arch/parisc/kernel/ptrace.c

   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/tracehook.h>
  19 #include <linux/user.h>
  20 #include <linux/personality.h>
  21 #include <linux/regset.h>
  22 #include <linux/security.h>
  23 #include <linux/seccomp.h>
  24 #include <linux/compat.h>
  25 #include <linux/signal.h>
  26 #include <linux/audit.h>
  27
  28 #include <linux/uaccess.h>
  29 #include <asm/pgtable.h>
  30 #include <asm/processor.h>
  31 #include <asm/asm-offsets.h>
  32
  33 /* PSW bits we allow the debugger to modify */
  34 #define USER_PSW_BITS   (PSW_N | PSW_B | PSW_V | PSW_CB)
  35
  36 #define CREATE_TRACE_POINTS
  37 #include <trace/events/syscalls.h>
  38
  39 /*
  40  * These are our native regset flavors.
  41  */
  42 enum parisc_regset {
  43         REGSET_GENERAL,
  44         REGSET_FP
  45 };
  46
  47 /*
  48  * Called by kernel/ptrace.c when detaching..
  49  *
  50  * Make sure single step bits etc are not set.
  51  */
  52 void ptrace_disable(struct task_struct *task)
  53 {
  54         clear_tsk_thread_flag(task, TIF_SINGLESTEP);
  55         clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
  56
  57         /* make sure the trap bits are not set */
  58         pa_psw(task)->r = 0;
  59         pa_psw(task)->t = 0;
  60         pa_psw(task)->h = 0;
  61         pa_psw(task)->l = 0;
  62 }
  63
  64 /*
  65  * The following functions are called by ptrace_resume() when
  66  * enabling or disabling single/block tracing.
  67  */
  68 void user_disable_single_step(struct task_struct *task)
  69 {
  70         ptrace_disable(task);
  71 }
  72
  73 void user_enable_single_step(struct task_struct *task)
  74 {
  75         clear_tsk_thread_flag(task, TIF_BLOCKSTEP);
  76         set_tsk_thread_flag(task, TIF_SINGLESTEP);
  77
  78         if (pa_psw(task)->n) {
  79                 /* Nullified, just crank over the queue. */
  80                 task_regs(task)->iaoq[0] = task_regs(task)->iaoq[1];
  81                 task_regs(task)->iasq[0] = task_regs(task)->iasq[1];
  82                 task_regs(task)->iaoq[1] = task_regs(task)->iaoq[0] + 4;
  83                 pa_psw(task)->n = 0;
  84                 pa_psw(task)->x = 0;
  85                 pa_psw(task)->y = 0;
  86                 pa_psw(task)->z = 0;
  87                 pa_psw(task)->b = 0;
  88                 ptrace_disable(task);
  89                 /* Don't wake up the task, but let the
  90                    parent know something happened. */
  91                 force_sig_fault(SIGTRAP, TRAP_TRACE,
  92                                 (void __user *) (task_regs(task)->iaoq[0] & ~3),
  93                                 task);
  94                 /* notify_parent(task, SIGCHLD); */
  95                 return;
  96         }
  97
  98         /* Enable recovery counter traps.  The recovery counter
  99          * itself will be set to zero on a task switch.  If the
 100          * task is suspended on a syscall then the syscall return
 101          * path will overwrite the recovery counter with a suitable
 102          * value such that it traps once back in user space.  We
 103          * disable interrupts in the tasks PSW here also, to avoid
 104          * interrupts while the recovery counter is decrementing.
