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  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *	Wrapper functions for 16bit uid back compatibility. All nicely tied
  4 *	together in the faint hope we can take the out in five years time.
  5 */
  6
  7#include <linux/mm.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/cred.h>
 17#include <linux/syscalls.h>
 18
 19#include <linux/uaccess.h>
 20
 21#include "uid16.h"
 22
 23SYSCALL_DEFINE3(chown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 24{
 25	return ksys_chown(filename, low2highuid(user), low2highgid(group));
 26}
 27
 28SYSCALL_DEFINE3(lchown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 29{
 30	return ksys_lchown(filename, low2highuid(user), low2highgid(group));
 31}
 32
 33SYSCALL_DEFINE3(fchown16, unsigned int, fd, old_uid_t, user, old_gid_t, group)
 34{
 35	return ksys_fchown(fd, low2highuid(user), low2highgid(group));
 36}
 37
 38SYSCALL_DEFINE2(setregid16, old_gid_t, rgid, old_gid_t, egid)
 39{
 40	return __sys_setregid(low2highgid(rgid), low2highgid(egid));
 41}
 42
 43SYSCALL_DEFINE1(setgid16, old_gid_t, gid)
 44{
 45	return __sys_setgid(low2highgid(gid));
 46}
 47
 48SYSCALL_DEFINE2(setreuid16, old_uid_t, ruid, old_uid_t, euid)
 49{
 50	return __sys_setreuid(low2highuid(ruid), low2highuid(euid));
 51}
 52
 53SYSCALL_DEFINE1(setuid16, old_uid_t, uid)
 54{
 55	return __sys_setuid(low2highuid(uid));
 56}
 57
 58SYSCALL_DEFINE3(setresuid16, old_uid_t, ruid, old_uid_t, euid, old_uid_t, suid)
 59{
 60	return __sys_setresuid(low2highuid(ruid), low2highuid(euid),
 61				 low2highuid(suid));
 62}
 63
 64SYSCALL_DEFINE3(getresuid16, old_uid_t __user *, ruidp, old_uid_t __user *, euidp, old_uid_t __user *, suidp)
 65{
 66	const struct cred *cred = current_cred();
 67	int retval;
 68	old_uid_t ruid, euid, suid;
 69
 70	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
 71	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
 72	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
 73
 74	if (!(retval   = put_user(ruid, ruidp)) &&
 75	    !(retval   = put_user(euid, euidp)))
 76		retval = put_user(suid, suidp);
 77
 78	return retval;
 79}
 80
 81SYSCALL_DEFINE3(setresgid16, old_gid_t, rgid, old_gid_t, egid, old_gid_t, sgid)
 82{
 83	return __sys_setresgid(low2highgid(rgid), low2highgid(egid),
 84				 low2highgid(sgid));
 85}
 86
 87SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgidp, old_gid_t __user *, egidp, old_gid_t __user *, sgidp)
 88{
 89	const struct cred *cred = current_cred();
 90	int retval;
 91	old_gid_t rgid, egid, sgid;
 92
 93	rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
 94	egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
 95	sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
 96
 97	if (!(retval   = put_user(rgid, rgidp)) &&
 98	    !(retval   = put_user(egid, egidp)))
 99		retval = put_user(sgid, sgidp);
100
101	return retval;
102}
103
104SYSCALL_DEFINE1(setfsuid16, old_uid_t, uid)
105{
106	return __sys_setfsuid(low2highuid(uid));
107}
108
109SYSCALL_DEFINE1(setfsgid16, old_gid_t, gid)
110{
111	return __sys_setfsgid(low2highgid(gid));
112}
113
114static int groups16_to_user(old_gid_t __user *grouplist,
115    struct group_info *group_info)
116{
117	struct user_namespace *user_ns = current_user_ns();
118	int i;
119	old_gid_t group;
120	kgid_t kgid;
121
122	for (i = 0; i < group_info->ngroups; i++) {
123		kgid = group_info->gid[i];
124		group = high2lowgid(from_kgid_munged(user_ns, kgid));
125		if (put_user(group, grouplist+i))
126			return -EFAULT;
127	}
128
129	return 0;
130}
131
132static int groups16_from_user(struct group_info *group_info,
133    old_gid_t __user *grouplist)
134{
135	struct user_namespace *user_ns = current_user_ns();
