xref: /openbmc/linux/kernel/compat.c (revision c4ee0af3) 
1 /*
2  *  linux/kernel/compat.c
3  *
4  *  Kernel compatibililty routines for e.g. 32 bit syscall support
5  *  on 64 bit kernels.
6  *
7  *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2 as
11  *  published by the Free Software Foundation.
12  */
13 
14 #include <linux/linkage.h>
15 #include <linux/compat.h>
16 #include <linux/errno.h>
17 #include <linux/time.h>
18 #include <linux/signal.h>
19 #include <linux/sched.h>	/* for MAX_SCHEDULE_TIMEOUT */
20 #include <linux/syscalls.h>
21 #include <linux/unistd.h>
22 #include <linux/security.h>
23 #include <linux/timex.h>
24 #include <linux/export.h>
25 #include <linux/migrate.h>
26 #include <linux/posix-timers.h>
27 #include <linux/times.h>
28 #include <linux/ptrace.h>
29 #include <linux/gfp.h>
30 
31 #include <asm/uaccess.h>
32 
33 /*
34  * Get/set struct timeval with struct timespec on the native side
35  */
36 static int compat_get_timeval_convert(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_convert(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_convert(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_convert(&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_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
149 {
150 	return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
151 			__get_user(tv->tv_sec, &ctv->tv_sec) ||
152 			__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
153 }
154 EXPORT_SYMBOL_GPL(get_compat_timeval);
155 
156 int put_compat_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
157 {
158 	return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
159 			__put_user(tv->tv_sec, &ctv->tv_sec) ||
160 			__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
161 }
162 EXPORT_SYMBOL_GPL(put_compat_timeval);
163 
164 int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
165 {
166 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
167 			__get_user(ts->tv_sec, &cts->tv_sec) ||
168 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
169 }
170 EXPORT_SYMBOL_GPL(get_compat_timespec);
171 
172 int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
173 {
174 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
175 			__put_user(ts->tv_sec, &cts->tv_sec) ||
176 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
177 }
178 EXPORT_SYMBOL_GPL(put_compat_timespec);
179 
180 int compat_get_timeval(struct timeval *tv, const void __user *utv)
181 {
182 	if (COMPAT_USE_64BIT_TIME)
183 		return copy_from_user(tv, utv, sizeof *tv) ? -EFAULT : 0;
184 	else
185 		return get_compat_timeval(tv, utv);
186 }
187 EXPORT_SYMBOL_GPL(compat_get_timeval);
188 
189 int compat_put_timeval(const struct timeval *tv, void __user *utv)
190 {
191 	if (COMPAT_USE_64BIT_TIME)
192 		return copy_to_user(utv, tv, sizeof *tv) ? -EFAULT : 0;
193 	else
194 		return put_compat_timeval(tv, utv);
195 }
196 EXPORT_SYMBOL_GPL(compat_put_timeval);
197 
198 int compat_get_timespec(struct timespec *ts, const void __user *uts)
199 {
200 	if (COMPAT_USE_64BIT_TIME)
201 		return copy_from_user(ts, uts, sizeof *ts) ? -EFAULT : 0;
202 	else
203 		return get_compat_timespec(ts, uts);
204 }
205 EXPORT_SYMBOL_GPL(compat_get_timespec);
206 
207 int compat_put_timespec(const struct timespec *ts, void __user *uts)
208 {
209 	if (COMPAT_USE_64BIT_TIME)
210 		return copy_to_user(uts, ts, sizeof *ts) ? -EFAULT : 0;
211 	else
212 		return put_compat_timespec(ts, uts);
213 }
214 EXPORT_SYMBOL_GPL(compat_put_timespec);
215 
216 static long compat_nanosleep_restart(struct restart_block *restart)
217 {
218 	struct compat_timespec __user *rmtp;
219 	struct timespec rmt;
220 	mm_segment_t oldfs;
221 	long ret;
222 
223 	restart->nanosleep.rmtp = (struct timespec __user *) &rmt;
224 	oldfs = get_fs();
