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
  26 #include <asm/uaccess.h>
  27
  28 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
  29 {
  30         return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
  31                         __get_user(ts->tv_sec, &cts->tv_sec) ||
  32                         __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
  33 }
  34
  35 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
  36 {
  37         return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
  38                         __put_user(ts->tv_sec, &cts->tv_sec) ||
  39                         __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
  40 }
  41
  42 static long compat_nanosleep_restart(struct restart_block *restart)
  43 {
  44         unsigned long expire = restart->arg0, now = jiffies;
  45         struct compat_timespec __user *rmtp;
  46
  47         /* Did it expire while we handled signals? */
  48         if (!time_after(expire, now))
  49                 return 0;
  50
  51         expire = schedule_timeout_interruptible(expire - now);
  52         if (expire == 0)
  53                 return 0;
  54
  55         rmtp = (struct compat_timespec __user *)restart->arg1;
  56         if (rmtp) {
  57                 struct compat_timespec ct;
  58                 struct timespec t;
  59
  60                 jiffies_to_timespec(expire, &t);
  61                 ct.tv_sec = t.tv_sec;
  62                 ct.tv_nsec = t.tv_nsec;
  63                 if (copy_to_user(rmtp, &ct, sizeof(ct)))
  64                         return -EFAULT;
  65         }
  66         /* The 'restart' block is already filled in */
  67         return -ERESTART_RESTARTBLOCK;
  68 }
  69
  70 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
  71                 struct compat_timespec __user *rmtp)
  72 {
  73         struct timespec t;
  74         struct restart_block *restart;
  75         unsigned long expire;
  76
  77         if (get_compat_timespec(&t, rqtp))
  78                 return -EFAULT;
  79
  80         if ((t.tv_nsec >= 1000000000L) || (t.tv_nsec < 0) || (t.tv_sec < 0))
  81                 return -EINVAL;
  82
  83         expire = timespec_to_jiffies(&t) + (t.tv_sec || t.tv_nsec);
  84         expire = schedule_timeout_interruptible(expire);
  85         if (expire == 0)
  86                 return 0;
  87
  88         if (rmtp) {
  89                 jiffies_to_timespec(expire, &t);
  90                 if (put_compat_timespec(&t, rmtp))
  91                         return -EFAULT;
  92         }
  93         restart = &current_thread_info()->restart_block;
  94         restart->fn = compat_nanosleep_restart;
  95         restart->arg0 = jiffies + expire;
  96         restart->arg1 = (unsigned long) rmtp;
  97         return -ERESTART_RESTARTBLOCK;
  98 }
  99
 100 static inline long get_compat_itimerval(struct itimerval *o,
 101                 struct compat_itimerval __user *i)
 102 {
 103         return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
 104                 (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
 105                  __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
 106                  __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
 107                  __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
 108 }
 109
 110 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
 111                 struct itimerval *i)
 112 {
 113         return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
 114                 (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
 115                  __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
 116                  __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
 117                  __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
 118 }
 119
 120 asmlinkage long compat_sys_getitimer(int which,
 121                 struct compat_itimerval __user *it)
 122 {
 123         struct itimerval kit;
 124         int error;
 125
 126         error = do_getitimer(which, &kit);
 127         if (!error && put_compat_itimerval(it, &kit))
 128                 error = -EFAULT;
 129         return error;
 130 }
 131
 132 asmlinkage long compat_sys_setitimer(int which,
 133                 struct compat_itimerval __user *in,
 134                 struct compat_itimerval __user *out)
 135 {
 136         struct itimerval kin, kout;
 137         int error;
 138
 139         if (in) {
 140                 if (get_compat_itimerval(&kin, in))
 141                         return -EFAULT;
 142         } else
 143                 memset(&kin, 0, sizeof(kin));
 144
 145         error = do_setitimer(which, &kin, out ? &kout : NULL);
 146         if (error || !out)
 147                 return error;
 148         if (put_compat_itimerval(out, &kout))
 149                 return -EFAULT;
 150         return 0;
 151 }
 152
 153 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
 154 {
 155         /*
 156          *      In the SMP world we might just be unlucky and have one of
 157          *      the times increment as we use it. Since the value is an
 158          *      atomically safe type this is just fine. Conceptually its
 159          *      as if the syscall took an instant longer to occur.
