netdev - Re: [PATCH net-next] openvswitch: correctly fragment packet with mpls headers

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: <20161004112804.04f25140@griffin>
Date:   Tue, 4 Oct 2016 11:28:04 +0200
From:   Jiri Benc <jbenc@...hat.com>
To:     Pravin Shelar <pshelar@....org>
Cc:     Linux Kernel Network Developers <netdev@...r.kernel.org>,
        David Ahern <dsa@...ulusnetworks.com>
Subject: Re: [PATCH net-next] openvswitch: correctly fragment packet with
 mpls headers

On Tue, 4 Oct 2016 10:24:58 +0200, Jiri Benc wrote:
> On Mon, 3 Oct 2016 11:04:46 -0700, Pravin Shelar wrote:
> > This is not correct way to detect MPLS packet. inner_protocol can be
> > set by any tunnel device for using tunnel offloads. So this would
> > break the fragmentation for encapsulated packets.
> 
> You're right, stupid me.

Actually, too little caffeine in the morning. I actually did consider
this and I believe my patch is correct. It doesn't matter what the
encapsulation is, we want to fragment the *inner* packet. And this is
exactly what this patch does.

Besides, the only case is MPLS anyway. I'm not aware of any code path
that could lead us to here, set inner protocol and not be MPLS. But
even if it is, it should work, provided the encapsulation header is
identical for all fragments and smaller than MAX_L2_LEN.

 Jiri