userns: Use cred->user_ns instead of cred->user->user_ns
Optimize performance and prepare for the removal of the user_ns reference
from user_struct. Remove the slow long walk through cred->user->user_ns and
instead go straight to cred->user_ns.
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/kernel/utsname.c b/kernel/utsname.c
index 405caf9..679d97a 100644
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -43,7 +43,7 @@
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);
+ ns->user_ns = get_user_ns(task_cred_xxx(tsk, user_ns));
up_read(&uts_sem);
return ns;
}