xref: /openbmc/linux/kernel/compat.c (revision 9ac8d3fb)
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 
28 #include <asm/uaccess.h>
29 
30 /*
31  * Note that the native side is already converted to a timespec, because
32  * that's what we want anyway.
33  */
34 static int compat_get_timeval(struct timespec *o,
35 		struct compat_timeval __user *i)
36 {
37 	long usec;
38 
39 	if (get_user(o->tv_sec, &i->tv_sec) ||
40 	    get_user(usec, &i->tv_usec))
41 		return -EFAULT;
42 	o->tv_nsec = usec * 1000;
43 	return 0;
44 }
45 
46 static int compat_put_timeval(struct compat_timeval __user *o,
47 		struct timeval *i)
48 {
49 	return (put_user(i->tv_sec, &o->tv_sec) ||
50 		put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
51 }
52 
53 asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
54 		struct timezone __user *tz)
55 {
56 	if (tv) {
57 		struct timeval ktv;
58 		do_gettimeofday(&ktv);
59 		if (compat_put_timeval(tv, &ktv))
60 			return -EFAULT;
61 	}
62 	if (tz) {
63 		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
64 			return -EFAULT;
65 	}
66 
67 	return 0;
68 }
69 
70 asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
71 		struct timezone __user *tz)
72 {
73 	struct timespec kts;
74 	struct timezone ktz;
75 
76 	if (tv) {
77 		if (compat_get_timeval(&kts, tv))
78 			return -EFAULT;
79 	}
80 	if (tz) {
81 		if (copy_from_user(&ktz, tz, sizeof(ktz)))
82 			return -EFAULT;
83 	}
84 
85 	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
86 }
87 
88 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
89 {
90 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
91 			__get_user(ts->tv_sec, &cts->tv_sec) ||
92 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
93 }
94 
95 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
96 {
97 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
98 			__put_user(ts->tv_sec, &cts->tv_sec) ||
99 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
100 }
101 
102 static long compat_nanosleep_restart(struct restart_block *restart)
103 {
104 	struct compat_timespec __user *rmtp;
105 	struct timespec rmt;
106 	mm_segment_t oldfs;
107 	long ret;
108 
109 	restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
110 	oldfs = get_fs();
111 	set_fs(KERNEL_DS);
112 	ret = hrtimer_nanosleep_restart(restart);
113 	set_fs(oldfs);
114 
115 	if (ret) {
116 		rmtp = restart->nanosleep.compat_rmtp;
117 
118 		if (rmtp && put_compat_timespec(&rmt, rmtp))
119 			return -EFAULT;
120 	}
121 
122 	return ret;
123 }
124 
125 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
126 				     struct compat_timespec __user *rmtp)
127 {
128 	struct timespec tu, rmt;
129 	mm_segment_t oldfs;
130 	long ret;
131 
132 	if (get_compat_timespec(&tu, rqtp))
133 		return -EFAULT;
134 
135 	if (!timespec_valid(&tu))
136 		return -EINVAL;
137 
138 	oldfs = get_fs();
139 	set_fs(KERNEL_DS);
140 	ret = hrtimer_nanosleep(&tu,
141 				rmtp ? (struct timespec __user *)&rmt : NULL,
142 				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
143 	set_fs(oldfs);
144 
145 	if (ret) {
146 		struct restart_block *restart
147 			= &current_thread_info()->restart_block;
148 
149 		restart->fn = compat_nanosleep_restart;
150 		restart->nanosleep.compat_rmtp = rmtp;
151 
152 		if (rmtp && put_compat_timespec(&rmt, rmtp))
153 			return -EFAULT;
154 	}
155 
156 	return ret;
157 }
158 
159 static inline long get_compat_itimerval(struct itimerval *o,
160 		struct compat_itimerval __user *i)
161 {
162 	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
163 		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
164 		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
165 		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
166 		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
167 }
168 
169 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
170 		struct itimerval *i)
171 {
172 	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
173 		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
174 		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
