arch/x86/kernel/ptrace.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* By Ross Biro 1/23/92 */
   3 /*
   4  * Pentium III FXSR, SSE support
   5  *      Gareth Hughes <gareth@valinux.com>, May 2000
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/sched.h>
  10 #include <linux/sched/task_stack.h>
  11 #include <linux/mm.h>
  12 #include <linux/smp.h>
  13 #include <linux/errno.h>
  14 #include <linux/slab.h>
  15 #include <linux/ptrace.h>
  16 #include <linux/tracehook.h>
  17 #include <linux/user.h>
  18 #include <linux/elf.h>
  19 #include <linux/security.h>
  20 #include <linux/audit.h>
  21 #include <linux/seccomp.h>
  22 #include <linux/signal.h>
  23 #include <linux/perf_event.h>
  24 #include <linux/hw_breakpoint.h>
  25 #include <linux/rcupdate.h>
  26 #include <linux/export.h>
  27 #include <linux/context_tracking.h>
  28 #include <linux/nospec.h>
  29
  30 #include <linux/uaccess.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/processor.h>
  33 #include <asm/fpu/internal.h>
  34 #include <asm/fpu/signal.h>
  35 #include <asm/fpu/regset.h>
  36 #include <asm/debugreg.h>
  37 #include <asm/ldt.h>
  38 #include <asm/desc.h>
  39 #include <asm/prctl.h>
  40 #include <asm/proto.h>
  41 #include <asm/hw_breakpoint.h>
  42 #include <asm/traps.h>
  43 #include <asm/syscall.h>
  44 #include <asm/fsgsbase.h>
  45 #include <asm/io_bitmap.h>
  46
  47 #include "tls.h"
  48
  49 enum x86_regset {
  50         REGSET_GENERAL,
  51         REGSET_FP,
  52         REGSET_XFP,
  53         REGSET_IOPERM64 = REGSET_XFP,
  54         REGSET_XSTATE,
  55         REGSET_TLS,
  56         REGSET_IOPERM32,
  57 };
  58
  59 struct pt_regs_offset {
  60         const char *name;
  61         int offset;
  62 };
  63
  64 #define REG_OFFSET_NAME(r) {.name = #r, .offset = offsetof(struct pt_regs, r)}
  65 #define REG_OFFSET_END {.name = NULL, .offset = 0}
  66
  67 static const struct pt_regs_offset regoffset_table[] = {
  68 #ifdef CONFIG_X86_64
  69         REG_OFFSET_NAME(r15),
  70         REG_OFFSET_NAME(r14),
  71         REG_OFFSET_NAME(r13),
  72         REG_OFFSET_NAME(r12),
  73         REG_OFFSET_NAME(r11),
  74         REG_OFFSET_NAME(r10),
  75         REG_OFFSET_NAME(r9),
  76         REG_OFFSET_NAME(r8),
  77 #endif
  78         REG_OFFSET_NAME(bx),
  79         REG_OFFSET_NAME(cx),
  80         REG_OFFSET_NAME(dx),
  81         REG_OFFSET_NAME(si),
  82         REG_OFFSET_NAME(di),
  83         REG_OFFSET_NAME(bp),
  84         REG_OFFSET_NAME(ax),
  85 #ifdef CONFIG_X86_32
  86         REG_OFFSET_NAME(ds),
  87         REG_OFFSET_NAME(es),
  88         REG_OFFSET_NAME(fs),
  89         REG_OFFSET_NAME(gs),
  90 #endif
  91         REG_OFFSET_NAME(orig_ax),
  92         REG_OFFSET_NAME(ip),
  93         REG_OFFSET_NAME(cs),
  94         REG_OFFSET_NAME(flags),
  95         REG_OFFSET_NAME(sp),
  96         REG_OFFSET_NAME(ss),
  97         REG_OFFSET_END,
  98 };
  99
 100 /**
 101  * regs_query_register_offset() - query register offset from its name
 102  * @name:       the name of a register
 103  *
 104  * regs_query_register_offset() returns the offset of a register in struct
 105  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
 106  */
 107 int regs_query_register_offset(const char *name)
 108 {
 109         const struct pt_regs_offset *roff;
 110         for (roff = regoffset_table; roff->name != NULL; roff++)
 111                 if (!strcmp(roff->name, name))
 112                         return roff->offset;
 113         return -EINVAL;
 114 }
 115
 116 /**
 117  * regs_query_register_name() - query register name from its offset
 118  * @offset:     the offset of a register in struct pt_regs.
 119  *
 120  * regs_query_register_name() returns the name of a register from its
 121  * offset in struct pt_regs. If the @offset is invalid, this returns NULL;
 122  */
 123 const char *regs_query_register_name(unsigned int offset)
 124 {
 125         const struct pt_regs_offset *roff;
 126         for (roff = regoffset_table; roff->name != NULL; roff++)
 127                 if (roff->offset == offset)
 128                         return roff->name;
 129         return NULL;
 130 }
 131
 132 /*
 133  * does not yet catch signals sent when the child dies.
 134  * in exit.c or in signal.c.
 135  */
 136
 137 /*
 138  * Determines which flags the user has access to [1 = access, 0 = no access].
 139  */
 140 #define FLAG_MASK_32            ((unsigned long)                        \
 141                                  (X86_EFLAGS_CF | X86_EFLAGS_PF |       \
 142                                   X86_EFLAGS_AF | X86_EFLAGS_ZF |       \
 143                                   X86_EFLAGS_SF | X86_EFLAGS_TF |       \
 144                                   X86_EFLAGS_DF | X86_EFLAGS_OF |       \
 145                                   X86_EFLAGS_RF | X86_EFLAGS_AC))
 146
 147 /*
 148  * Determines whether a value may be installed in a segment register.
