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
  33static 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
  63static 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
  91COMPAT_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
 108COMPAT_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
 129static 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
 136static 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
 143static 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
 150static 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
 157int 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}
 164EXPORT_SYMBOL_GPL(compat_get_timeval);
 165
 166int 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}
 173EXPORT_SYMBOL_GPL(compat_put_timeval);
 174
 175int 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}
 182EXPORT_SYMBOL_GPL(compat_get_timespec);
 183
 184int 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}
 191EXPORT_SYMBOL_GPL(compat_put_timespec);
 192
 193int 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
 216static 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
 239COMPAT_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 = &current->restart_block;
 280
 281		restart->fn = compat_nanosleep_restart;
 282		restart->nanosleep.compat_rmtp = rmtp;
 283
 284		if (rmtp && compat_put_timespec(&rmt, rmtp))
 285			return -EFAULT;
 286	}
 
 287	return ret;
 288}
 289
 290static inline long get_compat_itimerval(struct itimerval *o,
 291		struct compat_itimerval __user *i)
 292{
 293	return (!access_ok(VERIFY_READ, i, sizeof(*i)) ||
 294		(__get_user(o->it_interval.tv_sec, &i->it_interval.tv_sec) |
 295		 __get_user(o->it_interval.tv_usec, &i->it_interval.tv_usec) |
 296		 __get_user(o->it_value.tv_sec, &i->it_value.tv_sec) |
 297		 __get_user(o->it_value.tv_usec, &i->it_value.tv_usec)));
 298}
 299
 300static inline long put_compat_itimerval(struct compat_itimerval __user *o,
 301		struct itimerval *i)
 302{
 303	return (!access_ok(VERIFY_WRITE, o, sizeof(*o)) ||
 304		(__put_user(i->it_interval.tv_sec, &o->it_interval.tv_sec) |
 305		 __put_user(i->it_interval.tv_usec, &o->it_interval.tv_usec) |
 306		 __put_user(i->it_value.tv_sec, &o->it_value.tv_sec) |
 307		 __put_user(i->it_value.tv_usec, &o->it_value.tv_usec)));
 308}
 309
 310COMPAT_SYSCALL_DEFINE2(getitimer, int, which,
 311		struct compat_itimerval __user *, it)
 312{
 313	struct itimerval kit;
 314	int error;
 315
 316	error = do_getitimer(which, &kit);
 317	if (!error && put_compat_itimerval(it, &kit))
 318		error = -EFAULT;
 319	return error;
 320}
 321
 322COMPAT_SYSCALL_DEFINE3(setitimer, int, which,
 323		struct compat_itimerval __user *, in,
 324		struct compat_itimerval __user *, out)
 325{
 326	struct itimerval kin, kout;
 327	int error;
 328
 329	if (in) {
 330		if (get_compat_itimerval(&kin, in))
 331			return -EFAULT;
 332	} else
 333		memset(&kin, 0, sizeof(kin));
 334
 335	error = do_setitimer(which, &kin, out ? &kout : NULL);
 336	if (error || !out)
 337		return error;
 338	if (put_compat_itimerval(out, &kout))
 339		return -EFAULT;
 340	return 0;
 341}
 342
 343static compat_clock_t clock_t_to_compat_clock_t(clock_t x)
 344{
 345	return compat_jiffies_to_clock_t(clock_t_to_jiffies(x));
 346}
 347
 348COMPAT_SYSCALL_DEFINE1(times, struct compat_tms __user *, tbuf)
 349{
 350	if (tbuf) {
 351		struct tms tms;
 352		struct compat_tms tmp;
 353
 354		do_sys_times(&tms);
 355		/* Convert our struct tms to the compat version. */
 356		tmp.tms_utime = clock_t_to_compat_clock_t(tms.tms_utime);
 357		tmp.tms_stime = clock_t_to_compat_clock_t(tms.tms_stime);
 358		tmp.tms_cutime = clock_t_to_compat_clock_t(tms.tms_cutime);
 359		tmp.tms_cstime = clock_t_to_compat_clock_t(tms.tms_cstime);
 360		if (copy_to_user(tbuf, &tmp, sizeof(tmp)))
 361			return -EFAULT;
 362	}
 363	force_successful_syscall_return();
 364	return compat_jiffies_to_clock_t(jiffies);
 365}
 366
 367#ifdef __ARCH_WANT_SYS_SIGPENDING
 368
 369/*
 370 * Assumption: old_sigset_t and compat_old_sigset_t are both
 371 * types that can be passed to put_user()/get_user().
