlikely(rt_sf == NULL)) 1000 goto badframe; 1001 1002 /* Put the siginfo & fill in most of the ucontext */ 1003 if (copy_siginfo_to_user(&rt_sf->info, &ksig->info) 1004 || __put_user(0, &rt_sf->uc.uc_flags) 1005 || __save_altstack(&rt_sf->uc.uc_stack, regs->gpr[1]) 1006 || __put_user(to_user_ptr(&rt_sf->uc.uc_mcontext), 1007 &rt_sf->uc.uc_regs) 1008 || put_sigset_t(&rt_sf->uc.uc_sigmask, oldset)) 1009 goto badframe; 1010 1011 /* Save user registers on the stack */ 1012 frame = &rt_sf->uc.uc_mcontext; 1013 addr = frame; 1014 if (vdso32_rt_sigtramp && current->mm->context.vdso_base) { 1015 sigret = 0; 1016 tramp = current->mm->context.vdso_base + vdso32_rt_sigtramp; 1017 } else { 1018 sigret = __NR_rt_sigreturn; 1019 tramp = (unsigned long) frame->tramp; 1020 } 1021 1022 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1023 tm_frame = &rt_sf->uc_transact.uc_mcontext; 1024 if (MSR_TM_ACTIVE(regs->msr)) { 1025 if (__put_user((unsigned long)&rt_sf->uc_transact, 1026 &rt_sf->uc.uc_link) || 1027 __put_user((unsigned long)tm_frame, 1028 &rt_sf->uc_transact.uc_regs)) 1029 goto badframe; 1030 if (save_tm_user_regs(regs, frame, tm_frame, sigret)) 1031 goto badframe; 1032 } 1033 else 1034 #endif 1035 { 1036 if (__put_user(0, &rt_sf->uc.uc_link)) 1037 goto badframe; 1038 if (save_user_regs(regs, frame, tm_frame, sigret, 1)) 1039 goto badframe; 1040 } 1041 regs->link = tramp; 1042 1043 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */ 1044 1045 /* create a stack frame for the caller of the handler */ 1046 newsp = ((unsigned long)rt_sf) - (__SIGNAL_FRAMESIZE + 16); 1047 addr = (void __user *)regs->gpr[1]; 1048 if (put_user(regs->gpr[1], (u32 __user *)newsp)) 1049 goto badframe; 1050 1051 /* Fill registers for signal handler */ 1052 regs->gpr[1] = newsp; 1053 regs->gpr[3] = ksig->sig; 1054 regs->gpr[4] = (unsigned long) &rt_sf->info; 1055 regs->gpr[5] = (unsigned long) &rt_sf->uc; 1056 regs->gpr[6] = (unsigned long) rt_sf; 1057 regs->nip = (unsigned long) ksig->ka.sa.sa_handler; 1058 /* enter the signal handler in native-endian mode */ 1059 regs->msr &= ~MSR_LE; 1060 regs->msr |= (MSR_KERNEL & MSR_LE); 1061 return 0; 1062 1063 badframe: 1064 if (show_unhandled_signals) 1065 printk_ratelimited(KERN_INFO 1066 "%s[%d]: bad frame in handle_rt_signal32: " 1067 "%p nip %08lx lr %08lx\n", 1068 current->comm, current->pid, 1069 addr, regs->nip, regs->link); 1070 1071 return 1; 1072 } 1073 1074 static int do_setcontext(struct ucontext __user *ucp, struct pt_regs *regs, int sig) 1075 { 1076 sigset_t set; 1077 struct mcontext __user *mcp; 1078 1079 if (get_sigset_t(&set, &ucp->uc_sigmask)) 1080 return -EFAULT; 1081 #ifdef CONFIG_PPC64 1082 { 1083 u32 cmcp; 1084 1085 if (__get_user(cmcp, &ucp->uc_regs)) 1086 return -EFAULT; 1087 mcp = (struct mcontext __user *)(u64)cmcp; 1088 /* no need to check access_ok(mcp), since mcp < 4GB */ 1089 } 1090 #else 1091 if (__get_user(mcp, &ucp->uc_regs)) 1092 return -EFAULT; 1093 if (!access_ok(VERIFY_READ, mcp, sizeof(*mcp))) 1094 return -EFAULT; 1095 #endif 1096 set_current_blocked(&set); 1097 if (restore_user_regs(regs, mcp, sig)) 1098 return -EFAULT; 1099 1100 return 0; 1101 } 1102 1103 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1104 static int do_setcontext_tm(struct ucontext __user *ucp, 1105 struct ucontext __user *tm_ucp, 1106 struct pt_regs *regs) 1107 { 1108 sigset_t set; 1109 struct mcontext __user *mcp; 1110 struct mcontext __user *tm_mcp; 1111 u32 cmcp; 1112 u32 tm_cmcp; 1113 1114 if (get_sigset_t(&set, &ucp->uc_sigmask)) 1115 return -EFAULT; 1116 1117 if (__get_user(cmcp, &ucp->uc_regs) || 1118 __get_user(tm_cmcp, &tm_ucp->uc_regs)) 1119 return -EFAULT; 1120 mcp = (struct mcontext __user *)(u64)cmcp; 1121 tm_mcp = (struct mcontext __user *)(u64)tm_cmcp; 1122 /* no need to check access_ok(mcp), since mcp < 4GB */ 1123 1124 set_current_blocked(&set); 1125 if (restore_tm_user_regs(regs, mcp, tm_mcp)) 1126 return -EFAULT; 1127 1128 return 0; 1129 } 1130 #endif 1131 1132 long sys_swapcontext(struct ucontext __user *old_ctx, 1133 struct ucontext __user *new_ctx, 1134 int ctx_size, int r6, int r7, int r8, struct pt_regs *regs) 1135 { 1136 unsigned char tmp; 1137 int ctx_has_vsx_region = 0; 1138 1139 #ifdef CONFIG_PPC64 1140 unsigned long new_msr = 0; 1141 1142 if (new_ctx) { 1143 struct mcontext __user *mcp; 1144 u32 cmcp; 1145 1146 /* 1147 * Get pointer to the real mcontext. No need for 1148 * access_ok since we are dealing with compat 1149 * pointers. 1150 */ 1151 if (__get_user(cmcp, &new_ctx->uc_regs)) 1152 return -EFAULT; 1153 mcp = (struct mcontext __user *)(u64)cmcp; 1154 if (__get_user(new_msr, &mcp->mc_gregs[PT_MSR])) 1155 return -EFAULT; 1156 } 1157 /* 1158 * Check that the context is not smaller than the original 1159 * size (with VMX but without VSX) 1160 */ 1161 if (ctx_size < UCONTEXTSIZEWITHOUTVSX) 1162 return -EINVAL; 1163 /* 1164 * If the new context state sets the MSR VSX bits but 1165 * it doesn't provide VSX state. 1166 */ 1167 if ((ctx_size < sizeof(struct ucontext)) && 1168 (new_msr & MSR_VSX)) 1169 return -EINVAL; 1170 /* Does the context have enough room to store VSX data? */ 1171 if (ctx_size >= sizeof(struct ucontext)) 1172 ctx_has_vsx_region = 1; 1173 #else 1174 /* Context size is for future use. Right now, we only make sure 1175 * we are passed something we understand 1176 */ 1177 if (ctx_size < sizeof(struct ucontext)) 1178 return -EINVAL; 1179 #endif 1180 if (old_ctx != NULL) { 1181 struct mcontext __user *mctx; 1182 1183 /* 1184 * old_ctx might not be 16-byte aligned, in which 1185 * case old_ctx->uc_mcontext won't be either. 1186 * Because we have the old_ctx->uc_pad2 field 1187 * before old_ctx->uc_mcontext, we need to round down 1188 * from &old_ctx->uc_mcontext to a 16-byte boundary. 1189 */ 1190 mctx = (struct mcontext __user *) 1191 ((unsigned long) &old_ctx->uc_mcontext & ~0xfUL); 1192 if (!access_ok(VERIFY_WRITE, old_ctx, ctx_size) 1193 || save_user_regs(regs, mctx, NULL, 0, ctx_has_vsx_region) 1194 || put_sigset_t(&old_ctx->uc_sigmask, ¤t->blocked) 1195 || __put_user(to_user_ptr(mctx), &old_ctx->uc_regs)) 1196 return -EFAULT; 1197 } 1198 if (new_ctx == NULL) 1199 return 0; 1200 if (!access_ok(VERIFY_READ, new_ctx, ctx_size) 1201 || __get_user(tmp, (u8 __user *) new_ctx) 1202 || __get_user(tmp, (u8 __user *) new_ctx + ctx_size - 1)) 1203 return -EFAULT; 1204 1205 /* 1206 * If we get a fault copying the context into the kernel's 1207 * image of the user's registers, we can't just return -EFAULT 1208 * because the user's registers will be corrupted. For instance 1209 * the NIP value may have been updated but not some of the 1210 * other registers. Given that we have done the access_ok 1211 * and successfully read the first and last bytes of the region 1212 * above, this should only happen in an out-of-memory situation 1213 * or if another thread unmaps the region containing the context. 1214 * We kill the task with a SIGSEGV in this situation. 