arch/x86/kernel/ptrace.c

   1 /* By Ross Biro 1/23/92 */
   2 /*
   3  * Pentium III FXSR, SSE support
   4  *      Gareth Hughes <[email protected]>, May 2000
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/sched.h>
   9 #include <linux/sched/task_stack.h>
  10 #include <linux/mm.h>
  11 #include <linux/smp.h>
  12 #include <linux/errno.h>
  13 #include <linux/slab.h>
  14 #include <linux/ptrace.h>
  15 #include <linux/tracehook.h>
  16 #include <linux/user.h>
  17 #include <linux/elf.h>
  18 #include <linux/security.h>
  19 #include <linux/audit.h>
  20 #include <linux/seccomp.h>
  21 #include <linux/signal.h>
  22 #include <linux/perf_event.h>
  23 #include <linux/hw_breakpoint.h>
  24 #include <linux/rcupdate.h>
  25 #include <linux/export.h>
  26 #include <linux/context_tracking.h>
  27
  28 #include <linux/uaccess.h>
  29 #include <asm/pgtable.h>
  30 #include <asm/processor.h>
  31 #include <asm/fpu/internal.h>
  32 #include <asm/fpu/signal.h>
  33 #include <asm/fpu/regset.h>
  34 #include <asm/debugreg.h>
  35 #include <asm/ldt.h>
  36 #include <asm/desc.h>
  37 #include <asm/prctl.h>
  38 #include <asm/proto.h>
  39 #include <asm/hw_breakpoint.h>
  40 #include <asm/traps.h>
  41 #include <asm/syscall.h>
  42 #include <asm/fsgsbase.h>
  43
  44 #include "tls.h"
  45
  46 enum x86_regset {
  47         REGSET_GENERAL,
  48         REGSET_FP,
  49         REGSET_XFP,
  50         REGSET_IOPERM64 = REGSET_XFP,
  51         REGSET_XSTATE,
  52         REGSET_TLS,
  53         REGSET_IOPERM32,
  54 };
  55
  56 struct pt_regs_offset {
  57         const char *name;
  58         int offset;
  59 };
  60
  61 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
  62 #define REG_OFFSET_END {.name = NULL, .offset = 0}
  63
  64 static const struct pt_regs_offset regoffset_table[] = {
  65 #ifdef CONFIG_X86_64
  66         REG_OFFSET_NAME(r15),
  67         REG_OFFSET_NAME(r14),
  68         REG_OFFSET_NAME(r13),
  69         REG_OFFSET_NAME(r12),
  70         REG_OFFSET_NAME(r11),
  71         REG_OFFSET_NAME(r10),
  72         REG_OFFSET_NAME(r9),
  73         REG_OFFSET_NAME(r8),
  74 #endif
  75         REG_OFFSET_NAME(bx),
  76         REG_OFFSET_NAME(cx),
  77         REG_OFFSET_NAME(dx),
  78         REG_OFFSET_NAME(si),
  79         REG_OFFSET_NAME(di),
  80         REG_OFFSET_NAME(bp),
  81         REG_OFFSET_NAME(ax),
  82 #ifdef CONFIG_X86_32
  83         REG_OFFSET_NAME(ds),
  84         REG_OFFSET_NAME(es),
  85         REG_OFFSET_NAME(fs),
  86         REG_OFFSET_NAME(gs),
  87 #endif
  88         REG_OFFSET_NAME(orig_ax),
  89         REG_OFFSET_NAME(ip),
  90         REG_OFFSET_NAME(cs),
  91         REG_OFFSET_NAME(flags),
  92         REG_OFFSET_NAME(sp),
  93         REG_OFFSET_NAME(ss),
  94         REG_OFFSET_END,
  95 };
  96
  97 /**
  98  * regs_query_register_offset() - query register offset from its name
  99  * @name:       the name of a register
 100  *
 101  * regs_query_register_offset() returns the offset of a register in struct
 102  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 103  */
 104 int regs_query_register_offset(const char *name)
 105 {
 106         const struct pt_regs_offset *roff;
 107         for (roff = regoffset_table; roff->name != NULL; roff++)
 108                 if (!strcmp(roff->name, name))
 109                         return roff->offset;
 110         return -EINVAL;
 111 }
 112
 113 /**
 114  * regs_query_register_name() - query register name from its offset
 115  * @offset:     the offset of a register in struct pt_regs.
 116  *
 117  * regs_query_register_name() returns the name of a register from its
 118  * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
 119  */
 120 const char *regs_query_register_name(unsigned int offset)
 121 {
 122         const struct pt_regs_offset *roff;
 123         for (roff = regoffset_table; roff->name != NULL; roff++)
 124                 if (roff->offset == offset)
 125                         return roff->name;
 126         return NULL;
 127 }
 128
 129 /*
 130  * does not yet catch signals sent when the child dies.
 131  * in exit.c or in signal.c.
 132  */
 133
 134 /*
 135  * Determines which flags the user has access to [1 = access, 0 = no access].
 136  */
 137 #define FLAG_MASK_32            ((unsigned long)                        \
 138                                  (X86_EFLAGS_CF | X86_EFLAGS_PF |       \
 139                                   X86_EFLAGS_AF | X86_EFLAGS_ZF |       \
 140                                   X86_EFLAGS_SF | X86_EFLAGS_TF |       \
 141                                   X86_EFLAGS_DF | X86_EFLAGS_OF |       \
 142                                   X86_EFLAGS_RF | X86_EFLAGS_AC))
 143
 144 /*
 145  * Determines whether a value may be installed in a segment register.
 146  */
 147 static inline bool invalid_selector(u16 value)
 148 {
 149         return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
 150 }
 151
 152 #ifdef CONFIG_X86_32
 153
 154 #define FLAG_MASK               FLAG_MASK_32
 155
 156 /*
 157  * X86_32 CPUs don't save ss and esp if the CPU is already in kernel mode
 158  * when it traps.  The previous stack will be directly underneath the saved
 159  * registers, and 'sp/ss' won't even have been saved. Thus the '&regs->sp'.
