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 <linux/uaccess.h>
  32
  33 static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
  34 {
  35         memset(txc, 0, sizeof(struct timex));
  36
  37         if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
  38                         __get_user(txc->modes, &utp->modes) ||
  39                         __get_user(txc->offset, &utp->offset) ||
  40                         __get_user(txc->freq, &utp->freq) ||
  41                         __get_user(txc->maxerror, &utp->maxerror) ||
  42                         __get_user(txc->esterror, &utp->esterror) ||
  43                         __get_user(txc->status, &utp->status) ||
  44                         __get_user(txc->constant, &utp->constant) ||
  45                         __get_user(txc->precision, &utp->precision) ||
  46                         __get_user(txc->tolerance, &utp->tolerance) ||
  47                         __get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
  48                         __get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
  49                         __get_user(txc->tick, &utp->tick) ||
  50                         __get_user(txc->ppsfreq, &utp->ppsfreq) ||
  51                         __get_user(txc->jitter, &utp->jitter) ||
  52                         __get_user(txc->shift, &utp->shift) ||
  53                         __get_user(txc->stabil, &utp->stabil) ||
  54                         __get_user(txc->jitcnt, &utp->jitcnt) ||
  55                         __get_user(txc->calcnt, &utp->calcnt) ||
  56                         __get_user(txc->errcnt, &utp->errcnt) ||
  57                         __get_user(txc->stbcnt, &utp->stbcnt))
  58                 return -EFAULT;
  59
  60         return 0;
  61 }
  62
  63 static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
  64 {
  65         if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
  66                         __put_user(txc->modes, &utp->modes) ||
  67                         __put_user(txc->offset, &utp->offset) ||
  68                         __put_user(txc->freq, &utp->freq) ||
  69                         __put_user(txc->maxerror, &utp->maxerror) ||
  70                         __put_user(txc->esterror, &utp->esterror) ||
  71                         __put_user(txc->status, &utp->status) ||
  72                         __put_user(txc->constant, &utp->constant) ||
  73                         __put_user(txc->precision, &utp->precision) ||
  74                         __put_user(txc->tolerance, &utp->tolerance) ||
  75                         __put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
  76                         __put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
  77                         __put_user(txc->tick, &utp->tick) ||
  78                         __put_user(txc->ppsfreq, &utp->ppsfreq) ||
  79                         __put_user(txc->jitter, &utp->jitter) ||
  80                         __put_user(txc->shift, &utp->shift) ||
  81                         __put_user(txc->stabil, &utp->stabil) ||
  82                         __put_user(txc->jitcnt, &utp->jitcnt) ||
  83                         __put_user(txc->calcnt, &utp->calcnt) ||
  84                         __put_user(txc->errcnt, &utp->errcnt) ||
  85                         __put_user(txc->stbcnt, &utp->stbcnt) ||
  86                         __put_user(txc->tai, &utp->tai))
  87                 return -EFAULT;
  88         return 0;
  89 }
  90
  91 COMPAT_SYSCALL_DEFINE2(gettimeofday, struct compat_timeval __user *, tv,
  92                        struct timezone __user *, tz)
  93 {
  94         if (tv) {
  95                 struct timeval ktv;
  96                 do_gettimeofday(&ktv);
  97                 if (compat_put_timeval(&ktv, tv))
  98                         return -EFAULT;
  99         }
 100         if (tz) {
 101                 if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
 102                         return -EFAULT;
 103         }
 104
 105         return 0;
 106 }
 107
 108 COMPAT_SYSCALL_DEFINE2(settimeofday, struct compat_timeval __user *, tv,
 109                        struct timezone __user *, tz)
 110 {
 111         struct timeval user_tv;
 112         struct timespec new_ts;
 113         struct timezone new_tz;
 114
 115         if (tv) {
 116                 if (compat_get_timeval(&user_tv, tv))
 117                         return -EFAULT;
 118                 new_ts.tv_sec = user_tv.tv_sec;
 119                 new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
 120         }
 121         if (tz) {
 122                 if (copy_from_user(&new_tz, tz, sizeof(*tz)))
 123                         return -EFAULT;
 124         }
 125
