kernel/compat.c

   1 /*
   2  *  linux/kernel/compat.c
   3  *
   4  *  Kernel compatibililty routines for e.g. 32 bit syscall support
   5  *  on 64 bit kernels.
   6  *
   7  *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License version 2 as
  11  *  published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/linkage.h>
  15 #include <linux/compat.h>
  16 #include <linux/errno.h>
  17 #include <linux/time.h>
  18 #include <linux/signal.h>
  19 #include <linux/sched.h>        /* for MAX_SCHEDULE_TIMEOUT */
  20 #include <linux/syscalls.h>
  21 #include <linux/unistd.h>
  22 #include <linux/security.h>
  23 #include <linux/timex.h>
  24 #include <linux/export.h>
  25 #include <linux/migrate.h>
  26 #include <linux/posix-timers.h>
  27 #include <linux/times.h>
  28 #include <linux/ptrace.h>
  29 #include <linux/gfp.h>
  30
  31 #include <asm/uaccess.h>
  32
  33 /*
  34  * Get/set struct timeval with struct timespec on the native side
  35  */
  36 static int compat_get_timeval_convert(struct timespec *o,
  37                                       struct compat_timeval __user *i)
  38 {
  39         long usec;
  40
  41         if (get_user(o->tv_sec, &i->tv_sec) ||
  42             get_user(usec, &i->tv_usec))
  43                 return -EFAULT;
  44         o->tv_nsec = usec * 1000;
  45         return 0;
  46 }
  47
  48 static int compat_put_timeval_convert(struct compat_timeval __user *o,
  49                                       struct timeval *i)
  50 {
  51         return (put_user(i->tv_sec, &o->tv_sec) ||
  52                 put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
  53 }
  54
  55 static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
  56 {
  57         memset(txc, 0, sizeof(struct timex));
  58
  59         if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
  60                         __get_user(txc->modes, &utp->modes) ||
  61                         __get_user(txc->offset, &utp->offset) ||
  62                         __get_user(txc->freq, &utp->freq) ||
  63                         __get_user(txc->maxerror, &utp->maxerror) ||
  64                         __get_user(txc->esterror, &utp->esterror) ||
  65                         __get_user(txc->status, &utp->status) ||
  66                         __get_user(txc->constant, &utp->constant) ||
  67                         __get_user(txc->precision, &utp->precision) ||
  68                         __get_user(txc->tolerance, &utp->tolerance) ||
  69                         __get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
  70                         __get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
  71                         __get_user(txc->tick, &utp->tick) ||
  72                         __get_user(txc->ppsfreq, &utp->ppsfreq) ||
  73                         __get_user(txc->jitter, &utp->jitter) ||
  74                         __get_user(txc->shift, &utp->shift) ||
  75                         __get_user(txc->stabil, &utp->stabil) ||
  76                         __get_user(txc->jitcnt, &utp->jitcnt) ||
  77                         __get_user(txc->calcnt, &utp->calcnt) ||
  78                         __get_user(txc->errcnt, &utp->errcnt) ||
  79                         __get_user(txc->stbcnt, &utp->stbcnt))
  80                 return -EFAULT;
  81
  82         return 0;
  83 }
  84
  85 static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
  86 {
  87         if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
  88                         __put_user(txc->modes, &utp->modes) ||
  89                         __put_user(txc->offset, &utp->offset) ||
  90                         __put_user(txc->freq, &utp->freq) ||
  91                         __put_user(txc->maxerror, &utp->maxerror) ||
  92                         __put_user(txc->esterror, &utp->esterror) ||
  93                         __put_user(txc->status, &utp->status) ||
  94                         __put_user(txc->constant, &utp->constant) ||
  95                         __put_user(txc->precision, &utp->precision) ||
  96                         __put_user(txc->tolerance, &utp->tolerance) ||
  97                         __put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
  98                         __put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
  99                         __put_user(txc->tick, &utp->tick) ||
 100                         __put_user(txc->ppsfreq, &utp->ppsfreq) ||
 101                         __put_user(txc->jitter, &utp->jitter) ||
 102                         __put_user(txc->shift, &utp->shift) ||
 103                         __put_user(txc->stabil, &utp->stabil) ||
 104                         __put_user(txc->jitcnt, &utp->jitcnt) ||
 105                         __put_user(txc->calcnt, &utp->calcnt) ||
 106                         __put_user(txc->errcnt, &utp->errcnt) ||
 107                         __put_user(txc->stbcnt, &utp->stbcnt) ||
 108                         __put_user(txc->tai, &utp->tai))
 109                 return -EFAULT;
 110         return 0;
 111 }
 112
 113 asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
 114                 struct timezone __user *tz)
 115 {
 116         if (tv) {
 117                 struct timeval ktv;
 118                 do_gettimeofday(&ktv);
