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

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