 149  */
 150 static inline bool invalid_selector(u16 value)
 151 {
 152         return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
 153 }
 154
 155 #ifdef CONFIG_X86_32
 156
 157 #define FLAG_MASK               FLAG_MASK_32
 158
 159 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
 160 {
 161         BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
 162         return &regs->bx + (regno >> 2);
 163 }
 164
 165 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 166 {
 167         /*
 168          * Returning the value truncates it to 16 bits.
 169          */
 170         unsigned int retval;
 171         if (offset != offsetof(struct user_regs_struct, gs))
 172                 retval = *pt_regs_access(task_pt_regs(task), offset);
 173         else {
 174                 if (task == current)
 175                         retval = get_user_gs(task_pt_regs(task));
 176                 else
 177                         retval = task_user_gs(task);
 178         }
 179         return retval;
 180 }
 181
 182 static int set_segment_reg(struct task_struct *task,
 183                            unsigned long offset, u16 value)
 184 {
 185         /*
 186          * The value argument was already truncated to 16 bits.
 187          */
 188         if (invalid_selector(value))
 189                 return -EIO;
 190
 191         /*
 192          * For %cs and %ss we cannot permit a null selector.
 193          * We can permit a bogus selector as long as it has USER_RPL.
 194          * Null selectors are fine for other segment registers, but
 195          * we will never get back to user mode with invalid %cs or %ss
 196          * and will take the trap in iret instead.  Much code relies
 197          * on user_mode() to distinguish a user trap frame (which can
 198          * safely use invalid selectors) from a kernel trap frame.
 199          */
 200         switch (offset) {
 201         case offsetof(struct user_regs_struct, cs):
 202         case offsetof(struct user_regs_struct, ss):
 203                 if (unlikely(value == 0))
 204                         return -EIO;
 205                 /* Else, fall through */
 206
 207         default:
 208                 *pt_regs_access(task_pt_regs(task), offset) = value;
 209                 break;
 210
 211         case offsetof(struct user_regs_struct, gs):
 212                 if (task == current)
 213                         set_user_gs(task_pt_regs(task), value);
 214                 else
 215                         task_user_gs(task) = value;
 216         }
 217
 218         return 0;
 219 }
 220
 221 #else  /* CONFIG_X86_64 */
 222
 223 #define FLAG_MASK               (FLAG_MASK_32 | X86_EFLAGS_NT)
 224
 225 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
 226 {
 227         BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
 228         return &regs->r15 + (offset / sizeof(regs->r15));
 229 }
 230
 231 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 232 {
 233         /*
 234          * Returning the value truncates it to 16 bits.
 235          */
 236         unsigned int seg;
 237
 238         switch (offset) {
 239         case offsetof(struct user_regs_struct, fs):
 240                 if (task == current) {
 241                         /* Older gas can't assemble movq %?s,%r?? */
 242                         asm("movl %%fs,%0" : "=r" (seg));
 243                         return seg;
 244                 }
 245                 return task->thread.fsindex;
 246         case offsetof(struct user_regs_struct, gs):
 247                 if (task == current) {
 248                         asm("movl %%gs,%0" : "=r" (seg));
 249                         return seg;
 250                 }
 251                 return task->thread.gsindex;
 252         case offsetof(struct user_regs_struct, ds):
 253                 if (task == current) {
 254                         asm("movl %%ds,%0" : "=r" (seg));
 255                         return seg;
 256                 }
 257                 return task->thread.ds;
 258         case offsetof(struct user_regs_struct, es):
 259                 if (task == current) {
 260                         asm("movl %%es,%0" : "=r" (seg));
 261                         return seg;
 262                 }
 263                 return task->thread.es;
 264
 265         case offsetof(struct user_regs_struct, cs):
 266         case offsetof(struct user_regs_struct, ss):
 267                 break;
 268         }
 269         return *pt_regs_access(task_pt_regs(task), offset);
 270 }
 271
 272 static int set_segment_reg(struct task_struct *task,
 273                            unsigned long offset, u16 value)
 274 {
 275         /*
 276          * The value argument was already truncated to 16 bits.
 277          */
 278         if (invalid_selector(value))
 279                 return -EIO;
 280
 281         switch (offset) {
 282         case offsetof(struct user_regs_struct,fs):
 283                 task->thread.fsindex = value;
 284                 if (task == current)
 285                         loadsegment(fs, task->thread.fsindex);
 286                 break;
 287         case offsetof(struct user_regs_struct,gs):
 288                 task->thread.gsindex = value;
 289                 if (task == current)
 290                         load_gs_index(task->thread.gsindex);
 291                 break;
 292         case offsetof(struct user_regs_struct,ds):
 293                 task->thread.ds = value;
 294                 if (task == current)
 295                         loadsegment(ds, task->thread.ds);
 296                 break;
 297         case offsetof(struct user_regs_struct,es):
 298                 task->thread.es = value;
 299                 if (task == current)
 300                         loadsegment(es, task->thread.es);
 301                 break;
 302
 303                 /*
 304                  * Can't actually change these in 64-bit mode.
 305                  */
 306         case offsetof(struct user_regs_struct,cs):
 307                 if (unlikely(value == 0))
 308                         return -EIO;
 309                 task_pt_regs(task)->cs = value;
 310                 break;
 311         case offsetof(struct user_regs_struct,ss):
 312                 if (unlikely(value == 0))
 313                         return -EIO;
 314                 task_pt_regs(task)->ss = value;
 315                 break;
 316         }
 317
 318         return 0;
 319 }
 320
 321 #endif  /* CONFIG_X86_32 */
 322
 323 static unsigned long get_flags(struct task_struct *task)
 324 {
 325         unsigned long retval = task_pt_regs(task)->flags;
 326
 327         /*
 328          * If the debugger set TF, hide it from the readout.
 329          */
 330         if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 331                 retval &= ~X86_EFLAGS_TF;
 332
 333         return retval;
 334 }
 335
 336 static int set_flags(struct task_struct *task, unsigned long value)
 337 {
 338         struct pt_regs *regs = task_pt_regs(task);
 339
 340         /*
 341          * If the user value contains TF, mark that
 342          * it was not "us" (the debugger) that set it.
