xref: /openbmc/linux/kernel/compat.c (revision 545e4006)
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 
27 #include <asm/uaccess.h>
28 
29 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
30 {
31 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
32 			__get_user(ts->tv_sec, &cts->tv_sec) ||
33 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
34 }
35 
36 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
37 {
38 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
39 			__put_user(ts->tv_sec, &cts->tv_sec) ||
40 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
41 }
42 
43 static long compat_nanosleep_restart(struct restart_block *restart)
44 {
45 	struct compat_timespec __user *rmtp;
46 	struct timespec rmt;
47 	mm_segment_t oldfs;
48 	long ret;
49 
50 	restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
51 	oldfs = get_fs();
52 	set_fs(KERNEL_DS);
53 	ret = hrtimer_nanosleep_restart(restart);
54 	set_fs(oldfs);
55 
56 	if (ret) {
57 		rmtp = restart->nanosleep.compat_rmtp;
58 
59 		if (rmtp && put_compat_timespec(&rmt, rmtp))
60 			return -EFAULT;
61 	}
62 
63 	return ret;
64 }
65 
66 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
67 				     struct compat_timespec __user *rmtp)
68 {
69 	struct timespec tu, rmt;
70 	mm_segment_t oldfs;
71 	long ret;
72 
73 	if (get_compat_timespec(&tu, rqtp))
74 		return -EFAULT;
75 
76 	if (!timespec_valid(&tu))
77 		return -EINVAL;
78 
79 	oldfs = get_fs();
80 	set_fs(KERNEL_DS);
81 	ret = hrtimer_nanosleep(&tu,
82 				rmtp ? (struct timespec __user *)&rmt : NULL,
83 				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
84 	set_fs(oldfs);
85 
86 	if (ret) {
87 		struct restart_block *restart
88 			= &current_thread_info()->restart_block;
89 
90 		restart->fn = compat_nanosleep_restart;
91 		restart->nanosleep.compat_rmtp = rmtp;
92 
93 		if (rmtp && put_compat_timespec(&rmt, rmtp))
94 			return -EFAULT;
95 	}
96 
97 	return ret;
98 }
99 
100 static inline long get_compat_itimerval(struct itimerval *o,
101 		struct compat_itimerval __user *i)
102 {
103 	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
104 		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
105 		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
106 		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
107 		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
108 }
109 
110 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
111 		struct itimerval *i)
112 {
113 	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
114 		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
115 		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
116 		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
117 		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
118 }
119 
120 asmlinkage long compat_sys_getitimer(int which,
121 		struct compat_itimerval __user *it)
122 {
123 	struct itimerval kit;
124 	int error;
125 
126 	error = do_getitimer(which, &kit);
127 	if (!error && put_compat_itimerval(it, &kit))
128 		error = -EFAULT;
129 	return error;
130 }
131 
132 asmlinkage long compat_sys_setitimer(int which,
133 		struct compat_itimerval __user *in,
134 		struct compat_itimerval __user *out)
135 {
136 	struct itimerval kin, kout;
137 	int error;
138 
139 	if (in) {
140 		if (get_compat_itimerval(&kin, in))
141 			return -EFAULT;
142 	} else
143 		memset(&kin, 0, sizeof(kin));
144 
145 	error = do_setitimer(which, &kin, out ? &kout : NULL);
146 	if (error || !out)
147 		return error;
148 	if (put_compat_itimerval(out, &kout))
149 		return -EFAULT;
150 	return 0;
151 }
152 
153 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
154 {
155 	/*
156 	 *	In the SMP world we might just be unlucky and have one of
157 	 *	the times increment as we use it. Since the value is an
158 	 *	atomically safe type this is just fine. Conceptually its
159 	 *	as if the syscall took an instant longer to occur.
160 	 */
161 	if (tbuf) {
162 		struct compat_tms tmp;
163 		struct task_struct *tsk = current;
164 		struct task_struct *t;
165 		cputime_t utime, stime, cutime, cstime;
166 
167 		read_lock(&tasklist_lock);
168 		utime = tsk->signal->utime;
169 		stime = tsk->signal->stime;
170 		t = tsk;
171 		do {
172 			utime = cputime_add(utime, t->utime);
173 			stime = cputime_add(stime, t->stime);
174 			t = next_thread(t);
175 		} while (t != tsk);
176 
177 		/*
178 		 * While we have tasklist_lock read-locked, no dying thread
179 		 * can be updating current->signal->[us]time.  Instead,
180 		 * we got their counts included in the live thread loop.
