mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-12 21:36:44 +07:00
5d124e99c2
This patch fixes copy_namespaces()'s error path. when new nsproxy (new_ns) is created pointers to namespaces (ipc, uts) are copied from the old nsproxy. Later in copy_utsname, copy_ipcs, etc. according namespaces are get-ed. On error path needed namespaces are put-ed, so there's no need to put new nsproxy itelf as it woud cause putting namespaces for the second time. Found when incorporating namespaces into OpenVZ kernel. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
140 lines
2.7 KiB
C
140 lines
2.7 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.
|
|
*
|
|
* 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/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 = 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);
|
|
|
|
if (ns) {
|
|
if (ns->namespace)
|
|
get_namespace(ns->namespace);
|
|
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_namespace(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->namespace)
|
|
put_namespace(new_ns->namespace);
|
|
out_ns:
|
|
tsk->nsproxy = old_ns;
|
|
kfree(new_ns);
|
|
goto out;
|
|
}
|
|
|
|
void free_nsproxy(struct nsproxy *ns)
|
|
{
|
|
if (ns->namespace)
|
|
put_namespace(ns->namespace);
|
|
if (ns->uts_ns)
|
|
put_uts_ns(ns->uts_ns);
|
|
if (ns->ipc_ns)
|
|
put_ipc_ns(ns->ipc_ns);
|
|
kfree(ns);
|
|
}
|