xref: /openbmc/linux/kernel/compat.c (revision 861e10be)
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 asmlinkage long compat_sys_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 asmlinkage long compat_sys_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 asmlinkage long compat_sys_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 asmlinkage long compat_sys_getrusage(int who, struct compat_rusage __user *ru)
520 {
521 	struct rusage r;
522 	int ret;
523 	mm_segment_t old_fs = get_fs();
524 
525 	set_fs(KERNEL_DS);
526 	ret = sys_getrusage(who, (struct rusage __user *) &r);
527 	set_fs(old_fs);
528 
529 	if (ret)
530 		return ret;
531 
532 	if (put_compat_rusage(&r, ru))
533 		return -EFAULT;
534 
535 	return 0;
536 }
537 
538 COMPAT_SYSCALL_DEFINE4(wait4,
539 	compat_pid_t, pid,
540 	compat_uint_t __user *, stat_addr,
541 	int, options,
542 	struct compat_rusage __user *, ru)
543 {
544 	if (!ru) {
545 		return sys_wait4(pid, stat_addr, options, NULL);
546 	} else {
547 		struct rusage r;
548 		int ret;
549 		unsigned int status;
550 		mm_segment_t old_fs = get_fs();
551 
552 		set_fs (KERNEL_DS);
553 		ret = sys_wait4(pid,
554 				(stat_addr ?
555 				 (unsigned int __user *) &status : NULL),
556 				options, (struct rusage __user *) &r);
557 		set_fs (old_fs);
558 
559 		if (ret > 0) {
560 			if (put_compat_rusage(&r, ru))
561 				return -EFAULT;
562 			if (stat_addr && put_user(status, stat_addr))
563 				return -EFAULT;
564 		}
565 		return ret;
566 	}
567 }
568 
569 COMPAT_SYSCALL_DEFINE5(waitid,
570 		int, which, compat_pid_t, pid,
571 		struct compat_siginfo __user *, uinfo, int, options,
572 		struct compat_rusage __user *, uru)
573 {
574 	siginfo_t info;
575 	struct rusage ru;
576 	long ret;
577 	mm_segment_t old_fs = get_fs();
578 
579 	memset(&info, 0, sizeof(info));
580 
581 	set_fs(KERNEL_DS);
582 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
583 			 uru ? (struct rusage __user *)&ru : NULL);
584 	set_fs(old_fs);
585 
586 	if ((ret < 0) || (info.si_signo == 0))
587 		return ret;
588 
589 	if (uru) {
590 		/* sys_waitid() overwrites everything in ru */
591 		if (COMPAT_USE_64BIT_TIME)
592 			ret = copy_to_user(uru, &ru, sizeof(ru));
593 		else
594 			ret = put_compat_rusage(&ru, uru);
595 		if (ret)
596 			return ret;
597 	}
598 
599 	BUG_ON(info.si_code & __SI_MASK);
600 	info.si_code |= __SI_CHLD;
601 	return copy_siginfo_to_user32(uinfo, &info);
602 }
603 
604 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
605 				    unsigned len, struct cpumask *new_mask)
606 {
607 	unsigned long *k;
608 
609 	if (len < cpumask_size())
610 		memset(new_mask, 0, cpumask_size());
611 	else if (len > cpumask_size())
612 		len = cpumask_size();
613 
614 	k = cpumask_bits(new_mask);
615 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
616 }
617 
618 asmlinkage long compat_sys_sched_setaffinity(compat_pid_t pid,
619 					     unsigned int len,
620 					     compat_ulong_t __user *user_mask_ptr)
621 {
622 	cpumask_var_t new_mask;
623 	int retval;
624 
625 	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
626 		return -ENOMEM;
627 
628 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
629 	if (retval)
630 		goto out;
631 
632 	retval = sched_setaffinity(pid, new_mask);
633 out:
634 	free_cpumask_var(new_mask);
635 	return retval;
