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Re: skb_checksum_help

To: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Subject: Re: skb_checksum_help
From: David Coulson <david@xxxxxxxxxxxxxxxx>
Date: Tue, 25 Jan 2005 09:16:37 -0500
Cc: Thomas Graf <tgraf@xxxxxxx>, "David S. Miller" <davem@xxxxxxxxxxxxx>, kaber@xxxxxxxxx, netdev@xxxxxxxxxxx
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Herbert Xu wrote:

OK, I think I've found the problem.  It's a totally innocuous bug
in ip_fragment/ip6_fragment.  When we're in the fast path and use
the pre-existing frag_list skb's, we forgot to clear ip_summed.

Okay - I applied Herbert's patch to my kernels and it all looks good now. Thomas showed me how to generate fragged packets using hping2 (handy tool!) and replicate the kernel failure.

I slammed it with hping2 for a while, and didn't experience any kernel errors or see any debug information from previous patches. Everything is working as it should be, and I verified I saw the fragged packets in tcpdump to make sure they were being routed properly.

:-)

David

--
David J. Coulson
email: david@xxxxxxxxxxxxxxxx
web: http://www.davidcoulson.net/
phone: (216) 920-3100 / (216) 258-4942

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