175 		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
176 		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
177 }
178 
179 asmlinkage long compat_sys_getitimer(int which,
180 		struct compat_itimerval __user *it)
181 {
182 	struct itimerval kit;
183 	int error;
184 
185 	error = do_getitimer(which, &kit);
186 	if (!error && put_compat_itimerval(it, &kit))
187 		error = -EFAULT;
188 	return error;
189 }
190 
191 asmlinkage long compat_sys_setitimer(int which,
192 		struct compat_itimerval __user *in,
193 		struct compat_itimerval __user *out)
194 {
195 	struct itimerval kin, kout;
196 	int error;
197 
198 	if (in) {
199 		if (get_compat_itimerval(&kin, in))
200 			return -EFAULT;
201 	} else
202 		memset(&kin, 0, sizeof(kin));
203 
204 	error = do_setitimer(which, &kin, out ? &kout : NULL);
205 	if (error || !out)
206 		return error;
207 	if (put_compat_itimerval(out, &kout))
208 		return -EFAULT;
209 	return 0;
210 }
211 
212 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
213 {
214 	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
215 }
216 
217 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
218 {
219 	if (tbuf) {
220 		struct tms tms;
221 		struct compat_tms tmp;
222 
223 		do_sys_times(&tms);
224 		/* Convert our struct tms to the compat version. */
225 		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
226 		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
227 		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
228 		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
229 		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
230 			return -EFAULT;
231 	}
232 	return compat_jiffies_to_clock_t(jiffies);
233 }
234 
235 /*
236  * Assumption: old_sigset_t and compat_old_sigset_t are both
237  * types that can be passed to put_user()/get_user().
238  */
239 
240 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
241 {
242 	old_sigset_t s;
243 	long ret;
244 	mm_segment_t old_fs = get_fs();
245 
246 	set_fs(KERNEL_DS);
247 	ret = sys_sigpending((old_sigset_t __user *) &s);
248 	set_fs(old_fs);
249 	if (ret == 0)
250 		ret = put_user(s, set);
251 	return ret;
252 }
253 
254 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
255 		compat_old_sigset_t __user *oset)
256 {
257 	old_sigset_t s;
258 	long ret;
259 	mm_segment_t old_fs;
260 
261 	if (set && get_user(s, set))
262 		return -EFAULT;
263 	old_fs = get_fs();
264 	set_fs(KERNEL_DS);
265 	ret = sys_sigprocmask(how,
266 			      set ? (old_sigset_t __user *) &s : NULL,
267 			      oset ? (old_sigset_t __user *) &s : NULL);
268 	set_fs(old_fs);
269 	if (ret == 0)
270 		if (oset)
271 			ret = put_user(s, oset);
272 	return ret;
273 }
274 
275 asmlinkage long compat_sys_setrlimit(unsigned int resource,
276 		struct compat_rlimit __user *rlim)
277 {
278 	struct rlimit r;
279 	int ret;
280 	mm_segment_t old_fs = get_fs ();
281 
282 	if (resource >= RLIM_NLIMITS)
283 		return -EINVAL;
284 
285 	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
286 	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
287 	    __get_user(r.rlim_max, &rlim->rlim_max))
288 		return -EFAULT;
289 
290 	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
291 		r.rlim_cur = RLIM_INFINITY;
292 	if (r.rlim_max == COMPAT_RLIM_INFINITY)
293 		r.rlim_max = RLIM_INFINITY;
294 	set_fs(KERNEL_DS);
295 	ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
296 	set_fs(old_fs);
297 	return ret;
298 }
299 
300 #ifdef COMPAT_RLIM_OLD_INFINITY
301 
302 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
303 		struct compat_rlimit __user *rlim)
304 {
305 	struct rlimit r;
306 	int ret;
307 	mm_segment_t old_fs = get_fs();
308 
309 	set_fs(KERNEL_DS);
310 	ret = sys_old_getrlimit(resource, &r);
311 	set_fs(old_fs);
312 
313 	if (!ret) {
314 		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
315 			r.rlim_cur = COMPAT_RLIM_INFINITY;
316 		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
317 			r.rlim_max = COMPAT_RLIM_INFINITY;
318 
319 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