181 		 * However, another thread can come in right now and
182 		 * do a wait call that updates current->signal->c[us]time.
183 		 * To make sure we always see that pair updated atomically,
184 		 * we take the siglock around fetching them.
185 		 */
186 		spin_lock_irq(&tsk->sighand->siglock);
187 		cutime = tsk->signal->cutime;
188 		cstime = tsk->signal->cstime;
189 		spin_unlock_irq(&tsk->sighand->siglock);
190 		read_unlock(&tasklist_lock);
191 
192 		tmp.tms_utime = compat_jiffies_to_clock_t(cputime_to_jiffies(utime));
193 		tmp.tms_stime = compat_jiffies_to_clock_t(cputime_to_jiffies(stime));
194 		tmp.tms_cutime = compat_jiffies_to_clock_t(cputime_to_jiffies(cutime));
195 		tmp.tms_cstime = compat_jiffies_to_clock_t(cputime_to_jiffies(cstime));
196 		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
197 			return -EFAULT;
198 	}
199 	return compat_jiffies_to_clock_t(jiffies);
200 }
201 
202 /*
203  * Assumption: old_sigset_t and compat_old_sigset_t are both
204  * types that can be passed to put_user()/get_user().
205  */
206 
207 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
208 {
209 	old_sigset_t s;
210 	long ret;
211 	mm_segment_t old_fs = get_fs();
212 
213 	set_fs(KERNEL_DS);
214 	ret = sys_sigpending((old_sigset_t __user *) &s);
215 	set_fs(old_fs);
216 	if (ret == 0)
217 		ret = put_user(s, set);
218 	return ret;
219 }
220 
221 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
222 		compat_old_sigset_t __user *oset)
223 {
224 	old_sigset_t s;
225 	long ret;
226 	mm_segment_t old_fs;
227 
228 	if (set && get_user(s, set))
229 		return -EFAULT;
230 	old_fs = get_fs();
231 	set_fs(KERNEL_DS);
232 	ret = sys_sigprocmask(how,
233 			      set ? (old_sigset_t __user *) &s : NULL,
234 			      oset ? (old_sigset_t __user *) &s : NULL);
235 	set_fs(old_fs);
236 	if (ret == 0)
237 		if (oset)
238 			ret = put_user(s, oset);
239 	return ret;
240 }
241 
242 asmlinkage long compat_sys_setrlimit(unsigned int resource,
243 		struct compat_rlimit __user *rlim)
244 {
245 	struct rlimit r;
246 	int ret;
247 	mm_segment_t old_fs = get_fs ();
248 
249 	if (resource >= RLIM_NLIMITS)
250 		return -EINVAL;
251 
252 	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
253 	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
254 	    __get_user(r.rlim_max, &rlim->rlim_max))
255 		return -EFAULT;
256 
257 	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
258 		r.rlim_cur = RLIM_INFINITY;
259 	if (r.rlim_max == COMPAT_RLIM_INFINITY)
260 		r.rlim_max = RLIM_INFINITY;
261 	set_fs(KERNEL_DS);
262 	ret = sys_setrlimit(resource, (struct rlimit __user *) &r);
263 	set_fs(old_fs);
264 	return ret;
265 }
266 
267 #ifdef COMPAT_RLIM_OLD_INFINITY
268 
269 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
270 		struct compat_rlimit __user *rlim)
271 {
272 	struct rlimit r;
273 	int ret;
274 	mm_segment_t old_fs = get_fs();
275 
276 	set_fs(KERNEL_DS);
277 	ret = sys_old_getrlimit(resource, &r);
278 	set_fs(old_fs);
279 
280 	if (!ret) {
281 		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
282 			r.rlim_cur = COMPAT_RLIM_INFINITY;
283 		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
284 			r.rlim_max = COMPAT_RLIM_INFINITY;
285 
286 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
287 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
288 		    __put_user(r.rlim_max, &rlim->rlim_max))
289 			return -EFAULT;
290 	}
291 	return ret;
292 }
293 
294 #endif
295 
296 asmlinkage long compat_sys_getrlimit (unsigned int resource,
297 		struct compat_rlimit __user *rlim)
298 {
299 	struct rlimit r;
300 	int ret;
301 	mm_segment_t old_fs = get_fs();
302 
303 	set_fs(KERNEL_DS);
304 	ret = sys_getrlimit(resource, (struct rlimit __user *) &r);
305 	set_fs(old_fs);
306 	if (!ret) {
307 		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
