Re: [BUG] Race between policy reload sidtab conversion and live conversion

From: Tyler Hicks
Date: Tue Feb 23 2021 - 17:54:29 EST


On 2021-02-23 15:50:56, Tyler Hicks wrote:
> On 2021-02-23 15:43:48, Tyler Hicks wrote:
> > I'm seeing a race during policy load while the "regular" sidtab
> > conversion is happening and a live conversion starts to take place in
> > sidtab_context_to_sid().
> >
> > We have an initial policy that's loaded by systemd ~0.6s into boot and
> > then another policy gets loaded ~2-3s into boot. That second policy load
> > is what hits the race condition situation because the sidtab is only
> > partially populated and there's a decent amount of filesystem operations
> > happening, at the same time, which are triggering live conversions.

Hmm, perhaps this is the same problem that's fixed by Ondrej's proposed
change here:

https://lore.kernel.org/selinux/20210212185930.130477-3-omosnace@xxxxxxxxxx/

I'll put these changes through a validation run (the only place that I
can seem to reproduce this crash) and see how it looks.

Tyler