 160  *
 161  * Now, if the stack is empty, '&regs->sp' is out of range. In this
 162  * case we try to take the previous stack. To always return a non-null
 163  * stack pointer we fall back to regs as stack if no previous stack
 164  * exists.
 165  *
 166  * This is valid only for kernel mode traps.
 167  */
 168 unsigned long kernel_stack_pointer(struct pt_regs *regs)
 169 {
 170         unsigned long context = (unsigned long)regs & ~(THREAD_SIZE - 1);
 171         unsigned long sp = (unsigned long)&regs->sp;
 172         u32 *prev_esp;
 173
 174         if (context == (sp & ~(THREAD_SIZE - 1)))
 175                 return sp;
 176
 177         prev_esp = (u32 *)(context);
 178         if (*prev_esp)
 179                 return (unsigned long)*prev_esp;
 180
 181         return (unsigned long)regs;
 182 }
 183 EXPORT_SYMBOL_GPL(kernel_stack_pointer);
 184
 185 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
 186 {
 187         BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
 188         return &regs->bx + (regno >> 2);
 189 }
 190
 191 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 192 {
 193         /*
 194          * Returning the value truncates it to 16 bits.
 195          */
 196         unsigned int retval;
 197         if (offset != offsetof(struct user_regs_struct, gs))
 198                 retval = *pt_regs_access(task_pt_regs(task), offset);
 199         else {
 200                 if (task == current)
 201                         retval = get_user_gs(task_pt_regs(task));
 202                 else
 203                         retval = task_user_gs(task);
 204         }
 205         return retval;
 206 }
 207
 208 static int set_segment_reg(struct task_struct *task,
 209                            unsigned long offset, u16 value)
 210 {
 211         /*
 212          * The value argument was already truncated to 16 bits.
 213          */
 214         if (invalid_selector(value))
 215                 return -EIO;
 216
 217         /*
 218          * For %cs and %ss we cannot permit a null selector.
 219          * We can permit a bogus selector as long as it has USER_RPL.
 220          * Null selectors are fine for other segment registers, but
 221          * we will never get back to user mode with invalid %cs or %ss
 222          * and will take the trap in iret instead.  Much code relies
 223          * on user_mode() to distinguish a user trap frame (which can
 224          * safely use invalid selectors) from a kernel trap frame.
 225          */
 226         switch (offset) {
 227         case offsetof(struct user_regs_struct, cs):
 228         case offsetof(struct user_regs_struct, ss):
 229                 if (unlikely(value == 0))
 230                         return -EIO;
 231
 232         default:
 233                 *pt_regs_access(task_pt_regs(task), offset) = value;
 234                 break;
 235
 236         case offsetof(struct user_regs_struct, gs):
 237                 if (task == current)
 238                         set_user_gs(task_pt_regs(task), value);
 239                 else
 240                         task_user_gs(task) = value;
 241         }
 242
 243         return 0;
 244 }
 245
 246 #else  /* CONFIG_X86_64 */
 247
 248 #define FLAG_MASK               (FLAG_MASK_32 | X86_EFLAGS_NT)
 249
 250 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
 251 {
 252         BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
 253         return &regs->r15 + (offset / sizeof(regs->r15));
 254 }
 255
 256 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 257 {
 258         /*
 259          * Returning the value truncates it to 16 bits.
 260          */
 261         unsigned int seg;
 262
 263         switch (offset) {
 264         case offsetof(struct user_regs_struct, fs):
 265                 if (task == current) {
 266                         /* Older gas can't assemble movq %?s,%r?? */
 267                         asm("movl %%fs,%0" : "=r" (seg));
 268                         return seg;
 269                 }
 270                 return task->thread.fsindex;
 271         case offsetof(struct user_regs_struct, gs):
 272                 if (task == current) {
 273                         asm("movl %%gs,%0" : "=r" (seg));
 274                         return seg;
 275                 }
 276                 return task->thread.gsindex;
 277         case offsetof(struct user_regs_struct, ds):
 278                 if (task == current) {
 279                         asm("movl %%ds,%0" : "=r" (seg));
 280                         return seg;
 281                 }
 282                 return task->thread.ds;
 283         case offsetof(struct user_regs_struct, es):
 284                 if (task == current) {
 285                         asm("movl %%es,%0" : "=r" (seg));
 286                         return seg;
 287                 }
 288                 return task->thread.es;
 289
 290         case offsetof(struct user_regs_struct, cs):
 291         case offsetof(struct user_regs_struct, ss):
 292                 break;
 293         }
 294         return *pt_regs_access(task_pt_regs(task), offset);
 295 }
 296
 297 static int set_segment_reg(struct task_struct *task,
 298                            unsigned long offset, u16 value)
 299 {
 300         /*
 301          * The value argument was already truncated to 16 bits.
 302          */
 303         if (invalid_selector(value))
 304                 return -EIO;
 305
 306         switch (offset) {
 307         case offsetof(struct user_regs_struct,fs):
 308                 task->thread.fsindex = value;
 309                 if (task == current)
 310                         loadsegment(fs, task->thread.fsindex);
 311                 break;
 312         case offsetof(struct user_regs_struct,gs):
 313                 task->thread.gsindex = value;
 314                 if (task == current)
 315                         load_gs_index(task->thread.gsindex);
 316                 break;
 317         case offsetof(struct user_regs_struct,ds):
 318                 task->thread.ds = value;
 319                 if (task == current)
 320                         loadsegment(ds, task->thread.ds);
 321                 break;
 322         case offsetof(struct user_regs_struct,es):
 323                 task->thread.es = value;
 324                 if (task == current)
 325                         loadsegment(es, task->thread.es);
 326                 break;
 327
 328                 /*
 329                  * Can't actually change these in 64-bit mode.
