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