Commit | Line | Data |
---|---|---|
ab516013 SH |
1 | /* |
2 | * Copyright (C) 2006 IBM Corporation | |
3 | * | |
4 | * Author: Serge Hallyn <serue@us.ibm.com> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License as | |
8 | * published by the Free Software Foundation, version 2 of the | |
9 | * License. | |
25b21cb2 KK |
10 | * |
11 | * Jun 2006 - namespaces support | |
12 | * OpenVZ, SWsoft Inc. | |
13 | * Pavel Emelianov <xemul@openvz.org> | |
ab516013 SH |
14 | */ |
15 | ||
16 | #include <linux/module.h> | |
17 | #include <linux/version.h> | |
18 | #include <linux/nsproxy.h> | |
0437eb59 | 19 | #include <linux/init_task.h> |
6b3286ed | 20 | #include <linux/mnt_namespace.h> |
4865ecf1 | 21 | #include <linux/utsname.h> |
9a575a92 | 22 | #include <linux/pid_namespace.h> |
9dd776b6 | 23 | #include <net/net_namespace.h> |
0437eb59 | 24 | |
98c0d07c CLG |
25 | static struct kmem_cache *nsproxy_cachep; |
26 | ||
0437eb59 | 27 | struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); |
ab516013 | 28 | |
ab516013 SH |
29 | /* |
30 | * creates a copy of "orig" with refcount 1. | |
ab516013 | 31 | */ |
e3222c4e | 32 | static inline struct nsproxy *clone_nsproxy(struct nsproxy *orig) |
ab516013 SH |
33 | { |
34 | struct nsproxy *ns; | |
35 | ||
98c0d07c CLG |
36 | ns = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL); |
37 | if (ns) { | |
38 | memcpy(ns, orig, sizeof(struct nsproxy)); | |
ab516013 | 39 | atomic_set(&ns->count, 1); |
98c0d07c | 40 | } |
ab516013 SH |
41 | return ns; |
42 | } | |
43 | ||
44 | /* | |
e3222c4e BP |
45 | * Create new nsproxy and all of its the associated namespaces. |
46 | * Return the newly created nsproxy. Do not attach this to the task, | |
47 | * leave it to the caller to do proper locking and attach it to task. | |
ab516013 | 48 | */ |
213dd266 EB |
49 | static struct nsproxy *create_new_namespaces(unsigned long flags, |
50 | struct task_struct *tsk, struct fs_struct *new_fs) | |
ab516013 | 51 | { |
e3222c4e | 52 | struct nsproxy *new_nsp; |
467e9f4b | 53 | int err; |
ab516013 | 54 | |
e3222c4e BP |
55 | new_nsp = clone_nsproxy(tsk->nsproxy); |
56 | if (!new_nsp) | |
57 | return ERR_PTR(-ENOMEM); | |
1651e14e | 58 | |
e3222c4e | 59 | new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, new_fs); |
467e9f4b CLG |
60 | if (IS_ERR(new_nsp->mnt_ns)) { |
61 | err = PTR_ERR(new_nsp->mnt_ns); | |
e3222c4e | 62 | goto out_ns; |
467e9f4b | 63 | } |
e3222c4e BP |
64 | |
65 | new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns); | |
467e9f4b CLG |
66 | if (IS_ERR(new_nsp->uts_ns)) { |
67 | err = PTR_ERR(new_nsp->uts_ns); | |
e3222c4e | 68 | goto out_uts; |
467e9f4b | 69 | } |
e3222c4e BP |
70 | |
71 | new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns); | |
467e9f4b CLG |
72 | if (IS_ERR(new_nsp->ipc_ns)) { |
73 | err = PTR_ERR(new_nsp->ipc_ns); | |
e3222c4e | 74 | goto out_ipc; |
467e9f4b | 75 | } |
e3222c4e | 76 | |
2894d650 | 77 | new_nsp->pid_ns = copy_pid_ns(flags, task_active_pid_ns(tsk)); |
467e9f4b CLG |
78 | if (IS_ERR(new_nsp->pid_ns)) { |
79 | err = PTR_ERR(new_nsp->pid_ns); | |
e3222c4e | 80 | goto out_pid; |
467e9f4b | 81 | } |
e3222c4e | 82 | |
acce292c | 83 | new_nsp->user_ns = copy_user_ns(flags, tsk->nsproxy->user_ns); |
467e9f4b CLG |
84 | if (IS_ERR(new_nsp->user_ns)) { |
85 | err = PTR_ERR(new_nsp->user_ns); | |
acce292c | 86 | goto out_user; |
467e9f4b | 87 | } |
acce292c | 88 | |
9dd776b6 EB |
89 | new_nsp->net_ns = copy_net_ns(flags, tsk->nsproxy->net_ns); |
90 | if (IS_ERR(new_nsp->net_ns)) { | |
91 | err = PTR_ERR(new_nsp->net_ns); | |
92 | goto out_net; | |
93 | } | |
94 | ||
e3222c4e BP |
95 | return new_nsp; |
96 | ||
9dd776b6 EB |
97 | out_net: |
98 | if (new_nsp->user_ns) | |
99 | put_user_ns(new_nsp->user_ns); | |
acce292c CLG |
100 | out_user: |
101 | if (new_nsp->pid_ns) | |
102 | put_pid_ns(new_nsp->pid_ns); | |
e3222c4e BP |
103 | out_pid: |
104 | if (new_nsp->ipc_ns) | |
105 | put_ipc_ns(new_nsp->ipc_ns); | |
106 | out_ipc: | |
107 | if (new_nsp->uts_ns) | |
108 | put_uts_ns(new_nsp->uts_ns); | |
109 | out_uts: | |
