blob: 674aceb7335ad56f7a2a8ba2996d0faa4ed850db [file] [log] [blame]
Serge E. Hallynab516012006-10-02 02:18:06 -07001/*
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.
Kirill Korotaev25b21cb2006-10-02 02:18:19 -070010 *
11 * Jun 2006 - namespaces support
12 * OpenVZ, SWsoft Inc.
13 * Pavel Emelianov <xemul@openvz.org>
Serge E. Hallynab516012006-10-02 02:18:06 -070014 */
15
16#include <linux/module.h>
17#include <linux/version.h>
18#include <linux/nsproxy.h>
Serge E. Hallyn0437eb52006-10-02 02:18:07 -070019#include <linux/init_task.h>
Serge E. Hallyn1651e142006-10-02 02:18:08 -070020#include <linux/namespace.h>
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -070021#include <linux/utsname.h>
Serge E. Hallyn0437eb52006-10-02 02:18:07 -070022
23struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
Serge E. Hallynab516012006-10-02 02:18:06 -070024
25static inline void get_nsproxy(struct nsproxy *ns)
26{
27 atomic_inc(&ns->count);
28}
29
30void get_task_namespaces(struct task_struct *tsk)
31{
32 struct nsproxy *ns = tsk->nsproxy;
33 if (ns) {
34 get_nsproxy(ns);
35 }
36}
37
38/*
39 * creates a copy of "orig" with refcount 1.
40 * This does not grab references to the contained namespaces,
41 * so that needs to be done by dup_namespaces.
42 */
43static inline struct nsproxy *clone_namespaces(struct nsproxy *orig)
44{
45 struct nsproxy *ns;
46
Alexey Dobriyane05d7222006-10-19 23:29:12 -070047 ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
48 if (ns)
Serge E. Hallynab516012006-10-02 02:18:06 -070049 atomic_set(&ns->count, 1);
Serge E. Hallynab516012006-10-02 02:18:06 -070050 return ns;
51}
52
53/*
54 * copies the nsproxy, setting refcount to 1, and grabbing a
55 * reference to all contained namespaces. Called from
56 * sys_unshare()
57 */
58struct nsproxy *dup_namespaces(struct nsproxy *orig)
59{
60 struct nsproxy *ns = clone_namespaces(orig);
61
Serge E. Hallyn1651e142006-10-02 02:18:08 -070062 if (ns) {
63 if (ns->namespace)
64 get_namespace(ns->namespace);
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -070065 if (ns->uts_ns)
66 get_uts_ns(ns->uts_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -070067 if (ns->ipc_ns)
68 get_ipc_ns(ns->ipc_ns);
Serge E. Hallyn1651e142006-10-02 02:18:08 -070069 }
70
Serge E. Hallynab516012006-10-02 02:18:06 -070071 return ns;
72}
73
74/*
75 * called from clone. This now handles copy for nsproxy and all
76 * namespaces therein.
77 */
78int copy_namespaces(int flags, struct task_struct *tsk)
79{
80 struct nsproxy *old_ns = tsk->nsproxy;
Serge E. Hallyn1651e142006-10-02 02:18:08 -070081 struct nsproxy *new_ns;
82 int err = 0;
Serge E. Hallynab516012006-10-02 02:18:06 -070083
84 if (!old_ns)
85 return 0;
86
87 get_nsproxy(old_ns);
88
Kirill Korotaev25b21cb2006-10-02 02:18:19 -070089 if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
Serge E. Hallyn1651e142006-10-02 02:18:08 -070090 return 0;
91
92 new_ns = clone_namespaces(old_ns);
93 if (!new_ns) {
94 err = -ENOMEM;
95 goto out;
96 }
97
98 tsk->nsproxy = new_ns;
99
100 err = copy_namespace(flags, tsk);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700101 if (err)
102 goto out_ns;
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700103
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700104 err = copy_utsname(flags, tsk);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700105 if (err)
106 goto out_uts;
107
108 err = copy_ipcs(flags, tsk);
109 if (err)
110 goto out_ipc;
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700111
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700112out:
113 put_nsproxy(old_ns);
114 return err;
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700115
116out_ipc:
117 if (new_ns->uts_ns)
118 put_uts_ns(new_ns->uts_ns);
119out_uts:
120 if (new_ns->namespace)
121 put_namespace(new_ns->namespace);
122out_ns:
123 tsk->nsproxy = old_ns;
Pavel5d124e92006-10-02 02:18:24 -0700124 kfree(new_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700125 goto out;
Serge E. Hallynab516012006-10-02 02:18:06 -0700126}
127
128void free_nsproxy(struct nsproxy *ns)
129{
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700130 if (ns->namespace)
131 put_namespace(ns->namespace);
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700132 if (ns->uts_ns)
133 put_uts_ns(ns->uts_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700134 if (ns->ipc_ns)
135 put_ipc_ns(ns->ipc_ns);
Serge E. Hallynab516012006-10-02 02:18:06 -0700136 kfree(ns);
137}