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