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/cds/appcds/aotCache/JavaAgentTransformer.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2025, 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.System.Logger.Level;
+import java.lang.instrument.ClassFileTransformer;
+import java.lang.instrument.IllegalClassFormatException;
+import java.lang.instrument.Instrumentation;
+import java.security.ProtectionDomain;
+
+// This class is available on the classpath so it can be accessed by JavaAgentApp
+public class JavaAgentTransformer  implements ClassFileTransformer {
+    private static Instrumentation savedInstrumentation;
+    private static final System.Logger LOGGER = System.getLogger(JavaAgentTransformer.class.getName());
+
+    public static void premain(String agentArguments, Instrumentation instrumentation) {
+        System.out.println("JavaAgentTransformer.premain() is called");
+        instrumentation.addTransformer(new JavaAgentTransformer(), /*canRetransform=*/true);
+        savedInstrumentation = instrumentation;
+
+        LOGGER.log(Level.WARNING, "JavaAgentTransformer::premain() is finished");
+    }
+
+    public static Instrumentation getInstrumentation() {
+        return savedInstrumentation;
+    }
+
+    public static void agentmain(String args, Instrumentation inst) throws Exception {
+        premain(args, inst);
+    }
+
+    public byte[] transform(ClassLoader loader, String name, Class<?> classBeingRedefined,
+                            ProtectionDomain pd, byte[] buffer) throws IllegalClassFormatException {
+        if (name.equals("JavaAgentApp$ShouldBeTransformed")) {
+            System.out.println("Transforming: " + name + "; Class<?> = " + classBeingRedefined);
+            try {
+                replace(buffer, "XXXX", "YYYY");
+            } catch (Throwable t) {
+                t.printStackTrace();
+            }
+            Thread.dumpStack();
+            return buffer;
+        }
+        return null;
+    }
+
+    static void replace(byte[] buffer, String from, String to) {
+        int n = Util.replace(buffer, from, to);
+        System.out.println("..... replaced " + n + " occurrence(s) of '" + from + "' to '" + to + "'");
+    }
+}