arch/x86/kernel/ptrace.c

   1 /* By Ross Biro 1/23/92 */
   2 /*
   3  * Pentium III FXSR, SSE support
   4  *      Gareth Hughes <gareth@valinux.com>, May 2000
   5  *
   6  * BTS tracing
   7  *      Markus Metzger <markus.t.metzger@intel.com>, Dec 2007
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/sched.h>
  12 #include <linux/mm.h>
  13 #include <linux/smp.h>
  14 #include <linux/errno.h>
  15 #include <linux/ptrace.h>
  16 #include <linux/regset.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
  24 #include <asm/uaccess.h>
  25 #include <asm/pgtable.h>
  26 #include <asm/system.h>
  27 #include <asm/processor.h>
  28 #include <asm/i387.h>
  29 #include <asm/debugreg.h>
  30 #include <asm/ldt.h>
  31 #include <asm/desc.h>
  32 #include <asm/prctl.h>
  33 #include <asm/proto.h>
  34 #include <asm/ds.h>
  35
  36 #include "tls.h"
  37
  38 enum x86_regset {
  39         REGSET_GENERAL,
  40         REGSET_FP,
  41         REGSET_XFP,
  42         REGSET_TLS,
  43 };
  44
  45 /*
  46  * does not yet catch signals sent when the child dies.
  47  * in exit.c or in signal.c.
  48  */
  49
  50 /*
  51  * Determines which flags the user has access to [1 = access, 0 = no access].
  52  */
  53 #define FLAG_MASK_32            ((unsigned long)                        \
  54                                  (X86_EFLAGS_CF | X86_EFLAGS_PF |       \
  55                                   X86_EFLAGS_AF | X86_EFLAGS_ZF |       \
  56                                   X86_EFLAGS_SF | X86_EFLAGS_TF |       \
  57                                   X86_EFLAGS_DF | X86_EFLAGS_OF |       \
  58                                   X86_EFLAGS_RF | X86_EFLAGS_AC))
  59
  60 /*
  61  * Determines whether a value may be installed in a segment register.
  62  */
  63 static inline bool invalid_selector(u16 value)
  64 {
  65         return unlikely(value != 0 && (value & SEGMENT_RPL_MASK) != USER_RPL);
  66 }
  67
  68 #ifdef CONFIG_X86_32
  69
  70 #define FLAG_MASK               FLAG_MASK_32
  71
  72 static long *pt_regs_access(struct pt_regs *regs, unsigned long regno)
  73 {
  74         BUILD_BUG_ON(offsetof(struct pt_regs, bx) != 0);
  75         regno >>= 2;
  76         if (regno > FS)
  77                 --regno;
  78         return &regs->bx + regno;
  79 }
  80
  81 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
  82 {
  83         /*
  84          * Returning the value truncates it to 16 bits.
  85          */
  86         unsigned int retval;
  87         if (offset != offsetof(struct user_regs_struct, gs))
  88                 retval = *pt_regs_access(task_pt_regs(task), offset);
  89         else {
  90                 retval = task->thread.gs;
  91                 if (task == current)
  92                         savesegment(gs, retval);
  93         }
  94         return retval;
  95 }
  96
  97 static int set_segment_reg(struct task_struct *task,
  98                            unsigned long offset, u16 value)
  99 {
 100         /*
 101          * The value argument was already truncated to 16 bits.
 102          */
 103         if (invalid_selector(value))
 104                 return -EIO;
 105
 106         if (offset != offsetof(struct user_regs_struct, gs))
 107                 *pt_regs_access(task_pt_regs(task), offset) = value;
 108         else {
 109                 task->thread.gs = value;
 110                 if (task == current)
 111                         /*
 112                          * The user-mode %gs is not affected by
 113                          * kernel entry, so we must update the CPU.
 114                          */
 115                         loadsegment(gs, value);
 116         }
 117
 118         return 0;
 119 }
 120
 121 static unsigned long debugreg_addr_limit(struct task_struct *task)
 122 {
 123         return TASK_SIZE - 3;
 124 }
 125
 126 #else  /* CONFIG_X86_64 */
 127
 128 #define FLAG_MASK               (FLAG_MASK_32 | X86_EFLAGS_NT)
 129
 130 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
 131 {
 132         BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
 133         return &regs->r15 + (offset / sizeof(regs->r15));
 134 }
 135
 136 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 137 {
 138         /*
 139          * Returning the value truncates it to 16 bits.
 140          */
 141         unsigned int seg;
 142
 143         switch (offset) {
 144         case offsetof(struct user_regs_struct, fs):
 145                 if (task == current) {
 146                         /* Older gas can't assemble movq %?s,%r?? */
 147                         asm("movl %%fs,%0" : "=r" (seg));
 148                         return seg;
 149                 }
 150                 return task->thread.fsindex;
 151         case offsetof(struct user_regs_struct, gs):
 152                 if (task == current) {
 153                         asm("movl %%gs,%0" : "=r" (seg));
 154                         return seg;
 155                 }
 156                 return task->thread.gsindex;
 157         case offsetof(struct user_regs_struct, ds):
 158                 if (task == current) {
 159                         asm("movl %%ds,%0" : "=r" (seg));
 160                         return seg;
 161                 }
 162                 return task->thread.ds;
 163         case offsetof(struct user_regs_struct, es):
 164                 if (task == current) {
 165                         asm("movl %%es,%0" : "=r" (seg));
 166                         return seg;
 167                 }
 168                 return task->thread.es;
 169
 170         case offsetof(struct user_regs_struct, cs):
 171         case offsetof(struct user_regs_struct, ss):
 172                 break;
 173         }
 174         return *pt_regs_access(task_pt_regs(task), offset);
 175 }
 176
 177 static int set_segment_reg(struct task_struct *task,
 178                            unsigned long offset, u16 value)
 179 {
 180         /*
 181          * The value argument was already truncated to 16 bits.
 182          */
 183         if (invalid_selector(value))
 184                 return -EIO;
 185
 186         switch (offset) {
 187         case offsetof(struct user_regs_struct,fs):
 188                 /*
 189                  * If this is setting fs as for normal 64-bit use but
 190                  * setting fs_base has implicitly changed it, leave it.
 191                  */
 192                 if ((value == FS_TLS_SEL && task->thread.fsindex == 0 &&
 193                      task->thread.fs != 0) ||
 194                     (value == 0 && task->thread.fsindex == FS_TLS_SEL &&
 195                      task->thread.fs == 0))
 196                         break;
 197                 task->thread.fsindex = value;
 198                 if (task == current)
 199                         loadsegment(fs, task->thread.fsindex);
 200                 break;
 201         case offsetof(struct user_regs_struct,gs):
 202                 /*
 203                  * If this is setting gs as for normal 64-bit use but
 204                  * setting gs_base has implicitly changed it, leave it.
