xref: /openbmc/linux/arch/s390/kernel/compat_linux.c (revision 206a81c1)
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 COMPAT_SYSCALL_DEFINE3(s390_chown16, const char __user *, filename,
90 		       u16, user, u16, group)
91 {
92 	return sys_chown(filename, low2highuid(user), low2highgid(group));
93 }
94 
95 COMPAT_SYSCALL_DEFINE3(s390_lchown16, const char __user *,
96 		       filename, u16, user, u16, group)
97 {
98 	return sys_lchown(filename, low2highuid(user), low2highgid(group));
99 }
100 
101 COMPAT_SYSCALL_DEFINE3(s390_fchown16, unsigned int, fd, u16, user, u16, group)
102 {
103 	return sys_fchown(fd, low2highuid(user), low2highgid(group));
104 }
105 
106 COMPAT_SYSCALL_DEFINE2(s390_setregid16, u16, rgid, u16, egid)
107 {
108 	return sys_setregid(low2highgid(rgid), low2highgid(egid));
109 }
110 
111 COMPAT_SYSCALL_DEFINE1(s390_setgid16, u16, gid)
112 {
113 	return sys_setgid((gid_t)gid);
114 }
115 
116 COMPAT_SYSCALL_DEFINE2(s390_setreuid16, u16, ruid, u16, euid)
117 {
118 	return sys_setreuid(low2highuid(ruid), low2highuid(euid));
119 }
120 
121 COMPAT_SYSCALL_DEFINE1(s390_setuid16, u16, uid)
122 {
123 	return sys_setuid((uid_t)uid);
124 }
125 
126 COMPAT_SYSCALL_DEFINE3(s390_setresuid16, u16, ruid, u16, euid, u16, suid)
127 {
128 	return sys_setresuid(low2highuid(ruid), low2highuid(euid),
129 			     low2highuid(suid));
130 }
131 
132 COMPAT_SYSCALL_DEFINE3(s390_getresuid16, u16 __user *, ruidp,
133 		       u16 __user *, euidp, u16 __user *, suidp)
134 {
135 	const struct cred *cred = current_cred();
136 	int retval;
137 	u16 ruid, euid, suid;
138 
139 	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
140 	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
141 	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
142 
143 	if (!(retval   = put_user(ruid, ruidp)) &&
144 	    !(retval   = put_user(euid, euidp)))
145 		retval = put_user(suid, suidp);
146 
147 	return retval;
148 }
149 
150 COMPAT_SYSCALL_DEFINE3(s390_setresgid16, u16, rgid, u16, egid, u16, sgid)
151 {
152 	return sys_setresgid(low2highgid(rgid), low2highgid(egid),
153 			     low2highgid(sgid));
154 }
155 
156 COMPAT_SYSCALL_DEFINE3(s390_getresgid16, u16 __user *, rgidp,
157 		       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 
174 COMPAT_SYSCALL_DEFINE1(s390_setfsuid16, u16, uid)
175 {
176 	return sys_setfsuid((uid_t)uid);
177 }
178 
179 COMPAT_SYSCALL_DEFINE1(s390_setfsgid16, u16, gid)
180 {
181 	return sys_setfsgid((gid_t)gid);
182 }
183 
184 static 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 
201 static 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 
222 COMPAT_SYSCALL_DEFINE2(s390_getgroups16, int, gidsetsize, u16 __user *, grouplist)
223 {
224 	const struct cred *cred = current_cred();
225 	int i;
226 
227 	if (gidsetsize < 0)
228 		return -EINVAL;
229 
230 	get_group_info(cred->group_info);
231 	i = cred->group_info->ngroups;
232 	if (gidsetsize) {
233 		if (i > gidsetsize) {
234 			i = -EINVAL;
235 			goto out;
236 		}
237 		if (groups16_to_user(grouplist, cred->group_info)) {
238 			i = -EFAULT;
239 			goto out;
240 		}
241 	}
242 out:
243 	put_group_info(cred->group_info);
244 	return i;
245 }
246 
247 COMPAT_SYSCALL_DEFINE2(s390_setgroups16, int, gidsetsize, u16 __user *, grouplist)
248 {
249 	struct group_info *group_info;
250 	int retval;
251 
252 	if (!capable(CAP_SETGID))
253 		return -EPERM;
254 	if ((unsigned)gidsetsize > NGROUPS_MAX)
255 		return -EINVAL;
256 
257 	group_info = groups_alloc(gidsetsize);
258 	if (!group_info)
259 		return -ENOMEM;
260 	retval = groups16_from_user(group_info, grouplist);
261 	if (retval) {
262 		put_group_info(group_info);
263 		return retval;
264 	}
265 
266 	retval = set_current_groups(group_info);
267 	put_group_info(group_info);
268 
269 	return retval;
270 }
271 
272 COMPAT_SYSCALL_DEFINE0(s390_getuid16)
273 {
274 	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
275 }
276 
277 COMPAT_SYSCALL_DEFINE0(s390_geteuid16)
278 {
279 	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
280 }
281 
282 COMPAT_SYSCALL_DEFINE0(s390_getgid16)
283 {
284 	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
285 }
286 
287 COMPAT_SYSCALL_DEFINE0(s390_getegid16)
288 {
289 	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
290 }
291 
292 #ifdef CONFIG_SYSVIPC
293 COMPAT_SYSCALL_DEFINE5(s390_ipc, uint, call, int, first, compat_ulong_t, second,