 160          */
 161         if (tbuf) {
 162                 struct compat_tms tmp;
 163                 struct task_struct *tsk = current;
 164                 struct task_struct *t;
 165                 cputime_t utime, stime, cutime, cstime;
 166
 167                 read_lock(&tasklist_lock);
 168                 utime = tsk->signal->utime;
 169                 stime = tsk->signal->stime;
 170                 t = tsk;
 171                 do {
 172                         utime = cputime_add(utime, t->utime);
 173                         stime = cputime_add(stime, t->stime);
 174                         t = next_thread(t);
 175                 } while (t != tsk);
 176
 177                 /*
 178                  * While we have tasklist_lock read-locked, no dying thread
 179                  * can be updating current->signal->[us]time.  Instead,
 180                  * we got their counts included in the live thread loop.
 181                  * However, another thread can come in right now and
 182                  * do a wait call that updates current->signal->c[us]time.
 183                  * To make sure we always see that pair updated atomically,
 184                  * we take the siglock around fetching them.
 185                  */
 186                 spin_lock_irq(&tsk->sighand->siglock);
 187                 cutime = tsk->signal->cutime;
 188                 cstime = tsk->signal->cstime;
 189                 spin_unlock_irq(&tsk->sighand->siglock);
 190                 read_unlock(&tasklist_lock);
 191
 192                 tmp.tms_utime = compat_jiffies_to_clock_t(cputime_to_jiffies(utime));
 193                 tmp.tms_stime = compat_jiffies_to_clock_t(cputime_to_jiffies(stime));
 194                 tmp.tms_cutime = compat_jiffies_to_clock_t(cputime_to_jiffies(cutime));
 195                 tmp.tms_cstime = compat_jiffies_to_clock_t(cputime_to_jiffies(cstime));
 196                 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
 197                         return -EFAULT;
 198         }
 199         return compat_jiffies_to_clock_t(jiffies);
 200 }
 201
 202 /*
 203  * Assumption: old_sigset_t and compat_old_sigset_t are both
 204  * types that can be passed to put_user()/get_user().
 205  */
 206
 207 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
 208 {
 209         old_sigset_t s;
 210         long ret;
 211         mm_segment_t old_fs = get_fs();
 212
 213         set_fs(KERNEL_DS);
 214         ret = sys_sigpending((old_sigset_t __user *) &s);
 215         set_fs(old_fs);
 216         if (ret == 0)
 217                 ret = put_user(s, set);
 218         return ret;
 219 }
 220
 221 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
 222                 compat_old_sigset_t __user *oset)
 223 {
 224         old_sigset_t s;
 225         long ret;
 226         mm_segment_t old_fs;
 227
 228         if (set && get_user(s, set))
 229                 return -EFAULT;
 230         old_fs = get_fs();
 231         set_fs(KERNEL_DS);
 232         ret = sys_sigprocmask(how,
 233                               set ? (old_sigset_t __user *) &s : NULL,
 234                               oset ? (old_sigset_t __user *) &s : NULL);
 235         set_fs(old_fs);
 236         if (ret == 0)
 237                 if (oset)
 238                         ret = put_user(s, oset);
 239         return ret;
 240 }
 241
 242 asmlinkage long compat_sys_setrlimit(unsigned int resource,
 243                 struct compat_rlimit __user *rlim)
 244 {
 245         struct rlimit r;
 246         int ret;
 247         mm_segment_t old_fs = get_fs ();
 248
 249         if (resource >= RLIM_NLIMITS)
 250                 return -EINVAL;
 251
 252         if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
 253             __get_user(r.rlim_cur, &rlim->rlim_cur) ||
 254             __get_user(r.rlim_max, &rlim->rlim_max))
 255                 return -EFAULT;
 256
 257         if (r.rlim_cur == COMPAT_RLIM_INFINITY)
 258                 r.rlim_cur = RLIM_INFINITY;
 259         if (r.rlim_max == COMPAT_RLIM_INFINITY)
 260                 r.rlim_max = RLIM_INFINITY;
 261         set_fs(KERNEL_DS);
 262         ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
 263         set_fs(old_fs);
 264         return ret;
 265 }
 266
 267 #ifdef COMPAT_RLIM_OLD_INFINITY
 268
 269 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
 270                 struct compat_rlimit __user *rlim)
 271 {
 272         struct rlimit r;
 273         int ret;
 274         mm_segment_t old_fs = get_fs();
 275
 276         set_fs(KERNEL_DS);
 277         ret = sys_old_getrlimit(resource, &r);
 278         set_fs(old_fs);
 279
 280         if (!ret) {
 281                 if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
 282                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 283                 if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
 284                         r.rlim_max = COMPAT_RLIM_INFINITY;
 285
 286                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 287                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 288                     __put_user(r.rlim_max, &rlim->rlim_max))
 289                         return -EFAULT;
 290         }