225 	set_fs(KERNEL_DS);
226 	ret = hrtimer_nanosleep_restart(restart);
227 	set_fs(oldfs);
228 
229 	if (ret) {
230 		rmtp = restart->nanosleep.compat_rmtp;
231 
232 		if (rmtp && put_compat_timespec(&rmt, rmtp))
233 			return -EFAULT;
234 	}
235 
236 	return ret;
237 }
238 
239 asmlinkage long compat_sys_nanosleep(struct compat_timespec __user *rqtp,
240 				     struct compat_timespec __user *rmtp)
241 {
242 	struct timespec tu, rmt;
243 	mm_segment_t oldfs;
244 	long ret;
245 
246 	if (get_compat_timespec(&tu, rqtp))
247 		return -EFAULT;
248 
249 	if (!timespec_valid(&tu))
250 		return -EINVAL;
251 
252 	oldfs = get_fs();
253 	set_fs(KERNEL_DS);
254 	ret = hrtimer_nanosleep(&tu,
255 				rmtp ? (struct timespec __user *)&rmt : NULL,
256 				HRTIMER_MODE_REL, CLOCK_MONOTONIC);
257 	set_fs(oldfs);
258 
259 	if (ret) {
260 		struct restart_block *restart
261 			= &current_thread_info()->restart_block;
262 
263 		restart->fn = compat_nanosleep_restart;
264 		restart->nanosleep.compat_rmtp = rmtp;
265 
266 		if (rmtp && put_compat_timespec(&rmt, rmtp))
267 			return -EFAULT;
268 	}
269 
270 	return ret;
271 }
272 
273 static inline long get_compat_itimerval(struct itimerval *o,
274 		struct compat_itimerval __user *i)
275 {
276 	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
277 		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
278 		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
279 		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
280 		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
281 }
282 
283 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
284 		struct itimerval *i)
285 {
286 	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
287 		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
288 		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
289 		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
290 		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
291 }
292 
293 COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
294 		struct compat_itimerval __user *, it)
295 {
296 	struct itimerval kit;
297 	int error;
298 
299 	error = do_getitimer(which, &kit);
300 	if (!error && put_compat_itimerval(it, &kit))
301 		error = -EFAULT;
302 	return error;
303 }
304 
305 COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
306 		struct compat_itimerval __user *, in,
307 		struct compat_itimerval __user *, out)
308 {
309 	struct itimerval kin, kout;
310 	int error;
311 
312 	if (in) {
313 		if (get_compat_itimerval(&kin, in))
314 			return -EFAULT;
315 	} else
316 		memset(&kin, 0, sizeof(kin));
317 
318 	error = do_setitimer(which, &kin, out ? &kout : NULL);
319 	if (error || !out)
320 		return error;
321 	if (put_compat_itimerval(out, &kout))
322 		return -EFAULT;
323 	return 0;
324 }
325 
326 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
327 {
328 	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
329 }
330 
331 asmlinkage long compat_sys_times(struct compat_tms __user *tbuf)
332 {
333 	if (tbuf) {
334 		struct tms tms;
335 		struct compat_tms tmp;
336 
337 		do_sys_times(&tms);
338 		/* Convert our struct tms to the compat version. */
339 		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
340 		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
341 		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
342 		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
343 		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
344 			return -EFAULT;
345 	}
346 	force_successful_syscall_return();
347 	return compat_jiffies_to_clock_t(jiffies);
348 }
349 
350 #ifdef __ARCH_WANT_SYS_SIGPENDING
351 
352 /*
353  * Assumption: old_sigset_t and compat_old_sigset_t are both
354  * types that can be passed to put_user()/get_user().
