diff --git a/firstboot/first-boot-set-mac.sh b/firstboot/first-boot-set-mac.sh
index 1a1ae22..66e41b2 100644
--- a/firstboot/first-boot-set-mac.sh
+++ b/firstboot/first-boot-set-mac.sh
@@ -1,6 +1,6 @@
 #!/bin/bash -eu
 
-show_error() {
+function show_error() {
     if [ -n "${JOURNAL_STREAM-}" ]; then
         echo "$@" | systemd-cat -t first-boot-set-mac -p emerg
     else
@@ -8,7 +8,7 @@
     fi
 }
 
-sync_mac() {
+function sync_mac() {
 
     MAPPER_IFACE='xyz.openbmc_project.ObjectMapper'
     MAPPER_PATH='/xyz/openbmc_project/object_mapper'