Re: [PATCH] Fix NAT TCP sequence adjustment

[Patrick McHardy <kaber@trash.net>]

Phil Oester wrote:
> On Wed, Apr 20, 2005 at 06:07:45PM +0200, Patrick McHardy wrote:
> 
>>You forget about the network, which can duplicate, delay and reorder
>>packets. If we don't handle this is it will screw up the state.
> 
> I'm aware of that, but again I claim that it is irrelevant in this case
> because the PORT commands will not be processed out of order (even if the
> data packets are), and thus the adjustments will occur sequentially.

Why wouldn't they be processed out of order by nat?

>>No, but this function should do the right thing anyway.
> 
> Agreed, but IMHO my approach is currently the best available fix for a problem
> which is affecting many people.  If further testing shows it can be improved,
> that is great -- but I certainly don't think it's any worse than the current
> broken behaviour.

I agree that the problem should be fixed ASAP. I'll do a proper fix
now - either by moving seq adjustment after NAT helpers or by adding
a flag to the skb.

Regards
Patrick