Merge pull request #18130 from theresa-m/nr_verification_4

NullRestricted field throws NPE on null assignment in withfield
eclipse-openj9 · Sep 14, 2023 · c53da53 · c53da53
2 parents 754717a + 3f5b896
commit c53da53
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Showing 3 changed files with 57 additions and 6 deletions.
diff --git a/runtime/vm/BytecodeInterpreter.hpp b/runtime/vm/BytecodeInterpreter.hpp
@@ -9697,6 +9697,16 @@ class INTERPRETER_CLASS
 				goto done;
 			}
 
+#if defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES)
+			if (J9_ARE_ALL_BITS_SET(flags, J9FieldFlagIsNullRestricted)) {
+				j9object_t valueref = *(j9object_t*)_sp;
+				if (NULL == valueref) {
+					rc = THROW_NPE;
+					goto done;
+				}
+			}
+#endif /* defined(J9VM_OPT_VALHALLA_FLATTENABLE_VALUE_TYPES) */
+
 			/* need to zero memset the memory so padding bytes are zeroed for memcmp-like comparisons */
 			copyObjectRef = VM_ValueTypeHelpers::cloneValueType(_currentThread, _objectAccessBarrier, _objectAllocate, objectRefClass, originalObjectRef, true);
 			if (NULL == copyObjectRef) {

diff --git a/test/functional/Valhalla/src/org/openj9/test/lworld/ValhallaAttributeGenerator.java b/test/functional/Valhalla/src/org/openj9/test/lworld/ValhallaAttributeGenerator.java
@@ -88,7 +88,7 @@ public static Class<?> generateNullRestrictedAttributeInArrayField(String classN
 		return generator.defineClass(className, classBytes, 0, classBytes.length);
 	}
 
-	public static Class<?> generateStaticNullRestrictedFieldAssignedToNull(String className, String fieldClassName) {
+	public static Class<?> generatePutStaticNullToNullRestrictedField(String className, String fieldClassName) {
 		String fieldName = "field";
 
 		/* Generate field class - value class with ImplicitCreation attribute and ACC_DEFAULT flag set.  */
@@ -126,7 +126,7 @@ public static Class<?> generateStaticNullRestrictedFieldAssignedToNull(String cl
 		return generator.defineClass(className, classBytes, 0, classBytes.length);
 	}
 
-	public static Class<?> generateInstanceNullRestrictedFieldAssignedToNull(String className, String fieldClassName) {
+	public static Class<?> generatePutFieldNullToNullRestrictedField(String className, String fieldClassName) {
 		String fieldName = "field";
 
 		/* Generate field class - value class with ImplicitCreation attribute and ACC_DEFAULT flag set.  */
@@ -158,6 +158,41 @@ public static Class<?> generateInstanceNullRestrictedFieldAssignedToNull(String
 		return generator.defineClass(className, classBytes, 0, classBytes.length);
 	}
 
