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Importing "grsecurity-3.1-3.19.2-201503201903.patch"
[people/ms/linux.git] / kernel / compat.c
CommitLineData
1da177e4
LT		 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>
63d9c273 16#include <linux/module.h>
1da177e4
LT		 17#include <linux/errno.h>
18#include <linux/time.h>
19#include <linux/signal.h>
20#include <linux/sched.h> /* for MAX_SCHEDULE_TIMEOUT */
1da177e4
LT		 21#include <linux/syscalls.h>
22#include <linux/unistd.h>
23#include <linux/security.h>
3158e941 24#include <linux/timex.h>
6e5fdeed 25#include <linux/export.h>
1b2db9fb 26#include <linux/migrate.h>
1711ef38 27#include <linux/posix-timers.h>
f06febc9 28#include <linux/times.h>
e3d5a27d 29#include <linux/ptrace.h>
5a0e3ad6 30#include <linux/gfp.h>
1da177e4
LT		 31
32#include <asm/uaccess.h>
1da177e4 33
65f5d80b
RC		 34static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
35{
36 memset(txc, 0, sizeof(struct timex));
37
38 if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
39 __get_user(txc->modes, &utp->modes) ||
40 __get_user(txc->offset, &utp->offset) ||
41 __get_user(txc->freq, &utp->freq) ||
42 __get_user(txc->maxerror, &utp->maxerror) ||
43 __get_user(txc->esterror, &utp->esterror) ||
44 __get_user(txc->status, &utp->status) ||
45 __get_user(txc->constant, &utp->constant) ||
46 __get_user(txc->precision, &utp->precision) ||
47 __get_user(txc->tolerance, &utp->tolerance) ||
48 __get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
49 __get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
50 __get_user(txc->tick, &utp->tick) ||
51 __get_user(txc->ppsfreq, &utp->ppsfreq) ||
52 __get_user(txc->jitter, &utp->jitter) ||
53 __get_user(txc->shift, &utp->shift) ||
54 __get_user(txc->stabil, &utp->stabil) ||
55 __get_user(txc->jitcnt, &utp->jitcnt) ||
56 __get_user(txc->calcnt, &utp->calcnt) ||
57 __get_user(txc->errcnt, &utp->errcnt) ||
58 __get_user(txc->stbcnt, &utp->stbcnt))
59 return -EFAULT;
60
61 return 0;
62}
63
64static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
65{
66 if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
67 __put_user(txc->modes, &utp->modes) ||
68 __put_user(txc->offset, &utp->offset) ||
69 __put_user(txc->freq, &utp->freq) ||
70 __put_user(txc->maxerror, &utp->maxerror) ||
71 __put_user(txc->esterror, &utp->esterror) ||
72 __put_user(txc->status, &utp->status) ||
73 __put_user(txc->constant, &utp->constant) ||
74 __put_user(txc->precision, &utp->precision) ||
75 __put_user(txc->tolerance, &utp->tolerance) ||
76 __put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
77 __put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
78 __put_user(txc->tick, &utp->tick) ||
79 __put_user(txc->ppsfreq, &utp->ppsfreq) ||
80 __put_user(txc->jitter, &utp->jitter) ||
81 __put_user(txc->shift, &utp->shift) ||
82 __put_user(txc->stabil, &utp->stabil) ||
83 __put_user(txc->jitcnt, &utp->jitcnt) ||
84 __put_user(txc->calcnt, &utp->calcnt) ||
85 __put_user(txc->errcnt, &utp->errcnt) ||
86 __put_user(txc->stbcnt, &utp->stbcnt) ||
87 __put_user(txc->tai, &utp->tai))
88 return -EFAULT;
89 return 0;
90}
91
62a6fa97
HC		 92COMPAT_SYSCALL_DEFINE2(gettimeofday, struct compat_timeval __user *, tv,
93 struct timezone __user *, tz)
b418da16
CH		 94{
95 if (tv) {
96 struct timeval ktv;
97 do_gettimeofday(&ktv);
81993e81 98 if (compat_put_timeval(&ktv, tv))
b418da16
CH		 99 return -EFAULT;
100 }
101 if (tz) {
102 if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
103 return -EFAULT;
104 }
105
106 return 0;
107}
108
62a6fa97
HC		 109COMPAT_SYSCALL_DEFINE2(settimeofday, struct compat_timeval __user *, tv,
110 struct timezone __user *, tz)
b418da16 111{
81993e81
PA		 112 struct timeval user_tv;
113 struct timespec new_ts;
114 struct timezone new_tz;
b418da16
CH		 115
116 if (tv) {
81993e81 117 if (compat_get_timeval(&user_tv, tv))
b418da16 118 return -EFAULT;
81993e81
PA		 119 new_ts.tv_sec = user_tv.tv_sec;
120 new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
b418da16
CH		 121 }
122 if (tz) {
81993e81 123 if (copy_from_user(&new_tz, tz, sizeof(*tz)))
b418da16
CH		 124 return -EFAULT;
125 }
126
81993e81 127 return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
b418da16
CH		 128}
129
81993e81 130static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
6684ba20
PA		 131{
