BTRFS and Qubes OS

[rustybird]

@alimirjamali

converting (from ext4 to btrfs) and resizing the private.img files directly in dom0

That’s insecure (unless the ‘private’ volume hasn’t been initialized yet after creating the qube, or the volume has been cleared):

@rustybird

Never run filesystem utilities on (or worse: mount) VM filesystems in dom0. The filesystem on-disk format itself, and not just the files stored in it, is a complex data structure that’s fully controlled by the VM, so it’s best treated as potentially malicious. Filesystem utilities (or kernel filesystem code) can’t be assumed to be robust against this.