1/*
2 *	Wrapper functions for 16bit uid back compatibility. All nicely tied
3 *	together in the faint hope we can take the out in five years time.
4 */
5
6#include <linux/mm.h>
7#include <linux/utsname.h>
8#include <linux/mman.h>
9#include <linux/notifier.h>
10#include <linux/reboot.h>
11#include <linux/prctl.h>
12#include <linux/capability.h>
13#include <linux/init.h>
14#include <linux/highuid.h>
15#include <linux/security.h>
16#include <linux/syscalls.h>
17
18#include <asm/uaccess.h>
19
20asmlinkage long sys_chown16(const char __user * filename, old_uid_t user, old_gid_t group)
21{
22	long ret = sys_chown(filename, low2highuid(user), low2highgid(group));
23	/* avoid REGPARM breakage on x86: */
24	prevent_tail_call(ret);
25	return ret;
26}
27
28asmlinkage long sys_lchown16(const char __user * filename, old_uid_t user, old_gid_t group)
29{
30	long ret = sys_lchown(filename, low2highuid(user), low2highgid(group));
31	/* avoid REGPARM breakage on x86: */
32	prevent_tail_call(ret);
33	return ret;
34}
35
36asmlinkage long sys_fchown16(unsigned int fd, old_uid_t user, old_gid_t group)
37{
38	long ret = sys_fchown(fd, low2highuid(user), low2highgid(group));
39	/* avoid REGPARM breakage on x86: */
40	prevent_tail_call(ret);
41	return ret;
42}
43
44asmlinkage long sys_setregid16(old_gid_t rgid, old_gid_t egid)
45{
46	long ret = sys_setregid(low2highgid(rgid), low2highgid(egid));
47	/* avoid REGPARM breakage on x86: */
48	prevent_tail_call(ret);
49	return ret;
50}
51
52asmlinkage long sys_setgid16(old_gid_t gid)
53{
54	long ret = sys_setgid(low2highgid(gid));
55	/* avoid REGPARM breakage on x86: */
56	prevent_tail_call(ret);
57	return ret;
58}
59
60asmlinkage long sys_setreuid16(old_uid_t ruid, old_uid_t euid)
61{
62	long ret = sys_setreuid(low2highuid(ruid), low2highuid(euid));
63	/* avoid REGPARM breakage on x86: */
64	prevent_tail_call(ret);
65	return ret;
66}
67
68asmlinkage long sys_setuid16(old_uid_t uid)
69{
70	long ret = sys_setuid(low2highuid(uid));
71	/* avoid REGPARM breakage on x86: */
72	prevent_tail_call(ret);
73	return ret;
74}
75
76asmlinkage long sys_setresuid16(old_uid_t ruid, old_uid_t euid, old_uid_t suid)
77{
78	long ret = sys_setresuid(low2highuid(ruid), low2highuid(euid),
79				 low2highuid(suid));
80	/* avoid REGPARM breakage on x86: */
81	prevent_tail_call(ret);
82	return ret;
83}
84
85asmlinkage long sys_getresuid16(old_uid_t __user *ruid, old_uid_t __user *euid, old_uid_t __user *suid)
86{
87	int retval;
88
89	if (!(retval = put_user(high2lowuid(current->uid), ruid)) &&
90	    !(retval = put_user(high2lowuid(current->euid), euid)))
91		retval = put_user(high2lowuid(current->suid), suid);
92
93	return retval;
94}
95
96asmlinkage long sys_setresgid16(old_gid_t rgid, old_gid_t egid, old_gid_t sgid)
97{
98	long ret = sys_setresgid(low2highgid(rgid), low2highgid(egid),
99				 low2highgid(sgid));
100	/* avoid REGPARM breakage on x86: */
101	prevent_tail_call(ret);
102	return ret;
103}
104
105asmlinkage long sys_getresgid16(old_gid_t __user *rgid, old_gid_t __user *egid, old_gid_t __user *sgid)
106{
107	int retval;
108
109	if (!(retval = put_user(high2lowgid(current->gid), rgid)) &&
110	    !(retval = put_user(high2lowgid(current->egid), egid)))
111		retval = put_user(high2lowgid(current->sgid), sgid);
112
113	return retval;
114}
115
116asmlinkage long sys_setfsuid16(old_uid_t uid)
117{
118	long ret = sys_setfsuid(low2highuid(uid));
119	/* avoid REGPARM breakage on x86: */
120	prevent_tail_call(ret);
121	return ret;
122}
123
124asmlinkage long sys_setfsgid16(old_gid_t gid)
125{
126	long ret = sys_setfsgid(low2highgid(gid));
127	/* avoid REGPARM breakage on x86: */
128	prevent_tail_call(ret);
129	return ret;
130}
131
132static int groups16_to_user(old_gid_t __user *grouplist,
133    struct group_info *group_info)
134{
135	int i;
136	old_gid_t group;
137
138	for (i = 0; i < group_info->ngroups; i++) {
139		group = high2lowgid(GROUP_AT(group_info, i));
140		if (put_user(group, grouplist+i))
141			return -EFAULT;
142	}
143
144	return 0;
145}
146
147static int groups16_from_user(struct group_info *group_info,
148    old_gid_t __user *grouplist)
149{
150	int i;
151	old_gid_t group;
152
153	for (i = 0; i < group_info->ngroups; i++) {
154		if (get_user(group, grouplist+i))
155			return  -EFAULT;
156		GROUP_AT(group_info, i) = low2highgid(group);
157	}
158
159	return 0;
160}
161
162asmlinkage long sys_getgroups16(int gidsetsize, old_gid_t __user *grouplist)
163{
164	int i = 0;
165
166	if (gidsetsize < 0)
167		return -EINVAL;
168
169	get_group_info(current->group_info);
170	i = current->group_info->ngroups;
171	if (gidsetsize) {
172		if (i > gidsetsize) {
173			i = -EINVAL;
174			goto out;
175		}
176		if (groups16_to_user(grouplist, current->group_info)) {
177			i = -EFAULT;
178			goto out;
179		}
180	}
181out:
182	put_group_info(current->group_info);
183	return i;
184}
185
186asmlinkage long sys_setgroups16(int gidsetsize, old_gid_t __user *grouplist)
187{
188	struct group_info *group_info;
189	int retval;
190
191	if (!capable(CAP_SETGID))
192		return -EPERM;
193	if ((unsigned)gidsetsize > NGROUPS_MAX)
194		return -EINVAL;
195
196	group_info = groups_alloc(gidsetsize);
197	if (!group_info)
198		return -ENOMEM;
199	retval = groups16_from_user(group_info, grouplist);
200	if (retval) {
201		put_group_info(group_info);
202		return retval;
203	}
204
205	retval = set_current_groups(group_info);
206	put_group_info(group_info);
207
208	return retval;
209}
210
211asmlinkage long sys_getuid16(void)
212{
213	return high2lowuid(current->uid);
214}
215
216asmlinkage long sys_geteuid16(void)
217{
218	return high2lowuid(current->euid);
219}
220
221asmlinkage long sys_getgid16(void)
222{
223	return high2lowgid(current->gid);
224}
225
226asmlinkage long sys_getegid16(void)
227{
228	return high2lowgid(current->egid);
229}
230