xref: /openbmc/linux/arch/s390/kernel/compat_linux.c (revision 79f08d9e)
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 
61 /* For this source file, we want overflow handling. */
62 
63 #undef high2lowuid
64 #undef high2lowgid
65 #undef low2highuid
66 #undef low2highgid
67 #undef SET_UID16
68 #undef SET_GID16
69 #undef NEW_TO_OLD_UID
70 #undef NEW_TO_OLD_GID
71 #undef SET_OLDSTAT_UID
72 #undef SET_OLDSTAT_GID
73 #undef SET_STAT_UID
74 #undef SET_STAT_GID
75 
76 #define high2lowuid(uid) ((uid) > 65535) ? (u16)overflowuid : (u16)(uid)
77 #define high2lowgid(gid) ((gid) > 65535) ? (u16)overflowgid : (u16)(gid)
78 #define low2highuid(uid) ((uid) == (u16)-1) ? (uid_t)-1 : (uid_t)(uid)
79 #define low2highgid(gid) ((gid) == (u16)-1) ? (gid_t)-1 : (gid_t)(gid)
80 #define SET_UID16(var, uid)	var = high2lowuid(uid)
81 #define SET_GID16(var, gid)	var = high2lowgid(gid)
82 #define NEW_TO_OLD_UID(uid)	high2lowuid(uid)
83 #define NEW_TO_OLD_GID(gid)	high2lowgid(gid)
84 #define SET_OLDSTAT_UID(stat, uid)	(stat).st_uid = high2lowuid(uid)
85 #define SET_OLDSTAT_GID(stat, gid)	(stat).st_gid = high2lowgid(gid)
86 #define SET_STAT_UID(stat, uid)		(stat).st_uid = high2lowuid(uid)
87 #define SET_STAT_GID(stat, gid)		(stat).st_gid = high2lowgid(gid)
88 
89 asmlinkage long sys32_chown16(const char __user * filename, u16 user, u16 group)
90 {
91 	return sys_chown(filename, low2highuid(user), low2highgid(group));
92 }
93 
94 asmlinkage long sys32_lchown16(const char __user * filename, u16 user, u16 group)
95 {
96 	return sys_lchown(filename, low2highuid(user), low2highgid(group));
97 }
98 
99 asmlinkage long sys32_fchown16(unsigned int fd, u16 user, u16 group)
100 {
101 	return sys_fchown(fd, low2highuid(user), low2highgid(group));
102 }
103 
104 asmlinkage long sys32_setregid16(u16 rgid, u16 egid)
105 {
106 	return sys_setregid(low2highgid(rgid), low2highgid(egid));
107 }
108 
109 asmlinkage long sys32_setgid16(u16 gid)
110 {
111 	return sys_setgid((gid_t)gid);
112 }
113 
114 asmlinkage long sys32_setreuid16(u16 ruid, u16 euid)
115 {
116 	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
117 }
118 
119 asmlinkage long sys32_setuid16(u16 uid)
120 {
121 	return sys_setuid((uid_t)uid);
122 }
123 
124 asmlinkage long sys32_setresuid16(u16 ruid, u16 euid, u16 suid)
125 {
126 	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
127 		low2highuid(suid));
128 }
129 
130 asmlinkage long sys32_getresuid16(u16 __user *ruidp, u16 __user *euidp, u16 __user *suidp)
131 {
132 	const struct cred *cred = current_cred();
133 	int retval;
134 	u16 ruid, euid, suid;
135 
136 	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
137 	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
138 	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
139 
140 	if (!(retval   = put_user(ruid, ruidp)) &&
141 	    !(retval   = put_user(euid, euidp)))
142 		retval = put_user(suid, suidp);
143 
144 	return retval;
145 }
146 
147 asmlinkage long sys32_setresgid16(u16 rgid, u16 egid, u16 sgid)
148 {
149 	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
150 		low2highgid(sgid));
151 }
152 
153 asmlinkage long sys32_getresgid16(u16 __user *rgidp, u16 __user *egidp, u16 __user *sgidp)
154 {
155 	const struct cred *cred = current_cred();
156 	int retval;