 205                  */
 206                 if ((value == GS_TLS_SEL && task->thread.gsindex == 0 &&
 207                      task->thread.gs != 0) ||
 208                     (value == 0 && task->thread.gsindex == GS_TLS_SEL &&
 209                      task->thread.gs == 0))
 210                         break;
 211                 task->thread.gsindex = value;
 212                 if (task == current)
 213                         load_gs_index(task->thread.gsindex);
 214                 break;
 215         case offsetof(struct user_regs_struct,ds):
 216                 task->thread.ds = value;
 217                 if (task == current)
 218                         loadsegment(ds, task->thread.ds);
 219                 break;
 220         case offsetof(struct user_regs_struct,es):
 221                 task->thread.es = value;
 222                 if (task == current)
 223                         loadsegment(es, task->thread.es);
 224                 break;
 225
 226                 /*
 227                  * Can't actually change these in 64-bit mode.
 228                  */
 229         case offsetof(struct user_regs_struct,cs):
 230 #ifdef CONFIG_IA32_EMULATION
 231                 if (test_tsk_thread_flag(task, TIF_IA32))
 232                         task_pt_regs(task)->cs = value;
 233 #endif
 234                 break;
 235         case offsetof(struct user_regs_struct,ss):
 236 #ifdef CONFIG_IA32_EMULATION
 237                 if (test_tsk_thread_flag(task, TIF_IA32))
 238                         task_pt_regs(task)->ss = value;
 239 #endif
 240                 break;
 241         }
 242
 243         return 0;
 244 }
 245
 246 static unsigned long debugreg_addr_limit(struct task_struct *task)
 247 {
 248 #ifdef CONFIG_IA32_EMULATION
 249         if (test_tsk_thread_flag(task, TIF_IA32))
 250                 return IA32_PAGE_OFFSET - 3;
 251 #endif
 252         return TASK_SIZE64 - 7;
 253 }
 254
 255 #endif  /* CONFIG_X86_32 */
 256
 257 static unsigned long get_flags(struct task_struct *task)
 258 {
 259         unsigned long retval = task_pt_regs(task)->flags;
 260
 261         /*
 262          * If the debugger set TF, hide it from the readout.
 263          */
 264         if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 265                 retval &= ~X86_EFLAGS_TF;
 266
 267         return retval;
 268 }
 269
 270 static int set_flags(struct task_struct *task, unsigned long value)
 271 {
 272         struct pt_regs *regs = task_pt_regs(task);
 273
 274         /*
 275          * If the user value contains TF, mark that
 276          * it was not "us" (the debugger) that set it.
 277          * If not, make sure it stays set if we had.
 278          */
 279         if (value & X86_EFLAGS_TF)
 280                 clear_tsk_thread_flag(task, TIF_FORCED_TF);
 281         else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 282                 value |= X86_EFLAGS_TF;
 283
 284         regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
 285
 286         return 0;
 287 }
 288
 289 static int putreg(struct task_struct *child,
 290                   unsigned long offset, unsigned long value)
 291 {
 292         switch (offset) {
 293         case offsetof(struct user_regs_struct, cs):
 294         case offsetof(struct user_regs_struct, ds):
 295         case offsetof(struct user_regs_struct, es):
 296         case offsetof(struct user_regs_struct, fs):
 297         case offsetof(struct user_regs_struct, gs):
 298         case offsetof(struct user_regs_struct, ss):
 299                 return set_segment_reg(child, offset, value);
 300
 301         case offsetof(struct user_regs_struct, flags):
 302                 return set_flags(child, value);
 303
 304 #ifdef CONFIG_X86_64
 305         case offsetof(struct user_regs_struct,fs_base):
 306                 if (value >= TASK_SIZE_OF(child))
 307                         return -EIO;
 308                 /*
 309                  * When changing the segment base, use do_arch_prctl
 310                  * to set either thread.fs or thread.fsindex and the
 311                  * corresponding GDT slot.
 312                  */
 313                 if (child->thread.fs != value)
 314                         return do_arch_prctl(child, ARCH_SET_FS, value);
 315                 return 0;
 316         case offsetof(struct user_regs_struct,gs_base):
 317                 /*
 318                  * Exactly the same here as the %fs handling above.
 319                  */
 320                 if (value >= TASK_SIZE_OF(child))
 321                         return -EIO;
 322                 if (child->thread.gs != value)
 323                         return do_arch_prctl(child, ARCH_SET_GS, value);
 324                 return 0;
 325 #endif
 326         }
 327
 328         *pt_regs_access(task_pt_regs(child), offset) = value;
 329         return 0;
 330 }
 331
 332 static unsigned long getreg(struct task_struct *task, unsigned long offset)
 333 {
 334         switch (offset) {
 335         case offsetof(struct user_regs_struct, cs):
 336         case offsetof(struct user_regs_struct, ds):
 337         case offsetof(struct user_regs_struct, es):
 338         case offsetof(struct user_regs_struct, fs):
 339         case offsetof(struct user_regs_struct, gs):
 340         case offsetof(struct user_regs_struct, ss):
 341                 return get_segment_reg(task, offset);
 342
 343         case offsetof(struct user_regs_struct, flags):
 344                 return get_flags(task);
 345
 346 #ifdef CONFIG_X86_64
 347         case offsetof(struct user_regs_struct, fs_base): {
 348                 /*
 349                  * do_arch_prctl may have used a GDT slot instead of
 350                  * the MSR.  To userland, it appears the same either
 351                  * way, except the %fs segment selector might not be 0.
 352                  */
 353                 unsigned int seg = task->thread.fsindex;
 354                 if (task->thread.fs != 0)
 355                         return task->thread.fs;
 356                 if (task == current)
 357                         asm("movl %%fs,%0" : "=r" (seg));
 358                 if (seg != FS_TLS_SEL)
 359                         return 0;
 360                 return get_desc_base(&task->thread.tls_array[FS_TLS]);
 361         }
 362         case offsetof(struct user_regs_struct, gs_base): {
 363                 /*
 364                  * Exactly the same here as the %fs handling above.
