cred: Refcount the user_ns pointed to by the cred.

struct user_struct will shortly loose it's user_ns reference
so make the cred user_ns reference a proper reference complete
with reference counting.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This commit is contained in:
Eric W. Biederman 2011-11-16 21:52:53 -08:00
parent c4a4d60379
commit 0093ccb68f
4 changed files with 10 additions and 10 deletions

View file

@ -148,6 +148,7 @@ static void put_cred_rcu(struct rcu_head *rcu)
if (cred->group_info)
put_group_info(cred->group_info);
free_uid(cred->user);
put_user_ns(cred->user_ns);
kmem_cache_free(cred_jar, cred);
}
@ -303,6 +304,7 @@ struct cred *prepare_creds(void)
set_cred_subscribers(new, 0);
get_group_info(new->group_info);
get_uid(new->user);
get_user_ns(new->user_ns);
#ifdef CONFIG_KEYS
key_get(new->thread_keyring);
@ -412,11 +414,6 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags)
goto error_put;
}
/* cache user_ns in cred. Doesn't need a refcount because it will
* stay pinned by cred->user
*/
new->user_ns = new->user->user_ns;
#ifdef CONFIG_KEYS
/* new threads get their own thread keyrings if their parent already
* had one */
@ -676,6 +673,7 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
atomic_set(&new->usage, 1);
set_cred_subscribers(new, 0);
get_uid(new->user);
get_user_ns(new->user_ns);
get_group_info(new->group_info);
#ifdef CONFIG_KEYS