308 			r.rlim_cur = COMPAT_RLIM_INFINITY;
309 		if (r.rlim_max > COMPAT_RLIM_INFINITY)
310 			r.rlim_max = COMPAT_RLIM_INFINITY;
311 
312 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
313 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
314 		    __put_user(r.rlim_max, &rlim->rlim_max))
315 			return -EFAULT;
316 	}
317 	return ret;
318 }
319 
320 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
321 {
322 	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
323 	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
324 	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
325 	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
326 	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
327 	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
328 	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
329 	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
330 	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
331 	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
332 	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
333 	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
334 	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
335 	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
336 	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
337 	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
338 	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
339 	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
340 	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
341 		return -EFAULT;
342 	return 0;
343 }
344 
345 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
346 {
347 	struct rusage r;
348 	int ret;
349 	mm_segment_t old_fs = get_fs();
350 
351 	set_fs(KERNEL_DS);
352 	ret = sys_getrusage(who, (struct rusage __user *) &r);
353 	set_fs(old_fs);
354 
355 	if (ret)
356 		return ret;
357 
358 	if (put_compat_rusage(&r, ru))
359 		return -EFAULT;
360 
361 	return 0;
362 }
363 
364 asmlinkage long
365 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
366 	struct compat_rusage __user *ru)
367 {
368 	if (!ru) {
369 		return sys_wait4(pid, stat_addr, options, NULL);
370 	} else {
371 		struct rusage r;
372 		int ret;
373 		unsigned int status;
374 		mm_segment_t old_fs = get_fs();
375 
376 		set_fs (KERNEL_DS);
377 		ret = sys_wait4(pid,
378 				(stat_addr ?
379 				 (unsigned int __user *) &status : NULL),
380 				options, (struct rusage __user *) &r);
381 		set_fs (old_fs);
382 
383 		if (ret > 0) {
384 			if (put_compat_rusage(&r, ru))
385 				return -EFAULT;
386 			if (stat_addr && put_user(status, stat_addr))
387 				return -EFAULT;
388 		}
389 		return ret;
390 	}
391 }
392 
393 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
394 		struct compat_siginfo __user *uinfo, int options,
395 		struct compat_rusage __user *uru)
396 {
397 	siginfo_t info;
398 	struct rusage ru;
399 	long ret;
400 	mm_segment_t old_fs = get_fs();
401 
402 	memset(&info, 0, sizeof(info));
403 
404 	set_fs(KERNEL_DS);
405 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
406 			 uru ? (struct rusage __user *)&ru : NULL);
407 	set_fs(old_fs);
408 
409 	if ((ret < 0) || (info.si_signo == 0))
410 		return ret;
411 
412 	if (uru) {
413 		ret = put_compat_rusage(&ru, uru);
414 		if (ret)
415 			return ret;
416 	}
417 
418 	BUG_ON(info.si_code & __SI_MASK);
419 	info.si_code |= __SI_CHLD;
420 	return copy_siginfo_to_user32(uinfo, &info);
421 }
422 
423 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
424 				    unsigned len, cpumask_t *new_mask)
425 {
426 	unsigned long *k;
427 
428 	if (len < sizeof(cpumask_t))
429 		memset(new_mask, 0, sizeof(cpumask_t));
430 	else if (len > sizeof(cpumask_t))
431 		len = sizeof(cpumask_t);
432 
433 	k = cpus_addr(*new_mask);
434 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
435 }
436 