 330                  */
 331         case offsetof(struct user_regs_struct,cs):
 332                 if (unlikely(value == 0))
 333                         return -EIO;
 334                 task_pt_regs(task)->cs = value;
 335                 break;
 336         case offsetof(struct user_regs_struct,ss):
 337                 if (unlikely(value == 0))
 338                         return -EIO;
 339                 task_pt_regs(task)->ss = value;
 340                 break;
 341         }
 342
 343         return 0;
 344 }
 345
 346 #endif  /* CONFIG_X86_32 */
 347
 348 static unsigned long get_flags(struct task_struct *task)
 349 {
 350         unsigned long retval = task_pt_regs(task)->flags;
 351
 352         /*
 353          * If the debugger set TF, hide it from the readout.
 354          */
 355         if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 356                 retval &= ~X86_EFLAGS_TF;
 357
 358         return retval;
 359 }
 360
 361 static int set_flags(struct task_struct *task, unsigned long value)
 362 {
 363         struct pt_regs *regs = task_pt_regs(task);
 364
 365         /*
 366          * If the user value contains TF, mark that
 367          * it was not "us" (the debugger) that set it.
 368          * If not, make sure it stays set if we had.
 369          */
 370         if (value & X86_EFLAGS_TF)
 371                 clear_tsk_thread_flag(task, TIF_FORCED_TF);
 372         else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 373                 value |= X86_EFLAGS_TF;
 374
 375         regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
 376
 377         return 0;
 378 }
 379
 380 static int putreg(struct task_struct *child,
 381                   unsigned long offset, unsigned long value)
 382 {
 383         switch (offset) {
 384         case offsetof(struct user_regs_struct, cs):
 385         case offsetof(struct user_regs_struct, ds):
 386         case offsetof(struct user_regs_struct, es):
 387         case offsetof(struct user_regs_struct, fs):
 388         case offsetof(struct user_regs_struct, gs):
 389         case offsetof(struct user_regs_struct, ss):
 390                 return set_segment_reg(child, offset, value);
 391
 392         case offsetof(struct user_regs_struct, flags):
 393                 return set_flags(child, value);
 394
 395 #ifdef CONFIG_X86_64
 396         case offsetof(struct user_regs_struct,fs_base):
 397                 if (value >= TASK_SIZE_MAX)
 398                         return -EIO;
 399                 /*
 400                  * When changing the FS base, use the same
 401                  * mechanism as for do_arch_prctl_64().
 402                  */
 403                 if (child->thread.fsbase != value)
 404                         return x86_fsbase_write_task(child, value);
 405                 return 0;
 406         case offsetof(struct user_regs_struct,gs_base):
 407                 /*
 408                  * Exactly the same here as the %fs handling above.
 409                  */
 410                 if (value >= TASK_SIZE_MAX)
 411                         return -EIO;
 412                 if (child->thread.gsbase != value)
 413                         return x86_gsbase_write_task(child, value);
 414                 return 0;
 415 #endif
 416         }
 417
 418         *pt_regs_access(task_pt_regs(child), offset) = value;
 419         return 0;
 420 }
 421
 422 static unsigned long getreg(struct task_struct *task, unsigned long offset)
 423 {
 424         switch (offset) {
 425         case offsetof(struct user_regs_struct, cs):
 426         case offsetof(struct user_regs_struct, ds):
 427         case offsetof(struct user_regs_struct, es):
 428         case offsetof(struct user_regs_struct, fs):
 429         case offsetof(struct user_regs_struct, gs):
 430         case offsetof(struct user_regs_struct, ss):
 431                 return get_segment_reg(task, offset);
 432
 433         case offsetof(struct user_regs_struct, flags):
 434                 return get_flags(task);
 435
 436 #ifdef CONFIG_X86_64
 437         case offsetof(struct user_regs_struct, fs_base):
 438                 return x86_fsbase_read_task(task);
 439         case offsetof(struct user_regs_struct, gs_base):
 440                 return x86_gsbase_read_task(task);
 441 #endif
 442         }
 443
 444         return *pt_regs_access(task_pt_regs(task), offset);
 445 }
 446
 447 static int genregs_get(struct task_struct *target,
 448                        const struct user_regset *regset,
 449                        unsigned int pos, unsigned int count,
 450                        void *kbuf, void __user *ubuf)
 451 {
 452         if (kbuf) {
 453                 unsigned long *k = kbuf;
 454                 while (count >= sizeof(*k)) {
 455                         *k++ = getreg(target, pos);
 456                         count -= sizeof(*k);
 457                         pos += sizeof(*k);
 458                 }
 459         } else {
 460                 unsigned long __user *u = ubuf;
 461                 while (count >= sizeof(*u)) {
 462                         if (__put_user(getreg(target, pos), u++))
 463                                 return -EFAULT;
 464                         count -= sizeof(*u);
 465                         pos += sizeof(*u);
 466                 }
 467         }
 468
 469         return 0;
 470 }
 471
 472 static int genregs_set(struct task_struct *target,
 473                        const struct user_regset *regset,
 474                        unsigned int pos, unsigned int count,
 475                        const void *kbuf, const void __user *ubuf)
 476 {
 477         int ret = 0;
 478         if (kbuf) {
 479                 const unsigned long *k = kbuf;
 480                 while (count >= sizeof(*k) && !ret) {
 481                         ret = putreg(target, pos, *k++);
 482                         count -= sizeof(*k);
 483                         pos += sizeof(*k);
 484                 }
 485         } else {
 486                 const unsigned long  __user *u = ubuf;
 487                 while (count >= sizeof(*u) && !ret) {
 488                         unsigned long word;
 489                         ret = __get_user(word, u++);
 490                         if (ret)
 491                                 break;
 492                         ret = putreg(target, pos, word);
 493                         count -= sizeof(*u);
 494                         pos += sizeof(*u);
 495                 }
 496         }
 497         return ret;
 498 }
 499
 500 static void ptrace_triggered(struct perf_event *bp,
 501                              struct perf_sample_data *data,
 502                              struct pt_regs *regs)
 503 {
 504         int i;
 505         struct thread_struct *thread = &(current->thread);
 506
 507         /*
 508          * Store in the virtual DR6 register the fact that the breakpoint
 509          * was hit so the thread's debugger will see it.
