xref: /openbmc/linux/arch/s390/kernel/compat_linux.c (revision b627b4ed)
1 /*
2  *  arch/s390x/kernel/linux32.c
3  *
4  *  S390 version
5  *    Copyright (C) 2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
7  *               Gerhard Tonn (ton@de.ibm.com)
8  *               Thomas Spatzier (tspat@de.ibm.com)
9  *
10  *  Conversion between 31bit and 64bit native syscalls.
11  *
12  * Heavily inspired by the 32-bit Sparc compat code which is
13  * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
14  * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
15  *
16  */
17 
18 
19 #include <linux/kernel.h>
20 #include <linux/sched.h>
21 #include <linux/fs.h>
22 #include <linux/mm.h>
23 #include <linux/file.h>
24 #include <linux/signal.h>
25 #include <linux/resource.h>
26 #include <linux/times.h>
27 #include <linux/utsname.h>
28 #include <linux/smp.h>
29 #include <linux/smp_lock.h>
30 #include <linux/sem.h>
31 #include <linux/msg.h>
32 #include <linux/shm.h>
33 #include <linux/slab.h>
34 #include <linux/uio.h>
35 #include <linux/nfs_fs.h>
36 #include <linux/quota.h>
37 #include <linux/module.h>
38 #include <linux/sunrpc/svc.h>
39 #include <linux/nfsd/nfsd.h>
40 #include <linux/nfsd/cache.h>
41 #include <linux/nfsd/xdr.h>
42 #include <linux/nfsd/syscall.h>
43 #include <linux/poll.h>
44 #include <linux/personality.h>
45 #include <linux/stat.h>
46 #include <linux/filter.h>
47 #include <linux/highmem.h>
48 #include <linux/highuid.h>
49 #include <linux/mman.h>
50 #include <linux/ipv6.h>
51 #include <linux/in.h>
52 #include <linux/icmpv6.h>
53 #include <linux/syscalls.h>
54 #include <linux/sysctl.h>
55 #include <linux/binfmts.h>
56 #include <linux/capability.h>
57 #include <linux/compat.h>
58 #include <linux/vfs.h>
59 #include <linux/ptrace.h>
60 #include <linux/fadvise.h>
61 #include <linux/ipc.h>
62 
63 #include <asm/types.h>
64 #include <asm/uaccess.h>
65 
66 #include <net/scm.h>
67 #include <net/sock.h>
68 
69 #include "compat_linux.h"
70 
71 long psw_user32_bits	= (PSW_BASE32_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
72 			   PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
73 			   PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
74 long psw32_user_bits	= (PSW32_BASE_BITS | PSW32_MASK_DAT | PSW32_ASC_HOME |
75 			   PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
76 			   PSW32_MASK_PSTATE);
77 
78 /* For this source file, we want overflow handling. */
79 
80 #undef high2lowuid
81 #undef high2lowgid
82 #undef low2highuid
83 #undef low2highgid
84 #undef SET_UID16
85 #undef SET_GID16
86 #undef NEW_TO_OLD_UID
87 #undef NEW_TO_OLD_GID
88 #undef SET_OLDSTAT_UID
89 #undef SET_OLDSTAT_GID
90 #undef SET_STAT_UID
91 #undef SET_STAT_GID
92 
93 #define high2lowuid(uid) ((uid) > 65535) ? (u16)overflowuid : (u16)(uid)
94 #define high2lowgid(gid) ((gid) > 65535) ? (u16)overflowgid : (u16)(gid)
95 #define low2highuid(uid) ((uid) == (u16)-1) ? (uid_t)-1 : (uid_t)(uid)
96 #define low2highgid(gid) ((gid) == (u16)-1) ? (gid_t)-1 : (gid_t)(gid)
97 #define SET_UID16(var, uid)	var = high2lowuid(uid)
98 #define SET_GID16(var, gid)	var = high2lowgid(gid)
99 #define NEW_TO_OLD_UID(uid)	high2lowuid(uid)
100 #define NEW_TO_OLD_GID(gid)	high2lowgid(gid)
101 #define SET_OLDSTAT_UID(stat, uid)	(stat).st_uid = high2lowuid(uid)
102 #define SET_OLDSTAT_GID(stat, gid)	(stat).st_gid = high2lowgid(gid)
103 #define SET_STAT_UID(stat, uid)		(stat).st_uid = high2lowuid(uid)
104 #define SET_STAT_GID(stat, gid)		(stat).st_gid = high2lowgid(gid)
105 
106 asmlinkage long sys32_chown16(const char __user * filename, u16 user, u16 group)
107 {
108 	return sys_chown(filename, low2highuid(user), low2highgid(group));
109 }
110 
111 asmlinkage long sys32_lchown16(const char __user * filename, u16 user, u16 group)
112 {
113 	return sys_lchown(filename, low2highuid(user), low2highgid(group));
114 }
115 
116 asmlinkage long sys32_fchown16(unsigned int fd, u16 user, u16 group)
117 {
118 	return sys_fchown(fd, low2highuid(user), low2highgid(group));