110 | if (new_nsp->mnt_ns) | |
111 | put_mnt_ns(new_nsp->mnt_ns); | |
112 | out_ns: | |
98c0d07c | 113 | kmem_cache_free(nsproxy_cachep, new_nsp); |
467e9f4b | 114 | return ERR_PTR(err); |
ab516013 SH |
115 | } |
116 | ||
117 | /* | |
118 | * called from clone. This now handles copy for nsproxy and all | |
119 | * namespaces therein. | |
120 | */ | |
213dd266 | 121 | int copy_namespaces(unsigned long flags, struct task_struct *tsk) |
ab516013 SH |
122 | { |
123 | struct nsproxy *old_ns = tsk->nsproxy; | |
1651e14e SH |
124 | struct nsproxy *new_ns; |
125 | int err = 0; | |
ab516013 SH |
126 | |
127 | if (!old_ns) | |
128 | return 0; | |
129 | ||
130 | get_nsproxy(old_ns); | |
131 | ||
9dd776b6 | 132 | if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | CLONE_NEWUSER | CLONE_NEWNET))) |
1651e14e SH |
133 | return 0; |
134 | ||
e3222c4e BP |
135 | if (!capable(CAP_SYS_ADMIN)) { |
136 | err = -EPERM; | |
1651e14e SH |
137 | goto out; |
138 | } | |
139 | ||
e3222c4e BP |
140 | new_ns = create_new_namespaces(flags, tsk, tsk->fs); |
141 | if (IS_ERR(new_ns)) { | |
142 | err = PTR_ERR(new_ns); | |
143 | goto out; | |
144 | } | |
9a575a92 | 145 | |
858d72ea SH |
146 | err = ns_cgroup_clone(tsk); |
147 | if (err) { | |
148 | put_nsproxy(new_ns); | |
149 | goto out; | |
150 | } | |
151 | ||
e3222c4e | 152 | tsk->nsproxy = new_ns; |
858d72ea | 153 | |
1651e14e | 154 | out: |
444f378b | 155 | put_nsproxy(old_ns); |
1651e14e | 156 | return err; |
ab516013 SH |
157 | } |
158 | ||
159 | void free_nsproxy(struct nsproxy *ns) | |
160 | { | |
9a575a92 CLG |
161 | if (ns->mnt_ns) |
162 | put_mnt_ns(ns->mnt_ns); | |
163 | if (ns->uts_ns) | |
164 | put_uts_ns(ns->uts_ns); | |
165 | if (ns->ipc_ns) | |
166 | put_ipc_ns(ns->ipc_ns); | |
167 | if (ns->pid_ns) | |
168 | put_pid_ns(ns->pid_ns); | |
acce292c CLG |
169 | if (ns->user_ns) |
170 | put_user_ns(ns->user_ns); | |
9dd776b6 | 171 | put_net(ns->net_ns); |
98c0d07c | 172 | kmem_cache_free(nsproxy_cachep, ns); |
ab516013 | 173 | } |
e3222c4e BP |
174 | |
175 | /* | |
176 | * Called from unshare. Unshare all the namespaces part of nsproxy. | |
4e71e474 | 177 | * On success, returns the new nsproxy. |
e3222c4e BP |
178 | */ |
179 | int unshare_nsproxy_namespaces(unsigned long unshare_flags, | |
180 | struct nsproxy **new_nsp, struct fs_struct *new_fs) | |
181 | { | |
e3222c4e BP |
182 | int err = 0; |
183 | ||
77ec739d | 184 | if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
9dd776b6 | 185 | CLONE_NEWUSER | CLONE_NEWNET))) |
e3222c4e BP |
186 | return 0; |
187 | ||
e3222c4e BP |
188 | if (!capable(CAP_SYS_ADMIN)) |
189 | return -EPERM; | |
190 | ||
e3222c4e BP |
191 | *new_nsp = create_new_namespaces(unshare_flags, current, |
192 | new_fs ? new_fs : current->fs); | |
858d72ea | 193 | if (IS_ERR(*new_nsp)) { |
e3222c4e | 194 | err = PTR_ERR(*new_nsp); |
858d72ea SH |
195 | goto out; |
196 | } | |
197 | ||
198 | err = ns_cgroup_clone(current); | |
199 | if (err) | |
200 | put_nsproxy(*new_nsp); | |
201 | ||
202 | out: | |
e3222c4e BP |
203 | return err; |
204 | } | |
98c0d07c | 205 | |
cf7b708c PE |
206 | void switch_task_namespaces(struct task_struct *p, struct nsproxy *new) |
207 | { | |
208 | struct nsproxy *ns; | |
209 | ||
210 | might_sleep(); | |
211 | ||
212 | ns = p->nsproxy; | |
213 | ||
214 | rcu_assign_pointer(p->nsproxy, new); | |
215 | ||
216 | if (ns && atomic_dec_and_test(&ns->count)) { | |
217 | /* | |
218 | * wait for others to get what they want from this nsproxy. | |
219 | * | |
220 | * cannot release this nsproxy via the call_rcu() since | |
221 | * put_mnt_ns() will want to sleep | |
222 | */ | |
223 | synchronize_rcu(); | |
224 | free_nsproxy(ns); | |
225 | } | |
226 | } | |
227 | ||
228 | void exit_task_namespaces(struct task_struct *p) | |
229 | { | |
230 | switch_task_namespaces(p, NULL); | |
231 | } | |
232 | ||
98c0d07c CLG |
233 | static int __init nsproxy_cache_init(void) |
234 | { | |
db8906da | 235 | nsproxy_cachep = KMEM_CACHE(nsproxy, SLAB_PANIC); |
98c0d07c CLG |
236 | return 0; |
237 | } | |
238 | ||
239 | module_init(nsproxy_cache_init); |