1 /* 2 * Copyright (c) 2010, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24 25 /* 26 * @test 27 * @modules java.base/jdk.internal.misc 28 * 29 * @summary converted from VM Testbase vm/mlvm/anonloader/stress/byteMutation. 30 * VM Testbase keywords: [feature_mlvm, nonconcurrent] 31 * 32 * @library /vmTestbase 33 * /test/lib 34 * @run driver jdk.test.lib.FileInstaller . . 35 * 36 * @comment build test class and indify classes 37 * @build vm.mlvm.anonloader.stress.byteMutation.Test 38 * @run driver vm.mlvm.share.IndifiedClassesBuilder 39 * 40 * @run main/othervm vm.mlvm.anonloader.stress.byteMutation.Test -stressIterationsFactor 100000 41 */ 42 43 package vm.mlvm.anonloader.stress.byteMutation; 44 45 import vm.mlvm.anonloader.share.AnonkTestee01; 46 import vm.mlvm.anonloader.share.StressClassLoadingTest; 47 import vm.share.FileUtils; 48 import vm.share.options.Option; 49 50 /** 51 * The test does the following in a cycle: 52 * 53 * <ol> 54 * <li>Takes bytes from a valid class file 55 * <li>Sets 1 to 5 bytes in random positions to random values 56 * <li>Tries to load such class using: 57 * <ul> 58 * <li>a custom class loader, 59 * <li>{@link sun.misc.Unsafe#defineAnonymousClass} 60 * when {@code -unsafeLoad true} option is passed to the test. 61 * </ul> 62 * </ol> 63 * 64 * <p>In most cases the resulting class file is invalid and rejected by 65 * the VM verifier. But this test tries to find pathological cases, such 66 * as infinite loops during verification or VM crashes. 67 * 68 * <p>NB: There is a tool to load invalid classes saved by this test. 69 * Please see tool documentation at {@link vm.mlvm.tools.LoadClass} 70 * 71 */ 72 public class Test extends StressClassLoadingTest { 73 private final static Class<?> HOST_CLASS = AnonkTestee01.class; 74 private final byte[] testeeBytes; 75 @Option(name = "mutationCount", default_value = "3", 76 description = "How many bytes to mutate in a class") 77 private int mutationCount = 3; 78 79 /** 80 * Constructs the test. 81 * @throws Exception if there are any errors when 82 * reading {@link vm.mlvm.anonloader.share.AnonkTestee01} class bytecodes. 83 */ 84 public Test() throws Exception { 85 this.testeeBytes = FileUtils.readClass(AnonkTestee01.class.getName()); 86 } 87 88 /** 89 * Returns {@link vm.mlvm.anonloader.share.AnonkTestee01} class to the 90 * parent. 91 * @return {@link vm.mlvm.anonloader.share.AnonkTestee01} class. 92 */ 93 @Override 94 protected Class<?> getHostClass() { 95 return HOST_CLASS; 96 } 97 98 /** 99 * Takes {@link vm.mlvm.anonloader.share.AnonkTestee01} class bytecodes 100 * and modifies mutationCount bytes setting them to random values. 101 * @return {@link vm.mlvm.anonloader.share.AnonkTestee01} class bytecodes with modified bytes. 102 */ 103 @Override 104 protected byte[] generateClassBytes() { 105 // TODO: there is non-zero probability that generated bytecode will be 106 // valid, so it should be a subject of fuzzing mechanism 107 byte[] alteredBytes = testeeBytes.clone(); 108 for (int j = 0; j < mutationCount; ++j) { 109 alteredBytes[getRNG().nextInt(alteredBytes.length)] = (byte) getRNG().nextInt(256); 110 } 111 return alteredBytes; 112 } 113 114 /** 115 * Runs the test. 116 * @param args Test arguments. 117 */ 118 public static void main(String[] args) { 119 StressClassLoadingTest.launch(args); 120 } 121 }