1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Kernel support for the ptrace() and syscall tracing interfaces. 4 * 5 * Copyright (C) 2000 Hewlett-Packard Co, Linuxcare Inc. 6 * Copyright (C) 2000 Matthew Wilcox <matthew@wil.cx> 7 * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org> 8 * Copyright (C) 2008-2016 Helge Deller <deller@gmx.de> 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/sched.h> 13 #include <linux/mm.h> 14 #include <linux/smp.h> 15 #include <linux/elf.h> 16 #include <linux/errno.h> 17 #include <linux/ptrace.h> 18 #include <linux/user.h> 19 #include <linux/personality.h> 20 #include <linux/regset.h> 21 #include <linux/security.h> 22 #include <linux/seccomp.h> 23 #include <linux/compat.h> 24 #include <linux/signal.h> 25 #include <linux/audit.h> 26 27 #include <linux/uaccess.h> 28 #include <asm/processor.h> 29 #include <asm/asm-offsets.h> 30 31 /* PSW bits we allow the debugger to modify */ 32 #define USER_PSW_BITS (PSW_N | PSW_B | PSW_V | PSW_CB) 33 34 #define CREATE_TRACE_POINTS 35 #include <trace/events/syscalls.h> 36 37 /* 38 * These are our native regset flavors. 39 */ 40 enum parisc_regset { 41 REGSET_GENERAL, 42 REGSET_FP 43 }; 44 45 /* 46 * Called by kernel/ptrace.c when detaching.. 47 * 48 * Make sure single step bits etc are not set. 49 */ 50 void ptrace_disable(struct task_struct *task) 51 { 52 clear_tsk_thread_flag(task, TIF_SINGLESTEP); 53 clear_tsk_thread_flag(task, TIF_BLOCKSTEP); 54 55 /* make sure the trap bits are not set */ 56 pa_psw(task)->r = 0; 57 pa_psw(task)->t = 0; 58 pa_psw(task)->h = 0; 59 pa_psw(task)->l = 0; 60 } 61 62 /* 63 * The following functions are called by ptrace_resume() when 64 * enabling or disabling single/block tracing. 65 */ 66 void user_disable_single_step(struct task_struct *task) 67 { 68 ptrace_disable(task); 69 } 70 71 void user_enable_single_step(struct task_struct *task) 72 { 73 clear_tsk_thread_flag(task, TIF_BLOCKSTEP); 74 set_tsk_thread_flag(task, TIF_SINGLESTEP); 75 76 if (pa_psw(task)->n) { 77 /* Nullified, just crank over the queue. */ 78 task_regs(task)->iaoq[0] = task_regs(task)->iaoq[1]; 79 task_regs(task)->iasq[0] = task_regs(task)->iasq[1]; 80 task_regs(task)->iaoq[1] = task_regs(task)->iaoq[0] + 4; 81 pa_psw(task)->n = 0; 82 pa_psw(task)->x = 0; 83 pa_psw(task)->y = 0; 84 pa_psw(task)->z = 0; 85 pa_psw(task)->b = 0; 86 ptrace_disable(task); 87 /* Don't wake up the task, but let the 88 parent know something happened. */ 89 force_sig_fault_to_task(SIGTRAP, TRAP_TRACE, 90 (void __user *) (task_regs(task)->iaoq[0] & ~3), 91 task); 92 /* notify_parent(task, SIGCHLD); */ 93 return; 94 } 95 96 /* Enable recovery counter traps. The recovery counter 97 * itself will be set to zero on a task switch. If the 98 * task is suspended on a syscall then the syscall return 99 * path will overwrite the recovery counter with a suitable 100 * value such that it traps once back in user space. We 101 * disable interrupts in the tasks PSW here also, to avoid 102 * interrupts while the recovery counter is decrementing. 