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/futex.h>        /* for FUTEX_WAIT */
  21 #include <linux/syscalls.h>
  22 #include <linux/unistd.h>
  23 #include <linux/security.h>
  24
  25 #include <asm/uaccess.h>
  26
  27 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
  28 {
  29         return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
  30                         __get_user(ts->tv_sec, &cts->tv_sec) ||
  31                         __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
  32 }
  33
  34 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
  35 {
  36         return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
  37                         __put_user(ts->tv_sec, &cts->tv_sec) ||
  38                         __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
  39 }
  40
  41 static long compat_nanosleep_restart(struct restart_block *restart)
  42 {
  43         unsigned long expire = restart->arg0, now = jiffies;
  44         struct compat_timespec __user *rmtp;
  45
  46         /* Did it expire while we handled signals? */
  47         if (!time_after(expire, now))
  48                 return 0;
  49
  50         expire = schedule_timeout_interruptible(expire - now);
  51         if (expire == 0)
  52                 return 0;
  53
  54         rmtp = (struct compat_timespec __user *)restart->arg1;
  55         if (rmtp) {
  56                 struct compat_timespec ct;
  57                 struct timespec t;
  58
  59                 jiffies_to_timespec(expire, &t);
  60                 ct.tv_sec = t.tv_sec;
  61                 ct.tv_nsec = t.tv_nsec;
  62                 if (copy_to_user(rmtp, &ct, sizeof(ct)))
  63                         return -EFAULT;
  64         }
  65         /* The 'restart' block is already filled in */
  66         return -ERESTART_RESTARTBLOCK;
  67 }
  68
  69 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
  70                 struct compat_timespec __user *rmtp)
  71 {
  72         struct timespec t;
  73         struct restart_block *restart;
  74         unsigned long expire;
  75
  76         if (get_compat_timespec(&t, rqtp))
  77                 return -EFAULT;
  78
  79         if ((t.tv_nsec >= 1000000000L) || (t.tv_nsec < 0) || (t.tv_sec < 0))
  80                 return -EINVAL;
  81
  82         expire = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
  83         expire = schedule_timeout_interruptible(expire);
  84         if (expire == 0)
  85                 return 0;
  86
  87         if (rmtp) {
  88                 jiffies_to_timespec(expire, &t);
  89                 if (put_compat_timespec(&t, rmtp))
  90                         return -EFAULT;
  91         }
  92         restart = &current_thread_info()->restart_block;
  93         restart->fn = compat_nanosleep_restart;
  94         restart->arg0 = jiffies + expire;
  95         restart->arg1 = (unsigned long) rmtp;
  96         return -ERESTART_RESTARTBLOCK;
  97 }
  98
  99 static inline long get_compat_itimerval(struct itimerval *o,
 100                 struct compat_itimerval __user *i)
 101 {
 102         return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
 103                 (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
 104                  __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
 105                  __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
 106                  __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
 107 }
 108
 109 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
 110                 struct itimerval *i)
 111 {
 112         return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
 113                 (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
 114                  __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
 115                  __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
 116                  __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
 117 }
 118
 119 asmlinkage long compat_sys_getitimer(int which,
 120                 struct compat_itimerval __user *it)
 121 {
 122         struct itimerval kit;
 123         int error;
 124
 125         error = do_getitimer(which, &kit);
 126         if (!error && put_compat_itimerval(it, &kit))
 127                 error = -EFAULT;
 128         return error;
 129 }
 130
 131 asmlinkage long compat_sys_setitimer(int which,
 132                 struct compat_itimerval __user *in,
 133                 struct compat_itimerval __user *out)
 134 {
 135         struct itimerval kin, kout;
 136         int error;
 137
 138         if (in) {
 139                 if (get_compat_itimerval(&kin, in))
 140                         return -EFAULT;
 141         } else
 142                 memset(&kin, 0, sizeof(kin));
 143
 144         error = do_setitimer(which, &kin, out ? &kout : NULL);
 145         if (error || !out)
 146                 return error;
 147         if (put_compat_itimerval(out, &kout))
 148                 return -EFAULT;
 149         return 0;
 150 }
 151
 152 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
 153 {
 154         /*
 155          *      In the SMP world we might just be unlucky and have one of
 156          *      the times increment as we use it. Since the value is an
 157          *      atomically safe type this is just fine. Conceptually its
 158          *      as if the syscall took an instant longer to occur.