 105          */
 106         pa_psw(task)->r = 1;
 107         pa_psw(task)->t = 0;
 108         pa_psw(task)->h = 0;
 109         pa_psw(task)->l = 0;
 110 }
 111
 112 void user_enable_block_step(struct task_struct *task)
 113 {
 114         clear_tsk_thread_flag(task, TIF_SINGLESTEP);
 115         set_tsk_thread_flag(task, TIF_BLOCKSTEP);
 116
 117         /* Enable taken branch trap. */
 118         pa_psw(task)->r = 0;
 119         pa_psw(task)->t = 1;
 120         pa_psw(task)->h = 0;
 121         pa_psw(task)->l = 0;
 122 }
 123
 124 long arch_ptrace(struct task_struct *child, long request,
 125                  unsigned long addr, unsigned long data)
 126 {
 127         unsigned long __user *datap = (unsigned long __user *)data;
 128         unsigned long tmp;
 129         long ret = -EIO;
 130
 131         switch (request) {
 132
 133         /* Read the word at location addr in the USER area.  For ptraced
 134            processes, the kernel saves all regs on a syscall. */
 135         case PTRACE_PEEKUSR:
 136                 if ((addr & (sizeof(unsigned long)-1)) ||
 137                      addr >= sizeof(struct pt_regs))
 138                         break;
 139                 tmp = *(unsigned long *) ((char *) task_regs(child) + addr);
 140                 ret = put_user(tmp, datap);
 141                 break;
 142
 143         /* Write the word at location addr in the USER area.  This will need
 144            to change when the kernel no longer saves all regs on a syscall.
 145            FIXME.  There is a problem at the moment in that r3-r18 are only
 146            saved if the process is ptraced on syscall entry, and even then
 147            those values are overwritten by actual register values on syscall
 148            exit. */
 149         case PTRACE_POKEUSR:
 150                 /* Some register values written here may be ignored in
 151                  * entry.S:syscall_restore_rfi; e.g. iaoq is written with
 152                  * r31/r31+4, and not with the values in pt_regs.
 153                  */
 154                 if (addr == PT_PSW) {
 155                         /* Allow writing to Nullify, Divide-step-correction,
 156                          * and carry/borrow bits.
 157                          * BEWARE, if you set N, and then single step, it won't
 158                          * stop on the nullified instruction.
 159                          */
 160                         data &= USER_PSW_BITS;
 161                         task_regs(child)->gr[0] &= ~USER_PSW_BITS;
 162                         task_regs(child)->gr[0] |= data;
 163                         ret = 0;
 164                         break;
 165                 }
 166
 167                 if ((addr & (sizeof(unsigned long)-1)) ||
 168                      addr >= sizeof(struct pt_regs))
 169                         break;
 170                 if ((addr >= PT_GR1 && addr <= PT_GR31) ||
 171                                 addr == PT_IAOQ0 || addr == PT_IAOQ1 ||
 172                                 (addr >= PT_FR0 && addr <= PT_FR31 + 4) ||
 173                                 addr == PT_SAR) {
 174                         *(unsigned long *) ((char *) task_regs(child) + addr) = data;
 175                         ret = 0;
 176                 }
 177                 break;
 178
 179         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
 180                 return copy_regset_to_user(child,
 181                                            task_user_regset_view(current),
 182                                            REGSET_GENERAL,
 183                                            0, sizeof(struct user_regs_struct),
 184                                            datap);
 185
 186         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 187                 return copy_regset_from_user(child,
 188                                              task_user_regset_view(current),
 189                                              REGSET_GENERAL,
 190                                              0, sizeof(struct user_regs_struct),
 191                                              datap);
 192
 193         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
 194                 return copy_regset_to_user(child,
 195                                            task_user_regset_view(current),
 196                                            REGSET_FP,
 197                                            0, sizeof(struct user_fp_struct),
 198                                            datap);
 199
 200         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
 201                 return copy_regset_from_user(child,
 202                                              task_user_regset_view(current),
 203                                              REGSET_FP,
 204                                              0, sizeof(struct user_fp_struct),
 205                                              datap);
 206
 207         default:
 208                 ret = ptrace_request(child, request, addr, data);
 209                 break;
 210         }
 211
 212         return ret;
 213 }
 214
 215
 216 #ifdef CONFIG_COMPAT
 217
 218 /* This function is needed to translate 32 bit pt_regs offsets in to
 219  * 64 bit pt_regs offsets.  For example, a 32 bit gdb under a 64 bit kernel
 220  * will request offset 12 if it wants gr3, but the lower 32 bits of
 221  * the 64 bit kernels view of gr3 will be at offset 28 (3*8 + 4).
