Re: [9front] [PATCH] Unmount to remove sharp devices.

[Jacob Moody <moody@mail.posixcafe.org>]

On 5/4/22 11:41, Lyndon Nerenberg (VE7TFX/VE6BBM) wrote:
>> git/serve? rc-httpd? maybe some other daemons
>> could use some sandboxing.
> 
> The FTP and TFTP servers are obvious targets. But what would be
> really cool is if this could be integrated into the namespace
> files. That way you could set up the namespace for something like
> FTP, and then remove the ability to mount #foo without having to
> touch the FTP code itself. I could see myself using this all over
> the place.
> 
> --lyndon

This is already true to some extent as is with this patch.
Adding an 'unmount #e' to your namespace file will remove
access to #e as is. However I want to look a bit more
at doing the inverse operation, so you could say something like
"permit #e #| #p" and have it block all non listed
devices in the namespace file. I think that is more useful
to think about and avoids 10 lines of manually selecting drivers
to shoot.

Perhaps a new /lib/namespace.service could become the default
for networked services. Either way, with the kernel
modifications passing the sniff test, I will spend some
time seeing how to integrate this change in to existing daemons.

Thanks,
moody