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> |
0437eb59 | 23 | |
98c0d07c CLG |
24 | static struct kmem_cache *nsproxy_cachep; |
25 | ||
0437eb59 | 26 | struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); |
ab516013 SH |
27 | |
28 | static inline void get_nsproxy(struct nsproxy *ns) | |
29 | { | |
30 | atomic_inc(&ns->count); | |
31 | } | |
32 | ||
33 | void get_task_namespaces(struct task_struct *tsk) | |
34 | { | |
35 | struct nsproxy *ns = tsk->nsproxy; | |
36 | if (ns) { | |
37 | get_nsproxy(ns); | |
38 | } | |
39 | } | |
40 | ||
41 | /* | |
42 | * creates a copy of "orig" with refcount 1. | |
ab516013 | 43 | */ |
e3222c4e | 44 | static inline struct nsproxy *clone_nsproxy(struct nsproxy *orig) |
ab516013 SH |
45 | { |
46 | struct nsproxy *ns; | |
47 | ||
98c0d07c CLG |
48 | ns = kmem_cache_alloc(nsproxy_cachep, GFP_KERNEL); |
49 | if (ns) { | |
50 | memcpy(ns, orig, sizeof(struct nsproxy)); | |
ab516013 | 51 | atomic_set(&ns->count, 1); |
98c0d07c | 52 | } |
ab516013 SH |
53 | return ns; |
54 | } | |
55 | ||
56 | /* | |
e3222c4e BP |
57 | * Create new nsproxy and all of its the associated namespaces. |
58 | * Return the newly created nsproxy. Do not attach this to the task, | |
59 | * leave it to the caller to do proper locking and attach it to task. | |
ab516013 | 60 | */ |
213dd266 EB |
61 | static struct nsproxy *create_new_namespaces(unsigned long flags, |
62 | struct task_struct *tsk, struct fs_struct *new_fs) | |
ab516013 | 63 | { |
e3222c4e | 64 | struct nsproxy *new_nsp; |
467e9f4b | 65 | int err; |
ab516013 | 66 | |
e3222c4e BP |
67 | new_nsp = clone_nsproxy(tsk->nsproxy); |
68 | if (!new_nsp) | |
69 | return ERR_PTR(-ENOMEM); | |
1651e14e | 70 | |
e3222c4e | 71 | new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, new_fs); |
467e9f4b CLG |
72 | if (IS_ERR(new_nsp->mnt_ns)) { |
73 | err = PTR_ERR(new_nsp->mnt_ns); | |
e3222c4e | 74 | goto out_ns; |
467e9f4b | 75 | } |
e3222c4e BP |
76 | |
77 | new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns); | |
467e9f4b CLG |
78 | if (IS_ERR(new_nsp->uts_ns)) { |
79 | err = PTR_ERR(new_nsp->uts_ns); | |
e3222c4e | 80 | goto out_uts; |
467e9f4b | 81 | } |
e3222c4e BP |
82 | |
83 | new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns); | |
467e9f4b CLG |
84 | if (IS_ERR(new_nsp->ipc_ns)) { |
85 | err = PTR_ERR(new_nsp->ipc_ns); | |
e3222c4e | 86 | goto out_ipc; |
467e9f4b | 87 | } |
e3222c4e BP |
88 | |
89 | new_nsp->pid_ns = copy_pid_ns(flags, tsk->nsproxy->pid_ns); | |
467e9f4b CLG |
90 | if (IS_ERR(new_nsp->pid_ns)) { |
91 | err = PTR_ERR(new_nsp->pid_ns); | |
e3222c4e | 92 | goto out_pid; |
467e9f4b | 93 | } |
e3222c4e | 94 | |
acce292c | 95 | new_nsp->user_ns = copy_user_ns(flags, tsk->nsproxy->user_ns); |
467e9f4b CLG |
96 | if (IS_ERR(new_nsp->user_ns)) { |
97 | err = PTR_ERR(new_nsp->user_ns); | |
acce292c | 98 | goto out_user; |
467e9f4b | 99 | } |
acce292c | 100 | |
e3222c4e BP |
101 | return new_nsp; |
102 | ||
acce292c CLG |
103 | out_user: |
104 | if (new_nsp->pid_ns) | |
105 | put_pid_ns(new_nsp->pid_ns); | |
e3222c4e BP |
106 | out_pid: |
