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Merged
garydgregory merged 1 commit into from
Jul 12, 2026
+105 −10
Merged

Use array element type not basic type for primitive array access #520

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20 changes: 10 additions & 10 deletions src/main/java/org/apache/bcel/verifier/structurals/InstConstraintVisitor.java
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Original file line number Diff line number Diff line change
Expand Up @@ -518,7 +518,7 @@ public void visitDALOAD(final DALOAD o) {
if (!(stack().peek(1) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-top must be of type double[] but is '" + stack().peek(1) + "'.");
}
final Type t = ((ArrayType) stack().peek(1)).getBasicType();
final Type t = ((ArrayType) stack().peek(1)).getElementType();
if (t != Type.DOUBLE) {
constraintViolated(o, "Stack next-to-top must be of type double[] but is '" + stack().peek(1) + "'.");
}
Expand All @@ -539,7 +539,7 @@ public void visitDASTORE(final DASTORE o) {
if (!(stack().peek(2) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-next-to-top must be of type double[] but is '" + stack().peek(2) + "'.");
}
final Type t = ((ArrayType) stack().peek(2)).getBasicType();
final Type t = ((ArrayType) stack().peek(2)).getElementType();
if (t != Type.DOUBLE) {
constraintViolated(o, "Stack next-to-next-to-top must be of type double[] but is '" + stack().peek(2) + "'.");
}
Expand Down Expand Up @@ -825,7 +825,7 @@ public void visitFALOAD(final FALOAD o) {
if (!(stack().peek(1) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-top must be of type float[] but is '" + stack().peek(1) + "'.");
}
final Type t = ((ArrayType) stack().peek(1)).getBasicType();
final Type t = ((ArrayType) stack().peek(1)).getElementType();
if (t != Type.FLOAT) {
constraintViolated(o, "Stack next-to-top must be of type float[] but is '" + stack().peek(1) + "'.");
}
Expand All @@ -846,7 +846,7 @@ public void visitFASTORE(final FASTORE o) {
if (!(stack().peek(2) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-next-to-top must be of type float[] but is '" + stack().peek(2) + "'.");
}
final Type t = ((ArrayType) stack().peek(2)).getBasicType();
final Type t = ((ArrayType) stack().peek(2)).getElementType();
if (t != Type.FLOAT) {
constraintViolated(o, "Stack next-to-next-to-top must be of type float[] but is '" + stack().peek(2) + "'.");
}
Expand Down Expand Up @@ -1199,7 +1199,7 @@ public void visitIALOAD(final IALOAD o) {
if (!(stack().peek(1) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-top must be of type int[] but is '" + stack().peek(1) + "'.");
}
final Type t = ((ArrayType) stack().peek(1)).getBasicType();
final Type t = ((ArrayType) stack().peek(1)).getElementType();
if (t != Type.INT) {
constraintViolated(o, "Stack next-to-top must be of type int[] but is '" + stack().peek(1) + "'.");
}
Expand Down Expand Up @@ -1233,7 +1233,7 @@ public void visitIASTORE(final IASTORE o) {
if (!(stack().peek(2) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-next-to-top must be of type int[] but is '" + stack().peek(2) + "'.");
}
final Type t = ((ArrayType) stack().peek(2)).getBasicType();
final Type t = ((ArrayType) stack().peek(2)).getElementType();
if (t != Type.INT) {
constraintViolated(o, "Stack next-to-next-to-top must be of type int[] but is '" + stack().peek(2) + "'.");
}
Expand Down Expand Up @@ -1970,7 +1970,7 @@ public void visitLALOAD(final LALOAD o) {
if (!(stack().peek(1) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-top must be of type long[] but is '" + stack().peek(1) + "'.");
}
final Type t = ((ArrayType) stack().peek(1)).getBasicType();
final Type t = ((ArrayType) stack().peek(1)).getElementType();
if (t != Type.LONG) {
constraintViolated(o, "Stack next-to-top must be of type long[] but is '" + stack().peek(1) + "'.");
}
Expand Down Expand Up @@ -2004,7 +2004,7 @@ public void visitLASTORE(final LASTORE o) {
if (!(stack().peek(2) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-next-to-top must be of type long[] but is '" + stack().peek(2) + "'.");
}
final Type t = ((ArrayType) stack().peek(2)).getBasicType();
final Type t = ((ArrayType) stack().peek(2)).getElementType();
if (t != Type.LONG) {
constraintViolated(o, "Stack next-to-next-to-top must be of type long[] but is '" + stack().peek(2) + "'.");
}
Expand Down Expand Up @@ -2552,7 +2552,7 @@ public void visitSALOAD(final SALOAD o) {
if (!(stack().peek(1) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-top must be of type short[] but is '" + stack().peek(1) + "'.");
}
final Type t = ((ArrayType) stack().peek(1)).getBasicType();
final Type t = ((ArrayType) stack().peek(1)).getElementType();
if (t != Type.SHORT) {
constraintViolated(o, "Stack next-to-top must be of type short[] but is '" + stack().peek(1) + "'.");
}
Expand All @@ -2573,7 +2573,7 @@ public void visitSASTORE(final SASTORE o) {
if (!(stack().peek(2) instanceof ArrayType)) {
constraintViolated(o, "Stack next-to-next-to-top must be of type short[] but is '" + stack().peek(2) + "'.");
}
final Type t = ((ArrayType) stack().peek(2)).getBasicType();
final Type t = ((ArrayType) stack().peek(2)).getElementType();
if (t != Type.SHORT) {
constraintViolated(o, "Stack next-to-next-to-top must be of type short[] but is '" + stack().peek(2) + "'.");
}
Expand Down
3 changes: 3 additions & 0 deletions src/test/java/org/apache/bcel/verifier/VerifierArrayAccessTest.java
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Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@
import org.apache.bcel.verifier.tests.TestArrayAccess04LongCreator;
import org.apache.bcel.verifier.tests.TestArrayAccess04ShortCreator;
import org.apache.bcel.verifier.tests.TestArrayAccess04UnknownCreator;
import org.apache.bcel.verifier.tests.TestArrayAccess05Creator;
import org.junit.jupiter.api.Test;

