xref: /linux/kernel/compat.c (revision 9e9f60108423f18a99c9cc93ef7f23490ecc709b)
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 static int compat_get_timex(struct timex *txc, struct compat_timex __user *utp)
34 {
35 	memset(txc, 0, sizeof(struct timex));
36 
37 	if (!access_ok(VERIFY_READ, utp, sizeof(struct compat_timex)) ||
38 			__get_user(txc->modes, &utp->modes) ||
39 			__get_user(txc->offset, &utp->offset) ||
40 			__get_user(txc->freq, &utp->freq) ||
41 			__get_user(txc->maxerror, &utp->maxerror) ||
42 			__get_user(txc->esterror, &utp->esterror) ||
43 			__get_user(txc->status, &utp->status) ||
44 			__get_user(txc->constant, &utp->constant) ||
45 			__get_user(txc->precision, &utp->precision) ||
46 			__get_user(txc->tolerance, &utp->tolerance) ||
47 			__get_user(txc->time.tv_sec, &utp->time.tv_sec) ||
48 			__get_user(txc->time.tv_usec, &utp->time.tv_usec) ||
49 			__get_user(txc->tick, &utp->tick) ||
50 			__get_user(txc->ppsfreq, &utp->ppsfreq) ||
51 			__get_user(txc->jitter, &utp->jitter) ||
52 			__get_user(txc->shift, &utp->shift) ||
53 			__get_user(txc->stabil, &utp->stabil) ||
54 			__get_user(txc->jitcnt, &utp->jitcnt) ||
55 			__get_user(txc->calcnt, &utp->calcnt) ||
56 			__get_user(txc->errcnt, &utp->errcnt) ||
57 			__get_user(txc->stbcnt, &utp->stbcnt))
58 		return -EFAULT;
59 
60 	return 0;
61 }
62 
63 static int compat_put_timex(struct compat_timex __user *utp, struct timex *txc)
64 {
65 	if (!access_ok(VERIFY_WRITE, utp, sizeof(struct compat_timex)) ||
66 			__put_user(txc->modes, &utp->modes) ||
67 			__put_user(txc->offset, &utp->offset) ||
68 			__put_user(txc->freq, &utp->freq) ||
69 			__put_user(txc->maxerror, &utp->maxerror) ||
70 			__put_user(txc->esterror, &utp->esterror) ||
71 			__put_user(txc->status, &utp->status) ||
72 			__put_user(txc->constant, &utp->constant) ||
73 			__put_user(txc->precision, &utp->precision) ||
74 			__put_user(txc->tolerance, &utp->tolerance) ||
75 			__put_user(txc->time.tv_sec, &utp->time.tv_sec) ||
76 			__put_user(txc->time.tv_usec, &utp->time.tv_usec) ||
77 			__put_user(txc->tick, &utp->tick) ||
78 			__put_user(txc->ppsfreq, &utp->ppsfreq) ||
79 			__put_user(txc->jitter, &utp->jitter) ||
80 			__put_user(txc->shift, &utp->shift) ||
81 			__put_user(txc->stabil, &utp->stabil) ||
82 			__put_user(txc->jitcnt, &utp->jitcnt) ||
83 			__put_user(txc->calcnt, &utp->calcnt) ||
84 			__put_user(txc->errcnt, &utp->errcnt) ||
85 			__put_user(txc->stbcnt, &utp->stbcnt) ||
86 			__put_user(txc->tai, &utp->tai))
87 		return -EFAULT;
88 	return 0;
89 }
90 
91 COMPAT_SYSCALL_DEFINE2(gettimeofday, struct compat_timeval __user *, tv,
92 		       struct timezone __user *, tz)
93 {
94 	if (tv) {
95 		struct timeval ktv;
96 		do_gettimeofday(&ktv);
97 		if (compat_put_timeval(&ktv, tv))
98 			return -EFAULT;
99 	}
100 	if (tz) {
101 		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
102 			return -EFAULT;
103 	}
104 
105 	return 0;
106 }
107 
108 COMPAT_SYSCALL_DEFINE2(settimeofday, struct compat_timeval __user *, tv,
109 		       struct timezone __user *, tz)
110 {
111 	struct timeval user_tv;
112 	struct timespec	new_ts;
113 	struct timezone new_tz;
114 
115 	if (tv) {
116 		if (compat_get_timeval(&user_tv, tv))
117 			return -EFAULT;
118 		new_ts.tv_sec = user_tv.tv_sec;
119 		new_ts.tv_nsec = user_tv.tv_usec * NSEC_PER_USEC;
120 	}
121 	if (tz) {
122 		if (copy_from_user(&new_tz, tz, sizeof(*tz)))
123 			return -EFAULT;
124 	}
