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Date: Thu, 19 Mar 2015 13:54:33 +0100
From: Hans Petter Selasky <hps@selasky.org>
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To: Emeric POUPON <emeric.poupon@stormshield.eu>, 
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Subject: Re: Fragment questions
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On 03/19/15 12:38, Emeric POUPON wrote:
> Hello,
>
> I noticed two questionable things in the fragmentation code:
> - in ip_fragment, we do not copy the flowid from the original mbuf to the fragmented mbuf. Therefore we may output very desynchronized fragments (first fragment emitted far later the second fragment, etc.)
> - in the ip_newid macro, we do "htons(V_ip_id++))" if we do not use randomized id. In multi core systems, we may emit successive packets with the same id.
>
> Both problems combined lead to bad packet reassembly on the remote host.
>
> What do you think?
>

Hi,

I think this issue is already fixed:

https://svnweb.freebsd.org/base/head/sys/netinet/ip_output.c?revision=278103&view=markup

--HPS