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