diff --git a/common/mk-misc.sh b/common/mk-misc.sh
new file mode 100755
index 0000000..26ddccf
--- /dev/null
+++ b/common/mk-misc.sh
@@ -0,0 +1,34 @@
+#!/bin/bash
+
+set -ex
+
+INPUT=$1
+OUTPUT=$2
+SIZE=$3
+BUF=$4
+
+COMMON_DIR=$(dirname $(readlink -f $0))
+ROCKIMG_DIR=${COMMON_DIR}/../rockimg
+
+if [ ! -e ${INPUT} ]; then
+	echo "ERROR: No input file \"${INPUT}\""
+	exit -1
+fi
+
+rm ${ROCKIMG_DIR}/${OUTPUT} || true
+
+if [ ${SIZE} -gt 1024 ]; then
+	echo "ERROR: SIZE bigger than 1K"
+	exit -1
+fi
+
+BIG_END=$[SIZE / 256]
+LIT_END=$[SIZE - (BIG_END * 256)]
+BIG_END=$(echo "ibase=10;obase=16;${BIG_END}" | bc)
+LIT_END=$(echo "ibase=10;obase=16;${LIT_END}" | bc)
+
+dd if=${INPUT} of=${OUTPUT} bs=1k count=10
+echo -en "\x${LIT_END}\x${BIG_END}" >> ${OUTPUT}
+echo -n "$BUF" >> ${OUTPUT}
+SKIP=$[10 * 1024 + SIZE + 2]
+dd if=${INPUT} of=${OUTPUT} seek=${SKIP} skip=${SKIP} bs=1