 365                  */
 366                 unsigned int seg = task->thread.gsindex;
 367                 if (task->thread.gs != 0)
 368                         return task->thread.gs;
 369                 if (task == current)
 370                         asm("movl %%gs,%0" : "=r" (seg));
 371                 if (seg != GS_TLS_SEL)
 372                         return 0;
 373                 return get_desc_base(&task->thread.tls_array[GS_TLS]);
 374         }
 375 #endif
 376         }
 377
 378         return *pt_regs_access(task_pt_regs(task), offset);
 379 }
 380
 381 static int genregs_get(struct task_struct *target,
 382                        const struct user_regset *regset,
 383                        unsigned int pos, unsigned int count,
 384                        void *kbuf, void __user *ubuf)
 385 {
 386         if (kbuf) {
 387                 unsigned long *k = kbuf;
 388                 while (count > 0) {
 389                         *k++ = getreg(target, pos);
 390                         count -= sizeof(*k);
 391                         pos += sizeof(*k);
 392                 }
 393         } else {
 394                 unsigned long __user *u = ubuf;
 395                 while (count > 0) {
 396                         if (__put_user(getreg(target, pos), u++))
 397                                 return -EFAULT;
 398                         count -= sizeof(*u);
 399                         pos += sizeof(*u);
 400                 }
 401         }
 402
 403         return 0;
 404 }
 405
 406 static int genregs_set(struct task_struct *target,
 407                        const struct user_regset *regset,
 408                        unsigned int pos, unsigned int count,
 409                        const void *kbuf, const void __user *ubuf)
 410 {
 411         int ret = 0;
 412         if (kbuf) {
 413                 const unsigned long *k = kbuf;
 414                 while (count > 0 && !ret) {
 415                         ret = putreg(target, pos, *k++);
 416                         count -= sizeof(*k);
 417                         pos += sizeof(*k);
 418                 }
 419         } else {
 420                 const unsigned long  __user *u = ubuf;
 421                 while (count > 0 && !ret) {
 422                         unsigned long word;
 423                         ret = __get_user(word, u++);
 424                         if (ret)
 425                                 break;
 426                         ret = putreg(target, pos, word);
 427                         count -= sizeof(*u);
 428                         pos += sizeof(*u);
 429                 }
 430         }
 431         return ret;
 432 }
 433
 434 /*
 435  * This function is trivial and will be inlined by the compiler.
 436  * Having it separates the implementation details of debug
 437  * registers from the interface details of ptrace.
 438  */
 439 static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
 440 {
 441         switch (n) {
 442         case 0:         return child->thread.debugreg0;
 443         case 1:         return child->thread.debugreg1;
 444         case 2:         return child->thread.debugreg2;
 445         case 3:         return child->thread.debugreg3;
 446         case 6:         return child->thread.debugreg6;
 447         case 7:         return child->thread.debugreg7;
 448         }
 449         return 0;
 450 }
 451
 452 static int ptrace_set_debugreg(struct task_struct *child,
 453                                int n, unsigned long data)
 454 {
 455         int i;
 456
 457         if (unlikely(n == 4 || n == 5))
 458                 return -EIO;
 459
 460         if (n < 4 && unlikely(data >= debugreg_addr_limit(child)))
 461                 return -EIO;
 462
 463         switch (n) {
 464         case 0:         child->thread.debugreg0 = data; break;
 465         case 1:         child->thread.debugreg1 = data; break;
 466         case 2:         child->thread.debugreg2 = data; break;
 467         case 3:         child->thread.debugreg3 = data; break;
 468
 469         case 6:
 470                 if ((data & ~0xffffffffUL) != 0)
 471                         return -EIO;
 472                 child->thread.debugreg6 = data;
 473                 break;
 474
 475         case 7:
 476                 /*
 477                  * Sanity-check data. Take one half-byte at once with
 478                  * check = (val >> (16 + 4*i)) & 0xf. It contains the
 479                  * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
 480                  * 2 and 3 are LENi. Given a list of invalid values,
 481                  * we do mask |= 1 << invalid_value, so that
 482                  * (mask >> check) & 1 is a correct test for invalid
 483                  * values.
 484                  *
 485                  * R/Wi contains the type of the breakpoint /
 486                  * watchpoint, LENi contains the length of the watched
 487                  * data in the watchpoint case.
 488                  *
 489                  * The invalid values are:
 490                  * - LENi == 0x10 (undefined), so mask |= 0x0f00.       [32-bit]
 491                  * - R/Wi == 0x10 (break on I/O reads or writes), so
 492                  *   mask |= 0x4444.
 493                  * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
 494                  *   0x1110.
 495                  *
 496                  * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
 497                  *
 498                  * See the Intel Manual "System Programming Guide",
 499                  * 15.2.4
 500                  *
 501                  * Note that LENi == 0x10 is defined on x86_64 in long
 502                  * mode (i.e. even for 32-bit userspace software, but
 503                  * 64-bit kernel), so the x86_64 mask value is 0x5454.
