diff --git a/sys/tools/fdt/embed_dtb.sh b/sys/tools/fdt/embed_dtb.sh
--- a/sys/tools/fdt/embed_dtb.sh
+++ b/sys/tools/fdt/embed_dtb.sh
@@ -33,13 +33,13 @@
 # $1: kernel filename
 # $2: device tree blob filename
 
-dtbsize=`ls -l $2 | awk '{print $5}'`
-obs=`strings -at d $1 | grep "Device Tree Blob STARTS here" | awk '{print $1}'`
-eol=`strings -at d $1 | grep "Device Tree Blob STOPS here" | awk '{print $1}'`
+dtbsize=$(stat -f "%z" ${2})
+obs=$(strings -at d "${1}" | awk '/Device Tree Blob STARTS here/ {print $1}')
+eol=$(strings -at d "${1}" | awk '/Device Tree Blob STOPS here/ {print $1}')
 sz=$((eol - obs));
-if [ $sz -lt $dtbsize ]
+if [ ${sz} -lt "${dtbsize}" ]
 then
 	echo "Selected blob is too big to reembed. Please rebuild the kernel."
 	exit
 fi
-dd if=$2 ibs=${dtbsize} of=$1 obs=${obs} oseek=1 conv=notrunc 2> /dev/null
+dd if="${2}" ibs="${dtbsize}" of="${1}" obs="${obs}" oseek=1 conv=notrunc 2> /dev/null
diff --git a/sys/tools/fdt/make_dtbh.sh b/sys/tools/fdt/make_dtbh.sh
--- a/sys/tools/fdt/make_dtbh.sh
+++ b/sys/tools/fdt/make_dtbh.sh
@@ -4,5 +4,5 @@
 
 # Script generates a $2/fdt_static_dtb.h file.
 
-dtb_base_name=`basename $1 .dts`
-echo '#define FDT_DTB_FILE "'${dtb_base_name}.dtb'"' > $2/fdt_static_dtb.h
+dtb_base_name=$(basename "${1}" .dts)
+echo '#define FDT_DTB_FILE "'${dtb_base_name}.dtb'"' > "${2}/fdt_static_dtb.h"