Port "Avoid method overriding if its super method is inaccessible" to art.

This is an art equivalent of https://android-review.googlesource.com/#/c/32480/3.

Change-Id: Ifc2cd21e7e92f596bced3eabae4d16f16f4095ef

7 files changed, 71 insertions, 31 deletions

diff --git a/src/class_linker.cc b/src/class_linker.cc
index 990fb62..2b20aff 100644
--- a/src/class_linker.cc
+++ b/src/class_linker.cc
@@ -2850,7 +2850,8 @@ bool ClassLinker::LinkVirtualMethods(SirtRef<Class>& klass) {
       for (; j < actual_count; ++j) {
         Method* super_method = vtable->Get(j);
         super_mh.ChangeMethod(super_method);
-        if (local_mh.HasSameNameAndSignature(&super_mh)) {
+        if (local_mh.HasSameNameAndSignature(&super_mh) &&
+            klass->CanAccessMember(super_method->GetDeclaringClass(), super_method->GetAccessFlags())) {
           // Verify
           if (super_method->IsFinal()) {
             MethodHelper mh(local_method);
diff --git a/src/native/java_lang_Class.cc b/src/native/java_lang_Class.cc
index ecab777..bc1d0de 100644
--- a/src/native/java_lang_Class.cc
+++ b/src/native/java_lang_Class.cc
@@ -354,35 +354,6 @@ static jboolean Class_isAssignableFrom(JNIEnv* env, jobject javaLhs, jclass java
   return lhs->IsAssignableFrom(rhs) ? JNI_TRUE : JNI_FALSE;
 }
 
-// Validate method/field access.
-static bool CheckMemberAccess(const Class* access_from, Class* access_to, uint32_t member_flags) {
-  // quick accept for public access */
-  if (member_flags & kAccPublic) {
-    return true;
-  }
-
-  // quick accept for access from same class
-  if (access_from == access_to) {
-    return true;
-  }
-
-  // quick reject for private access from another class
-  if (member_flags & kAccPrivate) {
-    return false;
-  }
-
-  // Semi-quick test for protected access from a sub-class, which may or
-  // may not be in the same package.
-  if (member_flags & kAccProtected) {
-    if (access_from->IsSubClass(access_to)) {
-        return true;
-    }
-  }
-
-  // Allow protected and private access from other classes in the same
-  return access_from->IsInSamePackage(access_to);
-}
-
 static jobject Class_newInstanceImpl(JNIEnv* env, jobject javaThis) {
   ScopedJniThreadState ts(env);
   Class* c = DecodeClass(ts, javaThis);
@@ -424,7 +395,7 @@ static jobject Class_newInstanceImpl(JNIEnv* env, jobject javaThis) {
         PrettyDescriptor(caller_ch.GetDescriptor()).c_str());
     return NULL;
   }
-  if (!CheckMemberAccess(caller_class, init->GetDeclaringClass(), init->GetAccessFlags())) {
+  if (!caller_class->CanAccessMember(init->GetDeclaringClass(), init->GetAccessFlags())) {
     ts.Self()->ThrowNewExceptionF("Ljava/lang/IllegalAccessException;",
         "%s is not accessible from class %s",
         PrettyMethod(init).c_str(),
diff --git a/test/300-package-override/expected.txt b/test/300-package-override/expected.txt
new file mode 100644
index 0000000..b0aad4d
--- /dev/null
+++ b/test/300-package-override/expected.txt
@@ -0,0 +1 @@
+passed
diff --git a/test/300-package-override/info.txt b/test/300-package-override/info.txt
new file mode 100644
index 0000000..0ed59eb
--- /dev/null
+++ b/test/300-package-override/info.txt
@@ -0,0 +1,2 @@
+Tests a dalvik bug where we'd allow subclasses to override package-protected
+methods.
\ No newline at end of file
diff --git a/test/300-package-override/src/Main.java b/test/300-package-override/src/Main.java
new file mode 100644
index 0000000..ad7eaaf
--- /dev/null
+++ b/test/300-package-override/src/Main.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed 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
+ *
+ *      http://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.
+ */
+
+public class Main {
+  public static void main(String args[]) throws Exception {
+    p1.BaseClass c = new p2.DerivedClass();
+    c.run();
+  }
+}
diff --git a/test/300-package-override/src/p1/BaseClass.java b/test/300-package-override/src/p1/BaseClass.java
new file mode 100644
index 0000000..1c048ac
--- /dev/null
+++ b/test/300-package-override/src/p1/BaseClass.java
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed 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
+ *
+ *      http://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 p1;
+
+public class BaseClass {
+  public void run() { foo(); }
+  void foo() { System.out.println("passed"); } // It should not be possible to override this.
+}
diff --git a/test/300-package-override/src/p2/DerivedClass.java b/test/300-package-override/src/p2/DerivedClass.java
new file mode 100644
index 0000000..860f50c
--- /dev/null
+++ b/test/300-package-override/src/p2/DerivedClass.java
@@ -0,0 +1,21 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed 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
+ *
+ *      http://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 p2;
+
+public class DerivedClass extends p1.BaseClass {
+  void foo() { System.out.println("DerivedClass overrode package-private method!"); } // This should not override BaseClass.foo.
+}