 504                  * See the AMD manual no. 24593 (AMD64 System Programming)
 505                  */
 506 #ifdef CONFIG_X86_32
 507 #define DR7_MASK        0x5f54
 508 #else
 509 #define DR7_MASK        0x5554
 510 #endif
 511                 data &= ~DR_CONTROL_RESERVED;
 512                 for (i = 0; i < 4; i++)
 513                         if ((DR7_MASK >> ((data >> (16 + 4*i)) & 0xf)) & 1)
 514                                 return -EIO;
 515                 child->thread.debugreg7 = data;
 516                 if (data)
 517                         set_tsk_thread_flag(child, TIF_DEBUG);
 518                 else
 519                         clear_tsk_thread_flag(child, TIF_DEBUG);
 520                 break;
 521         }
 522
 523         return 0;
 524 }
 525
 526 static int ptrace_bts_get_size(struct task_struct *child)
 527 {
 528         if (!child->thread.ds_area_msr)
 529                 return -ENXIO;
 530
 531         return ds_get_bts_index((void *)child->thread.ds_area_msr);
 532 }
 533
 534 static int ptrace_bts_read_record(struct task_struct *child,
 535                                   long index,
 536                                   struct bts_struct __user *out)
 537 {
 538         struct bts_struct ret;
 539         int retval;
 540         int bts_end;
 541         int bts_index;
 542
 543         if (!child->thread.ds_area_msr)
 544                 return -ENXIO;
 545
 546         if (index < 0)
 547                 return -EINVAL;
 548
 549         bts_end = ds_get_bts_end((void *)child->thread.ds_area_msr);
 550         if (bts_end <= index)
 551                 return -EINVAL;
 552
 553         /* translate the ptrace bts index into the ds bts index */
 554         bts_index = ds_get_bts_index((void *)child->thread.ds_area_msr);
 555         bts_index -= (index + 1);
 556         if (bts_index < 0)
 557                 bts_index += bts_end;
 558
 559         retval = ds_read_bts((void *)child->thread.ds_area_msr,
 560                              bts_index, &ret);
 561         if (retval < 0)
 562                 return retval;
 563
 564         if (copy_to_user(out, &ret, sizeof(ret)))
 565                 return -EFAULT;
 566
 567         return sizeof(ret);
 568 }
 569
 570 static int ptrace_bts_write_record(struct task_struct *child,
 571                                    const struct bts_struct *in)
 572 {
 573         int retval;
 574
 575         if (!child->thread.ds_area_msr)
 576                 return -ENXIO;
 577
 578         retval = ds_write_bts((void *)child->thread.ds_area_msr, in);
 579         if (retval)
 580                 return retval;
 581
 582         return sizeof(*in);
 583 }
 584
 585 static int ptrace_bts_clear(struct task_struct *child)
 586 {
 587         if (!child->thread.ds_area_msr)
 588                 return -ENXIO;
 589
 590         return ds_clear((void *)child->thread.ds_area_msr);
 591 }
 592
 593 static int ptrace_bts_drain(struct task_struct *child,
 594                             long size,
 595                             struct bts_struct __user *out)
 596 {
 597         int end, i;
 598         void *ds = (void *)child->thread.ds_area_msr;
 599
 600         if (!ds)
 601                 return -ENXIO;
 602
 603         end = ds_get_bts_index(ds);
 604         if (end <= 0)
 605                 return end;
 606
 607         if (size < (end * sizeof(struct bts_struct)))
 608                 return -EIO;
 609
 610         for (i = 0; i < end; i++, out++) {
 611                 struct bts_struct ret;
 612                 int retval;
 613
 614                 retval = ds_read_bts(ds, i, &ret);
 615                 if (retval < 0)
 616                         return retval;
 617
 618                 if (copy_to_user(out, &ret, sizeof(ret)))
 619                         return -EFAULT;
 620         }
 621
 622         ds_clear(ds);
 623
 624         return end;
 625 }
 626
 627 static int ptrace_bts_realloc(struct task_struct *child,
 628                               int size, int reduce_size)
 629 {
 630         unsigned long rlim, vm;
 631         int ret, old_size;
 632
 633         if (size < 0)
 634                 return -EINVAL;
 635
 636         old_size = ds_get_bts_size((void *)child->thread.ds_area_msr);
 637         if (old_size < 0)
 638                 return old_size;
 639
 640         ret = ds_free((void **)&child->thread.ds_area_msr);
 641         if (ret < 0)
 642                 goto out;
 643
 644         size >>= PAGE_SHIFT;
 645         old_size >>= PAGE_SHIFT;
 646
 647         current->mm->total_vm  -= old_size;
 648         current->mm->locked_vm -= old_size;
 649
 650         if (size == 0)
 651                 goto out;
 652
 653         rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
 654         vm = current->mm->total_vm  + size;
 655         if (rlim < vm) {
 656                 ret = -ENOMEM;
 657
 658                 if (!reduce_size)
 659                         goto out;
 660
 661                 size = rlim - current->mm->total_vm;
 662                 if (size <= 0)
 663                         goto out;
 664         }
 665
 666         rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
 667         vm = current->mm->locked_vm  + size;
 668         if (rlim < vm) {
 669                 ret = -ENOMEM;
 670
 671                 if (!reduce_size)
 672                         goto out;
 673
 674                 size = rlim - current->mm->locked_vm;
 675                 if (size <= 0)
 676                         goto out;
 677         }
 678
 679         ret = ds_allocate((void **)&child->thread.ds_area_msr,
 680                           size << PAGE_SHIFT);
 681         if (ret < 0)
 682                 goto out;
 683
 684         current->mm->total_vm  += size;
 685         current->mm->locked_vm += size;
 686
 687 out:
 688         if (child->thread.ds_area_msr)
 689                 set_tsk_thread_flag(child, TIF_DS_AREA_MSR);
 690         else
 691                 clear_tsk_thread_flag(child, TIF_DS_AREA_MSR);
 692
 693         return ret;
 694 }
 695
 696 static int ptrace_bts_config(struct task_struct *child,
 697                              long cfg_size,
 698                              const struct ptrace_bts_config __user *ucfg)
 699 {
 700         struct ptrace_bts_config cfg;
 701         int bts_size, ret = 0;
 702         void *ds;
 703
 704         if (cfg_size < sizeof(cfg))
 705                 return -EIO;
 706
 707         if (copy_from_user(&cfg, ucfg, sizeof(cfg)))
 708                 return -EFAULT;
 709
 710         if ((int)cfg.size < 0)
 711                 return -EINVAL;
 712
 713         bts_size = 0;
 714         ds = (void *)child->thread.ds_area_msr;
 715         if (ds) {
 716                 bts_size = ds_get_bts_size(ds);
 717                 if (bts_size < 0)
 718                         return bts_size;
 719         }
 720         cfg.size = PAGE_ALIGN(cfg.size);
 721
 722         if (bts_size != cfg.size) {
 723                 ret = ptrace_bts_realloc(child, cfg.size,
 724                                          cfg.flags & PTRACE_BTS_O_CUT_SIZE);
 725                 if (ret < 0)
 726                         goto errout;
 727
 728                 ds = (void *)child->thread.ds_area_msr;
 729         }
 730
 731         if (cfg.flags & PTRACE_BTS_O_SIGNAL)
 732                 ret = ds_set_overflow(ds, DS_O_SIGNAL);
 733         else
 734                 ret = ds_set_overflow(ds, DS_O_WRAP);
 735         if (ret < 0)
 736                 goto errout;
 737
 738         if (cfg.flags & PTRACE_BTS_O_TRACE)
 739                 child->thread.debugctlmsr |= ds_debugctl_mask();
 740         else
 741                 child->thread.debugctlmsr &= ~ds_debugctl_mask();
 742
 743         if (cfg.flags & PTRACE_BTS_O_SCHED)
 744                 set_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 745         else
 746                 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 747
 748         ret = sizeof(cfg);
 749
 750 out:
 751         if (child->thread.debugctlmsr)
 752                 set_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 753         else
 754                 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 755
 756         return ret;
 757
 758 errout:
 759         child->thread.debugctlmsr &= ~ds_debugctl_mask();
 760         clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 761         goto out;
 762 }
 763
 764 static int ptrace_bts_status(struct task_struct *child,
 765                              long cfg_size,
 766                              struct ptrace_bts_config __user *ucfg)
 767 {
 768         void *ds = (void *)child->thread.ds_area_msr;
 769         struct ptrace_bts_config cfg;
 770
 771         if (cfg_size < sizeof(cfg))
 772                 return -EIO;
 773
 774         memset(&cfg, 0, sizeof(cfg));
 775
 776         if (ds) {
 777                 cfg.size = ds_get_bts_size(ds);
 778
 779                 if (ds_get_overflow(ds) == DS_O_SIGNAL)
 780                         cfg.flags |= PTRACE_BTS_O_SIGNAL;
 781
 782                 if (test_tsk_thread_flag(child, TIF_DEBUGCTLMSR) &&
 783                     child->thread.debugctlmsr & ds_debugctl_mask())
 784                         cfg.flags |= PTRACE_BTS_O_TRACE;
 785
 786                 if (test_tsk_thread_flag(child, TIF_BTS_TRACE_TS))
 787                         cfg.flags |= PTRACE_BTS_O_SCHED;
 788         }
 789
 790         if (copy_to_user(ucfg, &cfg, sizeof(cfg)))
 791                 return -EFAULT;
 792
 793         return sizeof(cfg);
 794 }
 795
 796 void ptrace_bts_take_timestamp(struct task_struct *tsk,
 797                                enum bts_qualifier qualifier)
 798 {
 799         struct bts_struct rec = {
 800                 .qualifier = qualifier,
 801                 .variant.jiffies = jiffies_64
 802         };
 803
 804         ptrace_bts_write_record(tsk, &rec);
 805 }
 806
 807 /*
 808  * Called by kernel/ptrace.c when detaching..
