diff --git a/sys/tools/embed_mfs.sh b/sys/tools/embed_mfs.sh
--- a/sys/tools/embed_mfs.sh
+++ b/sys/tools/embed_mfs.sh
@@ -34,60 +34,60 @@
 #

 if [ $# -ne 2 ]; then
-       echo "usage: $(basename $0) target mfs_image"
+       echo "usage: $(basename "$0") target mfs_image"
        exit 0
 fi
 if [ ! -w "$1" ]; then
-       echo $1 not writable
+       echo "$1" not writable
        exit 1
 fi

-mfs_size=`stat -f '%z' $2 2> /dev/null`
+mfs_size=$(stat -f '%z' "$2" 2> /dev/null)
 # If we can't determine MFS image size - bail.
-if [ -z ${mfs_size} ]; then
+if [ -z "${mfs_size}" ]; then
        echo "Can't determine MFS image size"
        exit 1
 fi

 err_no_mfs="Can't locate mfs section within "

-if file -b $1 | grep -q '^ELF ..-bit .SB executable'; then
+if file -b "$1" | grep -q '^ELF ..-bit .SB executable'; then

-       sec_info=`elfdump -c $1 2> /dev/null | grep -A 5 -E "sh_name: oldmfs$"`
+       sec_info=$(elfdump -c "$1" 2> /dev/null | grep -A 5 -E "sh_name: oldmfs$")
        # If we can't find the mfs section within the given kernel - bail.
        if [ -z "${sec_info}" ]; then
                echo "${err_no_mfs} $1"
                exit 1
        fi

-       sec_size=`echo "${sec_info}" | awk '/sh_size/ {print $2}' 2>/dev/null`
-       sec_start=`echo "${sec_info}" | \
-           awk '/sh_offset/ {print $2}' 2>/dev/null`
+       sec_size=$(echo "${sec_info}" | awk '/sh_size/ {print $2}' 2>/dev/null)
+       sec_start=$(echo "${sec_info}" | \
+           awk '/sh_offset/ {print $2}' 2>/dev/null)

 else

        #try to find start byte of MFS start flag otherwise - bail.
-       sec_start=`strings -at d $1 | grep "MFS Filesystem goes here"` || \
+       sec_start=$(strings -at d "$1" | grep "MFS Filesystem goes here") || \
            { echo "${err_no_mfs} $1"; exit 1; }
-       sec_start=`echo ${sec_start} | awk '{print $1}'`
+       sec_start=$(echo "${sec_start}" | awk '{print $1}')

        #try to find start byte of MFS end flag otherwise - bail.
-       sec_end=`strings -at d $1 | \
-           grep "MFS Filesystem had better STOP here"` || \
+       sec_end=$(strings -at d "$1" | \
+           grep "MFS Filesystem had better STOP here") || \
            { echo "${err_no_mfs} $1"; exit 1; }
-       sec_end=`echo ${sec_end} | awk '{print $1}'`
+       sec_end=$(echo "${sec_end}" | awk '{print $1}')

        #calculate MFS section size
-       sec_size=`expr ${sec_end} - ${sec_start}`
+       sec_size=$(( sec_end - sec_start))

 fi

 # If the mfs section size is smaller than the mfs image - bail.
-if [ ${sec_size} -lt ${mfs_size} ]; then
+if [ "${sec_size}" -lt "${mfs_size}" ]; then
        echo "MFS image too large"
        exit 1
 fi

 # Dump the mfs image into the mfs section
-dd if=$2 ibs=8192 of=$1 obs=${sec_start} oseek=1 conv=notrunc 2> /dev/null && \
+dd if="$2" ibs=8192 of="$1" obs="${sec_start}" oseek=1 conv=notrunc 2> /dev/null && \
     echo "MFS image embedded into $1" && exit 0