125 
126 	return do_sys_settimeofday(tv ? &new_ts : NULL, tz ? &new_tz : NULL);
127 }
128 
129 static int __compat_get_timeval(struct timeval *tv, const struct compat_timeval __user *ctv)
130 {
131 	return (!access_ok(VERIFY_READ, ctv, sizeof(*ctv)) ||
132 			__get_user(tv->tv_sec, &ctv->tv_sec) ||
133 			__get_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
134 }
135 
136 static int __compat_put_timeval(const struct timeval *tv, struct compat_timeval __user *ctv)
137 {
138 	return (!access_ok(VERIFY_WRITE, ctv, sizeof(*ctv)) ||
139 			__put_user(tv->tv_sec, &ctv->tv_sec) ||
140 			__put_user(tv->tv_usec, &ctv->tv_usec)) ? -EFAULT : 0;
141 }
142 
143 static int __compat_get_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
144 {
145 	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
146 			__get_user(ts->tv_sec, &cts->tv_sec) ||
147 			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
148 }
149 
150 static int __compat_put_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
151 {
152 	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
153 			__put_user(ts->tv_sec, &cts->tv_sec) ||
154 			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
155 }
156 
157 int compat_get_timeval(struct timeval *tv, const void __user *utv)
158 {
159 	if (COMPAT_USE_64BIT_TIME)
160 		return copy_from_user(tv, utv, sizeof(*tv)) ? -EFAULT : 0;
161 	else
162 		return __compat_get_timeval(tv, utv);
163 }
164 EXPORT_SYMBOL_GPL(compat_get_timeval);
165 
166 int compat_put_timeval(const struct timeval *tv, void __user *utv)
167 {
168 	if (COMPAT_USE_64BIT_TIME)
169 		return copy_to_user(utv, tv, sizeof(*tv)) ? -EFAULT : 0;
170 	else
171 		return __compat_put_timeval(tv, utv);
172 }
173 EXPORT_SYMBOL_GPL(compat_put_timeval);
174 
175 int compat_get_timespec(struct timespec *ts, const void __user *uts)
176 {
177 	if (COMPAT_USE_64BIT_TIME)
178 		return copy_from_user(ts, uts, sizeof(*ts)) ? -EFAULT : 0;
179 	else
180 		return __compat_get_timespec(ts, uts);
181 }
182 EXPORT_SYMBOL_GPL(compat_get_timespec);
183 
184 int compat_put_timespec(const struct timespec *ts, void __user *uts)
185 {
186 	if (COMPAT_USE_64BIT_TIME)
187 		return copy_to_user(uts, ts, sizeof(*ts)) ? -EFAULT : 0;
188 	else
189 		return __compat_put_timespec(ts, uts);
190 }
191 EXPORT_SYMBOL_GPL(compat_put_timespec);
192 
193 int compat_convert_timespec(struct timespec __user **kts,
194 			    const void __user *cts)
195 {
196 	struct timespec ts;
197 	struct timespec __user *uts;
198 
199 	if (!cts || COMPAT_USE_64BIT_TIME) {
200 		*kts = (struct timespec __user *)cts;
201 		return 0;
202 	}
203 
204 	uts = compat_alloc_user_space(sizeof(ts));
205 	if (!uts)
206 		return -EFAULT;
207 	if (compat_get_timespec(&ts, cts))
208 		return -EFAULT;
209 	if (copy_to_user(uts, &ts, sizeof(ts)))
210 		return -EFAULT;
211 
212 	*kts = uts;
213 	return 0;
214 }
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 == -ERESTART_RESTARTBLOCK) {
230 		rmtp = restart->nanosleep.compat_rmtp;
231 
232 		if (rmtp && compat_put_timespec(&rmt, rmtp))
233 			return -EFAULT;
234 	}
235 
236 	return ret;
237 }
238 
239 COMPAT_SYSCALL_DEFINE2(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 (compat_get_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 	/*
260 	 * hrtimer_nanosleep() can only return 0 or
261 	 * -ERESTART_RESTARTBLOCK here because:
262 	 *
263 	 * - we call it with HRTIMER_MODE_REL and therefor exclude the
264 	 *   -ERESTARTNOHAND return path.