 809  *
 810  * Make sure the single step bit is not set.
 811  */
 812 void ptrace_disable(struct task_struct *child)
 813 {
 814         user_disable_single_step(child);
 815 #ifdef TIF_SYSCALL_EMU
 816         clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 817 #endif
 818         if (child->thread.ds_area_msr) {
 819                 ptrace_bts_realloc(child, 0, 0);
 820                 child->thread.debugctlmsr &= ~ds_debugctl_mask();
 821                 if (!child->thread.debugctlmsr)
 822                         clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 823                 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 824         }
 825 }
 826
 827 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 828 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
 829 #endif
 830
 831 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 832 {
 833         int ret;
 834         unsigned long __user *datap = (unsigned long __user *)data;
 835
 836         switch (request) {
 837         /* read the word at location addr in the USER area. */
 838         case PTRACE_PEEKUSR: {
 839                 unsigned long tmp;
 840
 841                 ret = -EIO;
 842                 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
 843                     addr >= sizeof(struct user))
 844                         break;
 845
 846                 tmp = 0;  /* Default return condition */
 847                 if (addr < sizeof(struct user_regs_struct))
 848                         tmp = getreg(child, addr);
 849                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 850                          addr <= offsetof(struct user, u_debugreg[7])) {
 851                         addr -= offsetof(struct user, u_debugreg[0]);
 852                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
 853                 }
 854                 ret = put_user(tmp, datap);
 855                 break;
 856         }
 857
 858         case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 859                 ret = -EIO;
 860                 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
 861                     addr >= sizeof(struct user))
 862                         break;
 863
 864                 if (addr < sizeof(struct user_regs_struct))
 865                         ret = putreg(child, addr, data);
 866                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 867                          addr <= offsetof(struct user, u_debugreg[7])) {
 868                         addr -= offsetof(struct user, u_debugreg[0]);
 869                         ret = ptrace_set_debugreg(child,
 870                                                   addr / sizeof(data), data);
 871                 }
 872                 break;
 873
 874         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
 875                 return copy_regset_to_user(child,
 876                                            task_user_regset_view(current),
 877                                            REGSET_GENERAL,
 878                                            0, sizeof(struct user_regs_struct),
 879                                            datap);
 880
 881         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 882                 return copy_regset_from_user(child,
 883                                              task_user_regset_view(current),
 884                                              REGSET_GENERAL,
 885                                              0, sizeof(struct user_regs_struct),
 886                                              datap);
 887
 888         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
 889                 return copy_regset_to_user(child,
 890                                            task_user_regset_view(current),
 891                                            REGSET_FP,
 892                                            0, sizeof(struct user_i387_struct),
 893                                            datap);
 894
 895         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
 896                 return copy_regset_from_user(child,
 897                                              task_user_regset_view(current),
 898                                              REGSET_FP,
 899                                              0, sizeof(struct user_i387_struct),
 900                                              datap);
 901
 902 #ifdef CONFIG_X86_32
 903         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
 904                 return copy_regset_to_user(child, &user_x86_32_view,
 905                                            REGSET_XFP,
 906                                            0, sizeof(struct user_fxsr_struct),
 907                                            datap);
 908
 909         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
 910                 return copy_regset_from_user(child, &user_x86_32_view,
 911                                              REGSET_XFP,
 912                                              0, sizeof(struct user_fxsr_struct),
 913                                              datap);
 914 #endif
 915
 916 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 917         case PTRACE_GET_THREAD_AREA:
 918                 if (addr < 0)
 919                         return -EIO;
 920                 ret = do_get_thread_area(child, addr,
 921                                          (struct user_desc __user *) data);
 922                 break;
 923
 924         case PTRACE_SET_THREAD_AREA:
 925                 if (addr < 0)
 926                         return -EIO;
 927                 ret = do_set_thread_area(child, addr,
 928                                          (struct user_desc __user *) data, 0);
 929                 break;
 930 #endif
 931
 932 #ifdef CONFIG_X86_64
 933                 /* normal 64bit interface to access TLS data.
