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 COMPAT_SYSCALL_DEFINE2(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 COMPAT_SYSCALL_DEFINE3(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 COMPAT_SYSCALL_DEFINE3(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 COMPAT_SYSCALL_DEFINE4(wait4,
 520         compat_pid_t, pid,
 521         compat_uint_t __user *, stat_addr,
 522         int, options,
 523         struct compat_rusage __user *, ru)
 524 {
 525         if (!ru) {
 526                 return sys_wait4(pid, stat_addr, options, NULL);
 527         } else {
 528                 struct rusage r;
 529                 int ret;
 530                 unsigned int status;
 531                 mm_segment_t old_fs = get_fs();
 532
 533                 set_fs (KERNEL_DS);
 534                 ret = sys_wait4(pid,
 535                                 (stat_addr ?
 536                                  (unsigned int __user *) &status : NULL),
 537                                 options, (struct rusage __user *) &r);
 538                 set_fs (old_fs);
 539
 540                 if (ret > 0) {
 541                         if (put_compat_rusage(&r, ru))
 542                                 return -EFAULT;
 543                         if (stat_addr && put_user(status, stat_addr))
 544                                 return -EFAULT;
 545                 }
 546                 return ret;
 547         }
 548 }
 549
 550 COMPAT_SYSCALL_DEFINE5(waitid,
 551                 int, which, compat_pid_t, pid,
 552                 struct compat_siginfo __user *, uinfo, int, options,
 553                 struct compat_rusage __user *, uru)
 554 {
 555         siginfo_t info;
 556         struct rusage ru;
 557         long ret;
 558         mm_segment_t old_fs = get_fs();
 559
 560         memset(&info, 0, sizeof(info));
 561
 562         set_fs(KERNEL_DS);
 563         ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 564                          uru ? (struct rusage __user *)&ru : NULL);
 565         set_fs(old_fs);
 566
 567         if ((ret < 0) || (info.si_signo == 0))
 568                 return ret;
 569
 570         if (uru) {
 571                 /* sys_waitid() overwrites everything in ru */
 572                 if (COMPAT_USE_64BIT_TIME)
 573                         ret = copy_to_user(uru, &ru, sizeof(ru));
 574                 else
 575                         ret = put_compat_rusage(&ru, uru);
 576                 if (ret)
 577                         return -EFAULT;
 578         }
 579
 580         BUG_ON(info.si_code & __SI_MASK);
 581         info.si_code |= __SI_CHLD;
 582         return copy_siginfo_to_user32(uinfo, &info);
 583 }
 584
 585 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 586                                     unsigned len, struct cpumask *new_mask)
 587 {
 588         unsigned long *k;
 589
 590         if (len < cpumask_size())
 591                 memset(new_mask, 0, cpumask_size());
 592         else if (len > cpumask_size())
 593                 len = cpumask_size();
 594
 595         k = cpumask_bits(new_mask);
 596         return compat_get_bitmap(k, user_mask_ptr, len * 8);
 597 }
 598
 599 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
 600                                              unsigned int len,
 601                                              compat_ulong_t __user *user_mask_ptr)
 602 {
 603         cpumask_var_t new_mask;
 604         int retval;
 605
 606         if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
 607                 return -ENOMEM;
 608
 609         retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
 610         if (retval)
 611                 goto out;
 612
 613         retval = sched_setaffinity(pid, new_mask);
 614 out:
 615         free_cpumask_var(new_mask);
 616         return retval;
 617 }
 618
 619 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 620                                              compat_ulong_t __user *user_mask_ptr)
 621 {
 622         int ret;
 623         cpumask_var_t mask;
 624
 625         if ((len * BITS_PER_BYTE) < nr_cpu_ids)
 626                 return -EINVAL;
 627         if (len & (sizeof(compat_ulong_t)-1))
 628                 return -EINVAL;
 629
 630         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 631                 return -ENOMEM;
 632
 633         ret = sched_getaffinity(pid, mask);
 634         if (ret == 0) {
 635                 size_t retlen = min_t(size_t, len, cpumask_size());
 636
 637                 if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
 638                         ret = -EFAULT;
 639                 else
 640                         ret = retlen;
 641         }
 642         free_cpumask_var(mask);
 643
 644         return ret;
 645 }
 646
 647 int get_compat_itimerspec(struct itimerspec *dst,
 648                           const struct compat_itimerspec __user *src)
 649 {
 650         if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
 651             get_compat_timespec(&dst->it_value, &src->it_value))
 652                 return -EFAULT;
 653         return 0;
 654 }
 655
