diff --git a/install.sh b/install.sh
index c7b1abc..2ce175e 100644
--- a/install.sh
+++ b/install.sh
@@ -72,7 +72,7 @@ rm -rf $MOUNT && mkdir -p $MOUNT
 
 mount -t ext4 -o loop,offset=$OFFSET $SYSTEM $MOUNT 2>/dev/null && PRIVILEGED=true
 
-rm -rf $MOUNT/{,.[!.],..?}*
+rm -rf ${MOUNT:?}/{,.[!.],..?}*
 
 mv -f $HDA.tgz $HDA.txz
 tar xpfJ $HDP.txz --absolute-names -C $MOUNT/