arch/s390/kernel/ptrace.c

   1 /*
   2  *  arch/s390/kernel/ptrace.c
   3  *
   4  *  S390 version
   5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6  *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com),
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  *
   9  *  Based on PowerPC version
  10  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  11  *
  12  *  Derived from "arch/m68k/kernel/ptrace.c"
  13  *  Copyright (C) 1994 by Hamish Macdonald
  14  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
  15  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  16  *
  17  * Modified by Cort Dougan (cort@cs.nmt.edu)
  18  *
  19  *
  20  * This file is subject to the terms and conditions of the GNU General
  21  * Public License.  See the file README.legal in the main directory of
  22  * this archive for more details.
  23  */
  24
  25 #include <linux/kernel.h>
  26 #include <linux/sched.h>
  27 #include <linux/mm.h>
  28 #include <linux/smp.h>
  29 #include <linux/errno.h>
  30 #include <linux/ptrace.h>
  31 #include <linux/user.h>
  32 #include <linux/security.h>
  33 #include <linux/audit.h>
  34 #include <linux/signal.h>
  35 #include <linux/elf.h>
  36 #include <linux/regset.h>
  37 #include <linux/tracehook.h>
  38 #include <linux/seccomp.h>
  39 #include <trace/syscall.h>
  40 #include <asm/compat.h>
  41 #include <asm/segment.h>
  42 #include <asm/page.h>
  43 #include <asm/pgtable.h>
  44 #include <asm/pgalloc.h>
  45 #include <asm/system.h>
  46 #include <asm/uaccess.h>
  47 #include <asm/unistd.h>
  48 #include "entry.h"
  49
  50 #ifdef CONFIG_COMPAT
  51 #include "compat_ptrace.h"
  52 #endif
  53
  54 #define CREATE_TRACE_POINTS
  55 #include <trace/events/syscalls.h>
  56
  57 enum s390_regset {
  58         REGSET_GENERAL,
  59         REGSET_FP,
  60         REGSET_GENERAL_EXTENDED,
  61 };
  62
  63 static void
  64 FixPerRegisters(struct task_struct *task)
  65 {
  66         struct pt_regs *regs;
  67         per_struct *per_info;
  68
  69         regs = task_pt_regs(task);
  70         per_info = (per_struct *) &task->thread.per_info;
  71         per_info->control_regs.bits.em_instruction_fetch =
  72                 per_info->single_step | per_info->instruction_fetch;
  73
  74         if (per_info->single_step) {
  75                 per_info->control_regs.bits.starting_addr = 0;
  76 #ifdef CONFIG_COMPAT
  77                 if (is_compat_task())
  78                         per_info->control_regs.bits.ending_addr = 0x7fffffffUL;
  79                 else
  80 #endif
  81                         per_info->control_regs.bits.ending_addr = PSW_ADDR_INSN;
  82         } else {
  83                 per_info->control_regs.bits.starting_addr =
  84                         per_info->starting_addr;
  85                 per_info->control_regs.bits.ending_addr =
  86                         per_info->ending_addr;
  87         }
  88         /*
  89          * if any of the control reg tracing bits are on
  90          * we switch on per in the psw
  91          */
  92         if (per_info->control_regs.words.cr[0] & PER_EM_MASK)
  93                 regs->psw.mask |= PSW_MASK_PER;
  94         else
  95                 regs->psw.mask &= ~PSW_MASK_PER;
  96
  97         if (per_info->control_regs.bits.em_storage_alteration)
  98                 per_info->control_regs.bits.storage_alt_space_ctl = 1;
  99         else
 100                 per_info->control_regs.bits.storage_alt_space_ctl = 0;
 101 }
 102
 103 void user_enable_single_step(struct task_struct *task)
 104 {
 105         task->thread.per_info.single_step = 1;
 106         FixPerRegisters(task);
 107 }
 108
 109 void user_disable_single_step(struct task_struct *task)
 110 {
 111         task->thread.per_info.single_step = 0;
 112         FixPerRegisters(task);
 113 }
 114
 115 /*
 116  * Called by kernel/ptrace.c when detaching..
 117  *
 118  * Make sure single step bits etc are not set.
 119  */
 120 void
 121 ptrace_disable(struct task_struct *child)
 122 {
 123         /* make sure the single step bit is not set. */
 124         user_disable_single_step(child);
 125 }
 126
 127 #ifndef CONFIG_64BIT
 128 # define __ADDR_MASK 3
 129 #else
 130 # define __ADDR_MASK 7
 131 #endif
 132
 133 /*
 134  * Read the word at offset addr from the user area of a process. The
 135  * trouble here is that the information is littered over different
 136  * locations. The process registers are found on the kernel stack,
 137  * the floating point stuff and the trace settings are stored in
 138  * the task structure. In addition the different structures in
 139  * struct user contain pad bytes that should be read as zeroes.