157 	u16 rgid, egid, sgid;
158 
159 	rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
160 	egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
161 	sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
162 
163 	if (!(retval   = put_user(rgid, rgidp)) &&
164 	    !(retval   = put_user(egid, egidp)))
165 		retval = put_user(sgid, sgidp);
166 
167 	return retval;
168 }
169 
170 asmlinkage long sys32_setfsuid16(u16 uid)
171 {
172 	return sys_setfsuid((uid_t)uid);
173 }
174 
175 asmlinkage long sys32_setfsgid16(u16 gid)
176 {
177 	return sys_setfsgid((gid_t)gid);
178 }
179 
180 static int groups16_to_user(u16 __user *grouplist, struct group_info *group_info)
181 {
182 	struct user_namespace *user_ns = current_user_ns();
183 	int i;
184 	u16 group;
185 	kgid_t kgid;
186 
187 	for (i = 0; i < group_info->ngroups; i++) {
188 		kgid = GROUP_AT(group_info, i);
189 		group = (u16)from_kgid_munged(user_ns, kgid);
190 		if (put_user(group, grouplist+i))
191 			return -EFAULT;
192 	}
193 
194 	return 0;
195 }
196 
197 static int groups16_from_user(struct group_info *group_info, u16 __user *grouplist)
198 {
199 	struct user_namespace *user_ns = current_user_ns();
200 	int i;
201 	u16 group;
202 	kgid_t kgid;
203 
204 	for (i = 0; i < group_info->ngroups; i++) {
205 		if (get_user(group, grouplist+i))
206 			return  -EFAULT;
207 
208 		kgid = make_kgid(user_ns, (gid_t)group);
209 		if (!gid_valid(kgid))
210 			return -EINVAL;
211 
212 		GROUP_AT(group_info, i) = kgid;
213 	}
214 
215 	return 0;
216 }
217 
218 asmlinkage long sys32_getgroups16(int gidsetsize, u16 __user *grouplist)
219 {
220 	const struct cred *cred = current_cred();
221 	int i;
222 
223 	if (gidsetsize < 0)
224 		return -EINVAL;
225 
226 	get_group_info(cred->group_info);
227 	i = cred->group_info->ngroups;
228 	if (gidsetsize) {
229 		if (i > gidsetsize) {
230 			i = -EINVAL;
231 			goto out;
232 		}
233 		if (groups16_to_user(grouplist, cred->group_info)) {
234 			i = -EFAULT;
235 			goto out;
236 		}
237 	}
238 out:
239 	put_group_info(cred->group_info);
240 	return i;
241 }
242 
243 asmlinkage long sys32_setgroups16(int gidsetsize, u16 __user *grouplist)
244 {
245 	struct group_info *group_info;
246 	int retval;
247 
248 	if (!capable(CAP_SETGID))
249 		return -EPERM;
250 	if ((unsigned)gidsetsize > NGROUPS_MAX)
251 		return -EINVAL;
252 
253 	group_info = groups_alloc(gidsetsize);
254 	if (!group_info)
255 		return -ENOMEM;
256 	retval = groups16_from_user(group_info, grouplist);
257 	if (retval) {
258 		put_group_info(group_info);
259 		return retval;
260 	}
261 
262 	retval = set_current_groups(group_info);
263 	put_group_info(group_info);
264 
265 	return retval;
266 }
267 
268 asmlinkage long sys32_getuid16(void)
269 {
270 	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
271 }
272 
273 asmlinkage long sys32_geteuid16(void)
274 {
275 	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
276 }
277 
278 asmlinkage long sys32_getgid16(void)
279 {
280 	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
281 }
282 
283 asmlinkage long sys32_getegid16(void)
284 {
285 	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
286 }
287 
288 #ifdef CONFIG_SYSVIPC
289 COMPAT_SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, unsigned long, second,
