err.no Git - linux-2.6/blob - 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         /*
 107          * For %cs and %ss we cannot permit a null selector.
 108          * We can permit a bogus selector as long as it has USER_RPL.
 109          * Null selectors are fine for other segment registers, but
 110          * we will never get back to user mode with invalid %cs or %ss
 111          * and will take the trap in iret instead.  Much code relies
 112          * on user_mode() to distinguish a user trap frame (which can
 113          * safely use invalid selectors) from a kernel trap frame.
 114          */
 115         switch (offset) {
 116         case offsetof(struct user_regs_struct, cs):
 117         case offsetof(struct user_regs_struct, ss):
 118                 if (unlikely(value == 0))
 119                         return -EIO;
 120
 121         default:
 122                 *pt_regs_access(task_pt_regs(task), offset) = value;
 123                 break;
 124
 125         case offsetof(struct user_regs_struct, gs):
 126                 task->thread.gs = value;
 127                 if (task == current)
 128                         /*
 129                          * The user-mode %gs is not affected by
 130                          * kernel entry, so we must update the CPU.
 131                          */
 132                         loadsegment(gs, value);
 133         }
 134
 135         return 0;
 136 }
 137
 138 static unsigned long debugreg_addr_limit(struct task_struct *task)
 139 {
 140         return TASK_SIZE - 3;
 141 }
 142
 143 #else  /* CONFIG_X86_64 */
 144
 145 #define FLAG_MASK               (FLAG_MASK_32 | X86_EFLAGS_NT)
 146
 147 static unsigned long *pt_regs_access(struct pt_regs *regs, unsigned long offset)
 148 {
 149         BUILD_BUG_ON(offsetof(struct pt_regs, r15) != 0);
 150         return &regs->r15 + (offset / sizeof(regs->r15));
 151 }
 152
 153 static u16 get_segment_reg(struct task_struct *task, unsigned long offset)
 154 {
 155         /*
 156          * Returning the value truncates it to 16 bits.
 157          */
 158         unsigned int seg;
 159
 160         switch (offset) {
 161         case offsetof(struct user_regs_struct, fs):
 162                 if (task == current) {
 163                         /* Older gas can't assemble movq %?s,%r?? */
 164                         asm("movl %%fs,%0" : "=r" (seg));
 165                         return seg;
 166                 }
 167                 return task->thread.fsindex;
 168         case offsetof(struct user_regs_struct, gs):
 169                 if (task == current) {
 170                         asm("movl %%gs,%0" : "=r" (seg));
 171                         return seg;
 172                 }
 173                 return task->thread.gsindex;
 174         case offsetof(struct user_regs_struct, ds):
 175                 if (task == current) {
 176                         asm("movl %%ds,%0" : "=r" (seg));
 177                         return seg;
 178                 }
 179                 return task->thread.ds;
 180         case offsetof(struct user_regs_struct, es):
 181                 if (task == current) {
 182                         asm("movl %%es,%0" : "=r" (seg));
 183                         return seg;
 184                 }
 185                 return task->thread.es;
 186
 187         case offsetof(struct user_regs_struct, cs):
 188         case offsetof(struct user_regs_struct, ss):
 189                 break;
 190         }
 191         return *pt_regs_access(task_pt_regs(task), offset);
 192 }
 193
 194 static int set_segment_reg(struct task_struct *task,
 195                            unsigned long offset, u16 value)
 196 {
 197         /*
 198          * The value argument was already truncated to 16 bits.
 199          */
 200         if (invalid_selector(value))
 201                 return -EIO;
 202
 203         switch (offset) {
 204         case offsetof(struct user_regs_struct,fs):
 205                 /*
 206                  * If this is setting fs as for normal 64-bit use but
 207                  * setting fs_base has implicitly changed it, leave it.
 208                  */
 209                 if ((value == FS_TLS_SEL && task->thread.fsindex == 0 &&
 210                      task->thread.fs != 0) ||
 211                     (value == 0 && task->thread.fsindex == FS_TLS_SEL &&
 212                      task->thread.fs == 0))
 213                         break;
 214                 task->thread.fsindex = value;
 215                 if (task == current)
 216                         loadsegment(fs, task->thread.fsindex);
 217                 break;
 218         case offsetof(struct user_regs_struct,gs):
 219                 /*
 220                  * If this is setting gs as for normal 64-bit use but
 221                  * setting gs_base has implicitly changed it, leave it.
 222                  */
 223                 if ((value == GS_TLS_SEL && task->thread.gsindex == 0 &&
 224                      task->thread.gs != 0) ||
 225                     (value == 0 && task->thread.gsindex == GS_TLS_SEL &&
 226                      task->thread.gs == 0))
 227                         break;
 228                 task->thread.gsindex = value;
 229                 if (task == current)
 230                         load_gs_index(task->thread.gsindex);
 231                 break;
 232         case offsetof(struct user_regs_struct,ds):
 233                 task->thread.ds = value;
 234                 if (task == current)
 235                         loadsegment(ds, task->thread.ds);
 236                 break;
 237         case offsetof(struct user_regs_struct,es):
 238                 task->thread.es = value;
 239                 if (task == current)
 240                         loadsegment(es, task->thread.es);
 241                 break;
 242
 243                 /*
 244                  * Can't actually change these in 64-bit mode.
 245                  */
 246         case offsetof(struct user_regs_struct,cs):
 247                 if (unlikely(value == 0))
 248                         return -EIO;
 249 #ifdef CONFIG_IA32_EMULATION
 250                 if (test_tsk_thread_flag(task, TIF_IA32))
 251                         task_pt_regs(task)->cs = value;
 252 #endif
 253                 break;
 254         case offsetof(struct user_regs_struct,ss):
 255                 if (unlikely(value == 0))
 256                         return -EIO;
 257 #ifdef CONFIG_IA32_EMULATION
 258                 if (test_tsk_thread_flag(task, TIF_IA32))
 259                         task_pt_regs(task)->ss = value;
 260 #endif
 261                 break;
 262         }
 263
 264         return 0;
 265 }
 266
 267 static unsigned long debugreg_addr_limit(struct task_struct *task)
 268 {
 269 #ifdef CONFIG_IA32_EMULATION
 270         if (test_tsk_thread_flag(task, TIF_IA32))
 271                 return IA32_PAGE_OFFSET - 3;
 272 #endif
 273         return TASK_SIZE64 - 7;
 274 }
 275
 276 #endif  /* CONFIG_X86_32 */
 277
 278 static unsigned long get_flags(struct task_struct *task)
 279 {
 280         unsigned long retval = task_pt_regs(task)->flags;
 281
 282         /*
 283          * If the debugger set TF, hide it from the readout.