 372 */
 373
 374COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set)
 375{
 376	old_sigset_t s;
 377	long ret;
 378	mm_segment_t old_fs = get_fs();
 379
 380	set_fs(KERNEL_DS);
 381	ret = sys_sigpending((old_sigset_t __user *) &s);
 382	set_fs(old_fs);
 383	if (ret == 0)
 384		ret = put_user(s, set);
 385	return ret;
 386}
 387
 388#endif
 389
 390#ifdef __ARCH_WANT_SYS_SIGPROCMASK
 391
 392/*
 393 * sys_sigprocmask SIG_SETMASK sets the first (compat) word of the
 394 * blocked set of signals to the supplied signal set
 395 */
 396static inline void compat_sig_setmask(sigset_t *blocked, compat_sigset_word set)
 397{
 398	memcpy(blocked->sig, &set, sizeof(set));
 399}
 400
 401COMPAT_SYSCALL_DEFINE3(sigprocmask, int, how,
 402		       compat_old_sigset_t __user *, nset,
 403		       compat_old_sigset_t __user *, oset)
 404{
 405	old_sigset_t old_set, new_set;
 406	sigset_t new_blocked;
 407
 408	old_set = current->blocked.sig[0];
 409
 410	if (nset) {
 411		if (get_user(new_set, nset))
 412			return -EFAULT;
 413		new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
 414
 415		new_blocked = current->blocked;
 416
 417		switch (how) {
 418		case SIG_BLOCK:
 419			sigaddsetmask(&new_blocked, new_set);
 420			break;
 421		case SIG_UNBLOCK:
 422			sigdelsetmask(&new_blocked, new_set);
 423			break;
 424		case SIG_SETMASK:
 425			compat_sig_setmask(&new_blocked, new_set);
 426			break;
 427		default:
 428			return -EINVAL;
 429		}
 430
 431		set_current_blocked(&new_blocked);
 432	}
 433
 434	if (oset) {
 435		if (put_user(old_set, oset))
 436			return -EFAULT;
 437	}
 438
 439	return 0;
 440}
 441
 442#endif
 443
 444COMPAT_SYSCALL_DEFINE2(setrlimit, unsigned int, resource,
 445		       struct compat_rlimit __user *, rlim)
 446{
 447	struct rlimit r;
 448
 449	if (!access_ok(VERIFY_READ, rlim, sizeof(*rlim)) ||
 450	    __get_user(r.rlim_cur, &rlim->rlim_cur) ||
 451	    __get_user(r.rlim_max, &rlim->rlim_max))
 452		return -EFAULT;
 453
 454	if (r.rlim_cur == COMPAT_RLIM_INFINITY)
 455		r.rlim_cur = RLIM_INFINITY;
 456	if (r.rlim_max == COMPAT_RLIM_INFINITY)
 457		r.rlim_max = RLIM_INFINITY;
 458	return do_prlimit(current, resource, &r, NULL);
 459}
 460
 461#ifdef COMPAT_RLIM_OLD_INFINITY
 462
 463COMPAT_SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource,
 464		       struct compat_rlimit __user *, rlim)
 465{
 466	struct rlimit r;
 467	int ret;
 468	mm_segment_t old_fs = get_fs();
 469
 470	set_fs(KERNEL_DS);
 471	ret = sys_old_getrlimit(resource, (struct rlimit __user *)&r);
 472	set_fs(old_fs);
 473
 474	if (!ret) {
 475		if (r.rlim_cur > COMPAT_RLIM_OLD_INFINITY)