 126         return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
 127 }
 128
 129 static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
 130 {
 131         return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
 132                         __get_user(tv->tv_sec, &ctv->tv_sec) ||
 133                         __get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 134 }
 135
 136 static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
 137 {
 138         return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
 139                         __put_user(tv->tv_sec, &ctv->tv_sec) ||
 140                         __put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
 141 }
 142
 143 static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
 144 {
 145         return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
 146                         __get_user(ts->tv_sec, &cts->tv_sec) ||
 147                         __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 148 }
 149
 150 static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
 151 {
 152         return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
 153                         __put_user(ts->tv_sec, &cts->tv_sec) ||
 154                         __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
 155 }
 156
 157 int compat_get_timeval(struct timeval *tv, const void __user *utv)
 158 {
 159         if (COMPAT_USE_64BIT_TIME)
 160                 return copy_from_user(tv, utv, sizeof(*tv)) ? -EFAULT : 0;
 161         else
 162                 return __compat_get_timeval(tv, utv);
 163 }
 164 EXPORT_SYMBOL_GPL(compat_get_timeval);
 165
 166 int compat_put_timeval(const struct timeval *tv, void __user *utv)
 167 {
 168         if (COMPAT_USE_64BIT_TIME)
 169                 return copy_to_user(utv, tv, sizeof(*tv)) ? -EFAULT : 0;
 170         else
 171                 return __compat_put_timeval(tv, utv);
 172 }
 173 EXPORT_SYMBOL_GPL(compat_put_timeval);
 174
 175 int compat_get_timespec(struct timespec *ts, const void __user *uts)
 176 {
 177         if (COMPAT_USE_64BIT_TIME)
 178                 return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0;
 179         else
 180                 return __compat_get_timespec(ts, uts);
 181 }
 182 EXPORT_SYMBOL_GPL(compat_get_timespec);
 183
 184 int compat_put_timespec(const struct timespec *ts, void __user *uts)
 185 {
 186         if (COMPAT_USE_64BIT_TIME)
 187                 return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0;
 188         else
 189                 return __compat_put_timespec(ts, uts);
 190 }
 191 EXPORT_SYMBOL_GPL(compat_put_timespec);
 192
 193 int compat_convert_timespec(struct timespec __user **kts,
 194                             const void __user *cts)
 195 {
 196         struct timespec ts;
 197         struct timespec __user *uts;
 198
 199         if (!cts || COMPAT_USE_64BIT_TIME) {
 200                 *kts = (struct timespec __user *)cts;
 201                 return 0;
 202         }
 203
 204         uts = compat_alloc_user_space(sizeof(ts));
 205         if (!uts)
 206                 return -EFAULT;
 207         if (compat_get_timespec(&ts, cts))
 208                 return -EFAULT;
 209         if (copy_to_user(uts, &ts, sizeof(ts)))
 210                 return -EFAULT;
 211
 212         *kts = uts;
 213         return 0;
 214 }
 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 == -ERESTART_RESTARTBLOCK) {
 230                 rmtp = restart->nanosleep.compat_rmtp;
 231
 232                 if (rmtp && compat_put_timespec(&rmt, rmtp))
 233                         return -EFAULT;
 234         }
 235
 236         return ret;
 237 }
 238
 239 COMPAT_SYSCALL_DEFINE2(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 (compat_get_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         /*
 260          * hrtimer_nanosleep() can only return 0 or
 261          * -ERESTART_RESTARTBLOCK here because:
 262          *
 263          * - we call it with HRTIMER_MODE_REL and therefor exclude the
 264          *   -ERESTARTNOHAND return path.
 265          *
 266          * - we supply the rmtp argument from the task stack (due to
 267          *   the necessary compat conversion. So the update cannot
 268          *   fail, which excludes the -EFAULT return path as well. If
 269          *   it fails nevertheless we have a bigger problem and wont
 270          *   reach this place anymore.
 271          *
 272          * - if the return value is 0, we do not have to update rmtp
 273          *    because there is no remaining time.
 274          *
 275          * We check for -ERESTART_RESTARTBLOCK nevertheless if the
 276          * core implementation decides to return random nonsense.