 140  * Lovely...
 141  */
 142 static unsigned long __peek_user(struct task_struct *child, addr_t addr)
 143 {
 144         struct user *dummy = NULL;
 145         addr_t offset, tmp;
 146
 147         if (addr < (addr_t) &dummy->regs.acrs) {
 148                 /*
 149                  * psw and gprs are stored on the stack
 150                  */
 151                 tmp = *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr);
 152                 if (addr == (addr_t) &dummy->regs.psw.mask)
 153                         /* Remove per bit from user psw. */
 154                         tmp &= ~PSW_MASK_PER;
 155
 156         } else if (addr < (addr_t) &dummy->regs.orig_gpr2) {
 157                 /*
 158                  * access registers are stored in the thread structure
 159                  */
 160                 offset = addr - (addr_t) &dummy->regs.acrs;
 161 #ifdef CONFIG_64BIT
 162                 /*
 163                  * Very special case: old & broken 64 bit gdb reading
 164                  * from acrs[15]. Result is a 64 bit value. Read the
 165                  * 32 bit acrs[15] value and shift it by 32. Sick...
 166                  */
 167                 if (addr == (addr_t) &dummy->regs.acrs[15])
 168                         tmp = ((unsigned long) child->thread.acrs[15]) << 32;
 169                 else
 170 #endif
 171                 tmp = *(addr_t *)((addr_t) &child->thread.acrs + offset);
 172
 173         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 174                 /*
 175                  * orig_gpr2 is stored on the kernel stack
 176                  */
 177                 tmp = (addr_t) task_pt_regs(child)->orig_gpr2;
 178
 179         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 180                 /*
 181                  * prevent reads of padding hole between
 182                  * orig_gpr2 and fp_regs on s390.
 183                  */
 184                 tmp = 0;
 185
 186         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 187                 /*
 188                  * floating point regs. are stored in the thread structure
 189                  */
 190                 offset = addr - (addr_t) &dummy->regs.fp_regs;
 191                 tmp = *(addr_t *)((addr_t) &child->thread.fp_regs + offset);
 192                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc)
 193                         tmp &= (unsigned long) FPC_VALID_MASK
 194                                 << (BITS_PER_LONG - 32);
 195
 196         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 197                 /*
 198                  * per_info is found in the thread structure
 199                  */
 200                 offset = addr - (addr_t) &dummy->regs.per_info;
 201                 tmp = *(addr_t *)((addr_t) &child->thread.per_info + offset);
 202
 203         } else
 204                 tmp = 0;
 205
 206         return tmp;
 207 }
 208
 209 static int
 210 peek_user(struct task_struct *child, addr_t addr, addr_t data)
 211 {
 212         addr_t tmp, mask;
 213
 214         /*
 215          * Stupid gdb peeks/pokes the access registers in 64 bit with
 216          * an alignment of 4. Programmers from hell...
 217          */
 218         mask = __ADDR_MASK;
 219 #ifdef CONFIG_64BIT
 220         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 221             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 222                 mask = 3;
 223 #endif
 224         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 225                 return -EIO;
 226
 227         tmp = __peek_user(child, addr);
 228         return put_user(tmp, (addr_t __user *) data);
 229 }
 230
 231 /*
 232  * Write a word to the user area of a process at location addr. This
 233  * operation does have an additional problem compared to peek_user.
 234  * Stores to the program status word and on the floating point
 235  * control register needs to get checked for validity.
 236  */
 237 static int __poke_user(struct task_struct *child, addr_t addr, addr_t data)
 238 {
 239         struct user *dummy = NULL;
 240         addr_t offset;
 241
 242         if (addr < (addr_t) &dummy->regs.acrs) {
 243                 /*
 244                  * psw and gprs are stored on the stack
 245                  */
 246                 if (addr == (addr_t) &dummy->regs.psw.mask &&
 247 #ifdef CONFIG_COMPAT
 248                     data != PSW_MASK_MERGE(psw_user32_bits, data) &&
 249 #endif
 250                     data != PSW_MASK_MERGE(psw_user_bits, data))
 251                         /* Invalid psw mask. */
 252                         return -EINVAL;
 253 #ifndef CONFIG_64BIT
 254                 if (addr == (addr_t) &dummy->regs.psw.addr)
 255                         /* I'd like to reject addresses without the
 256                            high order bit but older gdb's rely on it */
 257                         data |= PSW_ADDR_AMODE;
 258 #endif
 259                 *(addr_t *)((addr_t) &task_pt_regs(child)->psw + addr) = data;
 260
 261         } else if (addr < (addr_t) (&dummy->regs.orig_gpr2)) {
 262                 /*
 263                  * access registers are stored in the thread structure
 264                  */
 265                 offset = addr - (addr_t) &dummy->regs.acrs;
 266 #ifdef CONFIG_64BIT
 267                 /*
 268                  * Very special case: old & broken 64 bit gdb writing
 269                  * to acrs[15] with a 64 bit value. Ignore the lower
 270                  * half of the value and write the upper 32 bit to
 271                  * acrs[15]. Sick...