103 */ 104 pa_psw(task)->r = 1; 105 pa_psw(task)->t = 0; 106 pa_psw(task)->h = 0; 107 pa_psw(task)->l = 0; 108 } 109 110 void user_enable_block_step(struct task_struct *task) 111 { 112 clear_tsk_thread_flag(task, TIF_SINGLESTEP); 113 set_tsk_thread_flag(task, TIF_BLOCKSTEP); 114 115 /* Enable taken branch trap. */ 116 pa_psw(task)->r = 0; 117 pa_psw(task)->t = 1; 118 pa_psw(task)->h = 0; 119 pa_psw(task)->l = 0; 120 } 121 122 long arch_ptrace(struct task_struct *child, long request, 123 unsigned long addr, unsigned long data) 124 { 125 unsigned long __user *datap = (unsigned long __user *)data; 126 unsigned long tmp; 127 long ret = -EIO; 128 129 switch (request) { 130 131 /* Read the word at location addr in the USER area. For ptraced 132 processes, the kernel saves all regs on a syscall. */ 133 case PTRACE_PEEKUSR: 134 if ((addr & (sizeof(unsigned long)-1)) || 135 addr >= sizeof(struct pt_regs)) 136 break; 137 tmp = *(unsigned long *) ((char *) task_regs(child) + addr); 138 ret = put_user(tmp, datap); 139 break; 140 141 /* Write the word at location addr in the USER area. This will need 142 to change when the kernel no longer saves all regs on a syscall. 143 FIXME. There is a problem at the moment in that r3-r18 are only 144 saved if the process is ptraced on syscall entry, and even then 145 those values are overwritten by actual register values on syscall 146 exit. */ 147 case PTRACE_POKEUSR: 148 /* Some register values written here may be ignored in 149 * entry.S:syscall_restore_rfi; e.g. iaoq is written with 150 * r31/r31+4, and not with the values in pt_regs. 151 */ 152 if (addr == PT_PSW) { 153 /* Allow writing to Nullify, Divide-step-correction, 154 * and carry/borrow bits. 155 * BEWARE, if you set N, and then single step, it won't 156 * stop on the nullified instruction. 157 */ 158 data &= USER_PSW_BITS; 159 task_regs(child)->gr[0] &= ~USER_PSW_BITS; 160 task_regs(child)->gr[0] |= data; 161 ret = 0; 162 break; 163 } 164 165 if ((addr & (sizeof(unsigned long)-1)) || 166 addr >= sizeof(struct pt_regs)) 167 break; 168 if (addr == PT_IAOQ0 || addr == PT_IAOQ1) { 169 data |= 3; /* ensure userspace privilege */ 170 } 171 if ((addr >= PT_GR1 && addr <= PT_GR31) || 172 addr == PT_IAOQ0 || addr == PT_IAOQ1 || 173 (addr >= PT_FR0 && addr <= PT_FR31 + 4) || 174 addr == PT_SAR) { 175 *(unsigned long *) ((char *) task_regs(child) + addr) = data; 176 ret = 0; 177 } 178 break; 179 180 case PTRACE_GETREGS: /* Get all gp regs from the child. */ 181 return copy_regset_to_user(child, 182 task_user_regset_view(current), 183 REGSET_GENERAL, 184 0, sizeof(struct user_regs_struct), 185 datap); 186 187 case PTRACE_SETREGS: /* Set all gp regs in the child. */ 188 return copy_regset_from_user(child, 189 task_user_regset_view(current), 190 REGSET_GENERAL, 191 0, sizeof(struct user_regs_struct), 192 datap); 193 194 case PTRACE_GETFPREGS: /* Get the child FPU state. */ 195 return copy_regset_to_user(child, 196 task_user_regset_view(current), 197 REGSET_FP, 198 0, sizeof(struct user_fp_struct), 199 datap); 200 201 case PTRACE_SETFPREGS: /* Set the child FPU state. */ 202 return copy_regset_from_user(child, 203 task_user_regset_view(current), 204 REGSET_FP, 205 0, sizeof(struct user_fp_struct), 206 datap); 207 208 default: 209 ret = ptrace_request(child, request, addr, data); 210 break; 211 } 212 213 return ret; 214 } 215 216 217 #ifdef CONFIG_COMPAT 218 219 /* This function is needed to translate 32 bit pt_regs offsets in to 220 * 64 bit pt_regs offsets. For example, a 32 bit gdb under a 64 bit kernel 221 * will request offset 12 if it wants gr3, but the lower 32 bits of 222 * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4). 