SteamOS Recovery Repack Tools

These tools allow you to extract and repack SteamOS Recovery superimages that contain multiple nested filesystem partitions (rootfs, var, home, EFI/ESP).

• img2dsk — Extract the Linux filesystem tree (rootfs, /var, /home) from a superimage into a normal directory so you can edit it.
• repack_superimage — Repack a new superimage by replacing rootfs, /var, and /home from an edited tree.

Both tools support:

• Debian/Ubuntu
• Fedora/RHEL/CentOS
• Arch Linux
• GUI mode (Tkinter) and CLI mode

The only issue is that in future recovery images valve may change the partition layout. If they do, the scripts will need to be updated.

Works in WSL

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📦 Dependencies

Debian / Ubuntu

sudo apt update
sudo apt install -y util-linux rsync e2fsprogs file squashfs-tools python3-tk

Fedora / RHEL / CentOS Stream

sudo dnf install -y util-linux rsync e2fsprogs file squashfs-tools python3-tkinter

Arch Linux

sudo pacman -S --needed util-linux rsync e2fsprogs file squashfs-tools tk

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🔎 Extracting a Superimage (img2dsk)

img2dsk mounts the partitions of a superimage, detects nested images (rootfs-A.img, var-A.img, home.img, squashfs, etc.), and copies them out into a normal directory tree.
This allows you to chroot, edit configs, rebuild packages, etc.

CLI Usage

# Extract full rootfs + var + home
sudo ./img2dsk.py steamdeck.img /mnt/steamOS

• Rootfs is extracted into /mnt/steamOS/
• /var into /mnt/steamOS/var/
• /home into /mnt/steamOS/home/

GUI Usage

sudo ./img2dsk_arch.py --gui      # Arch version
sudo ./img2dsk_fedora.py --gui    # Fedora/RHEL version
sudo ./img2dsk.py --gui           # Generic version (if provided)

In the GUI, just select:

1. The .img superimage
2. The output directory
3. Click Extract

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🔄 Repacking a Superimage (repack_superimage)

repack_superimage takes an old superimage and an edited filesystem tree (from img2dsk), and creates a new .img.
It preserves GPT and EFI/ESP partitions, while replacing rootfs, /var, and /home.

CLI Usage

# Repack with rootfs, var, and home
sudo ./repack_superimage.py --old steamdeck.img --root /mnt/steamOS --out new_steamdeck.img

# Skip /var
sudo ./repack_superimage.py --old steamdeck.img --root /mnt/steamOS --out new.img --no-var

# Skip /home
sudo ./repack_superimage.py --old steamdeck.img --root /mnt/steamOS --out new.img --no-home

GUI Usage

sudo ./repack_superimage.py --gui

In the GUI, select:

1. Old/original superimage (steamdeck.img)
2. Edited root directory (where img2dsk extracted)
3. Output .img path
4. Choose whether to include /var and /home
5. Click Repack

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⚠️ Notes & Caveats

• Both tools must be run as root (sudo) to attach loop devices and mount partitions.
• ESP/EFI partitions are preserved as-is (bootloaders not rebuilt).
• Repack script tries to auto-detect squashfs vs ext4 rootfs and rebuild accordingly.
• On Fedora/RHEL with SELinux, after booting from the repacked image, run: sudo restorecon -R / to fix SELinux file contexts.
• If your edited filesystem tree is larger than the existing partition space, the repack will fail with a "not enough space" warning.
  In that case, you must resize partitions or reduce contents.

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🗂 File Overview

• img2dsk.py
  Simple cross-distro extractor (CLI only).
• img2dsk_arch.py / img2dsk_fedora.py
  Extraction with CLI + GUI for Arch and Fedora/RHEL.
• repack_superimage.py
  Repacking tool (CLI + GUI) for all supported distros.

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Example Workflow

1. Extract sudo ./img2dsk.py steamdeck.img /mnt/steamOS

2. Edit sudo arch-chroot /mnt/steamOS # make changes: install packages, edit configs, etc. exit

3. Repack sudo ./repack_superimage.py --old steamdeck.img --root /mnt/steamOS --out steamdeck_custom.img

4. Write to USB / SD card sudo dd if=steamdeck_custom.img of=/dev/sdX bs=4M status=progress