netdev - Re: [PATCH net] gre: Fix MTU sizing check for gretap tunnels

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] [day] [month] [year] [list]

Date:	Fri, 12 Jul 2013 01:11:16 +0000 (UTC)
From:	Cong Wang <xiyou.wangcong@...il.com>
To:	netdev@...r.kernel.org
Subject: Re: [PATCH net] gre: Fix MTU sizing check for gretap tunnels

On Thu, 11 Jul 2013 at 20:12 GMT, Alexander Duyck <alexander.h.duyck@...el.com> wrote:
> This change fixes an MTU sizing issue seen with gretap tunnels when non-gso
> packets are sent from the interface.
>
> In my case I was able to reproduce the issue by simply sending a ping of
> 1421 bytes with the gretap interface created on a device with a standard
> 1500 mtu.
>
> This fix is based on the fact that the tunnel mtu is already adjusted by
> dev->hard_header_len so it would make sense that any packets being compared
> against that mtu should also be adjusted by hard_header_len and the tunnel
> header instead of just the tunnel header.
>


This patch indeed fixes the performance problem I reported, nice work!

Thanks for the patch, Alexander!

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html