119 }
120 
121 asmlinkage long sys32_setregid16(u16 rgid, u16 egid)
122 {
123 	return sys_setregid(low2highgid(rgid), low2highgid(egid));
124 }
125 
126 asmlinkage long sys32_setgid16(u16 gid)
127 {
128 	return sys_setgid((gid_t)gid);
129 }
130 
131 asmlinkage long sys32_setreuid16(u16 ruid, u16 euid)
132 {
133 	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
134 }
135 
136 asmlinkage long sys32_setuid16(u16 uid)
137 {
138 	return sys_setuid((uid_t)uid);
139 }
140 
141 asmlinkage long sys32_setresuid16(u16 ruid, u16 euid, u16 suid)
142 {
143 	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
144 		low2highuid(suid));
145 }
146 
147 asmlinkage long sys32_getresuid16(u16 __user *ruid, u16 __user *euid, u16 __user *suid)
148 {
149 	int retval;
150 
151 	if (!(retval = put_user(high2lowuid(current->cred->uid), ruid)) &&
152 	    !(retval = put_user(high2lowuid(current->cred->euid), euid)))
153 		retval = put_user(high2lowuid(current->cred->suid), suid);
154 
155 	return retval;
156 }
157 
158 asmlinkage long sys32_setresgid16(u16 rgid, u16 egid, u16 sgid)
159 {
160 	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
161 		low2highgid(sgid));
162 }
163 
164 asmlinkage long sys32_getresgid16(u16 __user *rgid, u16 __user *egid, u16 __user *sgid)
165 {
166 	int retval;
167 
168 	if (!(retval = put_user(high2lowgid(current->cred->gid), rgid)) &&
169 	    !(retval = put_user(high2lowgid(current->cred->egid), egid)))
170 		retval = put_user(high2lowgid(current->cred->sgid), sgid);
171 
172 	return retval;
173 }
174 
175 asmlinkage long sys32_setfsuid16(u16 uid)
176 {
177 	return sys_setfsuid((uid_t)uid);
178 }
179 
180 asmlinkage long sys32_setfsgid16(u16 gid)
181 {
182 	return sys_setfsgid((gid_t)gid);
183 }
184 
185 static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
186 {
187 	int i;
188 	u16 group;
189 
190 	for (i = 0; i < group_info->ngroups; i++) {
191 		group = (u16)GROUP_AT(group_info, i);
192 		if (put_user(group, grouplist+i))
193 			return -EFAULT;
194 	}
195 
196 	return 0;
197 }
198 
199 static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
200 {
201 	int i;
202 	u16 group;
203 
204 	for (i = 0; i < group_info->ngroups; i++) {
205 		if (get_user(group, grouplist+i))
206 			return  -EFAULT;
207 		GROUP_AT(group_info, i) = (gid_t)group;
208 	}
209 
210 	return 0;
211 }
212 
213 asmlinkage long sys32_getgroups16(int gidsetsize, u16 __user *grouplist)
214 {
215 	int i;
216 
217 	if (gidsetsize < 0)
218 		return -EINVAL;
219 
220 	get_group_info(current->cred->group_info);
221 	i = current->cred->group_info->ngroups;
222 	if (gidsetsize) {
223 		if (i > gidsetsize) {
224 			i = -EINVAL;
225 			goto out;
226 		}
227 		if (groups16_to_user(grouplist, current->cred->group_info)) {
228 			i = -EFAULT;
229 			goto out;
230 		}
231 	}
232 out:
233 	put_group_info(current->cred->group_info);
234 	return i;
235 }
236 
237 asmlinkage long sys32_setgroups16(int gidsetsize, u16 __user *grouplist)
238 {
239 	struct group_info *group_info;
240 	int retval;
241 
242 	if (!capable(CAP_SETGID))
243 		return -EPERM;
244 	if ((unsigned)gidsetsize > NGROUPS_MAX)
245 		return -EINVAL;
246 
247 	group_info = groups_alloc(gidsetsize);
248 	if (!group_info)
249 		return -ENOMEM;
250 	retval = groups16_from_user(group_info, grouplist);
251 	if (retval) {
252 		put_group_info(group_info);
253 		return retval;
254 	}
255 
256 	retval = set_current_groups(group_info);
257 	put_group_info(group_info);
258 
259 	return retval;
260 }
261 
262 asmlinkage long sys32_getuid16(void)
263 {
264 	return high2lowuid(current->cred->uid);
265 }
266 
267 asmlinkage long sys32_geteuid16(void)
268 {
269 	return high2lowuid(current->cred->euid);
270 }
271 
272 asmlinkage long sys32_getgid16(void)
273 {
274 	return high2lowgid(current->cred->gid);
275 }
276 
277 asmlinkage long sys32_getegid16(void)
278 {
279 	return high2lowgid(current->cred->egid);
280 }
281 
282 /*
283  * sys32_ipc() is the de-multiplexer for the SysV IPC calls in 32bit emulation.