136	int i;
137	old_gid_t group;
138	kgid_t kgid;
139
140	for (i = 0; i < group_info->ngroups; i++) {
141		if (get_user(group, grouplist+i))
142			return  -EFAULT;
143
144		kgid = make_kgid(user_ns, low2highgid(group));
145		if (!gid_valid(kgid))
146			return -EINVAL;
147
148		group_info->gid[i] = kgid;
149	}
150
151	return 0;
152}
153
154SYSCALL_DEFINE2(getgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
155{
156	const struct cred *cred = current_cred();
157	int i;
158
159	if (gidsetsize < 0)
160		return -EINVAL;
161
162	i = cred->group_info->ngroups;
163	if (gidsetsize) {
164		if (i > gidsetsize) {
165			i = -EINVAL;
166			goto out;
167		}
168		if (groups16_to_user(grouplist, cred->group_info)) {
169			i = -EFAULT;
170			goto out;
171		}
172	}
173out:
174	return i;
175}
176
177SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
178{
179	struct group_info *group_info;
180	int retval;
181
182	if (!may_setgroups())
183		return -EPERM;
184	if ((unsigned)gidsetsize > NGROUPS_MAX)
185		return -EINVAL;
186
187	group_info = groups_alloc(gidsetsize);
188	if (!group_info)
189		return -ENOMEM;
190	retval = groups16_from_user(group_info, grouplist);
191	if (retval) {
192		put_group_info(group_info);
193		return retval;
194	}
195
196	groups_sort(group_info);
197	retval = set_current_groups(group_info);
198	put_group_info(group_info);
199
200	return retval;
201}
202
203SYSCALL_DEFINE0(getuid16)
204{
205	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
206}
207
208SYSCALL_DEFINE0(geteuid16)
209{
210	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
211}
212
213SYSCALL_DEFINE0(getgid16)
214{
215	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
216}
217
218SYSCALL_DEFINE0(getegid16)
219{
220	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
221}
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *	Wrapper functions for 16bit uid back compatibility. All nicely tied
  4 *	together in the faint hope we can take the out in five years time.
  5 */
  6
  7#include <linux/mm.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/cred.h>
 17#include <linux/syscalls.h>
 18
 19#include <linux/uaccess.h>
 20
 21#include "uid16.h"
 22
 23SYSCALL_DEFINE3(chown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 24{
 25	return ksys_chown(filename, low2highuid(user), low2highgid(group));
 26}
 27
 28SYSCALL_DEFINE3(lchown16, const char __user *, filename, old_uid_t, user, old_gid_t, group)
 29{
 30	return ksys_lchown(filename, low2highuid(user), low2highgid(group));
 31}
 32
 33SYSCALL_DEFINE3(fchown16, unsigned int, fd, old_uid_t, user, old_gid_t, group)
 34{
 35	return ksys_fchown(fd, low2highuid(user), low2highgid(group));
 36}
 37
 38SYSCALL_DEFINE2(setregid16, old_gid_t, rgid, old_gid_t, egid)
 39{
 40	return __sys_setregid(low2highgid(rgid), low2highgid(egid));
 41}
 42
 43SYSCALL_DEFINE1(setgid16, old_gid_t, gid)
 44{
 45	return __sys_setgid(low2highgid(gid));
 46}
 47
 48SYSCALL_DEFINE2(setreuid16, old_uid_t, ruid, old_uid_t, euid)
 49{
 50	return __sys_setreuid(low2highuid(ruid), low2highuid(euid));
 51}
 52
 53SYSCALL_DEFINE1(setuid16, old_uid_t, uid)
 54{
 55	return __sys_setuid(low2highuid(uid));
 56}
 57
 58SYSCALL_DEFINE3(setresuid16, old_uid_t, ruid, old_uid_t, euid, old_uid_t, suid)
 59{
 60	return __sys_setresuid(low2highuid(ruid), low2highuid(euid),
 61				 low2highuid(suid));
 62}
 63
 64SYSCALL_DEFINE3(getresuid16, old_uid_t __user *, ruidp, old_uid_t __user *, euidp, old_uid_t __user *, suidp)
 65{
 66	const struct cred *cred = current_cred();
 67	int retval;
 68	old_uid_t ruid, euid, suid;
 69
 70	ruid = high2lowuid(from_kuid_munged(cred->user_ns, cred->uid));
 71	euid = high2lowuid(from_kuid_munged(cred->user_ns, cred->euid));