223 * This code relies on a 32 bit pt_regs being comprised of 32 bit values 224 * except for the fp registers which (a) are 64 bits, and (b) follow 225 * the gr registers at the start of pt_regs. The 32 bit pt_regs should 226 * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[] 227 * being 64 bit in both cases. 228 */ 229 230 static compat_ulong_t translate_usr_offset(compat_ulong_t offset) 231 { 232 compat_ulong_t pos; 233 234 if (offset < 32*4) /* gr[0..31] */ 235 pos = offset * 2 + 4; 236 else if (offset < 32*4+32*8) /* fr[0] ... fr[31] */ 237 pos = (offset - 32*4) + PT_FR0; 238 else if (offset < sizeof(struct pt_regs)/2 + 32*4) /* sr[0] ... ipsw */ 239 pos = (offset - 32*4 - 32*8) * 2 + PT_SR0 + 4; 240 else 241 pos = sizeof(struct pt_regs); 242 243 return pos; 244 } 245 246 long compat_arch_ptrace(struct task_struct *child, compat_long_t request, 247 compat_ulong_t addr, compat_ulong_t data) 248 { 249 compat_uint_t tmp; 250 long ret = -EIO; 251 252 switch (request) { 253 254 case PTRACE_PEEKUSR: 255 if (addr & (sizeof(compat_uint_t)-1)) 256 break; 257 addr = translate_usr_offset(addr); 258 if (addr >= sizeof(struct pt_regs)) 259 break; 260 261 tmp = *(compat_uint_t *) ((char *) task_regs(child) + addr); 262 ret = put_user(tmp, (compat_uint_t *) (unsigned long) data); 263 break; 264 265 /* Write the word at location addr in the USER area. This will need 266 to change when the kernel no longer saves all regs on a syscall. 267 FIXME. There is a problem at the moment in that r3-r18 are only 268 saved if the process is ptraced on syscall entry, and even then 269 those values are overwritten by actual register values on syscall 270 exit. */ 271 case PTRACE_POKEUSR: 272 /* Some register values written here may be ignored in 273 * entry.S:syscall_restore_rfi; e.g. iaoq is written with 274 * r31/r31+4, and not with the values in pt_regs. 275 */ 276 if (addr == PT_PSW) { 277 /* Since PT_PSW==0, it is valid for 32 bit processes 278 * under 64 bit kernels as well. 279 */ 280 ret = arch_ptrace(child, request, addr, data); 281 } else { 282 if (addr & (sizeof(compat_uint_t)-1)) 283 break; 284 addr = translate_usr_offset(addr); 285 if (addr >= sizeof(struct pt_regs)) 286 break; 287 if (addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4) { 288 data |= 3; /* ensure userspace privilege */ 289 } 290 if (addr >= PT_FR0 && addr <= PT_FR31 + 4) { 291 /* Special case, fp regs are 64 bits anyway */ 292 *(__u32 *) ((char *) task_regs(child) + addr) = data; 293 ret = 0; 294 } 295 else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) || 296 addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 || 297 addr == PT_SAR+4) { 298 /* Zero the top 32 bits */ 299 *(__u32 *) ((char *) task_regs(child) + addr - 4) = 0; 300 *(__u32 *) ((char *) task_regs(child) + addr) = data; 301 ret = 0; 302 } 303 } 304 break; 305 306 default: 307 ret = compat_ptrace_request(child, request, addr, data); 308 break; 309 } 310 311 return ret; 312 } 313 #endif 314 315 long do_syscall_trace_enter(struct pt_regs *regs) 316 { 317 if (test_thread_flag(TIF_SYSCALL_TRACE)) { 318 int rc = ptrace_report_syscall_entry(regs); 319 320 /* 321 * As tracesys_next does not set %r28 to -ENOSYS 322 * when %r20 is set to -1, initialize it here. 323 */ 324 regs->gr[28] = -ENOSYS; 325 326 if (rc) { 327 /* 328 * A nonzero return code from 329 * ptrace_report_syscall_entry() tells us 330 * to prevent the syscall execution. Skip 331 * the syscall call and the syscall restart handling. 