Commit | Line | Data |
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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> |
1651e14e | 20 | #include <linux/namespace.h> |
4865ecf1 | 21 | #include <linux/utsname.h> |
0437eb59 SH |
22 | |
23 | struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy); | |
ab516013 SH |
24 | |
25 | static inline void get_nsproxy(struct nsproxy *ns) | |
26 | { | |
27 | atomic_inc(&ns->count); | |
28 | } | |
29 | ||
30 | void 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 | */ | |
43 | static inline struct nsproxy *clone_namespaces(struct nsproxy *orig) | |
44 | { | |
45 | struct nsproxy *ns; | |
46 | ||
e05d722e AD |
47 | ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL); |
48 | if (ns) | |
ab516013 | 49 | atomic_set(&ns->count, 1); |
ab516013 SH |
50 | 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 | */ | |
58 | struct nsproxy *dup_namespaces(struct nsproxy *orig) | |
59 | { | |
60 | struct nsproxy *ns = clone_namespaces(orig); | |
61 | ||
1651e14e SH |
62 | if (ns) { |
63 | if (ns->namespace) | |
64 | get_namespace(ns->namespace); | |
4865ecf1 SH |
65 | if (ns->uts_ns) |
66 | get_uts_ns(ns->uts_ns); | |
25b21cb2 KK |
67 | if (ns->ipc_ns) |
68 | get_ipc_ns(ns->ipc_ns); | |
1651e14e SH |
69 | } |
70 | ||
ab516013 SH |
71 | return ns; |
72 | } | |
73 | ||
74 | /* | |
75 | * called from clone. This now handles copy for nsproxy and all | |
76 | * namespaces therein. | |
77 | */ | |
78 | int copy_namespaces(int flags, struct task_struct *tsk) | |
79 | { | |
80 | struct nsproxy *old_ns = tsk->nsproxy; | |
1651e14e SH |
81 | struct nsproxy *new_ns; |
82 | int err = 0; | |
ab516013 SH |
83 | |
84 | if (!old_ns) | |
85 | return 0; | |
86 | ||
87 | get_nsproxy(old_ns); | |
88 | ||
25b21cb2 | 89 | if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC))) |
1651e14e SH |
90 | 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); | |
25b21cb2 KK |
101 | if (err) |
102 | goto out_ns; | |
1651e14e | 103 | |
4865ecf1 | 104 | err = copy_utsname(flags, tsk); |
25b21cb2 KK |
105 | if (err) |
106 | goto out_uts; | |
107 | ||
108 | err = copy_ipcs(flags, tsk); | |
109 | if (err) | |
110 | goto out_ipc; | |
4865ecf1 | 111 | |
1651e14e SH |
112 | out: |
113 | put_nsproxy(old_ns); | |
114 | return err; | |
25b21cb2 KK |
115 | |
116 | out_ipc: | |
117 | if (new_ns->uts_ns) | |
118 | put_uts_ns(new_ns->uts_ns); | |
119 | out_uts: | |
120 | if (new_ns->namespace) | |
121 | put_namespace(new_ns->namespace); | |
122 | out_ns: | |
123 | tsk->nsproxy = old_ns; | |
5d124e99 | 124 | kfree(new_ns); |
25b21cb2 | 125 | goto out; |
ab516013 SH |
126 | } |
127 | ||
128 | void free_nsproxy(struct nsproxy *ns) | |
129 | { | |
1651e14e SH |
130 | if (ns->namespace) |
131 | put_namespace(ns->namespace); | |
4865ecf1 SH |
132 | if (ns->uts_ns) |
133 | put_uts_ns(ns->uts_ns); | |
25b21cb2 KK |
134 | if (ns->ipc_ns) |
135 | put_ipc_ns(ns->ipc_ns); | |
ab516013 SH |
136 | kfree(ns); |
137 | } |