 510          */
 511         for (i = 0; i < HBP_NUM; i++) {
 512                 if (thread->ptrace_bps[i] == bp)
 513                         break;
 514         }
 515
 516         thread->debugreg6 |= (DR_TRAP0 << i);
 517 }
 518
 519 /*
 520  * Walk through every ptrace breakpoints for this thread and
 521  * build the dr7 value on top of their attributes.
 522  *
 523  */
 524 static unsigned long ptrace_get_dr7(struct perf_event *bp[])
 525 {
 526         int i;
 527         int dr7 = 0;
 528         struct arch_hw_breakpoint *info;
 529
 530         for (i = 0; i < HBP_NUM; i++) {
 531                 if (bp[i] && !bp[i]->attr.disabled) {
 532                         info = counter_arch_bp(bp[i]);
 533                         dr7 |= encode_dr7(i, info->len, info->type);
 534                 }
 535         }
 536
 537         return dr7;
 538 }
 539
 540 static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
 541                                         int len, int type, bool disabled)
 542 {
 543         int err, bp_len, bp_type;
 544
 545         err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
 546         if (!err) {
 547                 attr->bp_len = bp_len;
 548                 attr->bp_type = bp_type;
 549                 attr->disabled = disabled;
 550         }
 551
 552         return err;
 553 }
 554
 555 static struct perf_event *
 556 ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
 557                                 unsigned long addr, bool disabled)
 558 {
 559         struct perf_event_attr attr;
 560         int err;
 561
 562         ptrace_breakpoint_init(&attr);
 563         attr.bp_addr = addr;
 564
 565         err = ptrace_fill_bp_fields(&attr, len, type, disabled);
 566         if (err)
 567                 return ERR_PTR(err);
 568
 569         return register_user_hw_breakpoint(&attr, ptrace_triggered,
 570                                                  NULL, tsk);
 571 }
 572
 573 static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
 574                                         int disabled)
 575 {
 576         struct perf_event_attr attr = bp->attr;
 577         int err;
 578
 579         err = ptrace_fill_bp_fields(&attr, len, type, disabled);
 580         if (err)
 581                 return err;
 582
 583         return modify_user_hw_breakpoint(bp, &attr);
 584 }
 585
 586 /*
 587  * Handle ptrace writes to debug register 7.
 588  */
 589 static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
 590 {
 591         struct thread_struct *thread = &tsk->thread;
 592         unsigned long old_dr7;
 593         bool second_pass = false;
 594         int i, rc, ret = 0;
 595
 596         data &= ~DR_CONTROL_RESERVED;
 597         old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
 598
 599 restore:
 600         rc = 0;
 601         for (i = 0; i < HBP_NUM; i++) {
 602                 unsigned len, type;
 603                 bool disabled = !decode_dr7(data, i, &len, &type);
 604                 struct perf_event *bp = thread->ptrace_bps[i];
 605
 606                 if (!bp) {
 607                         if (disabled)
 608                                 continue;
 609
 610                         bp = ptrace_register_breakpoint(tsk,
 611                                         len, type, 0, disabled);
 612                         if (IS_ERR(bp)) {
 613                                 rc = PTR_ERR(bp);
 614                                 break;
 615                         }
 616
 617                         thread->ptrace_bps[i] = bp;
 618                         continue;
 619                 }
 620
 621                 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
 622                 if (rc)
 623                         break;
 624         }
 625
 626         /* Restore if the first pass failed, second_pass shouldn't fail. */
 627         if (rc && !WARN_ON(second_pass)) {
 628                 ret = rc;
 629                 data = old_dr7;
 630                 second_pass = true;
 631                 goto restore;
 632         }
 633
 634         return ret;
 635 }
 636
 637 /*
 638  * Handle PTRACE_PEEKUSR calls for the debug register area.
 639  */
 640 static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
 641 {
 642         struct thread_struct *thread = &tsk->thread;
 643         unsigned long val = 0;
 644
 645         if (n < HBP_NUM) {
 646                 struct perf_event *bp = thread->ptrace_bps[n];
 647
 648                 if (bp)
 649                         val = bp->hw.info.address;
 650         } else if (n == 6) {
 651                 val = thread->debugreg6;
 652         } else if (n == 7) {
 653                 val = thread->ptrace_dr7;
 654         }
 655         return val;
 656 }
 657
 658 static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
 659                                       unsigned long addr)
 660 {
 661         struct thread_struct *t = &tsk->thread;
 662         struct perf_event *bp = t->ptrace_bps[nr];
 663         int err = 0;
 664
 665         if (!bp) {
 666                 /*
 667                  * Put stub len and type to create an inactive but correct bp.
 668                  *
 669                  * CHECKME: the previous code returned -EIO if the addr wasn't
 670                  * a valid task virtual addr. The new one will return -EINVAL in
 671                  *  this case.
 672                  * -EINVAL may be what we want for in-kernel breakpoints users,
 673                  * but -EIO looks better for ptrace, since we refuse a register
 674                  * writing for the user. And anyway this is the previous
 675                  * behaviour.
 676                  */
 677                 bp = ptrace_register_breakpoint(tsk,
 678                                 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
 679                                 addr, true);
 680                 if (IS_ERR(bp))
 681                         err = PTR_ERR(bp);
 682                 else
 683                         t->ptrace_bps[nr] = bp;
 684         } else {
 685                 struct perf_event_attr attr = bp->attr;
 686
 687                 attr.bp_addr = addr;
 688                 err = modify_user_hw_breakpoint(bp, &attr);
 689         }
 690
 691         return err;
 692 }
 693
 694 /*
 695  * Handle PTRACE_POKEUSR calls for the debug register area.
