提交 dc1b8385 编写于 作者: K ksrini

6567415: Neverending loop in ClassReader

Reviewed-by: jjg
上级 49eda07a
/*
* Copyright (c) 1999, 2009, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 1999, 2010, 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
......@@ -77,6 +77,8 @@ public class ClassReader implements Completer {
protected static final Context.Key<ClassReader> classReaderKey =
new Context.Key<ClassReader>();
public static final int INITIAL_BUFFER_SIZE = 0x0fff0;
Annotate annotate;
/** Switch: verbose output.
......@@ -185,7 +187,7 @@ public class ClassReader implements Completer {
/** The buffer containing the currently read class file.
*/
byte[] buf = new byte[0x0fff0];
byte[] buf = new byte[INITIAL_BUFFER_SIZE];
/** The current input pointer.
*/
......@@ -2419,8 +2421,14 @@ public class ClassReader implements Completer {
}
}
}
/*
* ensureCapacity will increase the buffer as needed, taking note that
* the new buffer will always be greater than the needed and never
* exactly equal to the needed size or bp. If equal then the read (above)
* will infinitely loop as buf.length - bp == 0.
*/
private static byte[] ensureCapacity(byte[] buf, int needed) {
if (buf.length < needed) {
if (buf.length <= needed) {
byte[] old = buf;
buf = new byte[Integer.highestOneBit(needed) << 1];
System.arraycopy(old, 0, buf, 0, old.length);
......
/*
* Copyright (c) 2010, 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.
*/
/*
* @test
* @bug 6567415
* @summary Test to ensure javac does not go into an infinite loop, while
* reading a classfile of a specific length.
* @compile -XDignore.symbol.file T6567415.java
* @run main T6567415
* @author ksrini
*/
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
/*
* this test compiles Bar.java into a classfile and enlarges the file to the
* magic file length, then use this mutated file on the classpath to compile
* Foo.java which references Bar.java and Ka-boom. QED.
*/
public class T6567415 {
final static String TEST_FILE_NAME = "Bar";
final static String TEST_JAVA = TEST_FILE_NAME + ".java";
final static String TEST_CLASS = TEST_FILE_NAME + ".class";
final static String TEST2_FILE_NAME = "Foo";
final static String TEST2_JAVA = TEST2_FILE_NAME + ".java";
/*
* the following is the initial buffer length set in ClassReader.java
* thus this value needs to change if ClassReader buf length changes.
*/
final static int BAD_FILE_LENGTH =
com.sun.tools.javac.jvm.ClassReader.INITIAL_BUFFER_SIZE;
static void createClassFile() throws IOException {
FileOutputStream fos = null;
try {
fos = new FileOutputStream(TEST_JAVA);
PrintStream ps = new PrintStream(fos);
ps.println("public class " + TEST_FILE_NAME + " {}");
} finally {
fos.close();
}
String cmds[] = {TEST_JAVA};
com.sun.tools.javac.Main.compile(cmds);
}
static void enlargeClassFile() throws IOException {
File f = new File(TEST_CLASS);
if (!f.exists()) {
System.out.println("file not found: " + TEST_CLASS);
System.exit(1);
}
File tfile = new File(f.getAbsolutePath() + ".tmp");
f.renameTo(tfile);
RandomAccessFile raf = null;
FileChannel wfc = null;
FileInputStream fis = null;
FileChannel rfc = null;
try {
raf = new RandomAccessFile(f, "rw");
wfc = raf.getChannel();
fis = new FileInputStream(tfile);
rfc = fis.getChannel();
ByteBuffer bb = MappedByteBuffer.allocate(BAD_FILE_LENGTH);
rfc.read(bb);
bb.rewind();
wfc.write(bb);
wfc.truncate(BAD_FILE_LENGTH);
} finally {
wfc.close();
raf.close();
rfc.close();
fis.close();
}
System.out.println("file length = " + f.length());
}
static void createJavaFile() throws IOException {
FileOutputStream fos = null;
try {
fos = new FileOutputStream(TEST2_JAVA);
PrintStream ps = new PrintStream(fos);
ps.println("public class " + TEST2_FILE_NAME +
" {" + TEST_FILE_NAME + " b = new " +
TEST_FILE_NAME + " ();}");
} finally {
fos.close();
}
}
public static void main(String... args) throws Exception {
createClassFile();
enlargeClassFile();
createJavaFile();
Thread t = new Thread () {
@Override
public void run() {
String cmds[] = {"-verbose", "-cp", ".", TEST2_JAVA};
int ret = com.sun.tools.javac.Main.compile(cmds);
System.out.println("test compilation returns: " + ret);
}
};
t.start();
t.join(1000*10);
System.out.println(t.getState());
if (t.isAlive()) {
throw new RuntimeException("Error: compilation is looping");
}
}
}
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册