284  *
285  * This is really horribly ugly.
286  */
287 #ifdef CONFIG_SYSVIPC
288 asmlinkage long sys32_ipc(u32 call, int first, int second, int third, u32 ptr)
289 {
290 	if (call >> 16)		/* hack for backward compatibility */
291 		return -EINVAL;
292 
293 	call &= 0xffff;
294 
295 	switch (call) {
296 	case SEMTIMEDOP:
297 		return compat_sys_semtimedop(first, compat_ptr(ptr),
298 					     second, compat_ptr(third));
299 	case SEMOP:
300 		/* struct sembuf is the same on 32 and 64bit :)) */
301 		return sys_semtimedop(first, compat_ptr(ptr),
302 				      second, NULL);
303 	case SEMGET:
304 		return sys_semget(first, second, third);
305 	case SEMCTL:
306 		return compat_sys_semctl(first, second, third,
307 					 compat_ptr(ptr));
308 	case MSGSND:
309 		return compat_sys_msgsnd(first, second, third,
310 					 compat_ptr(ptr));
311 	case MSGRCV:
312 		return compat_sys_msgrcv(first, second, 0, third,
313 					 0, compat_ptr(ptr));
314 	case MSGGET:
315 		return sys_msgget((key_t) first, second);
316 	case MSGCTL:
317 		return compat_sys_msgctl(first, second, compat_ptr(ptr));
318 	case SHMAT:
319 		return compat_sys_shmat(first, second, third,
320 					0, compat_ptr(ptr));
321 	case SHMDT:
322 		return sys_shmdt(compat_ptr(ptr));
323 	case SHMGET:
324 		return sys_shmget(first, (unsigned)second, third);
325 	case SHMCTL:
326 		return compat_sys_shmctl(first, second, compat_ptr(ptr));
327 	}
328 
329 	return -ENOSYS;
330 }
331 #endif
332 
333 asmlinkage long sys32_truncate64(const char __user * path, unsigned long high, unsigned long low)
334 {
335 	if ((int)high < 0)
336 		return -EINVAL;
337 	else
338 		return sys_truncate(path, (high << 32) | low);
339 }
340 
341 asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long high, unsigned long low)
342 {
343 	if ((int)high < 0)
344 		return -EINVAL;
345 	else
346 		return sys_ftruncate(fd, (high << 32) | low);
347 }
348 
349 asmlinkage long sys32_sched_rr_get_interval(compat_pid_t pid,
350 				struct compat_timespec __user *interval)
351 {
352 	struct timespec t;
353 	int ret;
354 	mm_segment_t old_fs = get_fs ();
355 
356 	set_fs (KERNEL_DS);
357 	ret = sys_sched_rr_get_interval(pid,
358 					(struct timespec __force __user *) &t);
359 	set_fs (old_fs);
360 	if (put_compat_timespec(&t, interval))
361 		return -EFAULT;
362 	return ret;
363 }
364 
365 asmlinkage long sys32_rt_sigprocmask(int how, compat_sigset_t __user *set,
366 			compat_sigset_t __user *oset, size_t sigsetsize)
367 {