 476			r.rlim_cur = COMPAT_RLIM_INFINITY;
 477		if (r.rlim_max > COMPAT_RLIM_OLD_INFINITY)
 478			r.rlim_max = COMPAT_RLIM_INFINITY;
 479
 480		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 481		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 482		    __put_user(r.rlim_max, &rlim->rlim_max))
 483			return -EFAULT;
 484	}
 485	return ret;
 486}
 487
 488#endif
 489
 490COMPAT_SYSCALL_DEFINE2(getrlimit, unsigned int, resource,
 491		       struct compat_rlimit __user *, rlim)
 492{
 493	struct rlimit r;
 494	int ret;
 495
 496	ret = do_prlimit(current, resource, NULL, &r);
 497	if (!ret) {
 498		if (r.rlim_cur > COMPAT_RLIM_INFINITY)
 499			r.rlim_cur = COMPAT_RLIM_INFINITY;
 500		if (r.rlim_max > COMPAT_RLIM_INFINITY)
 501			r.rlim_max = COMPAT_RLIM_INFINITY;
 502
 503		if (!access_ok(VERIFY_WRITE, rlim, sizeof(*rlim)) ||
 504		    __put_user(r.rlim_cur, &rlim->rlim_cur) ||
 505		    __put_user(r.rlim_max, &rlim->rlim_max))
 506			return -EFAULT;
 507	}
 508	return ret;
 509}
 510
 511int put_compat_rusage(const struct rusage *r, struct compat_rusage __user *ru)
 512{
 513	if (!access_ok(VERIFY_WRITE, ru, sizeof(*ru)) ||
 514	    __put_user(r->ru_utime.tv_sec, &ru->ru_utime.tv_sec) ||
 515	    __put_user(r->ru_utime.tv_usec, &ru->ru_utime.tv_usec) ||
 516	    __put_user(r->ru_stime.tv_sec, &ru->ru_stime.tv_sec) ||
 517	    __put_user(r->ru_stime.tv_usec, &ru->ru_stime.tv_usec) ||
 518	    __put_user(r->ru_maxrss, &ru->ru_maxrss) ||
 519	    __put_user(r->ru_ixrss, &ru->ru_ixrss) ||
 520	    __put_user(r->ru_idrss, &ru->ru_idrss) ||
 521	    __put_user(r->ru_isrss, &ru->ru_isrss) ||
 522	    __put_user(r->ru_minflt, &ru->ru_minflt) ||
 523	    __put_user(r->ru_majflt, &ru->ru_majflt) ||
 524	    __put_user(r->ru_nswap, &ru->ru_nswap) ||
 525	    __put_user(r->ru_inblock, &ru->ru_inblock) ||
 526	    __put_user(r->ru_oublock, &ru->ru_oublock) ||
 527	    __put_user(r->ru_msgsnd, &ru->ru_msgsnd) ||
 528	    __put_user(r->ru_msgrcv, &ru->ru_msgrcv) ||
 529	    __put_user(r->ru_nsignals, &ru->ru_nsignals) ||
 530	    __put_user(r->ru_nvcsw, &ru->ru_nvcsw) ||
 531	    __put_user(r->ru_nivcsw, &ru->ru_nivcsw))
 532		return -EFAULT;
 533	return 0;
 534}
 535
 536COMPAT_SYSCALL_DEFINE4(wait4,
 537	compat_pid_t, pid,
 538	compat_uint_t __user *, stat_addr,
 539	int, options,
 540	struct compat_rusage __user *, ru)
 541{
 542	if (!ru) {
 543		return sys_wait4(pid, stat_addr, options, NULL);
 544	} else {
 545		struct rusage r;
 546		int ret;
 547		unsigned int status;
 548		mm_segment_t old_fs = get_fs();
 549
 550		set_fs (KERNEL_DS);
 551		ret = sys_wait4(pid,
 552				(stat_addr ?
