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