diff --git a/board/stmicroelectronics/common/stm32f4xx/stm32-post-build.sh b/board/stmicroelectronics/common/stm32f4xx/stm32-post-build.sh
index 4fcce61500..2c5b6be098 100755
--- a/board/stmicroelectronics/common/stm32f4xx/stm32-post-build.sh
+++ b/board/stmicroelectronics/common/stm32f4xx/stm32-post-build.sh
@@ -1,4 +1,5 @@
 #!/bin/sh
+set -eu
 
 # Busybox is built without network support
 sed -i '/hostname/d' ${TARGET_DIR}/etc/inittab