355  */
356 
357 asmlinkage long compat_sys_sigpending(compat_old_sigset_t __user *set)
358 {
359 	old_sigset_t s;
360 	long ret;
361 	mm_segment_t old_fs = get_fs();
362 
363 	set_fs(KERNEL_DS);
364 	ret = sys_sigpending((old_sigset_t __user *) &s);
365 	set_fs(old_fs);
366 	if (ret == 0)
367 		ret = put_user(s, set);
368 	return ret;
369 }
370 
371 #endif
372 
373 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
374 
375 /*
376  * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
377  * blocked set of signals to the supplied signal set
378  */
379 static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
380 {
381 	memcpy(blocked->sig, &set, sizeof(set));
382 }
383 
384 COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
385 		       compat_old_sigset_t __user *, nset,
386 		       compat_old_sigset_t __user *, oset)
387 {
388 	old_sigset_t old_set, new_set;
389 	sigset_t new_blocked;
390 
391 	old_set = current->blocked.sig[0];
392 
393 	if (nset) {
394 		if (get_user(new_set, nset))
395 			return -EFAULT;
396 		new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
397 
398 		new_blocked = current->blocked;
399 
400 		switch (how) {
401 		case SIG_BLOCK:
402 			sigaddsetmask(&new_blocked, new_set);
403 			break;
404 		case SIG_UNBLOCK:
405 			sigdelsetmask(&new_blocked, new_set);
406 			break;
407 		case SIG_SETMASK:
408 			compat_sig_setmask(&new_blocked, new_set);
409 			break;
410 		default:
411 			return -EINVAL;
412 		}
413 
414 		set_current_blocked(&new_blocked);
415 	}
416 
417 	if (oset) {
418 		if (put_user(old_set, oset))
419 			return -EFAULT;
420 	}
421 
422 	return 0;
423 }
424 
425 #endif
426 
427 asmlinkage long compat_sys_setrlimit(unsigned int resource,
428 		struct compat_rlimit __user *rlim)
429 {
430 	struct rlimit r;
431 
432 	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
433 	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
434 	    __get_user(r.rlim_max, &rlim->rlim_max))
435 		return -EFAULT;
436 
437 	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
438 		r.rlim_cur = RLIM_INFINITY;
439 	if (r.rlim_max == COMPAT_RLIM_INFINITY)
440 		r.rlim_max = RLIM_INFINITY;
441 	return do_prlimit(current, resource, &r, NULL);
442 }
443 
444 #ifdef COMPAT_RLIM_OLD_INFINITY
445 
446 asmlinkage long compat_sys_old_getrlimit(unsigned int resource,
447 		struct compat_rlimit __user *rlim)
448 {
449 	struct rlimit r;
450 	int ret;
451 	mm_segment_t old_fs = get_fs();
452 
453 	set_fs(KERNEL_DS);
454 	ret = sys_old_getrlimit(resource, &r);
455 	set_fs(old_fs);
456 
457 	if (!ret) {
458 		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
459 			r.rlim_cur = COMPAT_RLIM_INFINITY;
460 		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
461 			r.rlim_max = COMPAT_RLIM_INFINITY;
462 
463 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
464 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
465 		    __put_user(r.rlim_max, &rlim->rlim_max))
466 			return -EFAULT;
467 	}
468 	return ret;
469 }
470 
471 #endif
472 
473 asmlinkage long compat_sys_getrlimit(unsigned int resource,
474 		struct compat_rlimit __user *rlim)
475 {
476 	struct rlimit r;
477 	int ret;
478 
479 	ret = do_prlimit(current, resource, NULL, &r);
480 	if (!ret) {
481 		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
482 			r.rlim_cur = COMPAT_RLIM_INFINITY;
483 		if (r.rlim_max > COMPAT_RLIM_INFINITY)
484 			r.rlim_max = COMPAT_RLIM_INFINITY;
485 
486 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
487 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
488 		    __put_user(r.rlim_max, &rlim->rlim_max))
489 			return -EFAULT;
490 	}
491 	return ret;
492 }
493 
494 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
495 {
496 	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
497 	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
498 	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
499 	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
500 	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
501 	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
502 	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
503 	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
504 	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
505 	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
506 	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
507 	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
508 	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
509 	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
510 	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
511 	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
512 	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
513 	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
514 	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
515 		return -EFAULT;
516 	return 0;
517 }
518 
519 COMPAT_SYSCALL_DEFINE4(wait4,
520 	compat_pid_t, pid,
521 	compat_uint_t __user *, stat_addr,
522 	int, options,
523 	struct compat_rusage __user *, ru)
524 {
525 	if (!ru) {
526 		return sys_wait4(pid, stat_addr, options, NULL);
527 	} else {
528 		struct rusage r;
529 		int ret;
530 		unsigned int status;
531 		mm_segment_t old_fs = get_fs();
532 
533 		set_fs (KERNEL_DS);
534 		ret = sys_wait4(pid,
535 				(stat_addr ?