 656 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 657                           const struct itimerspec *src)
 658 {
 659         if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
 660             put_compat_timespec(&src->it_value, &dst->it_value))
 661                 return -EFAULT;
 662         return 0;
 663 }
 664
 665 long compat_sys_timer_create(clockid_t which_clock,
 666                         struct compat_sigevent __user *timer_event_spec,
 667                         timer_t __user *created_timer_id)
 668 {
 669         struct sigevent __user *event = NULL;
 670
 671         if (timer_event_spec) {
 672                 struct sigevent kevent;
 673
 674                 event = compat_alloc_user_space(sizeof(*event));
 675                 if (get_compat_sigevent(&kevent, timer_event_spec) ||
 676                     copy_to_user(event, &kevent, sizeof(*event)))
 677                         return -EFAULT;
 678         }
 679
 680         return sys_timer_create(which_clock, event, created_timer_id);
 681 }
 682
 683 long compat_sys_timer_settime(timer_t timer_id, int flags,
 684                           struct compat_itimerspec __user *new,
 685                           struct compat_itimerspec __user *old)
 686 {
 687         long err;
 688         mm_segment_t oldfs;
 689         struct itimerspec newts, oldts;
 690
 691         if (!new)
 692                 return -EINVAL;
 693         if (get_compat_itimerspec(&newts, new))
 694                 return -EFAULT;
 695         oldfs = get_fs();
 696         set_fs(KERNEL_DS);
 697         err = sys_timer_settime(timer_id, flags,
 698                                 (struct itimerspec __user *) &newts,
 699                                 (struct itimerspec __user *) &oldts);
 700         set_fs(oldfs);
 701         if (!err && old && put_compat_itimerspec(old, &oldts))
 702                 return -EFAULT;
 703         return err;
 704 }
 705
 706 long compat_sys_timer_gettime(timer_t timer_id,
 707                 struct compat_itimerspec __user *setting)
 708 {
 709         long err;
 710         mm_segment_t oldfs;
 711         struct itimerspec ts;
 712
 713         oldfs = get_fs();
 714         set_fs(KERNEL_DS);
 715         err = sys_timer_gettime(timer_id,
 716                                 (struct itimerspec __user *) &ts);
 717         set_fs(oldfs);
 718         if (!err && put_compat_itimerspec(setting, &ts))
 719                 return -EFAULT;
 720         return err;
 721 }
 722
 723 long compat_sys_clock_settime(clockid_t which_clock,
 724                 struct compat_timespec __user *tp)
 725 {
 726         long err;
 727         mm_segment_t oldfs;
 728         struct timespec ts;
 729
 730         if (get_compat_timespec(&ts, tp))
 731                 return -EFAULT;
 732         oldfs = get_fs();
 733         set_fs(KERNEL_DS);
 734         err = sys_clock_settime(which_clock,
 735                                 (struct timespec __user *) &ts);
 736         set_fs(oldfs);
 737         return err;
 738 }
 739
 740 long compat_sys_clock_gettime(clockid_t which_clock,
 741                 struct compat_timespec __user *tp)
 742 {
 743         long err;
 744         mm_segment_t oldfs;
 745         struct timespec ts;
 746
 747         oldfs = get_fs();
 748         set_fs(KERNEL_DS);
 749         err = sys_clock_gettime(which_clock,
 750                                 (struct timespec __user *) &ts);
 751         set_fs(oldfs);
 752         if (!err && put_compat_timespec(&ts, tp))
 753                 return -EFAULT;
 754         return err;
 755 }
 756
 757 long compat_sys_clock_adjtime(clockid_t which_clock,
 758                 struct compat_timex __user *utp)
 759 {
 760         struct timex txc;
 761         mm_segment_t oldfs;
 762         int err, ret;
 763
 764         err = compat_get_timex(&txc, utp);
 765         if (err)
 766                 return err;
 767
 768         oldfs = get_fs();
 769         set_fs(KERNEL_DS);
 770         ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
 771         set_fs(oldfs);
 772
 773         err = compat_put_timex(utp, &txc);
 774         if (err)
 775                 return err;
 776
 777         return ret;
 778 }
 779
 780 long compat_sys_clock_getres(clockid_t which_clock,
 781                 struct compat_timespec __user *tp)
 782 {
 783         long err;
 784         mm_segment_t oldfs;
 785         struct timespec ts;
 786
 787         oldfs = get_fs();
 788         set_fs(KERNEL_DS);
 789         err = sys_clock_getres(which_clock,
 790                                (struct timespec __user *) &ts);
 791         set_fs(oldfs);
 792         if (!err && tp && put_compat_timespec(&ts, tp))
 793                 return -EFAULT;
 794         return err;
 795 }
 796
 797 static long compat_clock_nanosleep_restart(struct restart_block *restart)
 798 {
 799         long err;
 800         mm_segment_t oldfs;
 801         struct timespec tu;
 802         struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
 803
 804         restart->nanosleep.rmtp = (struct timespec __user *) &tu;
 805         oldfs = get_fs();
 806         set_fs(KERNEL_DS);
 807         err = clock_nanosleep_restart(restart);