368 	sigset_t s;
369 	compat_sigset_t s32;
370 	int ret;
371 	mm_segment_t old_fs = get_fs();
372 
373 	if (set) {
374 		if (copy_from_user (&s32, set, sizeof(compat_sigset_t)))
375 			return -EFAULT;
376 		switch (_NSIG_WORDS) {
377 		case 4: s.sig[3] = s32.sig[6] | (((long)s32.sig[7]) << 32);
378 		case 3: s.sig[2] = s32.sig[4] | (((long)s32.sig[5]) << 32);
379 		case 2: s.sig[1] = s32.sig[2] | (((long)s32.sig[3]) << 32);
380 		case 1: s.sig[0] = s32.sig[0] | (((long)s32.sig[1]) << 32);
381 		}
382 	}
383 	set_fs (KERNEL_DS);
384 	ret = sys_rt_sigprocmask(how,
385 				 set ? (sigset_t __force __user *) &s : NULL,
386 				 oset ? (sigset_t __force __user *) &s : NULL,
387 				 sigsetsize);
388 	set_fs (old_fs);
389 	if (ret) return ret;
390 	if (oset) {
391 		switch (_NSIG_WORDS) {
392 		case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
393 		case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
394 		case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
395 		case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
396 		}
397 		if (copy_to_user (oset, &s32, sizeof(compat_sigset_t)))
398 			return -EFAULT;
399 	}
400 	return 0;
401 }
402 
403 asmlinkage long sys32_rt_sigpending(compat_sigset_t __user *set,
404 				size_t sigsetsize)
405 {
406 	sigset_t s;
407 	compat_sigset_t s32;
408 	int ret;
409 	mm_segment_t old_fs = get_fs();
410 
411 	set_fs (KERNEL_DS);
412 	ret = sys_rt_sigpending((sigset_t __force __user *) &s, sigsetsize);
413 	set_fs (old_fs);
414 	if (!ret) {
415 		switch (_NSIG_WORDS) {
416 		case 4: s32.sig[7] = (s.sig[3] >> 32); s32.sig[6] = s.sig[3];
417 		case 3: s32.sig[5] = (s.sig[2] >> 32); s32.sig[4] = s.sig[2];
418 		case 2: s32.sig[3] = (s.sig[1] >> 32); s32.sig[2] = s.sig[1];
419 		case 1: s32.sig[1] = (s.sig[0] >> 32); s32.sig[0] = s.sig[0];
420 		}
421 		if (copy_to_user (set, &s32, sizeof(compat_sigset_t)))
422 			return -EFAULT;
423 	}
424 	return ret;
425 }
426 
427 asmlinkage long
428 sys32_rt_sigqueueinfo(int pid, int sig, compat_siginfo_t __user *uinfo)
429 {
430 	siginfo_t info;
431 	int ret;
432 	mm_segment_t old_fs = get_fs();
433 
434 	if (copy_siginfo_from_user32(&info, uinfo))
435 		return -EFAULT;
436 	set_fs (KERNEL_DS);
437 	ret = sys_rt_sigqueueinfo(pid, sig, (siginfo_t __force __user *) &info);
438 	set_fs (old_fs);
439 	return ret;
440 }
441 
442 /*
443  * sys32_execve() executes a new program after the asm stub has set
444  * things up for us.  This should basically do what I want it to.