320 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
321 		    __put_user(r.rlim_max, &rlim->rlim_max))
322 			return -EFAULT;
323 	}
324 	return ret;
325 }
326 
327 #endif
328 
329 asmlinkage long compat_sys_getrlimit (unsigned int resource,
330 		struct compat_rlimit __user *rlim)
331 {
332 	struct rlimit r;
333 	int ret;
334 	mm_segment_t old_fs = get_fs();
335 
336 	set_fs(KERNEL_DS);
337 	ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
338 	set_fs(old_fs);
339 	if (!ret) {
340 		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
341 			r.rlim_cur = COMPAT_RLIM_INFINITY;
342 		if (r.rlim_max > COMPAT_RLIM_INFINITY)
343 			r.rlim_max = COMPAT_RLIM_INFINITY;
344 
345 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
346 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
347 		    __put_user(r.rlim_max, &rlim->rlim_max))
348 			return -EFAULT;
349 	}
350 	return ret;
351 }
352 
353 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
354 {
355 	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
356 	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
357 	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
358 	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
359 	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
360 	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
361 	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
362 	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
363 	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
364 	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
365 	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
366 	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
367 	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
368 	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
369 	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
370 	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
371 	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
372 	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
373 	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
374 		return -EFAULT;
375 	return 0;
376 }
377 
378 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
379 {
380 	struct rusage r;
381 	int ret;
382 	mm_segment_t old_fs = get_fs();
383 
384 	set_fs(KERNEL_DS);
385 	ret = sys_getrusage(who, (struct rusage __user *) &r);
386 	set_fs(old_fs);
387 
388 	if (ret)
389 		return ret;
390 
391 	if (put_compat_rusage(&r, ru))
392 		return -EFAULT;
393 
394 	return 0;
395 }
396 
397 asmlinkage long
398 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
399 	struct compat_rusage __user *ru)
400 {
401 	if (!ru) {
402 		return sys_wait4(pid, stat_addr, options, NULL);
403 	} else {
404 		struct rusage r;
405 		int ret;
406 		unsigned int status;
407 		mm_segment_t old_fs = get_fs();
408 
409 		set_fs (KERNEL_DS);
410 		ret = sys_wait4(pid,
411 				(stat_addr ?
412 				 (unsigned int __user *) &status : NULL),
413 				options, (struct rusage __user *) &r);
414 		set_fs (old_fs);
415 
416 		if (ret > 0) {
417 			if (put_compat_rusage(&r, ru))
418 				return -EFAULT;
419 			if (stat_addr && put_user(status, stat_addr))
420 				return -EFAULT;
421 		}
422 		return ret;
423 	}
424 }
425 
426 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
427 		struct compat_siginfo __user *uinfo, int options,
428 		struct compat_rusage __user *uru)
429 {
430 	siginfo_t info;
431 	struct rusage ru;
432 	long ret;
433 	mm_segment_t old_fs = get_fs();
434 
435 	memset(&info, 0, sizeof(info));
436 
437 	set_fs(KERNEL_DS);
438 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
439 			 uru ? (struct rusage __user *)&ru : NULL);
440 	set_fs(old_fs);
441 
442 	if ((ret < 0) || (info.si_signo == 0))
443 		return ret;
444 
445 	if (uru) {
446 		ret = put_compat_rusage(&ru, uru);
447 		if (ret)
448 			return ret;
449 	}
450 
451 	BUG_ON(info.si_code & __SI_MASK);
452 	info.si_code |= __SI_CHLD;
453 	return copy_siginfo_to_user32(uinfo, &info);
454 }
455 