 343          * If not, make sure it stays set if we had.
 344          */
 345         if (value & X86_EFLAGS_TF)
 346                 clear_tsk_thread_flag(task, TIF_FORCED_TF);
 347         else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 348                 value |= X86_EFLAGS_TF;
 349
 350         regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
 351
 352         return 0;
 353 }
 354
 355 static int putreg(struct task_struct *child,
 356                   unsigned long offset, unsigned long value)
 357 {
 358         switch (offset) {
 359         case offsetof(struct user_regs_struct, cs):
 360         case offsetof(struct user_regs_struct, ds):
 361         case offsetof(struct user_regs_struct, es):
 362         case offsetof(struct user_regs_struct, fs):
 363         case offsetof(struct user_regs_struct, gs):
 364         case offsetof(struct user_regs_struct, ss):
 365                 return set_segment_reg(child, offset, value);
 366
 367         case offsetof(struct user_regs_struct, flags):
 368                 return set_flags(child, value);
 369
 370 #ifdef CONFIG_X86_64
 371         case offsetof(struct user_regs_struct,fs_base):
 372                 if (value >= TASK_SIZE_MAX)
 373                         return -EIO;
 374                 /*
 375                  * When changing the FS base, use do_arch_prctl_64()
 376                  * to set the index to zero and to set the base
 377                  * as requested.
 378                  */
 379                 if (child->thread.fsbase != value)
 380                         return do_arch_prctl_64(child, ARCH_SET_FS, value);
 381                 return 0;
 382         case offsetof(struct user_regs_struct,gs_base):
 383                 /*
 384                  * Exactly the same here as the %fs handling above.
 385                  */
 386                 if (value >= TASK_SIZE_MAX)
 387                         return -EIO;
 388                 if (child->thread.gsbase != value)
 389                         return do_arch_prctl_64(child, ARCH_SET_GS, value);
 390                 return 0;
 391 #endif
 392         }
 393
 394         *pt_regs_access(task_pt_regs(child), offset) = value;
 395         return 0;
 396 }
 397
 398 static unsigned long getreg(struct task_struct *task, unsigned long offset)
 399 {
 400         switch (offset) {
 401         case offsetof(struct user_regs_struct, cs):
 402         case offsetof(struct user_regs_struct, ds):
 403         case offsetof(struct user_regs_struct, es):
 404         case offsetof(struct user_regs_struct, fs):
 405         case offsetof(struct user_regs_struct, gs):
 406         case offsetof(struct user_regs_struct, ss):
 407                 return get_segment_reg(task, offset);
 408
 409         case offsetof(struct user_regs_struct, flags):
 410                 return get_flags(task);
 411
 412 #ifdef CONFIG_X86_64
 413         case offsetof(struct user_regs_struct, fs_base):
 414                 return x86_fsbase_read_task(task);
 415         case offsetof(struct user_regs_struct, gs_base):
 416                 return x86_gsbase_read_task(task);
 417 #endif
 418         }
 419
 420         return *pt_regs_access(task_pt_regs(task), offset);
 421 }
 422
 423 static int genregs_get(struct task_struct *target,
 424                        const struct user_regset *regset,
 425                        unsigned int pos, unsigned int count,
 426                        void *kbuf, void __user *ubuf)
 427 {
 428         if (kbuf) {
 429                 unsigned long *k = kbuf;
 430                 while (count >= sizeof(*k)) {
 431                         *k++ = getreg(target, pos);
 432                         count -= sizeof(*k);
 433                         pos += sizeof(*k);
 434                 }
 435         } else {
 436                 unsigned long __user *u = ubuf;
 437                 while (count >= sizeof(*u)) {
 438                         if (__put_user(getreg(target, pos), u++))
 439                                 return -EFAULT;
 440                         count -= sizeof(*u);
 441                         pos += sizeof(*u);
 442                 }
 443         }
 444
 445         return 0;
 446 }
 447
 448 static int genregs_set(struct task_struct *target,
 449                        const struct user_regset *regset,
 450                        unsigned int pos, unsigned int count,
 451                        const void *kbuf, const void __user *ubuf)
 452 {
 453         int ret = 0;
 454         if (kbuf) {
 455                 const unsigned long *k = kbuf;
 456                 while (count >= sizeof(*k) && !ret) {
 457                         ret = putreg(target, pos, *k++);
 458                         count -= sizeof(*k);
 459                         pos += sizeof(*k);
 460                 }
 461         } else {
 462                 const unsigned long  __user *u = ubuf;
 463                 while (count >= sizeof(*u) && !ret) {
 464                         unsigned long word;
 465                         ret = __get_user(word, u++);
 466                         if (ret)
 467                                 break;
 468                         ret = putreg(target, pos, word);
 469                         count -= sizeof(*u);
 470                         pos += sizeof(*u);
 471                 }
 472         }
 473         return ret;
 474 }
 475
 476 static void ptrace_triggered(struct perf_event *bp,
 477                              struct perf_sample_data *data,
 478                              struct pt_regs *regs)
 479 {
 480         int i;
 481         struct thread_struct *thread = &(current->thread);
 482
 483         /*
 484          * Store in the virtual DR6 register the fact that the breakpoint
 485          * was hit so the thread's debugger will see it.
 486          */
 487         for (i = 0; i < HBP_NUM; i++) {
 488                 if (thread->ptrace_bps[i] == bp)
 489                         break;
 490         }
 491
 492         thread->debugreg6 |= (DR_TRAP0 << i);
 493 }
 494
 495 /*
 496  * Walk through every ptrace breakpoints for this thread and
 497  * build the dr7 value on top of their attributes.