 277          */
 278         if (ret == -ERESTART_RESTARTBLOCK) {
 279                 struct restart_block *restart = &current->restart_block;
 280
 281                 restart->fn = compat_nanosleep_restart;
 282                 restart->nanosleep.compat_rmtp = rmtp;
 283
 284                 if (rmtp && compat_put_timespec(&rmt, rmtp))
 285                         return -EFAULT;
 286         }
 287         return ret;
 288 }
 289
 290 static inline long get_compat_itimerval(struct itimerval *o,
 291                 struct compat_itimerval __user *i)
 292 {
 293         return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
 294                 (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
 295                  __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
 296                  __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
 297                  __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
 298 }
 299
 300 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
 301                 struct itimerval *i)
 302 {
 303         return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
 304                 (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
 305                  __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
 306                  __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
 307                  __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
 308 }
 309
 310 asmlinkage long sys_ni_posix_timers(void);
 311
 312 COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
 313                 struct compat_itimerval __user *, it)
 314 {
 315         struct itimerval kit;
 316         int error;
 317
 318         if (!IS_ENABLED(CONFIG_POSIX_TIMERS))
 319                 return sys_ni_posix_timers();
 320
 321         error = do_getitimer(which, &kit);
 322         if (!error && put_compat_itimerval(it, &kit))
 323                 error = -EFAULT;
 324         return error;
 325 }
 326
 327 COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
 328                 struct compat_itimerval __user *, in,
 329                 struct compat_itimerval __user *, out)
 330 {
 331         struct itimerval kin, kout;
 332         int error;
 333
 334         if (!IS_ENABLED(CONFIG_POSIX_TIMERS))
 335                 return sys_ni_posix_timers();
 336
 337         if (in) {
 338                 if (get_compat_itimerval(&kin, in))
 339                         return -EFAULT;
 340         } else
 341                 memset(&kin, 0, sizeof(kin));
 342
 343         error = do_setitimer(which, &kin, out ? &kout : NULL);
 344         if (error || !out)
 345                 return error;
 346         if (put_compat_itimerval(out, &kout))
 347                 return -EFAULT;
 348         return 0;
 349 }
 350
 351 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
 352 {
 353         return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
 354 }
 355
 356 COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
 357 {
 358         if (tbuf) {
 359                 struct tms tms;
 360                 struct compat_tms tmp;
 361
 362                 do_sys_times(&tms);
 363                 /* Convert our struct tms to the compat version. */
 364                 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
 365                 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
 366                 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
 367                 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
 368                 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
 369                         return -EFAULT;
 370         }
 371         force_successful_syscall_return();
 372         return compat_jiffies_to_clock_t(jiffies);
 373 }
 374
 375 #ifdef __ARCH_WANT_SYS_SIGPENDING
 376
 377 /*
 378  * Assumption: old_sigset_t and compat_old_sigset_t are both
 379  * types that can be passed to put_user()/get_user().
 380  */
 381
 382 COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
 383 {
 384         old_sigset_t s;
 385         long ret;
 386         mm_segment_t old_fs = get_fs();
 387
 388         set_fs(KERNEL_DS);
 389         ret = sys_sigpending((old_sigset_t __user *) &s);
 390         set_fs(old_fs);
 391         if (ret == 0)
 392                 ret = put_user(s, set);
 393         return ret;
 394 }
 395
 396 #endif
 397
 398 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
 399
 400 /*
 401  * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
 402  * blocked set of signals to the supplied signal set
 403  */
 404 static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
 405 {
 406         memcpy(blocked->sig, &set, sizeof(set));
 407 }
 408
 409 COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
 410                        compat_old_sigset_t __user *, nset,
 411                        compat_old_sigset_t __user *, oset)
 412 {
 413         old_sigset_t old_set, new_set;
 414         sigset_t new_blocked;
 415
 416         old_set = current->blocked.sig[0];
 417
 418         if (nset) {
 419                 if (get_user(new_set, nset))
 420                         return -EFAULT;
 421                 new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
 422
 423                 new_blocked = current->blocked;
 424
 425                 switch (how) {
 426                 case SIG_BLOCK:
 427                         sigaddsetmask(&new_blocked, new_set);
 428                         break;
 429                 case SIG_UNBLOCK:
 430                         sigdelsetmask(&new_blocked, new_set);
 431                         break;
 432                 case SIG_SETMASK:
 433                         compat_sig_setmask(&new_blocked, new_set);
 434                         break;
 435                 default:
 436                         return -EINVAL;
 437                 }
 438
 439                 set_current_blocked(&new_blocked);
 440         }
 441
 442         if (oset) {
 443                 if (put_user(old_set, oset))
 444                         return -EFAULT;
 445         }
 446
 447         return 0;
 448 }
 449
 450 #endif
 451
 452 COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
 453                        struct compat_rlimit __user *, rlim)
 454 {
 455         struct rlimit r;
 456
 457         if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
 458             __get_user(r.rlim_cur, &rlim->rlim_cur) ||
 459             __get_user(r.rlim_max, &rlim->rlim_max))
 460                 return -EFAULT;
 461
 462         if (r.rlim_cur == COMPAT_RLIM_INFINITY)
 463                 r.rlim_cur = RLIM_INFINITY;
 464         if (r.rlim_max == COMPAT_RLIM_INFINITY)
 465                 r.rlim_max = RLIM_INFINITY;
 466         return do_prlimit(current, resource, &r, NULL);
 467 }
 468
 469 #ifdef COMPAT_RLIM_OLD_INFINITY
 470
 471 COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
 472                        struct compat_rlimit __user *, rlim)
 473 {
 474         struct rlimit r;
 475         int ret;
 476         mm_segment_t old_fs = get_fs();
 477
 478         set_fs(KERNEL_DS);
 479         ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r);
 480         set_fs(old_fs);
 481
 482         if (!ret) {
 483                 if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
 484                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 485                 if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
 486                         r.rlim_max = COMPAT_RLIM_INFINITY;
 487
 488                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 489                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 490                     __put_user(r.rlim_max, &rlim->rlim_max))
 491                         return -EFAULT;
 492         }
 493         return ret;
 494 }
 495
 496 #endif
 497
 498 COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
 499                        struct compat_rlimit __user *, rlim)
 500 {
 501         struct rlimit r;
 502         int ret;
 503
 504         ret = do_prlimit(current, resource, NULL, &r);
 505         if (!ret) {
 506                 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
 507                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 508                 if (r.rlim_max > COMPAT_RLIM_INFINITY)
 509                         r.rlim_max = COMPAT_RLIM_INFINITY;
 510
 511                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 512                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 513                     __put_user(r.rlim_max, &rlim->rlim_max))
 514                         return -EFAULT;
 515         }
 516         return ret;
 517 }
 518
 519 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 520 {
 521         if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
 522             __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
 523             __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
 524             __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
 525             __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
 526             __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
 527             __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
 528             __put_user(r->ru_idrss, &ru->ru_idrss) ||
 529             __put_user(r->ru_isrss, &ru->ru_isrss) ||
 530             __put_user(r->ru_minflt, &ru->ru_minflt) ||
 531             __put_user(r->ru_majflt, &ru->ru_majflt) ||
 532             __put_user(r->ru_nswap, &ru->ru_nswap) ||
 533             __put_user(r->ru_inblock, &ru->ru_inblock) ||
 534             __put_user(r->ru_oublock, &ru->ru_oublock) ||
 535             __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
 536             __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
 537             __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
 538             __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
 539             __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
 540                 return -EFAULT;
 541         return 0;
 542 }
 543
 544 COMPAT_SYSCALL_DEFINE4(wait4,
 545         compat_pid_t, pid,
 546         compat_uint_t __user *, stat_addr,
 547         int, options,
 548         struct compat_rusage __user *, ru)
 549 {
 550         if (!ru) {
 551                 return sys_wait4(pid, stat_addr, options, NULL);
 552         } else {
 553                 struct rusage r;
 554                 int ret;
 555                 unsigned int status;
 556                 mm_segment_t old_fs = get_fs();
 557
 558                 set_fs (KERNEL_DS);
 559                 ret = sys_wait4(pid,
 560                                 (stat_addr ?