107 | if (new_nsp->ipc_ns) | |
108 | put_ipc_ns(new_nsp->ipc_ns); | |
109 | out_ipc: | |
110 | if (new_nsp->uts_ns) | |
111 | put_uts_ns(new_nsp->uts_ns); | |
112 | out_uts: | |
113 | if (new_nsp->mnt_ns) | |
114 | put_mnt_ns(new_nsp->mnt_ns); | |
115 | out_ns: | |
98c0d07c | 116 | kmem_cache_free(nsproxy_cachep, new_nsp); |
467e9f4b | 117 | return ERR_PTR(err); |
ab516013 SH |
118 | } |
119 | ||
120 | /* | |
121 | * called from clone. This now handles copy for nsproxy and all | |
122 | * namespaces therein. | |
123 | */ | |
213dd266 | 124 | int copy_namespaces(unsigned long flags, struct task_struct *tsk) |
ab516013 SH |
125 | { |
126 | struct nsproxy *old_ns = tsk->nsproxy; | |
1651e14e SH |
127 | struct nsproxy *new_ns; |
128 | int err = 0; | |
ab516013 SH |
129 | |
130 | if (!old_ns) | |
131 | return 0; | |
132 | ||
133 | get_nsproxy(old_ns); | |
134 | ||
77ec739d | 135 | if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | CLONE_NEWUSER))) |
1651e14e SH |
136 | return 0; |
137 | ||
e3222c4e BP |
138 | if (!capable(CAP_SYS_ADMIN)) { |
139 | err = -EPERM; | |
1651e14e SH |
140 | goto out; |
141 | } | |
142 | ||
e3222c4e BP |
143 | new_ns = create_new_namespaces(flags, tsk, tsk->fs); |
144 | if (IS_ERR(new_ns)) { | |
145 | err = PTR_ERR(new_ns); | |
146 | goto out; | |
147 | } | |
9a575a92 | 148 | |
e3222c4e | 149 | tsk->nsproxy = new_ns; |
1651e14e | 150 | out: |
444f378b | 151 | put_nsproxy(old_ns); |
1651e14e | 152 | return err; |
ab516013 SH |
153 | } |
154 | ||
155 | void free_nsproxy(struct nsproxy *ns) | |
156 | { | |
9a575a92 CLG |
157 | if (ns->mnt_ns) |
158 | put_mnt_ns(ns->mnt_ns); | |
159 | if (ns->uts_ns) | |
160 | put_uts_ns(ns->uts_ns); | |
161 | if (ns->ipc_ns) | |
162 | put_ipc_ns(ns->ipc_ns); | |
163 | if (ns->pid_ns) | |
164 | put_pid_ns(ns->pid_ns); | |
acce292c CLG |
165 | if (ns->user_ns) |
166 | put_user_ns(ns->user_ns); | |
98c0d07c | 167 | kmem_cache_free(nsproxy_cachep, ns); |
ab516013 | 168 | } |
e3222c4e BP |
169 | |
170 | /* | |
171 | * Called from unshare. Unshare all the namespaces part of nsproxy. | |
4e71e474 | 172 | * On success, returns the new nsproxy. |
e3222c4e BP |
173 | */ |
174 | int unshare_nsproxy_namespaces(unsigned long unshare_flags, | |
175 | struct nsproxy **new_nsp, struct fs_struct *new_fs) | |
176 | { | |
e3222c4e BP |
177 | int err = 0; |
178 | ||
77ec739d SH |
179 | if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC | |
180 | CLONE_NEWUSER))) | |
e3222c4e BP |
181 | return 0; |
182 | ||
e3222c4e BP |
183 | if (!capable(CAP_SYS_ADMIN)) |
184 | return -EPERM; | |
185 | ||
e3222c4e BP |
186 | *new_nsp = create_new_namespaces(unshare_flags, current, |
187 | new_fs ? new_fs : current->fs); | |
4e71e474 | 188 | if (IS_ERR(*new_nsp)) |
e3222c4e | 189 | err = PTR_ERR(*new_nsp); |
e3222c4e BP |
190 | return err; |
191 | } | |
98c0d07c CLG |
192 | |
193 | static int __init nsproxy_cache_init(void) | |
194 | { | |
195 | nsproxy_cachep = kmem_cache_create("nsproxy", sizeof(struct nsproxy), | |
196 | 0, SLAB_PANIC, NULL, NULL); | |
197 | return 0; | |
198 | } | |
199 | ||
200 | module_init(nsproxy_cache_init); |