445  */
446 asmlinkage long sys32_execve(void)
447 {
448 	struct pt_regs *regs = task_pt_regs(current);
449 	char *filename;
450 	unsigned long result;
451 	int rc;
452 
453 	filename = getname(compat_ptr(regs->orig_gpr2));
454 	if (IS_ERR(filename)) {
455 		result = PTR_ERR(filename);
456                 goto out;
457 	}
458 	rc = compat_do_execve(filename, compat_ptr(regs->gprs[3]),
459 			      compat_ptr(regs->gprs[4]), regs);
460 	if (rc) {
461 		result = rc;
462 		goto out_putname;
463 	}
464 	task_lock(current);
465 	current->ptrace &= ~PT_DTRACE;
466 	task_unlock(current);
467 	current->thread.fp_regs.fpc=0;
468 	asm volatile("sfpc %0,0" : : "d" (0));
469 	result = regs->gprs[2];
470 out_putname:
471         putname(filename);
472 out:
473 	return result;
474 }
475 
476 
477 #ifdef CONFIG_MODULES
478 
479 asmlinkage long
480 sys32_init_module(void __user *umod, unsigned long len,
481 		const char __user *uargs)
482 {
483 	return sys_init_module(umod, len, uargs);
484 }
485 
486 asmlinkage long
487 sys32_delete_module(const char __user *name_user, unsigned int flags)
488 {
489 	return sys_delete_module(name_user, flags);
490 }
491 
492 #else /* CONFIG_MODULES */
493 
494 asmlinkage long
495 sys32_init_module(void __user *umod, unsigned long len,
496 		const char __user *uargs)
497 {
498 	return -ENOSYS;
499 }
500 
501 asmlinkage long
502 sys32_delete_module(const char __user *name_user, unsigned int flags)
503 {
504 	return -ENOSYS;
505 }
506 
507 #endif  /* CONFIG_MODULES */
508 
509 asmlinkage long sys32_pread64(unsigned int fd, char __user *ubuf,
510 				size_t count, u32 poshi, u32 poslo)
511 {
512 	if ((compat_ssize_t) count < 0)
513 		return -EINVAL;
514 	return sys_pread64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
515 }
516 
517 asmlinkage long sys32_pwrite64(unsigned int fd, const char __user *ubuf,
518 				size_t count, u32 poshi, u32 poslo)
519 {
520 	if ((compat_ssize_t) count < 0)
521 		return -EINVAL;
522 	return sys_pwrite64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
523 }
524 
525 asmlinkage compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 count)
526 {
527 	return sys_readahead(fd, ((loff_t)AA(offhi) << 32) | AA(offlo), count);
528 }
529 
530 asmlinkage long sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, size_t count)
531 {
532 	mm_segment_t old_fs = get_fs();
533 	int ret;
534 	off_t of;
535 
536 	if (offset && get_user(of, offset))
537 		return -EFAULT;
538 
539 	set_fs(KERNEL_DS);
540 	ret = sys_sendfile(out_fd, in_fd,
541 			   offset ? (off_t __force __user *) &of : NULL, count);
542 	set_fs(old_fs);
543 
544 	if (offset && put_user(of, offset))
545 		return -EFAULT;
546 
547 	return ret;
548 }
549 
550 asmlinkage long sys32_sendfile64(int out_fd, int in_fd,
551 				compat_loff_t __user *offset, s32 count)
552 {
553 	mm_segment_t old_fs = get_fs();
554 	int ret;
555 	loff_t lof;
556 
557 	if (offset && get_user(lof, offset))
558 		return -EFAULT;
559 
560 	set_fs(KERNEL_DS);
561 	ret = sys_sendfile64(out_fd, in_fd,
562 			     offset ? (loff_t __force __user *) &lof : NULL,
563 			     count);
564 	set_fs(old_fs);
565 
566 	if (offset && put_user(lof, offset))
567 		return -EFAULT;
568 
569 	return ret;
570 }
571 
572 #ifdef CONFIG_SYSCTL_SYSCALL
573 struct __sysctl_args32 {
574 	u32 name;
575 	int nlen;
576 	u32 oldval;
577 	u32 oldlenp;
578 	u32 newval;
579 	u32 newlen;
580 	u32 __unused[4];
581 };
582 
583 asmlinkage long sys32_sysctl(struct __sysctl_args32 __user *args)
584 {
585 	struct __sysctl_args32 tmp;
586 	int error;
587 	size_t oldlen;
588 	size_t __user *oldlenp = NULL;
589 	unsigned long addr = (((unsigned long)&args->__unused[0]) + 7) & ~7;
590 
591 	if (copy_from_user(&tmp, args, sizeof(tmp)))
592 		return -EFAULT;
593 
594 	if (tmp.oldval && tmp.oldlenp) {
595 		/* Duh, this is ugly and might not work if sysctl_args
596 		   is in read-only memory, but do_sysctl does indirectly
