xref: /openbmc/linux/kernel/compat.c (revision 9c1f8594)
1 /*
2  *  linux/kernel/compat.c
3  *
4  *  Kernel compatibililty routines for e.g. 32 bit syscall support
5  *  on 64 bit kernels.
6  *
7  *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2 as
11  *  published by the Free Software Foundation.
12  */
13 
14 #include <linux/linkage.h>
15 #include <linux/compat.h>
16 #include <linux/errno.h>
17 #include <linux/time.h>
18 #include <linux/signal.h>
19 #include <linux/sched.h>	/* for MAX_SCHEDULE_TIMEOUT */
20 #include <linux/syscalls.h>
21 #include <linux/unistd.h>
22 #include <linux/security.h>
23 #include <linux/timex.h>
24 #include <linux/migrate.h>
25 #include <linux/posix-timers.h>
26 #include <linux/times.h>
27 #include <linux/ptrace.h>
28 #include <linux/gfp.h>
29 
30 #include <asm/uaccess.h>
31 
32 /*
33  * Note that the native side is already converted to a timespec, because
34  * that's what we want anyway.
35  */
36 static int compat_get_timeval(struct timespec *o,
37 		struct compat_timeval __user *i)
38 {
39 	long usec;
40 
41 	if (get_user(o->tv_sec, &i->tv_sec) ||
42 	    get_user(usec, &i->tv_usec))
43 		return -EFAULT;
44 	o->tv_nsec = usec * 1000;
45 	return 0;
46 }
47 
48 static int compat_put_timeval(struct compat_timeval __user *o,
49 		struct timeval *i)
50 {
51 	return (put_user(i->tv_sec, &o->tv_sec) ||
52 		put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
53 }
54 
55 static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
56 {
57 	memset(txc, 0, sizeof(struct timex));
58 
59 	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
60 			__get_user(txc->modes, &utp->modes) ||
61 			__get_user(txc->offset, &utp->offset) ||
62 			__get_user(txc->freq, &utp->freq) ||
63 			__get_user(txc->maxerror, &utp->maxerror) ||
64 			__get_user(txc->esterror, &utp->esterror) ||
65 			__get_user(txc->status, &utp->status) ||
66 			__get_user(txc->constant, &utp->constant) ||
67 			__get_user(txc->precision, &utp->precision) ||
68 			__get_user(txc->tolerance, &utp->tolerance) ||
69 			__get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
70 			__get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
71 			__get_user(txc->tick, &utp->tick) ||
72 			__get_user(txc->ppsfreq, &utp->ppsfreq) ||
73 			__get_user(txc->jitter, &utp->jitter) ||
74 			__get_user(txc->shift, &utp->shift) ||
75 			__get_user(txc->stabil, &utp->stabil) ||
76 			__get_user(txc->jitcnt, &utp->jitcnt) ||
77 			__get_user(txc->calcnt, &utp->calcnt) ||
78 			__get_user(txc->errcnt, &utp->errcnt) ||
79 			__get_user(txc->stbcnt, &utp->stbcnt))
80 		return -EFAULT;
81 
82 	return 0;
83 }
84 
85 static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
86 {
87 	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
88 			__put_user(txc->modes, &utp->modes) ||
89 			__put_user(txc->offset, &utp->offset) ||
90 			__put_user(txc->freq, &utp->freq) ||
91 			__put_user(txc->maxerror, &utp->maxerror) ||
92 			__put_user(txc->esterror, &utp->esterror) ||
93 			__put_user(txc->status, &utp->status) ||
94 			__put_user(txc->constant, &utp->constant) ||
95 			__put_user(txc->precision, &utp->precision) ||
96 			__put_user(txc->tolerance, &utp->tolerance) ||
97 			__put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
98 			__put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
99 			__put_user(txc->tick, &utp->tick) ||
100 			__put_user(txc->ppsfreq, &utp->ppsfreq) ||
101 			__put_user(txc->jitter, &utp->jitter) ||
102 			__put_user(txc->shift, &utp->shift) ||
103 			__put_user(txc->stabil, &utp->stabil) ||
104 			__put_user(txc->jitcnt, &utp->jitcnt) ||
105 			__put_user(txc->calcnt, &utp->calcnt) ||
106 			__put_user(txc->errcnt, &utp->errcnt) ||
107 			__put_user(txc->stbcnt, &utp->stbcnt) ||
108 			__put_user(txc->tai, &utp->tai))
109 		return -EFAULT;
110 	return 0;
111 }
112 
113 asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
114 		struct timezone __user *tz)
115 {
116 	if (tv) {
117 		struct timeval ktv;
118 		do_gettimeofday(&ktv);
119 		if (compat_put_timeval(tv, &ktv))
120 			return -EFAULT;
121 	}
122 	if (tz) {
123 		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
124 			return -EFAULT;
125 	}
126 
127 	return 0;
128 }
129 
130 asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
131 		struct timezone __user *tz)
132 {
133 	struct timespec kts;
134 	struct timezone ktz;
135 
136 	if (tv) {
137 		if (compat_get_timeval(&kts, tv))
138 			return -EFAULT;
139 	}
140 	if (tz) {
141 		if (copy_from_user(&ktz, tz, sizeof(ktz)))
142 			return -EFAULT;
143 	}
144 
