[PATCH] ipcns: fix !CONFIG_IPC_NS behavior

When CONFIG_IPC_NS=n, clone(CLONE_NEWIPC) claims success, but did not actually
clone a new IPC namespace.

Fix this to return -EINVAL so the caller knows his request was denied.

Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ipc/util.c

@@ -144,6 +144,13 @@ void free_ipc_ns(struct kref *kref)
 	shm_exit_ns(ns);
 	kfree(ns);
 }
+#else
+int copy_ipcs(unsigned long flags, struct task_struct *tsk)
+{
+	if (flags & CLONE_NEWIPC)
+		return -EINVAL;
+	return 0;
+}
 #endif
 
 /**