294 		compat_ulong_t, third, compat_uptr_t, ptr)
295 {
296 	if (call >> 16)		/* hack for backward compatibility */
297 		return -EINVAL;
298 	return compat_sys_ipc(call, first, second, third, ptr, third);
299 }
300 #endif
301 
302 COMPAT_SYSCALL_DEFINE3(s390_truncate64, const char __user *, path, u32, high, u32, low)
303 {
304 	return sys_truncate(path, (unsigned long)high << 32 | low);
305 }
306 
307 COMPAT_SYSCALL_DEFINE3(s390_ftruncate64, unsigned int, fd, u32, high, u32, low)
308 {
309 	return sys_ftruncate(fd, (unsigned long)high << 32 | low);
310 }
311 
312 COMPAT_SYSCALL_DEFINE5(s390_pread64, unsigned int, fd, char __user *, ubuf,
313 		       compat_size_t, count, u32, high, u32, low)
314 {
315 	if ((compat_ssize_t) count < 0)
316 		return -EINVAL;
317 	return sys_pread64(fd, ubuf, count, (unsigned long)high << 32 | low);
318 }
319 
320 COMPAT_SYSCALL_DEFINE5(s390_pwrite64, unsigned int, fd, const char __user *, ubuf,
321 		       compat_size_t, count, u32, high, u32, low)
322 {
323 	if ((compat_ssize_t) count < 0)
324 		return -EINVAL;
325 	return sys_pwrite64(fd, ubuf, count, (unsigned long)high << 32 | low);
326 }
327 
328 COMPAT_SYSCALL_DEFINE4(s390_readahead, int, fd, u32, high, u32, low, s32, count)
329 {
330 	return sys_readahead(fd, (unsigned long)high << 32 | low, count);
331 }
332 
333 struct stat64_emu31 {
334 	unsigned long long  st_dev;
335 	unsigned int    __pad1;
336 #define STAT64_HAS_BROKEN_ST_INO        1
337 	u32             __st_ino;
338 	unsigned int    st_mode;
339 	unsigned int    st_nlink;
340 	u32             st_uid;
341 	u32             st_gid;
342 	unsigned long long  st_rdev;
343 	unsigned int    __pad3;
344 	long            st_size;
345 	u32             st_blksize;
346 	unsigned char   __pad4[4];
347 	u32             __pad5;     /* future possible st_blocks high bits */
348 	u32             st_blocks;  /* Number 512-byte blocks allocated. */
349 	u32             st_atime;
350 	u32             __pad6;
351 	u32             st_mtime;
352 	u32             __pad7;
353 	u32             st_ctime;
354 	u32             __pad8;     /* will be high 32 bits of ctime someday */
355 	unsigned long   st_ino;
356 };
357 
358 static int cp_stat64(struct stat64_emu31 __user *ubuf, struct kstat *stat)
359 {
360 	struct stat64_emu31 tmp;
361 
362 	memset(&tmp, 0, sizeof(tmp));
363 
364 	tmp.st_dev = huge_encode_dev(stat->dev);
365 	tmp.st_ino = stat->ino;
366 	tmp.__st_ino = (u32)stat->ino;
367 	tmp.st_mode = stat->mode;
368 	tmp.st_nlink = (unsigned int)stat->nlink;
369 	tmp.st_uid = from_kuid_munged(current_user_ns(), stat->uid);
370 	tmp.st_gid = from_kgid_munged(current_user_ns(), stat->gid);
371 	tmp.st_rdev = huge_encode_dev(stat->rdev);
372 	tmp.st_size = stat->size;
373 	tmp.st_blksize = (u32)stat->blksize;
374 	tmp.st_blocks = (u32)stat->blocks;
375 	tmp.st_atime = (u32)stat->atime.tv_sec;
376 	tmp.st_mtime = (u32)stat->mtime.tv_sec;
377 	tmp.st_ctime = (u32)stat->ctime.tv_sec;
378 
379 	return copy_to_user(ubuf,&tmp,sizeof(tmp)) ? -EFAULT : 0;
380 }
381 
382 COMPAT_SYSCALL_DEFINE2(s390_stat64, const char __user *, filename, struct stat64_emu31 __user *, statbuf)
383 {
384 	struct kstat stat;
385 	int ret = vfs_stat(filename, &stat);
386 	if (!ret)
387 		ret = cp_stat64(statbuf, &stat);
388 	return ret;
389 }
390 
391 COMPAT_SYSCALL_DEFINE2(s390_lstat64, const char __user *, filename, struct stat64_emu31 __user *, statbuf)
392 {
393 	struct kstat stat;
394 	int ret = vfs_lstat(filename, &stat);
395 	if (!ret)
396 		ret = cp_stat64(statbuf, &stat);
397 	return ret;
398 }
399 
400 COMPAT_SYSCALL_DEFINE2(s390_fstat64, unsigned int, fd, struct stat64_emu31 __user *, statbuf)
401 {
402 	struct kstat stat;
403 	int ret = vfs_fstat(fd, &stat);
404 	if (!ret)
405 		ret = cp_stat64(statbuf, &stat);
406 	return ret;
407 }
408 
409 COMPAT_SYSCALL_DEFINE4(s390_fstatat64, unsigned int, dfd, const char __user *, filename,
410 		       struct stat64_emu31 __user *, statbuf, int, flag)
411 {
412 	struct kstat stat;
413 	int error;
414 
415 	error = vfs_fstatat(dfd, filename, &stat, flag);
416 	if (error)
417 		return error;
418 	return cp_stat64(statbuf, &stat);
419 }
420 
421 /*
422  * Linux/i386 didn't use to be able to handle more than
423  * 4 system call parameters, so these system calls used a memory
424  * block for parameter passing..
