mirror of
https://github.com/torvalds/linux.git
synced 2024-12-01 00:21:32 +00:00
e3222c4ecc
sys_clone() and sys_unshare() both makes copies of nsproxy and its associated namespaces. But they have different code paths. This patch merges all the nsproxy and its associated namespace copy/clone handling (as much as possible). Posted on container list earlier for feedback. - Create a new nsproxy and its associated namespaces and pass it back to caller to attach it to right process. - Changed all copy_*_ns() routines to return a new copy of namespace instead of attaching it to task->nsproxy. - Moved the CAP_SYS_ADMIN checks out of copy_*_ns() routines. - Removed unnessary !ns checks from copy_*_ns() and added BUG_ON() just incase. - Get rid of all individual unshare_*_ns() routines and make use of copy_*_ns() instead. [akpm@osdl.org: cleanups, warning fix] [clg@fr.ibm.com: remove dup_namespaces() declaration] [serue@us.ibm.com: fix CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) retval] [akpm@linux-foundation.org: fix build with CONFIG_SYSVIPC=n] Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: <containers@lists.osdl.org> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
63 lines
1.4 KiB
C
63 lines
1.4 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/version.h>
|
|
|
|
/*
|
|
* 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 uts_namespace *old_ns)
|
|
{
|
|
struct uts_namespace *ns;
|
|
|
|
ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
|
|
if (ns) {
|
|
memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
|
|
kref_init(&ns->kref);
|
|
}
|
|
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(int flags, struct uts_namespace *old_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(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);
|
|
kfree(ns);
|
|
}
|