Check volumespec is nil in FindPluginBySpec

pkg/volume/plugins.go

@@ -387,6 +387,10 @@ func (pm *VolumePluginMgr) FindPluginBySpec(spec *Spec) (VolumePlugin, error) {
 	pm.mutex.Lock()
 	defer pm.mutex.Unlock()
 
+	if spec == nil {
+		return nil, fmt.Errorf("Could not find plugin because volume spec is nil")
+	}
+
 	matches := []string{}
 	for k, v := range pm.plugins {
 		if v.CanSupport(spec) {

pkg/volume/plugins_test.go

@@ -112,6 +112,17 @@ func TestVolumePluginMgrFunc(t *testing.T) {
 	if plug.GetPluginName() != "testPlugin" {
 		t.Errorf("Wrong name: %s", plug.GetPluginName())
 	}
+
+	plug, err = vpm.FindPluginBySpec(nil)
+	if err == nil {
+		t.Errorf("Should return error if volume spec is nil")
+	}
+
+	volumeSpec := &Spec{}
+	plug, err = vpm.FindPluginBySpec(volumeSpec)
+	if err != nil {
+		t.Errorf("Should return test plugin if volume spec is not nil")
+	}
 }
 
 func Test_ValidatePodTemplate(t *testing.T) {