Forbid root login with password

Makefile

@@ -16,7 +16,7 @@ root_overlay: root_overlay/root/key
 
 root_overlay/root/.ssh/authorized_keys: ~/.ssh/id_rsa.pub
 	mkdir -p `dirname $@`
-	cp ^< $@
+	cp $< $@
 
 buildroot/.config: config
 	ln -sf ../config $@

config

@@ -1,6 +1,6 @@
 #
 # Automatically generated file; DO NOT EDIT.
-# Buildroot 2021.02-rc2-dirty Configuration
+# Buildroot 2021.02-rc2 Configuration
 #
 BR2_HAVE_DOT_CONFIG=y
 BR2_EXTERNAL_DOOR_PI_PATH="/home/apo/Projects/Hackerspace/DoorPi/br_external"
@@ -445,9 +445,9 @@ BR2_ROOTFS_SKELETON_DEFAULT=y
 # BR2_ROOTFS_SKELETON_CUSTOM is not set
 BR2_TARGET_GENERIC_HOSTNAME="OrangePi_Zero"
 BR2_TARGET_GENERIC_ISSUE="Welcome to Buildroot for the Orange Pi Zero"
-BR2_TARGET_GENERIC_PASSWD_SHA256=y
-# BR2_TARGET_GENERIC_PASSWD_SHA512 is not set
-BR2_TARGET_GENERIC_PASSWD_METHOD="sha-256"
+# BR2_TARGET_GENERIC_PASSWD_SHA256 is not set
+BR2_TARGET_GENERIC_PASSWD_SHA512=y
+BR2_TARGET_GENERIC_PASSWD_METHOD="sha-512"
 BR2_INIT_BUSYBOX=y
 # BR2_INIT_SYSV is not set
 # BR2_INIT_OPENRC is not set
@@ -463,8 +463,7 @@ BR2_ROOTFS_DEVICE_CREATION_DYNAMIC_EUDEV=y
 BR2_ROOTFS_DEVICE_TABLE="system/device_table.txt"
 # BR2_ROOTFS_DEVICE_TABLE_SUPPORTS_EXTENDED_ATTRIBUTES is not set
 # BR2_ROOTFS_MERGED_USR is not set
-BR2_TARGET_ENABLE_ROOT_LOGIN=y
-BR2_TARGET_GENERIC_ROOT_PASSWD="hello"
+# BR2_TARGET_ENABLE_ROOT_LOGIN is not set
 BR2_SYSTEM_BIN_SH_BUSYBOX=y
 # BR2_SYSTEM_BIN_SH_BASH is not set
 # BR2_SYSTEM_BIN_SH_DASH is not set