Re: [PATCH] fix small DoS on connect() (was Re: BUG: Unusual TCP Connect() results.)

[Herbert Xu]

On Sun, Jun 12, 2005 at 10:34:09AM +0200, Willy Tarreau wrote:
>
> > Sorry but this patch is pointless.  If I wanted to prevent you from
> > connecting to www.kernel.org 80 and I knew your source port number
> > I'd be directly sending you fake SYN-ACK packets which will kill
> > your connection immediately.
> 
> Only if your ACK was within my SEQ window, which adds about 20 bits of
> random when my initial window is 5840. You would then need to send one
> million times more packets to achieve the same goal.

Nope, no sequence validity check is made on the SYN-ACK.
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