 291         return ret;
 292 }
 293
 294 #endif
 295
 296 asmlinkage long compat_sys_getrlimit (unsigned int resource,
 297                 struct compat_rlimit __user *rlim)
 298 {
 299         struct rlimit r;
 300         int ret;
 301         mm_segment_t old_fs = get_fs();
 302
 303         set_fs(KERNEL_DS);
 304         ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
 305         set_fs(old_fs);
 306         if (!ret) {
 307                 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
 308                         r.rlim_cur = COMPAT_RLIM_INFINITY;
 309                 if (r.rlim_max > COMPAT_RLIM_INFINITY)
 310                         r.rlim_max = COMPAT_RLIM_INFINITY;
 311
 312                 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 313                     __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 314                     __put_user(r.rlim_max, &rlim->rlim_max))
 315                         return -EFAULT;
 316         }
 317         return ret;
 318 }
 319
 320 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 321 {
 322         if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
 323             __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
 324             __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
 325             __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
 326             __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
 327             __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
 328             __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
 329             __put_user(r->ru_idrss, &ru->ru_idrss) ||
 330             __put_user(r->ru_isrss, &ru->ru_isrss) ||
 331             __put_user(r->ru_minflt, &ru->ru_minflt) ||
 332             __put_user(r->ru_majflt, &ru->ru_majflt) ||
 333             __put_user(r->ru_nswap, &ru->ru_nswap) ||
 334             __put_user(r->ru_inblock, &ru->ru_inblock) ||
 335             __put_user(r->ru_oublock, &ru->ru_oublock) ||
 336             __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
 337             __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
 338             __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
 339             __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
 340             __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
 341                 return -EFAULT;
 342         return 0;
 343 }
 344
 345 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
 346 {
 347         struct rusage r;
 348         int ret;
 349         mm_segment_t old_fs = get_fs();
 350
 351         set_fs(KERNEL_DS);
 352         ret = sys_getrusage(who, (struct rusage __user *) &r);
 353         set_fs(old_fs);
 354
 355         if (ret)
 356                 return ret;
 357
 358         if (put_compat_rusage(&r, ru))
 359                 return -EFAULT;
 360
 361         return 0;
 362 }
 363
 364 asmlinkage long
 365 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
 366         struct compat_rusage __user *ru)
 367 {
 368         if (!ru) {
 369                 return sys_wait4(pid, stat_addr, options, NULL);
 370         } else {
 371                 struct rusage r;
 372                 int ret;
 373                 unsigned int status;
 374                 mm_segment_t old_fs = get_fs();
 375
 376                 set_fs (KERNEL_DS);
 377                 ret = sys_wait4(pid,
 378                                 (stat_addr ?
 379                                  (unsigned int __user *) &status : NULL),
 380                                 options, (struct rusage __user *) &r);
 381                 set_fs (old_fs);
 382
 383                 if (ret > 0) {
 384                         if (put_compat_rusage(&r, ru))
 385                                 return -EFAULT;
 386                         if (stat_addr && put_user(status, stat_addr))
 387                                 return -EFAULT;
 388                 }
 389                 return ret;
 390         }
 391 }
 392
 393 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
 394                 struct compat_siginfo __user *uinfo, int options,
 395                 struct compat_rusage __user *uru)
 396 {
 397         siginfo_t info;
 398         struct rusage ru;
 399         long ret;
 400         mm_segment_t old_fs = get_fs();
 401
 402         memset(&info, 0, sizeof(info));
 403
 404         set_fs(KERNEL_DS);
 405         ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 406                          uru ? (struct rusage __user *)&ru : NULL);
 407         set_fs(old_fs);
 408
 409         if ((ret < 0) || (info.si_signo == 0))
 410                 return ret;
 411
 412         if (uru) {
 413                 ret = put_compat_rusage(&ru, uru);
 414                 if (ret)
 415                         return ret;
 416         }
 417
 418         BUG_ON(info.si_code & __SI_MASK);
 419         info.si_code |= __SI_CHLD;
 420         return copy_siginfo_to_user32(uinfo, &info);
 421 }
 422
 423 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 424                                     unsigned len, cpumask_t *new_mask)
 425 {
 426         unsigned long *k;
 427
 428         if (len < sizeof(cpumask_t))