636 }
637 
638 asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
639 					     compat_ulong_t __user *user_mask_ptr)
640 {
641 	int ret;
642 	cpumask_var_t mask;
643 
644 	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
645 		return -EINVAL;
646 	if (len & (sizeof(compat_ulong_t)-1))
647 		return -EINVAL;
648 
649 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
650 		return -ENOMEM;
651 
652 	ret = sched_getaffinity(pid, mask);
653 	if (ret == 0) {
654 		size_t retlen = min_t(size_t, len, cpumask_size());
655 
656 		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
657 			ret = -EFAULT;
658 		else
659 			ret = retlen;
660 	}
661 	free_cpumask_var(mask);
662 
663 	return ret;
664 }
665 
666 int get_compat_itimerspec(struct itimerspec *dst,
667 			  const struct compat_itimerspec __user *src)
668 {
669 	if (get_compat_timespec(&dst->it_interval, &src->it_interval) ||
670 	    get_compat_timespec(&dst->it_value, &src->it_value))
671 		return -EFAULT;
672 	return 0;
673 }
674 
675 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
676 			  const struct itimerspec *src)
677 {
678 	if (put_compat_timespec(&src->it_interval, &dst->it_interval) ||
679 	    put_compat_timespec(&src->it_value, &dst->it_value))
680 		return -EFAULT;
681 	return 0;
682 }
683 
684 long compat_sys_timer_create(clockid_t which_clock,
685 			struct compat_sigevent __user *timer_event_spec,
686 			timer_t __user *created_timer_id)
687 {
688 	struct sigevent __user *event = NULL;
689 
690 	if (timer_event_spec) {
691 		struct sigevent kevent;
692 
693 		event = compat_alloc_user_space(sizeof(*event));
694 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
695 		    copy_to_user(event, &kevent, sizeof(*event)))
696 			return -EFAULT;
697 	}
698 
699 	return sys_timer_create(which_clock, event, created_timer_id);
700 }
701 
702 long compat_sys_timer_settime(timer_t timer_id, int flags,
703 			  struct compat_itimerspec __user *new,
704 			  struct compat_itimerspec __user *old)
705 {
706 	long err;
707 	mm_segment_t oldfs;
708 	struct itimerspec newts, oldts;
709 
710 	if (!new)
711 		return -EINVAL;
712 	if (get_compat_itimerspec(&newts, new))
713 		return -EFAULT;
714 	oldfs = get_fs();
715 	set_fs(KERNEL_DS);
716 	err = sys_timer_settime(timer_id, flags,
717 				(struct itimerspec __user *) &newts,
718 				(struct itimerspec __user *) &oldts);
719 	set_fs(oldfs);
720 	if (!err && old && put_compat_itimerspec(old, &oldts))
721 		return -EFAULT;
722 	return err;
723 }
724 
725 long compat_sys_timer_gettime(timer_t timer_id,
726 		struct compat_itimerspec __user *setting)
727 {
728 	long err;
729 	mm_segment_t oldfs;
730 	struct itimerspec ts;
731 
732 	oldfs = get_fs();
733 	set_fs(KERNEL_DS);
734 	err = sys_timer_gettime(timer_id,
735 				(struct itimerspec __user *) &ts);
736 	set_fs(oldfs);
737 	if (!err && put_compat_itimerspec(setting, &ts))
738 		return -EFAULT;
739 	return err;
740 }
741 
742 long compat_sys_clock_settime(clockid_t which_clock,
743 		struct compat_timespec __user *tp)
744 {
745 	long err;
746 	mm_segment_t oldfs;
747 	struct timespec ts;
748 
749 	if (get_compat_timespec(&ts, tp))
750 		return -EFAULT;
751 	oldfs = get_fs();
752 	set_fs(KERNEL_DS);
753 	err = sys_clock_settime(which_clock,
754 				(struct timespec __user *) &ts);
755 	set_fs(oldfs);