 498  *
 499  */
 500 static unsigned long ptrace_get_dr7(struct perf_event *bp[])
 501 {
 502         int i;
 503         int dr7 = 0;
 504         struct arch_hw_breakpoint *info;
 505
 506         for (i = 0; i < HBP_NUM; i++) {
 507                 if (bp[i] && !bp[i]->attr.disabled) {
 508                         info = counter_arch_bp(bp[i]);
 509                         dr7 |= encode_dr7(i, info->len, info->type);
 510                 }
 511         }
 512
 513         return dr7;
 514 }
 515
 516 static int ptrace_fill_bp_fields(struct perf_event_attr *attr,
 517                                         int len, int type, bool disabled)
 518 {
 519         int err, bp_len, bp_type;
 520
 521         err = arch_bp_generic_fields(len, type, &bp_len, &bp_type);
 522         if (!err) {
 523                 attr->bp_len = bp_len;
 524                 attr->bp_type = bp_type;
 525                 attr->disabled = disabled;
 526         }
 527
 528         return err;
 529 }
 530
 531 static struct perf_event *
 532 ptrace_register_breakpoint(struct task_struct *tsk, int len, int type,
 533                                 unsigned long addr, bool disabled)
 534 {
 535         struct perf_event_attr attr;
 536         int err;
 537
 538         ptrace_breakpoint_init(&attr);
 539         attr.bp_addr = addr;
 540
 541         err = ptrace_fill_bp_fields(&attr, len, type, disabled);
 542         if (err)
 543                 return ERR_PTR(err);
 544
 545         return register_user_hw_breakpoint(&attr, ptrace_triggered,
 546                                                  NULL, tsk);
 547 }
 548
 549 static int ptrace_modify_breakpoint(struct perf_event *bp, int len, int type,
 550                                         int disabled)
 551 {
 552         struct perf_event_attr attr = bp->attr;
 553         int err;
 554
 555         err = ptrace_fill_bp_fields(&attr, len, type, disabled);
 556         if (err)
 557                 return err;
 558
 559         return modify_user_hw_breakpoint(bp, &attr);
 560 }
 561
 562 /*
 563  * Handle ptrace writes to debug register 7.
 564  */
 565 static int ptrace_write_dr7(struct task_struct *tsk, unsigned long data)
 566 {
 567         struct thread_struct *thread = &tsk->thread;
 568         unsigned long old_dr7;
 569         bool second_pass = false;
 570         int i, rc, ret = 0;
 571
 572         data &= ~DR_CONTROL_RESERVED;
 573         old_dr7 = ptrace_get_dr7(thread->ptrace_bps);
 574
 575 restore:
 576         rc = 0;
 577         for (i = 0; i < HBP_NUM; i++) {
 578                 unsigned len, type;
 579                 bool disabled = !decode_dr7(data, i, &len, &type);
 580                 struct perf_event *bp = thread->ptrace_bps[i];
 581
 582                 if (!bp) {
 583                         if (disabled)
 584                                 continue;
 585
 586                         bp = ptrace_register_breakpoint(tsk,
 587                                         len, type, 0, disabled);
 588                         if (IS_ERR(bp)) {
 589                                 rc = PTR_ERR(bp);
 590                                 break;
 591                         }
 592
 593                         thread->ptrace_bps[i] = bp;
 594                         continue;
 595                 }
 596
 597                 rc = ptrace_modify_breakpoint(bp, len, type, disabled);
 598                 if (rc)
 599                         break;
 600         }
 601
 602         /* Restore if the first pass failed, second_pass shouldn't fail. */
 603         if (rc && !WARN_ON(second_pass)) {
 604                 ret = rc;
 605                 data = old_dr7;
 606                 second_pass = true;
 607                 goto restore;
 608         }
 609
 610         return ret;
 611 }
 612
 613 /*
 614  * Handle PTRACE_PEEKUSR calls for the debug register area.
 615  */
 616 static unsigned long ptrace_get_debugreg(struct task_struct *tsk, int n)
 617 {
 618         struct thread_struct *thread = &tsk->thread;
 619         unsigned long val = 0;
 620
 621         if (n < HBP_NUM) {
 622                 int index = array_index_nospec(n, HBP_NUM);
 623                 struct perf_event *bp = thread->ptrace_bps[index];
 624
 625                 if (bp)
 626                         val = bp->hw.info.address;
 627         } else if (n == 6) {
 628                 val = thread->debugreg6;
 629         } else if (n == 7) {
 630                 val = thread->ptrace_dr7;
 631         }
 632         return val;
 633 }
 634
 635 static int ptrace_set_breakpoint_addr(struct task_struct *tsk, int nr,
 636                                       unsigned long addr)
 637 {
 638         struct thread_struct *t = &tsk->thread;
 639         struct perf_event *bp = t->ptrace_bps[nr];
 640         int err = 0;
 641
 642         if (!bp) {
 643                 /*
 644                  * Put stub len and type to create an inactive but correct bp.
 645                  *
 646                  * CHECKME: the previous code returned -EIO if the addr wasn't
 647                  * a valid task virtual addr. The new one will return -EINVAL in
 648                  *  this case.
 649                  * -EINVAL may be what we want for in-kernel breakpoints users,
 650                  * but -EIO looks better for ptrace, since we refuse a register
 651                  * writing for the user. And anyway this is the previous
 652                  * behaviour.
 653                  */
 654                 bp = ptrace_register_breakpoint(tsk,
 655                                 X86_BREAKPOINT_LEN_1, X86_BREAKPOINT_WRITE,
 656                                 addr, true);
 657                 if (IS_ERR(bp))
 658                         err = PTR_ERR(bp);
 659                 else
 660                         t->ptrace_bps[nr] = bp;
 661         } else {
 662                 struct perf_event_attr attr = bp->attr;
 663
 664                 attr.bp_addr = addr;
 665                 err = modify_user_hw_breakpoint(bp, &attr);
 666         }
 667
 668         return err;
 669 }
 670
 671 /*
 672  * Handle PTRACE_POKEUSR calls for the debug register area.
