netdev - Re: [PATCH v2] tcp: Reallocate headroom if it would overflow csum

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Thu, 11 Apr 2013 18:13:23 -0400 (EDT)
From:	David Miller <davem@...emloft.net>
To:	eric.dumazet@...il.com
Cc:	tgraf@...g.ch, netdev@...r.kernel.org,
	sergei.shtylyov@...entembedded.com, bhutchings@...arflare.com
Subject: Re: [PATCH v2] tcp: Reallocate headroom if it would overflow
 csum_start

From: Eric Dumazet <eric.dumazet@...il.com>
Date: Thu, 11 Apr 2013 15:08:52 -0700

> On Thu, 2013-04-11 at 22:57 +0200, Thomas Graf wrote:
>> If a TCP retransmission gets partially ACKed and collapsed multiple
>> times it is possible for the headroom to grow beyond 64K which will
>> overflow the 16bit skb->csum_start which is based on the start of
>> the headroom. It has been observed rarely in the wild with IPoIB due
>> to the 64K MTU.
>> 
>> Verify if the acking and collapsing resulted in a headroom exceeding
>> what csum_start can cover and reallocate the headroom if so.
>> 
>> A big thank you to Jim Foraker <foraker1@...l.gov> and the team at
>> LLNL for helping out with the investigation and testing.
>> 
>> Reported-by: Jim Foraker <foraker1@...l.gov>
>> Signed-off-by: Thomas Graf <tgraf@...g.ch>
 ...
> Acked-by: Eric Dumazet <edumazet@...gle.com>

Applied and queued up for -stable.
--
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