projects/linux·blob v4.10 · refs

217 lines · 5.0 KiB

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/mman.h>
8#include <linux/notifier.h>
9#include <linux/reboot.h>
10#include <linux/prctl.h>
11#include <linux/capability.h>
12#include <linux/init.h>
13#include <linux/highuid.h>
14#include <linux/security.h>
15#include <linux/syscalls.h>
16
17#include <linux/uaccess.h>
18
19SYSCALL_DEFINE3(chown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
20{
21 return sys_chown(filename, low2highuid(user), low2highgid(group));
22}
23
24SYSCALL_DEFINE3(lchown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
25{
26 return sys_lchown(filename, low2highuid(user), low2highgid(group));
27}
28
29SYSCALL_DEFINE3(fchown16, unsigned int, fd, old_uid_t, user, old_gid_t, group)
30{
31 return sys_fchown(fd, low2highuid(user), low2highgid(group));
32}
33
34SYSCALL_DEFINE2(setregid16, old_gid_t, rgid, old_gid_t, egid)
35{
36 return sys_setregid(low2highgid(rgid), low2highgid(egid));
37}
38
39SYSCALL_DEFINE1(setgid16, old_gid_t, gid)
40{
41 return sys_setgid(low2highgid(gid));
42}
43
44SYSCALL_DEFINE2(setreuid16, old_uid_t, ruid, old_uid_t, euid)
45{
46 return sys_setreuid(low2highuid(ruid), low2highuid(euid));
47}
48
49SYSCALL_DEFINE1(setuid16, old_uid_t, uid)
50{
51 return sys_setuid(low2highuid(uid));
52}
53
54SYSCALL_DEFINE3(setresuid16, old_uid_t, ruid, old_uid_t, euid, old_uid_t, suid)
55{
56 return sys_setresuid(low2highuid(ruid), low2highuid(euid),
57 low2highuid(suid));
58}
59
60SYSCALL_DEFINE3(getresuid16, old_uid_t __user *, ruidp, old_uid_t __user *, euidp, old_uid_t __user *, suidp)
61{
62 const struct cred *cred = current_cred();
63 int retval;
64 old_uid_t ruid, euid, suid;
65
66 ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
67 euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
68 suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
69
70 if (!(retval = put_user(ruid, ruidp)) &&
71 !(retval = put_user(euid, euidp)))
72 retval = put_user(suid, suidp);
73
74 return retval;
75}
76
77SYSCALL_DEFINE3(setresgid16, old_gid_t, rgid, old_gid_t, egid, old_gid_t, sgid)
78{
79 return sys_setresgid(low2highgid(rgid), low2highgid(egid),
80 low2highgid(sgid));
81}
82
83
84SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgidp, old_gid_t __user *, egidp, old_gid_t __user *, sgidp)
85{
86 const struct cred *cred = current_cred();
87 int retval;
88 old_gid_t rgid, egid, sgid;
89
90 rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
91 egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
92 sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
93
94 if (!(retval = put_user(rgid, rgidp)) &&
95 !(retval = put_user(egid, egidp)))
96 retval = put_user(sgid, sgidp);
97
98 return retval;
99}
100
101SYSCALL_DEFINE1(setfsuid16, old_uid_t, uid)
102{
103 return sys_setfsuid(low2highuid(uid));
104}
105
106SYSCALL_DEFINE1(setfsgid16, old_gid_t, gid)
107{
108 return sys_setfsgid(low2highgid(gid));
109}
110
111static int groups16_to_user(old_gid_t __user *grouplist,
112 struct group_info *group_info)
113{
114 struct user_namespace *user_ns = current_user_ns();
115 int i;
116 old_gid_t group;
117 kgid_t kgid;
118
119 for (i = 0; i < group_info->ngroups; i++) {
120 kgid = group_info->gid[i];
121 group = high2lowgid(from_kgid_munged(user_ns, kgid));
122 if (put_user(group, grouplist+i))
123 return -EFAULT;
124 }
125
126 return 0;
127}
128
129static int groups16_from_user(struct group_info *group_info,
130 old_gid_t __user *grouplist)
131{
132 struct user_namespace *user_ns = current_user_ns();
133 int i;
134 old_gid_t group;
135 kgid_t kgid;
136
137 for (i = 0; i < group_info->ngroups; i++) {
138 if (get_user(group, grouplist+i))
139 return -EFAULT;
140
141 kgid = make_kgid(user_ns, low2highgid(group));
142 if (!gid_valid(kgid))
143 return -EINVAL;
144
145 group_info->gid[i] = kgid;
146 }
147
148 return 0;
149}
150
151SYSCALL_DEFINE2(getgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
152{
153 const struct cred *cred = current_cred();
154 int i;
155
156 if (gidsetsize < 0)
157 return -EINVAL;
158
159 i = cred->group_info->ngroups;
160 if (gidsetsize) {
161 if (i > gidsetsize) {
162 i = -EINVAL;
163 goto out;
164 }
165 if (groups16_to_user(grouplist, cred->group_info)) {
166 i = -EFAULT;
167 goto out;
168 }
169 }
170out:
171 return i;
172}
173
174SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
175{
176 struct group_info *group_info;
177 int retval;
178
179 if (!may_setgroups())
180 return -EPERM;
181 if ((unsigned)gidsetsize > NGROUPS_MAX)
182 return -EINVAL;
183
184 group_info = groups_alloc(gidsetsize);
185 if (!group_info)
186 return -ENOMEM;
187 retval = groups16_from_user(group_info, grouplist);
188 if (retval) {
189 put_group_info(group_info);
190 return retval;
191 }
192
193 retval = set_current_groups(group_info);
194 put_group_info(group_info);
195
196 return retval;
197}
198
199SYSCALL_DEFINE0(getuid16)
200{
201 return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
202}
203
204SYSCALL_DEFINE0(geteuid16)
205{
206 return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
207}
208
209SYSCALL_DEFINE0(getgid16)
210{
211 return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
212}
213
214SYSCALL_DEFINE0(getegid16)
215{
216 return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
217}