diff --git a/package/base-files/files/lib/functions.sh b/package/base-files/files/lib/functions.sh
index 2ed353b2a5..b3a3885f2d 100755
--- a/package/base-files/files/lib/functions.sh
+++ b/package/base-files/files/lib/functions.sh
@@ -220,6 +220,15 @@ include() {
 	done
 }
 
+find_mtd_part() {
+	local PART="$(grep "\"$1\"" /proc/mtd | awk -F: '{print $1}')"
+	local PREFIX=/dev/mtdblock
+
+	PART="${PART##mtd}"
+	[ -d /dev/mtdblock ] && PREFIX=/dev/mtdblock/
+	echo "${PART:+$PREFIX$PART}"
+}
+
 strtok() { # <string> { <variable> [<separator>] ... }
 	local tmp
 	local val="$1"