 272                  */
 273                 if (addr == (addr_t) &dummy->regs.acrs[15])
 274                         child->thread.acrs[15] = (unsigned int) (data >> 32);
 275                 else
 276 #endif
 277                 *(addr_t *)((addr_t) &child->thread.acrs + offset) = data;
 278
 279         } else if (addr == (addr_t) &dummy->regs.orig_gpr2) {
 280                 /*
 281                  * orig_gpr2 is stored on the kernel stack
 282                  */
 283                 task_pt_regs(child)->orig_gpr2 = data;
 284
 285         } else if (addr < (addr_t) &dummy->regs.fp_regs) {
 286                 /*
 287                  * prevent writes of padding hole between
 288                  * orig_gpr2 and fp_regs on s390.
 289                  */
 290                 return 0;
 291
 292         } else if (addr < (addr_t) (&dummy->regs.fp_regs + 1)) {
 293                 /*
 294                  * floating point regs. are stored in the thread structure
 295                  */
 296                 if (addr == (addr_t) &dummy->regs.fp_regs.fpc &&
 297                     (data & ~((unsigned long) FPC_VALID_MASK
 298                               << (BITS_PER_LONG - 32))) != 0)
 299                         return -EINVAL;
 300                 offset = addr - (addr_t) &dummy->regs.fp_regs;
 301                 *(addr_t *)((addr_t) &child->thread.fp_regs + offset) = data;
 302
 303         } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) {
 304                 /*
 305                  * per_info is found in the thread structure
 306                  */
 307                 offset = addr - (addr_t) &dummy->regs.per_info;
 308                 *(addr_t *)((addr_t) &child->thread.per_info + offset) = data;
 309
 310         }
 311
 312         FixPerRegisters(child);
 313         return 0;
 314 }
 315
 316 static int
 317 poke_user(struct task_struct *child, addr_t addr, addr_t data)
 318 {
 319         addr_t mask;
 320
 321         /*
 322          * Stupid gdb peeks/pokes the access registers in 64 bit with
 323          * an alignment of 4. Programmers from hell indeed...
 324          */
 325         mask = __ADDR_MASK;
 326 #ifdef CONFIG_64BIT
 327         if (addr >= (addr_t) &((struct user *) NULL)->regs.acrs &&
 328             addr < (addr_t) &((struct user *) NULL)->regs.orig_gpr2)
 329                 mask = 3;
 330 #endif
 331         if ((addr & mask) || addr > sizeof(struct user) - __ADDR_MASK)
 332                 return -EIO;
 333
 334         return __poke_user(child, addr, data);
 335 }
 336
 337 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
 338 {
 339         ptrace_area parea;
 340         int copied, ret;
 341
 342         switch (request) {
 343         case PTRACE_PEEKUSR:
 344                 /* read the word at location addr in the USER area. */
 345                 return peek_user(child, addr, data);
 346
 347         case PTRACE_POKEUSR:
 348                 /* write the word at location addr in the USER area */
 349                 return poke_user(child, addr, data);
 350
 351         case PTRACE_PEEKUSR_AREA:
 352         case PTRACE_POKEUSR_AREA:
 353                 if (copy_from_user(&parea, (void __force __user *) addr,
 354                                                         sizeof(parea)))
 355                         return -EFAULT;
 356                 addr = parea.kernel_addr;
 357                 data = parea.process_addr;
 358                 copied = 0;
 359                 while (copied < parea.len) {
 360                         if (request == PTRACE_PEEKUSR_AREA)
 361                                 ret = peek_user(child, addr, data);
 362                         else {
 363                                 addr_t utmp;
 364                                 if (get_user(utmp,
 365                                              (addr_t __force __user *) data))
 366                                         return -EFAULT;
 367                                 ret = poke_user(child, addr, utmp);
 368                         }
 369                         if (ret)
 370                                 return ret;
 371                         addr += sizeof(unsigned long);
 372                         data += sizeof(unsigned long);
 373                         copied += sizeof(unsigned long);
 374                 }
 375                 return 0;
 376         default:
 377                 /* Removing high order bit from addr (only for 31 bit). */
 378                 addr &= PSW_ADDR_INSN;
 379                 return ptrace_request(child, request, addr, data);
 380         }
 381 }
 382
 383 #ifdef CONFIG_COMPAT
 384 /*
 385  * Now the fun part starts... a 31 bit program running in the
 386  * 31 bit emulation tracing another program. PTRACE_PEEKTEXT,
 387  * PTRACE_PEEKDATA, PTRACE_POKETEXT and PTRACE_POKEDATA are easy
 388  * to handle, the difference to the 64 bit versions of the requests
 389  * is that the access is done in multiples of 4 byte instead of
 390  * 8 bytes (sizeof(unsigned long) on 31/64 bit).
