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/jdk/java/lang/Thread/virtual/stress/TimedWaitALot.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright (c) 2024, 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 id=timeout
+ * @summary Stress test timed-Object.wait
+ * @run main TimedWaitALot 200
+ */
+
+/*
+ * @test id=timeout-notify
+ * @summary Test timed-Object.wait where the waiting thread is awakened with Object.notify
+ *     at around the same time that the timeout expires.
+ * @run main TimedWaitALot 150 true false
+ */
+
+/*
+ * @test id=timeout-interrupt
+ * @summary Test timed-Object.wait where the waiting thread is awakened with Thread.interrupt
+ *     at around the same time that the timeout expires.
+ * @run main TimedWaitALot 150 false true
+ */
+
+/*
+ * @test id=timeout-notify-interrupt
+ * @summary Test timed-Object.wait where the waiting thread is awakened with Object.notify
+ *     and Thread.interrupt at around the same time that the timeout expires.
+ * @run main TimedWaitALot 100 true true
+ */
+
+import java.time.Instant;
+import java.util.concurrent.Executors;
+import java.util.concurrent.SynchronousQueue;
+import java.util.concurrent.ThreadLocalRandom;
+
+public class TimedWaitALot {
+    public static void main(String[] args) throws Exception {
+        int iterations = Integer.parseInt(args[0]);
+        boolean notify = args.length >= 2 && "true".equals(args[1]);
+        boolean interrupt = args.length >=3 && "true".equals(args[2]);
+
+        // test all timeouts concurrently
+        int[] timeouts = { 10, 20, 50, 100 };
+        for (int i = 1; i <= iterations; i++) {
+            System.out.println(Instant.now() + " => " + i + " of " + iterations);
+            test(notify, interrupt, timeouts);
+        }
+    }
+
+    /**
+     * Start a first virtual thread to wait in Object.wait(millis).
+     * If {@code notify} is true, start a virtual thread to use Object.notifyAll at around
+     * the same time that the timeout expires.
+     * If {@code interrupt} is true, start virtual thread to interrupts the first virtual
+     * thread at around the same time as the timeout expires.
+     */
+    static void test(boolean notify, boolean interrupt, int... timeouts) throws Exception {
+        try (var executor = Executors.newVirtualThreadPerTaskExecutor()) {
+            for (int timeout : timeouts) {
+                var queue = new SynchronousQueue<Thread>();
+                var lock = new Object();
+
+                // virtual thread waits with Object.wait(timeout)
+                executor.submit(() -> {
+                    queue.put(Thread.currentThread());
+                    synchronized (lock) {
+                        lock.wait(timeout);
+                    }
+                    return null;
+                });
+
+                // wait for thread to start
+                Thread thread = queue.take();
+
+                // start thread to Object.notifyAll at around time that the timeout expires
+                if (notify) {
+                    executor.submit(() -> {
+                        if (ThreadLocalRandom.current().nextBoolean()) {
+                            synchronized (lock) {
+                                sleepLessThan(timeout);
+                                lock.notifyAll();
+                            }
+                        } else {
+                            sleepLessThan(timeout);
+                            synchronized (lock) {
+                                lock.notifyAll();
+                            }
+                        }
+                        return null;
+                    });
+                }
+
+                // start thread to interrupt first thread at around time that the timeout expires
+                if (interrupt) {
+                    executor.submit(() -> {
+                        sleepLessThan(timeout);
+                        thread.interrupt();
+                        return null;
+                    });
+                }
+            }
+        }
+    }
+
+    /**
+     * Sleeps for just less than the given timeout, in millis.
+     */
+    private static void sleepLessThan(long timeout) throws InterruptedException {
+        int delta = ThreadLocalRandom.current().nextInt(10);
+        Thread.sleep(timeout - delta);
+    }
+}