jdk/test/hotspot/jtreg/runtime/classFileParserBug/StackMapTooLong.java

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/*
 * @test Very large StackMapTable should cause OutOfMemoryError and not VM crash.
 * @bug 8386562
 * @library /test/lib /test/hotspot/jtreg/testlibrary/asm
 * @run main StackMapTooLong
 */

import java.lang.invoke.MethodHandles;
import static org.objectweb.asm.Opcodes.*;
import org.objectweb.asm.*;

public class StackMapTooLong {
    private static String BadClass = "BadClass";

    public static void main(String[] args) throws Exception {
        byte[] classFile = dumpBadClass();

        try {
            MethodHandles.lookup().defineClass(classFile);
            throw new RuntimeException("OutOfMemoryError expected but not thrown!");
        } catch (OutOfMemoryError expected) {}
    }

    static class LargeStackMapTable extends Attribute {
        LargeStackMapTable() {
            super("StackMapTable");
        }

        @Override
        public boolean isCodeAttribute() {
            return true;
        }

        @Override
        protected ByteVector write(ClassWriter cw, byte[] code,
                                   int codeLength, int maxStack, int maxLocals) {
            int len = 16 * 1024 * 1024 + 1; // Too large to be allocated by Metaspace::allocate()
            ByteVector bv = new ByteVector();
            bv.putByteArray(new byte[len], 0, len);
            return bv;
        }
    }

    private static byte[] dumpBadClass() throws Exception {
        ClassWriter classWriter = new ClassWriter(0);
        MethodVisitor methodVisitor;

        classWriter.visit(51, ACC_SUPER, BadClass, null, "java/lang/Object",
                          null);

        {
            methodVisitor =
                classWriter.visitMethod(ACC_PUBLIC | ACC_STATIC, "main",
                                        "([Ljava/lang/String;)V", null, null);
            methodVisitor.visitCode();
            methodVisitor.visitInsn(RETURN);
            methodVisitor.visitAttribute(new LargeStackMapTable());
            methodVisitor.visitMaxs(0, 1);
            methodVisitor.visitEnd();
        }
        classWriter.visitEnd();

        return classWriter.toByteArray();
    }
}