Re: [PATCH] xt_TCPMSS: SYN packets are allowed to contain data

From: Jan Engelhardt
Date: Wed Jan 20 2010 - 16:42:16 EST

On Wednesday 2010-01-20 22:39, Jan Engelhardt wrote:

>On Wednesday 2010-01-20 22:21, Simon Arlott wrote:
>>The TCPMSS target is dropping SYN packets where:
>> 1) There is data, or
>> 2) The data offset makes the TCP header larger than
>> the packet.
>>Both of these result in an error level printk.
>>This change fixes the drop of SYN packets with data
>>(because the MSS option can safely be modified) and
>>passes packets with no MSS option instead of adding
>>one (which is not valid).
>Can you explain why the automatic addition of a MSS option is removed?

That is, of course, for the git log. If I followed the thread right, it
was that adding the option could exceed the MTU. Well, can't we check
for the outgoing MTU?
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