userns: Make create_new_namespaces take a user_ns parameter

Modify create_new_namespaces to explicitly take a user namespace
parameter, instead of implicitly through the task_struct.

This allows an implementation of unshare(CLONE_NEWUSER) where
the new user namespace is not stored onto the current task_struct
until after all of the namespaces are created.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

1 files changed, 4 insertions, 6 deletions

diff --git a/ipc/namespace.c b/ipc/namespace.c
index 6ed33c05cb66..72c868277793 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -16,7 +16,7 @@
 
 #include "util.h"
 
-static struct ipc_namespace *create_ipc_ns(struct task_struct *tsk,
+static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns,
                                            struct ipc_namespace *old_ns)
 {
         struct ipc_namespace *ns;
@@ -46,19 +46,17 @@ static struct ipc_namespace *create_ipc_ns(struct task_struct *tsk,
         ipcns_notify(IPCNS_CREATED);
         register_ipcns_notifier(ns);
 
-        ns->user_ns = get_user_ns(task_cred_xxx(tsk, user_ns));
+        ns->user_ns = get_user_ns(user_ns);
 
         return ns;
 }
 
 struct ipc_namespace *copy_ipcs(unsigned long flags,
-                                struct task_struct *tsk)
+        struct user_namespace *user_ns, struct ipc_namespace *ns)
 {
-        struct ipc_namespace *ns = tsk->nsproxy->ipc_ns;
-
         if (!(flags & CLONE_NEWIPC))
                 return get_ipc_ns(ns);
-        return create_ipc_ns(tsk, ns);
+        return create_ipc_ns(user_ns, ns);
 }
 
 /*