diff --git a/libs/gui/BufferQueueConsumer.cpp b/libs/gui/BufferQueueConsumer.cpp
index ca2a374..73d2042 100644
--- a/libs/gui/BufferQueueConsumer.cpp
+++ b/libs/gui/BufferQueueConsumer.cpp
@@ -715,6 +715,7 @@
 }
 
 sp<NativeHandle> BufferQueueConsumer::getSidebandStream() const {
+    Mutex::Autolock lock(mCore->mMutex);
     return mCore->mSidebandStream;
 }