 429                 memset(new_mask, 0, sizeof(cpumask_t));
 430         else if (len > sizeof(cpumask_t))
 431                 len = sizeof(cpumask_t);
 432
 433         k = cpus_addr(*new_mask);
 434         return compat_get_bitmap(k, user_mask_ptr, len * 8);
 435 }
 436
 437 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
 438                                              unsigned int len,
 439                                              compat_ulong_t __user *user_mask_ptr)
 440 {
 441         cpumask_t new_mask;
 442         int retval;
 443
 444         retval = compat_get_user_cpu_mask(user_mask_ptr, len, &new_mask);
 445         if (retval)
 446                 return retval;
 447
 448         return sched_setaffinity(pid, new_mask);
 449 }
 450
 451 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 452                                              compat_ulong_t __user *user_mask_ptr)
 453 {
 454         int ret;
 455         cpumask_t mask;
 456         unsigned long *k;
 457         unsigned int min_length = sizeof(cpumask_t);
 458
 459         if (NR_CPUS <= BITS_PER_COMPAT_LONG)
 460                 min_length = sizeof(compat_ulong_t);
 461
 462         if (len < min_length)
 463                 return -EINVAL;
 464
 465         ret = sched_getaffinity(pid, &mask);
 466         if (ret < 0)
 467                 return ret;
 468
 469         k = cpus_addr(mask);
 470         ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
 471         if (ret)
 472                 return ret;
 473
 474         return min_length;
 475 }
 476
 477 static int get_compat_itimerspec(struct itimerspec *dst,
 478                                  struct compat_itimerspec __user *src)
 479 {
 480         if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
 481             get_compat_timespec(&dst->it_value, &src->it_value))
 482                 return -EFAULT;
 483         return 0;
 484 }
 485
 486 static int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 487                                  struct itimerspec *src)
 488 {
 489         if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
 490             put_compat_timespec(&src->it_value, &dst->it_value))
 491                 return -EFAULT;
 492         return 0;
 493 }
 494
 495 long compat_sys_timer_create(clockid_t which_clock,
 496                         struct compat_sigevent __user *timer_event_spec,
 497                         timer_t __user *created_timer_id)
 498 {
 499         struct sigevent __user *event = NULL;
 500
 501         if (timer_event_spec) {
 502                 struct sigevent kevent;
 503
 504                 event = compat_alloc_user_space(sizeof(*event));
 505                 if (get_compat_sigevent(&kevent, timer_event_spec) ||
 506                     copy_to_user(event, &kevent, sizeof(*event)))
 507                         return -EFAULT;
 508         }
 509
 510         return sys_timer_create(which_clock, event, created_timer_id);
 511 }
 512
 513 long compat_sys_timer_settime(timer_t timer_id, int flags,
 514                           struct compat_itimerspec __user *new,
 515                           struct compat_itimerspec __user *old)
 516 {
 517         long err;
 518         mm_segment_t oldfs;
 519         struct itimerspec newts, oldts;
 520
 521         if (!new)
 522                 return -EINVAL;
 523         if (get_compat_itimerspec(&newts, new))
 524                 return -EFAULT;
 525         oldfs = get_fs();
 526         set_fs(KERNEL_DS);
 527         err = sys_timer_settime(timer_id, flags,
 528                                 (struct itimerspec __user *) &newts,
 529                                 (struct itimerspec __user *) &oldts);
 530         set_fs(oldfs);
 531         if (!err && old && put_compat_itimerspec(old, &oldts))
 532                 return -EFAULT;
 533         return err;
 534 }
 535
 536 long compat_sys_timer_gettime(timer_t timer_id,
 537                 struct compat_itimerspec __user *setting)
 538 {
 539         long err;
 540         mm_segment_t oldfs;
 541         struct itimerspec ts;
 542
 543         oldfs = get_fs();
 544         set_fs(KERNEL_DS);
 545         err = sys_timer_gettime(timer_id,
 546                                 (struct itimerspec __user *) &ts);
 547         set_fs(oldfs);
 548         if (!err && put_compat_itimerspec(setting, &ts))
 549                 return -EFAULT;
 550         return err;
 551 }
 552
 553 long compat_sys_clock_settime(clockid_t which_clock,
 554                 struct compat_timespec __user *tp)
 555 {
 556         long err;
 557         mm_segment_t oldfs;
 558         struct timespec ts;
 559
 560         if (get_compat_timespec(&ts, tp))
 561                 return -EFAULT;
 562         oldfs = get_fs();
 563         set_fs(KERNEL_DS);
 564         err = sys_clock_settime(which_clock,
 565                                 (struct timespec __user *) &ts);
 566         set_fs(oldfs);
 567         return err;
 568 }
 569
 570 long compat_sys_clock_gettime(clockid_t which_clock,
 571                 struct compat_timespec __user *tp)
 572 {
 573         long err;
 574         mm_segment_t oldfs;
 575         struct timespec ts;
 576
 577         oldfs = get_fs();
 578         set_fs(KERNEL_DS);