 553				 (unsigned int __user *) &status : NULL),
 554				options, (struct rusage __user *) &r);
 555		set_fs (old_fs);
 556
 557		if (ret > 0) {
 558			if (put_compat_rusage(&r, ru))
 559				return -EFAULT;
 560			if (stat_addr && put_user(status, stat_addr))
 561				return -EFAULT;
 562		}
 563		return ret;
 564	}
 565}
 566
 567COMPAT_SYSCALL_DEFINE5(waitid,
 568		int, which, compat_pid_t, pid,
 569		struct compat_siginfo __user *, uinfo, int, options,
 570		struct compat_rusage __user *, uru)
 571{
 572	siginfo_t info;
 573	struct rusage ru;
 574	long ret;
 575	mm_segment_t old_fs = get_fs();
 576
 577	memset(&info, 0, sizeof(info));
 578
 579	set_fs(KERNEL_DS);
 580	ret = sys_waitid(which, pid, (siginfo_t __user *)&info, options,
 581			 uru ? (struct rusage __user *)&ru : NULL);
 582	set_fs(old_fs);
 583
 584	if ((ret < 0) || (info.si_signo == 0))
 585		return ret;
 586
 587	if (uru) {
 588		/* sys_waitid() overwrites everything in ru */
 589		if (COMPAT_USE_64BIT_TIME)
 590			ret = copy_to_user(uru, &ru, sizeof(ru));
 591		else
 592			ret = put_compat_rusage(&ru, uru);
 593		if (ret)
 594			return -EFAULT;
 595	}
 596
 597	BUG_ON(info.si_code & __SI_MASK);
 598	info.si_code |= __SI_CHLD;
 599	return copy_siginfo_to_user32(uinfo, &info);
 600}
 601
 602static int compat_get_user_cpu_mask(compat_ulong_t __user *user_mask_ptr,
 603				    unsigned len, struct cpumask *new_mask)
 604{
 605	unsigned long *k;
 606
 607	if (len < cpumask_size())
 608		memset(new_mask, 0, cpumask_size());
 609	else if (len > cpumask_size())
 610		len = cpumask_size();
 611
 612	k = cpumask_bits(new_mask);
 613	return compat_get_bitmap(k, user_mask_ptr, len * 8);
 614}
 615
 616COMPAT_SYSCALL_DEFINE3(sched_setaffinity, compat_pid_t, pid,
 617		       unsigned int, len,
 618		       compat_ulong_t __user *, user_mask_ptr)
 619{
 620	cpumask_var_t new_mask;
 621	int retval;
 622
 623	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
 624		return -ENOMEM;
 625
 626	retval = compat_get_user_cpu_mask(user_mask_ptr, len, new_mask);
 627	if (retval)
 628		goto out;
 629
 630	retval = sched_setaffinity(pid, new_mask);
 631out:
 632	free_cpumask_var(new_mask);
 633	return retval;
 634}
 635
 636COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t,  pid, unsigned int, len,
 637		       compat_ulong_t __user *, user_mask_ptr)
 638{
 639	int ret;
 640	cpumask_var_t mask;
 641
 642	if ((len * BITS_PER_BYTE) < nr_cpu_ids)
 643		return -EINVAL;
 644	if (len & (sizeof(compat_ulong_t)-1))
 645		return -EINVAL;
 646
 647	if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 648		return -ENOMEM;
 649
 650	ret = sched_getaffinity(pid, mask);
 651	if (ret == 0) {
 652		size_t retlen = min_t(size_t, len, cpumask_size());
 653
 654		if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
 655			ret = -EFAULT;
 656		else
 657			ret = retlen;
 658	}
 659	free_cpumask_var(mask);
 660
 661	return ret;
 662}
 663
 664int get_compat_itimerspec(struct itimerspec *dst,
 665			  const struct compat_itimerspec __user *src)
 666{
 667	if (__compat_get_timespec(&dst->it_interval, &src->it_interval) ||
 668	    __compat_get_timespec(&dst->it_value, &src->it_value))
 669		return -EFAULT;
 670	return 0;
 671}
 672
 673int put_compat_itimerspec(struct compat_itimerspec __user *dst,
 674			  const struct itimerspec *src)
 675{
 676	if (__compat_put_timespec(&src->it_interval, &dst->it_interval) ||