536 				 (unsigned int __user *) &status : NULL),
537 				options, (struct rusage __user *) &r);
538 		set_fs (old_fs);
539 
540 		if (ret > 0) {
541 			if (put_compat_rusage(&r, ru))
542 				return -EFAULT;
543 			if (stat_addr && put_user(status, stat_addr))
544 				return -EFAULT;
545 		}
546 		return ret;
547 	}
548 }
549 
550 COMPAT_SYSCALL_DEFINE5(waitid,
551 		int, which, compat_pid_t, pid,
552 		struct compat_siginfo __user *, uinfo, int, options,
553 		struct compat_rusage __user *, uru)
554 {
555 	siginfo_t info;
556 	struct rusage ru;
557 	long ret;
558 	mm_segment_t old_fs = get_fs();
559 
560 	memset(&info, 0, sizeof(info));
561 
562 	set_fs(KERNEL_DS);
563 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
564 			 uru ? (struct rusage __user *)&ru : NULL);
565 	set_fs(old_fs);
566 
567 	if ((ret < 0) || (info.si_signo == 0))
568 		return ret;
569 
570 	if (uru) {
571 		/* sys_waitid() overwrites everything in ru */
572 		if (COMPAT_USE_64BIT_TIME)
573 			ret = copy_to_user(uru, &ru, sizeof(ru));
574 		else
575 			ret = put_compat_rusage(&ru, uru);
576 		if (ret)
577 			return -EFAULT;
578 	}
579 
580 	BUG_ON(info.si_code & __SI_MASK);
581 	info.si_code |= __SI_CHLD;
582 	return copy_siginfo_to_user32(uinfo, &info);
583 }
584 
585 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
586 				    unsigned len, struct cpumask *new_mask)
587 {
588 	unsigned long *k;
589 
590 	if (len < cpumask_size())
591 		memset(new_mask, 0, cpumask_size());
592 	else if (len > cpumask_size())
593 		len = cpumask_size();
594 
595 	k = cpumask_bits(new_mask);
596 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
597 }
598 
599 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
600 					     unsigned int len,
601 					     compat_ulong_t __user *user_mask_ptr)
602 {
603 	cpumask_var_t new_mask;
604 	int retval;
605 
606 	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
607 		return -ENOMEM;
608 
609 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
610 	if (retval)
611 		goto out;
612 
613 	retval = sched_setaffinity(pid, new_mask);
614 out:
615 	free_cpumask_var(new_mask);
616 	return retval;
617 }
618 
619 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
620 					     compat_ulong_t __user *user_mask_ptr)
621 {
622 	int ret;
623 	cpumask_var_t mask;
624 
625 	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
626 		return -EINVAL;
627 	if (len & (sizeof(compat_ulong_t)-1))
628 		return -EINVAL;
629 
630 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
631 		return -ENOMEM;
632 
633 	ret = sched_getaffinity(pid, mask);
634 	if (ret == 0) {
635 		size_t retlen = min_t(size_t, len, cpumask_size());
636 
637 		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
638 			ret = -EFAULT;
639 		else
640 			ret = retlen;
641 	}
642 	free_cpumask_var(mask);
643 
644 	return ret;
645 }
646 
647 int get_compat_itimerspec(struct itimerspec *dst,
648 			  const struct compat_itimerspec __user *src)
649 {
650 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
651 	    get_compat_timespec(&dst->it_value, &src->it_value))
652 		return -EFAULT;
653 	return 0;
654 }
655 
656 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
657 			  const struct itimerspec *src)
658 {
659 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
660 	    put_compat_timespec(&src->it_value, &dst->it_value))
661 		return -EFAULT;
662 	return 0;
663 }
664 
665 long compat_sys_timer_create(clockid_t which_clock,
666 			struct compat_sigevent __user *timer_event_spec,
667 			timer_t __user *created_timer_id)
668 {
669 	struct sigevent __user *event = NULL;
670 
671 	if (timer_event_spec) {
672 		struct sigevent kevent;
673 
674 		event = compat_alloc_user_space(sizeof(*event));
675 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
676 		    copy_to_user(event, &kevent, sizeof(*event)))
677 			return -EFAULT;
678 	}
679 
680 	return sys_timer_create(which_clock, event, created_timer_id);
681 }
682 
683 long compat_sys_timer_settime(timer_t timer_id, int flags,
684 			  struct compat_itimerspec __user *new,
685 			  struct compat_itimerspec __user *old)
686 {
687 	long err;
688 	mm_segment_t oldfs;
689 	struct itimerspec newts, oldts;
690 
691 	if (!new)
692 		return -EINVAL;
693 	if (get_compat_itimerspec(&newts, new))
694 		return -EFAULT;