456 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
457 				    unsigned len, cpumask_t *new_mask)
458 {
459 	unsigned long *k;
460 
461 	if (len < sizeof(cpumask_t))
462 		memset(new_mask, 0, sizeof(cpumask_t));
463 	else if (len > sizeof(cpumask_t))
464 		len = sizeof(cpumask_t);
465 
466 	k = cpus_addr(*new_mask);
467 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
468 }
469 
470 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
471 					     unsigned int len,
472 					     compat_ulong_t __user *user_mask_ptr)
473 {
474 	cpumask_t new_mask;
475 	int retval;
476 
477 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, &new_mask);
478 	if (retval)
479 		return retval;
480 
481 	return sched_setaffinity(pid, &new_mask);
482 }
483 
484 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
485 					     compat_ulong_t __user *user_mask_ptr)
486 {
487 	int ret;
488 	cpumask_t mask;
489 	unsigned long *k;
490 	unsigned int min_length = sizeof(cpumask_t);
491 
492 	if (NR_CPUS <= BITS_PER_COMPAT_LONG)
493 		min_length = sizeof(compat_ulong_t);
494 
495 	if (len < min_length)
496 		return -EINVAL;
497 
498 	ret = sched_getaffinity(pid, &mask);
499 	if (ret < 0)
500 		return ret;
501 
502 	k = cpus_addr(mask);
503 	ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
504 	if (ret)
505 		return ret;
506 
507 	return min_length;
508 }
509 
510 int get_compat_itimerspec(struct itimerspec *dst,
511 			  const struct compat_itimerspec __user *src)
512 {
513 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
514 	    get_compat_timespec(&dst->it_value, &src->it_value))
515 		return -EFAULT;
516 	return 0;
517 }
518 
519 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
520 			  const struct itimerspec *src)
521 {
522 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
523 	    put_compat_timespec(&src->it_value, &dst->it_value))
524 		return -EFAULT;
525 	return 0;
526 }
527 
528 long compat_sys_timer_create(clockid_t which_clock,
529 			struct compat_sigevent __user *timer_event_spec,
530 			timer_t __user *created_timer_id)
531 {
532 	struct sigevent __user *event = NULL;
533 
534 	if (timer_event_spec) {
535 		struct sigevent kevent;
536 
537 		event = compat_alloc_user_space(sizeof(*event));
538 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
539 		    copy_to_user(event, &kevent, sizeof(*event)))
540 			return -EFAULT;
541 	}
542 
543 	return sys_timer_create(which_clock, event, created_timer_id);
544 }
545 
546 long compat_sys_timer_settime(timer_t timer_id, int flags,
547 			  struct compat_itimerspec __user *new,
548 			  struct compat_itimerspec __user *old)
549 {
550 	long err;
551 	mm_segment_t oldfs;
552 	struct itimerspec newts, oldts;
553 
554 	if (!new)
555 		return -EINVAL;
556 	if (get_compat_itimerspec(&newts, new))
557 		return -EFAULT;
558 	oldfs = get_fs();
559 	set_fs(KERNEL_DS);
560 	err = sys_timer_settime(timer_id, flags,
561 				(struct itimerspec __user *) &newts,
562 				(struct itimerspec __user *) &oldts);
563 	set_fs(oldfs);
564 	if (!err && old && put_compat_itimerspec(old, &oldts))
565 		return -EFAULT;
566 	return err;
567 }
568 
569 long compat_sys_timer_gettime(timer_t timer_id,
570 		struct compat_itimerspec __user *setting)
571 {
572 	long err;
573 	mm_segment_t oldfs;
574 	struct itimerspec ts;
575 
576 	oldfs = get_fs();
577 	set_fs(KERNEL_DS);
578 	err = sys_timer_gettime(timer_id,
579 				(struct itimerspec __user *) &ts);
580 	set_fs(oldfs);
581 	if (!err && put_compat_itimerspec(setting, &ts))
582 		return -EFAULT;
583 	return err;
584 }
585 
586 long compat_sys_clock_settime(clockid_t which_clock,
587 		struct compat_timespec __user *tp)
588 {
589 	long err;
590 	mm_segment_t oldfs;
591 	struct timespec ts;
592 
593 	if (get_compat_timespec(&ts, tp))
594 		return -EFAULT;
595 	oldfs = get_fs();
596 	set_fs(KERNEL_DS);
597 	err = sys_clock_settime(which_clock,
598 				(struct timespec __user *) &ts);
599 	set_fs(oldfs);
600 	return err;
601 }
602 
603 long compat_sys_clock_gettime(clockid_t which_clock,