 72	suid = high2lowuid(from_kuid_munged(cred->user_ns, cred->suid));
 73
 74	if (!(retval   = put_user(ruid, ruidp)) &&
 75	    !(retval   = put_user(euid, euidp)))
 76		retval = put_user(suid, suidp);
 77
 78	return retval;
 79}
 80
 81SYSCALL_DEFINE3(setresgid16, old_gid_t, rgid, old_gid_t, egid, old_gid_t, sgid)
 82{
 83	return __sys_setresgid(low2highgid(rgid), low2highgid(egid),
 84				 low2highgid(sgid));
 85}
 86
 87SYSCALL_DEFINE3(getresgid16, old_gid_t __user *, rgidp, old_gid_t __user *, egidp, old_gid_t __user *, sgidp)
 88{
 89	const struct cred *cred = current_cred();
 90	int retval;
 91	old_gid_t rgid, egid, sgid;
 92
 93	rgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->gid));
 94	egid = high2lowgid(from_kgid_munged(cred->user_ns, cred->egid));
 95	sgid = high2lowgid(from_kgid_munged(cred->user_ns, cred->sgid));
 96
 97	if (!(retval   = put_user(rgid, rgidp)) &&
 98	    !(retval   = put_user(egid, egidp)))
 99		retval = put_user(sgid, sgidp);
100
101	return retval;
102}
103
104SYSCALL_DEFINE1(setfsuid16, old_uid_t, uid)
105{
106	return __sys_setfsuid(low2highuid(uid));
107}
108
109SYSCALL_DEFINE1(setfsgid16, old_gid_t, gid)
110{
111	return __sys_setfsgid(low2highgid(gid));
112}
113
114static int groups16_to_user(old_gid_t __user *grouplist,
115    struct group_info *group_info)
116{
117	struct user_namespace *user_ns = current_user_ns();
118	int i;
119	old_gid_t group;
120	kgid_t kgid;
121
122	for (i = 0; i < group_info->ngroups; i++) {
123		kgid = group_info->gid[i];
124		group = high2lowgid(from_kgid_munged(user_ns, kgid));
125		if (put_user(group, grouplist+i))
126			return -EFAULT;
127	}
128
129	return 0;
130}
131
132static int groups16_from_user(struct group_info *group_info,
133    old_gid_t __user *grouplist)
134{
135	struct user_namespace *user_ns = current_user_ns();
136	int i;
137	old_gid_t group;
138	kgid_t kgid;
139
140	for (i = 0; i < group_info->ngroups; i++) {
141		if (get_user(group, grouplist+i))
142			return  -EFAULT;
143
144		kgid = make_kgid(user_ns, low2highgid(group));
145		if (!gid_valid(kgid))
146			return -EINVAL;
147
148		group_info->gid[i] = kgid;
149	}
150
151	return 0;
152}
153
154SYSCALL_DEFINE2(getgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
155{
156	const struct cred *cred = current_cred();
157	int i;
158
159	if (gidsetsize < 0)
160		return -EINVAL;
161
162	i = cred->group_info->ngroups;
163	if (gidsetsize) {
164		if (i > gidsetsize) {
165			i = -EINVAL;
166			goto out;
167		}
168		if (groups16_to_user(grouplist, cred->group_info)) {
169			i = -EFAULT;
170			goto out;
171		}
172	}
173out:
174	return i;
175}
176
177SYSCALL_DEFINE2(setgroups16, int, gidsetsize, old_gid_t __user *, grouplist)
178{
179	struct group_info *group_info;
180	int retval;
181
182	if (!may_setgroups())
183		return -EPERM;
184	if ((unsigned)gidsetsize > NGROUPS_MAX)
185		return -EINVAL;
186
187	group_info = groups_alloc(gidsetsize);
188	if (!group_info)
189		return -ENOMEM;
190	retval = groups16_from_user(group_info, grouplist);
191	if (retval) {
192		put_group_info(group_info);
193		return retval;
194	}
195
196	groups_sort(group_info);
197	retval = set_current_groups(group_info);
198	put_group_info(group_info);
199
200	return retval;
201}
202
203SYSCALL_DEFINE0(getuid16)
204{
205	return high2lowuid(from_kuid_munged(current_user_ns(), current_uid()));
206}
207
208SYSCALL_DEFINE0(geteuid16)
209{
210	return high2lowuid(from_kuid_munged(current_user_ns(), current_euid()));
211}
212
213SYSCALL_DEFINE0(getgid16)
214{
215	return high2lowgid(from_kgid_munged(current_user_ns(), current_gid()));
216}
217
218SYSCALL_DEFINE0(getegid16)
219{
220	return high2lowgid(from_kgid_munged(current_user_ns(), current_egid()));
221}