compat_linux.c revision d7b5427cec79d993459c162db67eac9e22135e8b
1/*
2 *  S390 version
3 *    Copyright IBM Corp. 2000
4 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
5 *               Gerhard Tonn (ton@de.ibm.com)
6 *               Thomas Spatzier (tspat@de.ibm.com)
7 *
8 *  Conversion between 31bit and 64bit native syscalls.
9 *
10 * Heavily inspired by the 32-bit Sparc compat code which is
11 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
12 * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
13 *
14 */
15
16
17#include <linux/kernel.h>
18#include <linux/sched.h>
19#include <linux/fs.h>
20#include <linux/mm.h>
21#include <linux/file.h>
22#include <linux/signal.h>
23#include <linux/resource.h>
24#include <linux/times.h>
25#include <linux/smp.h>
26#include <linux/sem.h>
27#include <linux/msg.h>
28#include <linux/shm.h>
29#include <linux/uio.h>
30#include <linux/quota.h>
31#include <linux/module.h>
32#include <linux/poll.h>
33#include <linux/personality.h>
34#include <linux/stat.h>
35#include <linux/filter.h>
36#include <linux/highmem.h>
37#include <linux/highuid.h>
38#include <linux/mman.h>
39#include <linux/ipv6.h>
40#include <linux/in.h>
41#include <linux/icmpv6.h>
42#include <linux/syscalls.h>
43#include <linux/sysctl.h>
44#include <linux/binfmts.h>
45#include <linux/capability.h>
46#include <linux/compat.h>
47#include <linux/vfs.h>
48#include <linux/ptrace.h>
49#include <linux/fadvise.h>
50#include <linux/ipc.h>
51#include <linux/slab.h>
52
53#include <asm/types.h>
54#include <asm/uaccess.h>
55
56#include <net/scm.h>
57#include <net/sock.h>
58
59#include "compat_linux.h"
60
61u32 psw32_user_bits = PSW32_MASK_DAT | PSW32_MASK_IO | PSW32_MASK_EXT |
62		      PSW32_DEFAULT_KEY | PSW32_MASK_BASE | PSW32_MASK_MCHECK |
63		      PSW32_MASK_PSTATE | PSW32_ASC_HOME;
64
65/* For this source file, we want overflow handling. */
66
67#undef high2lowuid
68#undef high2lowgid
69#undef low2highuid
70#undef low2highgid
71#undef SET_UID16
72#undef SET_GID16
73#undef NEW_TO_OLD_UID
74#undef NEW_TO_OLD_GID
75#undef SET_OLDSTAT_UID
76#undef SET_OLDSTAT_GID
77#undef SET_STAT_UID
78#undef SET_STAT_GID
79
80#define high2lowuid(uid) ((uid) > 65535) ? (u16)overflowuid : (u16)(uid)
81#define high2lowgid(gid) ((gid) > 65535) ? (u16)overflowgid : (u16)(gid)
82#define low2highuid(uid) ((uid) == (u16)-1) ? (uid_t)-1 : (uid_t)(uid)
83#define low2highgid(gid) ((gid) == (u16)-1) ? (gid_t)-1 : (gid_t)(gid)
84#define SET_UID16(var, uid)	var = high2lowuid(uid)
85#define SET_GID16(var, gid)	var = high2lowgid(gid)
86#define NEW_TO_OLD_UID(uid)	high2lowuid(uid)
87#define NEW_TO_OLD_GID(gid)	high2lowgid(gid)
88#define SET_OLDSTAT_UID(stat, uid)	(stat).st_uid = high2lowuid(uid)
89#define SET_OLDSTAT_GID(stat, gid)	(stat).st_gid = high2lowgid(gid)
90#define SET_STAT_UID(stat, uid)		(stat).st_uid = high2lowuid(uid)
91#define SET_STAT_GID(stat, gid)		(stat).st_gid = high2lowgid(gid)
92
93asmlinkage long sys32_chown16(const char __user * filename, u16 user, u16 group)
94{
95	return sys_chown(filename, low2highuid(user), low2highgid(group));
96}
97
98asmlinkage long sys32_lchown16(const char __user * filename, u16 user, u16 group)
99{
100	return sys_lchown(filename, low2highuid(user), low2highgid(group));
101}
102
103asmlinkage long sys32_fchown16(unsigned int fd, u16 user, u16 group)
104{
105	return sys_fchown(fd, low2highuid(user), low2highgid(group));
106}
107
108asmlinkage long sys32_setregid16(u16 rgid, u16 egid)
109{
110	return sys_setregid(low2highgid(rgid), low2highgid(egid));
111}
112
113asmlinkage long sys32_setgid16(u16 gid)
114{
115	return sys_setgid((gid_t)gid);
116}
117
118asmlinkage long sys32_setreuid16(u16 ruid, u16 euid)
119{
120	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
121}
122
123asmlinkage long sys32_setuid16(u16 uid)
124{
125	return sys_setuid((uid_t)uid);
126}
127
128asmlinkage long sys32_setresuid16(u16 ruid, u16 euid, u16 suid)
129{
130	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
