Subject: Re: [PATCH] vhost/net: length miscalculation

From: "Michael S. Tsirkin" <[email-masked]>
Date: Thu, 8 Jan 2015 10:08:29 +0200

On Wed, Jan 07, 2015 at 11:58:00PM +0300, Sergei Shtylyov wrote:
> Hello.
> 
> On 01/07/2015 11:55 AM, Michael S. Tsirkin wrote:
> 
> >commit 8b38694a2dc8b18374310df50174f1e4376d6824
> >     vhost/net: virtio 1.0 byte swap
> >had this chunk:
> >-       heads[headcount - 1].len += datalen;
> >+       heads[headcount - 1].len = cpu_to_vhost32(vq, len - datalen);
> 
> >This adds datalen with the wrong sign, causing guest panics.
> 
> >Fixes: 8b38694a2dc8b18374310df50174f1e4376d6824
> 
>    The format of this tag assumes 12-digit SHA1 hash and the commit
> description enclosed in parens and double quotes. See
> Documentation/SubmittingPatches.
> 
> >Reported-by: Alex Williamson <[email-masked]>
> >Suggested-by: Greg Kurz <[email-masked]>
> >Signed-off-by: Michael S. Tsirkin <[email-masked]>
> 
> WBR, Sergei

I pushed the patches to Linus unfortunately - there's
some urgency since many people are hitting the bug.
Will do my best to do it right next time.

-- 
MST