Bug 538636 - disable javaagent based on Object.class major_version
... also upgraded to ASM 6.2.1 (see bug 539082)
Change-Id: I5fe1457929f8d6416a6f0434ee8414eb177eef8e
Signed-off-by: Igor Fedorenko <igor@ifedorenko.com>
diff --git a/org.eclipse.jdt.launching.javaagent/pom.xml b/org.eclipse.jdt.launching.javaagent/pom.xml
index 5b0334b..74756ff 100644
--- a/org.eclipse.jdt.launching.javaagent/pom.xml
+++ b/org.eclipse.jdt.launching.javaagent/pom.xml
@@ -20,7 +20,7 @@
<dependency>
<groupId>org.ow2.asm</groupId>
<artifactId>asm</artifactId>
- <version>6.2</version>
+ <version>6.2.1</version>
</dependency>
</dependencies>
diff --git a/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/javaagent/Premain.java b/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/javaagent/Premain.java
index 8b38b6a..225df81 100644
--- a/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/javaagent/Premain.java
+++ b/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/javaagent/Premain.java
@@ -13,6 +13,7 @@
*******************************************************************************/
package org.eclipse.jdt.launching.internal.javaagent;
+import java.io.IOException;
import java.io.InputStream;
import java.lang.instrument.ClassFileTransformer;
import java.lang.instrument.IllegalClassFormatException;
@@ -22,7 +23,6 @@
import java.security.ProtectionDomain;
import org.eclipse.jdt.launching.internal.weaving.ClassfileTransformer;
-import org.objectweb.asm.ClassReader;
public class Premain {
private static final ClassfileTransformer transformer = new ClassfileTransformer();
@@ -30,23 +30,12 @@
public static void premain(final String agentArgs, final Instrumentation inst) {
final boolean debuglog = "debuglog".equals(agentArgs); //$NON-NLS-1$
- // disable instrumentation if ASM is not able to read Object.class definition
- try {
- InputStream is = ClassLoader.getSystemResourceAsStream("java/lang/Object.class"); //$NON-NLS-1$
- try {
- new ClassReader(is);
- }
- finally {
- is.close();
- }
- }
- catch (Exception e) {
+ // disable instrumentation if Object.class class format is not supported
+ short major = readJavaLangObjectMajor(debuglog);
+ if (major < 0 || major > ClassfileTransformer.MAX_CLASS_MAJOR) {
String vendor = System.getProperty("java.vendor"); //$NON-NLS-1$
String version = System.getProperty("java.version"); //$NON-NLS-1$
- System.err.printf("JRE %s/%s is not supported, advanced source lookup disabled: %s.\n", vendor, version, e.getMessage()); //$NON-NLS-1$
- if (debuglog) {
- e.printStackTrace(System.err);
- }
+ System.err.printf("JRE %s/%s is not supported, advanced source lookup disabled.\n", vendor, version); //$NON-NLS-1$
return;
}
@@ -89,4 +78,52 @@
System.err.println("Advanced source lookup enabled."); //$NON-NLS-1$
}
}
+
+ private static short readJavaLangObjectMajor(boolean debuglog) {
+ // https://docs.oracle.com/javase/specs/jvms/se10/html/jvms-4.html
+ // We need class major_version, i.e. the u2 field starting at offset 6
+
+ final int offset = 6;
+
+ final InputStream is = ClassLoader.getSystemResourceAsStream("java/lang/Object.class"); //$NON-NLS-1$
+ if (is == null) {
+ if (debuglog) {
+ System.err.println("Could not open java/lang/Object.class system resource stream."); //$NON-NLS-1$
+ }
+ return -1;
+ }
+
+ byte[] bytes = new byte[offset + 2];
+ try {
+ try {
+ if (is.read(bytes) < bytes.length) {
+ if (debuglog) {
+ System.err.println("Could not read java/lang/Object.class system resource stream."); //$NON-NLS-1$
+ }
+ return -1;
+ }
+ }
+ finally {
+ is.close();
+ }
+ }
+ catch (IOException e) {
+ if (debuglog) {
+ System.err.println("Could not read java/lang/Object.class system resource stream."); //$NON-NLS-1$
+ e.printStackTrace(System.err);
+ }
+ return -1;
+ }
+
+ int magic = ((bytes[0] & 0xFF) << 24) | ((bytes[1] & 0xFF) << 16) | ((bytes[2] & 0xFF) << 8) | (bytes[3] & 0xFF);
+ if (magic != 0xCAFEBABE) {
+ if (debuglog) {
+ System.err.println("Invalid java/lang/Object.class magic."); //$NON-NLS-1$
+ }
+ return -1;
+ }
+
+ return (short) (((bytes[offset] & 0xFF) << 8) | (bytes[offset + 1] & 0xFF));
+ }
+
}
diff --git a/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/weaving/ClassfileTransformer.java b/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/weaving/ClassfileTransformer.java
index cd163e3..6476bba 100644
--- a/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/weaving/ClassfileTransformer.java
+++ b/org.eclipse.jdt.launching.javaagent/src/main/java/org/eclipse/jdt/launching/internal/weaving/ClassfileTransformer.java
@@ -23,12 +23,18 @@
// must match JDIHelpers.STRATA_ID
private static final String STRATA_ID = "jdt"; //$NON-NLS-1$
+ /** max supported java class format major version, must match {@link #ASM_API} below **/
+ public static final int MAX_CLASS_MAJOR = Opcodes.V10;
+
+ /** supported ASM API version, must match {@link #MAX_CLASS_MAJOR} above */
+ private static final int ASM_API = Opcodes.ASM6;
+
public byte[] transform(byte[] classfileBuffer, final String location) {
final ClassReader r = new ClassReader(classfileBuffer, 0, classfileBuffer.length);
final ClassWriter w = new ClassWriter(0);
- r.accept(new ClassVisitor(Opcodes.ASM5, w) {
+ r.accept(new ClassVisitor(ASM_API, w) {
@Override
public void visitSource(String source, String debug) {
String javaSource = source;
diff --git a/org.eclipse.jdt.launching/lib/javaagent-shaded.jar b/org.eclipse.jdt.launching/lib/javaagent-shaded.jar
index 42c65f3..647041f 100644
--- a/org.eclipse.jdt.launching/lib/javaagent-shaded.jar
+++ b/org.eclipse.jdt.launching/lib/javaagent-shaded.jar
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