From 8b7e9d303c198d99725cb528b0e0df7dbf529cd7 Mon Sep 17 00:00:00 2001
From: gmarek <gmarek@google.com>
Date: Thu, 13 Oct 2016 11:19:00 +0200
Subject: [PATCH] Handle DeletedFinalStateUnknown in NodeController

---
 pkg/controller/node/nodecontroller.go | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/pkg/controller/node/nodecontroller.go b/pkg/controller/node/nodecontroller.go
index 8b2720c53c706..3680c32b04606 100644
--- a/pkg/controller/node/nodecontroller.go
+++ b/pkg/controller/node/nodecontroller.go
@@ -294,7 +294,20 @@ func NewNodeController(
 					return
 				}
 
-				node := obj.(*api.Node)
+				node, isNode := obj.(*api.Node)
+				// We can get DeletedFinalStateUnknown instead of *api.Node here and we need to handle that correctly. #34692
+				if !isNode {
+					deletedState, ok := obj.(cache.DeletedFinalStateUnknown)
+					if !ok {
+						glog.Errorf("Received unexpected object: %v", obj)
+						return
+					}
+					node, ok = deletedState.Obj.(*api.Node)
+					if !ok {
+						glog.Errorf("DeletedFinalStateUnknown contained non-Node object: %v", deletedState.Obj)
+						return
+					}
+				}
 				if err := nc.cidrAllocator.ReleaseCIDR(node); err != nil {
 					glog.Errorf("Error releasing CIDR: %v", err)
 				}