 934                    Works just like arch_prctl, except that the arguments
 935                    are reversed. */
 936         case PTRACE_ARCH_PRCTL:
 937                 ret = do_arch_prctl(child, data, addr);
 938                 break;
 939 #endif
 940
 941         case PTRACE_BTS_CONFIG:
 942                 ret = ptrace_bts_config
 943                         (child, data, (struct ptrace_bts_config __user *)addr);
 944                 break;
 945
 946         case PTRACE_BTS_STATUS:
 947                 ret = ptrace_bts_status
 948                         (child, data, (struct ptrace_bts_config __user *)addr);
 949                 break;
 950
 951         case PTRACE_BTS_SIZE:
 952                 ret = ptrace_bts_get_size(child);
 953                 break;
 954
 955         case PTRACE_BTS_GET:
 956                 ret = ptrace_bts_read_record
 957                         (child, data, (struct bts_struct __user *) addr);
 958                 break;
 959
 960         case PTRACE_BTS_CLEAR:
 961                 ret = ptrace_bts_clear(child);
 962                 break;
 963
 964         case PTRACE_BTS_DRAIN:
 965                 ret = ptrace_bts_drain
 966                         (child, data, (struct bts_struct __user *) addr);
 967                 break;
 968
 969         default:
 970                 ret = ptrace_request(child, request, addr, data);
 971                 break;
 972         }
 973
 974         return ret;
 975 }
 976
 977 #ifdef CONFIG_IA32_EMULATION
 978
 979 #include <linux/compat.h>
 980 #include <linux/syscalls.h>
 981 #include <asm/ia32.h>
 982 #include <asm/user32.h>
 983
 984 #define R32(l,q)                                                        \
 985         case offsetof(struct user32, regs.l):                           \
 986                 regs->q = value; break
 987
 988 #define SEG32(rs)                                                       \
 989         case offsetof(struct user32, regs.rs):                          \
 990                 return set_segment_reg(child,                           \
 991                                        offsetof(struct user_regs_struct, rs), \
 992                                        value);                          \
 993                 break
 994
 995 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
 996 {
 997         struct pt_regs *regs = task_pt_regs(child);
 998
 999         switch (regno) {
1000
1001         SEG32(cs);
1002         SEG32(ds);
1003         SEG32(es);
1004         SEG32(fs);
1005         SEG32(gs);
1006         SEG32(ss);
1007
1008         R32(ebx, bx);
1009         R32(ecx, cx);
1010         R32(edx, dx);
1011         R32(edi, di);
1012         R32(esi, si);
1013         R32(ebp, bp);
1014         R32(eax, ax);
1015         R32(orig_eax, orig_ax);
1016         R32(eip, ip);
1017         R32(esp, sp);
1018
1019         case offsetof(struct user32, regs.eflags):
1020                 return set_flags(child, value);
1021
1022         case offsetof(struct user32, u_debugreg[0]) ...
1023                 offsetof(struct user32, u_debugreg[7]):
1024                 regno -= offsetof(struct user32, u_debugreg[0]);
1025                 return ptrace_set_debugreg(child, regno / 4, value);
1026
1027         default:
1028                 if (regno > sizeof(struct user32) || (regno & 3))
1029                         return -EIO;
1030
1031                 /*
1032                  * Other dummy fields in the virtual user structure
1033                  * are ignored
1034                  */
1035                 break;
1036         }
1037         return 0;
1038 }
1039
1040 #undef R32
1041 #undef SEG32
1042
1043 #define R32(l,q)                                                        \
1044         case offsetof(struct user32, regs.l):                           \
1045                 *val = regs->q; break
1046
1047 #define SEG32(rs)                                                       \
1048         case offsetof(struct user32, regs.rs):                          \
1049                 *val = get_segment_reg(child,                           \
1050                                        offsetof(struct user_regs_struct, rs)); \
1051                 break
1052
1053 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
1054 {
1055         struct pt_regs *regs = task_pt_regs(child);
1056
1057         switch (regno) {
1058
1059         SEG32(ds);
1060         SEG32(es);
1061         SEG32(fs);
1062         SEG32(gs);
1063
1064         R32(cs, cs);
1065         R32(ss, ss);
1066         R32(ebx, bx);
1067         R32(ecx, cx);
1068         R32(edx, dx);
1069         R32(edi, di);
1070         R32(esi, si);
1071         R32(ebp, bp);
1072         R32(eax, ax);
1073         R32(orig_eax, orig_ax);
1074         R32(eip, ip);
1075         R32(esp, sp);
1076
1077         case offsetof(struct user32, regs.eflags):
1078                 *val = get_flags(child);
1079                 break;
1080
1081         case offsetof(struct user32, u_debugreg[0]) ...
1082                 offsetof(struct user32, u_debugreg[7]):
1083                 regno -= offsetof(struct user32, u_debugreg[0]);
1084                 *val = ptrace_get_debugreg(child, regno / 4);
1085                 break;
1086
1087         default:
1088                 if (regno > sizeof(struct user32) || (regno & 3))
1089                         return -EIO;
1090
1091                 /*
1092                  * Other dummy fields in the virtual user structure
1093                  * are ignored
1094                  */
1095                 *val = 0;
1096                 break;
1097         }
1098         return 0;
1099 }
1100
1101 #undef R32
1102 #undef SEG32
1103
1104 static int genregs32_get(struct task_struct *target,
1105                          const struct user_regset *regset,
1106                          unsigned int pos, unsigned int count,
1107                          void *kbuf, void __user *ubuf)
1108 {
1109         if (kbuf) {
1110                 compat_ulong_t *k = kbuf;
1111                 while (count > 0) {
1112                         getreg32(target, pos, k++);
1113                         count -= sizeof(*k);
1114                         pos += sizeof(*k);
1115                 }
1116         } else {
1117                 compat_ulong_t __user *u = ubuf;
1118                 while (count > 0) {
1119                         compat_ulong_t word;
1120                         getreg32(target, pos, &word);
1121                         if (__put_user(word, u++))
1122                                 return -EFAULT;
1123                         count -= sizeof(*u);
1124                         pos += sizeof(*u);
1125                 }
1126         }
1127
1128         return 0;
1129 }
1130
1131 static int genregs32_set(struct task_struct *target,
1132                          const struct user_regset *regset,
1133                          unsigned int pos, unsigned int count,
1134                          const void *kbuf, const void __user *ubuf)
1135 {
1136         int ret = 0;
1137         if (kbuf) {
1138                 const compat_ulong_t *k = kbuf;
1139                 while (count > 0 && !ret) {
1140                         ret = putreg(target, pos, *k++);
1141                         count -= sizeof(*k);
1142                         pos += sizeof(*k);
1143                 }
1144         } else {
1145                 const compat_ulong_t __user *u = ubuf;
1146                 while (count > 0 && !ret) {
1147                         compat_ulong_t word;
1148                         ret = __get_user(word, u++);
1149                         if (ret)
1150                                 break;
1151                         ret = putreg(target, pos, word);
1152                         count -= sizeof(*u);