 579         err = sys_clock_gettime(which_clock,
 580                                 (struct timespec __user *) &ts);
 581         set_fs(oldfs);
 582         if (!err && put_compat_timespec(&ts, tp))
 583                 return -EFAULT;
 584         return err;
 585 }
 586
 587 long compat_sys_clock_getres(clockid_t which_clock,
 588                 struct compat_timespec __user *tp)
 589 {
 590         long err;
 591         mm_segment_t oldfs;
 592         struct timespec ts;
 593
 594         oldfs = get_fs();
 595         set_fs(KERNEL_DS);
 596         err = sys_clock_getres(which_clock,
 597                                (struct timespec __user *) &ts);
 598         set_fs(oldfs);
 599         if (!err && tp && put_compat_timespec(&ts, tp))
 600                 return -EFAULT;
 601         return err;
 602 }
 603
 604 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
 605                             struct compat_timespec __user *rqtp,
 606                             struct compat_timespec __user *rmtp)
 607 {
 608         long err;
 609         mm_segment_t oldfs;
 610         struct timespec in, out;
 611
 612         if (get_compat_timespec(&in, rqtp))
 613                 return -EFAULT;
 614
 615         oldfs = get_fs();
 616         set_fs(KERNEL_DS);
 617         err = sys_clock_nanosleep(which_clock, flags,
 618                                   (struct timespec __user *) &in,
 619                                   (struct timespec __user *) &out);
 620         set_fs(oldfs);
 621         if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 622             put_compat_timespec(&out, rmtp))
 623                 return -EFAULT;
 624         return err;
 625 }
 626
 627 /*
 628  * We currently only need the following fields from the sigevent
 629  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 630  * sigev_notify_thread_id).  The others are handled in user mode.
 631  * We also assume that copying sigev_value.sival_int is sufficient
 632  * to keep all the bits of sigev_value.sival_ptr intact.
 633  */
 634 int get_compat_sigevent(struct sigevent *event,
 635                 const struct compat_sigevent __user *u_event)
 636 {
 637         memset(event, 0, sizeof(*event));
 638         return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 639                 __get_user(event->sigev_value.sival_int,
 640                         &u_event->sigev_value.sival_int) ||
 641                 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
 642                 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
 643                 __get_user(event->sigev_notify_thread_id,
 644                         &u_event->sigev_notify_thread_id))
 645                 ? -EFAULT : 0;
 646 }
 647
 648 long compat_get_bitmap(unsigned long *mask, compat_ulong_t __user *umask,
 649                        unsigned long bitmap_size)
 650 {
 651         int i, j;
 652         unsigned long m;
 653         compat_ulong_t um;
 654         unsigned long nr_compat_longs;
 655
 656         /* align bitmap up to nearest compat_long_t boundary */
 657         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 658
 659         if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 660                 return -EFAULT;
 661
 662         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 663
 664         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 665                 m = 0;
 666
 667                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 668                         /*
 669                          * We dont want to read past the end of the userspace
 670                          * bitmap. We must however ensure the end of the
 671                          * kernel bitmap is zeroed.
 672                          */
 673                         if (nr_compat_longs-- > 0) {
 674                                 if (__get_user(um, umask))
 675                                         return -EFAULT;
 676                         } else {
 677                                 um = 0;
 678                         }
 679
 680                         umask++;
 681                         m |= (long)um << (j * BITS_PER_COMPAT_LONG);
 682                 }
 683                 *mask++ = m;
 684         }
 685
 686         return 0;
 687 }
 688
 689 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
 690                        unsigned long bitmap_size)
 691 {
 692         int i, j;
 693         unsigned long m;
 694         compat_ulong_t um;
 695         unsigned long nr_compat_longs;
 696
 697         /* align bitmap up to nearest compat_long_t boundary */
 698         bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 699
 700         if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
 701                 return -EFAULT;
 702
 703         nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 704
 705         for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 706                 m = *mask++;
 707
 708                 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 709                         um = m;
 710
 711                         /*
 712                          * We dont want to write past the end of the userspace
 713                          * bitmap.
