LWN.net Logo

Re: [PATCH net-next 0/6] TCP connection repair (v4)

From:  David Miller <davem-AT-davemloft.net>
To:  xemul-AT-parallels.com
Subject:  Re: [PATCH net-next 0/6] TCP connection repair (v4)
Date:  Sat, 21 Apr 2012 15:53:54 -0400 (EDT)
Message-ID:  <20120421.155354.769351486098851306.davem@davemloft.net>
Cc:  netdev-AT-vger.kernel.org
Archive-link:  Article, Thread

From: Pavel Emelyanov <xemul@parallels.com>
Date: Thu, 19 Apr 2012 17:38:58 +0400

> Attempt #4 with an API for TCP connection recreation (previous one is
> at http://lists.openwall.net/netdev/2012/03/28/84) re-based on the
> today's net-next tree.
> 
> Changes since v3:
> 
> * Added repair for TCP options negotiated during 3WHS process, pointed
>   out by Li Yu. The explanation of how this happens is in patch #6.
> 
> * Named constant for sk_reuse values as proposed by Ben Hutching.
> 
> * Off-by-one in repair-queue sockoption caught by Ben.

All applied to net-next, nice work.

Please make the following fix for me.  The option recovery code will
result in unaligned accesses, for example you'll do a byte aligned
get_user() for the u16 MSS object in many cases, and this will trap
and cpus such as sparc.

Either add a padding facility or pass more structured data into the
socket option.

Thanks.


(Log in to post comments)

Copyright © 2012, Eklektix, Inc.
Comments and public postings are copyrighted by their creators.
Linux is a registered trademark of Linus Torvalds