332 * 333 * Note that the tracer may also just change 334 * regs->gr[20] to an invalid syscall number, 335 * that is handled by tracesys_next. 336 */ 337 regs->gr[20] = -1UL; 338 return -1; 339 } 340 } 341 342 /* Do the secure computing check after ptrace. */ 343 if (secure_computing() == -1) 344 return -1; 345 346 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS 347 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 348 trace_sys_enter(regs, regs->gr[20]); 349 #endif 350 351 #ifdef CONFIG_64BIT 352 if (!is_compat_task()) 353 audit_syscall_entry(regs->gr[20], regs->gr[26], regs->gr[25], 354 regs->gr[24], regs->gr[23]); 355 else 356 #endif 357 audit_syscall_entry(regs->gr[20] & 0xffffffff, 358 regs->gr[26] & 0xffffffff, 359 regs->gr[25] & 0xffffffff, 360 regs->gr[24] & 0xffffffff, 361 regs->gr[23] & 0xffffffff); 362 363 /* 364 * Sign extend the syscall number to 64bit since it may have been 365 * modified by a compat ptrace call 366 */ 367 return (int) ((u32) regs->gr[20]); 368 } 369 370 void do_syscall_trace_exit(struct pt_regs *regs) 371 { 372 int stepping = test_thread_flag(TIF_SINGLESTEP) || 373 test_thread_flag(TIF_BLOCKSTEP); 374 375 audit_syscall_exit(regs); 376 377 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS 378 if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) 379 trace_sys_exit(regs, regs->gr[20]); 380 #endif 381 382 if (stepping || test_thread_flag(TIF_SYSCALL_TRACE)) 383 ptrace_report_syscall_exit(regs, stepping); 384 } 385 386 387 /* 388 * regset functions. 389 */ 390 391 static int fpr_get(struct task_struct *target, 392 const struct user_regset *regset, 393 struct membuf to) 394 { 395 struct pt_regs *regs = task_regs(target); 396 397 return membuf_write(&to, regs->fr, ELF_NFPREG * sizeof(__u64)); 398 } 399 400 static int fpr_set(struct task_struct *target, 401 const struct user_regset *regset, 402 unsigned int pos, unsigned int count, 403 const void *kbuf, const void __user *ubuf) 404 { 405 struct pt_regs *regs = task_regs(target); 406 const __u64 *k = kbuf; 407 const __u64 __user *u = ubuf; 408 __u64 reg; 409 410 pos /= sizeof(reg); 411 count /= sizeof(reg); 412 413 if (kbuf) 414 for (; count > 0 && pos < ELF_NFPREG; --count) 415 regs->fr[pos++] = *k++; 416 else 417 for (; count > 0 && pos < ELF_NFPREG; --count) { 418 if (__get_user(reg, u++)) 419 return -EFAULT; 420 regs->fr[pos++] = reg; 421 } 422 423 kbuf = k; 424 ubuf = u; 425 pos *= sizeof(reg); 426 count *= sizeof(reg); 427 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 428 ELF_NFPREG * sizeof(reg), -1); 429 return 0; 430 } 431 432 #define RI(reg) (offsetof(struct user_regs_struct,reg) / sizeof(long)) 433 434 static unsigned long get_reg(struct pt_regs *regs, int num) 435 { 436 switch (num) { 437 case RI(gr[0]) ... RI(gr[31]): return regs->gr[num - RI(gr[0])]; 438 case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])]; 439 case RI(iasq[0]): return regs->iasq[0]; 440 case RI(iasq[1]): return regs->iasq[1]; 441 case RI(iaoq[0]): return regs->iaoq[0]; 442 case RI(iaoq[1]): return regs->iaoq[1]; 443 case RI(sar): return regs->sar; 444 case RI(iir): return regs->iir; 445 case RI(isr): return regs->isr; 446 case RI(ior): return regs->ior; 447 case RI(ipsw): return regs->ipsw; 448 case