Add check to prevent use of untagged or :latest gcr.io images in e2e tests

hack/verify-test-images.sh

+#!/bin/bash
+
+# Copyright 2014 The Kubernetes Authors All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+KUBE_ROOT=$(dirname "${BASH_SOURCE}")/..
+
+cd "${KUBE_ROOT}"
+result=0
+
+# Find mentions of untagged gcr.io images in test/e2e/*.go 
+find_e2e_test_untagged_gcr_images() {
+    grep -o -E -e 'gcr.io/[-a-z0-9/_:.]+' test/e2e/*.go | grep -v -E "gcr.io/.*:" | cut -d ":" -f 1 | sort | uniq
+}
+
+
+# Find mentions of latest gcr.io images in test/e2e/*.go 
+find_e2e_test_latest_gcr_images() {
+    grep -o -E -e 'gcr.io/.*:latest' test/e2e/*.go | cut -d ":" -f 1 | sort | uniq
+}
+
+if find_e2e_test_latest_gcr_images; then
+  echo "!!! Found :latest gcr.io images in the above files"
+  result=1
+fi
+
+if find_e2e_test_untagged_gcr_images; then
+  echo "!!! Found untagged gcr.io images in the above files"
+  result=1
+fi
+
+exit ${result}

test/e2e/volume_provisioning.go

@@ -160,7 +160,7 @@ func runInPodWithVolume(c *client.Client, ns, claimName, command string) {
 			Containers: []api.Container{
 				{
 					Name:    "volume-tester",
-					Image:   "gcr.io/google_containers/busybox",
+					Image:   "gcr.io/google_containers/busybox:1.24",
 					Command: []string{"/bin/sh"},
 					Args:    []string{"-c", command},
 					VolumeMounts: []api.VolumeMount{