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.
2026-03-26 17:11:57 -04:00 · 2026-03-26 17:11:57 -04:00 · 0a580b313d
commit 0a580b313d
70422 changed files with 17213626 additions and 0 deletions
--- a/test/jdk/java/lang/Thread/jni/AttachCurrentThread/ImplicitAttach.java
+++ b/test/jdk/java/lang/Thread/jni/AttachCurrentThread/ImplicitAttach.java
@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2022, 2023, 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.lang.foreign.*;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.util.concurrent.CountDownLatch;
+
+/**
+ * Test native threads attaching implicitly to the VM by means of an upcall.
+ */
+public class ImplicitAttach {
+    private static final ValueLayout.OfInt C_INT = ValueLayout.JAVA_INT;
+    private static final AddressLayout C_POINTER = ValueLayout.ADDRESS;
+
+    private static volatile CountDownLatch latch;
+
+    public static void main(String[] args) throws Throwable {
+        int threadCount;
+        if (args.length > 0) {
+            threadCount = Integer.parseInt(args[0]);
+        } else {
+            threadCount = 2;
+        }
+        latch = new CountDownLatch(threadCount);
+
+        Linker abi;
+        try {
+            abi = Linker.nativeLinker();
+        } catch (UnsupportedOperationException e) {
+            System.out.println("Test skipped, no native linker on this platform");
+            return;
+        }
+
+        // stub to invoke callback
+        MethodHandle callback = MethodHandles.lookup()
+                .findStatic(ImplicitAttach.class, "callback", MethodType.methodType(void.class));
+        MemorySegment upcallStub = abi.upcallStub(callback,
+                FunctionDescriptor.ofVoid(),
+                Arena.global());
+
+        // void start_threads(int count, void *(*f)(void *))
+        SymbolLookup symbolLookup = SymbolLookup.loaderLookup();
+        MemorySegment symbol = symbolLookup.find("start_threads").orElseThrow();
+        FunctionDescriptor desc = FunctionDescriptor.ofVoid(C_INT, C_POINTER);
+        MethodHandle start_threads = abi.downcallHandle(symbol, desc);
+
+        // start the threads and wait for the threads to call home
+        start_threads.invoke(threadCount, upcallStub);
+        latch.await();
+    }
+
+    /**
+     * Invoked from native thread.
+     */
+    private static void callback() {
+        System.out.println(Thread.currentThread());
+        latch.countDown();
+    }
+
+    static {
+        System.loadLibrary("ImplicitAttach");
+    }
+}