 222  * This code relies on a 32 bit pt_regs being comprised of 32 bit values
 223  * except for the fp registers which (a) are 64 bits, and (b) follow
 224  * the gr registers at the start of pt_regs.  The 32 bit pt_regs should
 225  * be half the size of the 64 bit pt_regs, plus 32*4 to allow for fr[]
 226  * being 64 bit in both cases.
 227  */
 228
 229 static compat_ulong_t translate_usr_offset(compat_ulong_t offset)
 230 {
 231         if (offset < 0)
 232                 return sizeof(struct pt_regs);
 233         else if (offset <= 32*4)        /* gr[0..31] */
 234                 return offset * 2 + 4;
 235         else if (offset <= 32*4+32*8)   /* gr[0..31] + fr[0..31] */
 236                 return offset + 32*4;
 237         else if (offset < sizeof(struct pt_regs)/2 + 32*4)
 238                 return offset * 2 + 4 - 32*8;
 239         else
 240                 return sizeof(struct pt_regs);
 241 }
 242
 243 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 244                         compat_ulong_t addr, compat_ulong_t data)
 245 {
 246         compat_uint_t tmp;
 247         long ret = -EIO;
 248
 249         switch (request) {
 250
 251         case PTRACE_PEEKUSR:
 252                 if (addr & (sizeof(compat_uint_t)-1))
 253                         break;
 254                 addr = translate_usr_offset(addr);
 255                 if (addr >= sizeof(struct pt_regs))
 256                         break;
 257
 258                 tmp = *(compat_uint_t *) ((char *) task_regs(child) + addr);
 259                 ret = put_user(tmp, (compat_uint_t *) (unsigned long) data);
 260                 break;
 261
 262         /* Write the word at location addr in the USER area.  This will need
 263            to change when the kernel no longer saves all regs on a syscall.
 264            FIXME.  There is a problem at the moment in that r3-r18 are only
 265            saved if the process is ptraced on syscall entry, and even then
 266            those values are overwritten by actual register values on syscall
 267            exit. */
 268         case PTRACE_POKEUSR:
 269                 /* Some register values written here may be ignored in
 270                  * entry.S:syscall_restore_rfi; e.g. iaoq is written with
 271                  * r31/r31+4, and not with the values in pt_regs.
 272                  */
 273                 if (addr == PT_PSW) {
 274                         /* Since PT_PSW==0, it is valid for 32 bit processes
 275                          * under 64 bit kernels as well.
 276                          */
 277                         ret = arch_ptrace(child, request, addr, data);
 278                 } else {
 279                         if (addr & (sizeof(compat_uint_t)-1))
 280                                 break;
 281                         addr = translate_usr_offset(addr);
 282                         if (addr >= sizeof(struct pt_regs))
 283                                 break;
 284                         if (addr >= PT_FR0 && addr <= PT_FR31 + 4) {
 285                                 /* Special case, fp regs are 64 bits anyway */
 286                                 *(__u64 *) ((char *) task_regs(child) + addr) = data;
 287                                 ret = 0;
 288                         }
 289                         else if ((addr >= PT_GR1+4 && addr <= PT_GR31+4) ||
 290                                         addr == PT_IAOQ0+4 || addr == PT_IAOQ1+4 ||
 291                                         addr == PT_SAR+4) {
 292                                 /* Zero the top 32 bits */
 293                                 *(__u32 *) ((char *) task_regs(child) + addr - 4) = 0;
 294                                 *(__u32 *) ((char *) task_regs(child) + addr) = data;
 295                                 ret = 0;
 296                         }
 297                 }
 298                 break;
 299
 300         default:
 301                 ret = compat_ptrace_request(child, request, addr, data);
 302                 break;
 303         }
 304
 305         return ret;
 306 }
 307 #endif
 308
 309 long do_syscall_trace_enter(struct pt_regs *regs)
 310 {
 311         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 312             tracehook_report_syscall_entry(regs)) {
 313                 /*
 314                  * Tracing decided this syscall should not happen or the
 315                  * debugger stored an invalid system call number. Skip
 316                  * the system call and the system call restart handling.