 391  * The ugly part are PTRACE_PEEKUSR, PTRACE_PEEKUSR_AREA,
 392  * PTRACE_POKEUSR and PTRACE_POKEUSR_AREA. If the traced program
 393  * is a 31 bit program too, the content of struct user can be
 394  * emulated. A 31 bit program peeking into the struct user of
 395  * a 64 bit program is a no-no.
 396  */
 397
 398 /*
 399  * Same as peek_user but for a 31 bit program.
 400  */
 401 static u32 __peek_user_compat(struct task_struct *child, addr_t addr)
 402 {
 403         struct user32 *dummy32 = NULL;
 404         per_struct32 *dummy_per32 = NULL;
 405         addr_t offset;
 406         __u32 tmp;
 407
 408         if (addr < (addr_t) &dummy32->regs.acrs) {
 409                 /*
 410                  * psw and gprs are stored on the stack
 411                  */
 412                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 413                         /* Fake a 31 bit psw mask. */
 414                         tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
 415                         tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
 416                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 417                         /* Fake a 31 bit psw address. */
 418                         tmp = (__u32) task_pt_regs(child)->psw.addr |
 419                                 PSW32_ADDR_AMODE31;
 420                 } else {
 421                         /* gpr 0-15 */
 422                         tmp = *(__u32 *)((addr_t) &task_pt_regs(child)->psw +
 423                                          addr*2 + 4);
 424                 }
 425         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 426                 /*
 427                  * access registers are stored in the thread structure
 428                  */
 429                 offset = addr - (addr_t) &dummy32->regs.acrs;
 430                 tmp = *(__u32*)((addr_t) &child->thread.acrs + offset);
 431
 432         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 433                 /*
 434                  * orig_gpr2 is stored on the kernel stack
 435                  */
 436                 tmp = *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4);
 437
 438         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 439                 /*
 440                  * prevent reads of padding hole between
 441                  * orig_gpr2 and fp_regs on s390.
 442                  */
 443                 tmp = 0;
 444
 445         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 446                 /*
 447                  * floating point regs. are stored in the thread structure
 448                  */
 449                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
 450                 tmp = *(__u32 *)((addr_t) &child->thread.fp_regs + offset);
 451
 452         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 453                 /*
 454                  * per_info is found in the thread structure
 455                  */
 456                 offset = addr - (addr_t) &dummy32->regs.per_info;
 457                 /* This is magic. See per_struct and per_struct32. */
 458                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
 459                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
 460                     (offset >= (addr_t) &dummy_per32->starting_addr &&
 461                      offset <= (addr_t) &dummy_per32->ending_addr) ||
 462                     offset == (addr_t) &dummy_per32->lowcore.words.address)
 463                         offset = offset*2 + 4;
 464                 else
 465                         offset = offset*2;
 466                 tmp = *(__u32 *)((addr_t) &child->thread.per_info + offset);
 467
 468         } else
 469                 tmp = 0;
 470
 471         return tmp;
 472 }
 473
 474 static int peek_user_compat(struct task_struct *child,
 475                             addr_t addr, addr_t data)
 476 {
 477         __u32 tmp;
 478
 479         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user) - 3)
 480                 return -EIO;
 481
 482         tmp = __peek_user_compat(child, addr);
 483         return put_user(tmp, (__u32 __user *) data);
 484 }
 485
 486 /*
 487  * Same as poke_user but for a 31 bit program.
