diff --git a/tools/r1_patcher/r1_patcher.sh b/tools/r1_patcher/r1_patcher.sh
index e0f3e68ab5..43a87c3d58 100755
--- a/tools/r1_patcher/r1_patcher.sh
+++ b/tools/r1_patcher/r1_patcher.sh
@@ -12,39 +12,39 @@ fi
 ### init
 ################################################################################
 
-currentdir=$(pwd)
-updatefile="$(basename $1)"
+currentdir="$(pwd)"
+updatefile="$(basename "$1")"
 updatefile_rb="${updatefile%.*}_rb.upt"
 
-workingdir=$(realpath ./working_dir)
-workingdir_in=$workingdir"/in"
-workingdir_out=$workingdir"/out"
+workingdir="$(realpath ./working_dir)"
+workingdir_in="$workingdir/in"
+workingdir_out="$workingdir/out"
 
-rm -rf $workingdir
+rm -rf "$workingdir"
 
-mkdir $workingdir
-mkdir $workingdir_in
-mkdir $workingdir_out
+mkdir "$workingdir"
+mkdir "$workingdir_in"
+mkdir "$workingdir_out"
 
 ################################################################################
 ### extract
 ################################################################################
 
 # extract iso
-mkdir -p $workingdir_in/image_contents
-7z -o$workingdir_in/image_contents x $updatefile
+mkdir -p "$workingdir_in/image_contents"
+7z -o"$workingdir_in/image_contents" x "$updatefile"
 
 # create xImage (unchanged)
-mkdir -p $workingdir_out/xImage
-cat $workingdir_in/image_contents/ota_v0/xImage.* > $workingdir_out/xImage/xImage
+mkdir -p "$workingdir_out/xImage"
+cat "$workingdir_in/image_contents/ota_v0"/xImage.* > "$workingdir_out/xImage/xImage"
 
 # create rootfs
-mkdir -p $workingdir_in/rootfs
-mkdir -p $workingdir_in/rootfs/extracted
-cat $workingdir_in/image_contents/ota_v0/rootfs.squashfs.* > $workingdir_in/rootfs/rootfs.squashfs
+mkdir -p "$workingdir_in/rootfs"
+mkdir -p "$workingdir_in/rootfs/extracted"
+cat "$workingdir_in/image_contents/ota_v0"/rootfs.squashfs.* > "$workingdir_in/rootfs/rootfs.squashfs"
 
 # extract rootfs
-unsquashfs -f -d $workingdir_in/rootfs/extracted $workingdir_in/rootfs/rootfs.squashfs
+unsquashfs -f -d "$workingdir_in/rootfs/extracted" "$workingdir_in/rootfs/rootfs.squashfs"
 
 ################################################################################
 ### update
@@ -55,15 +55,15 @@ cp "$2" "$workingdir_in/rootfs/extracted/usr/bin/bootloader.rb"
 chmod 0755 "$workingdir_in/rootfs/extracted/usr/bin/bootloader.rb"
 
 # copy modified 'hibyplayer.sh' script
-cp hiby_player.sh $workingdir_in/rootfs/extracted/usr/bin/
-chmod 0755 $workingdir_in/rootfs/extracted/usr/bin/hiby_player.sh
+cp hiby_player.sh "$workingdir_in/rootfs/extracted/usr/bin/"
+chmod 0755 "$workingdir_in/rootfs/extracted/usr/bin/hiby_player.sh"
 
 ################################################################################
 ### Rockbox Hotplug Logic
 ################################################################################
 
 # 1. Create hotplug helper script
-cat << 'EOF' > $workingdir_in/rootfs/extracted/usr/bin/rb_hotplug.sh
+cat << 'EOF' > "$workingdir_in/rootfs/extracted/usr/bin/rb_hotplug.sh"
 #!/bin/sh
 MNT_SD="/data/mnt/sd_0"
 MNT_USB="/data/mnt/usb"
@@ -84,7 +84,7 @@ case "$ACTION" in
         ;;
 esac
 EOF
-chmod 0755 $workingdir_in/rootfs/extracted/usr/bin/rb_hotplug.sh
+chmod 0755 "$workingdir_in/rootfs/extracted/usr/bin/rb_hotplug.sh"
 
 # 2. Check mdev.conf and append rules only if missing
 MDEV_CONF="$workingdir_in/rootfs/extracted/etc/mdev.conf"
@@ -103,39 +103,39 @@ fi
 
 mkdir -p "$workingdir_out/image_contents/ota_v0"
 
-mksquashfs $workingdir_in/rootfs/extracted $workingdir_out/rootfs.squashfs -comp lzo -all-root
+mksquashfs "$workingdir_in/rootfs/extracted" "$workingdir_out/rootfs.squashfs" -comp lzo -all-root
 
 cd "$workingdir_out/image_contents/ota_v0"
 
 # rootfs.squashfs
-split -b 512k $workingdir_out/rootfs.squashfs --numeric-suffixes=0 -a 4 rootfs.squashfs.
+split -b 512k "$workingdir_out/rootfs.squashfs" --numeric-suffixes=0 -a 4 rootfs.squashfs.
 
-rootfs_md5=($(md5sum $workingdir_out/rootfs.squashfs))
+rootfs_md5=($(md5sum "$workingdir_out/rootfs.squashfs"))
 rootfs_size=$(stat -c%s "$workingdir_out/rootfs.squashfs")
 md5=$rootfs_md5
 
 ota_md5_rootfs="ota_md5_rootfs.squashfs.$md5"
 
 for part in $(ls rootfs.squashfs.[0-9]* | sort); do
-    md5next=($(md5sum $part))
+    md5next=($(md5sum "$part"))
     echo $md5next >> $ota_md5_rootfs
-    mv $part "$part.$md5"
+    mv "$part" "$part.$md5"
     md5=$md5next
 done
 
 # xImage
-split -b 512k $workingdir_out/xImage/xImage --numeric-suffixes=0 -a 4 xImage.
+split -b 512k "$workingdir_out/xImage/xImage" --numeric-suffixes=0 -a 4 xImage.
 
-ximage_md5=($(md5sum $workingdir_out/xImage/xImage))
+ximage_md5=($(md5sum "$workingdir_out/xImage/xImage"))
 ximage_size=$(stat -c%s "$workingdir_out/xImage/xImage")
 md5=$ximage_md5
 
 ota_md5_xImage="ota_md5_xImage.$md5"
 
 for part in $(ls xImage.[0-9]* | sort); do
-    md5next=($(md5sum $part))
+    md5next=($(md5sum "$part"))
     echo $md5next >> $ota_md5_xImage
-    mv $part "$part.$md5"
+    mv "$part" "$part.$md5"
     md5=$md5next
 done
 
@@ -162,12 +162,12 @@ cd "$workingdir_out/image_contents"
 echo "current_version=0" > ota_config.in
 
 # iso
-genisoimage -f -U -J -joliet-long -r -allow-lowercase -allow-multidot -o $currentdir/$updatefile_rb $workingdir_out/image_contents/
+genisoimage -f -U -J -joliet-long -r -allow-lowercase -allow-multidot -o "$currentdir/$updatefile_rb" "$workingdir_out/image_contents/"
 
 ################################################################################
 ### cleanup
 ################################################################################
 
-rm -rf $workingdir
+rm -rf "$workingdir"
 
 exit 0