8058216: NetworkInterface.getHardwareAddress can return zero length byte array...

8058216: NetworkInterface.getHardwareAddress can return zero length byte array when run with preferIPv4Stack
Reviewed-by: michaelm

src/windows/native/java/net/NetworkInterface.c

@@ -1014,9 +1014,11 @@ JNIEXPORT jbyteArray JNICALL Java_java_net_NetworkInterface_getMacAddr0
       case MIB_IF_TYPE_FDDI:
       case IF_TYPE_IEEE80211:
         len = ifRowP->dwPhysAddrLen;
-        ret = (*env)->NewByteArray(env, len);
-        if (!IS_NULL(ret)) {
-          (*env)->SetByteArrayRegion(env, ret, 0, len, (jbyte *) ifRowP->bPhysAddr);
+        if (len > 0) {
+            ret = (*env)->NewByteArray(env, len);
+            if (!IS_NULL(ret)) {
+              (*env)->SetByteArrayRegion(env, ret, 0, len, (jbyte *) ifRowP->bPhysAddr);
+            }
         }
         break;
       }

test/java/net/NetworkInterface/Test.java

@@ -22,7 +22,9 @@
  */
 
 /* @test
- * @bug 4405354 6594296
+ * @bug 4405354 6594296 8058216
+ * @run main Test
+ * @run main/othervm -Djava.net.preferIPv4Stack=true Test
  * @summary Basic tests for NetworkInterface
  */
 import java.net.NetworkInterface;