 561                                  (unsigned int __user *) &status : NULL),
 562                                 options, (struct rusage __user *) &r);
 563                 set_fs (old_fs);
 564
 565                 if (ret > 0) {
 566                         if (put_compat_rusage(&r, ru))
 567                                 return -EFAULT;
 568                         if (stat_addr && put_user(status, stat_addr))
 569                                 return -EFAULT;
 570                 }
 571                 return ret;
 572         }
 573 }
 574
 575 COMPAT_SYSCALL_DEFINE5(waitid,
 576                 int, which, compat_pid_t, pid,
 577                 struct compat_siginfo __user *, uinfo, int, options,
 578                 struct compat_rusage __user *, uru)
 579 {
 580         siginfo_t info;
 581         struct rusage ru;
 582         long ret;
 583         mm_segment_t old_fs = get_fs();
 584
 585         memset(&info, 0, sizeof(info));
 586
 587         set_fs(KERNEL_DS);
 588         ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 589                          uru ? (struct rusage __user *)&ru : NULL);
 590         set_fs(old_fs);
 591
 592         if ((ret < 0) || (info.si_signo == 0))
 593                 return ret;
 594
 595         if (uru) {
 596                 /* sys_waitid() overwrites everything in ru */
 597                 if (COMPAT_USE_64BIT_TIME)
 598                         ret = copy_to_user(uru, &ru, sizeof(ru));
 599                 else
 600                         ret = put_compat_rusage(&ru, uru);
 601                 if (ret)
 602                         return -EFAULT;
 603         }
 604
 605         BUG_ON(info.si_code & __SI_MASK);
 606         info.si_code |= __SI_CHLD;
 607         return copy_siginfo_to_user32(uinfo, &info);
 608 }
 609
 610 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 611                                     unsigned len, struct cpumask *new_mask)
 612 {
 613         unsigned long *k;
 614
 615         if (len < cpumask_size())
 616                 memset(new_mask, 0, cpumask_size());
 617         else if (len > cpumask_size())
 618                 len = cpumask_size();
 619
 620         k = cpumask_bits(new_mask);
 621         return compat_get_bitmap(k, user_mask_ptr, len * 8);
 622 }
 623
 624 COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid,
 625                        unsigned int, len,
 626                        compat_ulong_t __user *, user_mask_ptr)
 627 {
 628         cpumask_var_t new_mask;
 629         int retval;
 630
 631         if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
 632                 return -ENOMEM;
 633
 634         retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
 635         if (retval)
 636                 goto out;
 637
 638         retval = sched_setaffinity(pid, new_mask);
 639 out:
 640         free_cpumask_var(new_mask);
 641         return retval;
 642 }
 643
 644 COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t,  pid, unsigned int, len,
 645                        compat_ulong_t __user *, user_mask_ptr)
 646 {
 647         int ret;
 648         cpumask_var_t mask;
 649
 650         if ((len * BITS_PER_BYTE) < nr_cpu_ids)
 651                 return -EINVAL;
 652         if (len & (sizeof(compat_ulong_t)-1))
 653                 return -EINVAL;
 654
 655         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 656                 return -ENOMEM;
 657
 658         ret = sched_getaffinity(pid, mask);
 659         if (ret == 0) {
 660                 size_t retlen = min_t(size_t, len, cpumask_size());
 661
 662                 if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
 663                         ret = -EFAULT;
 664                 else
 665                         ret = retlen;
 666         }
 667         free_cpumask_var(mask);
 668
 669         return ret;
 670 }
 671
 672 int get_compat_itimerspec(struct itimerspec *dst,
 673                           const struct compat_itimerspec __user *src)
 674 {
 675         if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
 676             __compat_get_timespec(&dst->it_value, &src->it_value))
 677                 return -EFAULT;
 678         return 0;
 679 }
 680
 681 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 682                           const struct itimerspec *src)
 683 {
 684         if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
 685             __compat_put_timespec(&src->it_value, &dst->it_value))
 686                 return -EFAULT;
 687         return 0;
 688 }
 689
 690 COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
 691                        struct compat_sigevent __user *, timer_event_spec,
 692                        timer_t __user *, created_timer_id)
 693 {
 694         struct sigevent __user *event = NULL;
 695
 696         if (timer_event_spec) {
 697                 struct sigevent kevent;
 698
 699                 event = compat_alloc_user_space(sizeof(*event));
 700                 if (get_compat_sigevent(&kevent, timer_event_spec) ||
 701                     copy_to_user(event, &kevent, sizeof(*event)))
 702                         return -EFAULT;
 703         }
 704
 705         return sys_timer_create(which_clock, event, created_timer_id);
 706 }
 707
 708 COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
 709                        struct compat_itimerspec __user *, new,
 710                        struct compat_itimerspec __user *, old)
 711 {
 712         long err;
 713         mm_segment_t oldfs;
 714         struct itimerspec newts, oldts;
 715
 716         if (!new)
 717                 return -EINVAL;
