mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 21:54:06 +08:00
bb96a6f50b
Changelog: Feb 23: let clone_uts_ns() handle setting uts->user_ns To do so we need to pass in the task_struct who'll get the utsname, so we can get its user_ns. Feb 23: As per Oleg's coment, just pass in tsk, instead of two of its members. Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: Daniel Lezcano <daniel.lezcano@free.fr> Acked-by: David Howells <dhowells@redhat.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
82 lines
1.9 KiB
C
82 lines
1.9 KiB
C
/*
|
|
* Copyright (C) 2004 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/uts.h>
|
|
#include <linux/utsname.h>
|
|
#include <linux/err.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/user_namespace.h>
|
|
|
|
static struct uts_namespace *create_uts_ns(void)
|
|
{
|
|
struct uts_namespace *uts_ns;
|
|
|
|
uts_ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
|
|
if (uts_ns)
|
|
kref_init(&uts_ns->kref);
|
|
return uts_ns;
|
|
}
|
|
|
|
/*
|
|
* Clone a new ns copying an original utsname, setting refcount to 1
|
|
* @old_ns: namespace to clone
|
|
* Return NULL on error (failure to kmalloc), new ns otherwise
|
|
*/
|
|
static struct uts_namespace *clone_uts_ns(struct task_struct *tsk,
|
|
struct uts_namespace *old_ns)
|
|
{
|
|
struct uts_namespace *ns;
|
|
|
|
ns = create_uts_ns();
|
|
if (!ns)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
down_read(&uts_sem);
|
|
memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
|
|
ns->user_ns = get_user_ns(task_cred_xxx(tsk, user)->user_ns);
|
|
up_read(&uts_sem);
|
|
return ns;
|
|
}
|
|
|
|
/*
|
|
* Copy task tsk's utsname namespace, or clone it if flags
|
|
* specifies CLONE_NEWUTS. In latter case, changes to the
|
|
* utsname of this process won't be seen by parent, and vice
|
|
* versa.
|
|
*/
|
|
struct uts_namespace *copy_utsname(unsigned long flags,
|
|
struct task_struct *tsk)
|
|
{
|
|
struct uts_namespace *old_ns = tsk->nsproxy->uts_ns;
|
|
struct uts_namespace *new_ns;
|
|
|
|
BUG_ON(!old_ns);
|
|
get_uts_ns(old_ns);
|
|
|
|
if (!(flags & CLONE_NEWUTS))
|
|
return old_ns;
|
|
|
|
new_ns = clone_uts_ns(tsk, old_ns);
|
|
|
|
put_uts_ns(old_ns);
|
|
return new_ns;
|
|
}
|
|
|
|
void free_uts_ns(struct kref *kref)
|
|
{
|
|
struct uts_namespace *ns;
|
|
|
|
ns = container_of(kref, struct uts_namespace, kref);
|
|
put_user_ns(ns->user_ns);
|
|
kfree(ns);
|
|
}
|