8175325: NetworkInterface.getInterfaceAddresses throws NPE when no addresses

Reviewed-by: chegar, martin

jdk/src/java.base/share/classes/java/net/NetworkInterface.java

 /*
- * Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2017, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -175,14 +175,16 @@ public final class NetworkInterface {
      */
     public java.util.List<InterfaceAddress> getInterfaceAddresses() {
         java.util.List<InterfaceAddress> lst = new java.util.ArrayList<>(1);
-        SecurityManager sec = System.getSecurityManager();
-        for (int j=0; j<bindings.length; j++) {
-            try {
-                if (sec != null) {
-                    sec.checkConnect(bindings[j].getAddress().getHostAddress(), -1);
-                }
-                lst.add(bindings[j]);
-            } catch (SecurityException e) { }
+        if (bindings != null) {
+            SecurityManager sec = System.getSecurityManager();
+            for (int j=0; j<bindings.length; j++) {
+                try {
+                    if (sec != null) {
+                        sec.checkConnect(bindings[j].getAddress().getHostAddress(), -1);
+                    }
+                    lst.add(bindings[j]);
+                } catch (SecurityException e) { }
+            }
         }
         return lst;
     }

jdk/test/java/net/MulticastSocket/NetworkInterfaceEmptyGetInetAddressesTest.java

+/*
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @bug 8175325
+ * @summary test NetworkInterface getInterfaceAddresses method on the NetworkInterface returned
+ * from the getNetworkInterface invocation on a MulticastSocket bound to a wildcard address.
+ *
+ */
+
+import java.net.MulticastSocket;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+
+public class NetworkInterfaceEmptyGetInetAddressesTest {
+
+    static int exceptionCount = 0;
+
+    public static void testMethods(NetworkInterface netIf) throws Exception {
+        testNetworkInterface_getInterfaceAddresses(netIf);
+
+        if (exceptionCount > 0) {
+            throw new RuntimeException("Unexpected Exceptions in test");
+        }
+    }
+
+    private static void testNetworkInterface_getInterfaceAddresses(
+            NetworkInterface netIf) {
+        try {
+            netIf.getInterfaceAddresses();
+        } catch (Exception ex) {
+            ex.printStackTrace();
+            incrementExceptionCount();
+        }
+    }
+
+    private static void incrementExceptionCount() {
+        exceptionCount++;
+    }
+
+    public static void main(String[] args) throws Exception {
+        MulticastSocket mcastSock = null;
+        try {
+            mcastSock = new MulticastSocket();
+            System.out.println("macst socket address == "
+                    + mcastSock.getLocalAddress());
+            NetworkInterface netIf = mcastSock.getNetworkInterface();
+            testMethods(netIf);
+        } finally {
+            if (mcastSock != null) {
+                mcastSock.close();
+            }
+        }
+    }
+}