437 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
438 					     unsigned int len,
439 					     compat_ulong_t __user *user_mask_ptr)
440 {
441 	cpumask_t new_mask;
442 	int retval;
443 
444 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, &new_mask);
445 	if (retval)
446 		return retval;
447 
448 	return sched_setaffinity(pid, &new_mask);
449 }
450 
451 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
452 					     compat_ulong_t __user *user_mask_ptr)
453 {
454 	int ret;
455 	cpumask_t mask;
456 	unsigned long *k;
457 	unsigned int min_length = sizeof(cpumask_t);
458 
459 	if (NR_CPUS <= BITS_PER_COMPAT_LONG)
460 		min_length = sizeof(compat_ulong_t);
461 
462 	if (len < min_length)
463 		return -EINVAL;
464 
465 	ret = sched_getaffinity(pid, &mask);
466 	if (ret < 0)
467 		return ret;
468 
469 	k = cpus_addr(mask);
470 	ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
471 	if (ret)
472 		return ret;
473 
474 	return min_length;
475 }
476 
477 int get_compat_itimerspec(struct itimerspec *dst,
478 			  const struct compat_itimerspec __user *src)
479 {
480 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
481 	    get_compat_timespec(&dst->it_value, &src->it_value))
482 		return -EFAULT;
483 	return 0;
484 }
485 
486 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
487 			  const struct itimerspec *src)
488 {
489 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
490 	    put_compat_timespec(&src->it_value, &dst->it_value))
491 		return -EFAULT;
492 	return 0;
493 }
494 
495 long compat_sys_timer_create(clockid_t which_clock,
496 			struct compat_sigevent __user *timer_event_spec,
497 			timer_t __user *created_timer_id)
498 {
499 	struct sigevent __user *event = NULL;
500 
501 	if (timer_event_spec) {
502 		struct sigevent kevent;
503 
504 		event = compat_alloc_user_space(sizeof(*event));
505 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
506 		    copy_to_user(event, &kevent, sizeof(*event)))
507 			return -EFAULT;
508 	}
509 
510 	return sys_timer_create(which_clock, event, created_timer_id);
511 }
512 
513 long compat_sys_timer_settime(timer_t timer_id, int flags,
514 			  struct compat_itimerspec __user *new,
515 			  struct compat_itimerspec __user *old)
516 {
517 	long err;
518 	mm_segment_t oldfs;
519 	struct itimerspec newts, oldts;
520 
521 	if (!new)
522 		return -EINVAL;
523 	if (get_compat_itimerspec(&newts, new))
524 		return -EFAULT;
525 	oldfs = get_fs();
526 	set_fs(KERNEL_DS);
527 	err = sys_timer_settime(timer_id, flags,
528 				(struct itimerspec __user *) &newts,
529 				(struct itimerspec __user *) &oldts);
530 	set_fs(oldfs);
531 	if (!err && old && put_compat_itimerspec(old, &oldts))
532 		return -EFAULT;
533 	return err;
534 }
535 
536 long compat_sys_timer_gettime(timer_t timer_id,
537 		struct compat_itimerspec __user *setting)
538 {
539 	long err;
540 	mm_segment_t oldfs;
541 	struct itimerspec ts;
542 
543 	oldfs = get_fs();
544 	set_fs(KERNEL_DS);
545 	err = sys_timer_gettime(timer_id,
546 				(struct itimerspec __user *) &ts);
547 	set_fs(oldfs);
548 	if (!err && put_compat_itimerspec(setting, &ts))
549 		return -EFAULT;
550 	return err;
551 }
552 
553 long compat_sys_clock_settime(clockid_t which_clock,
554 		struct compat_timespec __user *tp)
555 {
556 	long err;
557 	mm_segment_t oldfs;
558 	struct timespec ts;
559 
560 	if (get_compat_timespec(&ts, tp))
561 		return -EFAULT;
562 	oldfs = get_fs();
563 	set_fs(KERNEL_DS);
564 	err = sys_clock_settime(which_clock,
565 				(struct timespec __user *) &ts);
566 	set_fs(oldfs);
567 	return err;
568 }
569 
570 long compat_sys_clock_gettime(clockid_t which_clock,
571 		struct compat_timespec __user *tp)
572 {
573 	long err;
574 	mm_segment_t oldfs;
575 	struct timespec ts;
576 
577 	oldfs = get_fs();
578 	set_fs(KERNEL_DS);
579 	err = sys_clock_gettime(which_clock,