 119                 if (compat_put_timeval_convert(tv, &ktv))
 120                         return -EFAULT;
 121         }
 122         if (tz) {
 123                 if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
 124                         return -EFAULT;
 125         }
 126
 127         return 0;
 128 }
 129
 130 asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
 131                 struct timezone __user *tz)
 132 {
 133         struct timespec kts;
 134         struct timezone ktz;
 135
 136         if (tv) {
 137                 if (compat_get_timeval_convert(&kts, tv))
 138                         return -EFAULT;
 139         }
 140         if (tz) {
 141                 if (copy_from_user(&ktz, tz, sizeof(ktz)))
 142                         return -EFAULT;
 143         }
 144
 145         return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
 146 }
 147
 148 int get_compat_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
 149 {
 150         return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
 151                         __get_user(tv->tv_sec, &ctv->tv_sec) ||
 152                         __get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 153 }
 154 EXPORT_SYMBOL_GPL(get_compat_timeval);
 155
 156 int put_compat_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
 157 {
 158         return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
 159                         __put_user(tv->tv_sec, &ctv->tv_sec) ||
 160                         __put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 161 }
 162 EXPORT_SYMBOL_GPL(put_compat_timeval);
 163
 164 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
 165 {
 166         return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
 167                         __get_user(ts->tv_sec, &cts->tv_sec) ||
 168                         __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 169 }
 170 EXPORT_SYMBOL_GPL(get_compat_timespec);
 171
 172 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
 173 {
 174         return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
 175                         __put_user(ts->tv_sec, &cts->tv_sec) ||
 176                         __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 177 }
 178 EXPORT_SYMBOL_GPL(put_compat_timespec);
 179
 180 int compat_get_timeval(struct timeval *tv, const void __user *utv)
 181 {
 182         if (COMPAT_USE_64BIT_TIME)
 183                 return copy_from_user(tv, utv, sizeof *tv) ? -EFAULT : 0;
 184         else
 185                 return get_compat_timeval(tv, utv);
 186 }
 187 EXPORT_SYMBOL_GPL(compat_get_timeval);
 188
 189 int compat_put_timeval(const struct timeval *tv, void __user *utv)
 190 {
 191         if (COMPAT_USE_64BIT_TIME)
 192                 return copy_to_user(utv, tv, sizeof *tv) ? -EFAULT : 0;
 193         else
 194                 return put_compat_timeval(tv, utv);
 195 }
 196 EXPORT_SYMBOL_GPL(compat_put_timeval);
 197
 198 int compat_get_timespec(struct timespec *ts, const void __user *uts)
 199 {
 200         if (COMPAT_USE_64BIT_TIME)
 201                 return copy_from_user(ts, uts, sizeof *ts) ? -EFAULT : 0;
 202         else
 203                 return get_compat_timespec(ts, uts);
 204 }
 205 EXPORT_SYMBOL_GPL(compat_get_timespec);
 206
 207 int compat_put_timespec(const struct timespec *ts, void __user *uts)
 208 {
 209         if (COMPAT_USE_64BIT_TIME)
 210                 return copy_to_user(uts, ts, sizeof *ts) ? -EFAULT : 0;
 211         else
 212                 return put_compat_timespec(ts, uts);
 213 }
 214 EXPORT_SYMBOL_GPL(compat_put_timespec);
 215
 216 static long compat_nanosleep_restart(struct restart_block *restart)
 217 {
 218         struct compat_timespec __user *rmtp;
 219         struct timespec rmt;
 220         mm_segment_t oldfs;
 221         long ret;
 222
 223         restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
 224         oldfs = get_fs();
 225         set_fs(KERNEL_DS);
 226         ret = hrtimer_nanosleep_restart(restart);
 227         set_fs(oldfs);
 228
 229         if (ret) {
 230                 rmtp = restart->nanosleep.compat_rmtp;
 231
 232                 if (rmtp && put_compat_timespec(&rmt, rmtp))
 233                         return -EFAULT;
 234         }
 235
 236         return ret;
 237 }
 238
 239 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
 240                                      struct compat_timespec __user *rmtp)
 241 {
 242         struct timespec tu, rmt;
 243         mm_segment_t oldfs;
 244         long ret;
 245
 246         if (get_compat_timespec(&tu, rqtp))
 247                 return -EFAULT;
 248
 249         if (!timespec_valid(&tu))
 250                 return -EINVAL;
 251
 252         oldfs = get_fs();
 253         set_fs(KERNEL_DS);
 254         ret = hrtimer_nanosleep(&tu,
 255                                 rmtp ? (struct timespec __user *)&rmt : NULL,
 256                                 HRTIMER_MODE_REL, CLOCK_MONOTONIC);
 257         set_fs(oldfs);
 258
 259         if (ret) {
 260                 struct restart_block *restart
 261                         = &current_thread_info()->restart_block;
 262
 263                 restart->fn = compat_nanosleep_restart;
 264                 restart->nanosleep.compat_rmtp = rmtp;
 265