 488  */
 489 static int __poke_user_compat(struct task_struct *child,
 490                               addr_t addr, addr_t data)
 491 {
 492         struct user32 *dummy32 = NULL;
 493         per_struct32 *dummy_per32 = NULL;
 494         __u32 tmp = (__u32) data;
 495         addr_t offset;
 496
 497         if (addr < (addr_t) &dummy32->regs.acrs) {
 498                 /*
 499                  * psw, gprs, acrs and orig_gpr2 are stored on the stack
 500                  */
 501                 if (addr == (addr_t) &dummy32->regs.psw.mask) {
 502                         /* Build a 64 bit psw mask from 31 bit mask. */
 503                         if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
 504                                 /* Invalid psw mask. */
 505                                 return -EINVAL;
 506                         task_pt_regs(child)->psw.mask =
 507                                 PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
 508                 } else if (addr == (addr_t) &dummy32->regs.psw.addr) {
 509                         /* Build a 64 bit psw address from 31 bit address. */
 510                         task_pt_regs(child)->psw.addr =
 511                                 (__u64) tmp & PSW32_ADDR_INSN;
 512                 } else {
 513                         /* gpr 0-15 */
 514                         *(__u32*)((addr_t) &task_pt_regs(child)->psw
 515                                   + addr*2 + 4) = tmp;
 516                 }
 517         } else if (addr < (addr_t) (&dummy32->regs.orig_gpr2)) {
 518                 /*
 519                  * access registers are stored in the thread structure
 520                  */
 521                 offset = addr - (addr_t) &dummy32->regs.acrs;
 522                 *(__u32*)((addr_t) &child->thread.acrs + offset) = tmp;
 523
 524         } else if (addr == (addr_t) (&dummy32->regs.orig_gpr2)) {
 525                 /*
 526                  * orig_gpr2 is stored on the kernel stack
 527                  */
 528                 *(__u32*)((addr_t) &task_pt_regs(child)->orig_gpr2 + 4) = tmp;
 529
 530         } else if (addr < (addr_t) &dummy32->regs.fp_regs) {
 531                 /*
 532                  * prevent writess of padding hole between
 533                  * orig_gpr2 and fp_regs on s390.
 534                  */
 535                 return 0;
 536
 537         } else if (addr < (addr_t) (&dummy32->regs.fp_regs + 1)) {
 538                 /*
 539                  * floating point regs. are stored in the thread structure
 540                  */
 541                 if (addr == (addr_t) &dummy32->regs.fp_regs.fpc &&
 542                     (tmp & ~FPC_VALID_MASK) != 0)
 543                         /* Invalid floating point control. */
 544                         return -EINVAL;
 545                 offset = addr - (addr_t) &dummy32->regs.fp_regs;
 546                 *(__u32 *)((addr_t) &child->thread.fp_regs + offset) = tmp;
 547
 548         } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) {
 549                 /*
 550                  * per_info is found in the thread structure.
 551                  */
 552                 offset = addr - (addr_t) &dummy32->regs.per_info;
 553                 /*
 554                  * This is magic. See per_struct and per_struct32.
 555                  * By incident the offsets in per_struct are exactly
 556                  * twice the offsets in per_struct32 for all fields.
 557                  * The 8 byte fields need special handling though,
 558                  * because the second half (bytes 4-7) is needed and
 559                  * not the first half.
 560                  */
 561                 if ((offset >= (addr_t) &dummy_per32->control_regs &&
 562                      offset < (addr_t) (&dummy_per32->control_regs + 1)) ||
 563                     (offset >= (addr_t) &dummy_per32->starting_addr &&
 564                      offset <= (addr_t) &dummy_per32->ending_addr) ||
 565                     offset == (addr_t) &dummy_per32->lowcore.words.address)
 566                         offset = offset*2 + 4;
 567                 else
 568                         offset = offset*2;
 569                 *(__u32 *)((addr_t) &child->thread.per_info + offset) = tmp;
 570
 571         }
 572
 573         FixPerRegisters(child);
 574         return 0;
 575 }
 576
 577 static int poke_user_compat(struct task_struct *child,
 578                             addr_t addr, addr_t data)
 579 {
 580         if (!is_compat_task() || (addr & 3) || addr > sizeof(struct user32) - 3)
 581                 return -EIO;
 582
 583         return __poke_user_compat(child, addr, data);
 584 }
 585
 586 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
 587                         compat_ulong_t caddr, compat_ulong_t cdata)
 588 {
 589         unsigned long addr = caddr;
 590         unsigned long data = cdata;
 591         ptrace_area_emu31 parea;
 592         int copied, ret;
 593
 594         switch (request) {
 595         case PTRACE_PEEKUSR:
 596                 /* read the word at location addr in the USER area. */
 597                 return peek_user_compat(child, addr, data);
 598
 599         case PTRACE_POKEUSR:
 600                 /* write the word at location addr in the USER area */
 601                 return poke_user_compat(child, addr, data);
 602
 603         case PTRACE_PEEKUSR_AREA:
 604         case PTRACE_POKEUSR_AREA:
 605                 if (copy_from_user(&parea, (void __force __user *) addr,
 606                                                         sizeof(parea)))
 607                         return -EFAULT;
 608                 addr = parea.kernel_addr;
 609                 data = parea.process_addr;
 610                 copied = 0;
 611                 while (copied < parea.len) {
 612                         if (request == PTRACE_PEEKUSR_AREA)
 613                                 ret = peek_user_compat(child, addr, data);
 614                         else {
 615                                 __u32 utmp;
 616                                 if (get_user(utmp,
 617                                              (__u32 __force __user *) data))
 618                                         return -EFAULT;
 619                                 ret = poke_user_compat(child, addr, utmp);
 620                         }
 621                         if (ret)
 622                                 return ret;
 623                         addr += sizeof(unsigned int);
 624                         data += sizeof(unsigned int);
 625                         copied += sizeof(unsigned int);
 626                 }
 627                 return 0;
 628         }
 629         return compat_ptrace_request(child, request, addr, data);
 630 }
 631 #endif
 632
 633 asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
 634 {
 635         long ret;
 636
 637         /* Do the secure computing check first. */
 638         secure_computing(regs->gprs[2]);
 639
 640         /*
 641          * The sysc_tracesys code in entry.S stored the system
 642          * call number to gprs[2].