RI(cr27): return regs->cr27; 449 case RI(cr0): return mfctl(0); 450 case RI(cr24): return mfctl(24); 451 case RI(cr25): return mfctl(25); 452 case RI(cr26): return mfctl(26); 453 case RI(cr28): return mfctl(28); 454 case RI(cr29): return mfctl(29); 455 case RI(cr30): return mfctl(30); 456 case RI(cr31): return mfctl(31); 457 case RI(cr8): return mfctl(8); 458 case RI(cr9): return mfctl(9); 459 case RI(cr12): return mfctl(12); 460 case RI(cr13): return mfctl(13); 461 case RI(cr10): return mfctl(10); 462 case RI(cr15): return mfctl(15); 463 default: return 0; 464 } 465 } 466 467 static void set_reg(struct pt_regs *regs, int num, unsigned long val) 468 { 469 switch (num) { 470 case RI(gr[0]): /* 471 * PSW is in gr[0]. 472 * Allow writing to Nullify, Divide-step-correction, 473 * and carry/borrow bits. 474 * BEWARE, if you set N, and then single step, it won't 475 * stop on the nullified instruction. 476 */ 477 val &= USER_PSW_BITS; 478 regs->gr[0] &= ~USER_PSW_BITS; 479 regs->gr[0] |= val; 480 return; 481 case RI(gr[1]) ... RI(gr[31]): 482 regs->gr[num - RI(gr[0])] = val; 483 return; 484 case RI(iaoq[0]): 485 case RI(iaoq[1]): 486 /* set 2 lowest bits to ensure userspace privilege: */ 487 regs->iaoq[num - RI(iaoq[0])] = val | 3; 488 return; 489 case RI(sar): regs->sar = val; 490 return; 491 default: return; 492 #if 0 493 /* do not allow to change any of the following registers (yet) */ 494 case RI(sr[0]) ... RI(sr[7]): return regs->sr[num - RI(sr[0])]; 495 case RI(iasq[0]): return regs->iasq[0]; 496 case RI(iasq[1]): return regs->iasq[1]; 497 case RI(iir): return regs->iir; 498 case RI(isr): return regs->isr; 499 case RI(ior): return regs->ior; 500 case RI(ipsw): return regs->ipsw; 501 case RI(cr27): return regs->cr27; 502 case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31; 503 case cr8, cr9, cr12, cr13, cr10, cr15; 504 #endif 505 } 506 } 507 508 static int gpr_get(struct task_struct *target, 509 const struct user_regset *regset, 510 struct membuf to) 511 { 512 struct pt_regs *regs = task_regs(target); 513 unsigned int pos; 514 515 for (pos = 0; pos < ELF_NGREG; pos++) 516 membuf_store(&to, get_reg(regs, pos)); 517 return 0; 518 } 519 520 static int gpr_set(struct task_struct *target, 521 const struct user_regset *regset, 522 unsigned int pos, unsigned int count, 523 const void *kbuf, const void __user *ubuf) 524 { 525 struct pt_regs *regs = task_regs(target); 526 const unsigned long *k = kbuf; 527 const unsigned long __user *u = ubuf; 528 unsigned long reg; 529 530 pos /= sizeof(reg); 531 count /= sizeof(reg); 532 533 if (kbuf) 534 for (; count > 0 && pos < ELF_NGREG; --count) 535 set_reg(regs, pos++, *k++); 536 else 537 for (; count > 0 && pos < ELF_NGREG; --count) { 538 if (__get_user(reg, u++)) 539 return -EFAULT; 540 set_reg(regs, pos++, reg); 541 } 542 543 kbuf = k; 544 ubuf = u; 545 pos *= sizeof(reg); 546 count *= sizeof(reg); 547 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 548 ELF_NGREG * sizeof(reg), -1); 549 return 0; 550 } 551 552 static const struct user_regset native_regsets[] = { 553 [REGSET_GENERAL] = { 554 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG, 555 .size = sizeof(long), .align = sizeof(long), 556 .regset_get = gpr_get, .set = gpr_set 557 }, 558 [REGSET_FP] = { 559 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG, 560 .size = sizeof(__u64), .align = sizeof(__u64), 561 .regset_get = fpr_get, .set = fpr_set 562 } 563 }; 564 565 static const struct user_regset_view user_parisc_native_view = { 566 .name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX, 567 .