265 	 *
266 	 * - we supply the rmtp argument from the task stack (due to
267 	 *   the necessary compat conversion. So the update cannot
268 	 *   fail, which excludes the -EFAULT return path as well. If
269 	 *   it fails nevertheless we have a bigger problem and wont
270 	 *   reach this place anymore.
271 	 *
272 	 * - if the return value is 0, we do not have to update rmtp
273 	 *    because there is no remaining time.
274 	 *
275 	 * We check for -ERESTART_RESTARTBLOCK nevertheless if the
276 	 * core implementation decides to return random nonsense.
277 	 */
278 	if (ret == -ERESTART_RESTARTBLOCK) {
279 		struct restart_block *restart
280 			= &current_thread_info()->restart_block;
281 
282 		restart->fn = compat_nanosleep_restart;
283 		restart->nanosleep.compat_rmtp = rmtp;
284 
285 		if (rmtp && compat_put_timespec(&rmt, rmtp))
286 			return -EFAULT;
287 	}
288 	return ret;
289 }
290 
291 static inline long get_compat_itimerval(struct itimerval *o,
292 		struct compat_itimerval __user *i)
293 {
294 	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
295 		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
296 		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
297 		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
298 		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
299 }
300 
301 static inline long put_compat_itimerval(struct compat_itimerval __user *o,
302 		struct itimerval *i)
303 {
304 	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
305 		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
306 		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
307 		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
308 		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
309 }
310 
311 COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
312 		struct compat_itimerval __user *, it)
313 {
314 	struct itimerval kit;
315 	int error;
316 
317 	error = do_getitimer(which, &kit);
318 	if (!error && put_compat_itimerval(it, &kit))
319 		error = -EFAULT;
320 	return error;
321 }
322 
323 COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
324 		struct compat_itimerval __user *, in,
325 		struct compat_itimerval __user *, out)
326 {
327 	struct itimerval kin, kout;
328 	int error;
329 
330 	if (in) {
331 		if (get_compat_itimerval(&kin, in))
332 			return -EFAULT;
333 	} else
334 		memset(&kin, 0, sizeof(kin));
335 
336 	error = do_setitimer(which, &kin, out ? &kout : NULL);
337 	if (error || !out)
338 		return error;
339 	if (put_compat_itimerval(out, &kout))
340 		return -EFAULT;
341 	return 0;
342 }
343 
344 static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
345 {
346 	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
347 }
348 
349 COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
350 {
351 	if (tbuf) {
352 		struct tms tms;
353 		struct compat_tms tmp;
354 
355 		do_sys_times(&tms);
356 		/* Convert our struct tms to the compat version. */
357 		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
358 		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
359 		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
360 		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
361 		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
362 			return -EFAULT;
363 	}
364 	force_successful_syscall_return();
365 	return compat_jiffies_to_clock_t(jiffies);
366 }
367 
368 #ifdef __ARCH_WANT_SYS_SIGPENDING
369 
370 /*
371  * Assumption: old_sigset_t and compat_old_sigset_t are both
372  * types that can be passed to put_user()/get_user().