580 				(struct timespec __user *) &ts);
581 	set_fs(oldfs);
582 	if (!err && put_compat_timespec(&ts, tp))
583 		return -EFAULT;
584 	return err;
585 }
586 
587 long compat_sys_clock_getres(clockid_t which_clock,
588 		struct compat_timespec __user *tp)
589 {
590 	long err;
591 	mm_segment_t oldfs;
592 	struct timespec ts;
593 
594 	oldfs = get_fs();
595 	set_fs(KERNEL_DS);
596 	err = sys_clock_getres(which_clock,
597 			       (struct timespec __user *) &ts);
598 	set_fs(oldfs);
599 	if (!err && tp && put_compat_timespec(&ts, tp))
600 		return -EFAULT;
601 	return err;
602 }
603 
604 static long compat_clock_nanosleep_restart(struct restart_block *restart)
605 {
606 	long err;
607 	mm_segment_t oldfs;
608 	struct timespec tu;
609 	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
610 
611 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
612 	oldfs = get_fs();
613 	set_fs(KERNEL_DS);
614 	err = clock_nanosleep_restart(restart);
615 	set_fs(oldfs);
616 
617 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
618 	    put_compat_timespec(&tu, rmtp))
619 		return -EFAULT;
620 
621 	if (err == -ERESTART_RESTARTBLOCK) {
622 		restart->fn = compat_clock_nanosleep_restart;
623 		restart->nanosleep.compat_rmtp = rmtp;
624 	}
625 	return err;
626 }
627 
628 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
629 			    struct compat_timespec __user *rqtp,
630 			    struct compat_timespec __user *rmtp)
631 {
632 	long err;
633 	mm_segment_t oldfs;
634 	struct timespec in, out;
635 	struct restart_block *restart;
636 
637 	if (get_compat_timespec(&in, rqtp))
638 		return -EFAULT;
639 
640 	oldfs = get_fs();
641 	set_fs(KERNEL_DS);
642 	err = sys_clock_nanosleep(which_clock, flags,
643 				  (struct timespec __user *) &in,
644 				  (struct timespec __user *) &out);
645 	set_fs(oldfs);
646 
647 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
648 	    put_compat_timespec(&out, rmtp))
649 		return -EFAULT;
650 
651 	if (err == -ERESTART_RESTARTBLOCK) {
652 		restart = &current_thread_info()->restart_block;
653 		restart->fn = compat_clock_nanosleep_restart;
654 		restart->nanosleep.compat_rmtp = rmtp;
655 	}
656 	return err;
657 }
658 
659 /*
660  * We currently only need the following fields from the sigevent
661  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
662  * sigev_notify_thread_id).  The others are handled in user mode.
663  * We also assume that copying sigev_value.sival_int is sufficient
664  * to keep all the bits of sigev_value.sival_ptr intact.
665  */
666 int get_compat_sigevent(struct sigevent *event,
667 		const struct compat_sigevent __user *u_event)
668 {
669 	memset(event, 0, sizeof(*event));
670 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
671 		__get_user(event->sigev_value.sival_int,
672 			&u_event->sigev_value.sival_int) ||
673 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
674 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
675 		__get_user(event->sigev_notify_thread_id,
676 			&u_event->sigev_notify_thread_id))
677 		? -EFAULT : 0;
678 }
679 
680 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
681 		       unsigned long bitmap_size)
682 {
683 	int i, j;
684 	unsigned long m;
685 	compat_ulong_t um;
686 	unsigned long nr_compat_longs;
687 
688 	/* align bitmap up to nearest compat_long_t boundary */
689 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
690 
691 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
692 		return -EFAULT;
693 
694 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
695 
696 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
697 		m = 0;
698 
699 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
700 			/*
701 			 * We dont want to read past the end of the userspace
702 			 * bitmap. We must however ensure the end of the
703 			 * kernel bitmap is zeroed.
