diff --git a/VolumeBase.cpp b/VolumeBase.cpp
index ea4d372..627feba 100644
--- a/VolumeBase.cpp
+++ b/VolumeBase.cpp
@@ -219,7 +219,7 @@
     }
 
     setState(State::kEjecting);
-    for (auto vol : mVolumes) {
+    for (const auto& vol : mVolumes) {
         if (vol->destroy()) {
             LOG(WARNING) << getId() << " failed to destroy " << vol->getId()
                     << " stacked above";