 284          */
 285         if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 286                 retval &= ~X86_EFLAGS_TF;
 287
 288         return retval;
 289 }
 290
 291 static int set_flags(struct task_struct *task, unsigned long value)
 292 {
 293         struct pt_regs *regs = task_pt_regs(task);
 294
 295         /*
 296          * If the user value contains TF, mark that
 297          * it was not "us" (the debugger) that set it.
 298          * If not, make sure it stays set if we had.
 299          */
 300         if (value & X86_EFLAGS_TF)
 301                 clear_tsk_thread_flag(task, TIF_FORCED_TF);
 302         else if (test_tsk_thread_flag(task, TIF_FORCED_TF))
 303                 value |= X86_EFLAGS_TF;
 304
 305         regs->flags = (regs->flags & ~FLAG_MASK) | (value & FLAG_MASK);
 306
 307         return 0;
 308 }
 309
 310 static int putreg(struct task_struct *child,
 311                   unsigned long offset, unsigned long value)
 312 {
 313         switch (offset) {
 314         case offsetof(struct user_regs_struct, cs):
 315         case offsetof(struct user_regs_struct, ds):
 316         case offsetof(struct user_regs_struct, es):
 317         case offsetof(struct user_regs_struct, fs):
 318         case offsetof(struct user_regs_struct, gs):
 319         case offsetof(struct user_regs_struct, ss):
 320                 return set_segment_reg(child, offset, value);
 321
 322         case offsetof(struct user_regs_struct, flags):
 323                 return set_flags(child, value);
 324
 325 #ifdef CONFIG_X86_64
 326         /*
 327          * Orig_ax is really just a flag with small positive and
 328          * negative values, so make sure to always sign-extend it
 329          * from 32 bits so that it works correctly regardless of
 330          * whether we come from a 32-bit environment or not.
 331          */
 332         case offsetof(struct user_regs_struct, orig_ax):
 333                 value = (long) (s32) value;
 334                 break;
 335
 336         case offsetof(struct user_regs_struct,fs_base):
 337                 if (value >= TASK_SIZE_OF(child))
 338                         return -EIO;
 339                 /*
 340                  * When changing the segment base, use do_arch_prctl
 341                  * to set either thread.fs or thread.fsindex and the
 342                  * corresponding GDT slot.
 343                  */
 344                 if (child->thread.fs != value)
 345                         return do_arch_prctl(child, ARCH_SET_FS, value);
 346                 return 0;
 347         case offsetof(struct user_regs_struct,gs_base):
 348                 /*
 349                  * Exactly the same here as the %fs handling above.
 350                  */
 351                 if (value >= TASK_SIZE_OF(child))
 352                         return -EIO;
 353                 if (child->thread.gs != value)
 354                         return do_arch_prctl(child, ARCH_SET_GS, value);
 355                 return 0;
 356 #endif
 357         }
 358
 359         *pt_regs_access(task_pt_regs(child), offset) = value;
 360         return 0;
 361 }
 362
 363 static unsigned long getreg(struct task_struct *task, unsigned long offset)
 364 {
 365         switch (offset) {
 366         case offsetof(struct user_regs_struct, cs):
 367         case offsetof(struct user_regs_struct, ds):
 368         case offsetof(struct user_regs_struct, es):
 369         case offsetof(struct user_regs_struct, fs):
 370         case offsetof(struct user_regs_struct, gs):
 371         case offsetof(struct user_regs_struct, ss):
 372                 return get_segment_reg(task, offset);
 373
 374         case offsetof(struct user_regs_struct, flags):
 375                 return get_flags(task);
 376
 377 #ifdef CONFIG_X86_64
 378         case offsetof(struct user_regs_struct, fs_base): {
 379                 /*
 380                  * do_arch_prctl may have used a GDT slot instead of
 381                  * the MSR.  To userland, it appears the same either
 382                  * way, except the %fs segment selector might not be 0.
 383                  */
 384                 unsigned int seg = task->thread.fsindex;
 385                 if (task->thread.fs != 0)
 386                         return task->thread.fs;
 387                 if (task == current)
 388                         asm("movl %%fs,%0" : "=r" (seg));
 389                 if (seg != FS_TLS_SEL)
 390                         return 0;
 391                 return get_desc_base(&task->thread.tls_array[FS_TLS]);
 392         }
 393         case offsetof(struct user_regs_struct, gs_base): {
 394                 /*
 395                  * Exactly the same here as the %fs handling above.
 396                  */
 397                 unsigned int seg = task->thread.gsindex;
 398                 if (task->thread.gs != 0)
 399                         return task->thread.gs;
 400                 if (task == current)
 401                         asm("movl %%gs,%0" : "=r" (seg));
 402                 if (seg != GS_TLS_SEL)
 403                         return 0;
 404                 return get_desc_base(&task->thread.tls_array[GS_TLS]);
 405         }
 406 #endif
 407         }
 408
 409         return *pt_regs_access(task_pt_regs(task), offset);
 410 }
 411
 412 static int genregs_get(struct task_struct *target,
 413                        const struct user_regset *regset,
 414                        unsigned int pos, unsigned int count,
 415                        void *kbuf, void __user *ubuf)
 416 {
 417         if (kbuf) {
 418                 unsigned long *k = kbuf;
 419                 while (count > 0) {
 420                         *k++ = getreg(target, pos);
 421                         count -= sizeof(*k);
 422                         pos += sizeof(*k);
 423                 }
 424         } else {
 425                 unsigned long __user *u = ubuf;
 426                 while (count > 0) {
 427                         if (__put_user(getreg(target, pos), u++))
 428                                 return -EFAULT;
 429                         count -= sizeof(*u);
 430                         pos += sizeof(*u);
 431                 }
 432         }
 433
 434         return 0;
 435 }
 436
 437 static int genregs_set(struct task_struct *target,
 438                        const struct user_regset *regset,
 439                        unsigned int pos, unsigned int count,
 440                        const void *kbuf, const void __user *ubuf)
 441 {
 442         int ret = 0;
 443         if (kbuf) {
 444                 const unsigned long *k = kbuf;
 445                 while (count > 0 && !ret) {
 446                         ret = putreg(target, pos, *k++);
 447                         count -= sizeof(*k);
 448                         pos += sizeof(*k);
 449                 }
 450         } else {
 451                 const unsigned long  __user *u = ubuf;
 452                 while (count > 0 && !ret) {
 453                         unsigned long word;
 454                         ret = __get_user(word, u++);
 455                         if (ret)
 456                                 break;
 457                         ret = putreg(target, pos, word);
 458                         count -= sizeof(*u);
 459                         pos += sizeof(*u);
 460                 }
 461         }
 462         return ret;
 463 }
 464
 465 /*
 466  * This function is trivial and will be inlined by the compiler.
 467  * Having it separates the implementation details of debug
 468  * registers from the interface details of ptrace.