 718         if (get_compat_itimerspec(&newts, new))
 719                 return -EFAULT;
 720         oldfs = get_fs();
 721         set_fs(KERNEL_DS);
 722         err = sys_timer_settime(timer_id, flags,
 723                                 (struct itimerspec __user *) &newts,
 724                                 (struct itimerspec __user *) &oldts);
 725         set_fs(oldfs);
 726         if (!err && old && put_compat_itimerspec(old, &oldts))
 727                 return -EFAULT;
 728         return err;
 729 }
 730
 731 COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
 732                        struct compat_itimerspec __user *, setting)
 733 {
 734         long err;
 735         mm_segment_t oldfs;
 736         struct itimerspec ts;
 737
 738         oldfs = get_fs();
 739         set_fs(KERNEL_DS);
 740         err = sys_timer_gettime(timer_id,
 741                                 (struct itimerspec __user *) &ts);
 742         set_fs(oldfs);
 743         if (!err && put_compat_itimerspec(setting, &ts))
 744                 return -EFAULT;
 745         return err;
 746 }
 747
 748 COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
 749                        struct compat_timespec __user *, tp)
 750 {
 751         long err;
 752         mm_segment_t oldfs;
 753         struct timespec ts;
 754
 755         if (compat_get_timespec(&ts, tp))
 756                 return -EFAULT;
 757         oldfs = get_fs();
 758         set_fs(KERNEL_DS);
 759         err = sys_clock_settime(which_clock,
 760                                 (struct timespec __user *) &ts);
 761         set_fs(oldfs);
 762         return err;
 763 }
 764
 765 COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
 766                        struct compat_timespec __user *, tp)
 767 {
 768         long err;
 769         mm_segment_t oldfs;
 770         struct timespec ts;
 771
 772         oldfs = get_fs();
 773         set_fs(KERNEL_DS);
 774         err = sys_clock_gettime(which_clock,
 775                                 (struct timespec __user *) &ts);
 776         set_fs(oldfs);
 777         if (!err && compat_put_timespec(&ts, tp))
 778                 return -EFAULT;
 779         return err;
 780 }
 781
 782 COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
 783                        struct compat_timex __user *, utp)
 784 {
 785         struct timex txc;
 786         mm_segment_t oldfs;
 787         int err, ret;
 788
 789         err = compat_get_timex(&txc, utp);
 790         if (err)
 791                 return err;
 792
 793         oldfs = get_fs();
 794         set_fs(KERNEL_DS);
 795         ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
 796         set_fs(oldfs);
 797
 798         err = compat_put_timex(utp, &txc);
 799         if (err)
 800                 return err;
 801
 802         return ret;
 803 }
 804
 805 COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
 806                        struct compat_timespec __user *, tp)
 807 {
 808         long err;
 809         mm_segment_t oldfs;
 810         struct timespec ts;
 811
 812         oldfs = get_fs();
 813         set_fs(KERNEL_DS);
 814         err = sys_clock_getres(which_clock,
 815                                (struct timespec __user *) &ts);
 816         set_fs(oldfs);
 817         if (!err && tp && compat_put_timespec(&ts, tp))
 818                 return -EFAULT;
 819         return err;
 820 }
 821
 822 static long compat_clock_nanosleep_restart(struct restart_block *restart)
 823 {
 824         long err;
 825         mm_segment_t oldfs;
 826         struct timespec tu;
 827         struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp;
 828
 829         restart->nanosleep.rmtp = (struct timespec __user *) &tu;
 830         oldfs = get_fs();
 831         set_fs(KERNEL_DS);
 832         err = clock_nanosleep_restart(restart);
 833         set_fs(oldfs);
 834
 835         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 836             compat_put_timespec(&tu, rmtp))
 837                 return -EFAULT;
 838
 839         if (err == -ERESTART_RESTARTBLOCK) {
 840                 restart->fn = compat_clock_nanosleep_restart;
 841                 restart->nanosleep.compat_rmtp = rmtp;
 842         }
 843         return err;
 844 }
 845
 846 COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
 847                        struct compat_timespec __user *, rqtp,
 848                        struct compat_timespec __user *, rmtp)
 849 {
 850         long err;
 851         mm_segment_t oldfs;
 852         struct timespec in, out;
 853         struct restart_block *restart;
 854
 855         if (compat_get_timespec(&in, rqtp))
 856                 return -EFAULT;
 857
 858         oldfs = get_fs();
 859         set_fs(KERNEL_DS);
 860         err = sys_clock_nanosleep(which_clock, flags,
 861                                   (struct timespec __user *) &in,
 862                                   (struct timespec __user *) &out);
 863         set_fs(oldfs);
 864
 865         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 866             compat_put_timespec(&out, rmtp))
 867                 return -EFAULT;
 868
 869         if (err == -ERESTART_RESTARTBLOCK) {
 870                 restart = &current->restart_block;
 871                 restart->fn = compat_clock_nanosleep_restart;
 872                 restart->nanosleep.compat_rmtp = rmtp;
 873         }
 874         return err;
 875 }
 876
 877 /*
 878  * We currently only need the following fields from the sigevent
 879  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 880  * sigev_notify_thread_id).  The others are handled in user mode.