695 	oldfs = get_fs();
696 	set_fs(KERNEL_DS);
697 	err = sys_timer_settime(timer_id, flags,
698 				(struct itimerspec __user *) &newts,
699 				(struct itimerspec __user *) &oldts);
700 	set_fs(oldfs);
701 	if (!err && old && put_compat_itimerspec(old, &oldts))
702 		return -EFAULT;
703 	return err;
704 }
705 
706 long compat_sys_timer_gettime(timer_t timer_id,
707 		struct compat_itimerspec __user *setting)
708 {
709 	long err;
710 	mm_segment_t oldfs;
711 	struct itimerspec ts;
712 
713 	oldfs = get_fs();
714 	set_fs(KERNEL_DS);
715 	err = sys_timer_gettime(timer_id,
716 				(struct itimerspec __user *) &ts);
717 	set_fs(oldfs);
718 	if (!err && put_compat_itimerspec(setting, &ts))
719 		return -EFAULT;
720 	return err;
721 }
722 
723 long compat_sys_clock_settime(clockid_t which_clock,
724 		struct compat_timespec __user *tp)
725 {
726 	long err;
727 	mm_segment_t oldfs;
728 	struct timespec ts;
729 
730 	if (get_compat_timespec(&ts, tp))
731 		return -EFAULT;
732 	oldfs = get_fs();
733 	set_fs(KERNEL_DS);
734 	err = sys_clock_settime(which_clock,
735 				(struct timespec __user *) &ts);
736 	set_fs(oldfs);
737 	return err;
738 }
739 
740 long compat_sys_clock_gettime(clockid_t which_clock,
741 		struct compat_timespec __user *tp)
742 {
743 	long err;
744 	mm_segment_t oldfs;
745 	struct timespec ts;
746 
747 	oldfs = get_fs();
748 	set_fs(KERNEL_DS);
749 	err = sys_clock_gettime(which_clock,
750 				(struct timespec __user *) &ts);
751 	set_fs(oldfs);
752 	if (!err && put_compat_timespec(&ts, tp))
753 		return -EFAULT;
754 	return err;
755 }
756 
757 long compat_sys_clock_adjtime(clockid_t which_clock,
758 		struct compat_timex __user *utp)
759 {
760 	struct timex txc;
761 	mm_segment_t oldfs;
762 	int err, ret;
763 
764 	err = compat_get_timex(&txc, utp);
765 	if (err)
766 		return err;
767 
768 	oldfs = get_fs();
769 	set_fs(KERNEL_DS);
770 	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
771 	set_fs(oldfs);
772 
773 	err = compat_put_timex(utp, &txc);
774 	if (err)
775 		return err;
776 
777 	return ret;
778 }
779 
780 long compat_sys_clock_getres(clockid_t which_clock,
781 		struct compat_timespec __user *tp)
782 {
783 	long err;
784 	mm_segment_t oldfs;
785 	struct timespec ts;
786 
787 	oldfs = get_fs();
788 	set_fs(KERNEL_DS);
789 	err = sys_clock_getres(which_clock,
790 			       (struct timespec __user *) &ts);
791 	set_fs(oldfs);
792 	if (!err && tp && put_compat_timespec(&ts, tp))
793 		return -EFAULT;
794 	return err;
795 }
796 
797 static long compat_clock_nanosleep_restart(struct restart_block *restart)
798 {
799 	long err;
800 	mm_segment_t oldfs;
801 	struct timespec tu;
802 	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
803 
804 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
805 	oldfs = get_fs();
806 	set_fs(KERNEL_DS);
807 	err = clock_nanosleep_restart(restart);
808 	set_fs(oldfs);
809 
810 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
811 	    put_compat_timespec(&tu, rmtp))
812 		return -EFAULT;
813 
814 	if (err == -ERESTART_RESTARTBLOCK) {
815 		restart->fn = compat_clock_nanosleep_restart;
816 		restart->nanosleep.compat_rmtp = rmtp;
817 	}
818 	return err;
819 }
820 
821 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
822 			    struct compat_timespec __user *rqtp,
823 			    struct compat_timespec __user *rmtp)
824 {
825 	long err;
826 	mm_segment_t oldfs;
827 	struct timespec in, out;
828 	struct restart_block *restart;
829 
830 	if (get_compat_timespec(&in, rqtp))
831 		return -EFAULT;
832 
833 	oldfs = get_fs();
834 	set_fs(KERNEL_DS);
835 	err = sys_clock_nanosleep(which_clock, flags,
836 				  (struct timespec __user *) &in,
837 				  (struct timespec __user *) &out);
838 	set_fs(oldfs);
839 
840 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
841 	    put_compat_timespec(&out, rmtp))
842 		return -EFAULT;
843 
844 	if (err == -ERESTART_RESTARTBLOCK) {
845 		restart = &current_thread_info()->restart_block;
846 		restart->fn = compat_clock_nanosleep_restart;
847 		restart->nanosleep.compat_rmtp = rmtp;
848 	}
849 	return err;
850 }
851 
852 /*
853  * We currently only need the following fields from the sigevent
854  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
855  * sigev_notify_thread_id).  The others are handled in user mode.