756 	return err;
757 }
758 
759 long compat_sys_clock_gettime(clockid_t which_clock,
760 		struct compat_timespec __user *tp)
761 {
762 	long err;
763 	mm_segment_t oldfs;
764 	struct timespec ts;
765 
766 	oldfs = get_fs();
767 	set_fs(KERNEL_DS);
768 	err = sys_clock_gettime(which_clock,
769 				(struct timespec __user *) &ts);
770 	set_fs(oldfs);
771 	if (!err && put_compat_timespec(&ts, tp))
772 		return -EFAULT;
773 	return err;
774 }
775 
776 long compat_sys_clock_adjtime(clockid_t which_clock,
777 		struct compat_timex __user *utp)
778 {
779 	struct timex txc;
780 	mm_segment_t oldfs;
781 	int err, ret;
782 
783 	err = compat_get_timex(&txc, utp);
784 	if (err)
785 		return err;
786 
787 	oldfs = get_fs();
788 	set_fs(KERNEL_DS);
789 	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
790 	set_fs(oldfs);
791 
792 	err = compat_put_timex(utp, &txc);
793 	if (err)
794 		return err;
795 
796 	return ret;
797 }
798 
799 long compat_sys_clock_getres(clockid_t which_clock,
800 		struct compat_timespec __user *tp)
801 {
802 	long err;
803 	mm_segment_t oldfs;
804 	struct timespec ts;
805 
806 	oldfs = get_fs();
807 	set_fs(KERNEL_DS);
808 	err = sys_clock_getres(which_clock,
809 			       (struct timespec __user *) &ts);
810 	set_fs(oldfs);
811 	if (!err && tp && put_compat_timespec(&ts, tp))
812 		return -EFAULT;
813 	return err;
814 }
815 
816 static long compat_clock_nanosleep_restart(struct restart_block *restart)
817 {
818 	long err;
819 	mm_segment_t oldfs;
820 	struct timespec tu;
821 	struct compat_timespec *rmtp = restart->nanosleep.compat_rmtp;
822 
823 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
824 	oldfs = get_fs();
825 	set_fs(KERNEL_DS);
826 	err = clock_nanosleep_restart(restart);
827 	set_fs(oldfs);
828 
829 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
830 	    put_compat_timespec(&tu, rmtp))
831 		return -EFAULT;
832 
833 	if (err == -ERESTART_RESTARTBLOCK) {
834 		restart->fn = compat_clock_nanosleep_restart;
835 		restart->nanosleep.compat_rmtp = rmtp;
836 	}
837 	return err;
838 }
839 
840 long compat_sys_clock_nanosleep(clockid_t which_clock, int flags,
841 			    struct compat_timespec __user *rqtp,
842 			    struct compat_timespec __user *rmtp)
843 {
844 	long err;
845 	mm_segment_t oldfs;
846 	struct timespec in, out;
847 	struct restart_block *restart;
848 
849 	if (get_compat_timespec(&in, rqtp))
850 		return -EFAULT;
851 
852 	oldfs = get_fs();
853 	set_fs(KERNEL_DS);
854 	err = sys_clock_nanosleep(which_clock, flags,
855 				  (struct timespec __user *) &in,
856 				  (struct timespec __user *) &out);
857 	set_fs(oldfs);
858 
859 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
860 	    put_compat_timespec(&out, rmtp))
861 		return -EFAULT;
862 
863 	if (err == -ERESTART_RESTARTBLOCK) {
864 		restart = &current_thread_info()->restart_block;
865 		restart->fn = compat_clock_nanosleep_restart;
866 		restart->nanosleep.compat_rmtp = rmtp;
867 	}
868 	return err;
869 }
870 
871 /*
872  * We currently only need the following fields from the sigevent
873  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
874  * sigev_notify_thread_id).  The others are handled in user mode.
875  * We also assume that copying sigev_value.sival_int is sufficient
876  * to keep all the bits of sigev_value.sival_ptr intact.
