undefect. CWE-407 — 63 sites patched across 27 ecosystems

Authors: russell@unturf.com · brackishbert@gmail.com · foxhop.net · TimeHexOn.com

Patches, unit tests, benchmarks, whitepaper, and outreach briefs.
Public domain — no copyright claimed. Use freely.

test/hotspot/jtreg/runtime/ParallelLoad/ParallelCircularity/ParallelCircularityTest.java

@@ -0,0 +1,116 @@
+/*
+ * Copyright (c) 2022, 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.
+ */
+
+/*
+ * @test
+ * @bug 4699981 8295278
+ * @summary This is a testcase for JDK-4699981. When 2 threads are loading the same class with
+ *           the same classloader, and somehow one of the 2 threads releases the
+ *           synchronization lock on the classloader, the JVM code
+ *           throws ClassCircularityError, mistakenly.
+ * @library /test/lib
+ * @compile test-classes/Base.java test-classes/Derived.java test-classes/Support.java
+ * @run main/othervm ParallelCircularityTest
+ */
+
+import java.net.URL;
+import java.net.URLClassLoader;
+
+public class ParallelCircularityTest {
+
+    private Object lock = new Object();
+
+    private void test() throws Exception {
+       URL location = getClass().getProtectionDomain().getCodeSource().getLocation();
+       URLLoader loader = new URLLoader(new URL[] {location}, getClass().getClassLoader().getParent());
+
+       Class cls = loader.loadClass("Support");
+
+       Thread t1 = new Thread(new Run1(cls));
+       t1.start();
+
+       Thread.sleep(1000);
+
+       // Load Derived, will trigger a loadClassInternal for Base
+       loader.loadClass("Derived");
+    }
+
+    public static void main(String[] args) throws Exception {
+        ParallelCircularityTest pct = new ParallelCircularityTest();
+        pct.test();
+    }
+
+    public class URLLoader extends URLClassLoader {
+       private boolean m_firstTime = true;
+
+       public URLLoader(URL[] urls, ClassLoader parent) {
+          super(urls, parent);
+       }
+
+       public Class loadClass(String name) throws ClassNotFoundException {
+          if (name.equals("Base")) {
+             if (m_firstTime) {
+                m_firstTime = false;
+
+                // Notify the other thread
+                synchronized (lock) {
+                   lock.notifyAll();
+                }
+
+                // Wait on the classloader to have the JVM throw ClassCircularityError
+                try {
+                   synchronized (this) {
+                      wait(5000);
+                   }
+                }
+                catch (InterruptedException ignored) { }
+             }
+          }
+          return super.loadClass(name);
+       }
+    }
+
+    public class Run1 implements Runnable {
+       private Class cls;
+
+       public Run1(Class cls) {
+          this.cls = cls;
+       }
+
+       public void run() {
+          synchronized (lock) {
+             try {
+                lock.wait();
+             }
+             catch (InterruptedException ignored) {}
+          }
+
+          // Trigger loadClassInternal for Base
+          try {
+             cls.newInstance();
+          } catch (Throwable x) {
+             x.printStackTrace();
+          }
+       }
+    }
+}