373  */
374 
375 COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
376 {
377 	old_sigset_t s;
378 	long ret;
379 	mm_segment_t old_fs = get_fs();
380 
381 	set_fs(KERNEL_DS);
382 	ret = sys_sigpending((old_sigset_t __user *) &s);
383 	set_fs(old_fs);
384 	if (ret == 0)
385 		ret = put_user(s, set);
386 	return ret;
387 }
388 
389 #endif
390 
391 #ifdef __ARCH_WANT_SYS_SIGPROCMASK
392 
393 /*
394  * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
395  * blocked set of signals to the supplied signal set
396  */
397 static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
398 {
399 	memcpy(blocked->sig, &set, sizeof(set));
400 }
401 
402 COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
403 		       compat_old_sigset_t __user *, nset,
404 		       compat_old_sigset_t __user *, oset)
405 {
406 	old_sigset_t old_set, new_set;
407 	sigset_t new_blocked;
408 
409 	old_set = current->blocked.sig[0];
410 
411 	if (nset) {
412 		if (get_user(new_set, nset))
413 			return -EFAULT;
414 		new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
415 
416 		new_blocked = current->blocked;
417 
418 		switch (how) {
419 		case SIG_BLOCK:
420 			sigaddsetmask(&new_blocked, new_set);
421 			break;
422 		case SIG_UNBLOCK:
423 			sigdelsetmask(&new_blocked, new_set);
424 			break;
425 		case SIG_SETMASK:
426 			compat_sig_setmask(&new_blocked, new_set);
427 			break;
428 		default:
429 			return -EINVAL;
430 		}
431 
432 		set_current_blocked(&new_blocked);
433 	}
434 
435 	if (oset) {
436 		if (put_user(old_set, oset))
437 			return -EFAULT;
438 	}
439 
440 	return 0;
441 }
442 
443 #endif
444 
445 COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
446 		       struct compat_rlimit __user *, rlim)
447 {
448 	struct rlimit r;
449 
450 	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
451 	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
452 	    __get_user(r.rlim_max, &rlim->rlim_max))
453 		return -EFAULT;
454 
455 	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
456 		r.rlim_cur = RLIM_INFINITY;
457 	if (r.rlim_max == COMPAT_RLIM_INFINITY)
458 		r.rlim_max = RLIM_INFINITY;
459 	return do_prlimit(current, resource, &r, NULL);
460 }
461 
462 #ifdef COMPAT_RLIM_OLD_INFINITY
463 
464 COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
465 		       struct compat_rlimit __user *, rlim)
466 {
467 	struct rlimit r;
468 	int ret;
469 	mm_segment_t old_fs = get_fs();
470 
471 	set_fs(KERNEL_DS);
472 	ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r);
473 	set_fs(old_fs);
474 
475 	if (!ret) {
476 		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
477 			r.rlim_cur = COMPAT_RLIM_INFINITY;
478 		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
479 			r.rlim_max = COMPAT_RLIM_INFINITY;
480 
481 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
482 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
483 		    __put_user(r.rlim_max, &rlim->rlim_max))
484 			return -EFAULT;
485 	}
486 	return ret;
487 }
488 
489 #endif
490 
491 COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
492 		       struct compat_rlimit __user *, rlim)
493 {
494 	struct rlimit r;
495 	int ret;
496 
497 	ret = do_prlimit(current, resource, NULL, &r);
498 	if (!ret) {
499 		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
500 			r.rlim_cur = COMPAT_RLIM_INFINITY;
501 		if (r.rlim_max > COMPAT_RLIM_INFINITY)
502 			r.rlim_max = COMPAT_RLIM_INFINITY;
503 
504 		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
505 		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
506 		    __put_user(r.rlim_max, &rlim->rlim_max))
507 			return -EFAULT;
508 	}
509 	return ret;
510 }
511 
512 int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
513 {
514 	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
515 	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
516 	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
517 	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
518 	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
519 	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
520 	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
521 	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
522 	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
523 	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
524 	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
525 	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
526 	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
527 	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
528 	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
529 	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
530 	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
531 	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
532 	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
533 		return -EFAULT;
534 	return 0;
535 }
536 
537 COMPAT_SYSCALL_DEFINE4(wait4,
538 	compat_pid_t, pid,
539 	compat_uint_t __user *, stat_addr,
540 	int, options,
541 	struct compat_rusage __user *, ru)
542 {
543 	if (!ru) {
544 		return sys_wait4(pid, stat_addr, options, NULL);
545 	} else {
546 		struct rusage r;
547 		int ret;
548 		unsigned int status;
549 		mm_segment_t old_fs = get_fs();
550 
551 		set_fs (KERNEL_DS);
552 		ret = sys_wait4(pid,
553 				(stat_addr ?