 673  */
 674 static int ptrace_set_debugreg(struct task_struct *tsk, int n,
 675                                unsigned long val)
 676 {
 677         struct thread_struct *thread = &tsk->thread;
 678         /* There are no DR4 or DR5 registers */
 679         int rc = -EIO;
 680
 681         if (n < HBP_NUM) {
 682                 rc = ptrace_set_breakpoint_addr(tsk, n, val);
 683         } else if (n == 6) {
 684                 thread->debugreg6 = val;
 685                 rc = 0;
 686         } else if (n == 7) {
 687                 rc = ptrace_write_dr7(tsk, val);
 688                 if (!rc)
 689                         thread->ptrace_dr7 = val;
 690         }
 691         return rc;
 692 }
 693
 694 /*
 695  * These access the current or another (stopped) task's io permission
 696  * bitmap for debugging or core dump.
 697  */
 698 static int ioperm_active(struct task_struct *target,
 699                          const struct user_regset *regset)
 700 {
 701         struct io_bitmap *iobm = target->thread.io_bitmap;
 702
 703         return iobm ? DIV_ROUND_UP(iobm->max, regset->size) : 0;
 704 }
 705
 706 static int ioperm_get(struct task_struct *target,
 707                       const struct user_regset *regset,
 708                       unsigned int pos, unsigned int count,
 709                       void *kbuf, void __user *ubuf)
 710 {
 711         struct io_bitmap *iobm = target->thread.io_bitmap;
 712
 713         if (!iobm)
 714                 return -ENXIO;
 715
 716         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 717                                    iobm->bitmap, 0, IO_BITMAP_BYTES);
 718 }
 719
 720 /*
 721  * Called by kernel/ptrace.c when detaching..
 722  *
 723  * Make sure the single step bit is not set.
 724  */
 725 void ptrace_disable(struct task_struct *child)
 726 {
 727         user_disable_single_step(child);
 728 }
 729
 730 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 731 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
 732 #endif
 733
 734 long arch_ptrace(struct task_struct *child, long request,
 735                  unsigned long addr, unsigned long data)
 736 {
 737         int ret;
 738         unsigned long __user *datap = (unsigned long __user *)data;
 739
 740         switch (request) {
 741         /* read the word at location addr in the USER area. */
 742         case PTRACE_PEEKUSR: {
 743                 unsigned long tmp;
 744
 745                 ret = -EIO;
 746                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 747                         break;
 748
 749                 tmp = 0;  /* Default return condition */
 750                 if (addr < sizeof(struct user_regs_struct))
 751                         tmp = getreg(child, addr);
 752                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 753                          addr <= offsetof(struct user, u_debugreg[7])) {
 754                         addr -= offsetof(struct user, u_debugreg[0]);
 755                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
 756                 }
 757                 ret = put_user(tmp, datap);
 758                 break;
 759         }
 760
 761         case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 762                 ret = -EIO;
 763                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user))
 764                         break;
 765
 766                 if (addr < sizeof(struct user_regs_struct))
 767                         ret = putreg(child, addr, data);
 768                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 769                          addr <= offsetof(struct user, u_debugreg[7])) {
 770                         addr -= offsetof(struct user, u_debugreg[0]);
 771                         ret = ptrace_set_debugreg(child,
 772                                                   addr / sizeof(data), data);
 773                 }
 774                 break;
 775
 776         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
 777                 return copy_regset_to_user(child,
 778                                            task_user_regset_view(current),
 779                                            REGSET_GENERAL,
 780                                            0, sizeof(struct user_regs_struct),
 781                                            datap);
 782
 783         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 784                 return copy_regset_from_user(child,
 785                                              task_user_regset_view(current),
 786                                              REGSET_GENERAL,
 787                                              0, sizeof(struct user_regs_struct),
 788                                              datap);
 789
 790         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
 791                 return copy_regset_to_user(child,
 792                                            task_user_regset_view(current),
 793                                            REGSET_FP,
 794                                            0, sizeof(struct user_i387_struct),
 795                                            datap);
 796
 797         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
 798                 return copy_regset_from_user(child,
 799                                              task_user_regset_view(current),
 800                                              REGSET_FP,
 801                                              0, sizeof(struct user_i387_struct),
 802                                              datap);
 803
 804 #ifdef CONFIG_X86_32
 805         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
 806                 return copy_regset_to_user(child, &user_x86_32_view,
 807                                            REGSET_XFP,
 808                                            0, sizeof(struct user_fxsr_struct),
 809                                            datap) ? -EIO : 0;
 810
 811         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
 812                 return copy_regset_from_user(child, &user_x86_32_view,
 813                                              REGSET_XFP,
 814                                              0, sizeof(struct user_fxsr_struct),
 815                                              datap) ? -EIO : 0;
 816 #endif
 817
 818 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 819         case PTRACE_GET_THREAD_AREA:
 820                 if ((int) addr < 0)
 821                         return -EIO;
 822                 ret = do_get_thread_area(child, addr,
 823                                         (struct user_desc __user *)data);
 824                 break;
 825
 826         case PTRACE_SET_THREAD_AREA:
 827                 if ((int) addr < 0)
 828                         return -EIO;
 829                 ret = do_set_thread_area(child, addr,
 830                                         (struct user_desc __user *)data, 0);
 831                 break;
 832 #endif
 833
 834 #ifdef CONFIG_X86_64
 835                 /* normal 64bit interface to access TLS data.
