From a8888c1b6513a6f5335e72073efc301c86467e92 Mon Sep 17 00:00:00 2001
From: Hiroshi Yamauchi <yamauchi@google.com>
Date: Fri, 2 Dec 2016 13:58:58 -0800
Subject: [PATCH] Use getReferent() in enqueueSentinelReference to avoid race
 with GC.

This is the art part.

Fix a check failure due to the direct referent access that races with
the GC reference processing for CC.

Bug: 33207594
Bug: 12687968
Test: test-art-host with and without CC.
Change-Id: I3c98066d09dd98d8fddc59b6784c75843b45338b
---
 runtime/native/java_lang_ref_FinalizerReference.cc | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/runtime/native/java_lang_ref_FinalizerReference.cc b/runtime/native/java_lang_ref_FinalizerReference.cc
index c7d06f466..ecafd0e24 100644
--- a/runtime/native/java_lang_ref_FinalizerReference.cc
+++ b/runtime/native/java_lang_ref_FinalizerReference.cc
@@ -31,8 +31,17 @@ static jboolean FinalizerReference_makeCircularListIfUnenqueued(JNIEnv* env, job
   return Runtime::Current()->GetHeap()->GetReferenceProcessor()->MakeCircularListIfUnenqueued(ref);
 }
 
+static jobject FinalizerReference_getReferent(JNIEnv* env, jobject javaThis) {
+  ScopedFastNativeObjectAccess soa(env);
+  ObjPtr<mirror::Reference> ref = soa.Decode<mirror::Reference>(javaThis);
+  ObjPtr<mirror::Object> const referent =
+      Runtime::Current()->GetHeap()->GetReferenceProcessor()->GetReferent(soa.Self(), ref);
+  return soa.AddLocalReference<jobject>(referent);
+}
+
 static JNINativeMethod gMethods[] = {
   NATIVE_METHOD(FinalizerReference, makeCircularListIfUnenqueued, "!()Z"),
+  NATIVE_METHOD(FinalizerReference, getReferent, "!()Ljava/lang/Object;"),
 };
 
 void register_java_lang_ref_FinalizerReference(JNIEnv* env) {
-- 
2.11.0