1215 */ 1216 if (do_setcontext(new_ctx, regs, 0)) 1217 do_exit(SIGSEGV); 1218 1219 set_thread_flag(TIF_RESTOREALL); 1220 return 0; 1221 } 1222 1223 long sys_rt_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, 1224 struct pt_regs *regs) 1225 { 1226 struct rt_sigframe __user *rt_sf; 1227 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1228 struct ucontext __user *uc_transact; 1229 unsigned long msr_hi; 1230 unsigned long tmp; 1231 int tm_restore = 0; 1232 #endif 1233 /* Always make any pending restarted system calls return -EINTR */ 1234 current_thread_info()->restart_block.fn = do_no_restart_syscall; 1235 1236 rt_sf = (struct rt_sigframe __user *) 1237 (regs->gpr[1] + __SIGNAL_FRAMESIZE + 16); 1238 if (!access_ok(VERIFY_READ, rt_sf, sizeof(*rt_sf))) 1239 goto bad; 1240 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1241 if (__get_user(tmp, &rt_sf->uc.uc_link)) 1242 goto bad; 1243 uc_transact = (struct ucontext __user *)(uintptr_t)tmp; 1244 if (uc_transact) { 1245 u32 cmcp; 1246 struct mcontext __user *mcp; 1247 1248 if (__get_user(cmcp, &uc_transact->uc_regs)) 1249 return -EFAULT; 1250 mcp = (struct mcontext __user *)(u64)cmcp; 1251 /* The top 32 bits of the MSR are stashed in the transactional 1252 * ucontext. */ 1253 if (__get_user(msr_hi, &mcp->mc_gregs[PT_MSR])) 1254 goto bad; 1255 1256 if (MSR_TM_ACTIVE(msr_hi<<32)) { 1257 /* We only recheckpoint on return if we're 1258 * transaction. 1259 */ 1260 tm_restore = 1; 1261 if (do_setcontext_tm(&rt_sf->uc, uc_transact, regs)) 1262 goto bad; 1263 } 1264 } 1265 if (!tm_restore) 1266 /* Fall through, for non-TM restore */ 1267 #endif 1268 if (do_setcontext(&rt_sf->uc, regs, 1)) 1269 goto bad; 1270 1271 /* 1272 * It's not clear whether or why it is desirable to save the 1273 * sigaltstack setting on signal delivery and restore it on 1274 * signal return. But other architectures do this and we have 1275 * always done it up until now so it is probably better not to 1276 * change it. -- paulus 1277 */ 1278 #ifdef CONFIG_PPC64 1279 if (compat_restore_altstack(&rt_sf->uc.uc_stack)) 1280 goto bad; 1281 #else 1282 if (restore_altstack(&rt_sf->uc.uc_stack)) 1283 goto bad; 1284 #endif 1285 set_thread_flag(TIF_RESTOREALL); 1286 return 0; 1287 1288 bad: 1289 if (show_unhandled_signals) 1290 printk_ratelimited(KERN_INFO 1291 "%s[%d]: bad frame in sys_rt_sigreturn: " 1292 "%p nip %08lx lr %08lx\n", 1293 current->comm, current->pid, 1294 rt_sf, regs->nip, regs->link); 1295 1296 force_sig(SIGSEGV, current); 1297 return 0; 1298 } 1299 1300 #ifdef CONFIG_PPC32 1301 int sys_debug_setcontext(struct ucontext __user *ctx, 1302 int ndbg, struct sig_dbg_op __user *dbg, 1303 int r6, int r7, int r8, 1304 struct pt_regs *regs) 1305 { 1306 struct sig_dbg_op op; 1307 int i; 1308 unsigned char tmp; 1309 unsigned long new_msr = regs->msr; 1310 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 1311 unsigned long new_dbcr0 = current->thread.debug.dbcr0; 1312 #endif 1313 1314 for (i=0; i<ndbg; i++) { 1315 if (copy_from_user(&op, dbg + i, sizeof(op))) 1316 return -EFAULT; 1317 switch (op.dbg_type) { 1318 case SIG_DBG_SINGLE_STEPPING: 1319 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 1320 if (op.dbg_value) { 1321 new_msr |= MSR_DE; 1322 new_dbcr0 |= (DBCR0_IDM | DBCR0_IC); 1323 } else { 1324 new_dbcr0 &= ~DBCR0_IC; 1325 if (!DBCR_ACTIVE_EVENTS(new_dbcr0, 1326 current->thread.debug.dbcr1)) { 1327 new_msr &= ~MSR_DE; 1328 new_dbcr0 &= ~DBCR0_IDM; 1329 } 1330 } 1331 #else 1332 if (op.dbg_value) 1333 new_msr |= MSR_SE; 1334 else 1335 