 696  */
 697 static int ptrace_set_debugreg(struct task_struct *tsk, int n,
 698                                unsigned long val)
 699 {
 700         struct thread_struct *thread = &tsk->thread;
 701         /* There are no DR4 or DR5 registers */
 702         int rc = -EIO;
 703
 704         if (n < HBP_NUM) {
 705                 rc = ptrace_set_breakpoint_addr(tsk, n, val);
 706         } else if (n == 6) {
 707                 thread->debugreg6 = val;
 708                 rc = 0;
 709         } else if (n == 7) {
 710                 rc = ptrace_write_dr7(tsk, val);
 711                 if (!rc)
 712                         thread->ptrace_dr7 = val;
 713         }
 714         return rc;
 715 }
 716
 717 /*
 718  * These access the current or another (stopped) task's io permission
 719  * bitmap for debugging or core dump.
 720  */
 721 static int ioperm_active(struct task_struct *target,
 722                          const struct user_regset *regset)
 723 {
 724         return target->thread.io_bitmap_max / regset->size;
 725 }
 726
 727 static int ioperm_get(struct task_struct *target,
 728                       const struct user_regset *regset,
 729                       unsigned int pos, unsigned int count,
 730                       void *kbuf, void __user *ubuf)
 731 {
 732         if (!target->thread.io_bitmap_ptr)
 733                 return -ENXIO;
 734
 735         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 736                                    target->thread.io_bitmap_ptr,
 737                                    0, IO_BITMAP_BYTES);
 738 }
 739
 740 /*
 741  * Called by kernel/ptrace.c when detaching..
 742  *
 743  * Make sure the single step bit is not set.
 744  */
 745 void ptrace_disable(struct task_struct *child)
 746 {
 747         user_disable_single_step(child);
 748 #ifdef TIF_SYSCALL_EMU
 749         clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 750 #endif
 751 }
 752
 753 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 754 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
 755 #endif
 756
 757 long arch_ptrace(struct task_struct *child, long request,
 758                  unsigned long addr, unsigned long data)
 759 {
 760         int ret;
 761         unsigned long __user *datap = (unsigned long __user *)data;
 762
 763         switch (request) {
 764         /* read the word at location addr in the USER area. */
 765         case PTRACE_PEEKUSR: {
 766                 unsigned long tmp;
 767
 768                 ret = -EIO;
 769                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 770                         break;
 771
 772                 tmp = 0;  /* Default return condition */
 773                 if (addr < sizeof(struct user_regs_struct))
 774                         tmp = getreg(child, addr);
 775                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 776                          addr <= offsetof(struct user, u_debugreg[7])) {
 777                         addr -= offsetof(struct user, u_debugreg[0]);
 778                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
 779                 }
 780                 ret = put_user(tmp, datap);
 781                 break;
 782         }
 783
 784         case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 785                 ret = -EIO;
 786                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 787                         break;
 788
 789                 if (addr < sizeof(struct user_regs_struct))
 790                         ret = putreg(child, addr, data);
 791                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 792                          addr <= offsetof(struct user, u_debugreg[7])) {
 793                         addr -= offsetof(struct user, u_debugreg[0]);
 794                         ret = ptrace_set_debugreg(child,
 795                                                   addr / sizeof(data), data);
 796                 }
 797                 break;
 798
 799         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
 800                 return copy_regset_to_user(child,
 801                                            task_user_regset_view(current),
 802                                            REGSET_GENERAL,
 803                                            0, sizeof(struct user_regs_struct),
 804                                            datap);
 805
 806         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 807                 return copy_regset_from_user(child,
 808                                              task_user_regset_view(current),
 809                                              REGSET_GENERAL,
 810                                              0, sizeof(struct user_regs_struct),
 811                                              datap);
 812
 813         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
 814                 return copy_regset_to_user(child,
 815                                            task_user_regset_view(current),
 816                                            REGSET_FP,
 817                                            0, sizeof(struct user_i387_struct),
 818                                            datap);
 819
 820         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
 821                 return copy_regset_from_user(child,
 822                                              task_user_regset_view(current),
 823                                              REGSET_FP,
 824                                              0, sizeof(struct user_i387_struct),
 825                                              datap);
 826
 827 #ifdef CONFIG_X86_32
 828         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
 829                 return copy_regset_to_user(child, &user_x86_32_view,
 830                                            REGSET_XFP,
 831                                            0, sizeof(struct user_fxsr_struct),
 832                                            datap) ? -EIO : 0;
 833
 834         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
 835                 return copy_regset_from_user(child, &user_x86_32_view,
 836                                              REGSET_XFP,
 837                                              0, sizeof(struct user_fxsr_struct),
 838                                              datap) ? -EIO : 0;
 839 #endif
 840
 841 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 842         case PTRACE_GET_THREAD_AREA:
 843                 if ((int) addr < 0)
 844                         return -EIO;
 845                 ret = do_get_thread_area(child, addr,
 846                                         (struct user_desc __user *)data);
 847                 break;
 848
 849         case PTRACE_SET_THREAD_AREA:
 850                 if ((int) addr < 0)
 851                         return -EIO;
 852                 ret = do_set_thread_area(child, addr,
 853                                         (struct user_desc __user *)data, 0);
 854                 break;
 855 #endif
 856
 857 #ifdef CONFIG_X86_64
 858                 /* normal 64bit interface to access TLS data.
