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/micro/org/openjdk/bench/java/lang/ClassLoaderDefineClass.java
+++ b/test/micro/org/openjdk/bench/java/lang/ClassLoaderDefineClass.java
@ -0,0 +1,115 @@
+/*
+ * 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.
+ */
+package org.openjdk.bench.java.lang;
+
+import org.openjdk.jmh.annotations.Benchmark;
+import org.openjdk.jmh.annotations.BenchmarkMode;
+import org.openjdk.jmh.annotations.Fork;
+import org.openjdk.jmh.annotations.Level;
+import org.openjdk.jmh.annotations.Measurement;
+import org.openjdk.jmh.annotations.Mode;
+import org.openjdk.jmh.annotations.OutputTimeUnit;
+import org.openjdk.jmh.annotations.Scope;
+import org.openjdk.jmh.annotations.Setup;
+import org.openjdk.jmh.annotations.State;
+import org.openjdk.jmh.annotations.Warmup;
+import org.openjdk.jmh.infra.Blackhole;
+
+import java.lang.foreign.Arena;
+import java.nio.ByteBuffer;
+import java.util.concurrent.TimeUnit;
+import java.util.HexFormat;
+
+/**
+ * Tests java.lang.ClassLoader.defineClass(ByteBuffer)
+ */
+@BenchmarkMode(Mode.AverageTime)
+@OutputTimeUnit(TimeUnit.NANOSECONDS)
+@State(Scope.Thread)
+@Warmup(iterations = 5, time = 1)
+@Measurement(iterations = 5, time = 1)
+@Fork(3)
+public class ClassLoaderDefineClass {
+
+    private byte[] classBytes;
+    private ByteBuffer directBuffer;
+    private ByteBuffer heapBuffer;
+
+    @Setup(Level.Iteration)
+    public void setup() throws Exception {
+        classBytes = getTestClassBytes();
+        directBuffer = Arena.ofConfined()
+            .allocate(classBytes.length)
+            .asByteBuffer()
+            .put(classBytes)
+            .flip();
+        heapBuffer = ByteBuffer.wrap(classBytes);
+    }
+
+    @Benchmark
+    public void testDefineClassByteBufferHeap(Blackhole bh) throws Exception {
+        bh.consume(new DummyClassLoader().defineClassFromHeapBuffer(heapBuffer));
+    }
+
+    @Benchmark
+    public void testDefineClassByteBufferDirect(Blackhole bh) throws Exception {
+        bh.consume(new DummyClassLoader().defineClassFromDirectBuffer(directBuffer));
+    }
+
+    private static final class DummyClassLoader extends ClassLoader {
+
+        Class<?> defineClassFromHeapBuffer(ByteBuffer bb) throws Exception {
+            bb.rewind();
+            return defineClass(null, bb, null);
+        }
+
+        Class<?> defineClassFromDirectBuffer(ByteBuffer bb) throws Exception {
+            bb.rewind();
+            return defineClass(null, bb, null);
+        }
+    }
+
+    private static byte[] getTestClassBytes() throws Exception {
+        final String source = """
+        public class Greeting {
+            public String hello() {
+                return "Hello";
+            }
+        }
+        """;
+        // (externally) compiled content of the above source, represented as hex
+        final String classBytesHex = """
+        cafebabe0000004600110a000200030700040c000500060100106a617661
+        2f6c616e672f4f626a6563740100063c696e69743e010003282956080008
+        01000548656c6c6f07000a0100084772656574696e67010004436f646501
+        000f4c696e654e756d6265725461626c6501000568656c6c6f0100142829
+        4c6a6176612f6c616e672f537472696e673b01000a536f7572636546696c
+        6501000d4772656574696e672e6a61766100210009000200000000000200
+        01000500060001000b0000001d00010001000000052ab70001b100000001
+        000c000000060001000000010001000d000e0001000b0000001b00010001
+        000000031207b000000001000c000000060001000000030001000f000000
+        020010
+        """;
+        return HexFormat.of().parseHex(classBytesHex.replaceAll("\n", ""));
+    }
+}