 836                    Works just like arch_prctl, except that the arguments
 837                    are reversed. */
 838         case PTRACE_ARCH_PRCTL:
 839                 ret = do_arch_prctl_64(child, data, addr);
 840                 break;
 841 #endif
 842
 843         default:
 844                 ret = ptrace_request(child, request, addr, data);
 845                 break;
 846         }
 847
 848         return ret;
 849 }
 850
 851 #ifdef CONFIG_IA32_EMULATION
 852
 853 #include <linux/compat.h>
 854 #include <linux/syscalls.h>
 855 #include <asm/ia32.h>
 856 #include <asm/user32.h>
 857
 858 #define R32(l,q)                                                        \
 859         case offsetof(struct user32, regs.l):                           \
 860                 regs->q = value; break
 861
 862 #define SEG32(rs)                                                       \
 863         case offsetof(struct user32, regs.rs):                          \
 864                 return set_segment_reg(child,                           \
 865                                        offsetof(struct user_regs_struct, rs), \
 866                                        value);                          \
 867                 break
 868
 869 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
 870 {
 871         struct pt_regs *regs = task_pt_regs(child);
 872
 873         switch (regno) {
 874
 875         SEG32(cs);
 876         SEG32(ds);
 877         SEG32(es);
 878         SEG32(fs);
 879         SEG32(gs);
 880         SEG32(ss);
 881
 882         R32(ebx, bx);
 883         R32(ecx, cx);
 884         R32(edx, dx);
 885         R32(edi, di);
 886         R32(esi, si);
 887         R32(ebp, bp);
 888         R32(eax, ax);
 889         R32(eip, ip);
 890         R32(esp, sp);
 891
 892         case offsetof(struct user32, regs.orig_eax):
 893                 /*
 894                  * Warning: bizarre corner case fixup here.  A 32-bit
 895                  * debugger setting orig_eax to -1 wants to disable
 896                  * syscall restart.  Make sure that the syscall
 897                  * restart code sign-extends orig_ax.  Also make sure
 898                  * we interpret the -ERESTART* codes correctly if
 899                  * loaded into regs->ax in case the task is not
 900                  * actually still sitting at the exit from a 32-bit
 901                  * syscall with TS_COMPAT still set.
 902                  */
 903                 regs->orig_ax = value;
 904                 if (syscall_get_nr(child, regs) >= 0)
 905                         child->thread_info.status |= TS_I386_REGS_POKED;
 906                 break;
 907
 908         case offsetof(struct user32, regs.eflags):
 909                 return set_flags(child, value);
 910
 911         case offsetof(struct user32, u_debugreg[0]) ...
 912                 offsetof(struct user32, u_debugreg[7]):
 913                 regno -= offsetof(struct user32, u_debugreg[0]);
 914                 return ptrace_set_debugreg(child, regno / 4, value);
 915
 916         default:
 917                 if (regno > sizeof(struct user32) || (regno & 3))
 918                         return -EIO;
 919
 920                 /*
 921                  * Other dummy fields in the virtual user structure
 922                  * are ignored
 923                  */
 924                 break;
 925         }
 926         return 0;
 927 }
 928
 929 #undef R32
 930 #undef SEG32
 931
 932 #define R32(l,q)                                                        \
 933         case offsetof(struct user32, regs.l):                           \
 934                 *val = regs->q; break
 935
 936 #define SEG32(rs)                                                       \
 937         case offsetof(struct user32, regs.rs):                          \
 938                 *val = get_segment_reg(child,                           \
 939                                        offsetof(struct user_regs_struct, rs)); \
 940                 break
 941
 942 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
 943 {
 944         struct pt_regs *regs = task_pt_regs(child);
 945
 946         switch (regno) {
 947
 948         SEG32(ds);
 949         SEG32(es);
 950         SEG32(fs);
 951         SEG32(gs);
 952
 953         R32(cs, cs);
 954         R32(ss, ss);
 955         R32(ebx, bx);
 956         R32(ecx, cx);
 957         R32(edx, dx);
 958         R32(edi, di);
 959         R32(esi, si);
 960         R32(ebp, bp);
 961         R32(eax, ax);
 962         R32(orig_eax, orig_ax);
 963         R32(eip, ip);
 964         R32(esp, sp);
 965
 966         case offsetof(struct user32, regs.eflags):
 967                 *val = get_flags(child);
 968                 break;
 969
 970         case offsetof(struct user32, u_debugreg[0]) ...
 971                 offsetof(struct user32, u_debugreg[7]):
 972                 regno -= offsetof(struct user32, u_debugreg[0]);
 973                 *val = ptrace_get_debugreg(child, regno / 4);
 974                 break;
 975
 976         default:
 977                 if (regno > sizeof(struct user32) || (regno & 3))
 978                         return -EIO;
 979
 980                 /*
 981                  * Other dummy fields in the virtual user structure
 982                  * are ignored
 983                  */
 984                 *val = 0;
 985                 break;
 986         }
 987         return 0;
 988 }
 989
 990 #undef R32
 991 #undef SEG32
 992
 993 static int genregs32_get(struct task_struct *target,
 994                          const struct user_regset *regset,
 995                          unsigned int pos, unsigned int count,
 996                          void *kbuf, void __user *ubuf)
 997 {
 998         if (kbuf) {
 999                 compat_ulong_t *k = kbuf;
1000                 while (count >= sizeof(*k)) {
1001                         getreg32(target, pos, k++);
1002                         count -= sizeof(*k);
1003                         pos += sizeof(*k);
1004                 }
1005         } else {
1006                 compat_ulong_t __user *u = ubuf;
1007                 while (count >= sizeof(*u)) {
1008                         compat_ulong_t word;
1009                         getreg32(target, pos, &word);
1010                         if (__put_user(word, u++))
1011                                 return -EFAULT;
1012                         count -= sizeof(*u);
1013                         pos += sizeof(*u);
1014                 }
1015         }
1016
1017         return 0;
1018 }
1019
1020 static int genregs32_set(struct task_struct *target,
1021                          const struct user_regset *regset,
1022                          unsigned int pos, unsigned int count,
1023                          const void *kbuf, const void __user *ubuf)
1024 {
1025         int ret = 0;
1026         if (kbuf) {
1027                 const compat_ulong_t *k = kbuf;
1028                 while (count >= sizeof(*k) && !ret) {
1029                         ret = putreg32(target, pos, *k++);