 266                 if (rmtp && put_compat_timespec(&rmt, rmtp))
 267                         return -EFAULT;
 268         }
 269
 270         return ret;
 271 }
 272
 273 static inline long get_compat_itimerval(struct itimerval *o,
 274                 struct compat_itimerval __user *i)
 275 {
 276         return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
 277                 (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
 278                  __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
 279                  __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
 280                  __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
 281 }
 282
 283 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
 284                 struct itimerval *i)
 285 {
 286         return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
 287                 (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
 288                  __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
 289                  __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
 290                  __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
 291 }
 292
 293 asmlinkage long compat_sys_getitimer(int which,
 294                 struct compat_itimerval __user *it)
 295 {
 296         struct itimerval kit;
 297         int error;
 298
 299         error = do_getitimer(which, &kit);
 300         if (!error && put_compat_itimerval(it, &kit))
 301                 error = -EFAULT;
 302         return error;
 303 }
 304
 305 asmlinkage long compat_sys_setitimer(int which,
 306                 struct compat_itimerval __user *in,
 307                 struct compat_itimerval __user *out)
 308 {
 309         struct itimerval kin, kout;
 310         int error;
 311
 312         if (in) {
 313                 if (get_compat_itimerval(&kin, in))
 314                         return -EFAULT;
 315         } else
 316                 memset(&kin, 0, sizeof(kin));
 317
 318         error = do_setitimer(which, &kin, out ? &kout : NULL);
 319         if (error || !out)
 320                 return error;
 321         if (put_compat_itimerval(out, &kout))
 322                 return -EFAULT;
 323         return 0;
 324 }
 325
 326 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
 327 {
 328         return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
 329 }
 330
 331 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
 332 {
 333         if (tbuf) {
 334                 struct tms tms;
 335                 struct compat_tms tmp;
 336
 337                 do_sys_times(&tms);
 338                 /* Convert our struct tms to the compat version. */
 339                 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
 340                 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
 341                 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
 342                 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
 343                 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
 344                         return -EFAULT;
 345         }
 346         force_successful_syscall_return();
 347         return compat_jiffies_to_clock_t(jiffies);
 348 }
 349
 350 #ifdef __ARCH_WANT_SYS_SIGPENDING
 351
 352 /*
 353  * Assumption: old_sigset_t and compat_old_sigset_t are both
 354  * types that can be passed to put_user()/get_user().
 355  */
 356
 357 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
 358 {
 359         old_sigset_t s;
 360         long ret;
 361         mm_segment_t old_fs = get_fs();
 362
 363         set_fs(KERNEL_DS);
 364         ret = sys_sigpending((old_sigset_t __user *) &s);
 365         set_fs(old_fs);
 366         if (ret == 0)
 367                 ret = put_user(s, set);
 368         return ret;
 369 }
 370
 371 #endif
 372
 373 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
 374
 375 /*
 376  * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
 377  * blocked set of signals to the supplied signal set
 378  */
 379 static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
 380 {
 381         memcpy(blocked->sig, &set, sizeof(set));
 382 }
 383
 384 asmlinkage long compat_sys_sigprocmask(int how,
 385                                        compat_old_sigset_t __user *nset,
 386                                        compat_old_sigset_t __user *oset)
 387 {
 388         old_sigset_t old_set, new_set;
 389         sigset_t new_blocked;
 390
 391         old_set = current->blocked.sig[0];
 392
 393         if (nset) {
 394                 if (get_user(new_set, nset))
 395                         return -EFAULT;
 396                 new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
 397
 398                 new_blocked = current->blocked;
 399
 400                 switch (how) {
 401                 case SIG_BLOCK:
 402                         sigaddsetmask(&new_blocked, new_set);
 403                         break;
 404                 case SIG_UNBLOCK:
 405                         sigdelsetmask(&new_blocked, new_set);
 406                         break;
 407                 case SIG_SETMASK:
 408                         compat_sig_setmask(&new_blocked, new_set);
 409                         break;
 410                 default:
 411                         return -EINVAL;
