linux-kernel - Re: [PATCH] random / hw_random: core: start hwrng kthread also for untrusted sources

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <YxiXEJ6up6XEW8SM@zx2c4.com>
Date:   Wed, 7 Sep 2022 15:05:20 +0200
From:   "Jason A. Donenfeld" <Jason@...c4.com>
To:     Dominik Brodowski <linux@...inikbrodowski.net>
Cc:     Herbert Xu <herbert@...dor.apana.org.au>,
        linux-kernel@...r.kernel.org, linux-crypto@...r.kernel.org
Subject: Re: [PATCH] random / hw_random: core: start hwrng kthread also for
 untrusted sources

On Wed, Sep 07, 2022 at 08:54:10AM +0200, Dominik Brodowski wrote:
> Am Wed, Sep 07, 2022 at 02:34:01PM +0800 schrieb Herbert Xu:
> > Dominik Brodowski <linux@...inikbrodowski.net> wrote:
> > >
> > > diff --git a/drivers/char/random.c b/drivers/char/random.c
> > > index 79d7d4e4e582..b360ed4ece03 100644
> > > --- a/drivers/char/random.c
> > > +++ b/drivers/char/random.c
> > > @@ -867,9 +867,9 @@ void add_hwgenerator_randomness(const void *buf, size_t len, size_t entropy)
> > > 
> > >        /*
> > >         * Throttle writing to once every CRNG_RESEED_INTERVAL, unless
> > > -        * we're not yet initialized.
> > > +        * we're not yet initialized or this source isn't trusted.
> > >         */
> > > -       if (!kthread_should_stop() && crng_ready())
> > > +       if (!kthread_should_stop() && (crng_ready() || !entropy))
> > >                schedule_timeout_interruptible(CRNG_RESEED_INTERVAL);
> > > }
> > > EXPORT_SYMBOL_GPL(add_hwgenerator_randomness);
> > 
> > Couldn't you split this bit out?
> 
> I could, but this would need to get merged before the patch to the hwrng
> core gets applied. What do you (and Jason) prefer?

Just split this out and send it to me, and I'll push it early in 6.1 so
that it makes rc1, and then Herbert can apply the hwrng part separately
whenever he sees fit.

Jason