 469  */
 470 static unsigned long ptrace_get_debugreg(struct task_struct *child, int n)
 471 {
 472         switch (n) {
 473         case 0:         return child->thread.debugreg0;
 474         case 1:         return child->thread.debugreg1;
 475         case 2:         return child->thread.debugreg2;
 476         case 3:         return child->thread.debugreg3;
 477         case 6:         return child->thread.debugreg6;
 478         case 7:         return child->thread.debugreg7;
 479         }
 480         return 0;
 481 }
 482
 483 static int ptrace_set_debugreg(struct task_struct *child,
 484                                int n, unsigned long data)
 485 {
 486         int i;
 487
 488         if (unlikely(n == 4 || n == 5))
 489                 return -EIO;
 490
 491         if (n < 4 && unlikely(data >= debugreg_addr_limit(child)))
 492                 return -EIO;
 493
 494         switch (n) {
 495         case 0:         child->thread.debugreg0 = data; break;
 496         case 1:         child->thread.debugreg1 = data; break;
 497         case 2:         child->thread.debugreg2 = data; break;
 498         case 3:         child->thread.debugreg3 = data; break;
 499
 500         case 6:
 501                 if ((data & ~0xffffffffUL) != 0)
 502                         return -EIO;
 503                 child->thread.debugreg6 = data;
 504                 break;
 505
 506         case 7:
 507                 /*
 508                  * Sanity-check data. Take one half-byte at once with
 509                  * check = (val >> (16 + 4*i)) & 0xf. It contains the
 510                  * R/Wi and LENi bits; bits 0 and 1 are R/Wi, and bits
 511                  * 2 and 3 are LENi. Given a list of invalid values,
 512                  * we do mask |= 1 << invalid_value, so that
 513                  * (mask >> check) & 1 is a correct test for invalid
 514                  * values.
 515                  *
 516                  * R/Wi contains the type of the breakpoint /
 517                  * watchpoint, LENi contains the length of the watched
 518                  * data in the watchpoint case.
 519                  *
 520                  * The invalid values are:
 521                  * - LENi == 0x10 (undefined), so mask |= 0x0f00.       [32-bit]
 522                  * - R/Wi == 0x10 (break on I/O reads or writes), so
 523                  *   mask |= 0x4444.
 524                  * - R/Wi == 0x00 && LENi != 0x00, so we have mask |=
 525                  *   0x1110.
 526                  *
 527                  * Finally, mask = 0x0f00 | 0x4444 | 0x1110 == 0x5f54.
 528                  *
 529                  * See the Intel Manual "System Programming Guide",
 530                  * 15.2.4
 531                  *
 532                  * Note that LENi == 0x10 is defined on x86_64 in long
 533                  * mode (i.e. even for 32-bit userspace software, but
 534                  * 64-bit kernel), so the x86_64 mask value is 0x5454.
 535                  * See the AMD manual no. 24593 (AMD64 System Programming)
 536                  */
 537 #ifdef CONFIG_X86_32
 538 #define DR7_MASK        0x5f54
 539 #else
 540 #define DR7_MASK        0x5554
 541 #endif
 542                 data &= ~DR_CONTROL_RESERVED;
 543                 for (i = 0; i < 4; i++)
 544                         if ((DR7_MASK >> ((data >> (16 + 4*i)) & 0xf)) & 1)
 545                                 return -EIO;
 546                 child->thread.debugreg7 = data;
 547                 if (data)
 548                         set_tsk_thread_flag(child, TIF_DEBUG);
 549                 else
 550                         clear_tsk_thread_flag(child, TIF_DEBUG);
 551                 break;
 552         }
 553
 554         return 0;
 555 }
 556
 557 #ifdef X86_BTS
 558
 559 static int ptrace_bts_get_size(struct task_struct *child)
 560 {
 561         if (!child->thread.ds_area_msr)
 562                 return -ENXIO;
 563
 564         return ds_get_bts_index((void *)child->thread.ds_area_msr);
 565 }
 566
 567 static int ptrace_bts_read_record(struct task_struct *child,
 568                                   long index,
 569                                   struct bts_struct __user *out)
 570 {
 571         struct bts_struct ret;
 572         int retval;
 573         int bts_end;
 574         int bts_index;
 575
 576         if (!child->thread.ds_area_msr)
 577                 return -ENXIO;
 578
 579         if (index < 0)
 580                 return -EINVAL;
 581
 582         bts_end = ds_get_bts_end((void *)child->thread.ds_area_msr);
 583         if (bts_end <= index)
 584                 return -EINVAL;
 585
 586         /* translate the ptrace bts index into the ds bts index */
 587         bts_index = ds_get_bts_index((void *)child->thread.ds_area_msr);
 588         bts_index -= (index + 1);
 589         if (bts_index < 0)
 590                 bts_index += bts_end;
 591
 592         retval = ds_read_bts((void *)child->thread.ds_area_msr,
 593                              bts_index, &ret);
 594         if (retval < 0)
 595                 return retval;
 596
 597         if (copy_to_user(out, &ret, sizeof(ret)))
 598                 return -EFAULT;
 599
 600         return sizeof(ret);
 601 }
 602
 603 static int ptrace_bts_write_record(struct task_struct *child,
 604                                    const struct bts_struct *in)
 605 {
 606         int retval;
 607
 608         if (!child->thread.ds_area_msr)
 609                 return -ENXIO;
 610
 611         retval = ds_write_bts((void *)child->thread.ds_area_msr, in);
 612         if (retval)
 613                 return retval;
 614
 615         return sizeof(*in);
 616 }
 617
 618 static int ptrace_bts_clear(struct task_struct *child)
 619 {
 620         if (!child->thread.ds_area_msr)
 621                 return -ENXIO;
 622
 623         return ds_clear((void *)child->thread.ds_area_msr);
 624 }
 625
 626 static int ptrace_bts_drain(struct task_struct *child,
 627                             long size,
 628                             struct bts_struct __user *out)
 629 {
 630         int end, i;
 631         void *ds = (void *)child->thread.ds_area_msr;
 632
 633         if (!ds)
 634                 return -ENXIO;
 635
 636         end = ds_get_bts_index(ds);
 637         if (end <= 0)
 638                 return end;
 639
 640         if (size < (end * sizeof(struct bts_struct)))
 641                 return -EIO;
 642
 643         for (i = 0; i < end; i++, out++) {
 644                 struct bts_struct ret;
 645                 int retval;
 646