290 		unsigned long, third, compat_uptr_t, ptr)
291 {
292 	if (call >> 16)		/* hack for backward compatibility */
293 		return -EINVAL;
294 	return compat_sys_ipc(call, first, second, third, ptr, third);
295 }
296 #endif
297 
298 asmlinkage long sys32_truncate64(const char __user * path, unsigned long high, unsigned long low)
299 {
300 	if ((int)high < 0)
301 		return -EINVAL;
302 	else
303 		return sys_truncate(path, (high << 32) | low);
304 }
305 
306 asmlinkage long sys32_ftruncate64(unsigned int fd, unsigned long high, unsigned long low)
307 {
308 	if ((int)high < 0)
309 		return -EINVAL;
310 	else
311 		return sys_ftruncate(fd, (high << 32) | low);
312 }
313 
314 asmlinkage long sys32_pread64(unsigned int fd, char __user *ubuf,
315 				size_t count, u32 poshi, u32 poslo)
316 {
317 	if ((compat_ssize_t) count < 0)
318 		return -EINVAL;
319 	return sys_pread64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
320 }
321 
322 asmlinkage long sys32_pwrite64(unsigned int fd, const char __user *ubuf,
323 				size_t count, u32 poshi, u32 poslo)
324 {
325 	if ((compat_ssize_t) count < 0)
326 		return -EINVAL;
327 	return sys_pwrite64(fd, ubuf, count, ((loff_t)AA(poshi) << 32) | AA(poslo));
328 }
329 
330 asmlinkage compat_ssize_t sys32_readahead(int fd, u32 offhi, u32 offlo, s32 count)
331 {
332 	return sys_readahead(fd, ((loff_t)AA(offhi) << 32) | AA(offlo), count);
333 }
334 
335 struct stat64_emu31 {
336 	unsigned long long  st_dev;
337 	unsigned int    __pad1;
338 #define STAT64_HAS_BROKEN_ST_INO        1
339 	u32             __st_ino;
340 	unsigned int    st_mode;
341 	unsigned int    st_nlink;
342 	u32             st_uid;
343 	u32             st_gid;
344 	unsigned long long  st_rdev;
345 	unsigned int    __pad3;
346 	long            st_size;
347 	u32             st_blksize;
348 	unsigned char   __pad4[4];
349 	u32             __pad5;     /* future possible st_blocks high bits */
350 	u32             st_blocks;  /* Number 512-byte blocks allocated. */
351 	u32             st_atime;
352 	u32             __pad6;
353 	u32             st_mtime;
354 	u32             __pad7;
355 	u32             st_ctime;
356 	u32             __pad8;     /* will be high 32 bits of ctime someday */
357 	unsigned long   st_ino;
358 };
359 
360 static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
361 {
362 	struct stat64_emu31 tmp;
363 
364 	memset(&tmp, 0, sizeof(tmp));
365 
366 	tmp.st_dev = huge_encode_dev(stat->dev);
367 	tmp.st_ino = stat->ino;
368 	tmp.__st_ino = (u32)stat->ino;
369 	tmp.st_mode = stat->mode;
370 	tmp.st_nlink = (unsigned int)stat->nlink;
371 	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
372 	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
373 	tmp.st_rdev = huge_encode_dev(stat->rdev);
374 	tmp.st_size = stat->size;
375 	tmp.st_blksize = (u32)stat->blksize;
376 	tmp.st_blocks = (u32)stat->blocks;
377 	tmp.st_atime = (u32)stat->atime.tv_sec;
378 	tmp.st_mtime = (u32)stat->mtime.tv_sec;
379 	tmp.st_ctime = (u32)stat->ctime.tv_sec;
380 
381 	return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
382 }
383 
384 asmlinkage long sys32_stat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
385 {
386 	struct kstat stat;
387 	int ret = vfs_stat(filename, &stat);
388 	if (!ret)
389 		ret = cp_stat64(statbuf, &stat);
