[Feature Request] Use landlock for sandboxing VM process

[arch-hash]

Feature Request

Jailer could use Landlock to confine guest VM's processes further, restricting fine-grained file system access than what current chroot can provide. This would be a defense in depth mechanism if the VM escape or host compromise is attempted.

Describe the desired solution

Landlock would allows apps inside guest VM to have nested sandboxing for file paths.

Describe possible alternatives

Keep using existing chroot trick. But that's not ideal.

Additional context

I'm working on an OS similar to QubesOS where every app is a microVM.

Checks

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[xmarcalx]

Hi @arch-hash ,

Thank you very much for your interesting proposal.

We do not have currently an usecase for having more fine grained file system access, however this is an interesting concept.
Would you be willing to do a mini prototype with our jailer using Landlock and showcase the benefits which we may have in converting our current solution into Landlock (for example, are performance going to be better?)?