Bug with makefile that can erase host MBR

Makefile

@@ -328,7 +328,7 @@ dddnokvm: all installonimage
 ## HD IMAGE RELATED ---------------------------------------------------------- #
 
 installonimage: $(installdisk) $(MBRDIR)/grub.cfg
-	@echo ${CL2}[$@] ${NC}Installing MBR on image...${CL3}
+	@echo ${CL2}[$@] ${NC}Installing boot configuration on image...${CL3}
 	@$(BUILDDIR)/install-os-k.sh $(installdisk) $(MBRDIR)/grub.cfg $(BINDIR)/kaleid
 	@echo ${CL2}[$@] ${CL}Success.${CL3}
 

build/create_disk.sh

@@ -76,7 +76,7 @@ fi
 
 if [ -z $lpblock ];
 then
-	echo No loop device partition to target. Fatal error !
+	Impossible to find an available loop device. Fatal error !
 	return 13
 fi
 

build/install-os-k.sh

@@ -30,33 +30,27 @@ NC='\033[1;37m'
 
 set -e #exit if error
 
-## Mount
-echo ${CL2}[install-os-k.sh]${NC} Mount image... 		\(losetup\)${CL3}
-lpblock=$(sudo losetup -f)
-sudo losetup $lpblock $1 -o 1048576
+echo ${CL2}[install-os-k.sh]${NC} Mount image... 		\(udisksctl\)${CL3}
+udisksctl loop-setup --offset 1048576 --no-user-interaction --file $1
+lpblock=$(/sbin/losetup -j $1 | cut -d ':' -f 1)
 
-if [ -z $lpblock ];
-then
-	echo No loop device partition to target. Fatal error !
-	return 13
-fi
-
-sudo udisksctl mount -b $lpblock --no-user-interaction
-
-## Sync
 echo ${CL2}[install-os-k.sh]${NC} Sync image... 		\(sync\)${CL3}
 sync
 
-# Get the mountpoint
+if [ -z $lpblock ];
+then
+	echo Impossible to find an available loop device. Fatal error !
+	return 13
+fi
+
 mountpoint=$(udisksctl info -b $lpblock | grep MountPoint | cut -d ':' -f 2 | sed 's/ //g')
 
 if [ -z $mountpoint ];
 then
-	echo Impossible to mount the image $mountpoint. Fatal error !
+	echo Impossible to mount the image at $lpblock. Fatal error !
 	return 13
 fi
 
-
 echo ${CL2}[install-os-k.sh]${NC} Copying grub.cfg
 cp $2 $mountpoint/boot/grub/grub.cfg
 echo ${CL2}[install-os-k.sh]${NC} Copying kernel