132 return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
133 __get_user(tv->tv_sec, &ctv->tv_sec) ||
134 __get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
135}
6684ba20 136
81993e81 137static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
6684ba20
PA		 138{
139 return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
140 __put_user(tv->tv_sec, &ctv->tv_sec) ||
141 __put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
142}
6684ba20 143
81993e81 144static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
1da177e4
LT		 145{
146 return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
147 __get_user(ts->tv_sec, &cts->tv_sec) ||
148 __get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
149}
150
81993e81 151static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
1da177e4
LT		 152{
153 return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
154 __put_user(ts->tv_sec, &cts->tv_sec) ||
155 __put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
156}
157
6684ba20
PA		 158int compat_get_timeval(struct timeval *tv, const void __user *utv)
159{
160 if (COMPAT_USE_64BIT_TIME)
6516a466 161 return copy_from_user(tv, utv, sizeof(*tv)) ? -EFAULT : 0;
6684ba20 162 else
81993e81 163 return __compat_get_timeval(tv, utv);
6684ba20
PA		 164}
165EXPORT_SYMBOL_GPL(compat_get_timeval);
166
167int compat_put_timeval(const struct timeval *tv, void __user *utv)
168{
169 if (COMPAT_USE_64BIT_TIME)
6516a466 170 return copy_to_user(utv, tv, sizeof(*tv)) ? -EFAULT : 0;
6684ba20 171 else
81993e81 172 return __compat_put_timeval(tv, utv);
6684ba20
PA		 173}
174EXPORT_SYMBOL_GPL(compat_put_timeval);
175
176int compat_get_timespec(struct timespec *ts, const void __user *uts)
177{
178 if (COMPAT_USE_64BIT_TIME)
6516a466 179 return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0;
6684ba20 180 else
81993e81 181 return __compat_get_timespec(ts, uts);
6684ba20
PA		 182}
183EXPORT_SYMBOL_GPL(compat_get_timespec);
184
185int compat_put_timespec(const struct timespec *ts, void __user *uts)
186{
187 if (COMPAT_USE_64BIT_TIME)
6516a466 188 return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0;
6684ba20 189 else
81993e81 190 return __compat_put_timespec(ts, uts);
6684ba20
PA		 191}
192EXPORT_SYMBOL_GPL(compat_put_timespec);
193
81993e81
PA		 194int compat_convert_timespec(struct timespec __user **kts,
195 const void __user *cts)
196{
197 struct timespec ts;
198 struct timespec __user *uts;
199
200 if (!cts || COMPAT_USE_64BIT_TIME) {
201 *kts = (struct timespec __user *)cts;
202 return 0;
203 }
204
205 uts = compat_alloc_user_space(sizeof(ts));
206 if (!uts)
207 return -EFAULT;
208 if (compat_get_timespec(&ts, cts))
209 return -EFAULT;
210 if (copy_to_user(uts, &ts, sizeof(ts)))
211 return -EFAULT;
212
213 *kts = uts;
214 return 0;
215}
216
41652937
ON		 217static long compat_nanosleep_restart(struct restart_block *restart)
218{
219 struct compat_timespec __user *rmtp;
220 struct timespec rmt;
221 mm_segment_t oldfs;
222 long ret;
223
63d9c273 224 restart->nanosleep.rmtp = (struct timespec __force_user *) &rmt;
41652937
ON		 225 oldfs = get_fs();
226 set_fs(KERNEL_DS);
227 ret = hrtimer_nanosleep_restart(restart);
228 set_fs(oldfs);
229
849151dd 230 if (ret == -ERESTART_RESTARTBLOCK) {
029a07e0 231 rmtp = restart->nanosleep.compat_rmtp;
41652937 232
81993e81 233 if (rmtp && compat_put_timespec(&rmt, rmtp))
41652937
ON		 234 return -EFAULT;
235 }
236
237 return ret;
238}
239
62a6fa97
HC		 240COMPAT_SYSCALL_DEFINE2(nanosleep, struct compat_timespec __user *, rqtp,
241 struct compat_timespec __user *, rmtp)
1da177e4 242{
c70878b4 243 struct timespec tu, rmt;
41652937 244 mm_segment_t oldfs;
c70878b4 245 long ret;
1da177e4 246
81993e81 247 if (compat_get_timespec(&tu, rqtp))
1da177e4
LT		 248 return -EFAULT;
249
c70878b4 250 if (!timespec_valid(&tu))
1da177e4
LT		 251 return -EINVAL;
252
41652937
ON		 253 oldfs = get_fs();
254 set_fs(KERNEL_DS);
255 ret = hrtimer_nanosleep(&tu,
63d9c273 256 rmtp ? (struct timespec __force_user *)&rmt : NULL,
41652937
ON		 257 HRTIMER_MODE_REL, CLOCK_MONOTONIC);
258 set_fs(oldfs);
259
849151dd
TG		 260 /*
261 * hrtimer_nanosleep() can only return 0 or
262 * -ERESTART_RESTARTBLOCK here because:
263 *
264 * - we call it with HRTIMER_MODE_REL and therefor exclude the
265 * -ERESTARTNOHAND return path.