704 			 */
705 			if (nr_compat_longs-- > 0) {
706 				if (__get_user(um, umask))
707 					return -EFAULT;
708 			} else {
709 				um = 0;
710 			}
711 
712 			umask++;
713 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
714 		}
715 		*mask++ = m;
716 	}
717 
718 	return 0;
719 }
720 
721 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
722 		       unsigned long bitmap_size)
723 {
724 	int i, j;
725 	unsigned long m;
726 	compat_ulong_t um;
727 	unsigned long nr_compat_longs;
728 
729 	/* align bitmap up to nearest compat_long_t boundary */
730 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
731 
732 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
733 		return -EFAULT;
734 
735 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
736 
737 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
738 		m = *mask++;
739 
740 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
741 			um = m;
742 
743 			/*
744 			 * We dont want to write past the end of the userspace
745 			 * bitmap.
746 			 */
747 			if (nr_compat_longs-- > 0) {
748 				if (__put_user(um, umask))
749 					return -EFAULT;
750 			}
751 
752 			umask++;
753 			m >>= 4*sizeof(um);
754 			m >>= 4*sizeof(um);
755 		}
756 	}
757 
758 	return 0;
759 }
760 
761 void
762 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
763 {
764 	switch (_NSIG_WORDS) {
765 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
766 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
767 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
768 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
769 	}
770 }
771 
772 asmlinkage long
773 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
774 		struct compat_siginfo __user *uinfo,
775 		struct compat_timespec __user *uts, compat_size_t sigsetsize)
776 {
777 	compat_sigset_t s32;
778 	sigset_t s;
779 	int sig;
780 	struct timespec t;
781 	siginfo_t info;
782 	long ret, timeout = 0;
783 
784 	if (sigsetsize != sizeof(sigset_t))
785 		return -EINVAL;
786 
787 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
788 		return -EFAULT;
789 	sigset_from_compat(&s, &s32);
790 	sigdelsetmask(&s,sigmask(SIGKILL)|sigmask(SIGSTOP));
791 	signotset(&s);
792 
793 	if (uts) {
794 		if (get_compat_timespec (&t, uts))
795 			return -EFAULT;
796 		if (t.tv_nsec >= 1000000000L || t.tv_nsec < 0
797 				|| t.tv_sec < 0)
798 			return -EINVAL;
799 	}
800 
801 	spin_lock_irq(&current->sighand->siglock);
802 	sig = dequeue_signal(current, &s, &info);
803 	if (!sig) {
804 		timeout = MAX_SCHEDULE_TIMEOUT;
805 		if (uts)
806 			timeout = timespec_to_jiffies(&t)
807 				+(t.tv_sec || t.tv_nsec);
808 		if (timeout) {
809 			current->real_blocked = current->blocked;
810 			sigandsets(&current->blocked, &current->blocked, &s);
811 
812 			recalc_sigpending();
813 			spin_unlock_irq(&current->sighand->siglock);
814 
815 			timeout = schedule_timeout_interruptible(timeout);
816 
817 			spin_lock_irq(&current->sighand->siglock);
818 			sig = dequeue_signal(current, &s, &info);
819 			current->blocked = current->real_blocked;
820 			siginitset(&current->real_blocked, 0);
821 			recalc_sigpending();
822 		}
823 	}
824 	spin_unlock_irq(&current->sighand->siglock);
825 
826 	if (sig) {
827 		ret = sig;
828 		if (uinfo) {
829 			if (copy_siginfo_to_user32(uinfo, &info))
830 				ret = -EFAULT;
831 		}
832 	}else {
833 		ret = timeout?-EINTR:-EAGAIN;
834 	}
835 	return ret;
836 
837 }
838 
839 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
840 
841 /* compat_time_t is a 32 bit "long" and needs to get converted. */
842 
843 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
844 {
845 	compat_time_t i;
846 	struct timeval tv;
847 
848 	do_gettimeofday(&tv);
