1 /*
2 * Copyright (c) 2014, 2015, 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 * @test
26 * @bug 8042235
27 * @summary redefining method used by multiple MethodHandles crashes VM
28 * @modules java.base/jdk.internal.org.objectweb.asm
29 * java.compiler
30 * java.instrument
31 * java.management
32 * @compile -XDignore.symbol.file RedefineMethodUsedByMultipleMethodHandles.java
33 * @run main/othervm RedefineMethodUsedByMultipleMethodHandles
34 */
35
36 import java.io.*;
37 import java.lang.instrument.*;
38 import java.lang.invoke.*;
39 import java.lang.invoke.MethodHandles.Lookup;
40 import java.lang.management.*;
41 import java.lang.reflect.*;
42 import java.nio.file.*;
43 import java.security.*;
44 import java.util.jar.*;
45
46 import javax.tools.*;
47
48 import jdk.internal.org.objectweb.asm.*;
49
50 public class RedefineMethodUsedByMultipleMethodHandles {
51
52 static class Foo {
53 public static Object getName() {
54 return "foo";
55 }
56 }
57
58 public static void main(String[] args) throws Throwable {
59
60 Lookup lookup = MethodHandles.lookup();
61 Method fooMethod = Foo.class.getDeclaredMethod("getName");
62
63 // fooMH2 displaces fooMH1 from the MemberNamesTable
64 MethodHandle fooMH1 = lookup.unreflect(fooMethod);
65 MethodHandle fooMH2 = lookup.unreflect(fooMethod);
66
67 System.out.println("fooMH1.invoke = " + fooMH1.invokeExact());
68 System.out.println("fooMH2.invoke = " + fooMH2.invokeExact());
69
70 // Redefining Foo.getName() causes vmtarget to be updated
71 // in fooMH2 but not fooMH1
72 redefineFoo();
73
74 // Full GC causes fooMH1.vmtarget to be deallocated
75 System.gc();
76
77 // Calling fooMH1.vmtarget crashes the VM
78 System.out.println("fooMH1.invoke = " + fooMH1.invokeExact());
79 }
80
81 /**
82 * Adds the class file bytes for {@code c} to {@code jar}.
83 */
84 static void add(JarOutputStream jar, Class<?> c) throws IOException {
85 String classAsPath = c.getName().replace('.', '/') + ".class";
86 jar.putNextEntry(new JarEntry(classAsPath));
87 InputStream stream = c.getClassLoader().getResourceAsStream(classAsPath);
88
89 int b;
90 while ((b = stream.read()) != -1) {
91 jar.write(b);
92 }
93 }
94
95 static void redefineFoo() throws Exception {
96 Manifest manifest = new Manifest();
97 manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
98 Attributes mainAttrs = manifest.getMainAttributes();
99 mainAttrs.putValue("Agent-Class", FooAgent.class.getName());
100 mainAttrs.putValue("Can-Redefine-Classes", "true");
101 mainAttrs.putValue("Can-Retransform-Classes", "true");
102
103 Path jar = Files.createTempFile("myagent", ".jar");
104 try {
105 JarOutputStream jarStream = new JarOutputStream(new FileOutputStream(jar.toFile()), manifest);
106 add(jarStream, FooAgent.class);
107 add(jarStream, FooTransformer.class);
108 jarStream.close();
109 runAgent(jar);
110 } finally {
111 Files.deleteIfExists(jar);
112 }
113 }
114
115 public static void runAgent(Path agent) throws Exception {
116 String vmName = ManagementFactory.getRuntimeMXBean().getName();
117 int p = vmName.indexOf('@');
118 assert p != -1 : "VM name not in <pid>@<host> format: " + vmName;
119 String pid = vmName.substring(0, p);
120 ClassLoader cl = ToolProvider.getSystemToolClassLoader();
121 Class<?> c = Class.forName("com.sun.tools.attach.VirtualMachine", true, cl);
122 Method attach = c.getDeclaredMethod("attach", String.class);
123 Method loadAgent = c.getDeclaredMethod("loadAgent", String.class);
124 Method detach = c.getDeclaredMethod("detach");
125 Object vm = attach.invoke(null, pid);
126 loadAgent.invoke(vm, agent.toString());
127 detach.invoke(vm);
128 }
129
130 public static class FooAgent {
131
132 public static void agentmain(@SuppressWarnings("unused") String args, Instrumentation inst) throws Exception {
133 assert inst.isRedefineClassesSupported();
134 assert inst.isRetransformClassesSupported();
135 inst.addTransformer(new FooTransformer(), true);
136 Class<?>[] classes = inst.getAllLoadedClasses();
137 for (int i = 0; i < classes.length; i++) {
138 Class<?> c = classes[i];
139 if (c == Foo.class) {
140 inst.retransformClasses(new Class[]{c});
141 }
142 }
143 }
144 }
145
146 static class FooTransformer implements ClassFileTransformer {
147
148 @Override
149 public byte[] transform(ClassLoader cl, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws IllegalClassFormatException {
150 if (Foo.class.equals(classBeingRedefined)) {
151 System.out.println("redefining " + classBeingRedefined);
152 ClassReader cr = new ClassReader(classfileBuffer);
153 ClassWriter cw = new ClassWriter(cr, ClassWriter.COMPUTE_FRAMES);
154 ClassVisitor adapter = new ClassVisitor(Opcodes.ASM5, cw) {
155 @Override
156 public MethodVisitor visitMethod(int access, String base, String desc, String signature, String[] exceptions) {
157 MethodVisitor mv = cv.visitMethod(access, base, desc, signature, exceptions);
158 if (mv != null) {
159 mv = new MethodVisitor(Opcodes.ASM5, mv) {
160 @Override
161 public void visitLdcInsn(Object cst) {
162 System.out.println("replacing \"" + cst + "\" with \"bar\"");
163 mv.visitLdcInsn("bar");
164 }
165 };
166 }
167 return mv;
168 }
169 };
170
171 cr.accept(adapter, ClassReader.SKIP_FRAMES);
172 cw.visitEnd();
173 return cw.toByteArray();
174 }
175 return classfileBuffer;
176 }
177 }
178 }