 412                 }
 413
 414                 set_current_blocked(&new_blocked);
 415         }
 416
 417         if (oset) {
 418                 if (put_user(old_set, oset))
 419                         return -EFAULT;
 420         }
 421
 422         return 0;
 423 }
 424
 425 #endif
 426
 427 asmlinkage long compat_sys_setrlimit(unsigned int resource,
 428                 struct compat_rlimit __user *rlim)
 429 {
 430         struct rlimit r;
 431
 432         if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
 433             __get_user(r.rlim_cur, &rlim->rlim_cur) ||
 434             __get_user(r.rlim_max, &rlim->rlim_max))
 435                 return -EFAULT;
 436
 437         if (r.rlim_cur == COMPAT_RLIM_INFINITY)
 438                 r.rlim_cur = RLIM_INFINITY;
 439         if (r.rlim_max == COMPAT_RLIM_INFINITY)
 440                 r.rlim_max = RLIM_INFINITY;
 441         return do_prlimit(current, resource, &r, NULL);
 442 }
 443
 444 #ifdef COMPAT_RLIM_OLD_INFINITY
 445
 446 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
 447                 struct compat_rlimit __user *rlim)
 448 {
 449         struct rlimit r;
 450         int ret;
 451         mm_segment_t old_fs = get_fs();
 452
 453         set_fs(KERNEL_DS);
 454         ret = sys_old_getrlimit(resource, &r);
 455         set_fs(old_fs);
 456
 457         if (!ret) {
 458                 if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
 459                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 460                 if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
 461                         r.rlim_max = COMPAT_RLIM_INFINITY;
 462
 463                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 464                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 465                     __put_user(r.rlim_max, &rlim->rlim_max))
 466                         return -EFAULT;
 467         }
 468         return ret;
 469 }
 470
 471 #endif
 472
 473 asmlinkage long compat_sys_getrlimit(unsigned int resource,
 474                 struct compat_rlimit __user *rlim)
 475 {
 476         struct rlimit r;
 477         int ret;
 478
 479         ret = do_prlimit(current, resource, NULL, &r);
 480         if (!ret) {
 481                 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
 482                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 483                 if (r.rlim_max > COMPAT_RLIM_INFINITY)
 484                         r.rlim_max = COMPAT_RLIM_INFINITY;
 485
 486                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 487                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 488                     __put_user(r.rlim_max, &rlim->rlim_max))
 489                         return -EFAULT;
 490         }
 491         return ret;
 492 }
 493
 494 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 495 {
 496         if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
 497             __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
 498             __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
 499             __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
 500             __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
 501             __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
 502             __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
 503             __put_user(r->ru_idrss, &ru->ru_idrss) ||
 504             __put_user(r->ru_isrss, &ru->ru_isrss) ||
 505             __put_user(r->ru_minflt, &ru->ru_minflt) ||
 506             __put_user(r->ru_majflt, &ru->ru_majflt) ||
 507             __put_user(r->ru_nswap, &ru->ru_nswap) ||
 508             __put_user(r->ru_inblock, &ru->ru_inblock) ||
 509             __put_user(r->ru_oublock, &ru->ru_oublock) ||
 510             __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
 511             __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
 512             __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
 513             __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
 514             __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
 515                 return -EFAULT;
 516         return 0;
 517 }
 518
 519 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
 520 {
 521         struct rusage r;
 522         int ret;
 523         mm_segment_t old_fs = get_fs();
 524
 525         set_fs(KERNEL_DS);
 526         ret = sys_getrusage(who, (struct rusage __user *) &r);
 527         set_fs(old_fs);
 528
 529         if (ret)
 530                 return ret;
 531
 532         if (put_compat_rusage(&r, ru))
 533                 return -EFAULT;
 534
 535         return 0;
 536 }
 537
 538 asmlinkage long
 539 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
 540         struct compat_rusage __user *ru)
 541 {
 542         if (!ru) {
 543                 return sys_wait4(pid, stat_addr, options, NULL);
 544         } else {
 545                 struct rusage r;
 546                 int ret;
 547                 unsigned int status;
 548                 mm_segment_t old_fs = get_fs();
 549
 550                 set_fs (KERNEL_DS);
 551                 ret = sys_wait4(pid,
 552                                 (stat_addr ?