 159          */
 160         if (tbuf) {
 161                 struct compat_tms tmp;
 162                 struct task_struct *tsk = current;
 163                 struct task_struct *t;
 164                 cputime_t utime, stime, cutime, cstime;
 165
 166                 read_lock(&tasklist_lock);
 167                 utime = tsk->signal->utime;
 168                 stime = tsk->signal->stime;
 169                 t = tsk;
 170                 do {
 171                         utime = cputime_add(utime, t->utime);
 172                         stime = cputime_add(stime, t->stime);
 173                         t = next_thread(t);
 174                 } while (t != tsk);
 175
 176                 /*
 177                  * While we have tasklist_lock read-locked, no dying thread
 178                  * can be updating current->signal->[us]time.  Instead,
 179                  * we got their counts included in the live thread loop.
 180                  * However, another thread can come in right now and
 181                  * do a wait call that updates current->signal->c[us]time.
 182                  * To make sure we always see that pair updated atomically,
 183                  * we take the siglock around fetching them.
 184                  */
 185                 spin_lock_irq(&tsk->sighand->siglock);
 186                 cutime = tsk->signal->cutime;
 187                 cstime = tsk->signal->cstime;
 188                 spin_unlock_irq(&tsk->sighand->siglock);
 189                 read_unlock(&tasklist_lock);
 190
 191                 tmp.tms_utime = compat_jiffies_to_clock_t(cputime_to_jiffies(utime));
 192                 tmp.tms_stime = compat_jiffies_to_clock_t(cputime_to_jiffies(stime));
 193                 tmp.tms_cutime = compat_jiffies_to_clock_t(cputime_to_jiffies(cutime));
 194                 tmp.tms_cstime = compat_jiffies_to_clock_t(cputime_to_jiffies(cstime));
 195                 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
 196                         return -EFAULT;
 197         }
 198         return compat_jiffies_to_clock_t(jiffies);
 199 }
 200
 201 /*
 202  * Assumption: old_sigset_t and compat_old_sigset_t are both
 203  * types that can be passed to put_user()/get_user().
 204  */
 205
 206 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
 207 {
 208         old_sigset_t s;
 209         long ret;
 210         mm_segment_t old_fs = get_fs();
 211
 212         set_fs(KERNEL_DS);
 213         ret = sys_sigpending((old_sigset_t __user *) &s);
 214         set_fs(old_fs);
 215         if (ret == 0)
 216                 ret = put_user(s, set);
 217         return ret;
 218 }
 219
 220 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
 221                 compat_old_sigset_t __user *oset)
 222 {
 223         old_sigset_t s;
 224         long ret;
 225         mm_segment_t old_fs;
 226
 227         if (set && get_user(s, set))
 228                 return -EFAULT;
 229         old_fs = get_fs();
 230         set_fs(KERNEL_DS);
 231         ret = sys_sigprocmask(how,
 232                               set ? (old_sigset_t __user *) &s : NULL,
 233                               oset ? (old_sigset_t __user *) &s : NULL);
 234         set_fs(old_fs);
 235         if (ret == 0)
 236                 if (oset)
 237                         ret = put_user(s, oset);
 238         return ret;
 239 }
 240
 241 #ifdef CONFIG_FUTEX
 242 asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, int val,
 243                 struct compat_timespec __user *utime, u32 __user *uaddr2,
 244                 int val3)
 245 {
 246         struct timespec t;
 247         unsigned long timeout = MAX_SCHEDULE_TIMEOUT;
 248         int val2 = 0;
 249
 250         if ((op == FUTEX_WAIT) && utime) {
 251                 if (get_compat_timespec(&t, utime))
 252                         return -EFAULT;
 253                 timeout = timespec_to_jiffies(&t) + 1;
 254         }
 255         if (op >= FUTEX_REQUEUE)
 256                 val2 = (int) (unsigned long) utime;
 257
 258         return do_futex((unsigned long)uaddr, op, val, timeout,
 259                         (unsigned long)uaddr2, val2, val3);
 260 }
 261 #endif
 262
 263 asmlinkage long compat_sys_setrlimit(unsigned int resource,
 264                 struct compat_rlimit __user *rlim)
 265 {
 266         struct rlimit r;
 267         int ret;
 268         mm_segment_t old_fs = get_fs ();
 269
 270         if (resource >= RLIM_NLIMITS)
 271                 return -EINVAL;
 272
 273         if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
 274             __get_user(r.rlim_cur, &rlim->rlim_cur) ||
 275             __get_user(r.rlim_max, &rlim->rlim_max))
 276                 return -EFAULT;
 277
 278         if (r.rlim_cur == COMPAT_RLIM_INFINITY)