856  * We also assume that copying sigev_value.sival_int is sufficient
857  * to keep all the bits of sigev_value.sival_ptr intact.
858  */
859 int get_compat_sigevent(struct sigevent *event,
860 		const struct compat_sigevent __user *u_event)
861 {
862 	memset(event, 0, sizeof(*event));
863 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
864 		__get_user(event->sigev_value.sival_int,
865 			&u_event->sigev_value.sival_int) ||
866 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
867 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
868 		__get_user(event->sigev_notify_thread_id,
869 			&u_event->sigev_notify_thread_id))
870 		? -EFAULT : 0;
871 }
872 
873 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
874 		       unsigned long bitmap_size)
875 {
876 	int i, j;
877 	unsigned long m;
878 	compat_ulong_t um;
879 	unsigned long nr_compat_longs;
880 
881 	/* align bitmap up to nearest compat_long_t boundary */
882 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
883 
884 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
885 		return -EFAULT;
886 
887 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
888 
889 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
890 		m = 0;
891 
892 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
893 			/*
894 			 * We dont want to read past the end of the userspace
895 			 * bitmap. We must however ensure the end of the
896 			 * kernel bitmap is zeroed.
897 			 */
898 			if (nr_compat_longs-- > 0) {
899 				if (__get_user(um, umask))
900 					return -EFAULT;
901 			} else {
902 				um = 0;
903 			}
904 
905 			umask++;
906 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
907 		}
908 		*mask++ = m;
909 	}
910 
911 	return 0;
912 }
913 
914 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
915 		       unsigned long bitmap_size)
916 {
917 	int i, j;
918 	unsigned long m;
919 	compat_ulong_t um;
920 	unsigned long nr_compat_longs;
921 
922 	/* align bitmap up to nearest compat_long_t boundary */
923 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
924 
925 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
926 		return -EFAULT;
927 
928 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
929 
930 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
931 		m = *mask++;
932 
933 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
934 			um = m;
935 
936 			/*
937 			 * We dont want to write past the end of the userspace
938 			 * bitmap.