554 				 (unsigned int __user *) &status : NULL),
555 				options, (struct rusage __user *) &r);
556 		set_fs (old_fs);
557 
558 		if (ret > 0) {
559 			if (put_compat_rusage(&r, ru))
560 				return -EFAULT;
561 			if (stat_addr && put_user(status, stat_addr))
562 				return -EFAULT;
563 		}
564 		return ret;
565 	}
566 }
567 
568 COMPAT_SYSCALL_DEFINE5(waitid,
569 		int, which, compat_pid_t, pid,
570 		struct compat_siginfo __user *, uinfo, int, options,
571 		struct compat_rusage __user *, uru)
572 {
573 	siginfo_t info;
574 	struct rusage ru;
575 	long ret;
576 	mm_segment_t old_fs = get_fs();
577 
578 	memset(&info, 0, sizeof(info));
579 
580 	set_fs(KERNEL_DS);
581 	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
582 			 uru ? (struct rusage __user *)&ru : NULL);
583 	set_fs(old_fs);
584 
585 	if ((ret < 0) || (info.si_signo == 0))
586 		return ret;
587 
588 	if (uru) {
589 		/* sys_waitid() overwrites everything in ru */
590 		if (COMPAT_USE_64BIT_TIME)
591 			ret = copy_to_user(uru, &ru, sizeof(ru));
592 		else
593 			ret = put_compat_rusage(&ru, uru);
594 		if (ret)
595 			return -EFAULT;
596 	}
597 
598 	BUG_ON(info.si_code & __SI_MASK);
599 	info.si_code |= __SI_CHLD;
600 	return copy_siginfo_to_user32(uinfo, &info);
601 }
602 
603 static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
604 				    unsigned len, struct cpumask *new_mask)
605 {
606 	unsigned long *k;
607 
608 	if (len < cpumask_size())
609 		memset(new_mask, 0, cpumask_size());
610 	else if (len > cpumask_size())
611 		len = cpumask_size();
612 
613 	k = cpumask_bits(new_mask);
614 	return compat_get_bitmap(k, user_mask_ptr, len * 8);
615 }
616 
617 COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid,
618 		       unsigned int, len,
619 		       compat_ulong_t __user *, user_mask_ptr)
620 {
621 	cpumask_var_t new_mask;
622 	int retval;
623 
624 	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
625 		return -ENOMEM;
626 
627 	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
628 	if (retval)
629 		goto out;
630 
631 	retval = sched_setaffinity(pid, new_mask);
632 out:
633 	free_cpumask_var(new_mask);
634 	return retval;
635 }
636 
637 COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t,  pid, unsigned int, len,
638 		       compat_ulong_t __user *, user_mask_ptr)
639 {
640 	int ret;
641 	cpumask_var_t mask;
642 
643 	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
644 		return -EINVAL;
645 	if (len & (sizeof(compat_ulong_t)-1))
646 		return -EINVAL;
647 
648 	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
649 		return -ENOMEM;
650 
651 	ret = sched_getaffinity(pid, mask);
652 	if (ret == 0) {
653 		size_t retlen = min_t(size_t, len, cpumask_size());
654 
655 		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
656 			ret = -EFAULT;
657 		else
658 			ret = retlen;
659 	}
660 	free_cpumask_var(mask);
661 
662 	return ret;
663 }
664 
665 int get_compat_itimerspec(struct itimerspec *dst,
666 			  const struct compat_itimerspec __user *src)
667 {
668 	if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
669 	    __compat_get_timespec(&dst->it_value, &src->it_value))
670 		return -EFAULT;
671 	return 0;
672 }
673 
674 int put_compat_itimerspec(struct compat_itimerspec __user *dst,
675 			  const struct itimerspec *src)
676 {
677 	if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
678 	    __compat_put_timespec(&src->it_value, &dst->it_value))
679 		return -EFAULT;
680 	return 0;
681 }
682 
683 COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
684 		       struct compat_sigevent __user *, timer_event_spec,
685 		       timer_t __user *, created_timer_id)
686 {
687 	struct sigevent __user *event = NULL;
688 
689 	if (timer_event_spec) {
690 		struct sigevent kevent;
691 
692 		event = compat_alloc_user_space(sizeof(*event));
693 		if (get_compat_sigevent(&kevent, timer_event_spec) ||
694 		    copy_to_user(event, &kevent, sizeof(*event)))
695 			return -EFAULT;
696 	}
697 
698 	return sys_timer_create(which_clock, event, created_timer_id);
699 }
700 
701 COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
702 		       struct compat_itimerspec __user *, new,
703 		       struct compat_itimerspec __user *, old)
704 {
705 	long err;
706 	mm_segment_t oldfs;
707 	struct itimerspec newts, oldts;
708 
709 	if (!new)
710 		return -EINVAL;
711 	if (get_compat_itimerspec(&newts, new))
712 		return -EFAULT;