145 	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
146 }
147 
148 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
149 {
150 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
151 			__get_user(ts->tv_sec, &cts->tv_sec) ||
152 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
153 }
154 
155 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
156 {
157 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
158 			__put_user(ts->tv_sec, &cts->tv_sec) ||
159 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
160 }
161 EXPORT_SYMBOL_GPL(put_compat_timespec);
162 
163 static long compat_nanosleep_restart(struct restart_block *restart)
164 {
165 	struct compat_timespec __user *rmtp;
166 	struct timespec rmt;
167 	mm_segment_t oldfs;
168 	long ret;
169 
170 	restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
171 	oldfs = get_fs();
172 	set_fs(KERNEL_DS);
173 	ret = hrtimer_nanosleep_restart(restart);
174 	set_fs(oldfs);
175 
176 	if (ret) {
177 		rmtp = restart->nanosleep.compat_rmtp;
178 
179 		if (rmtp && put_compat_timespec(&rmt, rmtp))
180 			return -EFAULT;
181 	}
182 
183 	return ret;
184 }
185 
186 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
187 				     struct compat_timespec __user *rmtp)
188 {
189 	struct timespec tu, rmt;
190 	mm_segment_t oldfs;
191 	long ret;
192 
193 	if (get_compat_timespec(&tu, rqtp))
194 		return -EFAULT;
195 
196 	if (!timespec_valid(&tu))
197 		return -EINVAL;
198 
199 	oldfs = get_fs();
200 	set_fs(KERNEL_DS);
201 	ret = hrtimer_nanosleep(&tu,
202 				rmtp ? (struct timespec __user *)&rmt : NULL,
203 				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
204 	set_fs(oldfs);
205 
206 	if (ret) {
207 		struct restart_block *restart
208 			= &current_thread_info()->restart_block;
209 
210 		restart->fn = compat_nanosleep_restart;
211 		restart->nanosleep.compat_rmtp = rmtp;
212 
213 		if (rmtp && put_compat_timespec(&rmt, rmtp))
214 			return -EFAULT;
215 	}
216 
217 	return ret;
218 }
219 
220 static inline long get_compat_itimerval(struct itimerval *o,
221 		struct compat_itimerval __user *i)
222 {
223 	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
224 		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
225 		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
226 		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
227 		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
228 }
229 
230 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
231 		struct itimerval *i)
232 {
233 	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
234 		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
235 		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
236 		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
237 		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
238 }
239 
240 asmlinkage long compat_sys_getitimer(int which,
241 		struct compat_itimerval __user *it)
242 {
243 	struct itimerval kit;
244 	int error;
245 
246 	error = do_getitimer(which, &kit);
247 	if (!error && put_compat_itimerval(it, &kit))
248 		error = -EFAULT;
249 	return error;
250 }
251 
252 asmlinkage long compat_sys_setitimer(int which,
253 		struct compat_itimerval __user *in,
254 		struct compat_itimerval __user *out)
255 {
256 	struct itimerval kin, kout;
257 	int error;
258 
259 	if (in) {
260 		if (get_compat_itimerval(&kin, in))
261 			return -EFAULT;
262 	} else
263 		memset(&kin, 0, sizeof(kin));
264 
265 	error = do_setitimer(which, &kin, out ? &kout : NULL);
266 	if (error || !out)
267 		return error;
268 	if (put_compat_itimerval(out, &kout))
269 		return -EFAULT;
270 	return 0;
271 }
272 
273 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
274 {
275 	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
276 }
277 
278 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
279 {
280 	if (tbuf) {
281 		struct tms tms;
282 		struct compat_tms tmp;
283 
284 		do_sys_times(&tms);
285 		/* Convert our struct tms to the compat version. */
286 		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
287 		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
288 		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
289 		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
290 		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
291 			return -EFAULT;
292 	}
293 	force_successful_syscall_return();
294 	return compat_jiffies_to_clock_t(jiffies);
295 }
296 
297 #ifdef __ARCH_WANT_SYS_SIGPENDING
298 
299 /*
300  * Assumption: old_sigset_t and compat_old_sigset_t are both
301  * types that can be passed to put_user()/get_user().