class VerifierArrayAccessTest extends AbstractVerifierTest {
Expand All @@ -51,6 +52,8 @@ void testInvalidArrayAccess() throws IOException, ClassNotFoundException {
assertVerifyRejected("TestArrayAccess04Short", "Verification of an arraystore instruction of a short on an array of references must fail.");
final TestArrayAccess04UnknownCreator testArrayAccess04UnknownCreator = new TestArrayAccess04UnknownCreator();
assertThrowsExactly(IllegalArgumentException.class, testArrayAccess04UnknownCreator::create, "Invalid type <unknown object>");
new TestArrayAccess05Creator().create();
assertVerifyRejected("TestArrayAccess05", "Verification of iaload applied to a multidimensional int[][] must fail.");
}

@Test
Expand Down
92 changes: 92 additions & 0 deletions src/test/java/org/apache/bcel/verifier/tests/TestArrayAccess05Creator.java
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Original file line number Diff line number Diff line change
@@ -0,0 +1,92 @@
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/

package org.apache.bcel.verifier.tests;

import static org.junit.jupiter.api.Assertions.assertNotNull;

import java.io.IOException;
import java.io.OutputStream;

import org.apache.bcel.Const;
import org.apache.bcel.generic.ClassGen;
import org.apache.bcel.generic.ConstantPoolGen;
import org.apache.bcel.generic.InstructionConst;
import org.apache.bcel.generic.InstructionFactory;
import org.apache.bcel.generic.InstructionHandle;
import org.apache.bcel.generic.InstructionList;
import org.apache.bcel.generic.MethodGen;
import org.apache.bcel.generic.PUSH;
import org.apache.bcel.generic.Type;

/**
* Emits a method that applies {@code iaload} directly to an {@code int[][]} reference, that is, without first indexing
* into the outer dimension. The component type of {@code int[][]} is {@code int[]} (a reference), so {@code iaload} is
* illegal and structural verification must reject it.
*/
public class TestArrayAccess05Creator extends TestCreator {
private final InstructionFactory factory;
private final ConstantPoolGen cp;
private final ClassGen cg;

public TestArrayAccess05Creator() {
cg = new ClassGen(TEST_PACKAGE + ".TestArrayAccess05", "java.lang.Object", "TestArrayAccess05.java", Const.ACC_PUBLIC | Const.ACC_SUPER,
new String[] {});
cp = cg.getConstantPool();
factory = new InstructionFactory(cg, cp);
}

@Override
public void create(final OutputStream out) throws IOException {
createMethod_0();
createMethod_1();
cg.getJavaClass().dump(out);
}

private void createMethod_0() {
final InstructionList il = new InstructionList();
final MethodGen method = new MethodGen(Const.ACC_PUBLIC, Type.VOID, Type.NO_ARGS, new String[] {}, "<init>", TEST_PACKAGE + ".TestArrayAccess05", il, cp);
il.append(InstructionFactory.createLoad(Type.OBJECT, 0));
il.append(factory.createInvoke("java.lang.Object", "<init>", Type.VOID, Type.NO_ARGS, Const.INVOKESPECIAL));
il.append(InstructionFactory.createReturn(Type.VOID));
method.setMaxStack();
method.setMaxLocals();
cg.addMethod(method.getMethod());
il.dispose();
}

private void createMethod_1() {
final InstructionList il = new InstructionList();
final MethodGen method = new MethodGen(Const.ACC_PUBLIC | Const.ACC_STATIC, Type.VOID, Type.NO_ARGS, new String[] {}, "test",
TEST_PACKAGE + ".TestArrayAccess05", il, cp);

il.append(new PUSH(cp, 1));
il.append(new PUSH(cp, 1));
il.append(factory.createNewArray(Type.INT, (short) 2)); // int[][]
il.append(new PUSH(cp, 0));
il.append(InstructionConst.IALOAD); // iaload on int[][] is illegal
il.append(InstructionConst.POP);
final InstructionHandle ihReturn = il.append(InstructionFactory.createReturn(Type.VOID));
assertNotNull(ihReturn);
method.setMaxStack();
method.setMaxLocals();
cg.addMethod(method.getMethod());
il.dispose();
}
}
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