 808         set_fs(oldfs);
 809
 810         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 811             put_compat_timespec(&tu, rmtp))
 812                 return -EFAULT;
 813
 814         if (err == -ERESTART_RESTARTBLOCK) {
 815                 restart->fn = compat_clock_nanosleep_restart;
 816                 restart->nanosleep.compat_rmtp = rmtp;
 817         }
 818         return err;
 819 }
 820
 821 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
 822                             struct compat_timespec __user *rqtp,
 823                             struct compat_timespec __user *rmtp)
 824 {
 825         long err;
 826         mm_segment_t oldfs;
 827         struct timespec in, out;
 828         struct restart_block *restart;
 829
 830         if (get_compat_timespec(&in, rqtp))
 831                 return -EFAULT;
 832
 833         oldfs = get_fs();
 834         set_fs(KERNEL_DS);
 835         err = sys_clock_nanosleep(which_clock, flags,
 836                                   (struct timespec __user *) &in,
 837                                   (struct timespec __user *) &out);
 838         set_fs(oldfs);
 839
 840         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 841             put_compat_timespec(&out, rmtp))
 842                 return -EFAULT;
 843
 844         if (err == -ERESTART_RESTARTBLOCK) {
 845                 restart = &current_thread_info()->restart_block;
 846                 restart->fn = compat_clock_nanosleep_restart;
 847                 restart->nanosleep.compat_rmtp = rmtp;
 848         }
 849         return err;
 850 }
 851
 852 /*
 853  * We currently only need the following fields from the sigevent
 854  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 855  * sigev_notify_thread_id).  The others are handled in user mode.
 856  * We also assume that copying sigev_value.sival_int is sufficient
 857  * to keep all the bits of sigev_value.sival_ptr intact.
 858  */
 859 int get_compat_sigevent(struct sigevent *event,
 860                 const struct compat_sigevent __user *u_event)
 861 {
 862         memset(event, 0, sizeof(*event));
 863         return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 864                 __get_user(event->sigev_value.sival_int,
 865                         &u_event->sigev_value.sival_int) ||
 866                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
 867                 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
 868                 __get_user(event->sigev_notify_thread_id,
 869                         &u_event->sigev_notify_thread_id))
 870                 ? -EFAULT : 0;
 871 }
 872
 873 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 874                        unsigned long bitmap_size)
 875 {
 876         int i, j;
 877         unsigned long m;
 878         compat_ulong_t um;
 879         unsigned long nr_compat_longs;
 880
 881         /* align bitmap up to nearest compat_long_t boundary */
 882         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 883
 884         if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 885                 return -EFAULT;
 886
 887         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 888
 889         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 890                 m = 0;
 891
 892                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 893                         /*
 894                          * We dont want to read past the end of the userspace
 895                          * bitmap. We must however ensure the end of the
 896                          * kernel bitmap is zeroed.
 897                          */
 898                         if (nr_compat_longs-- > 0) {
 899                                 if (__get_user(um, umask))
 900                                         return -EFAULT;
 901                         } else {
 902                                 um = 0;
 903                         }
 904
 905                         umask++;
 906                         m |= (long)um << (j * BITS_PER_COMPAT_LONG);
 907                 }
 908                 *mask++ = m;
 909         }
 910
 911         return 0;
 912 }
 913
 914 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 915                        unsigned long bitmap_size)
 916 {
 917         int i, j;
 918         unsigned long m;
 919         compat_ulong_t um;
 920         unsigned long nr_compat_longs;
 921
 922         /* align bitmap up to nearest compat_long_t boundary */
 923         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 924
 925         if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 926                 return -EFAULT;
 927
 928         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 929
 930         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 931                 m = *mask++;
 932
 933                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 934                         um = m;
 935
 936                         /*
 937                          * We dont want to write past the end of the userspace
 938                          * bitmap.