877  */
878 int get_compat_sigevent(struct sigevent *event,
879 		const struct compat_sigevent __user *u_event)
880 {
881 	memset(event, 0, sizeof(*event));
882 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
883 		__get_user(event->sigev_value.sival_int,
884 			&u_event->sigev_value.sival_int) ||
885 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
886 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
887 		__get_user(event->sigev_notify_thread_id,
888 			&u_event->sigev_notify_thread_id))
889 		? -EFAULT : 0;
890 }
891 
892 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
893 		       unsigned long bitmap_size)
894 {
895 	int i, j;
896 	unsigned long m;
897 	compat_ulong_t um;
898 	unsigned long nr_compat_longs;
899 
900 	/* align bitmap up to nearest compat_long_t boundary */
901 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
902 
903 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
904 		return -EFAULT;
905 
906 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
907 
908 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
909 		m = 0;
910 
911 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
912 			/*
913 			 * We dont want to read past the end of the userspace
914 			 * bitmap. We must however ensure the end of the
915 			 * kernel bitmap is zeroed.
916 			 */
917 			if (nr_compat_longs-- > 0) {
918 				if (__get_user(um, umask))
919 					return -EFAULT;
920 			} else {
921 				um = 0;
922 			}
923 
924 			umask++;
925 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
926 		}
927 		*mask++ = m;
928 	}
929 
930 	return 0;
931 }
932 
933 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
934 		       unsigned long bitmap_size)
935 {
936 	int i, j;
937 	unsigned long m;
938 	compat_ulong_t um;
939 	unsigned long nr_compat_longs;
940 
941 	/* align bitmap up to nearest compat_long_t boundary */
942 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
943 
944 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
945 		return -EFAULT;
946 
947 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
948 
949 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
950 		m = *mask++;
951 
952 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
953 			um = m;
954 
955 			/*
956 			 * We dont want to write past the end of the userspace
957 			 * bitmap.
958 			 */
959 			if (nr_compat_longs-- > 0) {
960 				if (__put_user(um, umask))
961 					return -EFAULT;
962 			}
963 
964 			umask++;
965 			m >>= 4*sizeof(um);
966 			m >>= 4*sizeof(um);
967 		}
968 	}
969 
970 	return 0;
971 }
972 
973 void
974 sigset_from_compat (sigset_t *set, compat_sigset_t *compat)
975 {
976 	switch (_NSIG_WORDS) {
977 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
978 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
979 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
980 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
981 	}
982 }
983 EXPORT_SYMBOL_GPL(sigset_from_compat);
984 
985 asmlinkage long
986 compat_sys_rt_sigtimedwait (compat_sigset_t __user *uthese,
987 		struct compat_siginfo __user *uinfo,
988 		struct compat_timespec __user *uts, compat_size_t sigsetsize)
989 {
990 	compat_sigset_t s32;
991 	sigset_t s;
992 	struct timespec t;
993 	siginfo_t info;
994 	long ret;
995 
996 	if (sigsetsize != sizeof(sigset_t))
997 		return -EINVAL;
998 
999 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
1000 		return -EFAULT;
1001 	sigset_from_compat(&s, &s32);
1002 
1003 	if (uts) {
1004 		if (compat_get_timespec(&t, uts))
1005 			return -EFAULT;
1006 	}
1007 
1008 	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1009 