 553                                  (unsigned int __user *) &status : NULL),
 554                                 options, (struct rusage __user *) &r);
 555                 set_fs (old_fs);
 556
 557                 if (ret > 0) {
 558                         if (put_compat_rusage(&r, ru))
 559                                 return -EFAULT;
 560                         if (stat_addr && put_user(status, stat_addr))
 561                                 return -EFAULT;
 562                 }
 563                 return ret;
 564         }
 565 }
 566
 567 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
 568                 struct compat_siginfo __user *uinfo, int options,
 569                 struct compat_rusage __user *uru)
 570 {
 571         siginfo_t info;
 572         struct rusage ru;
 573         long ret;
 574         mm_segment_t old_fs = get_fs();
 575
 576         memset(&info, 0, sizeof(info));
 577
 578         set_fs(KERNEL_DS);
 579         ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 580                          uru ? (struct rusage __user *)&ru : NULL);
 581         set_fs(old_fs);
 582
 583         if ((ret < 0) || (info.si_signo == 0))
 584                 return ret;
 585
 586         if (uru) {
 587                 ret = put_compat_rusage(&ru, uru);
 588                 if (ret)
 589                         return ret;
 590         }
 591
 592         BUG_ON(info.si_code & __SI_MASK);
 593         info.si_code |= __SI_CHLD;
 594         return copy_siginfo_to_user32(uinfo, &info);
 595 }
 596
 597 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 598                                     unsigned len, struct cpumask *new_mask)
 599 {
 600         unsigned long *k;
 601
 602         if (len < cpumask_size())
 603                 memset(new_mask, 0, cpumask_size());
 604         else if (len > cpumask_size())
 605                 len = cpumask_size();
 606
 607         k = cpumask_bits(new_mask);
 608         return compat_get_bitmap(k, user_mask_ptr, len * 8);
 609 }
 610
 611 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
 612                                              unsigned int len,
 613                                              compat_ulong_t __user *user_mask_ptr)
 614 {
 615         cpumask_var_t new_mask;
 616         int retval;
 617
 618         if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
 619                 return -ENOMEM;
 620
 621         retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
 622         if (retval)
 623                 goto out;
 624
 625         retval = sched_setaffinity(pid, new_mask);
 626 out:
 627         free_cpumask_var(new_mask);
 628         return retval;
 629 }
 630
 631 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 632                                              compat_ulong_t __user *user_mask_ptr)
 633 {
 634         int ret;
 635         cpumask_var_t mask;
 636
 637         if ((len * BITS_PER_BYTE) < nr_cpu_ids)
 638                 return -EINVAL;
 639         if (len & (sizeof(compat_ulong_t)-1))
 640                 return -EINVAL;
 641
 642         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 643                 return -ENOMEM;
 644
 645         ret = sched_getaffinity(pid, mask);
 646         if (ret == 0) {
 647                 size_t retlen = min_t(size_t, len, cpumask_size());
 648
 649                 if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
 650                         ret = -EFAULT;
 651                 else
 652                         ret = retlen;
 653         }
 654         free_cpumask_var(mask);
 655
 656         return ret;
 657 }
 658
 659 int get_compat_itimerspec(struct itimerspec *dst,
 660                           const struct compat_itimerspec __user *src)
 661 {
 662         if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
 663             get_compat_timespec(&dst->it_value, &src->it_value))
 664                 return -EFAULT;
 665         return 0;
 666 }
 667
 668 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 669                           const struct itimerspec *src)
 670 {
 671         if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
 672             put_compat_timespec(&src->it_value, &dst->it_value))
 673                 return -EFAULT;
 674         return 0;
 675 }
 676
 677 long compat_sys_timer_create(clockid_t which_clock,
 678                         struct compat_sigevent __user *timer_event_spec,
 679                         timer_t __user *created_timer_id)
 680 {
 681         struct sigevent __user *event = NULL;
 682
 683         if (timer_event_spec) {
 684                 struct sigevent kevent;
 685
 686                 event = compat_alloc_user_space(sizeof(*event));
 687                 if (get_compat_sigevent(&kevent, timer_event_spec) ||
 688                     copy_to_user(event, &kevent, sizeof(*event)))
 689                         return -EFAULT;
 690         }
 691
 692         return sys_timer_create(which_clock, event, created_timer_id);
 693 }
 694
 695 long compat_sys_timer_settime(timer_t timer_id, int flags,
 696                           struct compat_itimerspec __user *new,
 697                           struct compat_itimerspec __user *old)
 698 {
 699         long err;
 700         mm_segment_t oldfs;
 701         struct itimerspec newts, oldts;
 702
 703         if (!new)
 704                 return -EINVAL;
 705         if (get_compat_itimerspec(&newts, new))
 706                 return -EFAULT;
 707         oldfs = get_fs();
 708         set_fs(KERNEL_DS);
 709         err = sys_timer_settime(timer_id, flags,
 710                                 (struct itimerspec __user *) &newts,
 711                                 (struct itimerspec __user *) &oldts);
 712         set_fs(oldfs);
 713         if (!err && old && put_compat_itimerspec(old, &oldts))
 714                 return -EFAULT;
 715         return err;
 716 }
 717
 718 long compat_sys_timer_gettime(timer_t timer_id,
 719                 struct compat_itimerspec __user *setting)
 720 {
 721         long err;
 722         mm_segment_t oldfs;
 723         struct itimerspec ts;
 724
 725         oldfs = get_fs();
 726         set_fs(KERNEL_DS);
 727         err = sys_timer_gettime(timer_id,
 728                                 (struct itimerspec __user *) &ts);
 729         set_fs(oldfs);
 730         if (!err && put_compat_itimerspec(setting, &ts))