 279                 r.rlim_cur = RLIM_INFINITY;
 280         if (r.rlim_max == COMPAT_RLIM_INFINITY)
 281                 r.rlim_max = RLIM_INFINITY;
 282         set_fs(KERNEL_DS);
 283         ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
 284         set_fs(old_fs);
 285         return ret;
 286 }
 287
 288 #ifdef COMPAT_RLIM_OLD_INFINITY
 289
 290 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
 291                 struct compat_rlimit __user *rlim)
 292 {
 293         struct rlimit r;
 294         int ret;
 295         mm_segment_t old_fs = get_fs();
 296
 297         set_fs(KERNEL_DS);
 298         ret = sys_old_getrlimit(resource, &r);
 299         set_fs(old_fs);
 300
 301         if (!ret) {
 302                 if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
 303                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 304                 if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
 305                         r.rlim_max = COMPAT_RLIM_INFINITY;
 306
 307                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 308                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 309                     __put_user(r.rlim_max, &rlim->rlim_max))
 310                         return -EFAULT;
 311         }
 312         return ret;
 313 }
 314
 315 #endif
 316
 317 asmlinkage long compat_sys_getrlimit (unsigned int resource,
 318                 struct compat_rlimit __user *rlim)
 319 {
 320         struct rlimit r;
 321         int ret;
 322         mm_segment_t old_fs = get_fs();
 323
 324         set_fs(KERNEL_DS);
 325         ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
 326         set_fs(old_fs);
 327         if (!ret) {
 328                 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
 329                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 330                 if (r.rlim_max > COMPAT_RLIM_INFINITY)
 331                         r.rlim_max = COMPAT_RLIM_INFINITY;
 332
 333                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 334                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 335                     __put_user(r.rlim_max, &rlim->rlim_max))
 336                         return -EFAULT;
 337         }
 338         return ret;
 339 }
 340
 341 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 342 {
 343         if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
 344             __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
 345             __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
 346             __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
 347             __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
 348             __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
 349             __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
 350             __put_user(r->ru_idrss, &ru->ru_idrss) ||
 351             __put_user(r->ru_isrss, &ru->ru_isrss) ||
 352             __put_user(r->ru_minflt, &ru->ru_minflt) ||
 353             __put_user(r->ru_majflt, &ru->ru_majflt) ||
 354             __put_user(r->ru_nswap, &ru->ru_nswap) ||
 355             __put_user(r->ru_inblock, &ru->ru_inblock) ||
 356             __put_user(r->ru_oublock, &ru->ru_oublock) ||
 357             __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
 358             __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
 359             __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
 360             __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
 361             __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
 362                 return -EFAULT;
 363         return 0;
 364 }
 365
 366 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
 367 {
 368         struct rusage r;
 369         int ret;
 370         mm_segment_t old_fs = get_fs();
 371
 372         set_fs(KERNEL_DS);
 373         ret = sys_getrusage(who, (struct rusage __user *) &r);
 374         set_fs(old_fs);
 375
 376         if (ret)
 377                 return ret;
 378
 379         if (put_compat_rusage(&r, ru))
 380                 return -EFAULT;
 381
 382         return 0;
 383 }
 384
 385 asmlinkage long
 386 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
 387         struct compat_rusage __user *ru)
 388 {
 389         if (!ru) {
 390                 return sys_wait4(pid, stat_addr, options, NULL);
 391         } else {
 392                 struct rusage r;
 393                 int ret;
 394                 unsigned int status;
 395                 mm_segment_t old_fs = get_fs();
 396
 397                 set_fs (KERNEL_DS);
 398                 ret = sys_wait4(pid,
 399                                 (stat_addr ?