713 	oldfs = get_fs();
714 	set_fs(KERNEL_DS);
715 	err = sys_timer_settime(timer_id, flags,
716 				(struct itimerspec __user *) &newts,
717 				(struct itimerspec __user *) &oldts);
718 	set_fs(oldfs);
719 	if (!err && old && put_compat_itimerspec(old, &oldts))
720 		return -EFAULT;
721 	return err;
722 }
723 
724 COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
725 		       struct compat_itimerspec __user *, setting)
726 {
727 	long err;
728 	mm_segment_t oldfs;
729 	struct itimerspec ts;
730 
731 	oldfs = get_fs();
732 	set_fs(KERNEL_DS);
733 	err = sys_timer_gettime(timer_id,
734 				(struct itimerspec __user *) &ts);
735 	set_fs(oldfs);
736 	if (!err && put_compat_itimerspec(setting, &ts))
737 		return -EFAULT;
738 	return err;
739 }
740 
741 COMPAT_SYSCALL_DEFINE2(clock_settime, clockid_t, which_clock,
742 		       struct compat_timespec __user *, tp)
743 {
744 	long err;
745 	mm_segment_t oldfs;
746 	struct timespec ts;
747 
748 	if (compat_get_timespec(&ts, tp))
749 		return -EFAULT;
750 	oldfs = get_fs();
751 	set_fs(KERNEL_DS);
752 	err = sys_clock_settime(which_clock,
753 				(struct timespec __user *) &ts);
754 	set_fs(oldfs);
755 	return err;
756 }
757 
758 COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
759 		       struct compat_timespec __user *, tp)
760 {
761 	long err;
762 	mm_segment_t oldfs;
763 	struct timespec ts;
764 
765 	oldfs = get_fs();
766 	set_fs(KERNEL_DS);
767 	err = sys_clock_gettime(which_clock,
768 				(struct timespec __user *) &ts);
769 	set_fs(oldfs);
770 	if (!err && compat_put_timespec(&ts, tp))
771 		return -EFAULT;
772 	return err;
773 }
774 
775 COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
776 		       struct compat_timex __user *, utp)
777 {
778 	struct timex txc;
779 	mm_segment_t oldfs;
780 	int err, ret;
781 
782 	err = compat_get_timex(&txc, utp);
783 	if (err)
784 		return err;
785 
786 	oldfs = get_fs();
787 	set_fs(KERNEL_DS);
788 	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
789 	set_fs(oldfs);
790 
791 	err = compat_put_timex(utp, &txc);
792 	if (err)
793 		return err;
794 
795 	return ret;
796 }
797 
798 COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
799 		       struct compat_timespec __user *, tp)
800 {
801 	long err;
802 	mm_segment_t oldfs;
803 	struct timespec ts;
804 
805 	oldfs = get_fs();
806 	set_fs(KERNEL_DS);
807 	err = sys_clock_getres(which_clock,
808 			       (struct timespec __user *) &ts);
809 	set_fs(oldfs);
810 	if (!err && tp && compat_put_timespec(&ts, tp))
811 		return -EFAULT;
812 	return err;
813 }
814 
815 static long compat_clock_nanosleep_restart(struct restart_block *restart)
816 {
817 	long err;
818 	mm_segment_t oldfs;
819 	struct timespec tu;
820 	struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp;
821 
822 	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
823 	oldfs = get_fs();
824 	set_fs(KERNEL_DS);
825 	err = clock_nanosleep_restart(restart);
826 	set_fs(oldfs);
827 
828 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
829 	    compat_put_timespec(&tu, rmtp))
830 		return -EFAULT;
831 
832 	if (err == -ERESTART_RESTARTBLOCK) {
833 		restart->fn = compat_clock_nanosleep_restart;
834 		restart->nanosleep.compat_rmtp = rmtp;
835 	}
836 	return err;
837 }
838 
839 COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
840 		       struct compat_timespec __user *, rqtp,
841 		       struct compat_timespec __user *, rmtp)
842 {
843 	long err;
844 	mm_segment_t oldfs;
845 	struct timespec in, out;
846 	struct restart_block *restart;
847 
848 	if (compat_get_timespec(&in, rqtp))
849 		return -EFAULT;
850 
851 	oldfs = get_fs();
852 	set_fs(KERNEL_DS);
853 	err = sys_clock_nanosleep(which_clock, flags,
854 				  (struct timespec __user *) &in,
855 				  (struct timespec __user *) &out);
856 	set_fs(oldfs);
857 
858 	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
859 	    compat_put_timespec(&out, rmtp))
860 		return -EFAULT;
861 
862 	if (err == -ERESTART_RESTARTBLOCK) {
863 		restart = &current_thread_info()->restart_block;
864 		restart->fn = compat_clock_nanosleep_restart;
865 		restart->nanosleep.compat_rmtp = rmtp;
866 	}
867 	return err;
868 }
869 
870 /*
871  * We currently only need the following fields from the sigevent
872  * structure: sigev_value, sigev_signo, sig_notify and (sometimes
873  * sigev_notify_thread_id).  The others are handled in user mode.