390 	return ret;
391 }
392 
393 asmlinkage long sys32_lstat64(const char __user * filename, struct stat64_emu31 __user * statbuf)
394 {
395 	struct kstat stat;
396 	int ret = vfs_lstat(filename, &stat);
397 	if (!ret)
398 		ret = cp_stat64(statbuf, &stat);
399 	return ret;
400 }
401 
402 asmlinkage long sys32_fstat64(unsigned long fd, struct stat64_emu31 __user * statbuf)
403 {
404 	struct kstat stat;
405 	int ret = vfs_fstat(fd, &stat);
406 	if (!ret)
407 		ret = cp_stat64(statbuf, &stat);
408 	return ret;
409 }
410 
411 asmlinkage long sys32_fstatat64(unsigned int dfd, const char __user *filename,
412 				struct stat64_emu31 __user* statbuf, int flag)
413 {
414 	struct kstat stat;
415 	int error;
416 
417 	error = vfs_fstatat(dfd, filename, &stat, flag);
418 	if (error)
419 		return error;
420 	return cp_stat64(statbuf, &stat);
421 }
422 
423 /*
424  * Linux/i386 didn't use to be able to handle more than
425  * 4 system call parameters, so these system calls used a memory
426  * block for parameter passing..
427  */
428 
429 struct mmap_arg_struct_emu31 {
430 	compat_ulong_t addr;
431 	compat_ulong_t len;
432 	compat_ulong_t prot;
433 	compat_ulong_t flags;
434 	compat_ulong_t fd;
435 	compat_ulong_t offset;
436 };
437 
438 asmlinkage unsigned long old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
439 {
440 	struct mmap_arg_struct_emu31 a;
441 
442 	if (copy_from_user(&a, arg, sizeof(a)))
443 		return -EFAULT;
444 	if (a.offset & ~PAGE_MASK)
445 		return -EINVAL;
446 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
447 			      a.offset >> PAGE_SHIFT);
448 }
449 
450 asmlinkage long sys32_mmap2(struct mmap_arg_struct_emu31 __user *arg)
451 {
452 	struct mmap_arg_struct_emu31 a;
453 
454 	if (copy_from_user(&a, arg, sizeof(a)))
455 		return -EFAULT;
456 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
457 }
458 
459 asmlinkage long sys32_read(unsigned int fd, char __user * buf, size_t count)
460 {
461 	if ((compat_ssize_t) count < 0)
462 		return -EINVAL;
463 
464 	return sys_read(fd, buf, count);
465 }
466 
467 asmlinkage long sys32_write(unsigned int fd, const char __user * buf, size_t count)
468 {
469 	if ((compat_ssize_t) count < 0)
470 		return -EINVAL;
471 
472 	return sys_write(fd, buf, count);
473 }
474 
475 /*
476  * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
477  * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
478  * because the 31 bit values differ from the 64 bit values.
479  */
480 
481 asmlinkage long
482 sys32_fadvise64(int fd, loff_t offset, size_t len, int advise)
483 {
484 	if (advise == 4)
485 		advise = POSIX_FADV_DONTNEED;
486 	else if (advise == 5)
487 		advise = POSIX_FADV_NOREUSE;
488 	return sys_fadvise64(fd, offset, len, advise);
489 }
490 
491 struct fadvise64_64_args {
492 	int fd;
493 	long long offset;
494 	long long len;
495 	int advice;
496 };
497 
498 asmlinkage long
499 sys32_fadvise64_64(struct fadvise64_64_args __user *args)
500 {
501 	struct fadvise64_64_args a;
502 
503 	if ( copy_from_user(&a, args, sizeof(a)) )
504 		return -EFAULT;
505 	if (a.advice == 4)
506 		a.advice = POSIX_FADV_DONTNEED;
507 	else if (a.advice == 5)
508 		a.advice = POSIX_FADV_NOREUSE;
509 	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
510 }
511