425  */
426 
427 struct mmap_arg_struct_emu31 {
428 	compat_ulong_t addr;
429 	compat_ulong_t len;
430 	compat_ulong_t prot;
431 	compat_ulong_t flags;
432 	compat_ulong_t fd;
433 	compat_ulong_t offset;
434 };
435 
436 COMPAT_SYSCALL_DEFINE1(s390_old_mmap, struct mmap_arg_struct_emu31 __user *, arg)
437 {
438 	struct mmap_arg_struct_emu31 a;
439 
440 	if (copy_from_user(&a, arg, sizeof(a)))
441 		return -EFAULT;
442 	if (a.offset & ~PAGE_MASK)
443 		return -EINVAL;
444 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
445 			      a.offset >> PAGE_SHIFT);
446 }
447 
448 COMPAT_SYSCALL_DEFINE1(s390_mmap2, struct mmap_arg_struct_emu31 __user *, arg)
449 {
450 	struct mmap_arg_struct_emu31 a;
451 
452 	if (copy_from_user(&a, arg, sizeof(a)))
453 		return -EFAULT;
454 	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
455 }
456 
457 COMPAT_SYSCALL_DEFINE3(s390_read, unsigned int, fd, char __user *, buf, compat_size_t, count)
458 {
459 	if ((compat_ssize_t) count < 0)
460 		return -EINVAL;
461 
462 	return sys_read(fd, buf, count);
463 }
464 
465 COMPAT_SYSCALL_DEFINE3(s390_write, unsigned int, fd, const char __user *, buf, compat_size_t, count)
466 {
467 	if ((compat_ssize_t) count < 0)
468 		return -EINVAL;
469 
470 	return sys_write(fd, buf, count);
471 }
472 
473 /*
474  * 31 bit emulation wrapper functions for sys_fadvise64/fadvise64_64.
475  * These need to rewrite the advise values for POSIX_FADV_{DONTNEED,NOREUSE}
476  * because the 31 bit values differ from the 64 bit values.
477  */
478 
479 COMPAT_SYSCALL_DEFINE5(s390_fadvise64, int, fd, u32, high, u32, low, compat_size_t, len, int, advise)
480 {
481 	if (advise == 4)
482 		advise = POSIX_FADV_DONTNEED;
483 	else if (advise == 5)
484 		advise = POSIX_FADV_NOREUSE;
485 	return sys_fadvise64(fd, (unsigned long)high << 32 | low, len, advise);
486 }
487 
488 struct fadvise64_64_args {
489 	int fd;
490 	long long offset;
491 	long long len;
492 	int advice;
493 };
494 
495 COMPAT_SYSCALL_DEFINE1(s390_fadvise64_64, struct fadvise64_64_args __user *, args)
496 {
497 	struct fadvise64_64_args a;
498 
499 	if ( copy_from_user(&a, args, sizeof(a)) )
500 		return -EFAULT;
501 	if (a.advice == 4)
502 		a.advice = POSIX_FADV_DONTNEED;
503 	else if (a.advice == 5)
504 		a.advice = POSIX_FADV_NOREUSE;
505 	return sys_fadvise64_64(a.fd, a.offset, a.len, a.advice);
506 }
507 
508 COMPAT_SYSCALL_DEFINE6(s390_sync_file_range, int, fd, u32, offhigh, u32, offlow,
509 		       u32, nhigh, u32, nlow, unsigned int, flags)
510 {
511 	return sys_sync_file_range(fd, ((loff_t)offhigh << 32) + offlow,
512 				   ((u64)nhigh << 32) + nlow, flags);
513 }
514 
515 COMPAT_SYSCALL_DEFINE6(s390_fallocate, int, fd, int, mode, u32, offhigh, u32, offlow,
516 		       u32, lenhigh, u32, lenlow)
517 {
518 	return sys_fallocate(fd, mode, ((loff_t)offhigh << 32) + offlow,
519 			     ((u64)lenhigh << 32) + lenlow);
520 }
521