Don't bypass selector provisioning when not default deny

If we have namespaces Source and Destination, and Destination
contains a NetworkPolicy allowing access from Source, we need
to provision the ipsets for Source and add them to relevant
selectors, even though Source is DefaultAllow.

This also fixes an issue where if the Namespace labels are updated,
that would be ignored.

Fixes #3059

npc/namespace.go

@@ -265,7 +265,9 @@ func (ns *ns) addNamespace(obj *coreapi.Namespace) error {
 
 	// Insert a rule to bypass policies if namespace is DefaultAllow
 	if !isDefaultDeny(obj) {
-		return ns.ensureBypassRule(ns.allPods.ipsetName)
+		if err := ns.ensureBypassRule(ns.allPods.ipsetName); err != nil {
+			return err
+		}
 	}
 
 	// Add namespace ipset to matching namespace selectors
@@ -282,10 +284,14 @@ func (ns *ns) updateNamespace(oldObj, newObj *coreapi.Namespace) error {
 	if oldDefaultDeny != newDefaultDeny {
 		common.Log.Infof("namespace DefaultDeny changed from %t to %t", oldDefaultDeny, newDefaultDeny)
 		if oldDefaultDeny {
-			return ns.ensureBypassRule(ns.allPods.ipsetName)
+			if err := ns.ensureBypassRule(ns.allPods.ipsetName); err != nil {
+				return err
+			}
 		}
 		if newDefaultDeny {
-			return ns.deleteBypassRule(ns.allPods.ipsetName)
+			if err := ns.deleteBypassRule(ns.allPods.ipsetName); err != nil {
+				return err
+			}
 		}
 	}
 
@@ -318,7 +324,9 @@ func (ns *ns) deleteNamespace(obj *coreapi.Namespace) error {
 
 	// Remove bypass rule
 	if !isDefaultDeny(obj) {
-		return ns.deleteBypassRule(ns.allPods.ipsetName)
+		if err := ns.deleteBypassRule(ns.allPods.ipsetName); err != nil {
+			return err
+		}
 	}
 
 	// Remove namespace ipset from any matching namespace selectors