 647                 retval = ds_read_bts(ds, i, &ret);
 648                 if (retval < 0)
 649                         return retval;
 650
 651                 if (copy_to_user(out, &ret, sizeof(ret)))
 652                         return -EFAULT;
 653         }
 654
 655         ds_clear(ds);
 656
 657         return end;
 658 }
 659
 660 static int ptrace_bts_realloc(struct task_struct *child,
 661                               int size, int reduce_size)
 662 {
 663         unsigned long rlim, vm;
 664         int ret, old_size;
 665
 666         if (size < 0)
 667                 return -EINVAL;
 668
 669         old_size = ds_get_bts_size((void *)child->thread.ds_area_msr);
 670         if (old_size < 0)
 671                 return old_size;
 672
 673         ret = ds_free((void **)&child->thread.ds_area_msr);
 674         if (ret < 0)
 675                 goto out;
 676
 677         size >>= PAGE_SHIFT;
 678         old_size >>= PAGE_SHIFT;
 679
 680         current->mm->total_vm  -= old_size;
 681         current->mm->locked_vm -= old_size;
 682
 683         if (size == 0)
 684                 goto out;
 685
 686         rlim = current->signal->rlim[RLIMIT_AS].rlim_cur >> PAGE_SHIFT;
 687         vm = current->mm->total_vm  + size;
 688         if (rlim < vm) {
 689                 ret = -ENOMEM;
 690
 691                 if (!reduce_size)
 692                         goto out;
 693
 694                 size = rlim - current->mm->total_vm;
 695                 if (size <= 0)
 696                         goto out;
 697         }
 698
 699         rlim = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur >> PAGE_SHIFT;
 700         vm = current->mm->locked_vm  + size;
 701         if (rlim < vm) {
 702                 ret = -ENOMEM;
 703
 704                 if (!reduce_size)
 705                         goto out;
 706
 707                 size = rlim - current->mm->locked_vm;
 708                 if (size <= 0)
 709                         goto out;
 710         }
 711
 712         ret = ds_allocate((void **)&child->thread.ds_area_msr,
 713                           size << PAGE_SHIFT);
 714         if (ret < 0)
 715                 goto out;
 716
 717         current->mm->total_vm  += size;
 718         current->mm->locked_vm += size;
 719
 720 out:
 721         if (child->thread.ds_area_msr)
 722                 set_tsk_thread_flag(child, TIF_DS_AREA_MSR);
 723         else
 724                 clear_tsk_thread_flag(child, TIF_DS_AREA_MSR);
 725
 726         return ret;
 727 }
 728
 729 static int ptrace_bts_config(struct task_struct *child,
 730                              long cfg_size,
 731                              const struct ptrace_bts_config __user *ucfg)
 732 {
 733         struct ptrace_bts_config cfg;
 734         int bts_size, ret = 0;
 735         void *ds;
 736
 737         if (cfg_size < sizeof(cfg))
 738                 return -EIO;
 739
 740         if (copy_from_user(&cfg, ucfg, sizeof(cfg)))
 741                 return -EFAULT;
 742
 743         if ((int)cfg.size < 0)
 744                 return -EINVAL;
 745
 746         bts_size = 0;
 747         ds = (void *)child->thread.ds_area_msr;
 748         if (ds) {
 749                 bts_size = ds_get_bts_size(ds);
 750                 if (bts_size < 0)
 751                         return bts_size;
 752         }
 753         cfg.size = PAGE_ALIGN(cfg.size);
 754
 755         if (bts_size != cfg.size) {
 756                 ret = ptrace_bts_realloc(child, cfg.size,
 757                                          cfg.flags & PTRACE_BTS_O_CUT_SIZE);
 758                 if (ret < 0)
 759                         goto errout;
 760
 761                 ds = (void *)child->thread.ds_area_msr;
 762         }
 763
 764         if (cfg.flags & PTRACE_BTS_O_SIGNAL)
 765                 ret = ds_set_overflow(ds, DS_O_SIGNAL);
 766         else
 767                 ret = ds_set_overflow(ds, DS_O_WRAP);
 768         if (ret < 0)
 769                 goto errout;
 770
 771         if (cfg.flags & PTRACE_BTS_O_TRACE)
 772                 child->thread.debugctlmsr |= ds_debugctl_mask();
 773         else
 774                 child->thread.debugctlmsr &= ~ds_debugctl_mask();
 775
 776         if (cfg.flags & PTRACE_BTS_O_SCHED)
 777                 set_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 778         else
 779                 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 780
 781         ret = sizeof(cfg);
 782
 783 out:
 784         if (child->thread.debugctlmsr)
 785                 set_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 786         else
 787                 clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 788
 789         return ret;
 790
 791 errout:
 792         child->thread.debugctlmsr &= ~ds_debugctl_mask();
 793         clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 794         goto out;
 795 }
 796
 797 static int ptrace_bts_status(struct task_struct *child,
 798                              long cfg_size,
 799                              struct ptrace_bts_config __user *ucfg)
 800 {
 801         void *ds = (void *)child->thread.ds_area_msr;
 802         struct ptrace_bts_config cfg;
 803
 804         if (cfg_size < sizeof(cfg))
 805                 return -EIO;
 806
 807         memset(&cfg, 0, sizeof(cfg));
 808
 809         if (ds) {
 810                 cfg.size = ds_get_bts_size(ds);
 811
 812                 if (ds_get_overflow(ds) == DS_O_SIGNAL)
 813                         cfg.flags |= PTRACE_BTS_O_SIGNAL;
 814
 815                 if (test_tsk_thread_flag(child, TIF_DEBUGCTLMSR) &&
 816                     child->thread.debugctlmsr & ds_debugctl_mask())
 817                         cfg.flags |= PTRACE_BTS_O_TRACE;
 818
 819                 if (test_tsk_thread_flag(child, TIF_BTS_TRACE_TS))
 820                         cfg.flags |= PTRACE_BTS_O_SCHED;
 821         }
 822
 823         cfg.bts_size = sizeof(struct bts_struct);
 824
 825         if (copy_to_user(ucfg, &cfg, sizeof(cfg)))
 826                 return -EFAULT;
 827
 828         return sizeof(cfg);
 829 }
 830
 831 void ptrace_bts_take_timestamp(struct task_struct *tsk,
 832                                enum bts_qualifier qualifier)
 833 {
 834         struct bts_struct rec = {
 835                 .qualifier = qualifier,
 836                 .variant.jiffies = jiffies_64
 837         };
 838
 839         ptrace_bts_write_record(tsk, &rec);
 840 }
 841 #endif /* X86_BTS */
 842
 843 /*
 844  * Called by kernel/ptrace.c when detaching..
 845  *
 846  * Make sure the single step bit is not set.