 714                          */
 715                         if (nr_compat_longs-- > 0) {
 716                                 if (__put_user(um, umask))
 717                                         return -EFAULT;
 718                         }
 719
 720                         umask++;
 721                         m >>= 4*sizeof(um);
 722                         m >>= 4*sizeof(um);
 723                 }
 724         }
 725
 726         return 0;
 727 }
 728
 729 void
 730 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
 731 {
 732         switch (_NSIG_WORDS) {
 733         case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
 734         case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
 735         case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
 736         case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
 737         }
 738 }
 739
 740 asmlinkage long
 741 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
 742                 struct compat_siginfo __user *uinfo,
 743                 struct compat_timespec __user *uts, compat_size_t sigsetsize)
 744 {
 745         compat_sigset_t s32;
 746         sigset_t s;
 747         int sig;
 748         struct timespec t;
 749         siginfo_t info;
 750         long ret, timeout = 0;
 751
 752         if (sigsetsize != sizeof(sigset_t))
 753                 return -EINVAL;
 754
 755         if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
 756                 return -EFAULT;
 757         sigset_from_compat(&s, &s32);
 758         sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
 759         signotset(&s);
 760
 761         if (uts) {
 762                 if (get_compat_timespec (&t, uts))
 763                         return -EFAULT;
 764                 if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
 765                                 || t.tv_sec < 0)
 766                         return -EINVAL;
 767         }
 768
 769         spin_lock_irq(&current->sighand->siglock);
 770         sig = dequeue_signal(current, &s, &info);
 771         if (!sig) {
 772                 timeout = MAX_SCHEDULE_TIMEOUT;
 773                 if (uts)
 774                         timeout = timespec_to_jiffies(&t)
 775                                 +(t.tv_sec || t.tv_nsec);
 776                 if (timeout) {
 777                         current->real_blocked = current->blocked;
 778                         sigandsets(&current->blocked, &current->blocked, &s);
 779
 780                         recalc_sigpending();
 781                         spin_unlock_irq(&current->sighand->siglock);
 782
 783                         timeout = schedule_timeout_interruptible(timeout);
 784
 785                         spin_lock_irq(&current->sighand->siglock);
 786                         sig = dequeue_signal(current, &s, &info);
 787                         current->blocked = current->real_blocked;
 788                         siginitset(&current->real_blocked, 0);
 789                         recalc_sigpending();
 790                 }
 791         }
 792         spin_unlock_irq(&current->sighand->siglock);
 793
 794         if (sig) {
 795                 ret = sig;
 796                 if (uinfo) {
 797                         if (copy_siginfo_to_user32(uinfo, &info))
 798                                 ret = -EFAULT;
 799                 }
 800         }else {
 801                 ret = timeout?-EINTR:-EAGAIN;
 802         }
 803         return ret;
 804
 805 }
 806
 807 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
 808
 809 /* compat_time_t is a 32 bit "long" and needs to get converted. */
 810
 811 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
 812 {
 813         compat_time_t i;
 814         struct timeval tv;
 815
 816         do_gettimeofday(&tv);
 817         i = tv.tv_sec;
 818
 819         if (tloc) {
 820                 if (put_user(i,tloc))
 821                         i = -EFAULT;
 822         }
 823         return i;
 824 }
 825
 826 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
 827 {
 828         struct timespec tv;
 829         int err;
 830
 831         if (get_user(tv.tv_sec, tptr))
 832                 return -EFAULT;
 833
 834         tv.tv_nsec = 0;
 835
 836         err = security_settime(&tv, NULL);
 837         if (err)
 838                 return err;
 839
 840         do_settimeofday(&tv);
 841         return 0;
 842 }
 843
 844 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
 845
 846 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
 847 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
 848 {
 849         sigset_t newset;
 850         compat_sigset_t newset32;
 851
 852         /* XXX: Don't preclude handling different sized sigset_t's.  */
 853         if (sigsetsize != sizeof(sigset_t))
