forked from Minki/linux
1aeb272cf0
Following an experimental deletion of the unnecessary directive #include <linux/slab.h> from the header file <linux/percpu.h>, these files under kernel/ were exposed as needing to include one of <linux/slab.h> or <linux/gfp.h>, so explicit includes were added where necessary. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
77 lines
1.6 KiB
C
77 lines
1.6 KiB
C
/*
|
|
* 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>
|
|
#include <linux/slab.h>
|
|
#include <linux/user_namespace.h>
|
|
|
|
/*
|
|
* Clone a new ns copying an original user ns, setting refcount to 1
|
|
* @old_ns: namespace to clone
|
|
* Return NULL on error (failure to kmalloc), new ns otherwise
|
|
*/
|
|
static struct user_namespace *clone_user_ns(struct user_namespace *old_ns)
|
|
{
|
|
struct user_namespace *ns;
|
|
struct user_struct *new_user;
|
|
int n;
|
|
|
|
ns = kmalloc(sizeof(struct user_namespace), GFP_KERNEL);
|
|
if (!ns)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
kref_init(&ns->kref);
|
|
|
|
for (n = 0; n < UIDHASH_SZ; ++n)
|
|
INIT_HLIST_HEAD(ns->uidhash_table + n);
|
|
|
|
/* Insert new root user. */
|
|
ns->root_user = alloc_uid(ns, 0);
|
|
if (!ns->root_user) {
|
|
kfree(ns);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
/* Reset current->user with a new one */
|
|
new_user = alloc_uid(ns, current->uid);
|
|
if (!new_user) {
|
|
free_uid(ns->root_user);
|
|
kfree(ns);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
switch_uid(new_user);
|
|
return ns;
|
|
}
|
|
|
|
struct user_namespace * copy_user_ns(int flags, struct user_namespace *old_ns)
|
|
{
|
|
struct user_namespace *new_ns;
|
|
|
|
BUG_ON(!old_ns);
|
|
get_user_ns(old_ns);
|
|
|
|
if (!(flags & CLONE_NEWUSER))
|
|
return old_ns;
|
|
|
|
new_ns = clone_user_ns(old_ns);
|
|
|
|
put_user_ns(old_ns);
|
|
return new_ns;
|
|
}
|
|
|
|
void free_user_ns(struct kref *kref)
|
|
{
|
|
struct user_namespace *ns;
|
|
|
|
ns = container_of(kref, struct user_namespace, kref);
|
|
release_uids(ns);
|
|
kfree(ns);
|
|
}
|