849 	i = tv.tv_sec;
850 
851 	if (tloc) {
852 		if (put_user(i,tloc))
853 			i = -EFAULT;
854 	}
855 	return i;
856 }
857 
858 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
859 {
860 	struct timespec tv;
861 	int err;
862 
863 	if (get_user(tv.tv_sec, tptr))
864 		return -EFAULT;
865 
866 	tv.tv_nsec = 0;
867 
868 	err = security_settime(&tv, NULL);
869 	if (err)
870 		return err;
871 
872 	do_settimeofday(&tv);
873 	return 0;
874 }
875 
876 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
877 
878 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
879 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
880 {
881 	sigset_t newset;
882 	compat_sigset_t newset32;
883 
884 	/* XXX: Don't preclude handling different sized sigset_t's.  */
885 	if (sigsetsize != sizeof(sigset_t))
886 		return -EINVAL;
887 
888 	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
889 		return -EFAULT;
890 	sigset_from_compat(&newset, &newset32);
891 	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
892 
893 	spin_lock_irq(&current->sighand->siglock);
894 	current->saved_sigmask = current->blocked;
895 	current->blocked = newset;
896 	recalc_sigpending();
897 	spin_unlock_irq(&current->sighand->siglock);
898 
899 	current->state = TASK_INTERRUPTIBLE;
900 	schedule();
901 	set_restore_sigmask();
902 	return -ERESTARTNOHAND;
903 }
904 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
905 
906 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
907 {
908 	struct timex txc;
909 	int ret;
910 
911 	memset(&txc, 0, sizeof(struct timex));
912 
913 	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
914 			__get_user(txc.modes, &utp->modes) ||
915 			__get_user(txc.offset, &utp->offset) ||
916 			__get_user(txc.freq, &utp->freq) ||
917 			__get_user(txc.maxerror, &utp->maxerror) ||
918 			__get_user(txc.esterror, &utp->esterror) ||
919 			__get_user(txc.status, &utp->status) ||
920 			__get_user(txc.constant, &utp->constant) ||
921 			__get_user(txc.precision, &utp->precision) ||
922 			__get_user(txc.tolerance, &utp->tolerance) ||
923 			__get_user(txc.time.tv_sec, &utp->time.tv_sec) ||
924 			__get_user(txc.time.tv_usec, &utp->time.tv_usec) ||
925 			__get_user(txc.tick, &utp->tick) ||
926 			__get_user(txc.ppsfreq, &utp->ppsfreq) ||
927 			__get_user(txc.jitter, &utp->jitter) ||
928 			__get_user(txc.shift, &utp->shift) ||
929 			__get_user(txc.stabil, &utp->stabil) ||
930 			__get_user(txc.jitcnt, &utp->jitcnt) ||
931 			__get_user(txc.calcnt, &utp->calcnt) ||
932 			__get_user(txc.errcnt, &utp->errcnt) ||
933 			__get_user(txc.stbcnt, &utp->stbcnt))
934 		return -EFAULT;
935 
936 	ret = do_adjtimex(&txc);
937 
938 	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
939 			__put_user(txc.modes, &utp->modes) ||
940 			__put_user(txc.offset, &utp->offset) ||
941 			__put_user(txc.freq, &utp->freq) ||
942 			__put_user(txc.maxerror, &utp->maxerror) ||
943 			__put_user(txc.esterror, &utp->esterror) ||
944 			__put_user(txc.status, &utp->status) ||
945 			__put_user(txc.constant, &utp->constant) ||
946 			__put_user(txc.precision, &utp->precision) ||
947 			__put_user(txc.tolerance, &utp->tolerance) ||
948 			__put_user(txc.time.tv_sec, &utp->time.tv_sec) ||
949 			__put_user(txc.time.tv_usec, &utp->time.tv_usec) ||
950 			__put_user(txc.tick, &utp->tick) ||
951 			__put_user(txc.ppsfreq, &utp->ppsfreq) ||
952 			__put_user(txc.jitter, &utp->jitter) ||
953 			__put_user(txc.shift, &utp->shift) ||
954 			__put_user(txc.stabil, &utp->stabil) ||
955 			__put_user(txc.jitcnt, &utp->jitcnt) ||
956 			__put_user(txc.calcnt, &utp->calcnt) ||
957 			__put_user(txc.errcnt, &utp->errcnt) ||
958 			__put_user(txc.stbcnt, &utp->stbcnt) ||