131		low2highuid(suid));
132}
133
134asmlinkage long sys32_getresuid16(u16 __user *ruidp, u16 __user *euidp, u16 __user *suidp)
135{
136	const struct cred *cred = current_cred();
137	int retval;
138	u16 ruid, euid, suid;
139
140	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
141	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
142	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
143
144	if (!(retval   = put_user(ruid, ruidp)) &&
145	    !(retval   = put_user(euid, euidp)))
146		retval = put_user(suid, suidp);
147
148	return retval;
149}
150
151asmlinkage long sys32_setresgid16(u16 rgid, u16 egid, u16 sgid)
152{
153	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
154		low2highgid(sgid));
155}
156
157asmlinkage long sys32_getresgid16(u16 __user *rgidp, u16 __user *egidp, u16 __user *sgidp)
158{
159	const struct cred *cred = current_cred();
160	int retval;
161	u16 rgid, egid, sgid;
162
163	rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
164	egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
165	sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
166
167	if (!(retval   = put_user(rgid, rgidp)) &&
168	    !(retval   = put_user(egid, egidp)))
169		retval = put_user(sgid, sgidp);
170
171	return retval;
172}
173
174asmlinkage long sys32_setfsuid16(u16 uid)
175{
176	return sys_setfsuid((uid_t)uid);
177}
178
179asmlinkage long sys32_setfsgid16(u16 gid)
180{
181	return sys_setfsgid((gid_t)gid);
182}
183
184static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
185{
186	struct user_namespace *user_ns = current_user_ns();
187	int i;
188	u16 group;
189	kgid_t kgid;
190
191	for (i = 0; i < group_info->ngroups; i++) {
192		kgid = GROUP_AT(group_info, i);
193		group = (u16)from_kgid_munged(user_ns, kgid);
194		if (put_user(group, grouplist+i))
195			return -EFAULT;
196	}
197
198	return 0;
199}
200
201static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
202{
203	struct user_namespace *user_ns = current_user_ns();
204	int i;
205	u16 group;
206	kgid_t kgid;
207
208	for (i = 0; i < group_info->ngroups; i++) {
209		if (get_user(group, grouplist+i))
210			return  -EFAULT;
211
212		kgid = make_kgid(user_ns, (gid_t)group);
213		if (!gid_valid(kgid))
214			return -EINVAL;
215
216		GROUP_AT(group_info, i) = kgid;
217	}
218
219	return 0;
220}
221
222asmlinkage long sys32_getgroups16(int gidsetsize, u16 __user *grouplist)
223{
224	int i;
225
226	if (gidsetsize < 0)
227		return -EINVAL;
228
229	get_group_info(current->cred->group_info);
230	i = current->cred->group_info->ngroups;
231	if (gidsetsize) {
232		if (i > gidsetsize) {
233			i = -EINVAL;
234			goto out;
235		}
236		if (groups16_to_user(grouplist, current->cred->group_info)) {
237			i = -EFAULT;
238			goto out;
239		}
240	}
241out:
242	put_group_info(current->cred->group_info);
243	return i;
244}
245
246asmlinkage long sys32_setgroups16(int gidsetsize, u16 __user *grouplist)
247{
248	struct group_info *group_info;
249	int retval;
250
251	if (!capable(CAP_SETGID))
252		return -EPERM;
253	if ((unsigned)gidsetsize > NGROUPS_MAX)
254		return -EINVAL;
255
256	group_info = groups_alloc(gidsetsize);
257	if (!group_info)
258		return -ENOMEM;
259	retval = groups16_from_user(group_info, grouplist);
260	if (retval) {
261		put_group_info(group_info);
262		return retval;
263	}
264
265	retval = set_current_groups(group_info);
266	put_group_info(group_info);
267
268	return retval;
269}
270
271asmlinkage long sys32_getuid16(void)
272{
273	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
274}
275
276asmlinkage long sys32_geteuid16(void)
277{
278	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
279}
280
281asmlinkage long sys32_getgid16(void)
282{
283	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
284}
285
286asmlinkage long sys32_getegid16(void)
287{
288	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
289}
290
291/*
292 * sys32_ipc() is the de-multiplexer for the SysV IPC calls in 32bit emulation.
293 *
294 * This is really horribly ugly.
