Fix nil pointer dereference on error
Fix nil pointer dereference on error

warmchang/minikube,dlorenc/minikube,warmchang/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube,dlorenc/minikube,dlorenc/minikube,dlorenc/minikube,dlorenc/minikube,warmchang/minikube,kubernetes/minikube,warmchang/minikube,dlorenc/minikube,kubernetes/minikube,warmchang/minikube,kubernetes/minikube,dalehamel/minikube,kubernetes/minikube,dlorenc/minikube,kubernetes/minikube,dalehamel/minikube,dalehamel/minikube,dlorenc/minikube,kubernetes/minikube