 400                                  (unsigned int __user *) &status : NULL),
 401                                 options, (struct rusage __user *) &r);
 402                 set_fs (old_fs);
 403
 404                 if (ret > 0) {
 405                         if (put_compat_rusage(&r, ru))
 406                                 return -EFAULT;
 407                         if (stat_addr && put_user(status, stat_addr))
 408                                 return -EFAULT;
 409                 }
 410                 return ret;
 411         }
 412 }
 413
 414 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
 415                 struct compat_siginfo __user *uinfo, int options,
 416                 struct compat_rusage __user *uru)
 417 {
 418         siginfo_t info;
 419         struct rusage ru;
 420         long ret;
 421         mm_segment_t old_fs = get_fs();
 422
 423         memset(&info, 0, sizeof(info));
 424
 425         set_fs(KERNEL_DS);
 426         ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 427                          uru ? (struct rusage __user *)&ru : NULL);
 428         set_fs(old_fs);
 429
 430         if ((ret < 0) || (info.si_signo == 0))
 431                 return ret;
 432
 433         if (uru) {
 434                 ret = put_compat_rusage(&ru, uru);
 435                 if (ret)
 436                         return ret;
 437         }
 438
 439         BUG_ON(info.si_code & __SI_MASK);
 440         info.si_code |= __SI_CHLD;
 441         return copy_siginfo_to_user32(uinfo, &info);
 442 }
 443
 444 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 445                                     unsigned len, cpumask_t *new_mask)
 446 {
 447         unsigned long *k;
 448
 449         if (len < sizeof(cpumask_t))
 450                 memset(new_mask, 0, sizeof(cpumask_t));
 451         else if (len > sizeof(cpumask_t))
 452                 len = sizeof(cpumask_t);
 453
 454         k = cpus_addr(*new_mask);
 455         return compat_get_bitmap(k, user_mask_ptr, len * 8);
 456 }
 457
 458 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
 459                                              unsigned int len,
 460                                              compat_ulong_t __user *user_mask_ptr)
 461 {
 462         cpumask_t new_mask;
 463         int retval;
 464
 465         retval = compat_get_user_cpu_mask(user_mask_ptr, len, &new_mask);
 466         if (retval)
 467                 return retval;
 468
 469         return sched_setaffinity(pid, new_mask);
 470 }
 471
 472 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 473                                              compat_ulong_t __user *user_mask_ptr)
 474 {
 475         int ret;
 476         cpumask_t mask;
 477         unsigned long *k;
 478         unsigned int min_length = sizeof(cpumask_t);
 479
 480         if (NR_CPUS <= BITS_PER_COMPAT_LONG)
 481                 min_length = sizeof(compat_ulong_t);
 482
 483         if (len < min_length)
 484                 return -EINVAL;
 485
 486         ret = sched_getaffinity(pid, &mask);
 487         if (ret < 0)
 488                 return ret;
 489
 490         k = cpus_addr(mask);
 491         ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
 492         if (ret)
 493                 return ret;
 494
 495         return min_length;
 496 }
 497
 498 static int get_compat_itimerspec(struct itimerspec *dst,
 499                                  struct compat_itimerspec __user *src)
 500 {
 501         if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
 502             get_compat_timespec(&dst->it_value, &src->it_value))
 503                 return -EFAULT;
 504         return 0;
 505 }
 506
 507 static int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 508                                  struct itimerspec *src)
 509 {
 510         if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
 511             put_compat_timespec(&src->it_value, &dst->it_value))
 512                 return -EFAULT;
 513         return 0;
 514 }
 515
 516 long compat_sys_timer_create(clockid_t which_clock,
 517                         struct compat_sigevent __user *timer_event_spec,
 518                         timer_t __user *created_timer_id)
 519 {
 520         struct sigevent __user *event = NULL;
 521
 522         if (timer_event_spec) {
 523                 struct sigevent kevent;
 524
 525                 event = compat_alloc_user_space(sizeof(*event));
