Interface methods can also call protected methods.

Test: 856-clone
Bug: 343164802
Change-Id: Ic4d93d4a7a6fbfbf854a36d01e28a16c16793307

5 files changed, 41 insertions, 1 deletions

diff --git a/runtime/mirror/class-inl.h b/runtime/mirror/class-inl.h
index 74776c14d4..b2c8e52351 100644
--- a/runtime/mirror/class-inl.h
+++ b/runtime/mirror/class-inl.h
@@ -1169,7 +1169,16 @@ inline bool Class::CanAccessMember(ObjPtr<Class> access_to, uint32_t member_flag
   }
   // Check for protected access from a sub-class, which may or may not be in the same package.
   if (member_flags & kAccProtected) {
-    if (!this->IsInterface() && this->IsSubClass(access_to)) {
+    // This implementation is not compliant. We should actually check whether
+    // the caller is a subclass of the static type of the receiver, instead of the declaring
+    // class of the method we are trying to access.
+    //
+    // For example, a class outside of java.lang should not ne able to access `Object.clone`,
+    // but this implementation allows it.
+    //
+    // To not break existing code, we decided not to fix this and accept the
+    // leniency.
+    if (access_to->IsAssignableFrom(this)) {
       return true;
     }
   }
diff --git a/test/856-clone/expected-stderr.txt b/test/856-clone/expected-stderr.txt
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/test/856-clone/expected-stderr.txt
diff --git a/test/856-clone/expected-stdout.txt b/test/856-clone/expected-stdout.txt
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/test/856-clone/expected-stdout.txt
diff --git a/test/856-clone/info.txt b/test/856-clone/info.txt
new file mode 100644
index 0000000000..c94aab511f
--- /dev/null
+++ b/test/856-clone/info.txt
@@ -0,0 +1,2 @@
+Regression test for calling `Object.clone` from within an default interface
+method.
diff --git a/test/856-clone/src/Main.java b/test/856-clone/src/Main.java
new file mode 100644
index 0000000000..278cfd9542
--- /dev/null
+++ b/test/856-clone/src/Main.java
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2024 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.
+ */
+
+interface I {
+  default String[] myClone(String[] strings) {
+    return strings.clone();
+  }
+}
+
+class A implements I {}
+
+public class Main {
+  public static void main(String[] args) {
+    new A().myClone(args);
+  }
+}