302  */
303 
304 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
305 {
306 	old_sigset_t s;
307 	long ret;
308 	mm_segment_t old_fs = get_fs();
309 
310 	set_fs(KERNEL_DS);
311 	ret = sys_sigpending((old_sigset_t __user *) &s);
312 	set_fs(old_fs);
313 	if (ret == 0)
314 		ret = put_user(s, set);
315 	return ret;
316 }
317 
318 #endif
319 
320 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
321 
322 asmlinkage long compat_sys_sigprocmask(int how, compat_old_sigset_t __user *set,
323 		compat_old_sigset_t __user *oset)
324 {
325 	old_sigset_t s;
326 	long ret;
327 	mm_segment_t old_fs;
328 
329 	if (set && get_user(s, set))
330 		return -EFAULT;
331 	old_fs = get_fs();
332 	set_fs(KERNEL_DS);
333 	ret = sys_sigprocmask(how,
334 			      set ? (old_sigset_t __user *) &s : NULL,
335 			      oset ? (old_sigset_t __user *) &s : NULL);
336 	set_fs(old_fs);
337 	if (ret == 0)
338 		if (oset)
339 			ret = put_user(s, oset);
340 	return ret;
341 }
342 
343 #endif
344 
345 asmlinkage long compat_sys_setrlimit(unsigned int resource,
346 		struct compat_rlimit __user *rlim)
347 {
348 	struct rlimit r;
349 
350 	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
351 	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
352 	    __get_user(r.rlim_max, &rlim->rlim_max))
353 		return -EFAULT;
354 
355 	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
356 		r.rlim_cur = RLIM_INFINITY;
357 	if (r.rlim_max == COMPAT_RLIM_INFINITY)
358 		r.rlim_max = RLIM_INFINITY;
359 	return do_prlimit(current, resource, &r, NULL);
360 }
361 
362 #ifdef COMPAT_RLIM_OLD_INFINITY
363 
364 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
365 		struct compat_rlimit __user *rlim)
366 {
367 	struct rlimit r;
368 	int ret;
369 	mm_segment_t old_fs = get_fs();
370 
371 	set_fs(KERNEL_DS);
372 	ret = sys_old_getrlimit(resource, &r);
373 	set_fs(old_fs);
374 
375 	if (!ret) {
376 		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
377 			r.rlim_cur = COMPAT_RLIM_INFINITY;
378 		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
379 			r.rlim_max = COMPAT_RLIM_INFINITY;
380 
381 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
382 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
383 		    __put_user(r.rlim_max, &rlim->rlim_max))
384 			return -EFAULT;
385 	}
386 	return ret;
387 }
388 
389 #endif
390 
391 asmlinkage long compat_sys_getrlimit(unsigned int resource,
392 		struct compat_rlimit __user *rlim)
393 {
394 	struct rlimit r;
395 	int ret;
396 
397 	ret = do_prlimit(current, resource, NULL, &r);
398 	if (!ret) {
399 		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
400 			r.rlim_cur = COMPAT_RLIM_INFINITY;
401 		if (r.rlim_max > COMPAT_RLIM_INFINITY)
402 			r.rlim_max = COMPAT_RLIM_INFINITY;
403 
404 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
405 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
406 		    __put_user(r.rlim_max, &rlim->rlim_max))
407 			return -EFAULT;
408 	}
409 	return ret;
410 }
411 
412 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
413 {
414 	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
415 	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
416 	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
417 	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
418 	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
419 	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
420 	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
421 	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
422 	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
423 	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
424 	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
425 	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
426 	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
427 	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
428 	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
429 	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