604 		struct compat_timespec __user *tp)
605 {
606 	long err;
607 	mm_segment_t oldfs;
608 	struct timespec ts;
609 
610 	oldfs = get_fs();
611 	set_fs(KERNEL_DS);
612 	err = sys_clock_gettime(which_clock,
613 				(struct timespec __user *) &ts);
614 	set_fs(oldfs);
615 	if (!err && put_compat_timespec(&ts, tp))
616 		return -EFAULT;
617 	return err;
618 }
619 
620 long compat_sys_clock_getres(clockid_t which_clock,
621 		struct compat_timespec __user *tp)
622 {
623 	long err;
624 	mm_segment_t oldfs;
625 	struct timespec ts;
626 
627 	oldfs = get_fs();
628 	set_fs(KERNEL_DS);
629 	err = sys_clock_getres(which_clock,
630 			       (struct timespec __user *) &ts);
631 	set_fs(oldfs);
632 	if (!err && tp && put_compat_timespec(&ts, tp))
633 		return -EFAULT;
634 	return err;
635 }
636 
637 static long compat_clock_nanosleep_restart(struct restart_block *restart)
638 {
639 	long err;
640 	mm_segment_t oldfs;
641 	struct timespec tu;
642 	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
643 
644 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
645 	oldfs = get_fs();
646 	set_fs(KERNEL_DS);
647 	err = clock_nanosleep_restart(restart);
648 	set_fs(oldfs);
649 
650 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
651 	    put_compat_timespec(&tu, rmtp))
652 		return -EFAULT;
653 
654 	if (err == -ERESTART_RESTARTBLOCK) {
655 		restart->fn = compat_clock_nanosleep_restart;
656 		restart->nanosleep.compat_rmtp = rmtp;
657 	}
658 	return err;
659 }
660 
661 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
662 			    struct compat_timespec __user *rqtp,
663 			    struct compat_timespec __user *rmtp)
664 {
665 	long err;
666 	mm_segment_t oldfs;
667 	struct timespec in, out;
668 	struct restart_block *restart;
669 
670 	if (get_compat_timespec(&in, rqtp))
671 		return -EFAULT;
672 
673 	oldfs = get_fs();
674 	set_fs(KERNEL_DS);
675 	err = sys_clock_nanosleep(which_clock, flags,
676 				  (struct timespec __user *) &in,
677 				  (struct timespec __user *) &out);
678 	set_fs(oldfs);
679 
680 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
681 	    put_compat_timespec(&out, rmtp))
682 		return -EFAULT;
683 
684 	if (err == -ERESTART_RESTARTBLOCK) {
685 		restart = &current_thread_info()->restart_block;
686 		restart->fn = compat_clock_nanosleep_restart;
687 		restart->nanosleep.compat_rmtp = rmtp;
688 	}
689 	return err;
690 }
691 
692 /*
693  * We currently only need the following fields from the sigevent
694  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
695  * sigev_notify_thread_id).  The others are handled in user mode.
696  * We also assume that copying sigev_value.sival_int is sufficient
697  * to keep all the bits of sigev_value.sival_ptr intact.
698  */
699 int get_compat_sigevent(struct sigevent *event,
700 		const struct compat_sigevent __user *u_event)
701 {
702 	memset(event, 0, sizeof(*event));
703 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
704 		__get_user(event->sigev_value.sival_int,
705 			&u_event->sigev_value.sival_int) ||
706 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
707 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
708 		__get_user(event->sigev_notify_thread_id,
709 			&u_event->sigev_notify_thread_id))
710 		? -EFAULT : 0;
711 }
712 
713 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
714 		       unsigned long bitmap_size)
715 {
716 	int i, j;
717 	unsigned long m;
718 	compat_ulong_t um;
719 	unsigned long nr_compat_longs;
720 
721 	/* align bitmap up to nearest compat_long_t boundary */
722 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
723 
724 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
725 		return -EFAULT;
726 
727 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
728 
729 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
730 		m = 0;
731 
732 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
733 			/*
734 			 * We dont want to read past the end of the userspace
735 			 * bitmap. We must however ensure the end of the
736 			 * kernel bitmap is zeroed.
