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