78 lines
1.5 KiB
C
78 lines
1.5 KiB
C
|
/*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/module.h>
|
||
|
|
#include <linux/version.h>
|
||
|
|
#include <linux/nsproxy.h>
|
||
|
|
|
||
|
|
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 = kmalloc(sizeof(struct nsproxy), GFP_KERNEL);
|
||
|
|
if (ns) {
|
||
|
|
memcpy(ns, orig, sizeof(struct nsproxy));
|
||
|
|
atomic_set(&ns->count, 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);
|
||
|
|
|
||
|
|
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;
|
||
|
|
|
||
|
|
if (!old_ns)
|
||
|
|
return 0;
|
||
|
|
|
||
|
|
get_nsproxy(old_ns);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
void free_nsproxy(struct nsproxy *ns)
|
||
|
|
{
|
||
|
|
kfree(ns);
|
||
|
|
}
|