--- a/gfx/layers/ipc/SharedBufferManagerParent.cpp
+++ b/gfx/layers/ipc/SharedBufferManagerParent.cpp
@@ -359,17 +359,21 @@ SharedBufferManagerParent::GetGraphicBuf
     return nullptr;
   }
 }
 
 android::sp<android::GraphicBuffer>
 SharedBufferManagerParent::GetGraphicBuffer(GrallocBufferRef aRef)
 {
   MonitorAutoLock lock(*sManagerMonitor.get());
-  return GetInstance(aRef.mOwner)->GetGraphicBuffer(aRef.mKey);
+  SharedBufferManagerParent* parent = GetInstance(aRef.mOwner);
+  if (!parent) {
+    return nullptr;
+  }
+  return parent->GetGraphicBuffer(aRef.mKey);
 }
 #endif
 
 IToplevelProtocol*
 SharedBufferManagerParent::CloneToplevel(const InfallibleTArray<ProtocolFdMapping>& aFds,
                                  base::ProcessHandle aPeerProcess,
                                  mozilla::ipc::ProtocolCloneContext* aCtx)
 {

--- a/gfx/layers/opengl/GrallocTextureHost.cpp
+++ b/gfx/layers/opengl/GrallocTextureHost.cpp
@@ -226,16 +226,19 @@ GrallocTextureHostOGL::GetRenderState()
   }
 
   return LayerRenderState();
 }
 
 TemporaryRef<gfx::DataSourceSurface>
 GrallocTextureHostOGL::GetAsSurface() {
   android::GraphicBuffer* graphicBuffer = GetGraphicBufferFromDesc(mGrallocHandle).get();
+  if (!graphicBuffer) {
+    return nullptr;
+  }
   uint8_t* grallocData;
   graphicBuffer->lock(GRALLOC_USAGE_SW_READ_OFTEN, reinterpret_cast<void**>(&grallocData));
   RefPtr<gfx::DataSourceSurface> grallocTempSurf =
     gfx::Factory::CreateWrappingDataSourceSurface(grallocData,
                                                   graphicBuffer->getStride() * android::bytesPerPixel(graphicBuffer->getPixelFormat()),
                                                   GetSize(), GetFormat());
   RefPtr<gfx::DataSourceSurface> surf = CreateDataSourceSurfaceByCloning(grallocTempSurf);