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review.evervolv.com / android_kernel_htc_msm8960 / 4b51d66989218aad731a721b5b28c79bf5388c09 / . / kernel / nsproxy.c
blob: f5b9ee6f6bbb02733cef1e64fabe4dc521efc767 [file] [log] [blame]
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]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.
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]10 *
11 * Jun 2006 - namespaces support
12 * OpenVZ, SWsoft Inc.
13 * Pavel Emelianov <xemul@openvz.org>
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]14 */
15
16#include <linux/module.h>
17#include <linux/version.h>
18#include <linux/nsproxy.h>
Serge E. Hallyn0437eb52006-10-02 02:18:07 -0700[diff] [blame]19#include <linux/init_task.h>
Kirill Korotaev6b3286e2006-12-08 02:37:56 -0800[diff] [blame]20#include <linux/mnt_namespace.h>
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700[diff] [blame]21#include <linux/utsname.h>
Cedric Le Goater9a575a92006-12-08 02:37:59 -0800[diff] [blame]22#include <linux/pid_namespace.h>
Serge E. Hallyn0437eb52006-10-02 02:18:07 -0700[diff] [blame]23
24struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]25
26static inline void get_nsproxy(struct nsproxy *ns)
27{
28 atomic_inc(&ns->count);
29}
30
31void get_task_namespaces(struct task_struct *tsk)
32{
33 struct nsproxy *ns = tsk->nsproxy;
34 if (ns) {
35 get_nsproxy(ns);
36 }
37}
38
39/*
40 * creates a copy of "orig" with refcount 1.
41 * This does not grab references to the contained namespaces,
42 * so that needs to be done by dup_namespaces.
43 */
44static inline struct nsproxy *clone_namespaces(struct nsproxy *orig)
45{
46 struct nsproxy *ns;
47
Alexey Dobriyane05d7222006-10-19 23:29:12 -0700[diff] [blame]48 ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
Eric W. Biederman5f8442e2006-12-13 00:34:04 -0800[diff] [blame]49 if (ns)
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]50 atomic_set(&ns->count, 1);
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]51 return ns;
52}
53
54/*
55 * copies the nsproxy, setting refcount to 1, and grabbing a
56 * reference to all contained namespaces. Called from
57 * sys_unshare()
58 */
59struct nsproxy *dup_namespaces(struct nsproxy *orig)
60{
61 struct nsproxy *ns = clone_namespaces(orig);
62
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]63 if (ns) {
Kirill Korotaev6b3286e2006-12-08 02:37:56 -0800[diff] [blame]64 if (ns->mnt_ns)
65 get_mnt_ns(ns->mnt_ns);
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700[diff] [blame]66 if (ns->uts_ns)
67 get_uts_ns(ns->uts_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]68 if (ns->ipc_ns)
69 get_ipc_ns(ns->ipc_ns);
Cedric Le Goater9a575a92006-12-08 02:37:59 -0800[diff] [blame]70 if (ns->pid_ns)
71 get_pid_ns(ns->pid_ns);
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]72 }
73
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]74 return ns;
75}
76
77/*
78 * called from clone. This now handles copy for nsproxy and all
79 * namespaces therein.
80 */
81int copy_namespaces(int flags, struct task_struct *tsk)
82{
83 struct nsproxy *old_ns = tsk->nsproxy;
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]84 struct nsproxy *new_ns;
85 int err = 0;
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]86
87 if (!old_ns)
88 return 0;
89
90 get_nsproxy(old_ns);
91
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]92 if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]93 return 0;
94
95 new_ns = clone_namespaces(old_ns);
96 if (!new_ns) {
97 err = -ENOMEM;
98 goto out;
99 }
100
101 tsk->nsproxy = new_ns;
102
Kirill Korotaev6b3286e2006-12-08 02:37:56 -0800[diff] [blame]103 err = copy_mnt_ns(flags, tsk);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]104 if (err)
105 goto out_ns;
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]106
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700[diff] [blame]107 err = copy_utsname(flags, tsk);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]108 if (err)
109 goto out_uts;
110
111 err = copy_ipcs(flags, tsk);
112 if (err)
113 goto out_ipc;
Serge E. Hallyn4865ecf2006-10-02 02:18:14 -0700[diff] [blame]114
Cedric Le Goater9a575a92006-12-08 02:37:59 -0800[diff] [blame]115 err = copy_pid_ns(flags, tsk);
116 if (err)
117 goto out_pid;
118
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]119out:
Linus Torvalds444f3782007-01-30 13:35:18 -0800[diff] [blame]120 put_nsproxy(old_ns);
Serge E. Hallyn1651e142006-10-02 02:18:08 -0700[diff] [blame]121 return err;
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]122
Cedric Le Goater9a575a92006-12-08 02:37:59 -0800[diff] [blame]123out_pid:
124 if (new_ns->ipc_ns)
125 put_ipc_ns(new_ns->ipc_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]126out_ipc:
127 if (new_ns->uts_ns)
128 put_uts_ns(new_ns->uts_ns);
129out_uts:
Kirill Korotaev6b3286e2006-12-08 02:37:56 -0800[diff] [blame]130 if (new_ns->mnt_ns)
131 put_mnt_ns(new_ns->mnt_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]132out_ns:
133 tsk->nsproxy = old_ns;
Pavel5d124e92006-10-02 02:18:24 -0700[diff] [blame]134 kfree(new_ns);
Kirill Korotaev25b21cb2006-10-02 02:18:19 -0700[diff] [blame]135 goto out;
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]136}
137
138void free_nsproxy(struct nsproxy *ns)
139{
Cedric Le Goater9a575a92006-12-08 02:37:59 -0800[diff] [blame]140 if (ns->mnt_ns)
141 put_mnt_ns(ns->mnt_ns);
142 if (ns->uts_ns)
143 put_uts_ns(ns->uts_ns);
144 if (ns->ipc_ns)
145 put_ipc_ns(ns->ipc_ns);
146 if (ns->pid_ns)
147 put_pid_ns(ns->pid_ns);
148 kfree(ns);
Serge E. Hallynab516012006-10-02 02:18:06 -0700[diff] [blame]149}