Merge pull request #59083 from feiskyer/fix-59046

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Ensure IP is set for Azure internal loadbalancer

**What this PR does / why we need it**:

Internal Load Balancer created and associated with availability set but no target network ip configurations on Azure. And kube-controller-manager would panic because of nil pointer dereference.

This PR ensures it is set correctly.

**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #59046

**Special notes for your reviewer**:

Should cherry-pick to v1.9

**Release note**:

```release-note
Ensure IP is set for Azure internal load balancer.
```

pkg/cloudprovider/providers/azure/azure_loadbalancer.go

@@ -772,6 +772,19 @@ func (az *Cloud) reconcileLoadBalancer(clusterName string, service *v1.Service,
 				glog.V(2).Infof("ensure(%s) abort backoff: lb(%s) - updating", serviceName, lbName)
 				return nil, err
 			}
+
+			if isInternal {
+				// Refresh updated lb which will be used later in other places.
+				newLB, exist, err := az.getAzureLoadBalancer(lbName)
+				if err != nil {
+					glog.V(2).Infof("getAzureLoadBalancer(%s) failed: %v", lbName, err)
+					return nil, err
+				}
+				if !exist {
+					return nil, fmt.Errorf("load balancer %q not found", lbName)
+				}
+				lb = &newLB
+			}
 		}
 	}
 

pkg/cloudprovider/providers/azure/azure_wrap.go

@@ -173,3 +173,19 @@ func (az *Cloud) getSubnet(virtualNetworkName string, subnetName string) (subnet
 
 	return subnet, exists, err
 }
+
+func (az *Cloud) getAzureLoadBalancer(name string) (lb network.LoadBalancer, exists bool, err error) {
+	var realErr error
+
+	lb, err = az.LoadBalancerClient.Get(az.ResourceGroup, name, "")
+	exists, realErr = checkResourceExistsFromError(err)
+	if realErr != nil {
+		return lb, false, realErr
+	}
+
+	if !exists {
+		return lb, false, nil
+	}
+
+	return lb, exists, err
+}