266 *
267 * - we supply the rmtp argument from the task stack (due to
268 * the necessary compat conversion. So the update cannot
269 * fail, which excludes the -EFAULT return path as well. If
270 * it fails nevertheless we have a bigger problem and wont
271 * reach this place anymore.
272 *
273 * - if the return value is 0, we do not have to update rmtp
274 * because there is no remaining time.
275 *
276 * We check for -ERESTART_RESTARTBLOCK nevertheless if the
277 * core implementation decides to return random nonsense.
278 */
279 if (ret == -ERESTART_RESTARTBLOCK) {
41652937
ON		 280 struct restart_block *restart
281 = &current_thread_info()->restart_block;
282
283 restart->fn = compat_nanosleep_restart;
029a07e0 284 restart->nanosleep.compat_rmtp = rmtp;
1da177e4 285
81993e81 286 if (rmtp && compat_put_timespec(&rmt, rmtp))
1da177e4
LT		 287 return -EFAULT;
288 }
c70878b4 289 return ret;
1da177e4
LT		 290}
291
292static inline long get_compat_itimerval(struct itimerval *o,
293 struct compat_itimerval __user *i)
294{
295 return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
296 (__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
297 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
298 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
299 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
300}
301
302static inline long put_compat_itimerval(struct compat_itimerval __user *o,
303 struct itimerval *i)
304{
305 return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
306 (__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
307 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
308 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
309 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
310}
311
37784074
AV		 312COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
313 struct compat_itimerval __user *, it)
1da177e4
LT		 314{
315 struct itimerval kit;
316 int error;
317
318 error = do_getitimer(which, &kit);
319 if (!error && put_compat_itimerval(it, &kit))
320 error = -EFAULT;
321 return error;
322}
323
37784074
AV		 324COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
325 struct compat_itimerval __user *, in,
326 struct compat_itimerval __user *, out)
1da177e4
LT		 327{
328 struct itimerval kin, kout;
329 int error;
330
331 if (in) {
332 if (get_compat_itimerval(&kin, in))
333 return -EFAULT;
334 } else
335 memset(&kin, 0, sizeof(kin));
336
337 error = do_setitimer(which, &kin, out ? &kout : NULL);
338 if (error || !out)
339 return error;
340 if (put_compat_itimerval(out, &kout))
341 return -EFAULT;
342 return 0;
343}
344
f06febc9
FM		 345static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
346{
347 return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
348}
349
62a6fa97 350COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
1da177e4 351{
1da177e4 352 if (tbuf) {
f06febc9 353 struct tms tms;
1da177e4 354 struct compat_tms tmp;
f06febc9
FM		 355
356 do_sys_times(&tms);
357 /* Convert our struct tms to the compat version. */
358 tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
359 tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
360 tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
361 tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
1da177e4
LT		 362 if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
363 return -EFAULT;
364 }
e3d5a27d 365 force_successful_syscall_return();
1da177e4
LT		 366 return compat_jiffies_to_clock_t(jiffies);
367}
368
be84cb43
CM		 369#ifdef __ARCH_WANT_SYS_SIGPENDING
370
1da177e4
LT		 371/*
372 * Assumption: old_sigset_t and compat_old_sigset_t are both
373 * types that can be passed to put_user()/get_user().
374 */
375
62a6fa97 376COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
1da177e4
LT		 377{
378 old_sigset_t s;
379 long ret;
380 mm_segment_t old_fs = get_fs();
381
382 set_fs(KERNEL_DS);
63d9c273 383 ret = sys_sigpending((old_sigset_t __force_user *) &s);
1da177e4
LT		 384 set_fs(old_fs);
385 if (ret == 0)
386 ret = put_user(s, set);
387 return ret;
388}
389
be84cb43
CM		 390#endif
391
392#ifdef __ARCH_WANT_SYS_SIGPROCMASK
393
b7dafa0e
JK		 394/*
395 * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
396 * blocked set of signals to the supplied signal set
397 */
398static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
1da177e4 399{
b7dafa0e
JK		 400 memcpy(blocked->sig, &set, sizeof(set));
401}
1da177e4 402
5cf22100
AV		 403COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
