diff --git a/buildroot-external/kernel.config b/buildroot-external/kernel.config
index a4c540cb4..e6cd8d557 100644
--- a/buildroot-external/kernel.config
+++ b/buildroot-external/kernel.config
@@ -67,7 +67,7 @@ CONFIG_BRIDGE_NETFILTER=y
 CONFIG_XFRM=y
 CONFIG_XFRM_USER=y
 CONFIG_XFRM_ALGO=y
-CONFIG_NET_L3_MASTER_DEV=Y
+CONFIG_NET_L3_MASTER_DEV=y
 
 CONFIG_EXT4_FS=y
 CONFIG_EXT4_FS_POSIX_ACL=y