 526                 if (get_compat_sigevent(&kevent, timer_event_spec) ||
 527                     copy_to_user(event, &kevent, sizeof(*event)))
 528                         return -EFAULT;
 529         }
 530
 531         return sys_timer_create(which_clock, event, created_timer_id);
 532 }
 533
 534 long compat_sys_timer_settime(timer_t timer_id, int flags,
 535                           struct compat_itimerspec __user *new,
 536                           struct compat_itimerspec __user *old)
 537 {
 538         long err;
 539         mm_segment_t oldfs;
 540         struct itimerspec newts, oldts;
 541
 542         if (!new)
 543                 return -EINVAL;
 544         if (get_compat_itimerspec(&newts, new))
 545                 return -EFAULT;
 546         oldfs = get_fs();
 547         set_fs(KERNEL_DS);
 548         err = sys_timer_settime(timer_id, flags,
 549                                 (struct itimerspec __user *) &newts,
 550                                 (struct itimerspec __user *) &oldts);
 551         set_fs(oldfs);
 552         if (!err && old && put_compat_itimerspec(old, &oldts))
 553                 return -EFAULT;
 554         return err;
 555 }
 556
 557 long compat_sys_timer_gettime(timer_t timer_id,
 558                 struct compat_itimerspec __user *setting)
 559 {
 560         long err;
 561         mm_segment_t oldfs;
 562         struct itimerspec ts;
 563
 564         oldfs = get_fs();
 565         set_fs(KERNEL_DS);
 566         err = sys_timer_gettime(timer_id,
 567                                 (struct itimerspec __user *) &ts);
 568         set_fs(oldfs);
 569         if (!err && put_compat_itimerspec(setting, &ts))
 570                 return -EFAULT;
 571         return err;
 572 }
 573
 574 long compat_sys_clock_settime(clockid_t which_clock,
 575                 struct compat_timespec __user *tp)
 576 {
 577         long err;
 578         mm_segment_t oldfs;
 579         struct timespec ts;
 580
 581         if (get_compat_timespec(&ts, tp))
 582                 return -EFAULT;
 583         oldfs = get_fs();
 584         set_fs(KERNEL_DS);
 585         err = sys_clock_settime(which_clock,
 586                                 (struct timespec __user *) &ts);
 587         set_fs(oldfs);
 588         return err;
 589 }
 590
 591 long compat_sys_clock_gettime(clockid_t which_clock,
 592                 struct compat_timespec __user *tp)
 593 {
 594         long err;
 595         mm_segment_t oldfs;
 596         struct timespec ts;
 597
 598         oldfs = get_fs();
 599         set_fs(KERNEL_DS);
 600         err = sys_clock_gettime(which_clock,
 601                                 (struct timespec __user *) &ts);
 602         set_fs(oldfs);
 603         if (!err && put_compat_timespec(&ts, tp))
 604                 return -EFAULT;
 605         return err;
 606 }
 607
 608 long compat_sys_clock_getres(clockid_t which_clock,
 609                 struct compat_timespec __user *tp)
 610 {
 611         long err;
 612         mm_segment_t oldfs;
 613         struct timespec ts;
 614
 615         oldfs = get_fs();
 616         set_fs(KERNEL_DS);
 617         err = sys_clock_getres(which_clock,
 618                                (struct timespec __user *) &ts);
 619         set_fs(oldfs);
 620         if (!err && tp && put_compat_timespec(&ts, tp))
 621                 return -EFAULT;
 622         return err;
 623 }
 624
 625 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
 626                             struct compat_timespec __user *rqtp,
 627                             struct compat_timespec __user *rmtp)
 628 {
 629         long err;
 630         mm_segment_t oldfs;
 631         struct timespec in, out;
 632
 633         if (get_compat_timespec(&in, rqtp))
 634                 return -EFAULT;
 635
 636         oldfs = get_fs();
 637         set_fs(KERNEL_DS);
 638         err = sys_clock_nanosleep(which_clock, flags,
 639                                   (struct timespec __user *) &in,
 640                                   (struct timespec __user *) &out);
 641         set_fs(oldfs);
 642         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 643             put_compat_timespec(&out, rmtp))
 644                 return -EFAULT;
 645         return err;
 646 }
 647
 648 /*
 649  * We currently only need the following fields from the sigevent
 650  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 651  * sigev_notify_thread_id).  The others are handled in user mode.