1030                         count -= sizeof(*k);
1031                         pos += sizeof(*k);
1032                 }
1033         } else {
1034                 const compat_ulong_t __user *u = ubuf;
1035                 while (count >= sizeof(*u) && !ret) {
1036                         compat_ulong_t word;
1037                         ret = __get_user(word, u++);
1038                         if (ret)
1039                                 break;
1040                         ret = putreg32(target, pos, word);
1041                         count -= sizeof(*u);
1042                         pos += sizeof(*u);
1043                 }
1044         }
1045         return ret;
1046 }
1047
1048 static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
1049                              compat_ulong_t caddr, compat_ulong_t cdata)
1050 {
1051         unsigned long addr = caddr;
1052         unsigned long data = cdata;
1053         void __user *datap = compat_ptr(data);
1054         int ret;
1055         __u32 val;
1056
1057         switch (request) {
1058         case PTRACE_PEEKUSR:
1059                 ret = getreg32(child, addr, &val);
1060                 if (ret == 0)
1061                         ret = put_user(val, (__u32 __user *)datap);
1062                 break;
1063
1064         case PTRACE_POKEUSR:
1065                 ret = putreg32(child, addr, data);
1066                 break;
1067
1068         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1069                 return copy_regset_to_user(child, &user_x86_32_view,
1070                                            REGSET_GENERAL,
1071                                            0, sizeof(struct user_regs_struct32),
1072                                            datap);
1073
1074         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1075                 return copy_regset_from_user(child, &user_x86_32_view,
1076                                              REGSET_GENERAL, 0,
1077                                              sizeof(struct user_regs_struct32),
1078                                              datap);
1079
1080         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1081                 return copy_regset_to_user(child, &user_x86_32_view,
1082                                            REGSET_FP, 0,
1083                                            sizeof(struct user_i387_ia32_struct),
1084                                            datap);
1085
1086         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1087                 return copy_regset_from_user(
1088                         child, &user_x86_32_view, REGSET_FP,
1089                         0, sizeof(struct user_i387_ia32_struct), datap);
1090
1091         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1092                 return copy_regset_to_user(child, &user_x86_32_view,
1093                                            REGSET_XFP, 0,
1094                                            sizeof(struct user32_fxsr_struct),
1095                                            datap);
1096
1097         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1098                 return copy_regset_from_user(child, &user_x86_32_view,
1099                                              REGSET_XFP, 0,
1100                                              sizeof(struct user32_fxsr_struct),
1101                                              datap);
1102
1103         case PTRACE_GET_THREAD_AREA:
1104         case PTRACE_SET_THREAD_AREA:
1105                 return arch_ptrace(child, request, addr, data);
1106
1107         default:
1108                 return compat_ptrace_request(child, request, addr, data);
1109         }
1110
1111         return ret;
1112 }
1113 #endif /* CONFIG_IA32_EMULATION */
1114
1115 #ifdef CONFIG_X86_X32_ABI
1116 static long x32_arch_ptrace(struct task_struct *child,
1117                             compat_long_t request, compat_ulong_t caddr,
1118                             compat_ulong_t cdata)
1119 {
1120         unsigned long addr = caddr;
1121         unsigned long data = cdata;
1122         void __user *datap = compat_ptr(data);
1123         int ret;
1124
1125         switch (request) {
1126         /* Read 32bits at location addr in the USER area.  Only allow
1127            to return the lower 32bits of segment and debug registers.  */
1128         case PTRACE_PEEKUSR: {
1129                 u32 tmp;
1130
1131                 ret = -EIO;
1132                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1133                     addr < offsetof(struct user_regs_struct, cs))
1134                         break;
1135
1136                 tmp = 0;  /* Default return condition */
1137                 if (addr < sizeof(struct user_regs_struct))
1138                         tmp = getreg(child, addr);
1139                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1140                          addr <= offsetof(struct user, u_debugreg[7])) {
1141                         addr -= offsetof(struct user, u_debugreg[0]);
1142                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
1143                 }
1144                 ret = put_user(tmp, (__u32 __user *)datap);
1145                 break;
1146         }
1147
1148         /* Write the word at location addr in the USER area.  Only allow
1149            to update segment and debug registers with the upper 32bits
1150            zero-extended. */
1151         case PTRACE_POKEUSR:
1152                 ret = -EIO;
1153                 if ((addr & (sizeof(data) - 1)) || addr >= sizeof(struct user) ||
1154                     addr < offsetof(struct user_regs_struct, cs))
1155                         break;
1156
1157                 if (addr < sizeof(struct user_regs_struct))
1158                         ret = putreg(child, addr, data);
1159                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
1160                          addr <= offsetof(struct user, u_debugreg[7])) {
1161                         addr -= offsetof(struct user, u_debugreg[0]);
1162                         ret = ptrace_set_debugreg(child,
1163                                                   addr / sizeof(data), data);
1164                 }
1165                 break;
1166
1167         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1168                 return copy_regset_to_user(child,
1169                                            task_user_regset_view(current),
1170                                            REGSET_GENERAL,
1171                                            0, sizeof(struct user_regs_struct),
1172                                            datap);
1173
1174         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1175                 return copy_regset_from_user(child,
1176                                              task_user_regset_view(current),
1177                                              REGSET_GENERAL,
1178                                              0, sizeof(struct user_regs_struct),
