diff --git a/package/base-files/files/lib/functions/system.sh b/package/base-files/files/lib/functions/system.sh
index 107e67835a2..23484c8ad91 100644
--- a/package/base-files/files/lib/functions/system.sh
+++ b/package/base-files/files/lib/functions/system.sh
@@ -205,6 +205,7 @@ mmc_get_mac_ascii() {
 	part=$(find_mmc_part "$part_name")
 	if [ -z "$part" ]; then
 		echo "mmc_get_mac_ascii: partition $part_name not found!" >&2
+		return
 	fi
 
 	get_mac_ascii "$part" "$key"