 317                  */
 318                 regs->gr[20] = -1UL;
 319                 goto out;
 320         }
 321
 322         /* Do the secure computing check after ptrace. */
 323         if (secure_computing(NULL) == -1)
 324                 return -1;
 325
 326 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 327         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 328                 trace_sys_enter(regs, regs->gr[20]);
 329 #endif
 330
 331 #ifdef CONFIG_64BIT
 332         if (!is_compat_task())
 333                 audit_syscall_entry(regs->gr[20], regs->gr[26], regs->gr[25],
 334                                     regs->gr[24], regs->gr[23]);
 335         else
 336 #endif
 337                 audit_syscall_entry(regs->gr[20] & 0xffffffff,
 338                         regs->gr[26] & 0xffffffff,
 339                         regs->gr[25] & 0xffffffff,
 340                         regs->gr[24] & 0xffffffff,
 341                         regs->gr[23] & 0xffffffff);
 342
 343 out:
 344         /*
 345          * Sign extend the syscall number to 64bit since it may have been
 346          * modified by a compat ptrace call
 347          */
 348         return (int) ((u32) regs->gr[20]);
 349 }
 350
 351 void do_syscall_trace_exit(struct pt_regs *regs)
 352 {
 353         int stepping = test_thread_flag(TIF_SINGLESTEP) ||
 354                 test_thread_flag(TIF_BLOCKSTEP);
 355
 356         audit_syscall_exit(regs);
 357
 358 #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS
 359         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 360                 trace_sys_exit(regs, regs->gr[20]);
 361 #endif
 362
 363         if (stepping || test_thread_flag(TIF_SYSCALL_TRACE))
 364                 tracehook_report_syscall_exit(regs, stepping);
 365 }
 366
 367
 368 /*
 369  * regset functions.
 370  */
 371
 372 static int fpr_get(struct task_struct *target,
 373                      const struct user_regset *regset,
 374                      unsigned int pos, unsigned int count,
 375                      void *kbuf, void __user *ubuf)
 376 {
 377         struct pt_regs *regs = task_regs(target);
 378         __u64 *k = kbuf;
 379         __u64 __user *u = ubuf;
 380         __u64 reg;
 381
 382         pos /= sizeof(reg);
 383         count /= sizeof(reg);
 384
 385         if (kbuf)
 386                 for (; count > 0 && pos < ELF_NFPREG; --count)
 387                         *k++ = regs->fr[pos++];
 388         else
 389                 for (; count > 0 && pos < ELF_NFPREG; --count)
 390                         if (__put_user(regs->fr[pos++], u++))
 391                                 return -EFAULT;
 392
 393         kbuf = k;
 394         ubuf = u;
 395         pos *= sizeof(reg);
 396         count *= sizeof(reg);
 397         return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 398                                         ELF_NFPREG * sizeof(reg), -1);
 399 }
 400
 401 static int fpr_set(struct task_struct *target,
 402                      const struct user_regset *regset,
 403                      unsigned int pos, unsigned int count,
 404                      const void *kbuf, const void __user *ubuf)
 405 {
 406         struct pt_regs *regs = task_regs(target);
 407         const __u64 *k = kbuf;
 408         const __u64 __user *u = ubuf;
 409         __u64 reg;
 410
 411         pos /= sizeof(reg);
 412         count /= sizeof(reg);
 413
 414         if (kbuf)
 415                 for (; count > 0 && pos < ELF_NFPREG; --count)
 416                         regs->fr[pos++] = *k++;
 417         else
 418                 for (; count > 0 && pos < ELF_NFPREG; --count) {
 419                         if (__get_user(reg, u++))
 420                                 return -EFAULT;
 421                         regs->fr[pos++] = reg;
 422                 }
 423
 424         kbuf = k;
 425         ubuf = u;
 426         pos *= sizeof(reg);
 427         count *= sizeof(reg);