 881  * We also assume that copying sigev_value.sival_int is sufficient
 882  * to keep all the bits of sigev_value.sival_ptr intact.
 883  */
 884 int get_compat_sigevent(struct sigevent *event,
 885                 const struct compat_sigevent __user *u_event)
 886 {
 887         memset(event, 0, sizeof(*event));
 888         return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 889                 __get_user(event->sigev_value.sival_int,
 890                         &u_event->sigev_value.sival_int) ||
 891                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
 892                 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
 893                 __get_user(event->sigev_notify_thread_id,
 894                         &u_event->sigev_notify_thread_id))
 895                 ? -EFAULT : 0;
 896 }
 897
 898 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 899                        unsigned long bitmap_size)
 900 {
 901         int i, j;
 902         unsigned long m;
 903         compat_ulong_t um;
 904         unsigned long nr_compat_longs;
 905
 906         /* align bitmap up to nearest compat_long_t boundary */
 907         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 908
 909         if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 910                 return -EFAULT;
 911
 912         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 913
 914         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 915                 m = 0;
 916
 917                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 918                         /*
 919                          * We dont want to read past the end of the userspace
 920                          * bitmap. We must however ensure the end of the
 921                          * kernel bitmap is zeroed.
 922                          */
 923                         if (nr_compat_longs) {
 924                                 nr_compat_longs--;
 925                                 if (__get_user(um, umask))
 926                                         return -EFAULT;
 927                         } else {
 928                                 um = 0;
 929                         }
 930
 931                         umask++;
 932                         m |= (long)um << (j * BITS_PER_COMPAT_LONG);
 933                 }
 934                 *mask++ = m;
 935         }
 936
 937         return 0;
 938 }
 939
 940 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 941                        unsigned long bitmap_size)
 942 {
 943         int i, j;
 944         unsigned long m;
 945         compat_ulong_t um;
 946         unsigned long nr_compat_longs;
 947
 948         /* align bitmap up to nearest compat_long_t boundary */
 949         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 950
 951         if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 952                 return -EFAULT;
 953
 954         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 955
 956         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 957                 m = *mask++;
 958
 959                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 960                         um = m;
 961
 962                         /*
 963                          * We dont want to write past the end of the userspace
 964                          * bitmap.
 965                          */
 966                         if (nr_compat_longs) {
 967                                 nr_compat_longs--;
 968                                 if (__put_user(um, umask))
 969                                         return -EFAULT;
 970                         }
 971
 972                         umask++;
 973                         m >>= 4*sizeof(um);
 974                         m >>= 4*sizeof(um);
 975                 }
 976         }
 977
 978         return 0;
 979 }
 980
 981 void
 982 sigset_from_compat(sigset_t *set, const compat_sigset_t *compat)
 983 {
 984         switch (_NSIG_WORDS) {
 985         case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
 986         case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
 987         case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
 988         case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
 989         }
 990 }
 991 EXPORT_SYMBOL_GPL(sigset_from_compat);
 992
 993 void
 994 sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
 995 {
 996         switch (_NSIG_WORDS) {
 997         case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
 998         case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
 999         case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
1000         case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
1001         }
1002 }
1003
1004 COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
1005                 struct compat_siginfo __user *, uinfo,
1006                 struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
1007 {
1008         compat_sigset_t s32;
1009         sigset_t s;
1010         struct timespec t;
1011         siginfo_t info;
1012         long ret;
1013
1014         if (sigsetsize != sizeof(sigset_t))
1015                 return -EINVAL;
1016
1017         if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
1018                 return -EFAULT;
1019         sigset_from_compat(&s, &s32);
1020
1021         if (uts) {
