--- a/src/java.base/share/classes/java/io/ObjectInputStream.java	Wed May 23 15:57:51 2018 +0000
+++ b/src/java.base/share/classes/java/io/ObjectInputStream.java	Fri May 25 13:29:25 2018 -0400
@@ -1263,9 +1263,11 @@
         if (serialFilter != null) {
             RuntimeException ex = null;
             ObjectInputFilter.Status status;
+            // Info about the stream is not available if overridden by subclass, return 0
+            long bytesRead = (bin == null) ? 0 : bin.getBytesRead();
             try {
                 status = serialFilter.checkInput(new FilterValues(clazz, arrayLength,
-                        totalObjectRefs, depth, bin.getBytesRead()));
+                        totalObjectRefs, depth, bytesRead));
             } catch (RuntimeException e) {
                 // Preventive interception of an exception to log
                 status = ObjectInputFilter.Status.REJECTED;
@@ -1277,7 +1279,7 @@
                                 ? Logger.Level.DEBUG
                                 : Logger.Level.TRACE,
                         "ObjectInputFilter {0}: {1}, array length: {2}, nRefs: {3}, depth: {4}, bytes: {5}, ex: {6}",
-                        status, clazz, arrayLength, totalObjectRefs, depth, bin.getBytesRead(),
+                        status, clazz, arrayLength, totalObjectRefs, depth, bytesRead,
                         Objects.toString(ex, "n/a"));
             }
             if (status == null ||

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/io/Serializable/serialFilter/CheckArrayTest.java	Fri May 25 13:29:25 2018 -0400
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2018, 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.
+ *
+ * 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.
+ */
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.ObjectInputFilter;
+import java.io.ObjectInputStream;
+import java.io.InvalidClassException;
+
+import java.util.Hashtable;
+
+import jdk.internal.misc.SharedSecrets;
+
+import org.testng.annotations.BeforeClass;
+import org.testng.annotations.DataProvider;
+import org.testng.annotations.Test;
+import org.testng.Assert;
+
+/* @test
+ * @build CheckArrayTest SerialFilterTest
+ * @bug 8203368
+ * @modules java.base/jdk.internal.misc
+ * @run testng CheckArrayTest
+ *
+ * @summary Test the SharedSecret access to ObjectInputStream.checkArray works
+ *      with overridden subclasses.
+ */
+
+/**
+ * Verify that the SharedSecret access to the OIS checkAccess method
+ * does not fail with NPE in the case where ObjectInputStream is subclassed.
+ * The checkAccess method is called from various aggregate types in java.util
+ * to check array sizes during deserialization via the ObjectInputFilter attached the stream.
+ * The filterCheck must be resilent to an InputStream not being available (only the subclass knows).
+ */
+public class CheckArrayTest {
+
+    @DataProvider(name = "Patterns")
+    Object[][] patterns() {
+        return new Object[][]{
+                new Object[]{"maxarray=10", 10, new String[10]},    // successful
+                new Object[]{"maxarray=10", 11, new String[11]},    // exception expected
+        };
+    }
+
+    /**
+     * Test SharedSecrets checkArray with unmodified ObjectInputStream.
+     */
+    @Test(dataProvider = "Patterns")
+    public void normalOIS(String pattern, int arraySize, Object[] array) throws IOException {
+        ObjectInputFilter filter = ObjectInputFilter.Config.createFilter(pattern);
+        byte[] bytes = SerialFilterTest.writeObjects(array);
+        try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
+             ObjectInputStream ois = new ObjectInputStream(bais)) {
+            // Check the arraysize against the filter
+            try {
+                ois.setObjectInputFilter(filter);
+                SharedSecrets.getJavaObjectInputStreamAccess()
+                        .checkArray(ois, array.getClass(), arraySize);
+                Assert.assertTrue(array.length >= arraySize,
+                        "Should have thrown InvalidClassException due to array size");
+            } catch (InvalidClassException ice) {
+                Assert.assertFalse(array.length > arraySize,
+                        "Should NOT have thrown InvalidClassException due to array size");
+            }
+        }
+    }
+
+    /**
+     * Test SharedSecrets checkArray with an ObjectInputStream subclassed to
+     * handle all input stream functions.
+     */
+    @Test(dataProvider = "Patterns")
+    public void subclassedOIS(String pattern, int arraySize, Object[] array) throws IOException {
+        byte[] bytes = SerialFilterTest.writeObjects(array);
+        try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
+             ObjectInputStream ois = new MyInputStream(bais)) {
+            // Check the arraysize against the filter
+            ObjectInputFilter filter = ObjectInputFilter.Config.createFilter(pattern);
+            ois.setObjectInputFilter(filter);
+            SharedSecrets.getJavaObjectInputStreamAccess()
+                    .checkArray(ois, array.getClass(), arraySize);
+            Assert.assertTrue(array.length >= arraySize,
+                    "Should have thrown InvalidClassException due to array size");
+        } catch (InvalidClassException ice) {
+            Assert.assertFalse(array.length > arraySize,
+                    "Should NOT have thrown InvalidClassException due to array size");
+        }
+    }
+
+    /**
+     * Subclass OIS to disable all input stream functions of the OIS.
+     */
+    static class MyInputStream extends ObjectInputStream {
+        MyInputStream(InputStream is) throws IOException {
+            super();
+        }
+
+        public void close() {
+        }
+    }
+}