diff --git a/nix/pkgs/openwrt/uci-config.nix b/nix/pkgs/openwrt/uci-config.nix
index 5098be6..5c3735a 100644
--- a/nix/pkgs/openwrt/uci-config.nix
+++ b/nix/pkgs/openwrt/uci-config.nix
@@ -302,7 +302,7 @@ in
     optionalString (config.site.net ? ${net} &&
                     config.site.net.${net}.mtu != null) ''
       if [ "\\\$ACTION" = ifup -a "\\\$INTERFACE" = ${net} ]; then
-        ip link set ${net} mtu ${toString config.site.net.${net}.mtu}
+        ip link set \\\$DEVICE mtu ${toString config.site.net.${net}.mtu}
       fi
     '') (builtins.attrNames hostConfig.interfaces)
    }