Re: [kernel-hardening] /proc/PID directory hiding (was: [owl-dev] segoon's status report - #1 of 15)

Solar Designer
2011-06-04T21:03:15Z

On Sun, Jun 05, 2011 at 12:20:47AM +0400, Vasiliy Kulikov wrote:
> On Sat, Jun 04, 2011 at 22:19 +0400, Solar Designer wrote:
> > As to probing for PIDs with syscalls such as kill(2), we may deal with
> > that as well
>
> I'd not do this. There are too many paths using pids, I don't think
> there is some universal way (read: a bottleneck) to filter all accesses.

Something like this is done for containers, but I agree with you.

> And the award is not too high to bother.

Yes, perhaps, and it'd be difficult to avoid timing leaks.

Anyhow, this would be a separate task. Let's deal with the filesystems
first, and then proceed with other hardening measures already
implemented in patches and needing proper submission upstream.

Alexander