 643          */
 644         ret = regs->gprs[2];
 645         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
 646             (tracehook_report_syscall_entry(regs) ||
 647              regs->gprs[2] >= NR_syscalls)) {
 648                 /*
 649                  * Tracing decided this syscall should not happen or the
 650                  * debugger stored an invalid system call number. Skip
 651                  * the system call and the system call restart handling.
 652                  */
 653                 regs->svcnr = 0;
 654                 ret = -1;
 655         }
 656
 657         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 658                 trace_sys_enter(regs, regs->gprs[2]);
 659
 660         if (unlikely(current->audit_context))
 661                 audit_syscall_entry(is_compat_task() ?
 662                                         AUDIT_ARCH_S390 : AUDIT_ARCH_S390X,
 663                                     regs->gprs[2], regs->orig_gpr2,
 664                                     regs->gprs[3], regs->gprs[4],
 665                                     regs->gprs[5]);
 666         return ret;
 667 }
 668
 669 asmlinkage void do_syscall_trace_exit(struct pt_regs *regs)
 670 {
 671         if (unlikely(current->audit_context))
 672                 audit_syscall_exit(AUDITSC_RESULT(regs->gprs[2]),
 673                                    regs->gprs[2]);
 674
 675         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
 676                 trace_sys_exit(regs, regs->gprs[2]);
 677
 678         if (test_thread_flag(TIF_SYSCALL_TRACE))
 679                 tracehook_report_syscall_exit(regs, 0);
 680 }
 681
 682 /*
 683  * user_regset definitions.
 684  */
 685
 686 static int s390_regs_get(struct task_struct *target,
 687                          const struct user_regset *regset,
 688                          unsigned int pos, unsigned int count,
 689                          void *kbuf, void __user *ubuf)
 690 {
 691         if (target == current)
 692                 save_access_regs(target->thread.acrs);
 693
 694         if (kbuf) {
 695                 unsigned long *k = kbuf;
 696                 while (count > 0) {
 697                         *k++ = __peek_user(target, pos);
 698                         count -= sizeof(*k);
 699                         pos += sizeof(*k);
 700                 }
 701         } else {
 702                 unsigned long __user *u = ubuf;
 703                 while (count > 0) {
 704                         if (__put_user(__peek_user(target, pos), u++))
 705                                 return -EFAULT;
 706                         count -= sizeof(*u);
 707                         pos += sizeof(*u);
 708                 }
 709         }
 710         return 0;
 711 }
 712
 713 static int s390_regs_set(struct task_struct *target,
 714                          const struct user_regset *regset,
 715                          unsigned int pos, unsigned int count,
 716                          const void *kbuf, const void __user *ubuf)
 717 {
 718         int rc = 0;
 719
 720         if (target == current)
 721                 save_access_regs(target->thread.acrs);
 722
 723         if (kbuf) {
 724                 const unsigned long *k = kbuf;
 725                 while (count > 0 && !rc) {
 726                         rc = __poke_user(target, pos, *k++);
 727                         count -= sizeof(*k);
 728                         pos += sizeof(*k);
 729                 }
 730         } else {
 731                 const unsigned long  __user *u = ubuf;
 732                 while (count > 0 && !rc) {
 733                         unsigned long word;
 734                         rc = __get_user(word, u++);
 735                         if (rc)
 736                                 break;
 737                         rc = __poke_user(target, pos, word);
 738                         count -= sizeof(*u);
 739                         pos += sizeof(*u);
 740                 }
 741         }
 742
 743         if (rc == 0 && target == current)
 744                 restore_access_regs(target->thread.acrs);
 745
 746         return rc;
 747 }
 748
 749 static int s390_fpregs_get(struct task_struct *target,
 750                            const struct user_regset *regset, unsigned int pos,
 751                            unsigned int count, void *kbuf, void __user *ubuf)
 752 {
 753         if (target == current)
 754                 save_fp_regs(&target->thread.fp_regs);
 755
 756         return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 757                                    &target->thread.fp_regs, 0, -1);