737 			 */
738 			if (nr_compat_longs-- > 0) {
739 				if (__get_user(um, umask))
740 					return -EFAULT;
741 			} else {
742 				um = 0;
743 			}
744 
745 			umask++;
746 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
747 		}
748 		*mask++ = m;
749 	}
750 
751 	return 0;
752 }
753 
754 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
755 		       unsigned long bitmap_size)
756 {
757 	int i, j;
758 	unsigned long m;
759 	compat_ulong_t um;
760 	unsigned long nr_compat_longs;
761 
762 	/* align bitmap up to nearest compat_long_t boundary */
763 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
764 
765 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
766 		return -EFAULT;
767 
768 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
769 
770 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
771 		m = *mask++;
772 
773 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
774 			um = m;
775 
776 			/*
777 			 * We dont want to write past the end of the userspace
778 			 * bitmap.
779 			 */
780 			if (nr_compat_longs-- > 0) {
781 				if (__put_user(um, umask))
782 					return -EFAULT;
783 			}
784 
785 			umask++;
786 			m >>= 4*sizeof(um);
787 			m >>= 4*sizeof(um);
788 		}
789 	}
790 
791 	return 0;
792 }
793 
794 void
795 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
796 {
797 	switch (_NSIG_WORDS) {
798 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
799 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
800 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
801 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
802 	}
803 }
804 
805 asmlinkage long
806 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
807 		struct compat_siginfo __user *uinfo,
808 		struct compat_timespec __user *uts, compat_size_t sigsetsize)
809 {
810 	compat_sigset_t s32;
811 	sigset_t s;
812 	int sig;
813 	struct timespec t;
814 	siginfo_t info;
815 	long ret, timeout = 0;
816 
817 	if (sigsetsize != sizeof(sigset_t))
818 		return -EINVAL;
819 
820 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
821 		return -EFAULT;
822 	sigset_from_compat(&s, &s32);
823 	sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
824 	signotset(&s);
825 
826 	if (uts) {
827 		if (get_compat_timespec (&t, uts))
828 			return -EFAULT;
829 		if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
830 				|| t.tv_sec < 0)
831 			return -EINVAL;
832 	}
833 
834 	spin_lock_irq(&current->sighand->siglock);
835 	sig = dequeue_signal(current, &s, &info);
836 	if (!sig) {
837 		timeout = MAX_SCHEDULE_TIMEOUT;
838 		if (uts)
839 			timeout = timespec_to_jiffies(&t)
840 				+(t.tv_sec || t.tv_nsec);
841 		if (timeout) {
842 			current->real_blocked = current->blocked;
843 			sigandsets(&current->blocked, &current->blocked, &s);
844 
845 			recalc_sigpending();
846 			spin_unlock_irq(&current->sighand->siglock);
847 
848 			timeout = schedule_timeout_interruptible(timeout);
849 
850 			spin_lock_irq(&current->sighand->siglock);
851 			sig = dequeue_signal(current, &s, &info);
852 			current->blocked = current->real_blocked;
853 			siginitset(&current->real_blocked, 0);
854 			recalc_sigpending();
855 		}
856 	}
857 	spin_unlock_irq(&current->sighand->siglock);
858 
859 	if (sig) {
860 		ret = sig;
861 		if (uinfo) {
862 			if (copy_siginfo_to_user32(uinfo, &info))
863 				ret = -EFAULT;
864 		}
865 	}else {
866 		ret = timeout?-EINTR:-EAGAIN;
867 	}
868 	return ret;
869 
870 }
871 
872 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
873 
874 /* compat_time_t is a 32 bit "long" and needs to get converted. */
875 
876 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
877 {
878 	compat_time_t i;
879 	struct timeval tv;
880 
881 	do_gettimeofday(&tv);
