Check volume node affinity before mount

pkg/volume/util/util.go

@@ -23,6 +23,7 @@ import (
 
 	"github.com/golang/glog"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/kubernetes/pkg/api/v1"
 	v1helper "k8s.io/kubernetes/pkg/api/v1/helper"
 	storage "k8s.io/kubernetes/pkg/apis/storage/v1"
@@ -164,3 +165,30 @@ func GetClassForVolume(kubeClient clientset.Interface, pv *v1.PersistentVolume)
 	}
 	return class, nil
 }
+
+// CheckNodeAffinity looks at the PV node affinity, and checks if the node has the same corresponding labels
+// This ensures that we don't mount a volume that doesn't belong to this node
+func CheckNodeAffinity(pv *v1.PersistentVolume, nodeLabels map[string]string) error {
+	affinity, err := v1helper.GetStorageNodeAffinityFromAnnotation(pv.Annotations)
+	if err != nil {
+		return fmt.Errorf("Error getting storage node affinity: %v", err)
+	}
+	if affinity == nil {
+		return nil
+	}
+
+	if affinity.RequiredDuringSchedulingIgnoredDuringExecution != nil {
+		terms := affinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms
+		glog.V(10).Infof("Match for RequiredDuringSchedulingIgnoredDuringExecution node selector terms %+v", terms)
+		for _, term := range terms {
+			selector, err := v1helper.NodeSelectorRequirementsAsSelector(term.MatchExpressions)
+			if err != nil {
+				return fmt.Errorf("Failed to parse MatchExpressions: %v", err)
+			}
+			if !selector.Matches(labels.Set(nodeLabels)) {
+				return fmt.Errorf("NodeSelectorTerm %+v does not match node labels", term.MatchExpressions)
+			}
+		}
+	}
+	return nil
+}