diff --git a/scripts/upgrade b/scripts/upgrade
index 0a91891..013cc82 100644
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -394,8 +394,8 @@ fi
 
 # Set files ownership to Etherpad
 chmod 750 "$final_path"
-chmod o-rwx $final_path
-chown -R $app: $final_path
+chmod o-rwx "$final_path"
+chown -R $app: "$final_path"
 # Restrict access to credentials.json
 chmod 600 "$final_path/credentials.json"
 chown $app -R /var/log/$app/etherpad.log