2 * Copyright (C) 2006 IBM Corporation
4 * Author: Serge Hallyn <serue@us.ibm.com>
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
11 * Jun 2006 - namespaces support
13 * Pavel Emelianov <xemul@openvz.org>
16 #include <linux/module.h>
17 #include <linux/version.h>
18 #include <linux/nsproxy.h>
19 #include <linux/init_task.h>
20 #include <linux/mnt_namespace.h>
21 #include <linux/utsname.h>
22 #include <linux/pid_namespace.h>
24 struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
26 static inline void get_nsproxy(struct nsproxy *ns)
28 atomic_inc(&ns->count);
31 void get_task_namespaces(struct task_struct *tsk)
33 struct nsproxy *ns = tsk->nsproxy;
40 * creates a copy of "orig" with refcount 1.
42 static inline struct nsproxy *clone_nsproxy(struct nsproxy *orig)
46 ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
48 atomic_set(&ns->count, 1);
53 * Create new nsproxy and all of its the associated namespaces.
54 * Return the newly created nsproxy. Do not attach this to the task,
55 * leave it to the caller to do proper locking and attach it to task.
57 static struct nsproxy *create_new_namespaces(int flags, struct task_struct *tsk,
58 struct fs_struct *new_fs)
60 struct nsproxy *new_nsp;
62 new_nsp = clone_nsproxy(tsk->nsproxy);
64 return ERR_PTR(-ENOMEM);
66 new_nsp->mnt_ns = copy_mnt_ns(flags, tsk->nsproxy->mnt_ns, new_fs);
67 if (IS_ERR(new_nsp->mnt_ns))
70 new_nsp->uts_ns = copy_utsname(flags, tsk->nsproxy->uts_ns);
71 if (IS_ERR(new_nsp->uts_ns))
74 new_nsp->ipc_ns = copy_ipcs(flags, tsk->nsproxy->ipc_ns);
75 if (IS_ERR(new_nsp->ipc_ns))
78 new_nsp->pid_ns = copy_pid_ns(flags, tsk->nsproxy->pid_ns);
79 if (IS_ERR(new_nsp->pid_ns))
82 new_nsp->user_ns = copy_user_ns(flags, tsk->nsproxy->user_ns);
83 if (IS_ERR(new_nsp->user_ns))
90 put_pid_ns(new_nsp->pid_ns);
93 put_ipc_ns(new_nsp->ipc_ns);
96 put_uts_ns(new_nsp->uts_ns);
99 put_mnt_ns(new_nsp->mnt_ns);
102 return ERR_PTR(-ENOMEM);
106 * called from clone. This now handles copy for nsproxy and all
107 * namespaces therein.
109 int copy_namespaces(int flags, struct task_struct *tsk)
111 struct nsproxy *old_ns = tsk->nsproxy;
112 struct nsproxy *new_ns;
120 if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
123 if (!capable(CAP_SYS_ADMIN)) {
128 new_ns = create_new_namespaces(flags, tsk, tsk->fs);
129 if (IS_ERR(new_ns)) {
130 err = PTR_ERR(new_ns);
134 tsk->nsproxy = new_ns;
140 void free_nsproxy(struct nsproxy *ns)
143 put_mnt_ns(ns->mnt_ns);
145 put_uts_ns(ns->uts_ns);
147 put_ipc_ns(ns->ipc_ns);
149 put_pid_ns(ns->pid_ns);
151 put_user_ns(ns->user_ns);
156 * Called from unshare. Unshare all the namespaces part of nsproxy.
157 * On success, returns the new nsproxy.
159 int unshare_nsproxy_namespaces(unsigned long unshare_flags,
160 struct nsproxy **new_nsp, struct fs_struct *new_fs)
164 if (!(unshare_flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
167 if (!capable(CAP_SYS_ADMIN))
170 *new_nsp = create_new_namespaces(unshare_flags, current,
171 new_fs ? new_fs : current->fs);
172 if (IS_ERR(*new_nsp))
173 err = PTR_ERR(*new_nsp);