 428         return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 429                                          ELF_NFPREG * sizeof(reg), -1);
 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                         regs->iaoq[num - RI(iaoq[0])] = val;
 487                         return;
 488         case RI(sar):   regs->sar = val;
 489                         return;
 490         default:        return;
 491 #if 0
 492         /* do not allow to change any of the following registers (yet) */
 493         case RI(sr[0]) ... RI(sr[7]):   return regs->sr[num - RI(sr[0])];
 494         case RI(iasq[0]):               return regs->iasq[0];
 495         case RI(iasq[1]):               return regs->iasq[1];
 496         case RI(iir):                   return regs->iir;
 497         case RI(isr):                   return regs->isr;
 498         case RI(ior):                   return regs->ior;
 499         case RI(ipsw):                  return regs->ipsw;
 500         case RI(cr27):                  return regs->cr27;
 501         case cr0, cr24, cr25, cr26, cr27, cr28, cr29, cr30, cr31;
 502         case cr8, cr9, cr12, cr13, cr10, cr15;
 503 #endif
 504         }
 505 }
 506
 507 static int gpr_get(struct task_struct *target,
 508                      const struct user_regset *regset,
 509                      unsigned int pos, unsigned int count,
 510                      void *kbuf, void __user *ubuf)
 511 {
 512         struct pt_regs *regs = task_regs(target);
 513         unsigned long *k = kbuf;
 514         unsigned long __user *u = ubuf;
 515         unsigned long reg;
 516
 517         pos /= sizeof(reg);
 518         count /= sizeof(reg);
 519
 520         if (kbuf)
 521                 for (; count > 0 && pos < ELF_NGREG; --count)
 522                         *k++ = get_reg(regs, pos++);
 523         else
 524                 for (; count > 0 && pos < ELF_NGREG; --count)
 525                         if (__put_user(get_reg(regs, pos++), u++))
 526                                 return -EFAULT;
 527         kbuf = k;
 528         ubuf = u;
 529         pos *= sizeof(reg);
 530         count *= sizeof(reg);
 531         return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 532                                         ELF_NGREG * sizeof(reg), -1);
 533 }
 534
 535 static int gpr_set(struct task_struct *target,
 536                      const struct user_regset *regset,
 537                      unsigned int pos, unsigned int count,
 538                      const void *kbuf, const void __user *ubuf)
 539 {
 540         struct pt_regs *regs = task_regs(target);
 541         const unsigned long *k = kbuf;
 542         const unsigned long __user *u = ubuf;
 543         unsigned long reg;
 544
 545         pos /= sizeof(reg);
 546         count /= sizeof(reg);
 547
 548         if (kbuf)
 549                 for (; count > 0 && pos < ELF_NGREG; --count)
 550                         set_reg(regs, pos++, *k++);
 551         else
 552                 for (; count > 0 && pos < ELF_NGREG; --count) {
 553                         if (__get_user(reg, u++))
 554                                 return -EFAULT;
 555                         set_reg(regs, pos++, reg);
 556                 }
 557
 558         kbuf = k;
 559         ubuf = u;
 560         pos *= sizeof(reg);
 561         count *= sizeof(reg);
 562         return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 563                                          ELF_NGREG * sizeof(reg), -1);
 564 }
 565
 566 static const struct user_regset native_regsets[] = {
 567         [REGSET_GENERAL] = {
 568                 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 569                 .size = sizeof(long), .align = sizeof(long),
 570                 .get = gpr_get, .set = gpr_set
 571         },
 572         [REGSET_FP] = {
 573                 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 574                 .size = sizeof(__u64), .align = sizeof(__u64),
 575                 .get = fpr_get, .set = fpr_set