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets) 568 }; 569 570 #ifdef CONFIG_64BIT 571 static int gpr32_get(struct task_struct *target, 572 const struct user_regset *regset, 573 struct membuf to) 574 { 575 struct pt_regs *regs = task_regs(target); 576 unsigned int pos; 577 578 for (pos = 0; pos < ELF_NGREG; pos++) 579 membuf_store(&to, (compat_ulong_t)get_reg(regs, pos)); 580 581 return 0; 582 } 583 584 static int gpr32_set(struct task_struct *target, 585 const struct user_regset *regset, 586 unsigned int pos, unsigned int count, 587 const void *kbuf, const void __user *ubuf) 588 { 589 struct pt_regs *regs = task_regs(target); 590 const compat_ulong_t *k = kbuf; 591 const compat_ulong_t __user *u = ubuf; 592 compat_ulong_t reg; 593 594 pos /= sizeof(reg); 595 count /= sizeof(reg); 596 597 if (kbuf) 598 for (; count > 0 && pos < ELF_NGREG; --count) 599 set_reg(regs, pos++, *k++); 600 else 601 for (; count > 0 && pos < ELF_NGREG; --count) { 602 if (__get_user(reg, u++)) 603 return -EFAULT; 604 set_reg(regs, pos++, reg); 605 } 606 607 kbuf = k; 608 ubuf = u; 609 pos *= sizeof(reg); 610 count *= sizeof(reg); 611 user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 612 ELF_NGREG * sizeof(reg), -1); 613 return 0; 614 } 615 616 /* 617 * These are the regset flavors matching the 32bit native set. 618 */ 619 static const struct user_regset compat_regsets[] = { 620 [REGSET_GENERAL] = { 621 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG, 622 .size = sizeof(compat_long_t), .align = sizeof(compat_long_t), 623 .regset_get = gpr32_get, .set = gpr32_set 624 }, 625 [REGSET_FP] = { 626 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG, 627 .size = sizeof(__u64), .align = sizeof(__u64), 628 .regset_get = fpr_get, .set = fpr_set 629 } 630 }; 631 632 static const struct user_regset_view user_parisc_compat_view = { 633 .name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX, 634 .regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets) 635 }; 636 #endif /* CONFIG_64BIT */ 637 638 const struct user_regset_view *task_user_regset_view(struct task_struct *task) 639 { 640 BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG); 641 BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG); 642 #ifdef CONFIG_64BIT 643 if (is_compat_task()) 644 return &user_parisc_compat_view; 645 #endif 646 return &user_parisc_native_view; 647 } 648 649 650 /* HAVE_REGS_AND_STACK_ACCESS_API feature */ 651 652 struct pt_regs_offset { 653 const char *name; 654 int offset; 655 }; 656 657 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)} 658 #define REG_OFFSET_INDEX(r,i) {.name = #r#i, .offset = offsetof(struct pt_regs, r[i])} 659 #define REG_OFFSET_END {.name = NULL, .offset = 0} 660 661 static const struct pt_regs_offset regoffset_table[] = { 662 REG_OFFSET_INDEX(gr,0), 663 REG_OFFSET_INDEX(gr,1), 664 REG_OFFSET_INDEX(gr,2), 665 REG_OFFSET_INDEX(gr,3), 666 REG_OFFSET_INDEX(gr,4), 667 REG_OFFSET_INDEX(gr,5), 668 REG_OFFSET_INDEX(gr,6), 669 REG_OFFSET_INDEX(gr,7), 670 REG_OFFSET_INDEX(gr,8), 671 REG_OFFSET_INDEX(gr,9), 672 REG_OFFSET_INDEX(gr,10), 673 REG_OFFSET_INDEX(gr,11), 674 REG_OFFSET_INDEX(gr,12), 