1022                 if (compat_get_timespec(&t, uts))
1023                         return -EFAULT;
1024         }
1025
1026         ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1027
1028         if (ret > 0 && uinfo) {
1029                 if (copy_siginfo_to_user32(uinfo, &info))
1030                         ret = -EFAULT;
1031         }
1032
1033         return ret;
1034 }
1035
1036 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1037
1038 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1039
1040 COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
1041 {
1042         compat_time_t i;
1043         struct timeval tv;
1044
1045         do_gettimeofday(&tv);
1046         i = tv.tv_sec;
1047
1048         if (tloc) {
1049                 if (put_user(i,tloc))
1050                         return -EFAULT;
1051         }
1052         force_successful_syscall_return();
1053         return i;
1054 }
1055
1056 COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
1057 {
1058         struct timespec tv;
1059         int err;
1060
1061         if (get_user(tv.tv_sec, tptr))
1062                 return -EFAULT;
1063
1064         tv.tv_nsec = 0;
1065
1066         err = security_settime(&tv, NULL);
1067         if (err)
1068                 return err;
1069
1070         do_settimeofday(&tv);
1071         return 0;
1072 }
1073
1074 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1075
1076 COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)
1077 {
1078         struct timex txc;
1079         int err, ret;
1080
1081         err = compat_get_timex(&txc, utp);
1082         if (err)
1083                 return err;
1084
1085         ret = do_adjtimex(&txc);
1086
1087         err = compat_put_timex(utp, &txc);
1088         if (err)
1089                 return err;
1090
1091         return ret;
1092 }
1093
1094 #ifdef CONFIG_NUMA
1095 COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
1096                        compat_uptr_t __user *, pages32,
1097                        const int __user *, nodes,
1098                        int __user *, status,
1099                        int, flags)
1100 {
1101         const void __user * __user *pages;
1102         int i;
1103
1104         pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1105         for (i = 0; i < nr_pages; i++) {
1106                 compat_uptr_t p;
1107
1108                 if (get_user(p, pages32 + i) ||
1109                         put_user(compat_ptr(p), pages + i))
1110                         return -EFAULT;
1111         }
1112         return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1113 }
1114
1115 COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
1116                        compat_ulong_t, maxnode,
1117                        const compat_ulong_t __user *, old_nodes,
1118                        const compat_ulong_t __user *, new_nodes)
1119 {
1120         unsigned long __user *old = NULL;
1121         unsigned long __user *new = NULL;
1122         nodemask_t tmp_mask;
1123         unsigned long nr_bits;
1124         unsigned long size;
1125
1126         nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1127         size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1128         if (old_nodes) {
1129                 if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1130                         return -EFAULT;
1131                 old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1132                 if (new_nodes)
1133                         new = old + size / sizeof(unsigned long);
1134                 if (copy_to_user(old, nodes_addr(tmp_mask), size))
1135                         return -EFAULT;
1136         }
1137         if (new_nodes) {
1138                 if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1139                         return -EFAULT;
1140                 if (new == NULL)
1141                         new = compat_alloc_user_space(size);
1142                 if (copy_to_user(new, nodes_addr(tmp_mask), size))
1143                         return -EFAULT;
1144         }
1145         return sys_migrate_pages(pid, nr_bits + 1, old, new);
1146 }
1147 #endif
1148
1149 COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1150                        compat_pid_t, pid,
1151                        struct compat_timespec __user *, interval)
1152 {
1153         struct timespec t;
1154         int ret;
1155         mm_segment_t old_fs = get_fs();
1156
1157         set_fs(KERNEL_DS);
1158         ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1159         set_fs(old_fs);
1160         if (compat_put_timespec(&t, interval))
1161                 return -EFAULT;
1162         return ret;
1163 }
1164
1165 /*
1166  * Allocate user-space memory for the duration of a single system call,
1167  * in order to marshall parameters inside a compat thunk.
1168  */
1169 void __user *compat_alloc_user_space(unsigned long len)
1170 {
1171         void __user *ptr;
1172
1173         /* If len would occupy more than half of the entire compat space... */
1174         if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1175                 return NULL;
1176
1177         ptr = arch_compat_alloc_user_space(len);
1178
1179         if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1180                 return NULL;
1181
1182         return ptr;
1183 }
1184 EXPORT_SYMBOL_GPL(compat_alloc_user_space);