 859                    Works just like arch_prctl, except that the arguments
 860                    are reversed. */
 861         case PTRACE_ARCH_PRCTL:
 862                 ret = do_arch_prctl_64(child, data, addr);
 863                 break;
 864 #endif
 865
 866         default:
 867                 ret = ptrace_request(child, request, addr, data);
 868                 break;
 869         }
 870
 871         return ret;
 872 }
 873
 874 #ifdef CONFIG_IA32_EMULATION
 875
 876 #include <linux/compat.h>
 877 #include <linux/syscalls.h>
 878 #include <asm/ia32.h>
 879 #include <asm/user32.h>
 880
 881 #define R32(l,q)                                                        \
 882         case offsetof(struct user32, regs.l):                           \
 883                 regs->q = value; break
 884
 885 #define SEG32(rs)                                                       \
 886         case offsetof(struct user32, regs.rs):                          \
 887                 return set_segment_reg(child,                           \
 888                                        offsetof(struct user_regs_struct, rs), \
 889                                        value);                          \
 890                 break
 891
 892 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
 893 {
 894         struct pt_regs *regs = task_pt_regs(child);
 895
 896         switch (regno) {
 897
 898         SEG32(cs);
 899         SEG32(ds);
 900         SEG32(es);
 901         SEG32(fs);
 902         SEG32(gs);
 903         SEG32(ss);
 904
 905         R32(ebx, bx);
 906         R32(ecx, cx);
 907         R32(edx, dx);
 908         R32(edi, di);
 909         R32(esi, si);
 910         R32(ebp, bp);
 911         R32(eax, ax);
 912         R32(eip, ip);
 913         R32(esp, sp);
 914
 915         case offsetof(struct user32, regs.orig_eax):
 916                 /*
 917                  * Warning: bizarre corner case fixup here.  A 32-bit
 918                  * debugger setting orig_eax to -1 wants to disable
 919                  * syscall restart.  Make sure that the syscall
 920                  * restart code sign-extends orig_ax.  Also make sure
 921                  * we interpret the -ERESTART* codes correctly if
 922                  * loaded into regs->ax in case the task is not
 923                  * actually still sitting at the exit from a 32-bit
 924                  * syscall with TS_COMPAT still set.
 925                  */
 926                 regs->orig_ax = value;
 927                 if (syscall_get_nr(child, regs) >= 0)
 928                         child->thread_info.status |= TS_I386_REGS_POKED;
 929                 break;
 930
 931         case offsetof(struct user32, regs.eflags):
 932                 return set_flags(child, value);
 933
 934         case offsetof(struct user32, u_debugreg[0]) ...
 935                 offsetof(struct user32, u_debugreg[7]):
 936                 regno -= offsetof(struct user32, u_debugreg[0]);
 937                 return ptrace_set_debugreg(child, regno / 4, value);
 938
 939         default:
 940                 if (regno > sizeof(struct user32) || (regno & 3))
 941                         return -EIO;
 942
 943                 /*
 944                  * Other dummy fields in the virtual user structure
 945                  * are ignored
 946                  */
 947                 break;
 948         }
 949         return 0;
 950 }
 951
 952 #undef R32
 953 #undef SEG32
 954
 955 #define R32(l,q)                                                        \
 956         case offsetof(struct user32, regs.l):                           \
 957                 *val = regs->q; break
 958
 959 #define SEG32(rs)                                                       \
 960         case offsetof(struct user32, regs.rs):                          \
 961                 *val = get_segment_reg(child,                           \
 962                                        offsetof(struct user_regs_struct, rs)); \
 963                 break
 964
 965 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
 966 {
 967         struct pt_regs *regs = task_pt_regs(child);
 968
 969         switch (regno) {
 970
 971         SEG32(ds);
 972         SEG32(es);
 973         SEG32(fs);
 974         SEG32(gs);
 975
 976         R32(cs, cs);
 977         R32(ss, ss);
 978         R32(ebx, bx);
 979         R32(ecx, cx);
 980         R32(edx, dx);
 981         R32(edi, di);
 982         R32(esi, si);
 983         R32(ebp, bp);
 984         R32(eax, ax);
 985         R32(orig_eax, orig_ax);
 986         R32(eip, ip);
 987         R32(esp, sp);
 988
 989         case offsetof(struct user32, regs.eflags):
 990                 *val = get_flags(child);
 991                 break;
 992
 993         case offsetof(struct user32, u_debugreg[0]) ...