675 REG_OFFSET_INDEX(gr,13), 676 REG_OFFSET_INDEX(gr,14), 677 REG_OFFSET_INDEX(gr,15), 678 REG_OFFSET_INDEX(gr,16), 679 REG_OFFSET_INDEX(gr,17), 680 REG_OFFSET_INDEX(gr,18), 681 REG_OFFSET_INDEX(gr,19), 682 REG_OFFSET_INDEX(gr,20), 683 REG_OFFSET_INDEX(gr,21), 684 REG_OFFSET_INDEX(gr,22), 685 REG_OFFSET_INDEX(gr,23), 686 REG_OFFSET_INDEX(gr,24), 687 REG_OFFSET_INDEX(gr,25), 688 REG_OFFSET_INDEX(gr,26), 689 REG_OFFSET_INDEX(gr,27), 690 REG_OFFSET_INDEX(gr,28), 691 REG_OFFSET_INDEX(gr,29), 692 REG_OFFSET_INDEX(gr,30), 693 REG_OFFSET_INDEX(gr,31), 694 REG_OFFSET_INDEX(sr,0), 695 REG_OFFSET_INDEX(sr,1), 696 REG_OFFSET_INDEX(sr,2), 697 REG_OFFSET_INDEX(sr,3), 698 REG_OFFSET_INDEX(sr,4), 699 REG_OFFSET_INDEX(sr,5), 700 REG_OFFSET_INDEX(sr,6), 701 REG_OFFSET_INDEX(sr,7), 702 REG_OFFSET_INDEX(iasq,0), 703 REG_OFFSET_INDEX(iasq,1), 704 REG_OFFSET_INDEX(iaoq,0), 705 REG_OFFSET_INDEX(iaoq,1), 706 REG_OFFSET_NAME(cr27), 707 REG_OFFSET_NAME(ksp), 708 REG_OFFSET_NAME(kpc), 709 REG_OFFSET_NAME(sar), 710 REG_OFFSET_NAME(iir), 711 REG_OFFSET_NAME(isr), 712 REG_OFFSET_NAME(ior), 713 REG_OFFSET_NAME(ipsw), 714 REG_OFFSET_END, 715 }; 716 717 /** 718 * regs_query_register_offset() - query register offset from its name 719 * @name: the name of a register 720 * 721 * regs_query_register_offset() returns the offset of a register in struct 722 * pt_regs from its name. If the name is invalid, this returns -EINVAL; 723 */ 724 int regs_query_register_offset(const char *name) 725 { 726 const struct pt_regs_offset *roff; 727 for (roff = regoffset_table; roff->name != NULL; roff++) 728 if (!strcmp(roff->name, name)) 729 return roff->offset; 730 return -EINVAL; 731 } 732 733 /** 734 * regs_query_register_name() - query register name from its offset 735 * @offset: the offset of a register in struct pt_regs. 736 * 737 * regs_query_register_name() returns the name of a register from its 738 * offset in struct pt_regs. If the @offset is invalid, this returns NULL; 739 */ 740 const char *regs_query_register_name(unsigned int offset) 741 { 742 const struct pt_regs_offset *roff; 743 for (roff = regoffset_table; roff->name != NULL; roff++) 744 if (roff->offset == offset) 745 return roff->name; 746 return NULL; 747 } 748 749 /** 750 * regs_within_kernel_stack() - check the address in the stack 751 * @regs: pt_regs which contains kernel stack pointer. 752 * @addr: address which is checked. 753 * 754 * regs_within_kernel_stack() checks @addr is within the kernel stack page(s). 755 * If @addr is within the kernel stack, it returns true. If not, returns false. 756 */ 757 int regs_within_kernel_stack(struct pt_regs *regs, unsigned long addr) 758 { 759 return ((addr & ~(THREAD_SIZE - 1)) == 760 (kernel_stack_pointer(regs) & ~(THREAD_SIZE - 1))); 761 } 762 763 /** 764 * regs_get_kernel_stack_nth() - get Nth entry of the stack 765 * @regs: pt_regs which contains kernel stack pointer. 766 * @n: stack entry number. 767 * 768 * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which 769 * is specified by @regs. If the @n th entry is NOT in the kernel stack, 770 * this returns 0. 771 */ 772 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n) 773 { 774 unsigned long *addr = (unsigned long *)kernel_stack_pointer(regs); 775 776 addr -= n; 777 778 if (!regs_within_kernel_stack(regs, (unsigned long)addr)) 779 return 0; 780 781 return *addr; 782 } 783