 847  */
 848 void ptrace_disable(struct task_struct *child)
 849 {
 850         user_disable_single_step(child);
 851 #ifdef TIF_SYSCALL_EMU
 852         clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
 853 #endif
 854         if (child->thread.ds_area_msr) {
 855 #ifdef X86_BTS
 856                 ptrace_bts_realloc(child, 0, 0);
 857 #endif
 858                 child->thread.debugctlmsr &= ~ds_debugctl_mask();
 859                 if (!child->thread.debugctlmsr)
 860                         clear_tsk_thread_flag(child, TIF_DEBUGCTLMSR);
 861                 clear_tsk_thread_flag(child, TIF_BTS_TRACE_TS);
 862         }
 863 }
 864
 865 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 866 static const struct user_regset_view user_x86_32_view; /* Initialized below. */
 867 #endif
 868
 869 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 870 {
 871         int ret;
 872         unsigned long __user *datap = (unsigned long __user *)data;
 873
 874         switch (request) {
 875         /* read the word at location addr in the USER area. */
 876         case PTRACE_PEEKUSR: {
 877                 unsigned long tmp;
 878
 879                 ret = -EIO;
 880                 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
 881                     addr >= sizeof(struct user))
 882                         break;
 883
 884                 tmp = 0;  /* Default return condition */
 885                 if (addr < sizeof(struct user_regs_struct))
 886                         tmp = getreg(child, addr);
 887                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 888                          addr <= offsetof(struct user, u_debugreg[7])) {
 889                         addr -= offsetof(struct user, u_debugreg[0]);
 890                         tmp = ptrace_get_debugreg(child, addr / sizeof(data));
 891                 }
 892                 ret = put_user(tmp, datap);
 893                 break;
 894         }
 895
 896         case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 897                 ret = -EIO;
 898                 if ((addr & (sizeof(data) - 1)) || addr < 0 ||
 899                     addr >= sizeof(struct user))
 900                         break;
 901
 902                 if (addr < sizeof(struct user_regs_struct))
 903                         ret = putreg(child, addr, data);
 904                 else if (addr >= offsetof(struct user, u_debugreg[0]) &&
 905                          addr <= offsetof(struct user, u_debugreg[7])) {
 906                         addr -= offsetof(struct user, u_debugreg[0]);
 907                         ret = ptrace_set_debugreg(child,
 908                                                   addr / sizeof(data), data);
 909                 }
 910                 break;
 911
 912         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
 913                 return copy_regset_to_user(child,
 914                                            task_user_regset_view(current),
 915                                            REGSET_GENERAL,
 916                                            0, sizeof(struct user_regs_struct),
 917                                            datap);
 918
 919         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
 920                 return copy_regset_from_user(child,
 921                                              task_user_regset_view(current),
 922                                              REGSET_GENERAL,
 923                                              0, sizeof(struct user_regs_struct),
 924                                              datap);
 925
 926         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
 927                 return copy_regset_to_user(child,
 928                                            task_user_regset_view(current),
 929                                            REGSET_FP,
 930                                            0, sizeof(struct user_i387_struct),
 931                                            datap);
 932
 933         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
 934                 return copy_regset_from_user(child,
 935                                              task_user_regset_view(current),
 936                                              REGSET_FP,
 937                                              0, sizeof(struct user_i387_struct),
 938                                              datap);
 939
 940 #ifdef CONFIG_X86_32
 941         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
 942                 return copy_regset_to_user(child, &user_x86_32_view,
 943                                            REGSET_XFP,
 944                                            0, sizeof(struct user_fxsr_struct),
 945                                            datap);
 946
 947         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
 948                 return copy_regset_from_user(child, &user_x86_32_view,
 949                                              REGSET_XFP,
 950                                              0, sizeof(struct user_fxsr_struct),
 951                                              datap);
 952 #endif
 953
 954 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
 955         case PTRACE_GET_THREAD_AREA:
 956                 if (addr < 0)
 957                         return -EIO;
 958                 ret = do_get_thread_area(child, addr,
 959                                          (struct user_desc __user *) data);
 960                 break;
 961
 962         case PTRACE_SET_THREAD_AREA:
 963                 if (addr < 0)
 964                         return -EIO;
 965                 ret = do_set_thread_area(child, addr,
 966                                          (struct user_desc __user *) data, 0);
 967                 break;
 968 #endif
 969
 970 #ifdef CONFIG_X86_64
 971                 /* normal 64bit interface to access TLS data.
 972                    Works just like arch_prctl, except that the arguments
 973                    are reversed. */
 974         case PTRACE_ARCH_PRCTL:
 975                 ret = do_arch_prctl(child, data, addr);
 976                 break;
 977 #endif
 978
 979         /*
 980          * These bits need more cooking - not enabled yet:
 981          */
 982 #ifdef X86_BTS
 983         case PTRACE_BTS_CONFIG:
 984                 ret = ptrace_bts_config
 985                         (child, data, (struct ptrace_bts_config __user *)addr);
 986                 break;
 987
 988         case PTRACE_BTS_STATUS:
 989                 ret = ptrace_bts_status
 990                         (child, data, (struct ptrace_bts_config __user *)addr);
 991                 break;
 992
 993         case PTRACE_BTS_SIZE:
 994                 ret = ptrace_bts_get_size(child);
 995                 break;
 996
 997         case PTRACE_BTS_GET:
 998                 ret = ptrace_bts_read_record
 999                         (child, data, (struct bts_struct __user *) addr);
1000                 break;
1001
1002         case PTRACE_BTS_CLEAR:
1003                 ret = ptrace_bts_clear(child);
1004                 break;
1005
1006         case PTRACE_BTS_DRAIN:
1007                 ret = ptrace_bts_drain
1008                         (child, data, (struct bts_struct __user *) addr);
1009                 break;
1010 #endif
1011
1012         default:
1013                 ret = ptrace_request(child, request, addr, data);
1014                 break;
1015         }
1016
1017         return ret;
1018 }
1019
1020 #ifdef CONFIG_IA32_EMULATION
1021
1022 #include <linux/compat.h>
1023 #include <linux/syscalls.h>
1024 #include <asm/ia32.h>
1025 #include <asm/user32.h>
1026
1027 #define R32(l,q)                                                        \
1028         case offsetof(struct user32, regs.l):                           \
1029                 regs->q = value; break
1030
1031 #define SEG32(rs)                                                       \
1032         case offsetof(struct user32, regs.rs):                          \
1033                 return set_segment_reg(child,                           \
1034                                        offsetof(struct user_regs_struct, rs), \
1035                                        value);                          \
1036                 break
1037
1038 static int putreg32(struct task_struct *child, unsigned regno, u32 value)
1039 {
1040         struct pt_regs *regs = task_pt_regs(child);
1041
1042         switch (regno) {
1043
1044         SEG32(cs);
1045         SEG32(ds);
1046         SEG32(es);
1047         SEG32(fs);
1048         SEG32(gs);
1049         SEG32(ss);
1050
1051         R32(ebx, bx);
1052         R32(ecx, cx);
1053         R32(edx, dx);
1054         R32(edi, di);
1055         R32(esi, si);
1056         R32(ebp, bp);
1057         R32(eax, ax);
1058         R32(eip, ip);
1059         R32(esp, sp);
1060
1061         case offsetof(struct user32, regs.orig_eax):
1062                 /*
1063                  * Sign-extend the value so that orig_eax = -1
1064                  * causes (long)orig_ax < 0 tests to fire correctly.