882 	i = tv.tv_sec;
883 
884 	if (tloc) {
885 		if (put_user(i,tloc))
886 			i = -EFAULT;
887 	}
888 	return i;
889 }
890 
891 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
892 {
893 	struct timespec tv;
894 	int err;
895 
896 	if (get_user(tv.tv_sec, tptr))
897 		return -EFAULT;
898 
899 	tv.tv_nsec = 0;
900 
901 	err = security_settime(&tv, NULL);
902 	if (err)
903 		return err;
904 
905 	do_settimeofday(&tv);
906 	return 0;
907 }
908 
909 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
910 
911 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
912 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
913 {
914 	sigset_t newset;
915 	compat_sigset_t newset32;
916 
917 	/* XXX: Don't preclude handling different sized sigset_t's.  */
918 	if (sigsetsize != sizeof(sigset_t))
919 		return -EINVAL;
920 
921 	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
922 		return -EFAULT;
923 	sigset_from_compat(&newset, &newset32);
924 	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
925 
926 	spin_lock_irq(&current->sighand->siglock);
927 	current->saved_sigmask = current->blocked;
928 	current->blocked = newset;
929 	recalc_sigpending();
930 	spin_unlock_irq(&current->sighand->siglock);
931 
932 	current->state = TASK_INTERRUPTIBLE;
933 	schedule();
934 	set_restore_sigmask();
935 	return -ERESTARTNOHAND;
936 }
937 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
938 
939 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
940 {
941 	struct timex txc;
942 	int ret;
943 
944 	memset(&txc, 0, sizeof(struct timex));
945 
946 	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
947 			__get_user(txc.modes, &utp->modes) ||
948 			__get_user(txc.offset, &utp->offset) ||
949 			__get_user(txc.freq, &utp->freq) ||
950 			__get_user(txc.maxerror, &utp->maxerror) ||
951 			__get_user(txc.esterror, &utp->esterror) ||
952 			__get_user(txc.status, &utp->status) ||
953 			__get_user(txc.constant, &utp->constant) ||
954 			__get_user(txc.precision, &utp->precision) ||
955 			__get_user(txc.tolerance, &utp->tolerance) ||
956 			__get_user(txc.time.tv_sec, &utp->time.tv_sec) ||
957 			__get_user(txc.time.tv_usec, &utp->time.tv_usec) ||
958 			__get_user(txc.tick, &utp->tick) ||
959 			__get_user(txc.ppsfreq, &utp->ppsfreq) ||
960 			__get_user(txc.jitter, &utp->jitter) ||
961 			__get_user(txc.shift, &utp->shift) ||
962 			__get_user(txc.stabil, &utp->stabil) ||
963 			__get_user(txc.jitcnt, &utp->jitcnt) ||
964 			__get_user(txc.calcnt, &utp->calcnt) ||
965 			__get_user(txc.errcnt, &utp->errcnt) ||
966 			__get_user(txc.stbcnt, &utp->stbcnt))
967 		return -EFAULT;
968 
969 	ret = do_adjtimex(&txc);
970 
971 	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
972 			__put_user(txc.modes, &utp->modes) ||
973 			__put_user(txc.offset, &utp->offset) ||
974 			__put_user(txc.freq, &utp->freq) ||
975 			__put_user(txc.maxerror, &utp->maxerror) ||
976 			__put_user(txc.esterror, &utp->esterror) ||
977 			__put_user(txc.status, &utp->status) ||
978 			__put_user(txc.constant, &utp->constant) ||
979 			__put_user(txc.precision, &utp->precision) ||
980 			__put_user(txc.tolerance, &utp->tolerance) ||
981 			__put_user(txc.time.tv_sec, &utp->time.tv_sec) ||
982 			__put_user(txc.time.tv_usec, &utp->time.tv_usec) ||
983 			__put_user(txc.tick, &utp->tick) ||
984 			__put_user(txc.ppsfreq, &utp->ppsfreq) ||
985 			__put_user(txc.jitter, &utp->jitter) ||
986 			__put_user(txc.shift, &utp->shift) ||
987 			__put_user(txc.stabil, &utp->stabil) ||
988 			__put_user(txc.jitcnt, &utp->jitcnt) ||
989 			__put_user(txc.calcnt, &utp->calcnt) ||
990 			__put_user(txc.errcnt, &utp->errcnt) ||
991 			__put_user(txc.stbcnt, &utp->stbcnt) ||
992 			__put_user(txc.tai, &utp->tai))