 758 }
 759
 760 static int s390_fpregs_set(struct task_struct *target,
 761                            const struct user_regset *regset, unsigned int pos,
 762                            unsigned int count, const void *kbuf,
 763                            const void __user *ubuf)
 764 {
 765         int rc = 0;
 766
 767         if (target == current)
 768                 save_fp_regs(&target->thread.fp_regs);
 769
 770         /* If setting FPC, must validate it first. */
 771         if (count > 0 && pos < offsetof(s390_fp_regs, fprs)) {
 772                 u32 fpc[2] = { target->thread.fp_regs.fpc, 0 };
 773                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fpc,
 774                                         0, offsetof(s390_fp_regs, fprs));
 775                 if (rc)
 776                         return rc;
 777                 if ((fpc[0] & ~FPC_VALID_MASK) != 0 || fpc[1] != 0)
 778                         return -EINVAL;
 779                 target->thread.fp_regs.fpc = fpc[0];
 780         }
 781
 782         if (rc == 0 && count > 0)
 783                 rc = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 784                                         target->thread.fp_regs.fprs,
 785                                         offsetof(s390_fp_regs, fprs), -1);
 786
 787         if (rc == 0 && target == current)
 788                 restore_fp_regs(&target->thread.fp_regs);
 789
 790         return rc;
 791 }
 792
 793 static const struct user_regset s390_regsets[] = {
 794         [REGSET_GENERAL] = {
 795                 .core_note_type = NT_PRSTATUS,
 796                 .n = sizeof(s390_regs) / sizeof(long),
 797                 .size = sizeof(long),
 798                 .align = sizeof(long),
 799                 .get = s390_regs_get,
 800                 .set = s390_regs_set,
 801         },
 802         [REGSET_FP] = {
 803                 .core_note_type = NT_PRFPREG,
 804                 .n = sizeof(s390_fp_regs) / sizeof(long),
 805                 .size = sizeof(long),
 806                 .align = sizeof(long),
 807                 .get = s390_fpregs_get,
 808                 .set = s390_fpregs_set,
 809         },
 810 };
 811
 812 static const struct user_regset_view user_s390_view = {
 813         .name = UTS_MACHINE,
 814         .e_machine = EM_S390,
 815         .regsets = s390_regsets,
 816         .n = ARRAY_SIZE(s390_regsets)
 817 };
 818
 819 #ifdef CONFIG_COMPAT
 820 static int s390_compat_regs_get(struct task_struct *target,
 821                                 const struct user_regset *regset,
 822                                 unsigned int pos, unsigned int count,
 823                                 void *kbuf, void __user *ubuf)
 824 {
 825         if (target == current)
 826                 save_access_regs(target->thread.acrs);
 827
 828         if (kbuf) {
 829                 compat_ulong_t *k = kbuf;
 830                 while (count > 0) {
 831                         *k++ = __peek_user_compat(target, pos);
 832                         count -= sizeof(*k);
 833                         pos += sizeof(*k);
 834                 }
 835         } else {
 836                 compat_ulong_t __user *u = ubuf;
 837                 while (count > 0) {
 838                         if (__put_user(__peek_user_compat(target, pos), u++))
 839                                 return -EFAULT;
 840                         count -= sizeof(*u);
 841                         pos += sizeof(*u);
 842                 }
 843         }
 844         return 0;
 845 }
 846
 847 static int s390_compat_regs_set(struct task_struct *target,
 848                                 const struct user_regset *regset,
 849                                 unsigned int pos, unsigned int count,
 850                                 const void *kbuf, const void __user *ubuf)
 851 {
 852         int rc = 0;
 853
 854         if (target == current)
 855                 save_access_regs(target->thread.acrs);
 856
 857         if (kbuf) {
 858                 const compat_ulong_t *k = kbuf;
 859                 while (count > 0 && !rc) {
 860                         rc = __poke_user_compat(target, pos, *k++);
 861                         count -= sizeof(*k);
 862                         pos += sizeof(*k);
 863                 }
 864         } else {
 865                 const compat_ulong_t  __user *u = ubuf;
 866                 while (count > 0 && !rc) {
 867                         compat_ulong_t word;
 868                         rc = __get_user(word, u++);
 869                         if (rc)