 939                          */
 940                         if (nr_compat_longs-- > 0) {
 941                                 if (__put_user(um, umask))
 942                                         return -EFAULT;
 943                         }
 944
 945                         umask++;
 946                         m >>= 4*sizeof(um);
 947                         m >>= 4*sizeof(um);
 948                 }
 949         }
 950
 951         return 0;
 952 }
 953
 954 void
 955 sigset_from_compat(sigset_t *set, const compat_sigset_t *compat)
 956 {
 957         switch (_NSIG_WORDS) {
 958         case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
 959         case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
 960         case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
 961         case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
 962         }
 963 }
 964 EXPORT_SYMBOL_GPL(sigset_from_compat);
 965
 966 void
 967 sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
 968 {
 969         switch (_NSIG_WORDS) {
 970         case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
 971         case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
 972         case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
 973         case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
 974         }
 975 }
 976
 977 COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
 978                 struct compat_siginfo __user *, uinfo,
 979                 struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
 980 {
 981         compat_sigset_t s32;
 982         sigset_t s;
 983         struct timespec t;
 984         siginfo_t info;
 985         long ret;
 986
 987         if (sigsetsize != sizeof(sigset_t))
 988                 return -EINVAL;
 989
 990         if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
 991                 return -EFAULT;
 992         sigset_from_compat(&s, &s32);
 993
 994         if (uts) {
 995                 if (compat_get_timespec(&t, uts))
 996                         return -EFAULT;
 997         }
 998
 999         ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1000
1001         if (ret > 0 && uinfo) {
1002                 if (copy_siginfo_to_user32(uinfo, &info))
1003                         ret = -EFAULT;
1004         }
1005
1006         return ret;
1007 }
1008
1009 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1010
1011 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1012
1013 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
1014 {
1015         compat_time_t i;
1016         struct timeval tv;
1017
1018         do_gettimeofday(&tv);
1019         i = tv.tv_sec;
1020
1021         if (tloc) {
1022                 if (put_user(i,tloc))
1023                         return -EFAULT;
1024         }
1025         force_successful_syscall_return();
1026         return i;
1027 }
1028
1029 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
1030 {
1031         struct timespec tv;
1032         int err;
1033
1034         if (get_user(tv.tv_sec, tptr))
1035                 return -EFAULT;
1036
1037         tv.tv_nsec = 0;
1038
1039         err = security_settime(&tv, NULL);
1040         if (err)
1041                 return err;
1042
1043         do_settimeofday(&tv);
1044         return 0;
1045 }
1046
1047 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1048
1049 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
1050 {
1051         struct timex txc;
1052         int err, ret;
1053
1054         err = compat_get_timex(&txc, utp);
1055         if (err)
1056                 return err;
1057
1058         ret = do_adjtimex(&txc);
1059
1060         err = compat_put_timex(utp, &txc);
1061         if (err)
1062                 return err;
1063
1064         return ret;
1065 }
1066
1067 #ifdef CONFIG_NUMA
1068 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1069                 compat_uptr_t __user *pages32,
1070                 const int __user *nodes,
1071                 int __user *status,
1072                 int flags)
1073 {
1074         const void __user * __user *pages;
1075         int i;
1076
1077         pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1078         for (i = 0; i < nr_pages; i++) {
1079                 compat_uptr_t p;
1080
1081                 if (get_user(p, pages32 + i) ||
1082                         put_user(compat_ptr(p), pages + i))
1083                         return -EFAULT;
1084         }
1085         return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1086 }
1087
1088 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1089                         compat_ulong_t maxnode,
1090                         const compat_ulong_t __user *old_nodes,
1091                         const compat_ulong_t __user *new_nodes)
1092 {
1093         unsigned long __user *old = NULL;
1094         unsigned long __user *new = NULL;
1095         nodemask_t tmp_mask;
1096         unsigned long nr_bits;
1097         unsigned long size;
1098
1099         nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1100         size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1101         if (old_nodes) {
1102                 if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1103                         return -EFAULT;
1104                 old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1105                 if (new_nodes)
1106                         new = old + size / sizeof(unsigned long);
1107                 if (copy_to_user(old, nodes_addr(tmp_mask), size))
1108                         return -EFAULT;
1109         }
1110         if (new_nodes) {
1111                 if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1112                         return -EFAULT;
1113                 if (new == NULL)
1114                         new = compat_alloc_user_space(size);
1115                 if (copy_to_user(new, nodes_addr(tmp_mask), size))
1116                         return -EFAULT;
1117         }
1118         return sys_migrate_pages(pid, nr_bits + 1, old, new);
1119 }
1120 #endif
1121
1122 COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1123                        compat_pid_t, pid,
1124                        struct compat_timespec __user *, interval)
1125 {
1126         struct timespec t;
1127         int ret;
1128         mm_segment_t old_fs = get_fs();
1129
1130         set_fs(KERNEL_DS);
1131         ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1132         set_fs(old_fs);
1133         if (put_compat_timespec(&t, interval))
1134                 return -EFAULT;
1135         return ret;
1136 }
1137
1138 /*
1139  * Allocate user-space memory for the duration of a single system call,
1140  * in order to marshall parameters inside a compat thunk.
1141  */
1142 void __user *compat_alloc_user_space(unsigned long len)
1143 {
1144         void __user *ptr;
1145
1146         /* If len would occupy more than half of the entire compat space... */
1147         if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1148                 return NULL;
1149
1150         ptr = arch_compat_alloc_user_space(len);
1151
1152         if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1153                 return NULL;
1154
1155         return ptr;
1156 }
1157 EXPORT_SYMBOL_GPL(compat_alloc_user_space);