So run it on a VM/throwaway machine. Once you achieve that level of paranoia it's really turtles all the way down. Next we'll be trying to get rid of e2tools.

So run it on a VM/throwaway machine. Once you achieve that level of paranoia it's really turtles all the way down. Next we'll be trying to get rid of e2tools... A properly malicious filesystem will get you a compromised userspace program... big whoop, there are far far far more likely vectors for that, at least manipulating a strange and untrusted filesystem with gparted is something you have to try to do. The danger libguestfs is attempting to avoid does not apply here meaningfully.