From mboxrd@z Thu Jan  1 00:00:00 1970
From: Patrick McHardy <kaber@trash.net>
Subject: Re: Packet Lost
Date: Mon, 19 Jun 2006 21:32:11 +0200
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To: Vasantha Kumar Puttappa <vasanthakumar@iitb.ac.in>
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Vasantha Kumar Puttappa wrote:
>>IIRC some old versions accidentally fixed up broken checksums
>>they received from userspace and this is not done anymore.
>>Do your packets have correct checksums when sent from userspace
>>to the kernel?
>>
> 
> ya my checksum calculation is correct. If my checksum is wrong, it would
> have been detected by tcpdump or ethereal(in 2.6.11-6).

No it wouldn't have been, thats what I'm saying. Old ipq versions
silently fixed broken checksums. Depending on the hook you're queueing
packets at they might get dropped locally if the checksum is corrupt.