 677	    __compat_put_timespec(&src->it_value, &dst->it_value))
 678		return -EFAULT;
 679	return 0;
 680}
 681
 682COMPAT_SYSCALL_DEFINE3(timer_create, clockid_t, which_clock,
 683		       struct compat_sigevent __user *, timer_event_spec,
 684		       timer_t __user *, created_timer_id)
 685{
 686	struct sigevent __user *event = NULL;
 687
 688	if (timer_event_spec) {
 689		struct sigevent kevent;
 690
 691		event = compat_alloc_user_space(sizeof(*event));
 692		if (get_compat_sigevent(&kevent, timer_event_spec) ||
 693		    copy_to_user(event, &kevent, sizeof(*event)))
 694			return -EFAULT;
 695	}
 696
 697	return sys_timer_create(which_clock, event, created_timer_id);
 698}
 699
 700COMPAT_SYSCALL_DEFINE4(timer_settime, timer_t, timer_id, int, flags,
 701		       struct compat_itimerspec __user *, new,
 702		       struct compat_itimerspec __user *, old)
 703{
 704	long err;
 705	mm_segment_t oldfs;
 706	struct itimerspec newts, oldts;
 707
 708	if (!new)
 709		return -EINVAL;
 710	if (get_compat_itimerspec(&newts, new))
 711		return -EFAULT;
 712	oldfs = get_fs();
 713	set_fs(KERNEL_DS);
 714	err = sys_timer_settime(timer_id, flags,
 715				(struct itimerspec __user *) &newts,
 716				(struct itimerspec __user *) &oldts);
 717	set_fs(oldfs);
 718	if (!err && old && put_compat_itimerspec(old, &oldts))
 719		return -EFAULT;
 720	return err;
 721}
 722
 723COMPAT_SYSCALL_DEFINE2(timer_gettime, timer_t, timer_id,
 724		       struct compat_itimerspec __user *, setting)
 725{
 726	long err;
 727	mm_segment_t oldfs;
 728	struct itimerspec ts;
 729
 730	oldfs = get_fs();
 731	set_fs(KERNEL_DS);
 732	err = sys_timer_gettime(timer_id,
 733				(struct itimerspec __user *) &ts);
 734	set_fs(oldfs);
 735	if (!err && put_compat_itimerspec(setting, &ts))
 736		return -EFAULT;
 737	return err;
 738}
 739
 740COMPAT_SYSCALL_DEFINE2(clock_settime, 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	if (compat_get_timespec(&ts, tp))
 748		return -EFAULT;
 749	oldfs = get_fs();
 750	set_fs(KERNEL_DS);
 751	err = sys_clock_settime(which_clock,
 752				(struct timespec __user *) &ts);
 753	set_fs(oldfs);
 754	return err;
 755}
 756
 757COMPAT_SYSCALL_DEFINE2(clock_gettime, clockid_t, which_clock,
 758		       struct compat_timespec __user *, tp)
 759{
 760	long err;
 761	mm_segment_t oldfs;
 762	struct timespec ts;
 763
 764	oldfs = get_fs();
 765	set_fs(KERNEL_DS);
 766	err = sys_clock_gettime(which_clock,
 767				(struct timespec __user *) &ts);
 768	set_fs(oldfs);
 769	if (!err && compat_put_timespec(&ts, tp))
 770		return -EFAULT;
 771	return err;
 772}
 773
 774COMPAT_SYSCALL_DEFINE2(clock_adjtime, clockid_t, which_clock,
 775		       struct compat_timex __user *, utp)
 776{
 777	struct timex txc;
 778	mm_segment_t oldfs;
 779	int err, ret;
 780
 781	err = compat_get_timex(&txc, utp);
 782	if (err)
 783		return err;
 784
 785	oldfs = get_fs();
 786	set_fs(KERNEL_DS);
 787	ret = sys_clock_adjtime(which_clock, (struct timex __user *) &txc);
 788	set_fs(oldfs);
 789
 790	err = compat_put_timex(utp, &txc);
 791	if (err)
 792		return err;
 793
 794	return ret;
 795}
 796
 797COMPAT_SYSCALL_DEFINE2(clock_getres, clockid_t, which_clock,
 798		       struct compat_timespec __user *, tp)
 799{
 800	long err;
 801	mm_segment_t oldfs;
 802	struct timespec ts;
 803
 804	oldfs = get_fs();
 805	set_fs(KERNEL_DS);
 806	err = sys_clock_getres(which_clock,
 807			       (struct timespec __user *) &ts);