404 compat_old_sigset_t __user *, nset,
405 compat_old_sigset_t __user *, oset)
b7dafa0e
JK		 406{
407 old_sigset_t old_set, new_set;
408 sigset_t new_blocked;
409
410 old_set = current->blocked.sig[0];
411
412 if (nset) {
413 if (get_user(new_set, nset))
414 return -EFAULT;
415 new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
416
417 new_blocked = current->blocked;
418
419 switch (how) {
420 case SIG_BLOCK:
421 sigaddsetmask(&new_blocked, new_set);
422 break;
423 case SIG_UNBLOCK:
424 sigdelsetmask(&new_blocked, new_set);
425 break;
426 case SIG_SETMASK:
427 compat_sig_setmask(&new_blocked, new_set);
428 break;
429 default:
430 return -EINVAL;
431 }
432
433 set_current_blocked(&new_blocked);
434 }
435
436 if (oset) {
437 if (put_user(old_set, oset))
438 return -EFAULT;
439 }
440
441 return 0;
1da177e4
LT		 442}
443
be84cb43
CM		 444#endif
445
62a6fa97
HC		 446COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
447 struct compat_rlimit __user *, rlim)
1da177e4
LT		 448{
449 struct rlimit r;
1da177e4
LT		 450
451 if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
452 __get_user(r.rlim_cur, &rlim->rlim_cur) ||
453 __get_user(r.rlim_max, &rlim->rlim_max))
454 return -EFAULT;
455
456 if (r.rlim_cur == COMPAT_RLIM_INFINITY)
457 r.rlim_cur = RLIM_INFINITY;
458 if (r.rlim_max == COMPAT_RLIM_INFINITY)
459 r.rlim_max = RLIM_INFINITY;
b9518345 460 return do_prlimit(current, resource, &r, NULL);
1da177e4
LT		 461}
462
463#ifdef COMPAT_RLIM_OLD_INFINITY
464
62a6fa97
HC		 465COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
466 struct compat_rlimit __user *, rlim)
1da177e4
LT		 467{
468 struct rlimit r;
469 int ret;
470 mm_segment_t old_fs = get_fs();
471
472 set_fs(KERNEL_DS);
63d9c273 473 ret = sys_old_getrlimit(resource, (struct rlimit __force_user *)&r);
1da177e4
LT		 474 set_fs(old_fs);
475
476 if (!ret) {
477 if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
478 r.rlim_cur = COMPAT_RLIM_INFINITY;
479 if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
480 r.rlim_max = COMPAT_RLIM_INFINITY;
481
482 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
483 __put_user(r.rlim_cur, &rlim->rlim_cur) ||
484 __put_user(r.rlim_max, &rlim->rlim_max))
485 return -EFAULT;
486 }
487 return ret;
488}
489
490#endif
491
62a6fa97
HC		 492COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
493 struct compat_rlimit __user *, rlim)
1da177e4
LT		 494{
495 struct rlimit r;
496 int ret;
1da177e4 497
b9518345 498 ret = do_prlimit(current, resource, NULL, &r);
1da177e4
LT		 499 if (!ret) {
500 if (r.rlim_cur > COMPAT_RLIM_INFINITY)
501 r.rlim_cur = COMPAT_RLIM_INFINITY;
502 if (r.rlim_max > COMPAT_RLIM_INFINITY)
503 r.rlim_max = COMPAT_RLIM_INFINITY;
504
505 if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
506 __put_user(r.rlim_cur, &rlim->rlim_cur) ||
507 __put_user(r.rlim_max, &rlim->rlim_max))
508 return -EFAULT;
509 }
510 return ret;
511}
512
513int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
514{
515 if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
516 __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
517 __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
518 __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
519 __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
520 __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
521 __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
522 __put_user(r->ru_idrss, &ru->ru_idrss) ||
523 __put_user(r->ru_isrss, &ru->ru_isrss) ||
524 __put_user(r->ru_minflt, &ru->ru_minflt) ||
525 __put_user(r->ru_majflt, &ru->ru_majflt) ||
526 __put_user(r->ru_nswap, &ru->ru_nswap) ||
527 __put_user(r->ru_inblock, &ru->ru_inblock) ||
528 __put_user(r->ru_oublock, &ru->ru_oublock) ||
529 __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
530 __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
531 __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
532 __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
533 __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
534 return -EFAULT;
535 return 0;
536}
537
8d9807b1
AV		 538COMPAT_SYSCALL_DEFINE4(wait4,
539 compat_pid_t, pid,
540 compat_uint_t __user *, stat_addr,
541 int, options,
542 struct compat_rusage __user *, ru)
1da177e4
LT		 543{
544 if (!ru) {
545 return sys_wait4(pid, stat_addr, options, NULL);
546 } else {
547 struct rusage r;
548 int ret;
549 unsigned int status;
550 mm_segment_t old_fs = get_fs();
551
552 set_fs (KERNEL_DS);
553 ret = sys_wait4(pid,
554 (stat_addr ?