993 		ret = -EFAULT;
994 
995 	return ret;
996 }
997 
998 #ifdef CONFIG_NUMA
999 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1000 		compat_uptr_t __user *pages32,
1001 		const int __user *nodes,
1002 		int __user *status,
1003 		int flags)
1004 {
1005 	const void __user * __user *pages;
1006 	int i;
1007 
1008 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1009 	for (i = 0; i < nr_pages; i++) {
1010 		compat_uptr_t p;
1011 
1012 		if (get_user(p, pages32 + i) ||
1013 			put_user(compat_ptr(p), pages + i))
1014 			return -EFAULT;
1015 	}
1016 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1017 }
1018 
1019 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1020 			compat_ulong_t maxnode,
1021 			const compat_ulong_t __user *old_nodes,
1022 			const compat_ulong_t __user *new_nodes)
1023 {
1024 	unsigned long __user *old = NULL;
1025 	unsigned long __user *new = NULL;
1026 	nodemask_t tmp_mask;
1027 	unsigned long nr_bits;
1028 	unsigned long size;
1029 
1030 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1031 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1032 	if (old_nodes) {
1033 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1034 			return -EFAULT;
1035 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1036 		if (new_nodes)
1037 			new = old + size / sizeof(unsigned long);
1038 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1039 			return -EFAULT;
1040 	}
1041 	if (new_nodes) {
1042 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1043 			return -EFAULT;
1044 		if (new == NULL)
1045 			new = compat_alloc_user_space(size);
1046 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1047 			return -EFAULT;
1048 	}
1049 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1050 }
1051 #endif
1052 
1053 struct compat_sysinfo {
1054 	s32 uptime;
1055 	u32 loads[3];
1056 	u32 totalram;
1057 	u32 freeram;
1058 	u32 sharedram;
1059 	u32 bufferram;
1060 	u32 totalswap;
1061 	u32 freeswap;
1062 	u16 procs;
1063 	u16 pad;
1064 	u32 totalhigh;
1065 	u32 freehigh;
1066 	u32 mem_unit;
1067 	char _f[20-2*sizeof(u32)-sizeof(int)];
1068 };
1069 
1070 asmlinkage long
1071 compat_sys_sysinfo(struct compat_sysinfo __user *info)
1072 {
1073 	struct sysinfo s;
1074 
1075 	do_sysinfo(&s);
1076 
1077 	/* Check to see if any memory value is too large for 32-bit and scale
1078 	 *  down if needed
1079 	 */
1080 	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
1081 		int bitcount = 0;
1082 
1083 		while (s.mem_unit < PAGE_SIZE) {
1084 			s.mem_unit <<= 1;
1085 			bitcount++;
1086 		}
1087 
1088 		s.totalram >>= bitcount;
1089 		s.freeram >>= bitcount;
1090 		s.sharedram >>= bitcount;
1091 		s.bufferram >>= bitcount;
1092 		s.totalswap >>= bitcount;
1093 		s.freeswap >>= bitcount;
1094 		s.totalhigh >>= bitcount;
1095 		s.freehigh >>= bitcount;
1096 	}
1097 
1098 	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
1099 	    __put_user (s.uptime, &info->uptime) ||
1100 	    __put_user (s.loads[0], &info->loads[0]) ||
1101 	    __put_user (s.loads[1], &info->loads[1]) ||
1102 	    __put_user (s.loads[2], &info->loads[2]) ||
1103 	    __put_user (s.totalram, &info->totalram) ||
1104 	    __put_user (s.freeram, &info->freeram) ||
1105 	    __put_user (s.sharedram, &info->sharedram) ||
1106 	    __put_user (s.bufferram, &info->bufferram) ||
1107 	    __put_user (s.totalswap, &info->totalswap) ||
1108 	    __put_user (s.freeswap, &info->freeswap) ||
1109 	    __put_user (s.procs, &info->procs) ||
1110 	    __put_user (s.totalhigh, &info->totalhigh) ||
1111 	    __put_user (s.freehigh, &info->freehigh) ||
1112 	    __put_user (s.mem_unit, &info->mem_unit))
1113 		return -EFAULT;
1114 
1115 	return 0;
1116 }
1117