 808	set_fs(oldfs);
 809	if (!err && tp && compat_put_timespec(&ts, tp))
 810		return -EFAULT;
 811	return err;
 812}
 813
 814static long compat_clock_nanosleep_restart(struct restart_block *restart)
 815{
 816	long err;
 817	mm_segment_t oldfs;
 818	struct timespec tu;
 819	struct compat_timespec __user *rmtp = restart->nanosleep.compat_rmtp;
 820
 821	restart->nanosleep.rmtp = (struct timespec __user *) &tu;
 822	oldfs = get_fs();
 823	set_fs(KERNEL_DS);
 824	err = clock_nanosleep_restart(restart);
 825	set_fs(oldfs);
 826
 827	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 828	    compat_put_timespec(&tu, rmtp))
 829		return -EFAULT;
 830
 831	if (err == -ERESTART_RESTARTBLOCK) {
 832		restart->fn = compat_clock_nanosleep_restart;
 833		restart->nanosleep.compat_rmtp = rmtp;
 834	}
 835	return err;
 836}
 837
 838COMPAT_SYSCALL_DEFINE4(clock_nanosleep, clockid_t, which_clock, int, flags,
 839		       struct compat_timespec __user *, rqtp,
 840		       struct compat_timespec __user *, rmtp)
 841{
 842	long err;
 843	mm_segment_t oldfs;
 844	struct timespec in, out;
 845	struct restart_block *restart;
 846
 847	if (compat_get_timespec(&in, rqtp))
 848		return -EFAULT;
 849
 850	oldfs = get_fs();
 851	set_fs(KERNEL_DS);
 852	err = sys_clock_nanosleep(which_clock, flags,
 853				  (struct timespec __user *) &in,
 854				  (struct timespec __user *) &out);
 855	set_fs(oldfs);
 856
 857	if ((err == -ERESTART_RESTARTBLOCK) && rmtp &&
 858	    compat_put_timespec(&out, rmtp))
 859		return -EFAULT;
 860
 861	if (err == -ERESTART_RESTARTBLOCK) {
 862		restart = &current->restart_block;
 863		restart->fn = compat_clock_nanosleep_restart;
 864		restart->nanosleep.compat_rmtp = rmtp;
 865	}
 866	return err;
 867}
 868
 869/*
 870 * We currently only need the following fields from the sigevent
 871 * structure: sigev_value, sigev_signo, sig_notify and (sometimes
 872 * sigev_notify_thread_id).  The others are handled in user mode.
 873 * We also assume that copying sigev_value.sival_int is sufficient
 874 * to keep all the bits of sigev_value.sival_ptr intact.
 875 */
 876int get_compat_sigevent(struct sigevent *event,
 877		const struct compat_sigevent __user *u_event)
 878{
 879	memset(event, 0, sizeof(*event));
 880	return (!access_ok(VERIFY_READ, u_event, sizeof(*u_event)) ||
 881		__get_user(event->sigev_value.sival_int,
 882			&u_event->sigev_value.sival_int) ||
 883		__get_user(event->sigev_signo, &u_event->sigev_signo) ||
 884		__get_user(event->sigev_notify, &u_event->sigev_notify) ||
 885		__get_user(event->sigev_notify_thread_id,
 886			&u_event->sigev_notify_thread_id))
 887		? -EFAULT : 0;
 888}
 889
 890long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask,
 891		       unsigned long bitmap_size)
 892{
 893	int i, j;
 894	unsigned long m;
 895	compat_ulong_t um;
 896	unsigned long nr_compat_longs;
 897
 898	/* align bitmap up to nearest compat_long_t boundary */
 899	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
 900
 901	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8))
 902		return -EFAULT;
 903
 904	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
 905
 906	for (i = 0; i < BITS_TO_LONGS(bitmap_size); i++) {
 907		m = 0;
 908
 909		for (j = 0; j < sizeof(m)/sizeof(um); j++) {
 910			/*
 911			 * We dont want to read past the end of the userspace
 912			 * bitmap. We must however ensure the end of the
 913			 * kernel bitmap is zeroed.