63d9c273
MT		 555 (unsigned int __force_user *) &status : NULL),
556 options, (struct rusage __force_user *) &r);
1da177e4
LT		 557 set_fs (old_fs);
558
559 if (ret > 0) {
560 if (put_compat_rusage(&r, ru))
561 return -EFAULT;
562 if (stat_addr && put_user(status, stat_addr))
563 return -EFAULT;
564 }
565 return ret;
566 }
567}
568
8d9807b1
AV		 569COMPAT_SYSCALL_DEFINE5(waitid,
570 int, which, compat_pid_t, pid,
571 struct compat_siginfo __user *, uinfo, int, options,
572 struct compat_rusage __user *, uru)
1da177e4
LT		 573{
574 siginfo_t info;
575 struct rusage ru;
576 long ret;
577 mm_segment_t old_fs = get_fs();
578
579 memset(&info, 0, sizeof(info));
580
581 set_fs(KERNEL_DS);
63d9c273
MT		 582 ret = sys_waitid(which, pid, (siginfo_t __force_user *)&info, options,
583 uru ? (struct rusage __force_user *)&ru : NULL);
1da177e4
LT		 584 set_fs(old_fs);
585
586 if ((ret < 0) || (info.si_signo == 0))
587 return ret;
588
589 if (uru) {
a566c288
AV		 590 /* sys_waitid() overwrites everything in ru */
591 if (COMPAT_USE_64BIT_TIME)
592 ret = copy_to_user(uru, &ru, sizeof(ru));
593 else
594 ret = put_compat_rusage(&ru, uru);
1da177e4 595 if (ret)
bffea77c 596 return -EFAULT;
1da177e4
LT		 597 }
598
599 BUG_ON(info.si_code & __SI_MASK);
600 info.si_code |= __SI_CHLD;
601 return copy_siginfo_to_user32(uinfo, &info);
602}
603
604static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
a45185d2 605 unsigned len, struct cpumask *new_mask)
1da177e4
LT		 606{
607 unsigned long *k;
608
a45185d2
RR		 609 if (len < cpumask_size())
610 memset(new_mask, 0, cpumask_size());
611 else if (len > cpumask_size())
612 len = cpumask_size();
1da177e4 613
a45185d2 614 k = cpumask_bits(new_mask);
1da177e4
LT		 615 return compat_get_bitmap(k, user_mask_ptr, len * 8);
616}
617
62a6fa97
HC		 618COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid,
619 unsigned int, len,
620 compat_ulong_t __user *, user_mask_ptr)
1da177e4 621{
a45185d2 622 cpumask_var_t new_mask;
1da177e4
LT		 623 int retval;
624
a45185d2
RR		 625 if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
626 return -ENOMEM;
627
628 retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
1da177e4 629 if (retval)
a45185d2 630 goto out;
1da177e4 631
a45185d2
RR		 632 retval = sched_setaffinity(pid, new_mask);
633out:
634 free_cpumask_var(new_mask);
635 return retval;
1da177e4
LT		 636}
637
62a6fa97
HC		 638COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t, pid, unsigned int, len,
639 compat_ulong_t __user *, user_mask_ptr)
1da177e4
LT		 640{
641 int ret;
a45185d2 642 cpumask_var_t mask;
1da177e4 643
fa9dc265
KM		 644 if ((len * BITS_PER_BYTE) < nr_cpu_ids)
645 return -EINVAL;
646 if (len & (sizeof(compat_ulong_t)-1))
1da177e4
LT		 647 return -EINVAL;
648
a45185d2
RR		 649 if (!alloc_cpumask_var(&mask, GFP_KERNEL))
650 return -ENOMEM;
651
652 ret = sched_getaffinity(pid, mask);
fa9dc265
KM		 653 if (ret == 0) {
654 size_t retlen = min_t(size_t, len, cpumask_size());
1da177e4 655
fa9dc265
KM		 656 if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
657 ret = -EFAULT;
658 else
659 ret = retlen;
660 }
a45185d2 661 free_cpumask_var(mask);
fa9dc265 662
a45185d2 663 return ret;
1da177e4
LT		 664}
665
83f5d126
DL		 666int get_compat_itimerspec(struct itimerspec *dst,
667 const struct compat_itimerspec __user *src)
bd3a8492 668{
81993e81
PA		 669 if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
670 __compat_get_timespec(&dst->it_value, &src->it_value))
1da177e4
LT		 671 return -EFAULT;
672 return 0;
bd3a8492 673}
1da177e4 674
83f5d126
DL		 675int put_compat_itimerspec(struct compat_itimerspec __user *dst,
676 const struct itimerspec *src)
bd3a8492 677{
81993e81
PA		 678 if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
679 __compat_put_timespec(&src->it_value, &dst->it_value))
1da177e4
LT		 680 return -EFAULT;
681 return 0;
bd3a8492 682}
1da177e4 683
62a6fa97
HC		 684COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
685 struct compat_sigevent __user *, timer_event_spec,
686 timer_t __user *, created_timer_id)
3a0f69d5
CH		 687{
688 struct sigevent __user *event = NULL;
689
690 if (timer_event_spec) {
691 struct sigevent kevent;
692
693 event = compat_alloc_user_space(sizeof(*event));
694 if (get_compat_sigevent(&kevent, timer_event_spec) ||
695 copy_to_user(event, &kevent, sizeof(*event)))
696 return -EFAULT;
697 }
698
699 return sys_timer_create(which_clock, event, created_timer_id);
700}
701
62a6fa97
HC		 702COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
703 struct compat_itimerspec __user *, new,
704 struct compat_itimerspec __user *, old)
bd3a8492 705{
1da177e4
LT		 706 long err;
707 mm_segment_t oldfs;
708 struct itimerspec newts, oldts;
709
710 if (!new)
711 return -EINVAL;
712 if (get_compat_itimerspec(&newts, new))
bd3a8492 713 return -EFAULT;
1da177e4
LT		 714 oldfs = get_fs();
715 set_fs(KERNEL_DS);
716 err = sys_timer_settime(timer_id, flags,
63d9c273