 994                 offsetof(struct user32, u_debugreg[7]):
 995                 regno -= offsetof(struct user32, u_debugreg[0]);
 996                 *val = ptrace_get_debugreg(child, regno / 4);
 997                 break;
 998
 999         default:
1000                 if (regno > sizeof(struct user32) || (regno & 3))
1001                         return -EIO;
1002
1003                 /*
1004                  * Other dummy fields in the virtual user structure
1005                  * are ignored
1006                  */
1007                 *val = 0;
1008                 break;
1009         }
1010         return 0;
1011 }
1012
1013 #undef R32
1014 #undef SEG32
1015
1016 static int genregs32_get(struct task_struct *target,
1017                          const struct user_regset *regset,
1018                          unsigned int pos, unsigned int count,
1019                          void *kbuf, void __user *ubuf)
1020 {
1021         if (kbuf) {
1022                 compat_ulong_t *k = kbuf;
1023                 while (count >= sizeof(*k)) {
1024                         getreg32(target, pos, k++);
1025                         count -= sizeof(*k);
1026                         pos += sizeof(*k);
1027                 }
1028         } else {
1029                 compat_ulong_t __user *u = ubuf;
1030                 while (count >= sizeof(*u)) {
1031                         compat_ulong_t word;
1032                         getreg32(target, pos, &word);
1033                         if (__put_user(word, u++))
1034                                 return -EFAULT;
1035                         count -= sizeof(*u);
1036                         pos += sizeof(*u);
1037                 }
1038         }
1039
1040         return 0;
1041 }
1042
1043 static int genregs32_set(struct task_struct *target,
1044                          const struct user_regset *regset,
1045                          unsigned int pos, unsigned int count,
1046                          const void *kbuf, const void __user *ubuf)
1047 {
1048         int ret = 0;
1049         if (kbuf) {
1050                 const compat_ulong_t *k = kbuf;
1051                 while (count >= sizeof(*k) && !ret) {
1052                         ret = putreg32(target, pos, *k++);
1053                         count -= sizeof(*k);
1054                         pos += sizeof(*k);
1055                 }
1056         } else {
1057                 const compat_ulong_t __user *u = ubuf;
1058                 while (count >= sizeof(*u) && !ret) {
1059                         compat_ulong_t word;
1060                         ret = __get_user(word, u++);
1061                         if (ret)
1062                                 break;
1063                         ret = putreg32(target, pos, word);
1064                         count -= sizeof(*u);
1065                         pos += sizeof(*u);
1066                 }
1067         }
1068         return ret;
1069 }
1070
1071 static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1072                              compat_ulong_t caddr, compat_ulong_t cdata)
1073 {
1074         unsigned long addr = caddr;
1075         unsigned long data = cdata;
1076         void __user *datap = compat_ptr(data);
1077         int ret;
1078         __u32 val;
1079
1080         switch (request) {
1081         case PTRACE_PEEKUSR:
1082                 ret = getreg32(child, addr, &val);
1083                 if (ret == 0)
1084                         ret = put_user(val, (__u32 __user *)datap);
1085                 break;
1086
1087         case PTRACE_POKEUSR:
1088                 ret = putreg32(child, addr, data);
1089                 break;
1090
1091         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1092                 return copy_regset_to_user(child, &user_x86_32_view,
1093                                            REGSET_GENERAL,
1094                                            0, sizeof(struct user_regs_struct32),
1095                                            datap);
1096
1097         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1098                 return copy_regset_from_user(child, &user_x86_32_view,
1099                                              REGSET_GENERAL, 0,
1100                                              sizeof(struct user_regs_struct32),
1101                                              datap);
1102
1103         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1104                 return copy_regset_to_user(child, &user_x86_32_view,
1105                                            REGSET_FP, 0,
1106                                            sizeof(struct user_i387_ia32_struct),
1107                                            datap);
1108
1109         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1110                 return copy_regset_from_user(
1111                         child, &user_x86_32_view, REGSET_FP,
1112                         0, sizeof(struct user_i387_ia32_struct), datap);
1113
1114         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1115                 return copy_regset_to_user(child, &user_x86_32_view,
1116                                            REGSET_XFP, 0,
1117                                            sizeof(struct user32_fxsr_struct),
1118                                            datap);
1119
1120         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1121                 return copy_regset_from_user(child, &user_x86_32_view,
1122                                              REGSET_XFP, 0,
1123                                              sizeof(struct user32_fxsr_struct),
1124                                              datap);
1125
1126         case PTRACE_GET_THREAD_AREA:
1127         case PTRACE_SET_THREAD_AREA:
1128                 return arch_ptrace(child, request, addr, data);
1129
1130         default:
1131                 return compat_ptrace_request(child, request, addr, data);
1132         }
1133
1134         return ret;
1135 }
1136 #endif /* CONFIG_IA32_EMULATION */
1137
1138 #ifdef CONFIG_X86_X32_ABI
1139 static long x32_arch_ptrace(struct task_struct *child,
1140                             compat_long_t request, compat_ulong_t caddr,
1141                             compat_ulong_t cdata)
1142 {
1143         unsigned long addr = caddr;
1144         unsigned long data = cdata;
1145         void __user *datap = compat_ptr(data);
1146         int ret;
1147
1148         switch (request) {
1149         /* Read 32bits at location addr in the USER area.  Only allow
1150            to return the lower 32bits of segment and debug registers.  */
1151         case PTRACE_PEEKUSR: {
1152                 u32 tmp;
1153
1154                 ret = -EIO;
1155                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1156                     addr < offsetof(struct user_regs_struct, cs))
1157                         break;
1158
1159                 tmp = 0;  /* Default return condition */
1160                 if (addr < sizeof(struct user_regs_struct))
1161                         tmp = getreg(child, addr);
1162                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1163                          addr <= offsetof(struct user, u_debugreg[7])) {
1164                         addr -= offsetof(struct user, u_debugreg[0]);
1165                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1166                 }
1167                 ret = put_user(tmp, (__u32 __user *)datap);
1168                 break;
1169         }
1170
1171         /* Write the word at location addr in the USER area.  Only allow
1172            to update segment and debug registers with the upper 32bits
1173            zero-extended. */
1174         case PTRACE_POKEUSR:
1175                 ret = -EIO;
1176                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1177                     addr < offsetof(struct user_regs_struct, cs))
1178                         break;
1179
1180                 if (addr < sizeof(struct user_regs_struct))
1181                         ret = putreg(child, addr, data);