430 	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
431 	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
432 	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
433 		return -EFAULT;
434 	return 0;
435 }
436 
437 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
438 {
439 	struct rusage r;
440 	int ret;
441 	mm_segment_t old_fs = get_fs();
442 
443 	set_fs(KERNEL_DS);
444 	ret = sys_getrusage(who, (struct rusage __user *) &r);
445 	set_fs(old_fs);
446 
447 	if (ret)
448 		return ret;
449 
450 	if (put_compat_rusage(&r, ru))
451 		return -EFAULT;
452 
453 	return 0;
454 }
455 
456 asmlinkage long
457 compat_sys_wait4(compat_pid_t pid, compat_uint_t __user *stat_addr, int options,
458 	struct compat_rusage __user *ru)
459 {
460 	if (!ru) {
461 		return sys_wait4(pid, stat_addr, options, NULL);
462 	} else {
463 		struct rusage r;
464 		int ret;
465 		unsigned int status;
466 		mm_segment_t old_fs = get_fs();
467 
468 		set_fs (KERNEL_DS);
469 		ret = sys_wait4(pid,
470 				(stat_addr ?
471 				 (unsigned int __user *) &status : NULL),
472 				options, (struct rusage __user *) &r);
473 		set_fs (old_fs);
474 
475 		if (ret > 0) {
476 			if (put_compat_rusage(&r, ru))
477 				return -EFAULT;
478 			if (stat_addr && put_user(status, stat_addr))
479 				return -EFAULT;
480 		}
481 		return ret;
482 	}
483 }
484 
485 asmlinkage long compat_sys_waitid(int which, compat_pid_t pid,
486 		struct compat_siginfo __user *uinfo, int options,
487 		struct compat_rusage __user *uru)
488 {
489 	siginfo_t info;
490 	struct rusage ru;
491 	long ret;
492 	mm_segment_t old_fs = get_fs();
493 
494 	memset(&info, 0, sizeof(info));
495 
496 	set_fs(KERNEL_DS);
497 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
498 			 uru ? (struct rusage __user *)&ru : NULL);
499 	set_fs(old_fs);
500 
501 	if ((ret < 0) || (info.si_signo == 0))
502 		return ret;
503 
504 	if (uru) {
505 		ret = put_compat_rusage(&ru, uru);
506 		if (ret)
507 			return ret;
508 	}
509 
510 	BUG_ON(info.si_code & __SI_MASK);
511 	info.si_code |= __SI_CHLD;
512 	return copy_siginfo_to_user32(uinfo, &info);
513 }
514 
515 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
516 				    unsigned len, struct cpumask *new_mask)
517 {
518 	unsigned long *k;
519 
520 	if (len < cpumask_size())
521 		memset(new_mask, 0, cpumask_size());
522 	else if (len > cpumask_size())
523 		len = cpumask_size();
524 
525 	k = cpumask_bits(new_mask);
526 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
527 }
528 
529 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
530 					     unsigned int len,
531 					     compat_ulong_t __user *user_mask_ptr)
532 {
533 	cpumask_var_t new_mask;
534 	int retval;
535 
536 	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
537 		return -ENOMEM;
538 
539 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
540 	if (retval)
541 		goto out;
542 
543 	retval = sched_setaffinity(pid, new_mask);
544 out:
545 	free_cpumask_var(new_mask);
546 	return retval;
547 }
548 
549 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
550 					     compat_ulong_t __user *user_mask_ptr)
551 {
552 	int ret;
553 	cpumask_var_t mask;
554 
555 	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
556 		return -EINVAL;
557 	if (len & (sizeof(compat_ulong_t)-1))
558 		return -EINVAL;
559 
560 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
561 		return -ENOMEM;
562 
563 	ret = sched_getaffinity(pid, mask);
564 	if (ret == 0) {
565 		size_t retlen = min_t(size_t, len, cpumask_size());
566 
567 		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
568 			ret = -EFAULT;
569 		else
570 			ret = retlen;
571 	}
572 	free_cpumask_var(mask);
573 
574 	return ret;
575 }
576 
577 int get_compat_itimerspec(struct itimerspec *dst,
578 			  const struct compat_itimerspec __user *src)
579 {
580 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
581 	    get_compat_timespec(&dst->it_value, &src->it_value))
582 		return -EFAULT;