597 		   a lot of uaccess in both directions and we'd have to
598 		   basically copy the whole sysctl.c here, and
599 		   glibc's __sysctl uses rw memory for the structure
600 		   anyway.  */
601 		if (get_user(oldlen, (u32 __user *)compat_ptr(tmp.oldlenp)) ||
602 		    put_user(oldlen, (size_t __user *)addr))
603 			return -EFAULT;
604 		oldlenp = (size_t __user *)addr;
605 	}
606 
607 	lock_kernel();
608 	error = do_sysctl(compat_ptr(tmp.name), tmp.nlen, compat_ptr(tmp.oldval),
609 			  oldlenp, compat_ptr(tmp.newval), tmp.newlen);
610 	unlock_kernel();
611 	if (oldlenp) {
612 		if (!error) {
613 			if (get_user(oldlen, (size_t __user *)addr) ||
614 			    put_user(oldlen, (u32 __user *)compat_ptr(tmp.oldlenp)))
615 				error = -EFAULT;
616 		}
617 		if (copy_to_user(args->__unused, tmp.__unused,
618 				 sizeof(tmp.__unused)))
619 			error = -EFAULT;
620 	}
621 	return error;
622 }
623 #endif
624 
625 struct stat64_emu31 {
626 	unsigned long long  st_dev;
627 	unsigned int    __pad1;
628 #define STAT64_HAS_BROKEN_ST_INO        1
629 	u32             __st_ino;
630 	unsigned int    st_mode;
631 	unsigned int    st_nlink;
632 	u32             st_uid;
633 	u32             st_gid;
634 	unsigned long long  st_rdev;
635 	unsigned int    __pad3;
636 	long            st_size;
637 	u32             st_blksize;
638 	unsigned char   __pad4[4];
639 	u32             __pad5;     /* future possible st_blocks high bits */
640 	u32             st_blocks;  /* Number 512-byte blocks allocated. */
641 	u32             st_atime;
642 	u32             __pad6;
643 	u32             st_mtime;
644 	u32             __pad7;
645 	u32             st_ctime;
646 	u32             __pad8;     /* will be high 32 bits of ctime someday */
647 	unsigned long   st_ino;
648 };
649 
650 static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
651 {
652 	struct stat64_emu31 tmp;
653 
654 	memset(&tmp, 0, sizeof(tmp));
655 
656 	tmp.st_dev = huge_encode_dev(stat->dev);
657 	tmp.st_ino = stat->ino;
658 	tmp.__st_ino = (u32)stat->ino;
659 	tmp.st_mode = stat->mode;
660 	tmp.st_nlink = (unsigned int)stat->nlink;
661 	tmp.st_uid = stat->uid;
662 	tmp.st_gid = stat->gid;
663 	tmp.st_rdev = huge_encode_dev(stat->rdev);
664 	tmp.st_size = stat->size;
665 	tmp.st_blksize = (u32)stat->blksize;
666 	tmp.st_blocks = (u32)stat->blocks;
667 	tmp.st_atime = (u32)stat->atime.tv_sec;
668 	tmp.st_mtime = (u32)stat->mtime.tv_sec;
669 	tmp.st_ctime = (u32)stat->ctime.tv_sec;
670 
671 	return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
672 }
673 
674 asmlinkage long sys32_stat64(char __user * filename, struct stat64_emu31 __user * statbuf)
675 {
676 	struct kstat stat;
677 	int ret = vfs_stat(filename, &stat);
678 	if (!ret)
679 		ret = cp_stat64(statbuf, &stat);
680 	return ret;
681 }
682 
683 asmlinkage long sys32_lstat64(char __user * filename, struct stat64_emu31 __user * statbuf)
684 {
685 	struct kstat stat;
686 	int ret = vfs_lstat(filename, &stat);
687 	if (!ret)
688 		ret = cp_stat64(statbuf, &stat);
689 	return ret;
690 }
691 
692 asmlinkage long sys32_fstat64(unsigned long fd, struct stat64_emu31 __user * statbuf)
693 {
694 	struct kstat stat;
695 	int ret = vfs_fstat(fd, &stat);
696 	if (!ret)
697 		ret = cp_stat64(statbuf, &stat);
698 	return ret;
699 }
700 
701 asmlinkage long sys32_fstatat64(unsigned int dfd, char __user *filename,
702 				struct stat64_emu31 __user* statbuf, int flag)
703 {
704 	struct kstat stat;
705 	int error = -EINVAL;
706 
707 	if ((flag & ~AT_SYMLINK_NOFOLLOW) != 0)
708 		goto out;
709 
710 	if (flag & AT_SYMLINK_NOFOLLOW)
711 		error = vfs_lstat_fd(dfd, filename, &stat);
712 	else
713 		error = vfs_stat_fd(dfd, filename, &stat);
714 
715 	if (!error)
716 		error = cp_stat64(statbuf, &stat);
717 out:
718 	return error;
719 }
720 
721 /*
722  * Linux/i386 didn't use to be able to handle more than
723  * 4 system call parameters, so these system calls used a memory
724  * block for parameter passing..