 652  * We also assume that copying sigev_value.sival_int is sufficient
 653  * to keep all the bits of sigev_value.sival_ptr intact.
 654  */
 655 int get_compat_sigevent(struct sigevent *event,
 656                 const struct compat_sigevent __user *u_event)
 657 {
 658         memset(event, 0, sizeof(*event));
 659         return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 660                 __get_user(event->sigev_value.sival_int,
 661                         &u_event->sigev_value.sival_int) ||
 662                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
 663                 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
 664                 __get_user(event->sigev_notify_thread_id,
 665                         &u_event->sigev_notify_thread_id))
 666                 ? -EFAULT : 0;
 667 }
 668
 669 long compat_get_bitmap(unsigned long *mask, compat_ulong_t __user *umask,
 670                        unsigned long bitmap_size)
 671 {
 672         int i, j;
 673         unsigned long m;
 674         compat_ulong_t um;
 675         unsigned long nr_compat_longs;
 676
 677         /* align bitmap up to nearest compat_long_t boundary */
 678         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 679
 680         if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 681                 return -EFAULT;
 682
 683         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 684
 685         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 686                 m = 0;
 687
 688                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 689                         /*
 690                          * We dont want to read past the end of the userspace
 691                          * bitmap. We must however ensure the end of the
 692                          * kernel bitmap is zeroed.
 693                          */
 694                         if (nr_compat_longs-- > 0) {
 695                                 if (__get_user(um, umask))
 696                                         return -EFAULT;
 697                         } else {
 698                                 um = 0;
 699                         }
 700
 701                         umask++;
 702                         m |= (long)um << (j * BITS_PER_COMPAT_LONG);
 703                 }
 704                 *mask++ = m;
 705         }
 706
 707         return 0;
 708 }
 709
 710 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 711                        unsigned long bitmap_size)
 712 {
 713         int i, j;
 714         unsigned long m;
 715         compat_ulong_t um;
 716         unsigned long nr_compat_longs;
 717
 718         /* align bitmap up to nearest compat_long_t boundary */
 719         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 720
 721         if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 722                 return -EFAULT;
 723
 724         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 725
 726         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 727                 m = *mask++;
 728
 729                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 730                         um = m;
 731
 732                         /*
 733                          * We dont want to write past the end of the userspace
 734                          * bitmap.