583 	return 0;
584 }
585 
586 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
587 			  const struct itimerspec *src)
588 {
589 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
590 	    put_compat_timespec(&src->it_value, &dst->it_value))
591 		return -EFAULT;
592 	return 0;
593 }
594 
595 long compat_sys_timer_create(clockid_t which_clock,
596 			struct compat_sigevent __user *timer_event_spec,
597 			timer_t __user *created_timer_id)
598 {
599 	struct sigevent __user *event = NULL;
600 
601 	if (timer_event_spec) {
602 		struct sigevent kevent;
603 
604 		event = compat_alloc_user_space(sizeof(*event));
605 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
606 		    copy_to_user(event, &kevent, sizeof(*event)))
607 			return -EFAULT;
608 	}
609 
610 	return sys_timer_create(which_clock, event, created_timer_id);
611 }
612 
613 long compat_sys_timer_settime(timer_t timer_id, int flags,
614 			  struct compat_itimerspec __user *new,
615 			  struct compat_itimerspec __user *old)
616 {
617 	long err;
618 	mm_segment_t oldfs;
619 	struct itimerspec newts, oldts;
620 
621 	if (!new)
622 		return -EINVAL;
623 	if (get_compat_itimerspec(&newts, new))
624 		return -EFAULT;
625 	oldfs = get_fs();
626 	set_fs(KERNEL_DS);
627 	err = sys_timer_settime(timer_id, flags,
628 				(struct itimerspec __user *) &newts,
629 				(struct itimerspec __user *) &oldts);
630 	set_fs(oldfs);
631 	if (!err && old && put_compat_itimerspec(old, &oldts))
632 		return -EFAULT;
633 	return err;
634 }
635 
636 long compat_sys_timer_gettime(timer_t timer_id,
637 		struct compat_itimerspec __user *setting)
638 {
639 	long err;
640 	mm_segment_t oldfs;
641 	struct itimerspec ts;
642 
643 	oldfs = get_fs();
644 	set_fs(KERNEL_DS);
645 	err = sys_timer_gettime(timer_id,
646 				(struct itimerspec __user *) &ts);
647 	set_fs(oldfs);
648 	if (!err && put_compat_itimerspec(setting, &ts))
649 		return -EFAULT;
650 	return err;
651 }
652 
653 long compat_sys_clock_settime(clockid_t which_clock,
654 		struct compat_timespec __user *tp)
655 {
656 	long err;
657 	mm_segment_t oldfs;
658 	struct timespec ts;
659 
660 	if (get_compat_timespec(&ts, tp))
661 		return -EFAULT;
662 	oldfs = get_fs();
663 	set_fs(KERNEL_DS);
664 	err = sys_clock_settime(which_clock,
665 				(struct timespec __user *) &ts);
666 	set_fs(oldfs);
667 	return err;
668 }
669 
670 long compat_sys_clock_gettime(clockid_t which_clock,
671 		struct compat_timespec __user *tp)
672 {
673 	long err;
674 	mm_segment_t oldfs;
675 	struct timespec ts;
676 
677 	oldfs = get_fs();
678 	set_fs(KERNEL_DS);
679 	err = sys_clock_gettime(which_clock,
680 				(struct timespec __user *) &ts);
681 	set_fs(oldfs);
682 	if (!err && put_compat_timespec(&ts, tp))
683 		return -EFAULT;
684 	return err;
685 }
686 
687 long compat_sys_clock_adjtime(clockid_t which_clock,
688 		struct compat_timex __user *utp)
689 {
690 	struct timex txc;
691 	mm_segment_t oldfs;
692 	int err, ret;
693 
694 	err = compat_get_timex(&txc, utp);
695 	if (err)
696 		return err;
697 
698 	oldfs = get_fs();
699 	set_fs(KERNEL_DS);
700 	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
701 	set_fs(oldfs);
702 
703 	err = compat_put_timex(utp, &txc);
704 	if (err)
705 		return err;
706 
707 	return ret;
708 }
709 
710 long compat_sys_clock_getres(clockid_t which_clock,
711 		struct compat_timespec __user *tp)
712 {
713 	long err;
714 	mm_segment_t oldfs;
715 	struct timespec ts;
716 
717 	oldfs = get_fs();
718 	set_fs(KERNEL_DS);
719 	err = sys_clock_getres(which_clock,
720 			       (struct timespec __user *) &ts);
721 	set_fs(oldfs);
722 	if (!err && tp && put_compat_timespec(&ts, tp))
723 		return -EFAULT;
724 	return err;
725 }
726 
727 static long compat_clock_nanosleep_restart(struct restart_block *restart)
728 {
729 	long err;
730 	mm_segment_t oldfs;
731 	struct timespec tu;
732 	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
733 
734 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
735 	oldfs = get_fs();