 576         }
 577 };
 578
 579 static const struct user_regset_view user_parisc_native_view = {
 580         .name = "parisc", .e_machine = ELF_ARCH, .ei_osabi = ELFOSABI_LINUX,
 581         .regsets = native_regsets, .n = ARRAY_SIZE(native_regsets)
 582 };
 583
 584 #ifdef CONFIG_64BIT
 585 #include <linux/compat.h>
 586
 587 static int gpr32_get(struct task_struct *target,
 588                      const struct user_regset *regset,
 589                      unsigned int pos, unsigned int count,
 590                      void *kbuf, void __user *ubuf)
 591 {
 592         struct pt_regs *regs = task_regs(target);
 593         compat_ulong_t *k = kbuf;
 594         compat_ulong_t __user *u = ubuf;
 595         compat_ulong_t reg;
 596
 597         pos /= sizeof(reg);
 598         count /= sizeof(reg);
 599
 600         if (kbuf)
 601                 for (; count > 0 && pos < ELF_NGREG; --count)
 602                         *k++ = get_reg(regs, pos++);
 603         else
 604                 for (; count > 0 && pos < ELF_NGREG; --count)
 605                         if (__put_user((compat_ulong_t) get_reg(regs, pos++), u++))
 606                                 return -EFAULT;
 607
 608         kbuf = k;
 609         ubuf = u;
 610         pos *= sizeof(reg);
 611         count *= sizeof(reg);
 612         return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 613                                         ELF_NGREG * sizeof(reg), -1);
 614 }
 615
 616 static int gpr32_set(struct task_struct *target,
 617                      const struct user_regset *regset,
 618                      unsigned int pos, unsigned int count,
 619                      const void *kbuf, const void __user *ubuf)
 620 {
 621         struct pt_regs *regs = task_regs(target);
 622         const compat_ulong_t *k = kbuf;
 623         const compat_ulong_t __user *u = ubuf;
 624         compat_ulong_t reg;
 625
 626         pos /= sizeof(reg);
 627         count /= sizeof(reg);
 628
 629         if (kbuf)
 630                 for (; count > 0 && pos < ELF_NGREG; --count)
 631                         set_reg(regs, pos++, *k++);
 632         else
 633                 for (; count > 0 && pos < ELF_NGREG; --count) {
 634                         if (__get_user(reg, u++))
 635                                 return -EFAULT;
 636                         set_reg(regs, pos++, reg);
 637                 }
 638
 639         kbuf = k;
 640         ubuf = u;
 641         pos *= sizeof(reg);
 642         count *= sizeof(reg);
 643         return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 644                                          ELF_NGREG * sizeof(reg), -1);
 645 }
 646
 647 /*
 648  * These are the regset flavors matching the 32bit native set.
 649  */
 650 static const struct user_regset compat_regsets[] = {
 651         [REGSET_GENERAL] = {
 652                 .core_note_type = NT_PRSTATUS, .n = ELF_NGREG,
 653                 .size = sizeof(compat_long_t), .align = sizeof(compat_long_t),
 654                 .get = gpr32_get, .set = gpr32_set
 655         },
 656         [REGSET_FP] = {
 657                 .core_note_type = NT_PRFPREG, .n = ELF_NFPREG,
 658                 .size = sizeof(__u64), .align = sizeof(__u64),
 659                 .get = fpr_get, .set = fpr_set
 660         }
 661 };
 662
 663 static const struct user_regset_view user_parisc_compat_view = {
 664         .name = "parisc", .e_machine = EM_PARISC, .ei_osabi = ELFOSABI_LINUX,
 665         .regsets = compat_regsets, .n = ARRAY_SIZE(compat_regsets)
 666 };
 667 #endif  /* CONFIG_64BIT */
 668
 669 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 670 {
 671         BUILD_BUG_ON(sizeof(struct user_regs_struct)/sizeof(long) != ELF_NGREG);
 672         BUILD_BUG_ON(sizeof(struct user_fp_struct)/sizeof(__u64) != ELF_NFPREG);
 673 #ifdef CONFIG_64BIT
 674         if (is_compat_task())
 675                 return &user_parisc_compat_view;
 676 #endif
 677         return &user_parisc_native_view;
 678 }