939 			 */
940 			if (nr_compat_longs-- > 0) {
941 				if (__put_user(um, umask))
942 					return -EFAULT;
943 			}
944 
945 			umask++;
946 			m >>= 4*sizeof(um);
947 			m >>= 4*sizeof(um);
948 		}
949 	}
950 
951 	return 0;
952 }
953 
954 void
955 sigset_from_compat(sigset_t *set, const compat_sigset_t *compat)
956 {
957 	switch (_NSIG_WORDS) {
958 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
959 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
960 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
961 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
962 	}
963 }
964 EXPORT_SYMBOL_GPL(sigset_from_compat);
965 
966 void
967 sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
968 {
969 	switch (_NSIG_WORDS) {
970 	case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
971 	case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
972 	case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
973 	case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
974 	}
975 }
976 
977 COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
978 		struct compat_siginfo __user *, uinfo,
979 		struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
980 {
981 	compat_sigset_t s32;
982 	sigset_t s;
983 	struct timespec t;
984 	siginfo_t info;
985 	long ret;
986 
987 	if (sigsetsize != sizeof(sigset_t))
988 		return -EINVAL;
989 
990 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
991 		return -EFAULT;
992 	sigset_from_compat(&s, &s32);
993 
994 	if (uts) {
995 		if (compat_get_timespec(&t, uts))
996 			return -EFAULT;
997 	}
998 
999 	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1000 
1001 	if (ret > 0 && uinfo) {
1002 		if (copy_siginfo_to_user32(uinfo, &info))
1003 			ret = -EFAULT;
1004 	}
1005 
1006 	return ret;
1007 }
1008 
1009 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1010 
1011 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1012 
1013 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
1014 {
1015 	compat_time_t i;
1016 	struct timeval tv;
1017 
1018 	do_gettimeofday(&tv);
1019 	i = tv.tv_sec;
1020 
1021 	if (tloc) {
1022 		if (put_user(i,tloc))
1023 			return -EFAULT;
1024 	}
1025 	force_successful_syscall_return();
1026 	return i;
1027 }
1028 
1029 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
1030 {
1031 	struct timespec tv;
1032 	int err;
1033 
1034 	if (get_user(tv.tv_sec, tptr))
1035 		return -EFAULT;
1036 
1037 	tv.tv_nsec = 0;
1038 
1039 	err = security_settime(&tv, NULL);
1040 	if (err)
1041 		return err;
1042 
1043 	do_settimeofday(&tv);
1044 	return 0;
1045 }
1046 
1047 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1048 
1049 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
1050 {
1051 	struct timex txc;
1052 	int err, ret;
1053 
1054 	err = compat_get_timex(&txc, utp);
1055 	if (err)
1056 		return err;
1057 
1058 	ret = do_adjtimex(&txc);
1059 
1060 	err = compat_put_timex(utp, &txc);
1061 	if (err)
1062 		return err;
1063 
1064 	return ret;
1065 }
1066 
1067 #ifdef CONFIG_NUMA
1068 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1069 		compat_uptr_t __user *pages32,
1070 		const int __user *nodes,
1071 		int __user *status,
1072 		int flags)
1073 {
1074 	const void __user * __user *pages;
1075 	int i;
1076 
1077 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1078 	for (i = 0; i < nr_pages; i++) {
1079 		compat_uptr_t p;
1080 
1081 		if (get_user(p, pages32 + i) ||
1082 			put_user(compat_ptr(p), pages + i))
1083 			return -EFAULT;
1084 	}
1085 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1086 }
1087 
1088 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1089 			compat_ulong_t maxnode,
1090 			const compat_ulong_t __user *old_nodes,
1091 			const compat_ulong_t __user *new_nodes)
1092 {
1093 	unsigned long __user *old = NULL;
1094 	unsigned long __user *new = NULL;
1095 	nodemask_t tmp_mask;
1096 	unsigned long nr_bits;
1097 	unsigned long size;
1098 
1099 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1100 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1101 	if (old_nodes) {
1102 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1103 			return -EFAULT;
1104 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1105 		if (new_nodes)
1106 			new = old + size / sizeof(unsigned long);
1107 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1108 			return -EFAULT;
1109 	}
1110 	if (new_nodes) {
1111 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1112 			return -EFAULT;
1113 		if (new == NULL)
1114 			new = compat_alloc_user_space(size);
1115 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1116 			return -EFAULT;
1117 	}
1118 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1119 }
1120 #endif
1121 
1122 COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1123 		       compat_pid_t, pid,
1124 		       struct compat_timespec __user *, interval)
1125 {
1126 	struct timespec t;
1127 	int ret;
1128 	mm_segment_t old_fs = get_fs();
1129 
1130 	set_fs(KERNEL_DS);
1131 	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1132 	set_fs(old_fs);
1133 	if (put_compat_timespec(&t, interval))
1134 		return -EFAULT;
1135 	return ret;
1136 }
1137 
1138 /*
1139  * Allocate user-space memory for the duration of a single system call,
1140  * in order to marshall parameters inside a compat thunk.
1141  */
1142 void __user *compat_alloc_user_space(unsigned long len)
1143 {
1144 	void __user *ptr;
1145 
1146 	/* If len would occupy more than half of the entire compat space... */
1147 	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1148 		return NULL;
1149 
1150 	ptr = arch_compat_alloc_user_space(len);
1151 
1152 	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1153 		return NULL;
1154 
1155 	return ptr;
1156 }
1157 EXPORT_SYMBOL_GPL(compat_alloc_user_space);
1158