1010 	if (ret > 0 && uinfo) {
1011 		if (copy_siginfo_to_user32(uinfo, &info))
1012 			ret = -EFAULT;
1013 	}
1014 
1015 	return ret;
1016 
1017 }
1018 
1019 asmlinkage long
1020 compat_sys_rt_tgsigqueueinfo(compat_pid_t tgid, compat_pid_t pid, int sig,
1021 			     struct compat_siginfo __user *uinfo)
1022 {
1023 	siginfo_t info;
1024 
1025 	if (copy_siginfo_from_user32(&info, uinfo))
1026 		return -EFAULT;
1027 	return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
1028 }
1029 
1030 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1031 
1032 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1033 
1034 asmlinkage long compat_sys_time(compat_time_t __user * tloc)
1035 {
1036 	compat_time_t i;
1037 	struct timeval tv;
1038 
1039 	do_gettimeofday(&tv);
1040 	i = tv.tv_sec;
1041 
1042 	if (tloc) {
1043 		if (put_user(i,tloc))
1044 			return -EFAULT;
1045 	}
1046 	force_successful_syscall_return();
1047 	return i;
1048 }
1049 
1050 asmlinkage long compat_sys_stime(compat_time_t __user *tptr)
1051 {
1052 	struct timespec tv;
1053 	int err;
1054 
1055 	if (get_user(tv.tv_sec, tptr))
1056 		return -EFAULT;
1057 
1058 	tv.tv_nsec = 0;
1059 
1060 	err = security_settime(&tv, NULL);
1061 	if (err)
1062 		return err;
1063 
1064 	do_settimeofday(&tv);
1065 	return 0;
1066 }
1067 
1068 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1069 
1070 #ifdef __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND
1071 asmlinkage long compat_sys_rt_sigsuspend(compat_sigset_t __user *unewset, compat_size_t sigsetsize)
1072 {
1073 	sigset_t newset;
1074 	compat_sigset_t newset32;
1075 
1076 	/* XXX: Don't preclude handling different sized sigset_t's.  */
1077 	if (sigsetsize != sizeof(sigset_t))
1078 		return -EINVAL;
1079 
1080 	if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
1081 		return -EFAULT;
1082 	sigset_from_compat(&newset, &newset32);
1083 	return sigsuspend(&newset);
1084 }
1085 #endif /* __ARCH_WANT_COMPAT_SYS_RT_SIGSUSPEND */
1086 
1087 asmlinkage long compat_sys_adjtimex(struct compat_timex __user *utp)
1088 {
1089 	struct timex txc;
1090 	int err, ret;
1091 
1092 	err = compat_get_timex(&txc, utp);
1093 	if (err)
1094 		return err;
1095 
1096 	ret = do_adjtimex(&txc);
1097 
1098 	err = compat_put_timex(utp, &txc);
1099 	if (err)
1100 		return err;
1101 
1102 	return ret;
1103 }
1104 
1105 #ifdef CONFIG_NUMA
1106 asmlinkage long compat_sys_move_pages(pid_t pid, unsigned long nr_pages,
1107 		compat_uptr_t __user *pages32,
1108 		const int __user *nodes,
1109 		int __user *status,
1110 		int flags)
1111 {
1112 	const void __user * __user *pages;
1113 	int i;
1114 
1115 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1116 	for (i = 0; i < nr_pages; i++) {
1117 		compat_uptr_t p;
1118 
1119 		if (get_user(p, pages32 + i) ||
1120 			put_user(compat_ptr(p), pages + i))
1121 			return -EFAULT;
1122 	}
1123 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1124 }
1125 
1126 asmlinkage long compat_sys_migrate_pages(compat_pid_t pid,
1127 			compat_ulong_t maxnode,
1128 			const compat_ulong_t __user *old_nodes,
1129 			const compat_ulong_t __user *new_nodes)
1130 {
1131 	unsigned long __user *old = NULL;
1132 	unsigned long __user *new = NULL;
1133 	nodemask_t tmp_mask;
1134 	unsigned long nr_bits;
1135 	unsigned long size;
1136 
1137 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1138 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1139 	if (old_nodes) {
1140 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1141 			return -EFAULT;
1142 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1143 		if (new_nodes)