 731                 return -EFAULT;
 732         return err;
 733 }
 734
 735 long compat_sys_clock_settime(clockid_t which_clock,
 736                 struct compat_timespec __user *tp)
 737 {
 738         long err;
 739         mm_segment_t oldfs;
 740         struct timespec ts;
 741
 742         if (get_compat_timespec(&ts, tp))
 743                 return -EFAULT;
 744         oldfs = get_fs();
 745         set_fs(KERNEL_DS);
 746         err = sys_clock_settime(which_clock,
 747                                 (struct timespec __user *) &ts);
 748         set_fs(oldfs);
 749         return err;
 750 }
 751
 752 long compat_sys_clock_gettime(clockid_t which_clock,
 753                 struct compat_timespec __user *tp)
 754 {
 755         long err;
 756         mm_segment_t oldfs;
 757         struct timespec ts;
 758
 759         oldfs = get_fs();
 760         set_fs(KERNEL_DS);
 761         err = sys_clock_gettime(which_clock,
 762                                 (struct timespec __user *) &ts);
 763         set_fs(oldfs);
 764         if (!err && put_compat_timespec(&ts, tp))
 765                 return -EFAULT;
 766         return err;
 767 }
 768
 769 long compat_sys_clock_adjtime(clockid_t which_clock,
 770                 struct compat_timex __user *utp)
 771 {
 772         struct timex txc;
 773         mm_segment_t oldfs;
 774         int err, ret;
 775
 776         err = compat_get_timex(&txc, utp);
 777         if (err)
 778                 return err;
 779
 780         oldfs = get_fs();
 781         set_fs(KERNEL_DS);
 782         ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
 783         set_fs(oldfs);
 784
 785         err = compat_put_timex(utp, &txc);
 786         if (err)
 787                 return err;
 788
 789         return ret;
 790 }
 791
 792 long compat_sys_clock_getres(clockid_t which_clock,
 793                 struct compat_timespec __user *tp)
 794 {
 795         long err;
 796         mm_segment_t oldfs;
 797         struct timespec ts;
 798
 799         oldfs = get_fs();
 800         set_fs(KERNEL_DS);
 801         err = sys_clock_getres(which_clock,
 802                                (struct timespec __user *) &ts);
 803         set_fs(oldfs);
 804         if (!err && tp && put_compat_timespec(&ts, tp))
 805                 return -EFAULT;
 806         return err;
 807 }
 808
 809 static long compat_clock_nanosleep_restart(struct restart_block *restart)
 810 {
 811         long err;
 812         mm_segment_t oldfs;
 813         struct timespec tu;
 814         struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
 815
 816         restart->nanosleep.rmtp = (struct timespec __user *) &tu;
 817         oldfs = get_fs();
 818         set_fs(KERNEL_DS);
 819         err = clock_nanosleep_restart(restart);
 820         set_fs(oldfs);
 821
 822         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 823             put_compat_timespec(&tu, rmtp))
 824                 return -EFAULT;
 825
 826         if (err == -ERESTART_RESTARTBLOCK) {
 827                 restart->fn = compat_clock_nanosleep_restart;
 828                 restart->nanosleep.compat_rmtp = rmtp;
 829         }
 830         return err;
 831 }
 832
 833 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
 834                             struct compat_timespec __user *rqtp,
 835                             struct compat_timespec __user *rmtp)
 836 {
 837         long err;
 838         mm_segment_t oldfs;
 839         struct timespec in, out;
 840         struct restart_block *restart;
 841
 842         if (get_compat_timespec(&in, rqtp))
 843                 return -EFAULT;
 844
 845         oldfs = get_fs();
 846         set_fs(KERNEL_DS);
 847         err = sys_clock_nanosleep(which_clock, flags,
 848                                   (struct timespec __user *) &in,
 849                                   (struct timespec __user *) &out);
 850         set_fs(oldfs);
 851
 852         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 853             put_compat_timespec(&out, rmtp))
 854                 return -EFAULT;
 855
 856         if (err == -ERESTART_RESTARTBLOCK) {
 857                 restart = &current_thread_info()->restart_block;
 858                 restart->fn = compat_clock_nanosleep_restart;
 859                 restart->nanosleep.compat_rmtp = rmtp;
 860         }
 861         return err;
 862 }
 863
 864 /*
 865  * We currently only need the following fields from the sigevent
 866  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 867  * sigev_notify_thread_id).  The others are handled in user mode.
 868  * We also assume that copying sigev_value.sival_int is sufficient
 869  * to keep all the bits of sigev_value.sival_ptr intact.
 870  */
 871 int get_compat_sigevent(struct sigevent *event,
 872                 const struct compat_sigevent __user *u_event)
 873 {
 874         memset(event, 0, sizeof(*event));
 875         return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 876                 __get_user(event->sigev_value.sival_int,
 877                         &u_event->sigev_value.sival_int) ||
 878                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
 879                 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
 880                 __get_user(event->sigev_notify_thread_id,
 881                         &u_event->sigev_notify_thread_id))
 882                 ? -EFAULT : 0;
 883 }
 884
 885 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 886                        unsigned long bitmap_size)
 887 {
 888         int i, j;
 889         unsigned long m;
 890         compat_ulong_t um;
 891         unsigned long nr_compat_longs;
 892
 893         /* align bitmap up to nearest compat_long_t boundary */
 894         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 895
 896         if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 897                 return -EFAULT;
 898
 899         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 900
 901         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 902                 m = 0;
 903
 904                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 905                         /*
 906                          * We dont want to read past the end of the userspace
 907                          * bitmap. We must however ensure the end of the
 908                          * kernel bitmap is zeroed.