874  * We also assume that copying sigev_value.sival_int is sufficient
875  * to keep all the bits of sigev_value.sival_ptr intact.
876  */
877 int get_compat_sigevent(struct sigevent *event,
878 		const struct compat_sigevent __user *u_event)
879 {
880 	memset(event, 0, sizeof(*event));
881 	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
882 		__get_user(event->sigev_value.sival_int,
883 			&u_event->sigev_value.sival_int) ||
884 		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
885 		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
886 		__get_user(event->sigev_notify_thread_id,
887 			&u_event->sigev_notify_thread_id))
888 		? -EFAULT : 0;
889 }
890 
891 long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
892 		       unsigned long bitmap_size)
893 {
894 	int i, j;
895 	unsigned long m;
896 	compat_ulong_t um;
897 	unsigned long nr_compat_longs;
898 
899 	/* align bitmap up to nearest compat_long_t boundary */
900 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
901 
902 	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
903 		return -EFAULT;
904 
905 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
906 
907 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
908 		m = 0;
909 
910 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
911 			/*
912 			 * We dont want to read past the end of the userspace
913 			 * bitmap. We must however ensure the end of the
914 			 * kernel bitmap is zeroed.
915 			 */
916 			if (nr_compat_longs-- > 0) {
917 				if (__get_user(um, umask))
918 					return -EFAULT;
919 			} else {
920 				um = 0;
921 			}
922 
923 			umask++;
924 			m |= (long)um << (j * BITS_PER_COMPAT_LONG);
925 		}
926 		*mask++ = m;
927 	}
928 
929 	return 0;
930 }
931 
932 long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask,
933 		       unsigned long bitmap_size)
934 {
935 	int i, j;
936 	unsigned long m;
937 	compat_ulong_t um;
938 	unsigned long nr_compat_longs;
939 
940 	/* align bitmap up to nearest compat_long_t boundary */
941 	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
942 
943 	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8))
944 		return -EFAULT;
945 
946 	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
947 
948 	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
949 		m = *mask++;
950 
951 		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
952 			um = m;
953 
954 			/*
955 			 * We dont want to write past the end of the userspace
956 			 * bitmap.
957 			 */
958 			if (nr_compat_longs-- > 0) {
959 				if (__put_user(um, umask))
960 					return -EFAULT;
961 			}
962 
963 			umask++;
964 			m >>= 4*sizeof(um);
965 			m >>= 4*sizeof(um);
966 		}
967 	}
968 
969 	return 0;
970 }
971 
972 void
973 sigset_from_compat(sigset_t *set, const compat_sigset_t *compat)
974 {
975 	switch (_NSIG_WORDS) {
976 	case 4: set->sig[3] = compat->sig[6] | (((long)compat->sig[7]) << 32 );
977 	case 3: set->sig[2] = compat->sig[4] | (((long)compat->sig[5]) << 32 );
978 	case 2: set->sig[1] = compat->sig[2] | (((long)compat->sig[3]) << 32 );
979 	case 1: set->sig[0] = compat->sig[0] | (((long)compat->sig[1]) << 32 );
980 	}
981 }
982 EXPORT_SYMBOL_GPL(sigset_from_compat);
983 
984 void
985 sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
986 {
987 	switch (_NSIG_WORDS) {
988 	case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
989 	case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
990 	case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
991 	case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
992 	}
993 }
994 
995 COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
996 		struct compat_siginfo __user *, uinfo,
997 		struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
998 {
999 	compat_sigset_t s32;
1000 	sigset_t s;
1001 	struct timespec t;
1002 	siginfo_t info;
1003 	long ret;
1004 
1005 	if (sigsetsize != sizeof(sigset_t))
1006 		return -EINVAL;
1007 
1008 	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
1009 		return -EFAULT;
1010 	sigset_from_compat(&s, &s32);
1011 
1012 	if (uts) {
1013 		if (compat_get_timespec(&t, uts))
1014 			return -EFAULT;
1015 	}
1016 
1017 	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1018 
