Fixes machineset paused condition nil pointer

This change fixes a potential nil pointer error when failing to set the
paused condition in the machineset controller.

It captures the name of the machineset before calling the update status
function, where if there is a failure the machineset passed is set to
nil.

Author: theobarberbany

pkg/controller/machineset/controller.go

@@ -174,6 +174,7 @@ func (r *ReconcileMachineSet) Reconcile(ctx context.Context, request reconcile.R
 	}
 
 	if r.gate.Enabled(featuregate.Feature(openshiftfeatures.FeatureGateMachineAPIMigration)) {
+		machineSetName := machineSet.GetName()
 		machineSetCopy := machineSet.DeepCopy()
 		// Check Status.AuthoritativeAPI. If it's not set to MachineAPI. Set the
 		// paused condition true and return early.
@@ -188,12 +189,15 @@ func (r *ReconcileMachineSet) Reconcile(ctx context.Context, request reconcile.R
 				"The AuthoritativeAPI is set to %s", string(machineSet.Status.AuthoritativeAPI),
 			))
 
-			machineSet, err := updateMachineSetStatus(r.Client, machineSet, machineSetCopy.Status)
-			if err != nil {
-				klog.Errorf("%v: error updating status: %v", machineSetCopy.Name, err)
+			_, err := updateMachineSetStatus(r.Client, machineSet, machineSetCopy.Status)
+			if err != nil && !apierrors.IsNotFound(err) {
+				klog.Errorf("%v: error updating status: %v", machineSetName, err)
+				return reconcile.Result{}, fmt.Errorf("error updating status: %w", err)
+			} else if apierrors.IsNotFound(err) {
+				return reconcile.Result{}, nil
 			}
 
-			klog.Infof("%v: machine set is paused, taking no further action", machineSet.Name)
+			klog.Infof("%v: machine set is paused, taking no further action", machineSetName)
 			return reconcile.Result{}, nil
 		}
 
@@ -212,11 +216,17 @@ func (r *ReconcileMachineSet) Reconcile(ctx context.Context, request reconcile.R
 			"%s",
 			pausedFalseReason,
 		))
-		machineSet, err := updateMachineSetStatus(r.Client, machineSet, machineSetCopy.Status)
-		if err != nil {
-			klog.Errorf("%v: error updating status: %v", machineSetCopy.Name, err)
+
+		var err error
+		machineSet, err = updateMachineSetStatus(r.Client, machineSet, machineSetCopy.Status)
+		if err != nil && !apierrors.IsNotFound(err) {
+			klog.Errorf("%v: error updating status: %v", machineSetName, err)
+			return reconcile.Result{}, fmt.Errorf("error updating status: %w", err)
+		} else if apierrors.IsNotFound(err) {
+			return reconcile.Result{}, nil
 		}
-		klog.Infof("%v: setting paused to false and continuing reconcile", machineSet.Name)
+
+		klog.Infof("%v: setting paused to false and continuing reconcile", machineSetName)
 	}
 
 	result, err := r.reconcile(ctx, machineSet)