1144 			new = old + size / sizeof(unsigned long);
1145 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1146 			return -EFAULT;
1147 	}
1148 	if (new_nodes) {
1149 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1150 			return -EFAULT;
1151 		if (new == NULL)
1152 			new = compat_alloc_user_space(size);
1153 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1154 			return -EFAULT;
1155 	}
1156 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1157 }
1158 #endif
1159 
1160 struct compat_sysinfo {
1161 	s32 uptime;
1162 	u32 loads[3];
1163 	u32 totalram;
1164 	u32 freeram;
1165 	u32 sharedram;
1166 	u32 bufferram;
1167 	u32 totalswap;
1168 	u32 freeswap;
1169 	u16 procs;
1170 	u16 pad;
1171 	u32 totalhigh;
1172 	u32 freehigh;
1173 	u32 mem_unit;
1174 	char _f[20-2*sizeof(u32)-sizeof(int)];
1175 };
1176 
1177 asmlinkage long
1178 compat_sys_sysinfo(struct compat_sysinfo __user *info)
1179 {
1180 	struct sysinfo s;
1181 
1182 	do_sysinfo(&s);
1183 
1184 	/* Check to see if any memory value is too large for 32-bit and scale
1185 	 *  down if needed
1186 	 */
1187 	if ((s.totalram >> 32) || (s.totalswap >> 32)) {
1188 		int bitcount = 0;
1189 
1190 		while (s.mem_unit < PAGE_SIZE) {
1191 			s.mem_unit <<= 1;
1192 			bitcount++;
1193 		}
1194 
1195 		s.totalram >>= bitcount;
1196 		s.freeram >>= bitcount;
1197 		s.sharedram >>= bitcount;
1198 		s.bufferram >>= bitcount;
1199 		s.totalswap >>= bitcount;
1200 		s.freeswap >>= bitcount;
1201 		s.totalhigh >>= bitcount;
1202 		s.freehigh >>= bitcount;
1203 	}
1204 
1205 	if (!access_ok(VERIFY_WRITE, info, sizeof(struct compat_sysinfo)) ||
1206 	    __put_user (s.uptime, &info->uptime) ||
1207 	    __put_user (s.loads[0], &info->loads[0]) ||
1208 	    __put_user (s.loads[1], &info->loads[1]) ||
1209 	    __put_user (s.loads[2], &info->loads[2]) ||
1210 	    __put_user (s.totalram, &info->totalram) ||
1211 	    __put_user (s.freeram, &info->freeram) ||
1212 	    __put_user (s.sharedram, &info->sharedram) ||
1213 	    __put_user (s.bufferram, &info->bufferram) ||
1214 	    __put_user (s.totalswap, &info->totalswap) ||
1215 	    __put_user (s.freeswap, &info->freeswap) ||
1216 	    __put_user (s.procs, &info->procs) ||
1217 	    __put_user (s.totalhigh, &info->totalhigh) ||
1218 	    __put_user (s.freehigh, &info->freehigh) ||
1219 	    __put_user (s.mem_unit, &info->mem_unit))
1220 		return -EFAULT;
1221 
1222 	return 0;
1223 }
1224 
1225 #ifdef __ARCH_WANT_COMPAT_SYS_SCHED_RR_GET_INTERVAL
1226 asmlinkage long compat_sys_sched_rr_get_interval(compat_pid_t pid,
1227 						 struct compat_timespec __user *interval)
1228 {
1229 	struct timespec t;
1230 	int ret;
1231 	mm_segment_t old_fs = get_fs();
1232 
1233 	set_fs(KERNEL_DS);
1234 	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1235 	set_fs(old_fs);
1236 	if (put_compat_timespec(&t, interval))
1237 		return -EFAULT;
1238 	return ret;
1239 }
1240 #endif /* __ARCH_WANT_COMPAT_SYS_SCHED_RR_GET_INTERVAL */
1241 
1242 /*
1243  * Allocate user-space memory for the duration of a single system call,
1244  * in order to marshall parameters inside a compat thunk.
1245  */
1246 void __user *compat_alloc_user_space(unsigned long len)
1247 {
1248 	void __user *ptr;
1249 
1250 	/* If len would occupy more than half of the entire compat space... */
1251 	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1252 		return NULL;
1253 
1254 	ptr = arch_compat_alloc_user_space(len);
1255 
1256 	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1257 		return NULL;
1258 
1259 	return ptr;
1260 }
1261 EXPORT_SYMBOL_GPL(compat_alloc_user_space);
1262