MT		 717 (struct itimerspec __force_user *) &newts,
718 (struct itimerspec __force_user *) &oldts);
bd3a8492 719 set_fs(oldfs);
1da177e4
LT		 720 if (!err && old && put_compat_itimerspec(old, &oldts))
721 return -EFAULT;
722 return err;
bd3a8492 723}
1da177e4 724
62a6fa97
HC		 725COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
726 struct compat_itimerspec __user *, setting)
bd3a8492 727{
1da177e4
LT		 728 long err;
729 mm_segment_t oldfs;
bd3a8492 730 struct itimerspec ts;
1da177e4
LT		 731
732 oldfs = get_fs();
733 set_fs(KERNEL_DS);
734 err = sys_timer_gettime(timer_id,
63d9c273 735 (struct itimerspec __force_user *) &ts);
bd3a8492 736 set_fs(oldfs);
1da177e4
LT		 737 if (!err && put_compat_itimerspec(setting, &ts))
738 return -EFAULT;
739 return err;
bd3a8492 740}
1da177e4 741
62a6fa97
HC		 742COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
743 struct compat_timespec __user *, tp)
1da177e4
LT		 744{
745 long err;
746 mm_segment_t oldfs;
bd3a8492 747 struct timespec ts;
1da177e4 748
81993e81 749 if (compat_get_timespec(&ts, tp))
bd3a8492 750 return -EFAULT;
1da177e4 751 oldfs = get_fs();
bd3a8492 752 set_fs(KERNEL_DS);
1da177e4 753 err = sys_clock_settime(which_clock,
63d9c273 754 (struct timespec __force_user *) &ts);
1da177e4
LT		 755 set_fs(oldfs);
756 return err;
bd3a8492 757}
1da177e4 758
62a6fa97
HC		 759COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
760 struct compat_timespec __user *, tp)
1da177e4
LT		 761{
762 long err;
763 mm_segment_t oldfs;
bd3a8492 764 struct timespec ts;
1da177e4
LT		 765
766 oldfs = get_fs();
767 set_fs(KERNEL_DS);
768 err = sys_clock_gettime(which_clock,
63d9c273 769 (struct timespec __force_user *) &ts);
1da177e4 770 set_fs(oldfs);
81993e81 771 if (!err && compat_put_timespec(&ts, tp))
bd3a8492 772 return -EFAULT;
1da177e4 773 return err;
bd3a8492 774}
1da177e4 775
62a6fa97
HC		 776COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
777 struct compat_timex __user *, utp)
f1f1d5eb
RC		 778{
779 struct timex txc;
780 mm_segment_t oldfs;
781 int err, ret;
782
783 err = compat_get_timex(&txc, utp);
784 if (err)
785 return err;
786
787 oldfs = get_fs();
788 set_fs(KERNEL_DS);
63d9c273 789 ret = sys_clock_adjtime(which_clock, (struct timex __force_user *) &txc);
f1f1d5eb
RC		 790 set_fs(oldfs);
791
792 err = compat_put_timex(utp, &txc);
793 if (err)
794 return err;
795
796 return ret;
797}
798
62a6fa97
HC		 799COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
800 struct compat_timespec __user *, tp)
1da177e4
LT		 801{
802 long err;
803 mm_segment_t oldfs;
bd3a8492 804 struct timespec ts;
1da177e4
LT		 805
806 oldfs = get_fs();
807 set_fs(KERNEL_DS);
808 err = sys_clock_getres(which_clock,
63d9c273 809 (struct timespec __force_user *) &ts);
1da177e4 810 set_fs(oldfs);
81993e81 811 if (!err && tp && compat_put_timespec(&ts, tp))
bd3a8492 812 return -EFAULT;
1da177e4 813 return err;
bd3a8492 814}
1da177e4 815
1711ef38
TA		 816static long compat_clock_nanosleep_restart(struct restart_block *restart)
817{
818 long err;
819 mm_segment_t oldfs;
820 struct timespec tu;
dce44e03 821 struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp;
1711ef38 822
63d9c273 823 restart->nanosleep.rmtp = (struct timespec __force_user *) &tu;
1711ef38
TA		 824 oldfs = get_fs();
825 set_fs(KERNEL_DS);
826 err = clock_nanosleep_restart(restart);
827 set_fs(oldfs);
828
829 if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
81993e81 830 compat_put_timespec(&tu, rmtp))
1711ef38
TA		 831 return -EFAULT;
832
833 if (err == -ERESTART_RESTARTBLOCK) {
834 restart->fn = compat_clock_nanosleep_restart;
029a07e0 835 restart->nanosleep.compat_rmtp = rmtp;
1711ef38
TA		 836 }
837 return err;
838}
839
62a6fa97
HC		 840COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
841 struct compat_timespec __user *, rqtp,
842 struct compat_timespec __user *, rmtp)
1da177e4
LT		 843{
844 long err;
845 mm_segment_t oldfs;
bd3a8492 846 struct timespec in, out;
1711ef38 847 struct restart_block *restart;
1da177e4 848
81993e81 849 if (compat_get_timespec(&in, rqtp))
1da177e4
LT		 850 return -EFAULT;
851
852 oldfs = get_fs();
853 set_fs(KERNEL_DS);
854 err = sys_clock_nanosleep(which_clock, flags,
63d9c273
MT		 855 (struct timespec __force_user *) &in,
856 (struct timespec __force_user *) &out);
1da177e4 857 set_fs(oldfs);
1711ef38 858
1da177e4 859 if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
81993e81 860 compat_put_timespec(&out, rmtp))
1da177e4 861 return -EFAULT;
1711ef38
TA		 862
863 if (err == -ERESTART_RESTARTBLOCK) {
864 restart = &current_thread_info()->restart_block;
865 restart->fn = compat_clock_nanosleep_restart;
029a07e0 866 restart->nanosleep.compat_rmtp = rmtp;
1711ef38 867 }
bd3a8492
DW		 868 return err;
869}
1da177e4
LT		 870
871/*
872 * We currently only need the following fields from the sigevent
873 * structure: sigev_value, sigev_signo, sig_notify and (sometimes
874 * sigev_notify_thread_id). The others are handled in user mode.