736 	set_fs(KERNEL_DS);
737 	err = clock_nanosleep_restart(restart);
738 	set_fs(oldfs);
739 
740 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
741 	    put_compat_timespec(&tu, rmtp))
742 		return -EFAULT;
743 
744 	if (err == -ERESTART_RESTARTBLOCK) {
745 		restart->fn = compat_clock_nanosleep_restart;
746 		restart->nanosleep.compat_rmtp = rmtp;
747 	}
748 	return err;
749 }
750 
751 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
752 			    struct compat_timespec __user *rqtp,
753 			    struct compat_timespec __user *rmtp)
754 {
755 	long err;
756 	mm_segment_t oldfs;
757 	struct timespec in, out;
758 	struct restart_block *restart;
759 
760 	if (get_compat_timespec(&in, rqtp))
761 		return -EFAULT;
762 
763 	oldfs = get_fs();
764 	set_fs(KERNEL_DS);
765 	err = sys_clock_nanosleep(which_clock, flags,
766 				  (struct timespec __user *) &in,
767 				  (struct timespec __user *) &out);
768 	set_fs(oldfs);
769 
770 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
771 	    put_compat_timespec(&out, rmtp))
772 		return -EFAULT;
773 
774 	if (err == -ERESTART_RESTARTBLOCK) {
775 		restart = &current_thread_info()->restart_block;
776 		restart->fn = compat_clock_nanosleep_restart;
777 		restart->nanosleep.compat_rmtp = rmtp;
778 	}
779 	return err;
780 }
781 
782 /*
783  * We currently only need the following fields from the sigevent
784  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
785  * sigev_notify_thread_id).  The others are handled in user mode.
786  * We also assume that copying sigev_value.sival_int is sufficient
787  * to keep all the bits of sigev_value.sival_ptr intact.
788  */
789 int get_compat_sigevent(struct sigevent *event,
790 		const struct compat_sigevent __user *u_event)
791 {
792 	memset(event, 0, sizeof(*event));
793 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
794 		__get_user(event->sigev_value.sival_int,
795 			&u_event->sigev_value.sival_int) ||
796 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
797 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
798 		__get_user(event->sigev_notify_thread_id,
799 			&u_event->sigev_notify_thread_id))
800 		? -EFAULT : 0;
801 }
802 
803 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
804 		       unsigned long bitmap_size)
805 {
806 	int i, j;
807 	unsigned long m;
808 	compat_ulong_t um;
809 	unsigned long nr_compat_longs;
810 
811 	/* align bitmap up to nearest compat_long_t boundary */
812 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
813 
814 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
815 		return -EFAULT;
816 
817 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
818 
819 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
820 		m = 0;
821 
822 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
823 			/*
824 			 * We dont want to read past the end of the userspace
825 			 * bitmap. We must however ensure the end of the
826 			 * kernel bitmap is zeroed.
827 			 */
828 			if (nr_compat_longs-- > 0) {
829 				if (__get_user(um, umask))
830 					return -EFAULT;
831 			} else {
832 				um = 0;
833 			}
834 
835 			umask++;
836 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
837 		}
838 		*mask++ = m;
839 	}
840 
841 	return 0;
842 }
843 
844 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
845 		       unsigned long bitmap_size)
846 {
847 	int i, j;
848 	unsigned long m;
849 	compat_ulong_t um;
850 	unsigned long nr_compat_longs;
851 
852 	/* align bitmap up to nearest compat_long_t boundary */
853 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
854 
855 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
856 		return -EFAULT;
857 
858 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
859 
860 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
861 		m = *mask++;
862 
863 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
864 			um = m;
865 
866 			/*
867 			 * We dont want to write past the end of the userspace
868 			 * bitmap.