 854                 return -EINVAL;
 855
 856         if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
 857                 return -EFAULT;
 858         sigset_from_compat(&newset, &newset32);
 859         sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
 860
 861         spin_lock_irq(&current->sighand->siglock);
 862         current->saved_sigmask = current->blocked;
 863         current->blocked = newset;
 864         recalc_sigpending();
 865         spin_unlock_irq(&current->sighand->siglock);
 866
 867         current->state = TASK_INTERRUPTIBLE;
 868         schedule();
 869         set_thread_flag(TIF_RESTORE_SIGMASK);
 870         return -ERESTARTNOHAND;
 871 }
 872 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
 873
 874 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
 875 {
 876         struct timex txc;
 877         int ret;
 878
 879         memset(&txc, 0, sizeof(struct timex));
 880
 881         if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
 882                         __get_user(txc.modes, &utp->modes) ||
 883                         __get_user(txc.offset, &utp->offset) ||
 884                         __get_user(txc.freq, &utp->freq) ||
 885                         __get_user(txc.maxerror, &utp->maxerror) ||
 886                         __get_user(txc.esterror, &utp->esterror) ||
 887                         __get_user(txc.status, &utp->status) ||
 888                         __get_user(txc.constant, &utp->constant) ||
 889                         __get_user(txc.precision, &utp->precision) ||
 890                         __get_user(txc.tolerance, &utp->tolerance) ||
 891                         __get_user(txc.time.tv_sec, &utp->time.tv_sec) ||
 892                         __get_user(txc.time.tv_usec, &utp->time.tv_usec) ||
 893                         __get_user(txc.tick, &utp->tick) ||
 894                         __get_user(txc.ppsfreq, &utp->ppsfreq) ||
 895                         __get_user(txc.jitter, &utp->jitter) ||
 896                         __get_user(txc.shift, &utp->shift) ||
 897                         __get_user(txc.stabil, &utp->stabil) ||
 898                         __get_user(txc.jitcnt, &utp->jitcnt) ||
 899                         __get_user(txc.calcnt, &utp->calcnt) ||
 900                         __get_user(txc.errcnt, &utp->errcnt) ||
 901                         __get_user(txc.stbcnt, &utp->stbcnt))
 902                 return -EFAULT;
 903
 904         ret = do_adjtimex(&txc);
 905
 906         if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
 907                         __put_user(txc.modes, &utp->modes) ||
 908                         __put_user(txc.offset, &utp->offset) ||
 909                         __put_user(txc.freq, &utp->freq) ||
 910                         __put_user(txc.maxerror, &utp->maxerror) ||
 911                         __put_user(txc.esterror, &utp->esterror) ||
 912                         __put_user(txc.status, &utp->status) ||
 913                         __put_user(txc.constant, &utp->constant) ||
 914                         __put_user(txc.precision, &utp->precision) ||
 915                         __put_user(txc.tolerance, &utp->tolerance) ||
 916                         __put_user(txc.time.tv_sec, &utp->time.tv_sec) ||
 917                         __put_user(txc.time.tv_usec, &utp->time.tv_usec) ||
 918                         __put_user(txc.tick, &utp->tick) ||
 919                         __put_user(txc.ppsfreq, &utp->ppsfreq) ||
 920                         __put_user(txc.jitter, &utp->jitter) ||
 921                         __put_user(txc.shift, &utp->shift) ||
 922                         __put_user(txc.stabil, &utp->stabil) ||
 923                         __put_user(txc.jitcnt, &utp->jitcnt) ||
 924                         __put_user(txc.calcnt, &utp->calcnt) ||
 925                         __put_user(txc.errcnt, &utp->errcnt) ||
 926                         __put_user(txc.stbcnt, &utp->stbcnt))
 927                 ret = -EFAULT;
 928
 929         return ret;
 930 }
 931
 932 #ifdef CONFIG_NUMA
 933 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
 934                 compat_uptr_t __user *pages32,
 935                 const int __user *nodes,
 936                 int __user *status,
 937                 int flags)
 938 {
 939         const void __user * __user *pages;
 940         int i;
 941
 942         pages = compat_alloc_user_space(nr_pages * sizeof(void *));
 943         for (i = 0; i < nr_pages; i++) {
 944                 compat_uptr_t p;
 945
 946                 if (get_user(p, pages32 + i) ||
 947                         put_user(compat_ptr(p), pages + i))
 948                         return -EFAULT;
 949         }
 950         return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
 951 }
 952 #endif