new_msr &= ~MSR_SE; 1336 #endif 1337 break; 1338 case SIG_DBG_BRANCH_TRACING: 1339 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 1340 return -EINVAL; 1341 #else 1342 if (op.dbg_value) 1343 new_msr |= MSR_BE; 1344 else 1345 new_msr &= ~MSR_BE; 1346 #endif 1347 break; 1348 1349 default: 1350 return -EINVAL; 1351 } 1352 } 1353 1354 /* We wait until here to actually install the values in the 1355 registers so if we fail in the above loop, it will not 1356 affect the contents of these registers. After this point, 1357 failure is a problem, anyway, and it's very unlikely unless 1358 the user is really doing something wrong. */ 1359 regs->msr = new_msr; 1360 #ifdef CONFIG_PPC_ADV_DEBUG_REGS 1361 current->thread.debug.dbcr0 = new_dbcr0; 1362 #endif 1363 1364 if (!access_ok(VERIFY_READ, ctx, sizeof(*ctx)) 1365 || __get_user(tmp, (u8 __user *) ctx) 1366 || __get_user(tmp, (u8 __user *) (ctx + 1) - 1)) 1367 return -EFAULT; 1368 1369 /* 1370 * If we get a fault copying the context into the kernel's 1371 * image of the user's registers, we can't just return -EFAULT 1372 * because the user's registers will be corrupted. For instance 1373 * the NIP value may have been updated but not some of the 1374 * other registers. Given that we have done the access_ok 1375 * and successfully read the first and last bytes of the region 1376 * above, this should only happen in an out-of-memory situation 1377 * or if another thread unmaps the region containing the context. 1378 * We kill the task with a SIGSEGV in this situation. 1379 */ 1380 if (do_setcontext(ctx, regs, 1)) { 1381 if (show_unhandled_signals) 1382 printk_ratelimited(KERN_INFO "%s[%d]: bad frame in " 1383 "sys_debug_setcontext: %p nip %08lx " 1384 "lr %08lx\n", 1385 current->comm, current->pid, 1386 ctx, regs->nip, regs->link); 1387 1388 force_sig(SIGSEGV, current); 1389 goto out; 1390 } 1391 1392 /* 1393 * It's not clear whether or why it is desirable to save the 1394 * sigaltstack setting on signal delivery and restore it on 1395 * signal return. But other architectures do this and we have 1396 * always done it up until now so it is probably better not to 1397 * change it. -- paulus 1398 */ 1399 restore_altstack(&ctx->uc_stack); 1400 1401 set_thread_flag(TIF_RESTOREALL); 1402 out: 1403 return 0; 1404 } 1405 #endif 1406 1407 /* 1408 * OK, we're invoking a handler 1409 */ 1410 int handle_signal32(struct ksignal *ksig, sigset_t *oldset, struct pt_regs *regs) 1411 { 1412 struct sigcontext __user *sc; 1413 struct sigframe __user *frame; 1414 struct mcontext __user *tm_mctx = NULL; 1415 unsigned long newsp = 0; 1416 int sigret; 1417 unsigned long tramp; 1418 1419 /* Set up Signal Frame */ 1420 frame = get_sigframe(ksig, get_tm_stackpointer(regs), sizeof(*frame), 1); 1421 if (unlikely(frame == NULL)) 1422 goto badframe; 1423 sc = (struct sigcontext __user *) &frame->sctx; 1424 1425 #if _NSIG != 64 1426 #error "Please adjust handle_signal()" 1427 #endif 1428 if (__put_user(to_user_ptr(ksig->ka.sa.sa_handler), &sc->handler) 1429 || __put_user(oldset->sig[0], &sc->oldmask) 1430 #ifdef CONFIG_PPC64 1431 || __put_user((oldset->sig[0] >> 32), &sc->_unused[3]) 1432 #else 1433 || __put_user(oldset->sig[1], &sc->_unused[3]) 1434 #endif 1435 || __put_user(to_user_ptr(&frame->mctx), &sc->regs) 1436 || __put_user(ksig->sig, &sc->signal)) 1437 goto badframe; 1438 1439 if (vdso32_sigtramp && current->mm->context.vdso_base) { 1440 sigret = 0; 1441 tramp = current->mm->context.vdso_base + vdso32_sigtramp; 1442 } else { 1443 sigret = __NR_sigreturn; 1444 tramp = (unsigned long) frame->mctx.tramp; 1445 } 1446 1447 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1448 tm_mctx = &frame->mctx_transact; 1449 if (MSR_TM_ACTIVE(regs->msr)) { 1450 if (save_tm_user_regs(regs, &frame->mctx, &frame->mctx_transact, 1451 sigret)) 1452 goto badframe; 1453 } 1454 else 1455 #endif 1456 { 1457 if (save_user_regs(regs, &frame->mctx, tm_mctx, sigret, 1)) 1458 goto badframe; 1459 } 1460 1461 regs->link = tramp; 1462 1463 current->thread.fp_state.fpscr = 0; /* turn off all fp exceptions */ 1464 1465 /* create a stack frame for the caller of the handler */ 1466 newsp = ((unsigned long)frame) - __SIGNAL_FRAMESIZE; 1467 if (put_user(regs->gpr[1], (u32 __user *)newsp)) 1468 goto badframe; 1469 1470 regs->gpr[1] = newsp; 1471 regs->gpr[3] = ksig->sig; 1472 regs->gpr[4] = (unsigned long) sc; 1473 regs->nip = (unsigned long) (unsigned long)ksig->ka.sa.sa_handler; 1474 /* enter the signal handler in big-endian mode */ 1475 regs->msr &= ~MSR_LE; 1476 return 0; 1477 1478 badframe: 1479 if (show_unhandled_signals) 1480 printk_ratelimited(KERN_INFO 1481 "%s[%d]: bad frame in handle_signal32: " 1482 "%p nip %08lx lr %08lx\n", 1483 current->comm, current->pid, 1484 frame, regs->nip, regs->link); 1485 1486 return 1; 1487 } 1488 1489 /* 1490 * Do a signal return; undo the signal stack. 1491 */ 1492 long sys_sigreturn(int r3, int r4, int r5, int r6, int r7, int r8, 1493 struct pt_regs *regs) 1494 { 1495 struct sigframe __user *sf; 1496 struct sigcontext __user *sc; 1497 struct sigcontext sigctx; 1498 struct mcontext __user *sr; 1499 void __user *addr; 1500 sigset_t set; 1501 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1502 struct mcontext __user *mcp, *tm_mcp; 1503 unsigned long msr_hi; 1504 #endif 1505 1506 /* Always make any pending restarted system calls return -EINTR */ 1507 current_thread_info()->restart_block.fn = do_no_restart_syscall; 1508 1509 sf = (struct sigframe __user *)(regs->gpr[1] + __SIGNAL_FRAMESIZE); 1510 sc = &sf->sctx; 1511 addr = sc; 1512 if (copy_from_user(&sigctx, sc, sizeof(sigctx))) 1513 goto badframe; 1514 1515 #ifdef CONFIG_PPC64 1516 /* 1517 * Note that PPC32 puts the upper 32 bits of the sigmask in the 1518 * unused part of the signal stackframe 1519 */ 1520 set.sig[0] = sigctx.oldmask + ((long)(sigctx._unused[3]) << 32); 1521 #else 1522 set.sig[0] = sigctx.oldmask; 1523 set.sig[1] = sigctx._unused[3]; 1524 #endif 1525 set_current_blocked(&set); 1526 1527 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 1528 mcp = (struct mcontext __user *)&sf->mctx; 1529 tm_mcp = (struct mcontext __user *)&sf->mctx_transact; 1530 if (__get_user(msr_hi, &tm_mcp->mc_gregs[PT_MSR])) 1531 goto badframe; 1532 if (MSR_TM_ACTIVE(msr_hi<<32)) { 1533 if (!cpu_has_feature(CPU_FTR_TM)) 1534 goto badframe; 1535 if (restore_tm_user_regs(regs, mcp, tm_mcp)) 1536 goto badframe; 1537 } else 1538 #endif 1539 { 1540 sr = (struct mcontext __user *)from_user_ptr(sigctx.regs); 1541 addr = sr; 1542 if (!access_ok(VERIFY_READ, sr, sizeof(*sr)) 1543 || restore_user_regs(regs, sr, 1)) 1544 goto badframe; 1545 } 1546 1547 set_thread_flag(TIF_RESTOREALL); 1548 return 0; 1549 1550 badframe: 1551 if (show_unhandled_signals) 1552 printk_ratelimited(KERN_INFO 1553 "%s[%d]: bad frame in sys_sigreturn: " 1554 "%p nip %08lx lr %08lx\n", 1555 current->comm, current->pid, 1556 addr, regs->nip, regs->link); 1557 1558 force_sig(SIGSEGV, current); 1559 return 0; 1560 } 1561