 870                                 break;
 871                         rc = __poke_user_compat(target, pos, word);
 872                         count -= sizeof(*u);
 873                         pos += sizeof(*u);
 874                 }
 875         }
 876
 877         if (rc == 0 && target == current)
 878                 restore_access_regs(target->thread.acrs);
 879
 880         return rc;
 881 }
 882
 883 static int s390_compat_regs_high_get(struct task_struct *target,
 884                                      const struct user_regset *regset,
 885                                      unsigned int pos, unsigned int count,
 886                                      void *kbuf, void __user *ubuf)
 887 {
 888         compat_ulong_t *gprs_high;
 889
 890         gprs_high = (compat_ulong_t *)
 891                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
 892         if (kbuf) {
 893                 compat_ulong_t *k = kbuf;
 894                 while (count > 0) {
 895                         *k++ = *gprs_high;
 896                         gprs_high += 2;
 897                         count -= sizeof(*k);
 898                 }
 899         } else {
 900                 compat_ulong_t __user *u = ubuf;
 901                 while (count > 0) {
 902                         if (__put_user(*gprs_high, u++))
 903                                 return -EFAULT;
 904                         gprs_high += 2;
 905                         count -= sizeof(*u);
 906                 }
 907         }
 908         return 0;
 909 }
 910
 911 static int s390_compat_regs_high_set(struct task_struct *target,
 912                                      const struct user_regset *regset,
 913                                      unsigned int pos, unsigned int count,
 914                                      const void *kbuf, const void __user *ubuf)
 915 {
 916         compat_ulong_t *gprs_high;
 917         int rc = 0;
 918
 919         gprs_high = (compat_ulong_t *)
 920                 &task_pt_regs(target)->gprs[pos / sizeof(compat_ulong_t)];
 921         if (kbuf) {
 922                 const compat_ulong_t *k = kbuf;
 923                 while (count > 0) {
 924                         *gprs_high = *k++;
 925                         *gprs_high += 2;
 926                         count -= sizeof(*k);
 927                 }
 928         } else {
 929                 const compat_ulong_t  __user *u = ubuf;
 930                 while (count > 0 && !rc) {
 931                         unsigned long word;
 932                         rc = __get_user(word, u++);
 933                         if (rc)
 934                                 break;
 935                         *gprs_high = word;
 936                         *gprs_high += 2;
 937                         count -= sizeof(*u);
 938                 }
 939         }
 940
 941         return rc;
 942 }
 943
 944 static const struct user_regset s390_compat_regsets[] = {
 945         [REGSET_GENERAL] = {
 946                 .core_note_type = NT_PRSTATUS,
 947                 .n = sizeof(s390_compat_regs) / sizeof(compat_long_t),
 948                 .size = sizeof(compat_long_t),
 949                 .align = sizeof(compat_long_t),
 950                 .get = s390_compat_regs_get,
 951                 .set = s390_compat_regs_set,
 952         },
 953         [REGSET_FP] = {
 954                 .core_note_type = NT_PRFPREG,
 955                 .n = sizeof(s390_fp_regs) / sizeof(compat_long_t),
 956                 .size = sizeof(compat_long_t),
 957                 .align = sizeof(compat_long_t),
 958                 .get = s390_fpregs_get,
 959                 .set = s390_fpregs_set,
 960         },
 961         [REGSET_GENERAL_EXTENDED] = {
 962                 .core_note_type = NT_S390_HIGH_GPRS,
 963                 .n = sizeof(s390_compat_regs_high) / sizeof(compat_long_t),
 964                 .size = sizeof(compat_long_t),
 965                 .align = sizeof(compat_long_t),
 966                 .get = s390_compat_regs_high_get,
 967                 .set = s390_compat_regs_high_set,
 968         },
 969 };
 970
 971 static const struct user_regset_view user_s390_compat_view = {
 972         .name = "s390",
 973         .e_machine = EM_S390,
 974         .regsets = s390_compat_regsets,
 975         .n = ARRAY_SIZE(s390_compat_regsets)
 976 };
 977 #endif
 978
 979 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 980 {
 981 #ifdef CONFIG_COMPAT
 982         if (test_tsk_thread_flag(task, TIF_31BIT))
 983                 return &user_s390_compat_view;
 984 #endif
 985         return &user_s390_view;
 986 }