295 */
296#ifdef CONFIG_SYSVIPC
297asmlinkage long sys32_ipc(u32 call, int first, int second, int third, u32 ptr)
298{
299	if (call >> 16)		/* hack for backward compatibility */
300		return -EINVAL;
301	switch (call) {
302	case SEMTIMEDOP:
303		return compat_sys_semtimedop(first, compat_ptr(ptr),
304					     second, compat_ptr(third));
305	case SEMOP:
306		/* struct sembuf is the same on 32 and 64bit :)) */
307		return sys_semtimedop(first, compat_ptr(ptr),
308				      second, NULL);
309	case SEMGET:
310		return sys_semget(first, second, third);
311	case SEMCTL:
312		return compat_sys_semctl(first, second, third,
313					 compat_ptr(ptr));
314	case MSGSND:
315		return compat_sys_msgsnd(first, second, third,
316					 compat_ptr(ptr));
317	case MSGRCV:
318		return compat_sys_msgrcv(first, second, 0, third,
319					 0, compat_ptr(ptr));
320	case MSGGET:
321		return sys_msgget((key_t) first, second);
322	case MSGCTL:
323		return compat_sys_msgctl(first, second, compat_ptr(ptr));
324	case SHMAT:
325		return compat_sys_shmat(first, second, third,
326					0, compat_ptr(ptr));
327	case SHMDT:
328		return sys_shmdt(compat_ptr(ptr));
329	case SHMGET:
330		return sys_shmget(first, (unsigned)second, third);
331	case SHMCTL:
332		return compat_sys_shmctl(first, second, compat_ptr(ptr));
333	}
334
335	return -ENOSYS;
336}
337#endif
338
339asmlinkage long sys32_truncate64(const char __user * path, unsigned long high, unsigned long low)
340{
341	if ((int)high < 0)
342		return -EINVAL;
343	else
344		return sys_truncate(path, (high << 32) | low);
345}
346
347asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long high, unsigned long low)
348{
349	if ((int)high < 0)
350		return -EINVAL;
351	else
352		return sys_ftruncate(fd, (high << 32) | low);
353}
354
355asmlinkage long sys32_pread64(unsigned int fd, char __user *ubuf,
356				size_t count, u32 poshi, u32 poslo)
357{
358	if ((compat_ssize_t) count < 0)
359		return -EINVAL;
360	return sys_pread64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
361}
362
363asmlinkage long sys32_pwrite64(unsigned int fd, const char __user *ubuf,
364				size_t count, u32 poshi, u32 poslo)
365{
366	if ((compat_ssize_t) count < 0)
367		return -EINVAL;
368	return sys_pwrite64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
369}
370
371asmlinkage compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 count)
372{
373	return sys_readahead(fd, ((loff_t)AA(offhi) << 32) | AA(offlo), count);
374}
375
376asmlinkage long sys32_sendfile(int out_fd, int in_fd, compat_off_t __user *offset, size_t count)
377{
378	mm_segment_t old_fs = get_fs();
379	int ret;
380	off_t of;
381
382	if (offset && get_user(of, offset))
383		return -EFAULT;
384
385	set_fs(KERNEL_DS);
386	ret = sys_sendfile(out_fd, in_fd,
387			   offset ? (off_t __force __user *) &of : NULL, count);
388	set_fs(old_fs);
389
390	if (offset && put_user(of, offset))
391		return -EFAULT;
392
393	return ret;
394}
395
396asmlinkage long sys32_sendfile64(int out_fd, int in_fd,
397				compat_loff_t __user *offset, s32 count)
398{
399	mm_segment_t old_fs = get_fs();
400	int ret;
401	loff_t lof;
402
403	if (offset && get_user(lof, offset))
404		return -EFAULT;
405
406	set_fs(KERNEL_DS);
407	ret = sys_sendfile64(out_fd, in_fd,
408			     offset ? (loff_t __force __user *) &lof : NULL,
409			     count);
410	set_fs(old_fs);
411
412	if (offset && put_user(lof, offset))
413		return -EFAULT;
414
415	return ret;
416}
417
418struct stat64_emu31 {
419	unsigned long long  st_dev;
420	unsigned int    __pad1;
421#define STAT64_HAS_BROKEN_ST_INO        1
422	u32             __st_ino;
423	unsigned int    st_mode;
424	unsigned int    st_nlink;
425	u32             st_uid;
426	u32             st_gid;
427	unsigned long long  st_rdev;
428	unsigned int    __pad3;
429	long            st_size;
430	u32             st_blksize;
431	unsigned char   __pad4[4];
432	u32             __pad5;     /* future possible st_blocks high bits */
433	u32             st_blocks;  /* Number 512-byte blocks allocated. */
434	u32             st_atime;
435	u32             __pad6;
436	u32             st_mtime;
437	u32             __pad7;
438	u32             st_ctime;
439	u32             __pad8;     /* will be high 32 bits of ctime someday */