869 			 */
870 			if (nr_compat_longs-- > 0) {
871 				if (__put_user(um, umask))
872 					return -EFAULT;
873 			}
874 
875 			umask++;
876 			m >>= 4*sizeof(um);
877 			m >>= 4*sizeof(um);
878 		}
879 	}
880 
881 	return 0;
882 }
883 
884 void
885 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
886 {
887 	switch (_NSIG_WORDS) {
888 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
889 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
890 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
891 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
892 	}
893 }
894 EXPORT_SYMBOL_GPL(sigset_from_compat);
895 
896 asmlinkage long
897 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
898 		struct compat_siginfo __user *uinfo,
899 		struct compat_timespec __user *uts, compat_size_t sigsetsize)
900 {
901 	compat_sigset_t s32;
902 	sigset_t s;
903 	struct timespec t;
904 	siginfo_t info;
905 	long ret;
906 
907 	if (sigsetsize != sizeof(sigset_t))
908 		return -EINVAL;
909 
910 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
911 		return -EFAULT;
912 	sigset_from_compat(&s, &s32);
913 
914 	if (uts) {
915 		if (get_compat_timespec(&t, uts))
916 			return -EFAULT;
917 	}
918 
919 	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
920 
921 	if (ret > 0 && uinfo) {
922 		if (copy_siginfo_to_user32(uinfo, &info))
923 			ret = -EFAULT;
924 	}
925 
926 	return ret;
927 
928 }
929 
930 asmlinkage long
931 compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig,
932 			     struct compat_siginfo __user *uinfo)
933 {
934 	siginfo_t info;
935 
936 	if (copy_siginfo_from_user32(&info, uinfo))
937 		return -EFAULT;
938 	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
939 }
940 
941 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
942 
943 /* compat_time_t is a 32 bit "long" and needs to get converted. */
944 
945 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
946 {
947 	compat_time_t i;
948 	struct timeval tv;
949 
950 	do_gettimeofday(&tv);
951 	i = tv.tv_sec;
952 
953 	if (tloc) {
954 		if (put_user(i,tloc))
955 			return -EFAULT;
956 	}
957 	force_successful_syscall_return();
958 	return i;
959 }
960 
961 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
962 {
963 	struct timespec tv;
964 	int err;
965 
966 	if (get_user(tv.tv_sec, tptr))
967 		return -EFAULT;
968 
969 	tv.tv_nsec = 0;
970 
971 	err = security_settime(&tv, NULL);
972 	if (err)
973 		return err;
974 
975 	do_settimeofday(&tv);
976 	return 0;
977 }
978 
979 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
980 
981 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
982 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
983 {
984 	sigset_t newset;
985 	compat_sigset_t newset32;
986 
987 	/* XXX: Don't preclude handling different sized sigset_t's.  */
988 	if (sigsetsize != sizeof(sigset_t))
989 		return -EINVAL;
990 
991 	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
992 		return -EFAULT;
993 	sigset_from_compat(&newset, &newset32);
994 	sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
995 
996 	current->saved_sigmask = current->blocked;
997 	set_current_blocked(&newset);
998 
999 	current->state = TASK_INTERRUPTIBLE;
1000 	schedule();
1001 	set_restore_sigmask();
1002 	return -ERESTARTNOHAND;
1003 }
1004 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
1005 
1006 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
1007 {
1008 	struct timex txc;
1009 	int err, ret;
1010 
1011 	err = compat_get_timex(&txc, utp);
1012 	if (err)
1013 		return err;
1014 
1015 	ret = do_adjtimex(&txc);
1016 
1017 	err = compat_put_timex(utp, &txc);
1018 	if (err)
1019 		return err;
1020 
1021 	return ret;
1022 }
1023 
1024 #ifdef CONFIG_NUMA
1025 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1026 		compat_uptr_t __user *pages32,
1027 		const int __user *nodes,
1028 		int __user *status,
1029 		int flags)
1030 {
1031 	const void __user * __user *pages;
1032 	int i;
1033 