1019 	if (ret > 0 && uinfo) {
1020 		if (copy_siginfo_to_user32(uinfo, &info))
1021 			ret = -EFAULT;
1022 	}
1023 
1024 	return ret;
1025 }
1026 
1027 #ifdef __ARCH_WANT_COMPAT_SYS_TIME
1028 
1029 /* compat_time_t is a 32 bit "long" and needs to get converted. */
1030 
1031 COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
1032 {
1033 	compat_time_t i;
1034 	struct timeval tv;
1035 
1036 	do_gettimeofday(&tv);
1037 	i = tv.tv_sec;
1038 
1039 	if (tloc) {
1040 		if (put_user(i,tloc))
1041 			return -EFAULT;
1042 	}
1043 	force_successful_syscall_return();
1044 	return i;
1045 }
1046 
1047 COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
1048 {
1049 	struct timespec tv;
1050 	int err;
1051 
1052 	if (get_user(tv.tv_sec, tptr))
1053 		return -EFAULT;
1054 
1055 	tv.tv_nsec = 0;
1056 
1057 	err = security_settime(&tv, NULL);
1058 	if (err)
1059 		return err;
1060 
1061 	do_settimeofday(&tv);
1062 	return 0;
1063 }
1064 
1065 #endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1066 
1067 COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)
1068 {
1069 	struct timex txc;
1070 	int err, ret;
1071 
1072 	err = compat_get_timex(&txc, utp);
1073 	if (err)
1074 		return err;
1075 
1076 	ret = do_adjtimex(&txc);
1077 
1078 	err = compat_put_timex(utp, &txc);
1079 	if (err)
1080 		return err;
1081 
1082 	return ret;
1083 }
1084 
1085 #ifdef CONFIG_NUMA
1086 COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
1087 		       compat_uptr_t __user *, pages32,
1088 		       const int __user *, nodes,
1089 		       int __user *, status,
1090 		       int, flags)
1091 {
1092 	const void __user * __user *pages;
1093 	int i;
1094 
1095 	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1096 	for (i = 0; i < nr_pages; i++) {
1097 		compat_uptr_t p;
1098 
1099 		if (get_user(p, pages32 + i) ||
1100 			put_user(compat_ptr(p), pages + i))
1101 			return -EFAULT;
1102 	}
1103 	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1104 }
1105 
1106 COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
1107 		       compat_ulong_t, maxnode,
1108 		       const compat_ulong_t __user *, old_nodes,
1109 		       const compat_ulong_t __user *, new_nodes)
1110 {
1111 	unsigned long __user *old = NULL;
1112 	unsigned long __user *new = NULL;
1113 	nodemask_t tmp_mask;
1114 	unsigned long nr_bits;
1115 	unsigned long size;
1116 
1117 	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1118 	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1119 	if (old_nodes) {
1120 		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1121 			return -EFAULT;
1122 		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1123 		if (new_nodes)
1124 			new = old + size / sizeof(unsigned long);
1125 		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1126 			return -EFAULT;
1127 	}
1128 	if (new_nodes) {
1129 		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1130 			return -EFAULT;
1131 		if (new == NULL)
1132 			new = compat_alloc_user_space(size);
1133 		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1134 			return -EFAULT;
1135 	}
1136 	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1137 }
1138 #endif
1139 
1140 COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1141 		       compat_pid_t, pid,
1142 		       struct compat_timespec __user *, interval)
1143 {
1144 	struct timespec t;
1145 	int ret;
1146 	mm_segment_t old_fs = get_fs();
1147 
1148 	set_fs(KERNEL_DS);
1149 	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1150 	set_fs(old_fs);
1151 	if (compat_put_timespec(&t, interval))
1152 		return -EFAULT;
1153 	return ret;
1154 }
1155 
1156 /*
1157  * Allocate user-space memory for the duration of a single system call,
1158  * in order to marshall parameters inside a compat thunk.
1159  */
1160 void __user *compat_alloc_user_space(unsigned long len)
1161 {
1162 	void __user *ptr;
1163 
1164 	/* If len would occupy more than half of the entire compat space... */
1165 	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1166 		return NULL;
1167 
1168 	ptr = arch_compat_alloc_user_space(len);
1169 
1170 	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1171 		return NULL;
1172 
1173 	return ptr;
1174 }
1175 EXPORT_SYMBOL_GPL(compat_alloc_user_space);
1176