875 * We also assume that copying sigev_value.sival_int is sufficient
876 * to keep all the bits of sigev_value.sival_ptr intact.
877 */
878int get_compat_sigevent(struct sigevent *event,
879 const struct compat_sigevent __user *u_event)
880{
51410d3c 881 memset(event, 0, sizeof(*event));
1da177e4
LT		 882 return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
883 __get_user(event->sigev_value.sival_int,
884 &u_event->sigev_value.sival_int) ||
885 __get_user(event->sigev_signo, &u_event->sigev_signo) ||
886 __get_user(event->sigev_notify, &u_event->sigev_notify) ||
887 __get_user(event->sigev_notify_thread_id,
888 &u_event->sigev_notify_thread_id))
889 ? -EFAULT : 0;
890}
891
5fa3839a 892long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
1da177e4
LT		 893 unsigned long bitmap_size)
894{
895 int i, j;
896 unsigned long m;
897 compat_ulong_t um;
898 unsigned long nr_compat_longs;
899
900 /* align bitmap up to nearest compat_long_t boundary */
901 bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
902
903 if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
904 return -EFAULT;
905
906 nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
907
908 for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
909 m = 0;
910
911 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
912 /*
913 * We dont want to read past the end of the userspace
914 * bitmap. We must however ensure the end of the
915 * kernel bitmap is zeroed.
916 */
917 if (nr_compat_longs-- > 0) {
918 if (__get_user(um, umask))
919 return -EFAULT;
920 } else {
921 um = 0;
922 }
923
924 umask++;
925 m |= (long)um << (j * BITS_PER_COMPAT_LONG);
926 }
927 *mask++ = m;
928 }
929
930 return 0;
931}
932
933long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
934 unsigned long bitmap_size)
935{
936 int i, j;
937 unsigned long m;
938 compat_ulong_t um;
939 unsigned long nr_compat_longs;
940
941 /* align bitmap up to nearest compat_long_t boundary */
942 bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
943
944 if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
945 return -EFAULT;
946
947 nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
948
949 for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
950 m = *mask++;
951
952 for (j = 0; j < sizeof(m)/sizeof(um); j++) {
953 um = m;
954
955 /*
956 * We dont want to write past the end of the userspace
957 * bitmap.
958 */
959 if (nr_compat_longs-- > 0) {
960 if (__put_user(um, umask))
961 return -EFAULT;
962 }
963
964 umask++;
965 m >>= 4*sizeof(um);
966 m >>= 4*sizeof(um);
967 }
968 }
969
970 return 0;
971}
972
973void
322a56cb 974sigset_from_compat(sigset_t *set, const compat_sigset_t *compat)
1da177e4
LT		 975{
976 switch (_NSIG_WORDS) {
1da177e4
LT		 977 case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
978 case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
979 case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
980 case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
1da177e4
LT		 981 }
982}
1dda606c 983EXPORT_SYMBOL_GPL(sigset_from_compat);
1da177e4 984
322a56cb
AV		 985void
986sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
987{
988 switch (_NSIG_WORDS) {
989 case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
990 case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
991 case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
992 case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
993 }
994}
995
28d27f2d
AV		 996COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
997 struct compat_siginfo __user *, uinfo,
998 struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
1da177e4
LT		 999{
1000 compat_sigset_t s32;
1001 sigset_t s;
1da177e4
LT		 1002 struct timespec t;
1003 siginfo_t info;
943df148 1004 long ret;
1da177e4
LT		 1005
1006 if (sigsetsize != sizeof(sigset_t))
1007 return -EINVAL;
1008
1009 if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
1010 return -EFAULT;
1011 sigset_from_compat(&s, &s32);
1da177e4
LT		 1012
1013 if (uts) {
b2ddedcd 1014 if (compat_get_timespec(&t, uts))
1da177e4 1015 return -EFAULT;
1da177e4
LT		 1016 }
1017
943df148 1018 ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1da177e4 1019
943df148
ON		 1020 if (ret > 0 && uinfo) {
1021 if (copy_siginfo_to_user32(uinfo, &info))
1022 ret = -EFAULT;
1da177e4 1023 }
943df148 1024
