Re: XFS security fix never sent to -stable?

Dave Chinner
2013-12-11T04:18:09Z

On Tue, Dec 10, 2013 at 06:45:54PM -0800, Kees Cook wrote:
> On Tue, Dec 10, 2013 at 6:00 PM, Dave Chinner <david@fromorbit.com> wrote:
> > On Tue, Dec 10, 2013 at 08:10:51PM -0500, Josh Boyer wrote:
> >> On Tue, Dec 10, 2013 at 8:03 PM, Dave Chinner <david@fromorbit.com> wrote:
> >> > Security processes are not something that should be hidden away in
> >> > it's own private corner - if there's a problem upstream needs to
> >> > take action on, then direct contact with upstream is necessary. We
> >> > need to know about security issues - even ones that are classified
> >> > post-commit as security issues - so we are operating with full
> >> > knowledge of the issues in our code and the impact of our fixes....
> >>
> >> Agreed. I'm going to interpret your comments at being directed to the
> >> general audience because otherwise you're just shooting the messenger
> >> :).
> >
> > Right, they are not aimed at you - they are aimed at those on the
> > security side of the fence. I'm tired of learning about CVEs in XFS
> > code through chinese whispers and/or luck.
>
> Mostly I try to shield anyone not interested in CVEs from the boring
> process, and try to focus on just getting things marked as needing to
> go into stable. I don't think anyone needs to read the oss-security
> list if they don't want to.

Which is how is should be. ;) All I want is some kind of
notification when a CVE raised for an XFS issue. It may be telling
us something we already known, but if:

a) it has not yet been pushed upstream; or
b) it was not marked for stable kernels at commit time; or
c) don't have a fix for it yet

then it's an indication that we need to pay a little more attention
to this class of problem when we review similar fixes.

> In this case, the fix Dan sent was part of a larger collection of
> security issues reported by Nico. I think the communication error here
> was Dan accidentally forgetting to add the Cc: stable tag. But beyond
> that, it was sent to the xfs list and Cc: to security, so I'm not sure
> it's fair to say it was hidden away. :)

Right - this falls into the above category a) because of that. There
didn't appear to be any urgency because of the level of exposure of
the problem (i.e. need CAP_SYS_ADMIN to trip over it) and the fact
it's been like this for the past 10 years....

> Besides the missing Cc: stable tag, what should future patch senders
> do to call attention to an issue being a security problem at the time
> it is being reported?

Well, it may not be known at the time it's considered a security
issue, so I think that the best thing to do is make sure that when
a CVE is actually raise a note is sent to the relevant list just to
indicate 'CVE 1024-3267 has been raised for commit abcd1234
("xfs: knabgraddle the frobnozzle")'.

At least that way everyone - including XFS users - that there is an
issue that they might want to look out for and plan to upgrade their
stable kernels in the not-to-distant future...

Cheers,

Dave.
--
Dave Chinner
david@fromorbit.com