1153                         pos += sizeof(*u);
1154                 }
1155         }
1156         return ret;
1157 }
1158
1159 static long ptrace32_siginfo(unsigned request, u32 pid, u32 addr, u32 data)
1160 {
1161         siginfo_t __user *si = compat_alloc_user_space(sizeof(siginfo_t));
1162         compat_siginfo_t __user *si32 = compat_ptr(data);
1163         siginfo_t ssi;
1164         int ret;
1165
1166         if (request == PTRACE_SETSIGINFO) {
1167                 memset(&ssi, 0, sizeof(siginfo_t));
1168                 ret = copy_siginfo_from_user32(&ssi, si32);
1169                 if (ret)
1170                         return ret;
1171                 if (copy_to_user(si, &ssi, sizeof(siginfo_t)))
1172                         return -EFAULT;
1173         }
1174         ret = sys_ptrace(request, pid, addr, (unsigned long)si);
1175         if (ret)
1176                 return ret;
1177         if (request == PTRACE_GETSIGINFO) {
1178                 if (copy_from_user(&ssi, si, sizeof(siginfo_t)))
1179                         return -EFAULT;
1180                 ret = copy_siginfo_to_user32(si32, &ssi);
1181         }
1182         return ret;
1183 }
1184
1185 asmlinkage long sys32_ptrace(long request, u32 pid, u32 addr, u32 data)
1186 {
1187         struct task_struct *child;
1188         struct pt_regs *childregs;
1189         void __user *datap = compat_ptr(data);
1190         int ret;
1191         __u32 val;
1192
1193         switch (request) {
1194         case PTRACE_TRACEME:
1195         case PTRACE_ATTACH:
1196         case PTRACE_KILL:
1197         case PTRACE_CONT:
1198         case PTRACE_SINGLESTEP:
1199         case PTRACE_SINGLEBLOCK:
1200         case PTRACE_DETACH:
1201         case PTRACE_SYSCALL:
1202         case PTRACE_OLDSETOPTIONS:
1203         case PTRACE_SETOPTIONS:
1204         case PTRACE_SET_THREAD_AREA:
1205         case PTRACE_GET_THREAD_AREA:
1206         case PTRACE_BTS_CONFIG:
1207         case PTRACE_BTS_STATUS:
1208         case PTRACE_BTS_SIZE:
1209         case PTRACE_BTS_GET:
1210         case PTRACE_BTS_CLEAR:
1211         case PTRACE_BTS_DRAIN:
1212                 return sys_ptrace(request, pid, addr, data);
1213
1214         default:
1215                 return -EINVAL;
1216
1217         case PTRACE_PEEKTEXT:
1218         case PTRACE_PEEKDATA:
1219         case PTRACE_POKEDATA:
1220         case PTRACE_POKETEXT:
1221         case PTRACE_POKEUSR:
1222         case PTRACE_PEEKUSR:
1223         case PTRACE_GETREGS:
1224         case PTRACE_SETREGS:
1225         case PTRACE_SETFPREGS:
1226         case PTRACE_GETFPREGS:
1227         case PTRACE_SETFPXREGS:
1228         case PTRACE_GETFPXREGS:
1229         case PTRACE_GETEVENTMSG:
1230                 break;
1231
1232         case PTRACE_SETSIGINFO:
1233         case PTRACE_GETSIGINFO:
1234                 return ptrace32_siginfo(request, pid, addr, data);
1235         }
1236
1237         child = ptrace_get_task_struct(pid);
1238         if (IS_ERR(child))
1239                 return PTR_ERR(child);
1240
1241         ret = ptrace_check_attach(child, request == PTRACE_KILL);
1242         if (ret < 0)
1243                 goto out;
1244
1245         childregs = task_pt_regs(child);
1246
1247         switch (request) {
1248         case PTRACE_PEEKUSR:
1249                 ret = getreg32(child, addr, &val);
1250                 if (ret == 0)
1251                         ret = put_user(val, (__u32 __user *)datap);
1252                 break;
1253
1254         case PTRACE_POKEUSR:
1255                 ret = putreg32(child, addr, data);
1256                 break;
1257
1258         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1259                 return copy_regset_to_user(child, &user_x86_32_view,
1260                                            REGSET_GENERAL,
1261                                            0, sizeof(struct user_regs_struct32),
1262                                            datap);
1263
1264         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1265                 return copy_regset_from_user(child, &user_x86_32_view,
1266                                              REGSET_GENERAL, 0,
1267                                              sizeof(struct user_regs_struct32),
1268                                              datap);
1269
1270         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1271                 return copy_regset_to_user(child, &user_x86_32_view,
1272                                            REGSET_FP, 0,
1273                                            sizeof(struct user_i387_ia32_struct),
1274                                            datap);
1275
1276         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1277                 return copy_regset_from_user(
1278                         child, &user_x86_32_view, REGSET_FP,
1279                         0, sizeof(struct user_i387_ia32_struct), datap);
1280
1281         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1282                 return copy_regset_to_user(child, &user_x86_32_view,
1283                                            REGSET_XFP, 0,
1284                                            sizeof(struct user32_fxsr_struct),
1285                                            datap);
1286
1287         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1288                 return copy_regset_from_user(child, &user_x86_32_view,
1289                                              REGSET_XFP, 0,
1290                                              sizeof(struct user32_fxsr_struct),
1291                                              datap);
1292
1293         default:
1294                 return compat_ptrace_request(child, request, addr, data);
1295         }
1296
1297  out:
1298         put_task_struct(child);
1299         return ret;
1300 }
1301
1302 #endif  /* CONFIG_IA32_EMULATION */
1303
1304 #ifdef CONFIG_X86_64
1305
1306 static const struct user_regset x86_64_regsets[] = {
1307         [REGSET_GENERAL] = {
1308                 .core_note_type = NT_PRSTATUS,
1309                 .n = sizeof(struct user_regs_struct) / sizeof(long),
1310                 .size = sizeof(long), .align = sizeof(long),
1311                 .get = genregs_get, .set = genregs_set
1312         },
1313         [REGSET_FP] = {
1314                 .core_note_type = NT_PRFPREG,
1315                 .n = sizeof(struct user_i387_struct) / sizeof(long),
1316                 .size = sizeof(long), .align = sizeof(long),
1317                 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1318         },
1319 };
1320
1321 static const struct user_regset_view user_x86_64_view = {
1322         .name = "x86_64", .e_machine = EM_X86_64,
1323         .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1324 };
1325
1326 #else  /* CONFIG_X86_32 */
1327
1328 #define user_regs_struct32      user_regs_struct
1329 #define genregs32_get           genregs_get
1330 #define genregs32_set           genregs_set
1331
1332 #endif  /* CONFIG_X86_64 */
1333
1334 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1335 static const struct user_regset x86_32_regsets[] = {
1336         [REGSET_GENERAL] = {
1337                 .core_note_type = NT_PRSTATUS,
1338                 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1339                 .size = sizeof(u32), .align = sizeof(u32),
1340                 .get = genregs32_get, .set = genregs32_set
1341         },
1342         [REGSET_FP] = {
1343                 .core_note_type = NT_PRFPREG,
1344                 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1345                 .size = sizeof(u32), .align = sizeof(u32),
1346                 .active = fpregs_active, .get = fpregs_get, .set = fpregs_set
1347         },