 914			 */
 915			if (nr_compat_longs) {
 916				nr_compat_longs--;
 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
 932long 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) {
 959				nr_compat_longs--;
 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
 973void
 974sigset_from_compat(sigset_t *set, const 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}
 983EXPORT_SYMBOL_GPL(sigset_from_compat);
 984
 985void
 986sigset_to_compat(compat_sigset_t *compat, const sigset_t *set)
 987{
 988	switch (_NSIG_WORDS) {
 989	case 4: compat->sig[7] = (set->sig[3] >> 32); compat->sig[6] = set->sig[3];
 990	case 3: compat->sig[5] = (set->sig[2] >> 32); compat->sig[4] = set->sig[2];
 991	case 2: compat->sig[3] = (set->sig[1] >> 32); compat->sig[2] = set->sig[1];
 992	case 1: compat->sig[1] = (set->sig[0] >> 32); compat->sig[0] = set->sig[0];
 993	}
 994}
 995
 996COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese,
 997		struct compat_siginfo __user *, uinfo,
 998		struct compat_timespec __user *, uts, compat_size_t, sigsetsize)
 999{
1000	compat_sigset_t s32;
1001	sigset_t s;
1002	struct timespec t;
1003	siginfo_t info;
1004	long ret;
1005
1006	if (sigsetsize != sizeof(sigset_t))
1007		return -EINVAL;
1008
1009	if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t)))
1010		return -EFAULT;
1011	sigset_from_compat(&s, &s32);
1012
1013	if (uts) {
1014		if (compat_get_timespec(&t, uts))
1015			return -EFAULT;
1016	}
1017
1018	ret = do_sigtimedwait(&s, &info, uts ? &t : NULL);
1019
1020	if (ret > 0 && uinfo) {
1021		if (copy_siginfo_to_user32(uinfo, &info))
1022			ret = -EFAULT;
1023	}
1024
1025	return ret;
1026}
1027
1028#ifdef __ARCH_WANT_COMPAT_SYS_TIME
1029
1030/* compat_time_t is a 32 bit "long" and needs to get converted. */
1031
1032COMPAT_SYSCALL_DEFINE1(time, compat_time_t __user *, tloc)
1033{
1034	compat_time_t i;
1035	struct timeval tv;
1036
1037	do_gettimeofday(&tv);
1038	i = tv.tv_sec;
1039
1040	if (tloc) {
1041		if (put_user(i,tloc))
1042			return -EFAULT;
1043	}
1044	force_successful_syscall_return();
1045	return i;
1046}
1047
1048COMPAT_SYSCALL_DEFINE1(stime, compat_time_t __user *, tptr)
1049{
1050	struct timespec tv;
1051	int err;
1052
1053	if (get_user(tv.tv_sec, tptr))
1054		return -EFAULT;
1055
1056	tv.tv_nsec = 0;
1057
1058	err = security_settime(&tv, NULL);
1059	if (err)
1060		return err;
1061
1062	do_settimeofday(&tv);
1063	return 0;
1064}
1065
1066#endif /* __ARCH_WANT_COMPAT_SYS_TIME */
1067
1068COMPAT_SYSCALL_DEFINE1(adjtimex, struct compat_timex __user *, utp)
1069{
1070	struct timex txc;
1071	int err, ret;
1072
1073	err = compat_get_timex(&txc, utp);
1074	if (err)
1075		return err;
1076
1077	ret = do_adjtimex(&txc);
1078
1079	err = compat_put_timex(utp, &txc);
1080	if (err)
1081		return err;
1082
1083	return ret;
1084}
1085
1086#ifdef CONFIG_NUMA
