linux-kernel - Re: [PATCH] IMA: Turn IMA_MEASURE_ASYMMETRIC

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: <1579723379.5182.130.camel@linux.ibm.com>
Date:   Wed, 22 Jan 2020 15:02:59 -0500
From:   Mimi Zohar <zohar@...ux.ibm.com>
To:     Lakshmi Ramasubramanian <nramas@...ux.microsoft.com>,
        James Bottomley <James.Bottomley@...senPartnership.com>,
        linux-integrity@...r.kernel.org
Cc:     sashal@...nel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH] IMA: Turn IMA_MEASURE_ASYMMETRIC_KEYS off by default

On Tue, 2020-01-21 at 12:38 -0800, Lakshmi Ramasubramanian wrote:
> On 1/21/2020 11:52 AM, James Bottomley wrote:
> 
> >> - really small devices/sensors being able to queue certificates
> > 
> > seems like the answer to this one would be don't queue.  I realise it's
> > after the submit design, but what about measuring when the key is added
> > if there's a policy otherwise measure the keyring when the policy is
> > added ... that way no queueing.
> 
> Without the "deferred key processing" changes, only keys added at 
> runtime were measured (if policy permitted).
> 
> "deferred key processing" enabled queuing keys added early in the boot 
> process and measured them when the policy is loaded.
> 
> We can make this (the queuing) optional through a config, but leave the 
> runtime key measurement auto-enabled (as is the config 
> IMA_MEASURE_ASYMMETRIC_KEYS now).

Thanks, Lakshmi.  This requires moving the code around.  Instead of
doing this on the current code base, I suggest posting a v9 version of
the entire "IMA: Deferred measurement of keys".

I suggest making the switch from spinlock to mutex, as you had it
originally, before posting v9.  The commit history will then be a lot
cleaner.

thanks,

Mimi