1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
/*
* Copyright (C) 2006 IBM Corporation
*
* Author: Serge Hallyn <serue@us.ibm.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2 of the
* License.
*
* Jun 2006 - namespaces support
* OpenVZ, SWsoft Inc.
* Pavel Emelianov <xemul@openvz.org>
*/
#include <linux/module.h>
#include <linux/version.h>
#include <linux/nsproxy.h>
#include <linux/init_task.h>
#include <linux/mnt_namespace.h>
#include <linux/utsname.h>
struct nsproxy init_nsproxy = INIT_NSPROXY(init_nsproxy);
static inline void get_nsproxy(struct nsproxy *ns)
{
atomic_inc(&ns->count);
}
void get_task_namespaces(struct task_struct *tsk)
{
struct nsproxy *ns = tsk->nsproxy;
if (ns) {
get_nsproxy(ns);
}
}
/*
* creates a copy of "orig" with refcount 1.
* This does not grab references to the contained namespaces,
* so that needs to be done by dup_namespaces.
*/
static inline struct nsproxy *clone_namespaces(struct nsproxy *orig)
{
struct nsproxy *ns;
ns = kmemdup(orig, sizeof(struct nsproxy), GFP_KERNEL);
if (ns) {
atomic_set(&ns->count, 1);
ns->id = -1;
}
return ns;
}
/*
* copies the nsproxy, setting refcount to 1, and grabbing a
* reference to all contained namespaces. Called from
* sys_unshare()
*/
struct nsproxy *dup_namespaces(struct nsproxy *orig)
{
struct nsproxy *ns = clone_namespaces(orig);
if (ns) {
if (ns->mnt_ns)
get_mnt_ns(ns->mnt_ns);
if (ns->uts_ns)
get_uts_ns(ns->uts_ns);
if (ns->ipc_ns)
get_ipc_ns(ns->ipc_ns);
}
return ns;
}
/*
* called from clone. This now handles copy for nsproxy and all
* namespaces therein.
*/
int copy_namespaces(int flags, struct task_struct *tsk)
{
struct nsproxy *old_ns = tsk->nsproxy;
struct nsproxy *new_ns;
int err = 0;
if (!old_ns)
return 0;
get_nsproxy(old_ns);
if (!(flags & (CLONE_NEWNS | CLONE_NEWUTS | CLONE_NEWIPC)))
return 0;
new_ns = clone_namespaces(old_ns);
if (!new_ns) {
err = -ENOMEM;
goto out;
}
tsk->nsproxy = new_ns;
err = copy_mnt_ns(flags, tsk);
if (err)
goto out_ns;
err = copy_utsname(flags, tsk);
if (err)
goto out_uts;
err = copy_ipcs(flags, tsk);
if (err)
goto out_ipc;
out:
put_nsproxy(old_ns);
return err;
out_ipc:
if (new_ns->uts_ns)
put_uts_ns(new_ns->uts_ns);
out_uts:
if (new_ns->mnt_ns)
put_mnt_ns(new_ns->mnt_ns);
out_ns:
tsk->nsproxy = old_ns;
kfree(new_ns);
goto out;
}
void free_nsproxy(struct nsproxy *ns)
{
if (ns->mnt_ns)
put_mnt_ns(ns->mnt_ns);
if (ns->uts_ns)
put_uts_ns(ns->uts_ns);
if (ns->ipc_ns)
put_ipc_ns(ns->ipc_ns);
kfree(ns);
}
|