1179                                              datap);
1180
1181         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1182                 return copy_regset_to_user(child,
1183                                            task_user_regset_view(current),
1184                                            REGSET_FP,
1185                                            0, sizeof(struct user_i387_struct),
1186                                            datap);
1187
1188         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1189                 return copy_regset_from_user(child,
1190                                              task_user_regset_view(current),
1191                                              REGSET_FP,
1192                                              0, sizeof(struct user_i387_struct),
1193                                              datap);
1194
1195         default:
1196                 return compat_ptrace_request(child, request, addr, data);
1197         }
1198
1199         return ret;
1200 }
1201 #endif
1202
1203 #ifdef CONFIG_COMPAT
1204 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
1205                         compat_ulong_t caddr, compat_ulong_t cdata)
1206 {
1207 #ifdef CONFIG_X86_X32_ABI
1208         if (!in_ia32_syscall())
1209                 return x32_arch_ptrace(child, request, caddr, cdata);
1210 #endif
1211 #ifdef CONFIG_IA32_EMULATION
1212         return ia32_arch_ptrace(child, request, caddr, cdata);
1213 #else
1214         return 0;
1215 #endif
1216 }
1217 #endif  /* CONFIG_COMPAT */
1218
1219 #ifdef CONFIG_X86_64
1220
1221 static struct user_regset x86_64_regsets[] __ro_after_init = {
1222         [REGSET_GENERAL] = {
1223                 .core_note_type = NT_PRSTATUS,
1224                 .n = sizeof(struct user_regs_struct) / sizeof(long),
1225                 .size = sizeof(long), .align = sizeof(long),
1226                 .get = genregs_get, .set = genregs_set
1227         },
1228         [REGSET_FP] = {
1229                 .core_note_type = NT_PRFPREG,
1230                 .n = sizeof(struct user_i387_struct) / sizeof(long),
1231                 .size = sizeof(long), .align = sizeof(long),
1232                 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1233         },
1234         [REGSET_XSTATE] = {
1235                 .core_note_type = NT_X86_XSTATE,
1236                 .size = sizeof(u64), .align = sizeof(u64),
1237                 .active = xstateregs_active, .get = xstateregs_get,
1238                 .set = xstateregs_set
1239         },
1240         [REGSET_IOPERM64] = {
1241                 .core_note_type = NT_386_IOPERM,
1242                 .n = IO_BITMAP_LONGS,
1243                 .size = sizeof(long), .align = sizeof(long),
1244                 .active = ioperm_active, .get = ioperm_get
1245         },
1246 };
1247
1248 static const struct user_regset_view user_x86_64_view = {
1249         .name = "x86_64", .e_machine = EM_X86_64,
1250         .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1251 };
1252
1253 #else  /* CONFIG_X86_32 */
1254
1255 #define user_regs_struct32      user_regs_struct
1256 #define genregs32_get           genregs_get
1257 #define genregs32_set           genregs_set
1258
1259 #endif  /* CONFIG_X86_64 */
1260
1261 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1262 static struct user_regset x86_32_regsets[] __ro_after_init = {
1263         [REGSET_GENERAL] = {
1264                 .core_note_type = NT_PRSTATUS,
1265                 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1266                 .size = sizeof(u32), .align = sizeof(u32),
1267                 .get = genregs32_get, .set = genregs32_set
1268         },
1269         [REGSET_FP] = {
1270                 .core_note_type = NT_PRFPREG,
1271                 .n = sizeof(struct user_i387_ia32_struct) / sizeof(u32),
1272                 .size = sizeof(u32), .align = sizeof(u32),
1273                 .active = regset_fpregs_active, .get = fpregs_get, .set = fpregs_set
1274         },
1275         [REGSET_XFP] = {
1276                 .core_note_type = NT_PRXFPREG,
1277                 .n = sizeof(struct user32_fxsr_struct) / sizeof(u32),
1278                 .size = sizeof(u32), .align = sizeof(u32),
1279                 .active = regset_xregset_fpregs_active, .get = xfpregs_get, .set = xfpregs_set
1280         },
1281         [REGSET_XSTATE] = {
1282                 .core_note_type = NT_X86_XSTATE,
1283                 .size = sizeof(u64), .align = sizeof(u64),
1284                 .active = xstateregs_active, .get = xstateregs_get,
1285                 .set = xstateregs_set
1286         },
1287         [REGSET_TLS] = {
1288                 .core_note_type = NT_386_TLS,
1289                 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1290                 .size = sizeof(struct user_desc),
1291                 .align = sizeof(struct user_desc),
1292                 .active = regset_tls_active,
1293                 .get = regset_tls_get, .set = regset_tls_set
1294         },
1295         [REGSET_IOPERM32] = {
1296                 .core_note_type = NT_386_IOPERM,
1297                 .n = IO_BITMAP_BYTES / sizeof(u32),
1298                 .size = sizeof(u32), .align = sizeof(u32),
1299                 .active = ioperm_active, .get = ioperm_get
1300         },
1301 };
1302
1303 static const struct user_regset_view user_x86_32_view = {
1304         .name = "i386", .e_machine = EM_386,
1305         .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1306 };
1307 #endif
1308
1309 /*
1310  * This represents bytes 464..511 in the memory layout exported through
1311  * the REGSET_XSTATE interface.
1312  */
1313 u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS];
1314
1315 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask)
1316 {
1317 #ifdef CONFIG_X86_64
1318         x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1319 #endif
1320 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1321         x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64);
1322 #endif
1323         xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask;
1324 }
1325
1326 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1327 {
1328 #ifdef CONFIG_IA32_EMULATION
1329         if (!user_64bit_mode(task_pt_regs(task)))
1330 #endif
1331 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1332                 return &user_x86_32_view;
1333 #endif
1334 #ifdef CONFIG_X86_64
1335         return &user_x86_64_view;
1336 #endif
1337 }
1338
1339 void send_sigtrap(struct pt_regs *regs, int error_code, int si_code)
1340 {
1341         struct task_struct *tsk = current;
1342
1343         tsk->thread.trap_nr = X86_TRAP_DB;
1344         tsk->thread.error_code = error_code;
1345
1346         /* Send us the fake SIGTRAP */
1347         force_sig_fault(SIGTRAP, si_code,
1348                         user_mode(regs) ? (void __user *)regs->ip : NULL);
1349 }
1350
1351 void user_single_step_report(struct pt_regs *regs)
1352 {
1353         send_sigtrap(regs, 0, TRAP_BRKPT);
1354 }