440	unsigned long   st_ino;
441};
442
443static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
444{
445	struct stat64_emu31 tmp;
446
447	memset(&tmp, 0, sizeof(tmp));
448
449	tmp.st_dev = huge_encode_dev(stat->dev);
450	tmp.st_ino = stat->ino;
451	tmp.__st_ino = (u32)stat->ino;
452	tmp.st_mode = stat->mode;
453	tmp.st_nlink = (unsigned int)stat->nlink;
454	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
455	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
456	tmp.st_rdev = huge_encode_dev(stat->rdev);
457	tmp.st_size = stat->size;
458	tmp.st_blksize = (u32)stat->blksize;
459	tmp.st_blocks = (u32)stat->blocks;
460	tmp.st_atime = (u32)stat->atime.tv_sec;
461	tmp.st_mtime = (u32)stat->mtime.tv_sec;
462	tmp.st_ctime = (u32)stat->ctime.tv_sec;
463
464	return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
465}
466
467asmlinkage long sys32_stat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
468{
469	struct kstat stat;
470	int ret = vfs_stat(filename, &stat);
471	if (!ret)
472		ret = cp_stat64(statbuf, &stat);
473	return ret;
474}
475
476asmlinkage long sys32_lstat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
477{
478	struct kstat stat;
479	int ret = vfs_lstat(filename, &stat);
480	if (!ret)
481		ret = cp_stat64(statbuf, &stat);
482	return ret;
483}
484
485asmlinkage long sys32_fstat64(unsigned long fd, struct stat64_emu31 __user * statbuf)
486{
487	struct kstat stat;
488	int ret = vfs_fstat(fd, &stat);
489	if (!ret)
490		ret = cp_stat64(statbuf, &stat);
491	return ret;
492}
493
494asmlinkage long sys32_fstatat64(unsigned int dfd, const char __user *filename,
495				struct stat64_emu31 __user* statbuf, int flag)
496{
497	struct kstat stat;
498	int error;
499
500	error = vfs_fstatat(dfd, filename, &stat, flag);
501	if (error)
502		return error;
503	return cp_stat64(statbuf, &stat);
504}
505
506/*
507 * Linux/i386 didn't use to be able to handle more than
508 * 4 system call parameters, so these system calls used a memory
509 * block for parameter passing..
510 */
511
512struct mmap_arg_struct_emu31 {
513	compat_ulong_t addr;
514	compat_ulong_t len;
515	compat_ulong_t prot;
516	compat_ulong_t flags;
517	compat_ulong_t fd;
518	compat_ulong_t offset;
519};
520
521asmlinkage unsigned long old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
522{
523	struct mmap_arg_struct_emu31 a;
524
525	if (copy_from_user(&a, arg, sizeof(a)))
526		return -EFAULT;
527	if (a.offset & ~PAGE_MASK)
528		return -EINVAL;
529	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
530			      a.offset >> PAGE_SHIFT);
531}
532
533asmlinkage long sys32_mmap2(struct mmap_arg_struct_emu31 __user *arg)
534{
535	struct mmap_arg_struct_emu31 a;
536
537	if (copy_from_user(&a, arg, sizeof(a)))
538		return -EFAULT;
539	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
540}
541
542asmlinkage long sys32_read(unsigned int fd, char __user * buf, size_t count)
543{
544	if ((compat_ssize_t) count < 0)
545		return -EINVAL;
546
547	return sys_read(fd, buf, count);
548}
549
550asmlinkage long sys32_write(unsigned int fd, const char __user * buf, size_t count)
551{
552	if ((compat_ssize_t) count < 0)
553		return -EINVAL;
554
555	return sys_write(fd, buf, count);
556}
557
558/*
559 * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
560 * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
561 * because the 31 bit values differ from the 64 bit values.
562 */
563
564asmlinkage long
565sys32_fadvise64(int fd, loff_t offset, size_t len, int advise)
566{
567	if (advise == 4)
568		advise = POSIX_FADV_DONTNEED;
569	else if (advise == 5)
570		advise = POSIX_FADV_NOREUSE;
571	return sys_fadvise64(fd, offset, len, advise);
572}
573
574struct fadvise64_64_args {
575	int fd;
576	long long offset;
577	long long len;
578	int advice;
579};
580
581asmlinkage long
582sys32_fadvise64_64(struct fadvise64_64_args __user *args)
583{
584	struct fadvise64_64_args a;
585
586	if ( copy_from_user(&a, args, sizeof(a)) )
587		return -EFAULT;
588	if (a.advice == 4)
589		a.advice = POSIX_FADV_DONTNEED;
590	else if (a.advice == 5)
591		a.advice = POSIX_FADV_NOREUSE;
592	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
593}
594