725  */
726 
727 struct mmap_arg_struct_emu31 {
728 	u32	addr;
729 	u32	len;
730 	u32	prot;
731 	u32	flags;
732 	u32	fd;
733 	u32	offset;
734 };
735 
736 /* common code for old and new mmaps */
737 static inline long do_mmap2(
738 	unsigned long addr, unsigned long len,
739 	unsigned long prot, unsigned long flags,
740 	unsigned long fd, unsigned long pgoff)
741 {
742 	struct file * file = NULL;
743 	unsigned long error = -EBADF;
744 
745 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
746 	if (!(flags & MAP_ANONYMOUS)) {
747 		file = fget(fd);
748 		if (!file)
749 			goto out;
750 	}
751 
752 	down_write(&current->mm->mmap_sem);
753 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
754 	if (!IS_ERR((void *) error) && error + len >= 0x80000000ULL) {
755 		/* Result is out of bounds.  */
756 		do_munmap(current->mm, addr, len);
757 		error = -ENOMEM;
758 	}
759 	up_write(&current->mm->mmap_sem);
760 
761 	if (file)
762 		fput(file);
763 out:
764 	return error;
765 }
766 
767 
768 asmlinkage unsigned long
769 old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
770 {
771 	struct mmap_arg_struct_emu31 a;
772 	int error = -EFAULT;
773 
774 	if (copy_from_user(&a, arg, sizeof(a)))
775 		goto out;
776 
777 	error = -EINVAL;
778 	if (a.offset & ~PAGE_MASK)
779 		goto out;
780 
781 	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
782 out:
783 	return error;
784 }
785 
786 asmlinkage long
787 sys32_mmap2(struct mmap_arg_struct_emu31 __user *arg)
788 {
789 	struct mmap_arg_struct_emu31 a;
790 	int error = -EFAULT;
791 
792 	if (copy_from_user(&a, arg, sizeof(a)))
793 		goto out;
794 	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
795 out:
796 	return error;
797 }
798 
799 asmlinkage long sys32_read(unsigned int fd, char __user * buf, size_t count)
800 {
801 	if ((compat_ssize_t) count < 0)
802 		return -EINVAL;
803 
804 	return sys_read(fd, buf, count);
805 }
806 
807 asmlinkage long sys32_write(unsigned int fd, char __user * buf, size_t count)
808 {
809 	if ((compat_ssize_t) count < 0)
810 		return -EINVAL;
811 
812 	return sys_write(fd, buf, count);
813 }
814 
815 asmlinkage long sys32_clone(void)
816 {
817 	struct pt_regs *regs = task_pt_regs(current);
818 	unsigned long clone_flags;
819 	unsigned long newsp;
820 	int __user *parent_tidptr, *child_tidptr;
821 
822 	clone_flags = regs->gprs[3] & 0xffffffffUL;
823 	newsp = regs->orig_gpr2 & 0x7fffffffUL;
824 	parent_tidptr = compat_ptr(regs->gprs[4]);
825 	child_tidptr = compat_ptr(regs->gprs[5]);
826 	if (!newsp)
827 		newsp = regs->gprs[15];
828 	return do_fork(clone_flags, newsp, regs, 0,
829 		       parent_tidptr, child_tidptr);
830 }
831 
832 /*
833  * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
834  * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
835  * because the 31 bit values differ from the 64 bit values.
836  */
837 
838 asmlinkage long
839 sys32_fadvise64(int fd, loff_t offset, size_t len, int advise)
840 {
841 	if (advise == 4)
842 		advise = POSIX_FADV_DONTNEED;
843 	else if (advise == 5)
844 		advise = POSIX_FADV_NOREUSE;
845 	return sys_fadvise64(fd, offset, len, advise);
846 }
847 
848 struct fadvise64_64_args {
849 	int fd;
850 	long long offset;
851 	long long len;
852 	int advice;
853 };
854 
855 asmlinkage long
856 sys32_fadvise64_64(struct fadvise64_64_args __user *args)
857 {
858 	struct fadvise64_64_args a;
859 
860 	if ( copy_from_user(&a, args, sizeof(a)) )
861 		return -EFAULT;
862 	if (a.advice == 4)
863 		a.advice = POSIX_FADV_DONTNEED;
864 	else if (a.advice == 5)
865 		a.advice = POSIX_FADV_NOREUSE;
866 	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
867 }
868