1087COMPAT_SYSCALL_DEFINE6(move_pages, pid_t, pid, compat_ulong_t, nr_pages,
1088		       compat_uptr_t __user *, pages32,
1089		       const int __user *, nodes,
1090		       int __user *, status,
1091		       int, flags)
1092{
1093	const void __user * __user *pages;
1094	int i;
1095
1096	pages = compat_alloc_user_space(nr_pages * sizeof(void *));
1097	for (i = 0; i < nr_pages; i++) {
1098		compat_uptr_t p;
1099
1100		if (get_user(p, pages32 + i) ||
1101			put_user(compat_ptr(p), pages + i))
1102			return -EFAULT;
1103	}
1104	return sys_move_pages(pid, nr_pages, pages, nodes, status, flags);
1105}
1106
1107COMPAT_SYSCALL_DEFINE4(migrate_pages, compat_pid_t, pid,
1108		       compat_ulong_t, maxnode,
1109		       const compat_ulong_t __user *, old_nodes,
1110		       const compat_ulong_t __user *, new_nodes)
1111{
1112	unsigned long __user *old = NULL;
1113	unsigned long __user *new = NULL;
1114	nodemask_t tmp_mask;
1115	unsigned long nr_bits;
1116	unsigned long size;
1117
1118	nr_bits = min_t(unsigned long, maxnode - 1, MAX_NUMNODES);
1119	size = ALIGN(nr_bits, BITS_PER_LONG) / 8;
1120	if (old_nodes) {
1121		if (compat_get_bitmap(nodes_addr(tmp_mask), old_nodes, nr_bits))
1122			return -EFAULT;
1123		old = compat_alloc_user_space(new_nodes ? size * 2 : size);
1124		if (new_nodes)
1125			new = old + size / sizeof(unsigned long);
1126		if (copy_to_user(old, nodes_addr(tmp_mask), size))
1127			return -EFAULT;
1128	}
1129	if (new_nodes) {
1130		if (compat_get_bitmap(nodes_addr(tmp_mask), new_nodes, nr_bits))
1131			return -EFAULT;
1132		if (new == NULL)
1133			new = compat_alloc_user_space(size);
1134		if (copy_to_user(new, nodes_addr(tmp_mask), size))
1135			return -EFAULT;
1136	}
1137	return sys_migrate_pages(pid, nr_bits + 1, old, new);
1138}
1139#endif
1140
1141COMPAT_SYSCALL_DEFINE2(sched_rr_get_interval,
1142		       compat_pid_t, pid,
1143		       struct compat_timespec __user *, interval)
1144{
1145	struct timespec t;
1146	int ret;
1147	mm_segment_t old_fs = get_fs();
1148
1149	set_fs(KERNEL_DS);
1150	ret = sys_sched_rr_get_interval(pid, (struct timespec __user *)&t);
1151	set_fs(old_fs);
1152	if (compat_put_timespec(&t, interval))
1153		return -EFAULT;
1154	return ret;
1155}
1156
1157/*
1158 * Allocate user-space memory for the duration of a single system call,
1159 * in order to marshall parameters inside a compat thunk.
1160 */
1161void __user *compat_alloc_user_space(unsigned long len)
1162{
1163	void __user *ptr;
1164
1165	/* If len would occupy more than half of the entire compat space... */
1166	if (unlikely(len > (((compat_uptr_t)~0) >> 1)))
1167		return NULL;
1168
1169	ptr = arch_compat_alloc_user_space(len);
1170
1171	if (unlikely(!access_ok(VERIFY_WRITE, ptr, len)))
1172		return NULL;
1173
1174	return ptr;
1175}
1176EXPORT_SYMBOL_GPL(compat_alloc_user_space);