diff --git a/debian/changelog b/debian/changelog
index d2fef2df..6b95a0ce 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,7 @@
-livecd-rootfs (2.457ubuntu1) UNRELEASED; urgency=medium
+livecd-rootfs (2.458) artful; urgency=medium
 
   * Add GENERATE_ROOTFS_ONLY to support generating a single rootfs.
+  * Add a test for SUBPROJECT when PROJECT comes to ubuntu-server.
 
  -- Gary Wang <gary.wang@canonical.com>  Mon, 18 Sep 2017 09:51:04 +0800
 
diff --git a/live-build/auto/build b/live-build/auto/build
index 156f7789..35de4f81 100755
--- a/live-build/auto/build
+++ b/live-build/auto/build
@@ -235,7 +235,7 @@ EOF
 	fi
 ) 2>&1 | tee binary.log
 
-if [ ! -z "${GENERATE_ROOTFS_ONLY:-}" ] && [ "${GENERATE_ROOTFS_ONLY}" != "false" ]; then
+if [ ! -z "${GENERATE_ROOTFS_ONLY:-}" ] && [ "${GENERATE_ROOTFS_ONLY}" = 1 ]; then
 	exit 0
 fi
 
diff --git a/live-build/auto/config b/live-build/auto/config
index 3f504463..f8515239 100755
--- a/live-build/auto/config
+++ b/live-build/auto/config
@@ -757,7 +757,7 @@ EOF
 		;;
 esac
 
-if [ $PROJECT = ubuntu-server ] && [ $SUBPROJECT != live ]; then
+if [ $PROJECT = ubuntu-server ] && [ ! -z "${SUBPROJECT:-}" ] && [ $SUBPROJECT != live ]; then
 	cat > config/hooks/100-remove-fstab.chroot <<EOF
 #! /bin/sh
 rm -f /etc/fstab