 909                          */
 910                         if (nr_compat_longs-- > 0) {
 911                                 if (__get_user(um, umask))
 912                                         return -EFAULT;
 913                         } else {
 914                                 um = 0;
 915                         }
 916
 917                         umask++;
 918                         m |= (long)um << (j * BITS_PER_COMPAT_LONG);
 919                 }
 920                 *mask++ = m;
 921         }
 922
 923         return 0;
 924 }
 925
 926 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 927                        unsigned long bitmap_size)
 928 {
 929         int i, j;
 930         unsigned long m;
 931         compat_ulong_t um;
 932         unsigned long nr_compat_longs;
 933
 934         /* align bitmap up to nearest compat_long_t boundary */
 935         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 936
 937         if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 938                 return -EFAULT;
 939
 940         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 941
 942         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 943                 m = *mask++;
 944
 945                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 946                         um = m;
 947
 948                         /*
 949                          * We dont want to write past the end of the userspace
 950                          * bitmap.
 951                          */
 952                         if (nr_compat_longs-- > 0) {
 953                                 if (__put_user(um, umask))
 954                                         return -EFAULT;
 955                         }
 956
 957                         umask++;
 958                         m >>= 4*sizeof(um);
 959                         m >>= 4*sizeof(um);
 960                 }
 961         }
 962
 963         return 0;
 964 }
 965
 966 void
 967 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
 968 {
 969         switch (_NSIG_WORDS) {
 970         case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
 971         case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
 972         case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
 973         case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
 974         }
 975 }
 976 EXPORT_SYMBOL_GPL(sigset_from_compat);
 977
 978 asmlinkage long
 979 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
 980                 struct compat_siginfo __user *uinfo,
 981                 struct compat_timespec __user *uts, compat_size_t sigsetsize)
 982 {
 983         compat_sigset_t s32;
 984         sigset_t s;
 985         struct timespec t;
 986         siginfo_t info;
 987         long ret;
 988
 989         if (sigsetsize != sizeof(sigset_t))
 990                 return -EINVAL;
 991
 992         if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
 993                 return -EFAULT;
 994         sigset_from_compat(&s, &s32);
 995
 996         if (uts) {
 997                 if (get_compat_timespec(&t, uts))
 998                         return -EFAULT;
 999         }
1000
1001         ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1002
1003         if (ret > 0 && uinfo) {
1004                 if (copy_siginfo_to_user32(uinfo, &info))
1005                         ret = -EFAULT;
1006         }
1007
1008         return ret;
1009
1010 }
1011
1012 asmlinkage long
1013 compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig,
1014                              struct compat_siginfo __user *uinfo)
1015 {
1016         siginfo_t info;
1017
1018         if (copy_siginfo_from_user32(&info, uinfo))
1019                 return -EFAULT;
1020         return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
1021 }
1022
1023 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1024
1025 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1026
1027 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
1028 {
1029         compat_time_t i;
1030         struct timeval tv;
1031
1032         do_gettimeofday(&tv);
1033         i = tv.tv_sec;
1034
1035         if (tloc) {
1036                 if (put_user(i,tloc))
1037                         return -EFAULT;
1038         }
1039         force_successful_syscall_return();
1040         return i;
1041 }
1042
1043 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
1044 {
1045         struct timespec tv;
1046         int err;
1047
1048         if (get_user(tv.tv_sec, tptr))
1049                 return -EFAULT;
1050
1051         tv.tv_nsec = 0;
1052
1053         err = security_settime(&tv, NULL);
1054         if (err)
1055                 return err;
1056
1057         do_settimeofday(&tv);
1058         return 0;
1059 }
1060
1061 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1062
1063 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
1064 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
1065 {
1066         sigset_t newset;
1067         compat_sigset_t newset32;
1068
1069         /* XXX: Don't preclude handling different sized sigset_t's.  */
1070         if (sigsetsize != sizeof(sigset_t))
1071                 return -EINVAL;
1072
1073         if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
1074                 return -EFAULT;
1075         sigset_from_compat(&newset, &newset32);
1076         return sigsuspend(&newset);
1077 }
1078 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
1079
1080 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
1081 {
1082         struct timex txc;
1083         int err, ret;
1084