 735                          */
 736                         if (nr_compat_longs-- > 0) {
 737                                 if (__put_user(um, umask))
 738                                         return -EFAULT;
 739                         }
 740
 741                         umask++;
 742                         m >>= 4*sizeof(um);
 743                         m >>= 4*sizeof(um);
 744                 }
 745         }
 746
 747         return 0;
 748 }
 749
 750 void
 751 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
 752 {
 753         switch (_NSIG_WORDS) {
 754 #if defined (__COMPAT_ENDIAN_SWAP__)
 755         case 4: set->sig[3] = compat->sig[7] | (((long)compat->sig[6]) << 32 );
 756         case 3: set->sig[2] = compat->sig[5] | (((long)compat->sig[4]) << 32 );
 757         case 2: set->sig[1] = compat->sig[3] | (((long)compat->sig[2]) << 32 );
 758         case 1: set->sig[0] = compat->sig[1] | (((long)compat->sig[0]) << 32 );
 759 #else
 760         case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
 761         case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
 762         case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
 763         case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
 764 #endif
 765         }
 766 }
 767
 768 asmlinkage long
 769 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
 770                 struct compat_siginfo __user *uinfo,
 771                 struct compat_timespec __user *uts, compat_size_t sigsetsize)
 772 {
 773         compat_sigset_t s32;
 774         sigset_t s;
 775         int sig;
 776         struct timespec t;
 777         siginfo_t info;
 778         long ret, timeout = 0;
 779
 780         if (sigsetsize != sizeof(sigset_t))
 781                 return -EINVAL;
 782
 783         if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
 784                 return -EFAULT;
 785         sigset_from_compat(&s, &s32);
 786         sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
 787         signotset(&s);
 788
 789         if (uts) {
 790                 if (get_compat_timespec (&t, uts))
 791                         return -EFAULT;
 792                 if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
 793                                 || t.tv_sec < 0)
 794                         return -EINVAL;
 795         }
 796
 797         spin_lock_irq(&current->sighand->siglock);
 798         sig = dequeue_signal(current, &s, &info);
 799         if (!sig) {
 800                 timeout = MAX_SCHEDULE_TIMEOUT;
 801                 if (uts)
 802                         timeout = timespec_to_jiffies(&t)
 803                                 +(t.tv_sec || t.tv_nsec);
 804                 if (timeout) {
 805                         current->real_blocked = current->blocked;
 806                         sigandsets(&current->blocked, &current->blocked, &s);
 807
 808                         recalc_sigpending();
 809                         spin_unlock_irq(&current->sighand->siglock);
 810
 811                         timeout = schedule_timeout_interruptible(timeout);
 812
 813                         spin_lock_irq(&current->sighand->siglock);
 814                         sig = dequeue_signal(current, &s, &info);
 815                         current->blocked = current->real_blocked;
 816                         siginitset(&current->real_blocked, 0);
 817                         recalc_sigpending();
 818                 }
 819         }
 820         spin_unlock_irq(&current->sighand->siglock);
 821
 822         if (sig) {
 823                 ret = sig;
 824                 if (uinfo) {
 825                         if (copy_siginfo_to_user32(uinfo, &info))
 826                                 ret = -EFAULT;
 827                 }
 828         }else {
 829                 ret = timeout?-EINTR:-EAGAIN;
 830         }
 831         return ret;
 832
 833 }
 834
 835 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
 836
 837 /* compat_time_t is a 32 bit "long" and needs to get converted. */
 838
 839 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
 840 {
 841         compat_time_t i;
 842         struct timeval tv;
 843
 844         do_gettimeofday(&tv);
 845         i = tv.tv_sec;
 846
 847         if (tloc) {
 848                 if (put_user(i,tloc))
 849                         i = -EFAULT;
 850         }
 851         return i;
 852 }
 853
 854 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
 855 {
 856         struct timespec tv;
 857         int err;
 858
 859         if (get_user(tv.tv_sec, tptr))
 860                 return -EFAULT;
 861
 862         tv.tv_nsec = 0;
 863
 864         err = security_settime(&tv, NULL);
 865         if (err)
 866                 return err;
 867
 868         do_settimeofday(&tv);
 869         return 0;
 870 }
 871
 872 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
 873
 874 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 875 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
 876 {
 877         sigset_t newset;
 878         compat_sigset_t newset32;
 879
 880         /* XXX: Don't preclude handling different sized sigset_t's.  */
 881         if (sigsetsize != sizeof(sigset_t))
 882                 return -EINVAL;
 883
 884         if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
 885                 return -EFAULT;
 886         sigset_from_compat(&newset, &newset32);
 887         sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 888
 889         spin_lock_irq(&current->sighand->siglock);
 890         current->saved_sigmask = current->blocked;
 891         current->blocked = newset;
 892         recalc_sigpending();
 893         spin_unlock_irq(&current->sighand->siglock);
 894
 895         current->state = TASK_INTERRUPTIBLE;
 896         schedule();
 897         set_thread_flag(TIF_RESTORE_SIGMASK);
 898         return -ERESTARTNOHAND;
 899 }
 900 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */