Add opt-in parameter to disable node mutation permissions

Author: dankova22

charts/aws-efs-csi-driver/templates/node-daemonset.yaml

@@ -96,6 +96,10 @@ spec:
             - name: AWS_USE_FIPS_ENDPOINT
               value: "true"
             {{- end }}
+            {{- if .Values.node.serviceAccount.disableMutation }}
+            - name: DISABLE_TAINT_WATCHER
+              value: "true"
+            {{- end }}
             - name: PORT_RANGE_UPPER_BOUND
               value: "{{ .Values.portRangeUpperBound }}"
             {{- with .Values.node.env }}

charts/aws-efs-csi-driver/templates/node-serviceaccount.yaml

@@ -21,7 +21,12 @@ metadata:
 rules:
   - apiGroups: [""]
     resources: ["nodes"]
-    verbs: ["get", "list", "watch", "patch"]
+    verbs: ["get", "list", "watch"]
+  {{- if not .Values.node.serviceAccount.disableMutation }}
+  - apiGroups: [""]
+    resources: ["nodes"]
+    verbs: ["patch"]
+  {{- end }}
 ---
 kind: ClusterRoleBinding
 apiVersion: rbac.authorization.k8s.io/v1

charts/aws-efs-csi-driver/values.yaml

@@ -204,6 +204,10 @@ node:
     annotations: {}
     ## Enable if EKS IAM for SA is used
     #  eks.amazonaws.com/role-arn: arn:aws:iam::111122223333:role/efs-csi-role
+    # Disable mutating permissions for the node service account.
+    # When disableMutation is true, some features of the EFS CSI Driver node pods will not function, such as taint removal.
+    # Primarily useful in particularly security-sensitive environments, or on multi-tenant clusters that isolate tenants by node.
+    disableMutation: false
   healthPort: 9809
   # securityContext on the node pod
   securityContext:

deploy/kubernetes/base/node-serviceaccount.yaml

@@ -16,7 +16,10 @@ metadata:
 rules:
   - apiGroups: [""]
     resources: ["nodes"]
-    verbs: ["get", "list", "watch", "patch"]
+    verbs: ["get", "list", "watch"]
+  - apiGroups: [""]
+    resources: ["nodes"]
+    verbs: ["patch"]
 ---
 kind: ClusterRoleBinding
 apiVersion: rbac.authorization.k8s.io/v1

pkg/driver/node.go

@@ -488,6 +488,11 @@ type JSONPatch struct {
 // This taint can be optionally applied by users to prevent startup race conditions such as
 // https://github.com/kubernetes/kubernetes/issues/95911
 func removeNotReadyTaint(k8sClient cloud.KubernetesAPIClient) error {
+	if os.Getenv("DISABLE_TAINT_WATCHER") != "" {
+		klog.V(4).InfoS("DISABLE_TAINT_WATCHER set, skipping taint removal")
+		return nil
+	}
+
 	nodeName := os.Getenv("CSI_NODE_NAME")
 	if nodeName == "" {
 		klog.V(4).InfoS("CSI_NODE_NAME missing, skipping taint removal")