diff --git a/libs/ui/Gralloc1On0Adapter.cpp b/libs/ui/Gralloc1On0Adapter.cpp
index d5b88de..ec7df31 100644
--- a/libs/ui/Gralloc1On0Adapter.cpp
+++ b/libs/ui/Gralloc1On0Adapter.cpp
@@ -288,6 +288,7 @@
 gralloc1_error_t Gralloc1On0Adapter::retain(
         const std::shared_ptr<Buffer>& buffer)
 {
+    std::lock_guard<std::mutex> lock(mBufferMutex);
     buffer->retain();
     return GRALLOC1_ERROR_NONE;
 }
@@ -295,6 +296,7 @@
 gralloc1_error_t Gralloc1On0Adapter::release(
         const std::shared_ptr<Buffer>& buffer)
 {
+    std::lock_guard<std::mutex> lock(mBufferMutex);
     if (!buffer->release()) {
         return GRALLOC1_ERROR_NONE;
     }
@@ -314,7 +316,6 @@
         }
     }
 
-    std::lock_guard<std::mutex> lock(mBufferMutex);
     mBuffers.erase(handle);
     return GRALLOC1_ERROR_NONE;
 }