+	public static Class<?> generateWithFieldStoreNullToNullRestrictedField(String className, String fieldClassName) {
+		String fieldName = "field";
+
+		/* Generate field class - value class with ImplicitCreation attribute and ACC_DEFAULT flag set.  */
+		byte[] fieldClassBytes = generateClass(fieldClassName, ACC_PUBLIC + ACC_FINAL + ValhallaUtils.ACC_VALUE_TYPE,
+			new Attribute[] {new ImplicitCreationAttribute(ValhallaUtils.ACC_DEFAULT)});
+		Class<?> fieldClass = generator.defineClass(fieldClassName, fieldClassBytes, 0, fieldClassBytes.length);
+
+		ClassWriter classWriter = new ClassWriter(0);
+		classWriter.visit(ValhallaUtils.CLASS_FILE_MAJOR_VERSION, ACC_PUBLIC + ValhallaUtils.ACC_IDENTITY, className, null, "java/lang/Object", null);
+
+		/* instance field of previously generated field class with NullRestrictd attribute */
+		FieldVisitor fieldVisitor = classWriter.visitField(ACC_PUBLIC, fieldName, fieldClass.descriptorString(), null, null);
+		fieldVisitor.visitAttribute(new NullRestrictedAttribute());
+
+		MethodVisitor mvInit = classWriter.visitMethod(ACC_PUBLIC, "<init>", "()V", null, null);
+		mvInit.visitCode();
+		mvInit.visitVarInsn(ALOAD, 0);
+		mvInit.visitMethodInsn(INVOKESPECIAL, "java/lang/Object", "<init>", "()V");
+		mvInit.visitVarInsn(ALOAD, 0);
+		mvInit.visitTypeInsn(ValhallaUtils.ACONST_INIT, fieldClass.descriptorString());
+		mvInit.visitFieldInsn(PUTFIELD, className, fieldName, fieldClass.descriptorString());
+		mvInit.visitVarInsn(ALOAD, 0);
+		mvInit.visitFieldInsn(GETFIELD, className, fieldName, fieldClass.descriptorString());
+		mvInit.visitInsn(ACONST_NULL);
+		mvInit.visitFieldInsn(ValhallaUtils.WITHFIELD, className, fieldName, fieldClass.descriptorString());
+		mvInit.visitInsn(RETURN);
+		mvInit.visitMaxs(2, 1);
+		mvInit.visitEnd();
+
+		classWriter.visitEnd();
+		byte[] classBytes = classWriter.toByteArray();
+		return generator.defineClass(className, classBytes, 0, classBytes.length);
+	}
+
 	public static Class<?> findLoadedTestClass(String name) {
 		return generator.findLoadedClass(name);
 	}

diff --git a/test/functional/Valhalla/src/org/openj9/test/lworld/ValhallaAttributeTests.java b/test/functional/Valhalla/src/org/openj9/test/lworld/ValhallaAttributeTests.java
@@ -105,8 +105,8 @@ static public void testNullRestrictedNotAllowedInArrayTypeField() throws Throwab
 
 	/* Instance field with NullRestricted attribute cannot be set to null. */
 	@Test(expectedExceptions = java.lang.NullPointerException.class)
-	static public void testNullRestrictedInstanceFieldCannotBeAssignedNull() throws Throwable {
-		Class<?> c = ValhallaAttributeGenerator.generateInstanceNullRestrictedFieldAssignedToNull("TestNullRestrictedInstanceFieldCannotBeAssignedNull", "TestNullRestrictedInstanceFieldCannotBeAssignedNullField");
+	static public void testPutFieldNullToNullRestrictedField() throws Throwable {
+		Class<?> c = ValhallaAttributeGenerator.generatePutFieldNullToNullRestrictedField("TestPutFieldNullToNullRestrictedField", "TestPutFieldNullToNullRestrictedFieldField");
 		c.newInstance();
 	}
 
@@ -117,9 +117,9 @@ static public void testNullRestrictedInstanceFieldCannotBeAssignedNull() throws
 	 * Since value fields are implicitly final this will always be the case.
 	 */
 	@Test
-	static public void testNullRestrictedStaticFieldCannotBeAssignedNull() throws Throwable {
+	static public void testPutStaticNullToNullRestrictedField() throws Throwable {
 		try {
-			Class<?> c = ValhallaAttributeGenerator.generateStaticNullRestrictedFieldAssignedToNull("testNullRestrictedStaticFieldCannotBeAssignedNull", "testNullRestrictedStaticFieldCannotBeAssignedNullField");
+			Class<?> c = ValhallaAttributeGenerator.generatePutStaticNullToNullRestrictedField("TestPutStaticNullToNullRestrictedField", "TestPutStaticNullToNullRestrictedFieldField");
 			c.newInstance();
 		} catch(java.lang.ExceptionInInitializerError e) {
 			if (e.getCause() instanceof NullPointerException) {
@@ -129,4 +129,10 @@ static public void testNullRestrictedStaticFieldCannotBeAssignedNull() throws Th
 		}
 		Assert.fail("Test expected a NullPointerException wrapped in ExceptionInInitializerError.");
 	}
+
+	@Test(expectedExceptions = java.lang.NullPointerException.class)
+	static public void testWithFieldStoreNullToNullRestrictedField() throws Throwable {
+		Class<?> c = ValhallaAttributeGenerator.generateWithFieldStoreNullToNullRestrictedField("TestWithFieldStoreNullToNullRestrictedField", "TestWithFieldStoreNullToNullRestrictedFieldField");
+		c.newInstance();
+	}
 }