Upgrade grpc-go dependency and check if file in SocketPath is actually a socket

go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/container-storage-interface/spec v1.3.0 // indirect
 	github.com/kubernetes-csi/csi-lib-utils v0.9.0
 	golang.org/x/sys v0.0.0-20200622214017-ed371f2e16b4
-	google.golang.org/grpc v1.29.0
+	google.golang.org/grpc v1.31.0
 	k8s.io/client-go v0.19.0
 	k8s.io/klog/v2 v2.2.0
 	k8s.io/kubelet v0.19.0

go.sum

@@ -350,6 +350,8 @@ google.golang.org/grpc v1.27.0 h1:rRYRFMVgRv6E0D70Skyfsr28tDXIuuPZyWGMPdMcnXg=
 google.golang.org/grpc v1.27.0/go.mod h1:qbnxyOmOxrQa7FizSgH+ReBfzJrCY1pSN7KXBS8abTk=
 google.golang.org/grpc v1.29.0 h1:2pJjwYOdkZ9HlN4sWRYBg9ttH5bCOlsueaM+b/oYjwo=
 google.golang.org/grpc v1.29.0/go.mod h1:itym6AZVZYACWQqET3MqgPpjcuV5QH3BxFS3IjizoKk=
+google.golang.org/grpc v1.31.0 h1:T7P4R73V3SSDPhH7WW7ATbfViLtmamH0DKrP3f9AuDI=
+google.golang.org/grpc v1.31.0/go.mod h1:N36X2cJ7JwdamYAgDz+s+rVMFjt3numwzf/HckM8pak=
 google.golang.org/protobuf v0.0.0-20200109180630-ec00e32a8dfd/go.mod h1:DFci5gLYBciE7Vtevhsrf46CRTquxDuWsQurQQe4oz8=
 google.golang.org/protobuf v0.0.0-20200221191635-4d8936d0db64/go.mod h1:kwYJMbMJ01Woi6D6+Kah6886xMZcty6N08ah7+eCXa0=
 google.golang.org/protobuf v0.0.0-20200228230310-ab0ca4ff8a60/go.mod h1:cfTl7dwQJ+fmap5saPgwCLgHXTUD7jkjRqWcaiX5VyM=

pkg/util/util_linux.go

@@ -44,8 +44,11 @@ func CleanupSocketFile(socketPath string) error {
 
 func DoesSocketExist(socketPath string) (bool, error) {
 	fi, err := os.Stat(socketPath)
-	if err == nil && (fi.Mode()&os.ModeSocket) != 0 {
-		return true, nil
+	if err == nil {
+		if isSocket := (fi.Mode()&os.ModeSocket != 0); isSocket {
+			return true, nil
+		}
+		return false, fmt.Errorf("file exists in socketPath %s but it's not a socket.: %+v", socketPath, fi)
 	}
 	if err != nil && !os.IsNotExist(err) {
 		return false, fmt.Errorf("failed to stat the socket %s with error: %+v", socketPath, err)

pkg/util/util_test.go

@@ -134,8 +134,8 @@ func TestSocketRegularFile(t *testing.T) {
 	f.Close()
 
 	socketExists, err := DoesSocketExist(socketPath)
-	if err != nil {
-		t.Fatalf("check for existence returned error: %+v", err)
+	if err == nil && runtime.GOOS != "windows" {
+		t.Fatalf("check for existence should returned error on linux: %+v", err)
 	}
 	// See comments in CleanupSocketFile for differences in windows and linux behavior checking for sockets.
 	if runtime.GOOS == "windows" {
@@ -147,8 +147,8 @@ func TestSocketRegularFile(t *testing.T) {
 	}
 
 	err = CleanupSocketFile(socketPath)
-	if err != nil {
-		t.Fatalf("cleanup returned error: %+v", err)
+	if err == nil && runtime.GOOS != "windows" {
+		t.Fatalf("cleanup returned should return error on linux: %+v", err)
 	}
 
 	if runtime.GOOS == "windows" {