1348         [REGSET_XFP] = {
1349                 .core_note_type = NT_PRXFPREG,
1350                 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1351                 .size = sizeof(u32), .align = sizeof(u32),
1352                 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1353         },
1354         [REGSET_TLS] = {
1355                 .core_note_type = NT_386_TLS,
1356                 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1357                 .size = sizeof(struct user_desc),
1358                 .align = sizeof(struct user_desc),
1359                 .active = regset_tls_active,
1360                 .get = regset_tls_get, .set = regset_tls_set
1361         },
1362 };
1363
1364 static const struct user_regset_view user_x86_32_view = {
1365         .name = "i386", .e_machine = EM_386,
1366         .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1367 };
1368 #endif
1369
1370 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1371 {
1372 #ifdef CONFIG_IA32_EMULATION
1373         if (test_tsk_thread_flag(task, TIF_IA32))
1374 #endif
1375 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1376                 return &user_x86_32_view;
1377 #endif
1378 #ifdef CONFIG_X86_64
1379         return &user_x86_64_view;
1380 #endif
1381 }
1382
1383 #ifdef CONFIG_X86_32
1384
1385 void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
1386 {
1387         struct siginfo info;
1388
1389         tsk->thread.trap_no = 1;
1390         tsk->thread.error_code = error_code;
1391
1392         memset(&info, 0, sizeof(info));
1393         info.si_signo = SIGTRAP;
1394         info.si_code = TRAP_BRKPT;
1395
1396         /* User-mode ip? */
1397         info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
1398
1399         /* Send us the fake SIGTRAP */
1400         force_sig_info(SIGTRAP, &info, tsk);
1401 }
1402
1403 /* notification of system call entry/exit
1404  * - triggered by current->work.syscall_trace
1405  */
1406 __attribute__((regparm(3)))
1407 int do_syscall_trace(struct pt_regs *regs, int entryexit)
1408 {
1409         int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
1410         /*
1411          * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
1412          * interception
1413          */
1414         int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
1415         int ret = 0;
1416
1417         /* do the secure computing check first */
1418         if (!entryexit)
1419                 secure_computing(regs->orig_ax);
1420
1421         if (unlikely(current->audit_context)) {
1422                 if (entryexit)
1423                         audit_syscall_exit(AUDITSC_RESULT(regs->ax),
1424                                                 regs->ax);
1425                 /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
1426                  * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
1427                  * not used, entry.S will call us only on syscall exit, not
1428                  * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
1429                  * calling send_sigtrap() on syscall entry.
1430                  *
1431                  * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
1432                  * is_singlestep is false, despite his name, so we will still do
1433                  * the correct thing.
1434                  */
1435                 else if (is_singlestep)
1436                         goto out;
1437         }
1438
1439         if (!(current->ptrace & PT_PTRACED))
1440                 goto out;
1441
1442         /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
1443          * and then is resumed with SYSEMU_SINGLESTEP, it will come in
1444          * here. We have to check this and return */
1445         if (is_sysemu && entryexit)
1446                 return 0;
1447
1448         /* Fake a debug trap */
1449         if (is_singlestep)
1450                 send_sigtrap(current, regs, 0);
1451
1452         if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
1453                 goto out;
1454
1455         /* the 0x80 provides a way for the tracing parent to distinguish
1456            between a syscall stop and SIGTRAP delivery */
1457         /* Note that the debugger could change the result of test_thread_flag!*/
1458         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
1459
1460         /*
1461          * this isn't the same as continuing with a signal, but it will do
1462          * for normal use.  strace only continues with a signal if the
1463          * stopping signal is not SIGTRAP.  -brl
1464          */
1465         if (current->exit_code) {
1466                 send_sig(current->exit_code, current, 1);
1467                 current->exit_code = 0;
1468         }
1469         ret = is_sysemu;
1470 out:
1471         if (unlikely(current->audit_context) && !entryexit)
1472                 audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
1473                                     regs->bx, regs->cx, regs->dx, regs->si);
1474         if (ret == 0)
1475                 return 0;
1476
1477         regs->orig_ax = -1; /* force skip of syscall restarting */
1478         if (unlikely(current->audit_context))
1479                 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1480         return 1;
1481 }
1482
1483 #else  /* CONFIG_X86_64 */
1484
1485 static void syscall_trace(struct pt_regs *regs)
1486 {
1487
1488 #if 0
1489         printk("trace %s ip %lx sp %lx ax %d origrax %d caller %lx tiflags %x ptrace %x\n",
1490                current->comm,
1491                regs->ip, regs->sp, regs->ax, regs->orig_ax, __builtin_return_address(0),
1492                current_thread_info()->flags, current->ptrace);
1493 #endif
1494
1495         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
1496                                 ? 0x80 : 0));
1497         /*
1498          * this isn't the same as continuing with a signal, but it will do
1499          * for normal use.  strace only continues with a signal if the
1500          * stopping signal is not SIGTRAP.  -brl
1501          */
1502         if (current->exit_code) {
1503                 send_sig(current->exit_code, current, 1);
1504                 current->exit_code = 0;
1505         }
1506 }
1507
1508 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
1509 {
1510         /* do the secure computing check first */
1511         secure_computing(regs->orig_ax);
1512
1513         if (test_thread_flag(TIF_SYSCALL_TRACE)
1514             && (current->ptrace & PT_PTRACED))
1515                 syscall_trace(regs);
1516
1517         if (unlikely(current->audit_context)) {
1518                 if (test_thread_flag(TIF_IA32)) {
1519                         audit_syscall_entry(AUDIT_ARCH_I386,
1520                                             regs->orig_ax,
1521                                             regs->bx, regs->cx,
1522                                             regs->dx, regs->si);
1523                 } else {
1524                         audit_syscall_entry(AUDIT_ARCH_X86_64,
1525                                             regs->orig_ax,
1526                                             regs->di, regs->si,
1527                                             regs->dx, regs->r10);
1528                 }
1529         }
1530 }
1531
1532 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1533 {
1534         if (unlikely(current->audit_context))
1535                 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1536
1537         if ((test_thread_flag(TIF_SYSCALL_TRACE)
1538              || test_thread_flag(TIF_SINGLESTEP))
1539             && (current->ptrace & PT_PTRACED))
1540                 syscall_trace(regs);
1541 }
1542
1543 #endif  /* CONFIG_X86_32 */