diff --git a/functions b/functions
index 20b83b3cd0..ee35723745 100644
--- a/functions
+++ b/functions
@@ -712,7 +712,7 @@ function create_disk {
     # Create a loopback disk and format it to XFS.
     if [[ -e ${disk_image} ]]; then
         if egrep -q ${storage_data_dir} /proc/mounts; then
-            sudo umount ${storage_data_dir}/drives/sdb1
+            sudo umount ${storage_data_dir}
             sudo rm -f ${disk_image}
         fi
     fi