959 			__put_user(txc.tai, &utp->tai))
960 		ret = -EFAULT;
961 
962 	return ret;
963 }
964 
965 #ifdef CONFIG_NUMA
966 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
967 		compat_uptr_t __user *pages32,
968 		const int __user *nodes,
969 		int __user *status,
970 		int flags)
971 {
972 	const void __user * __user *pages;
973 	int i;
974 
975 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
976 	for (i = 0; i < nr_pages; i++) {
977 		compat_uptr_t p;
978 
979 		if (get_user(p, pages32 + i) ||
980 			put_user(compat_ptr(p), pages + i))
981 			return -EFAULT;
982 	}
983 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
984 }
985 
986 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
987 			compat_ulong_t maxnode,
988 			const compat_ulong_t __user *old_nodes,
989 			const compat_ulong_t __user *new_nodes)
990 {
991 	unsigned long __user *old = NULL;
992 	unsigned long __user *new = NULL;
993 	nodemask_t tmp_mask;
994 	unsigned long nr_bits;
995 	unsigned long size;
996 
997 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
998 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
999 	if (old_nodes) {
1000 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1001 			return -EFAULT;
1002 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1003 		if (new_nodes)
1004 			new = old + size / sizeof(unsigned long);
1005 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1006 			return -EFAULT;
1007 	}
1008 	if (new_nodes) {
1009 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1010 			return -EFAULT;
1011 		if (new == NULL)
1012 			new = compat_alloc_user_space(size);
1013 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1014 			return -EFAULT;
1015 	}
1016 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1017 }
1018 #endif
1019 
1020 struct compat_sysinfo {
1021 	s32 uptime;
1022 	u32 loads[3];
1023 	u32 totalram;
1024 	u32 freeram;
1025 	u32 sharedram;
1026 	u32 bufferram;
1027 	u32 totalswap;
1028 	u32 freeswap;
1029 	u16 procs;
1030 	u16 pad;
1031 	u32 totalhigh;
1032 	u32 freehigh;
1033 	u32 mem_unit;
1034 	char _f[20-2*sizeof(u32)-sizeof(int)];
1035 };
1036 
1037 asmlinkage long
1038 compat_sys_sysinfo(struct compat_sysinfo __user *info)
1039 {
1040 	struct sysinfo s;
1041 
1042 	do_sysinfo(&s);
1043 
1044 	/* Check to see if any memory value is too large for 32-bit and scale
1045 	 *  down if needed
1046 	 */
1047 	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
1048 		int bitcount = 0;
1049 
1050 		while (s.mem_unit < PAGE_SIZE) {
1051 			s.mem_unit <<= 1;
1052 			bitcount++;
1053 		}
1054 
1055 		s.totalram >>= bitcount;
1056 		s.freeram >>= bitcount;
1057 		s.sharedram >>= bitcount;
1058 		s.bufferram >>= bitcount;
1059 		s.totalswap >>= bitcount;
1060 		s.freeswap >>= bitcount;
1061 		s.totalhigh >>= bitcount;
1062 		s.freehigh >>= bitcount;
1063 	}
1064 
1065 	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
1066 	    __put_user (s.uptime, &info->uptime) ||
1067 	    __put_user (s.loads[0], &info->loads[0]) ||
1068 	    __put_user (s.loads[1], &info->loads[1]) ||
1069 	    __put_user (s.loads[2], &info->loads[2]) ||
1070 	    __put_user (s.totalram, &info->totalram) ||
1071 	    __put_user (s.freeram, &info->freeram) ||
1072 	    __put_user (s.sharedram, &info->sharedram) ||
1073 	    __put_user (s.bufferram, &info->bufferram) ||
1074 	    __put_user (s.totalswap, &info->totalswap) ||
1075 	    __put_user (s.freeswap, &info->freeswap) ||
1076 	    __put_user (s.procs, &info->procs) ||
1077 	    __put_user (s.totalhigh, &info->totalhigh) ||
1078 	    __put_user (s.freehigh, &info->freehigh) ||
1079 	    __put_user (s.mem_unit, &info->mem_unit))
1080 		return -EFAULT;
1081 
1082 	return 0;
1083 }
1084