1085         err = compat_get_timex(&txc, utp);
1086         if (err)
1087                 return err;
1088
1089         ret = do_adjtimex(&txc);
1090
1091         err = compat_put_timex(utp, &txc);
1092         if (err)
1093                 return err;
1094
1095         return ret;
1096 }
1097
1098 #ifdef CONFIG_NUMA
1099 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1100                 compat_uptr_t __user *pages32,
1101                 const int __user *nodes,
1102                 int __user *status,
1103                 int flags)
1104 {
1105         const void __user * __user *pages;
1106         int i;
1107
1108         pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1109         for (i = 0; i < nr_pages; i++) {
1110                 compat_uptr_t p;
1111
1112                 if (get_user(p, pages32 + i) ||
1113                         put_user(compat_ptr(p), pages + i))
1114                         return -EFAULT;
1115         }
1116         return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1117 }
1118
1119 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1120                         compat_ulong_t maxnode,
1121                         const compat_ulong_t __user *old_nodes,
1122                         const compat_ulong_t __user *new_nodes)
1123 {
1124         unsigned long __user *old = NULL;
1125         unsigned long __user *new = NULL;
1126         nodemask_t tmp_mask;
1127         unsigned long nr_bits;
1128         unsigned long size;
1129
1130         nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1131         size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1132         if (old_nodes) {
1133                 if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1134                         return -EFAULT;
1135                 old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1136                 if (new_nodes)
1137                         new = old + size / sizeof(unsigned long);
1138                 if (copy_to_user(old, nodes_addr(tmp_mask), size))
1139                         return -EFAULT;
1140         }
1141         if (new_nodes) {
1142                 if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1143                         return -EFAULT;
1144                 if (new == NULL)
1145                         new = compat_alloc_user_space(size);
1146                 if (copy_to_user(new, nodes_addr(tmp_mask), size))
1147                         return -EFAULT;
1148         }
1149         return sys_migrate_pages(pid, nr_bits + 1, old, new);
1150 }
1151 #endif
1152
1153 struct compat_sysinfo {
1154         s32 uptime;
1155         u32 loads[3];
1156         u32 totalram;
1157         u32 freeram;
1158         u32 sharedram;
1159         u32 bufferram;
1160         u32 totalswap;
1161         u32 freeswap;
1162         u16 procs;
1163         u16 pad;
1164         u32 totalhigh;
1165         u32 freehigh;
1166         u32 mem_unit;
1167         char _f[20-2*sizeof(u32)-sizeof(int)];
1168 };
1169
1170 asmlinkage long
1171 compat_sys_sysinfo(struct compat_sysinfo __user *info)
1172 {
1173         struct sysinfo s;
1174
1175         do_sysinfo(&s);
1176
1177         /* Check to see if any memory value is too large for 32-bit and scale
1178          *  down if needed
1179          */
1180         if ((s.totalram >> 32) || (s.totalswap >> 32)) {
1181                 int bitcount = 0;
1182
1183                 while (s.mem_unit < PAGE_SIZE) {
1184                         s.mem_unit <<= 1;
1185                         bitcount++;
1186                 }
1187
1188                 s.totalram >>= bitcount;
1189                 s.freeram >>= bitcount;
1190                 s.sharedram >>= bitcount;
1191                 s.bufferram >>= bitcount;
1192                 s.totalswap >>= bitcount;
1193                 s.freeswap >>= bitcount;
1194                 s.totalhigh >>= bitcount;
1195                 s.freehigh >>= bitcount;
1196         }
1197
1198         if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
1199             __put_user (s.uptime, &info->uptime) ||
1200             __put_user (s.loads[0], &info->loads[0]) ||
1201             __put_user (s.loads[1], &info->loads[1]) ||
1202             __put_user (s.loads[2], &info->loads[2]) ||
1203             __put_user (s.totalram, &info->totalram) ||
1204             __put_user (s.freeram, &info->freeram) ||
1205             __put_user (s.sharedram, &info->sharedram) ||
1206             __put_user (s.bufferram, &info->bufferram) ||
1207             __put_user (s.totalswap, &info->totalswap) ||
1208             __put_user (s.freeswap, &info->freeswap) ||
1209             __put_user (s.procs, &info->procs) ||
1210             __put_user (s.totalhigh, &info->totalhigh) ||
1211             __put_user (s.freehigh, &info->freehigh) ||
1212             __put_user (s.mem_unit, &info->mem_unit))
1213                 return -EFAULT;
1214
1215         return 0;
1216 }
1217
1218 /*
1219  * Allocate user-space memory for the duration of a single system call,
1220  * in order to marshall parameters inside a compat thunk.
1221  */
1222 void __user *compat_alloc_user_space(unsigned long len)
1223 {
1224         void __user *ptr;
1225
1226         /* If len would occupy more than half of the entire compat space... */
1227         if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1228                 return NULL;
1229
1230         ptr = arch_compat_alloc_user_space(len);
1231
1232         if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1233                 return NULL;
1234
1235         return ptr;
1236 }
1237 EXPORT_SYMBOL_GPL(compat_alloc_user_space);