1034 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1035 	for (i = 0; i < nr_pages; i++) {
1036 		compat_uptr_t p;
1037 
1038 		if (get_user(p, pages32 + i) ||
1039 			put_user(compat_ptr(p), pages + i))
1040 			return -EFAULT;
1041 	}
1042 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1043 }
1044 
1045 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1046 			compat_ulong_t maxnode,
1047 			const compat_ulong_t __user *old_nodes,
1048 			const compat_ulong_t __user *new_nodes)
1049 {
1050 	unsigned long __user *old = NULL;
1051 	unsigned long __user *new = NULL;
1052 	nodemask_t tmp_mask;
1053 	unsigned long nr_bits;
1054 	unsigned long size;
1055 
1056 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1057 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1058 	if (old_nodes) {
1059 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1060 			return -EFAULT;
1061 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1062 		if (new_nodes)
1063 			new = old + size / sizeof(unsigned long);
1064 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1065 			return -EFAULT;
1066 	}
1067 	if (new_nodes) {
1068 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1069 			return -EFAULT;
1070 		if (new == NULL)
1071 			new = compat_alloc_user_space(size);
1072 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1073 			return -EFAULT;
1074 	}
1075 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1076 }
1077 #endif
1078 
1079 struct compat_sysinfo {
1080 	s32 uptime;
1081 	u32 loads[3];
1082 	u32 totalram;
1083 	u32 freeram;
1084 	u32 sharedram;
1085 	u32 bufferram;
1086 	u32 totalswap;
1087 	u32 freeswap;
1088 	u16 procs;
1089 	u16 pad;
1090 	u32 totalhigh;
1091 	u32 freehigh;
1092 	u32 mem_unit;
1093 	char _f[20-2*sizeof(u32)-sizeof(int)];
1094 };
1095 
1096 asmlinkage long
1097 compat_sys_sysinfo(struct compat_sysinfo __user *info)
1098 {
1099 	struct sysinfo s;
1100 
1101 	do_sysinfo(&s);
1102 
1103 	/* Check to see if any memory value is too large for 32-bit and scale
1104 	 *  down if needed
1105 	 */
1106 	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
1107 		int bitcount = 0;
1108 
1109 		while (s.mem_unit < PAGE_SIZE) {
1110 			s.mem_unit <<= 1;
1111 			bitcount++;
1112 		}
1113 
1114 		s.totalram >>= bitcount;
1115 		s.freeram >>= bitcount;
1116 		s.sharedram >>= bitcount;
1117 		s.bufferram >>= bitcount;
1118 		s.totalswap >>= bitcount;
1119 		s.freeswap >>= bitcount;
1120 		s.totalhigh >>= bitcount;
1121 		s.freehigh >>= bitcount;
1122 	}
1123 
1124 	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
1125 	    __put_user (s.uptime, &info->uptime) ||
1126 	    __put_user (s.loads[0], &info->loads[0]) ||
1127 	    __put_user (s.loads[1], &info->loads[1]) ||
1128 	    __put_user (s.loads[2], &info->loads[2]) ||
1129 	    __put_user (s.totalram, &info->totalram) ||
1130 	    __put_user (s.freeram, &info->freeram) ||
1131 	    __put_user (s.sharedram, &info->sharedram) ||
1132 	    __put_user (s.bufferram, &info->bufferram) ||
1133 	    __put_user (s.totalswap, &info->totalswap) ||
1134 	    __put_user (s.freeswap, &info->freeswap) ||
1135 	    __put_user (s.procs, &info->procs) ||
1136 	    __put_user (s.totalhigh, &info->totalhigh) ||
1137 	    __put_user (s.freehigh, &info->freehigh) ||
1138 	    __put_user (s.mem_unit, &info->mem_unit))
1139 		return -EFAULT;
1140 
1141 	return 0;
1142 }
1143 
1144 /*
1145  * Allocate user-space memory for the duration of a single system call,
1146  * in order to marshall parameters inside a compat thunk.
1147  */
1148 void __user *compat_alloc_user_space(unsigned long len)
1149 {
1150 	void __user *ptr;
1151 
1152 	/* If len would occupy more than half of the entire compat space... */
1153 	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1154 		return NULL;
1155 
1156 	ptr = arch_compat_alloc_user_space(len);
1157 
1158 	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1159 		return NULL;
1160 
1161 	return ptr;
1162 }
1163 EXPORT_SYMBOL_GPL(compat_alloc_user_space);
1164