1065                  */
1066                 regs->orig_ax = (long) (s32) value;
1067                 break;
1068
1069         case offsetof(struct user32, regs.eflags):
1070                 return set_flags(child, value);
1071
1072         case offsetof(struct user32, u_debugreg[0]) ...
1073                 offsetof(struct user32, u_debugreg[7]):
1074                 regno -= offsetof(struct user32, u_debugreg[0]);
1075                 return ptrace_set_debugreg(child, regno / 4, value);
1076
1077         default:
1078                 if (regno > sizeof(struct user32) || (regno & 3))
1079                         return -EIO;
1080
1081                 /*
1082                  * Other dummy fields in the virtual user structure
1083                  * are ignored
1084                  */
1085                 break;
1086         }
1087         return 0;
1088 }
1089
1090 #undef R32
1091 #undef SEG32
1092
1093 #define R32(l,q)                                                        \
1094         case offsetof(struct user32, regs.l):                           \
1095                 *val = regs->q; break
1096
1097 #define SEG32(rs)                                                       \
1098         case offsetof(struct user32, regs.rs):                          \
1099                 *val = get_segment_reg(child,                           \
1100                                        offsetof(struct user_regs_struct, rs)); \
1101                 break
1102
1103 static int getreg32(struct task_struct *child, unsigned regno, u32 *val)
1104 {
1105         struct pt_regs *regs = task_pt_regs(child);
1106
1107         switch (regno) {
1108
1109         SEG32(ds);
1110         SEG32(es);
1111         SEG32(fs);
1112         SEG32(gs);
1113
1114         R32(cs, cs);
1115         R32(ss, ss);
1116         R32(ebx, bx);
1117         R32(ecx, cx);
1118         R32(edx, dx);
1119         R32(edi, di);
1120         R32(esi, si);
1121         R32(ebp, bp);
1122         R32(eax, ax);
1123         R32(orig_eax, orig_ax);
1124         R32(eip, ip);
1125         R32(esp, sp);
1126
1127         case offsetof(struct user32, regs.eflags):
1128                 *val = get_flags(child);
1129                 break;
1130
1131         case offsetof(struct user32, u_debugreg[0]) ...
1132                 offsetof(struct user32, u_debugreg[7]):
1133                 regno -= offsetof(struct user32, u_debugreg[0]);
1134                 *val = ptrace_get_debugreg(child, regno / 4);
1135                 break;
1136
1137         default:
1138                 if (regno > sizeof(struct user32) || (regno & 3))
1139                         return -EIO;
1140
1141                 /*
1142                  * Other dummy fields in the virtual user structure
1143                  * are ignored
1144                  */
1145                 *val = 0;
1146                 break;
1147         }
1148         return 0;
1149 }
1150
1151 #undef R32
1152 #undef SEG32
1153
1154 static int genregs32_get(struct task_struct *target,
1155                          const struct user_regset *regset,
1156                          unsigned int pos, unsigned int count,
1157                          void *kbuf, void __user *ubuf)
1158 {
1159         if (kbuf) {
1160                 compat_ulong_t *k = kbuf;
1161                 while (count > 0) {
1162                         getreg32(target, pos, k++);
1163                         count -= sizeof(*k);
1164                         pos += sizeof(*k);
1165                 }
1166         } else {
1167                 compat_ulong_t __user *u = ubuf;
1168                 while (count > 0) {
1169                         compat_ulong_t word;
1170                         getreg32(target, pos, &word);
1171                         if (__put_user(word, u++))
1172                                 return -EFAULT;
1173                         count -= sizeof(*u);
1174                         pos += sizeof(*u);
1175                 }
1176         }
1177
1178         return 0;
1179 }
1180
1181 static int genregs32_set(struct task_struct *target,
1182                          const struct user_regset *regset,
1183                          unsigned int pos, unsigned int count,
1184                          const void *kbuf, const void __user *ubuf)
1185 {
1186         int ret = 0;
1187         if (kbuf) {
1188                 const compat_ulong_t *k = kbuf;
1189                 while (count > 0 && !ret) {
1190                         ret = putreg32(target, pos, *k++);
1191                         count -= sizeof(*k);
1192                         pos += sizeof(*k);
1193                 }
1194         } else {
1195                 const compat_ulong_t __user *u = ubuf;
1196                 while (count > 0 && !ret) {
1197                         compat_ulong_t word;
1198                         ret = __get_user(word, u++);
1199                         if (ret)
1200                                 break;
1201                         ret = putreg32(target, pos, word);
1202                         count -= sizeof(*u);
1203                         pos += sizeof(*u);
1204                 }
1205         }
1206         return ret;
1207 }
1208
1209 static long ptrace32_siginfo(unsigned request, u32 pid, u32 addr, u32 data)
1210 {
1211         siginfo_t __user *si = compat_alloc_user_space(sizeof(siginfo_t));
1212         compat_siginfo_t __user *si32 = compat_ptr(data);
1213         siginfo_t ssi;
1214         int ret;
1215
1216         if (request == PTRACE_SETSIGINFO) {
1217                 memset(&ssi, 0, sizeof(siginfo_t));
1218                 ret = copy_siginfo_from_user32(&ssi, si32);
1219                 if (ret)
1220                         return ret;
1221                 if (copy_to_user(si, &ssi, sizeof(siginfo_t)))
1222                         return -EFAULT;
1223         }
1224         ret = sys_ptrace(request, pid, addr, (unsigned long)si);
1225         if (ret)
1226                 return ret;
1227         if (request == PTRACE_GETSIGINFO) {
1228                 if (copy_from_user(&ssi, si, sizeof(siginfo_t)))
1229                         return -EFAULT;
1230                 ret = copy_siginfo_to_user32(si32, &ssi);
1231         }
1232         return ret;
1233 }
1234
1235 asmlinkage long sys32_ptrace(long request, u32 pid, u32 addr, u32 data)
1236 {
1237         struct task_struct *child;
1238         struct pt_regs *childregs;
1239         void __user *datap = compat_ptr(data);
1240         int ret;
1241         __u32 val;
1242
1243         switch (request) {
1244         case PTRACE_TRACEME:
1245         case PTRACE_ATTACH:
1246         case PTRACE_KILL:
1247         case PTRACE_CONT:
1248         case PTRACE_SINGLESTEP:
1249         case PTRACE_SINGLEBLOCK:
1250         case PTRACE_DETACH:
1251         case PTRACE_SYSCALL:
1252         case PTRACE_OLDSETOPTIONS:
1253         case PTRACE_SETOPTIONS:
1254         case PTRACE_SET_THREAD_AREA:
1255         case PTRACE_GET_THREAD_AREA:
1256 #ifdef X86_BTS
1257         case PTRACE_BTS_CONFIG:
1258         case PTRACE_BTS_STATUS:
1259         case PTRACE_BTS_SIZE:
1260         case PTRACE_BTS_GET:
1261         case PTRACE_BTS_CLEAR:
1262         case PTRACE_BTS_DRAIN:
1263 #endif
1264                 return sys_ptrace(request, pid, addr, data);
1265
1266         default:
1267                 return -EINVAL;
1268
1269         case PTRACE_PEEKTEXT:
1270         case PTRACE_PEEKDATA:
1271         case PTRACE_POKEDATA:
1272         case PTRACE_POKETEXT:
1273         case PTRACE_POKEUSR:
1274         case PTRACE_PEEKUSR:
1275         case PTRACE_GETREGS:
1276         case PTRACE_SETREGS:
1277         case PTRACE_SETFPREGS:
1278         case PTRACE_GETFPREGS:
1279         case PTRACE_SETFPXREGS:
1280         case PTRACE_GETFPXREGS:
1281         case PTRACE_GETEVENTMSG:
1282                 break;
1283
1284         case PTRACE_SETSIGINFO:
1285         case PTRACE_GETSIGINFO:
1286                 return ptrace32_siginfo(request, pid, addr, data);
1287         }
1288
1289         child = ptrace_get_task_struct(pid);
1290         if (IS_ERR(child))
1291                 return PTR_ERR(child);
1292
1293         ret = ptrace_check_attach(child, request == PTRACE_KILL);
1294         if (ret < 0)
1295                 goto out;
1296
1297         childregs = task_pt_regs(child);
1298
1299         switch (request) {
1300         case PTRACE_PEEKUSR:
1301                 ret = getreg32(child, addr, &val);
1302                 if (ret == 0)
1303                         ret = put_user(val, (__u32 __user *)datap);
1304                 break;
1305
1306         case PTRACE_POKEUSR:
1307                 ret = putreg32(child, addr, data);
1308                 break;
1309
1310         case PTRACE_GETREGS:    /* Get all gp regs from the child. */
1311                 return copy_regset_to_user(child, &user_x86_32_view,
1312                                            REGSET_GENERAL,
1313                                            0, sizeof(struct user_regs_struct32),
1314                                            datap);
1315
1316         case PTRACE_SETREGS:    /* Set all gp regs in the child. */
1317                 return copy_regset_from_user(child, &user_x86_32_view,
1318                                              REGSET_GENERAL, 0,
1319                                              sizeof(struct user_regs_struct32),
1320                                              datap);
1321
1322         case PTRACE_GETFPREGS:  /* Get the child FPU state. */
1323                 return copy_regset_to_user(child, &user_x86_32_view,
1324                                            REGSET_FP, 0,
1325                                            sizeof(struct user_i387_ia32_struct),
1326                                            datap);
1327
1328         case PTRACE_SETFPREGS:  /* Set the child FPU state. */
1329                 return copy_regset_from_user(
1330                         child, &user_x86_32_view, REGSET_FP,
1331                         0, sizeof(struct user_i387_ia32_struct), datap);
1332
1333         case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
1334                 return copy_regset_to_user(child, &user_x86_32_view,
1335                                            REGSET_XFP, 0,
1336                                            sizeof(struct user32_fxsr_struct),
1337                                            datap);
1338
1339         case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
1340                 return copy_regset_from_user(child, &user_x86_32_view,
1341                                              REGSET_XFP, 0,
1342                                              sizeof(struct user32_fxsr_struct),
1343                                              datap);
1344
1345         default:
1346                 return compat_ptrace_request(child, request, addr, data);
1347         }
1348
1349  out:
1350         put_task_struct(child);
1351         return ret;
1352 }
1353
1354 #endif  /* CONFIG_IA32_EMULATION */
1355
1356 #ifdef CONFIG_X86_64
1357
1358 static const struct user_regset x86_64_regsets[] = {
1359         [REGSET_GENERAL] = {
1360                 .core_note_type = NT_PRSTATUS,
1361                 .n = sizeof(struct user_regs_struct) / sizeof(long),
1362                 .size = sizeof(long), .align = sizeof(long),
1363                 .get = genregs_get, .set = genregs_set
1364         },
1365         [REGSET_FP] = {
1366                 .core_note_type = NT_PRFPREG,
1367                 .n = sizeof(struct user_i387_struct) / sizeof(long),
1368                 .size = sizeof(long), .align = sizeof(long),
1369                 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1370         },
1371 };
1372
1373 static const struct user_regset_view user_x86_64_view = {
1374         .name = "x86_64", .e_machine = EM_X86_64,
1375         .regsets = x86_64_regsets, .n = ARRAY_SIZE(x86_64_regsets)
1376 };
1377
1378 #else  /* CONFIG_X86_32 */
1379
1380 #define user_regs_struct32      user_regs_struct
1381 #define genregs32_get           genregs_get
1382 #define genregs32_set           genregs_set
1383
1384 #endif  /* CONFIG_X86_64 */
1385
1386 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1387 static const struct user_regset x86_32_regsets[] = {
1388         [REGSET_GENERAL] = {
1389                 .core_note_type = NT_PRSTATUS,
1390                 .n = sizeof(struct user_regs_struct32) / sizeof(u32),
1391                 .size = sizeof(u32), .align = sizeof(u32),
1392                 .get = genregs32_get, .set = genregs32_set
1393         },
1394         [REGSET_FP] = {
1395                 .core_note_type = NT_PRFPREG,
1396                 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1397                 .size = sizeof(u32), .align = sizeof(u32),
1398                 .active = fpregs_active, .get = fpregs_get, .set = fpregs_set
1399         },
1400         [REGSET_XFP] = {
1401                 .core_note_type = NT_PRXFPREG,
1402                 .n = sizeof(struct user_i387_struct) / sizeof(u32),
1403                 .size = sizeof(u32), .align = sizeof(u32),
1404                 .active = xfpregs_active, .get = xfpregs_get, .set = xfpregs_set
1405         },
1406         [REGSET_TLS] = {
1407                 .core_note_type = NT_386_TLS,
1408                 .n = GDT_ENTRY_TLS_ENTRIES, .bias = GDT_ENTRY_TLS_MIN,
1409                 .size = sizeof(struct user_desc),
1410                 .align = sizeof(struct user_desc),
1411                 .active = regset_tls_active,
1412                 .get = regset_tls_get, .set = regset_tls_set
1413         },
1414 };
1415
1416 static const struct user_regset_view user_x86_32_view = {
1417         .name = "i386", .e_machine = EM_386,
1418         .regsets = x86_32_regsets, .n = ARRAY_SIZE(x86_32_regsets)
1419 };
1420 #endif
1421