1da177e4 1025 return ret;
62ab4505
TG		 1026}
1027
1da177e4
LT		 1028#ifdef __ARCH_WANT_COMPAT_SYS_TIME
1029
1030/* compat_time_t is a 32 bit "long" and needs to get converted. */
1031
62a6fa97 1032COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
1da177e4
LT		 1033{
1034 compat_time_t i;
1035 struct timeval tv;
1036
1037 do_gettimeofday(&tv);
1038 i = tv.tv_sec;
1039
1040 if (tloc) {
1041 if (put_user(i,tloc))
e3d5a27d 1042 return -EFAULT;
1da177e4 1043 }
e3d5a27d 1044 force_successful_syscall_return();
1da177e4
LT		 1045 return i;
1046}
1047
62a6fa97 1048COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
1da177e4
LT		 1049{
1050 struct timespec tv;
1051 int err;
1052
1053 if (get_user(tv.tv_sec, tptr))
1054 return -EFAULT;
1055
1056 tv.tv_nsec = 0;
1057
1058 err = security_settime(&tv, NULL);
1059 if (err)
1060 return err;
1061
1062 do_settimeofday(&tv);
1063 return 0;
1064}
1065
1066#endif /* __ARCH_WANT_COMPAT_SYS_TIME */
150256d8 1067
62a6fa97 1068COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)
3158e941
SR		 1069{
1070 struct timex txc;
65f5d80b 1071 int err, ret;
3158e941 1072
65f5d80b
RC		 1073 err = compat_get_timex(&txc, utp);
1074 if (err)
1075 return err;
3158e941
SR		 1076
1077 ret = do_adjtimex(&txc);
1078
65f5d80b
RC		 1079 err = compat_put_timex(utp, &txc);
1080 if (err)
1081 return err;
3158e941
SR		 1082
1083 return ret;
1084}
1b2db9fb
CL		 1085
1086#ifdef CONFIG_NUMA
2f2728f6
HC		 1087COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
1088 compat_uptr_t __user *, pages32,
1089 const int __user *, nodes,
1090 int __user *, status,
1091 int, flags)
1b2db9fb
CL		 1092{
1093 const void __user * __user *pages;
1094 int i;
1095
1096 pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1097 for (i = 0; i < nr_pages; i++) {
1098 compat_uptr_t p;
1099
9216dfad 1100 if (get_user(p, pages32 + i) ||
1b2db9fb
CL		 1101 put_user(compat_ptr(p), pages + i))
1102 return -EFAULT;
1103 }
1104 return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1105}
3fd59397 1106
62a6fa97
HC		 1107COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
1108 compat_ulong_t, maxnode,
1109 const compat_ulong_t __user *, old_nodes,
1110 const compat_ulong_t __user *, new_nodes)
3fd59397
SR		 1111{
1112 unsigned long __user *old = NULL;
1113 unsigned long __user *new = NULL;
1114 nodemask_t tmp_mask;
1115 unsigned long nr_bits;
1116 unsigned long size;
1117
1118 nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1119 size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1120 if (old_nodes) {
1121 if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1122 return -EFAULT;
1123 old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1124 if (new_nodes)
1125 new = old + size / sizeof(unsigned long);
1126 if (copy_to_user(old, nodes_addr(tmp_mask), size))
1127 return -EFAULT;
1128 }
1129 if (new_nodes) {
1130 if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1131 return -EFAULT;
1132 if (new == NULL)
1133 new = compat_alloc_user_space(size);
1134 if (copy_to_user(new, nodes_addr(tmp_mask), size))
1135 return -EFAULT;
1136 }
1137 return sys_migrate_pages(pid, nr_bits + 1, old, new);
1138}
1b2db9fb 1139#endif
d4d23add 1140
6883da8c
AV		 1141COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1142 compat_pid_t, pid,
1143 struct compat_timespec __user *, interval)
0ad50c38
CM		 1144{
1145 struct timespec t;
1146 int ret;
1147 mm_segment_t old_fs = get_fs();
1148
1149 set_fs(KERNEL_DS);
63d9c273 1150 ret = sys_sched_rr_get_interval(pid, (struct timespec __force_user *)&t);
0ad50c38 1151 set_fs(old_fs);
81993e81 1152 if (compat_put_timespec(&t, interval))
0ad50c38
CM		 1153 return -EFAULT;
1154 return ret;
1155}
0ad50c38 1156
c41d68a5
PA		 1157/*
1158 * Allocate user-space memory for the duration of a single system call,
1159 * in order to marshall parameters inside a compat thunk.
1160 */
1161void __user *compat_alloc_user_space(unsigned long len)
1162{
1163 void __user *ptr;
1164
1165 /* If len would occupy more than half of the entire compat space... */
1166 if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1167 return NULL;
1168
1169 ptr = arch_compat_alloc_user_space(len);
1170
1171 if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1172 return NULL;
1173
1174 return ptr;
1175}
1176EXPORT_SYMBOL_GPL(compat_alloc_user_space);
Michael's Linux tree.