Re: [Qemu-discuss] [kubevirt-dev] Re: Converting qcow2 image on the fly to raw format

[Daniel P . Berrangé]

On Thu, Jul 19, 2018 at 09:39:35PM +0100, Richard W.M. Jones wrote:
> I did the original work using AFL to fuzz qemu-img and find
> problematic images.  From that work Dan & I suggested some fairly low
> limits (10 seconds IIRC).  See:
> 
> https://bugs.launchpad.net/qemu/+bug/1462944
> https://bugs.launchpad.net/qemu/+bug/1462949
> 
> A lot more problematic images were found (at least 16), but I cannot
> recall if we filed bugs for all of them.  Note the images do not need
> to be qcow2, since someone can upload any old thing to your service
> and cause you problems.
> 
> On Thu, Jul 19, 2018 at 11:00:14PM +0300, Nir Soffer wrote:
> > The 30 seconds cpu_time time limit confuses me; it was added in:
> > https://github.com/openstack/nova/commit/011ae614d5c5fb35b2e9c22a9c4c99158f6aee20
> >
> > The patch references this bug:
> > https://bugs.launchpad.net/nova/+bug/1705340
> 
> It looks as if those original limits were too low and they have been
> increased.  For RHV I think you should go with the same settings that
> OpenStack is using.

Yes, real world usage found our original limit was too low for certain
valid images, so we increased it to 30 seconds.

Regards,
Daniel
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