1182                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1183                          addr <= offsetof(struct user, u_debugreg[7])) {
1184                         addr -= offsetof(struct user, u_debugreg[0]);
1185                         ret = ptrace_set_debugreg(child,
1186                                                   addr / sizeof(data), data);
1187                 }
1188                 break;
1189
1190         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1191                 return copy_regset_to_user(child,
1192                                            task_user_regset_view(current),
1193                                            REGSET_GENERAL,
1194                                            0, sizeof(struct user_regs_struct),
1195                                            datap);
1196
1197         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1198                 return copy_regset_from_user(child,
1199                                              task_user_regset_view(current),
1200                                              REGSET_GENERAL,
1201                                              0, sizeof(struct user_regs_struct),
1202                                              datap);
1203
1204         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1205                 return copy_regset_to_user(child,
1206                                            task_user_regset_view(current),
1207                                            REGSET_FP,
1208                                            0, sizeof(struct user_i387_struct),
1209                                            datap);
1210
1211         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1212                 return copy_regset_from_user(child,
1213                                              task_user_regset_view(current),
1214                                              REGSET_FP,
1215                                              0, sizeof(struct user_i387_struct),
1216                                              datap);
1217
1218         default:
1219                 return compat_ptrace_request(child, request, addr, data);
1220         }
1221
1222         return ret;
1223 }
1224 #endif
1225
1226 #ifdef CONFIG_COMPAT
1227 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1228                         compat_ulong_t caddr, compat_ulong_t cdata)
1229 {
1230 #ifdef CONFIG_X86_X32_ABI
1231         if (!in_ia32_syscall())
1232                 return x32_arch_ptrace(child, request, caddr, cdata);
1233 #endif
1234 #ifdef CONFIG_IA32_EMULATION
1235         return ia32_arch_ptrace(child, request, caddr, cdata);
1236 #else
1237         return 0;
1238 #endif
1239 }
1240 #endif  /* CONFIG_COMPAT */
1241
1242 #ifdef CONFIG_X86_64
1243
1244 static struct user_regset x86_64_regsets[] __ro_after_init = {
1245         [REGSET_GENERAL] = {
1246                 .core_note_type = NT_PRSTATUS,
1247                 .n = sizeof(struct user_regs_struct) / sizeof(long),
1248                 .size = sizeof(long), .align = sizeof(long),
1249                 .get = genregs_get, .set = genregs_set
1250         },
1251         [REGSET_FP] = {
1252                 .core_note_type = NT_PRFPREG,
1253                 .n = sizeof(struct user_i387_struct) / sizeof(long),
1254                 .size = sizeof(long), .align = sizeof(long),
1255                 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1256         },
1257         [REGSET_XSTATE] = {
1258                 .core_note_type = NT_X86_XSTATE,
1259                 .size = sizeof(u64), .align = sizeof(u64),
1260                 .active = xstateregs_active, .get = xstateregs_get,
1261                 .set = xstateregs_set
1262         },
1263         [REGSET_IOPERM64] = {
1264                 .core_note_type = NT_386_IOPERM,
1265                 .n = IO_BITMAP_LONGS,
1266                 .size = sizeof(long), .align = sizeof(long),
1267                 .active = ioperm_active, .get = ioperm_get
1268         },
1269 };
1270
1271 static const struct user_regset_view user_x86_64_view = {
1272         .name = "x86_64", .e_machine = EM_X86_64,
1273         .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1274 };
1275
1276 #else  /* CONFIG_X86_32 */
1277
1278 #define user_regs_struct32      user_regs_struct
1279 #define genregs32_get           genregs_get
1280 #define genregs32_set           genregs_set
1281
1282 #endif  /* CONFIG_X86_64 */
1283
1284 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1285 static struct user_regset x86_32_regsets[] __ro_after_init = {
1286         [REGSET_GENERAL] = {
1287                 .core_note_type = NT_PRSTATUS,
1288                 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1289                 .size = sizeof(u32), .align = sizeof(u32),
1290                 .get = genregs32_get, .set = genregs32_set
1291         },
1292         [REGSET_FP] = {
1293                 .core_note_type = NT_PRFPREG,
1294                 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1295                 .size = sizeof(u32), .align = sizeof(u32),
1296                 .active = regset_fpregs_active, .get = fpregs_get, .set = fpregs_set
1297         },
1298         [REGSET_XFP] = {
1299                 .core_note_type = NT_PRXFPREG,
1300                 .n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
1301                 .size = sizeof(u32), .align = sizeof(u32),
1302                 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1303         },
1304         [REGSET_XSTATE] = {
1305                 .core_note_type = NT_X86_XSTATE,
1306                 .size = sizeof(u64), .align = sizeof(u64),
1307                 .active = xstateregs_active, .get = xstateregs_get,
1308                 .set = xstateregs_set
1309         },
1310         [REGSET_TLS] = {
1311                 .core_note_type = NT_386_TLS,
1312                 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1313                 .size = sizeof(struct user_desc),
1314                 .align = sizeof(struct user_desc),
1315                 .active = regset_tls_active,
1316                 .get = regset_tls_get, .set = regset_tls_set
1317         },
1318         [REGSET_IOPERM32] = {
1319                 .core_note_type = NT_386_IOPERM,
1320                 .n = IO_BITMAP_BYTES / sizeof(u32),
1321                 .size = sizeof(u32), .align = sizeof(u32),
1322                 .active = ioperm_active, .get = ioperm_get
1323         },
1324 };
1325
1326 static const struct user_regset_view user_x86_32_view = {
1327         .name = "i386", .e_machine = EM_386,
1328         .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1329 };
1330 #endif
1331
1332 /*
1333  * This represents bytes 464..511 in the memory layout exported through
1334  * the REGSET_XSTATE interface.
1335  */
1336 u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1337
1338 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1339 {
1340 #ifdef CONFIG_X86_64
1341         x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1342 #endif
1343 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1344         x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1345 #endif
1346         xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1347 }
1348
1349 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1350 {
1351 #ifdef CONFIG_IA32_EMULATION
1352         if (!user_64bit_mode(task_pt_regs(task)))
1353 #endif
1354 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1355                 return &user_x86_32_view;
1356 #endif
1357 #ifdef CONFIG_X86_64
1358         return &user_x86_64_view;
1359 #endif
1360 }
1361
1362 void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs,
1363                                          int error_code, int si_code)
1364 {
1365         tsk->thread.trap_nr = X86_TRAP_DB;
1366         tsk->thread.error_code = error_code;
1367
1368         /* Send us the fake SIGTRAP */
1369         force_sig_fault(SIGTRAP, si_code,
1370                         user_mode(regs) ? (void __user *)regs->ip : NULL, tsk);
1371 }
1372
1373 void user_single_step_report(struct pt_regs *regs)
1374 {
1375         send_sigtrap(current, regs, 0, TRAP_BRKPT);
1376 }