1422 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1423 {
1424 #ifdef CONFIG_IA32_EMULATION
1425         if (test_tsk_thread_flag(task, TIF_IA32))
1426 #endif
1427 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
1428                 return &user_x86_32_view;
1429 #endif
1430 #ifdef CONFIG_X86_64
1431         return &user_x86_64_view;
1432 #endif
1433 }
1434
1435 #ifdef CONFIG_X86_32
1436
1437 void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
1438 {
1439         struct siginfo info;
1440
1441         tsk->thread.trap_no = 1;
1442         tsk->thread.error_code = error_code;
1443
1444         memset(&info, 0, sizeof(info));
1445         info.si_signo = SIGTRAP;
1446         info.si_code = TRAP_BRKPT;
1447
1448         /* User-mode ip? */
1449         info.si_addr = user_mode_vm(regs) ? (void __user *) regs->ip : NULL;
1450
1451         /* Send us the fake SIGTRAP */
1452         force_sig_info(SIGTRAP, &info, tsk);
1453 }
1454
1455 /* notification of system call entry/exit
1456  * - triggered by current->work.syscall_trace
1457  */
1458 __attribute__((regparm(3)))
1459 int do_syscall_trace(struct pt_regs *regs, int entryexit)
1460 {
1461         int is_sysemu = test_thread_flag(TIF_SYSCALL_EMU);
1462         /*
1463          * With TIF_SYSCALL_EMU set we want to ignore TIF_SINGLESTEP for syscall
1464          * interception
1465          */
1466         int is_singlestep = !is_sysemu && test_thread_flag(TIF_SINGLESTEP);
1467         int ret = 0;
1468
1469         /* do the secure computing check first */
1470         if (!entryexit)
1471                 secure_computing(regs->orig_ax);
1472
1473         if (unlikely(current->audit_context)) {
1474                 if (entryexit)
1475                         audit_syscall_exit(AUDITSC_RESULT(regs->ax),
1476                                                 regs->ax);
1477                 /* Debug traps, when using PTRACE_SINGLESTEP, must be sent only
1478                  * on the syscall exit path. Normally, when TIF_SYSCALL_AUDIT is
1479                  * not used, entry.S will call us only on syscall exit, not
1480                  * entry; so when TIF_SYSCALL_AUDIT is used we must avoid
1481                  * calling send_sigtrap() on syscall entry.
1482                  *
1483                  * Note that when PTRACE_SYSEMU_SINGLESTEP is used,
1484                  * is_singlestep is false, despite his name, so we will still do
1485                  * the correct thing.
1486                  */
1487                 else if (is_singlestep)
1488                         goto out;
1489         }
1490
1491         if (!(current->ptrace & PT_PTRACED))
1492                 goto out;
1493
1494         /* If a process stops on the 1st tracepoint with SYSCALL_TRACE
1495          * and then is resumed with SYSEMU_SINGLESTEP, it will come in
1496          * here. We have to check this and return */
1497         if (is_sysemu && entryexit)
1498                 return 0;
1499
1500         /* Fake a debug trap */
1501         if (is_singlestep)
1502                 send_sigtrap(current, regs, 0);
1503
1504         if (!test_thread_flag(TIF_SYSCALL_TRACE) && !is_sysemu)
1505                 goto out;
1506
1507         /* the 0x80 provides a way for the tracing parent to distinguish
1508            between a syscall stop and SIGTRAP delivery */
1509         /* Note that the debugger could change the result of test_thread_flag!*/
1510         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ? 0x80:0));
1511
1512         /*
1513          * this isn't the same as continuing with a signal, but it will do
1514          * for normal use.  strace only continues with a signal if the
1515          * stopping signal is not SIGTRAP.  -brl
1516          */
1517         if (current->exit_code) {
1518                 send_sig(current->exit_code, current, 1);
1519                 current->exit_code = 0;
1520         }
1521         ret = is_sysemu;
1522 out:
1523         if (unlikely(current->audit_context) && !entryexit)
1524                 audit_syscall_entry(AUDIT_ARCH_I386, regs->orig_ax,
1525                                     regs->bx, regs->cx, regs->dx, regs->si);
1526         if (ret == 0)
1527                 return 0;
1528
1529         regs->orig_ax = -1; /* force skip of syscall restarting */
1530         if (unlikely(current->audit_context))
1531                 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1532         return 1;
1533 }
1534
1535 #else  /* CONFIG_X86_64 */
1536
1537 static void syscall_trace(struct pt_regs *regs)
1538 {
1539
1540 #if 0
1541         printk("trace %s ip %lx sp %lx ax %d origrax %d caller %lx tiflags %x ptrace %x\n",
1542                current->comm,
1543                regs->ip, regs->sp, regs->ax, regs->orig_ax, __builtin_return_address(0),
1544                current_thread_info()->flags, current->ptrace);
1545 #endif
1546
1547         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
1548                                 ? 0x80 : 0));
1549         /*
1550          * this isn't the same as continuing with a signal, but it will do
1551          * for normal use.  strace only continues with a signal if the
1552          * stopping signal is not SIGTRAP.  -brl
1553          */
1554         if (current->exit_code) {
1555                 send_sig(current->exit_code, current, 1);
1556                 current->exit_code = 0;
1557         }
1558 }
1559
1560 asmlinkage void syscall_trace_enter(struct pt_regs *regs)
1561 {
1562         /* do the secure computing check first */
1563         secure_computing(regs->orig_ax);
1564
1565         if (test_thread_flag(TIF_SYSCALL_TRACE)
1566             && (current->ptrace & PT_PTRACED))
1567                 syscall_trace(regs);
1568
1569         if (unlikely(current->audit_context)) {
1570                 if (test_thread_flag(TIF_IA32)) {
1571                         audit_syscall_entry(AUDIT_ARCH_I386,
1572                                             regs->orig_ax,
1573                                             regs->bx, regs->cx,
1574                                             regs->dx, regs->si);
1575                 } else {
1576                         audit_syscall_entry(AUDIT_ARCH_X86_64,
1577                                             regs->orig_ax,
1578                                             regs->di, regs->si,
1579                                             regs->dx, regs->r10);
1580                 }
1581         }
1582 }
1583
1584 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1585 {
1586         if (unlikely(current->audit_context))
1587                 audit_syscall_exit(AUDITSC_RESULT(regs->ax), regs->ax);
1588
1589         if ((test_thread_flag(TIF_SYSCALL_TRACE)
1590              || test_thread_flag(TIF_SINGLESTEP))
1591             && (current->ptrace & PT_PTRACED))
1592                 syscall_trace(regs);
1593 }
1594
1595 #endif  /* CONFIG_X86_32 */