netdev
[Top] [All Lists]

Re: question about linux tcp request queue handling

To: Andi Kleen <ak@xxxxxxx>
Subject: Re: question about linux tcp request queue handling
From: Doug McNaught <doug@xxxxxxxxxxxx>
Date: 07 Jul 2003 18:25:17 -0400
Cc: "Paul Albrecht" <palbrecht@xxxxxxxxx>, niv@xxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, "netdev" <netdev@xxxxxxxxxxx>
In-reply-to: Andi Kleen's message of "07 Jul 2003 23:48:10 +0200"
References: <3F08858E.8000907@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <001a01c3441c$6fe111a0$6801a8c0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <3F08B7E2.7040208@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <000d01c3444f$e6439600$6801a8c0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <3F090A4F.10004@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <001401c344df$ccbc63c0$6801a8c0@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> <p73fzliqa91.fsf@xxxxxxxxxxxxxxxx>
Sender: netdev-bounce@xxxxxxxxxxx
User-agent: Gnus/5.0806 (Gnus v5.8.6) Emacs/20.7
Andi Kleen <ak@xxxxxxx> writes:

> "Paul Albrecht" <palbrecht@xxxxxxxxx> writes:
> 
> > This statement is inconsistent with the description of this scenario in
> > Steven's TCP/IP Illustrated.  Specifically, continuing the handshake in the
> > TCP layer, i.e., sending a syn/ack and moving to the syn_recd state, is
> > incorrect if the limit of the server's socket backlog would be exceeded.
> > How do you account for this discrepancy between linux and other
> > berkeley-derived implementations?
> 
> The 4.4BSD-Lite code described in Stevens is long outdated. All modern
> BSDs (and probably most other Unixes too) do it in a similar way to what 
> Nivedita described. The keywords are "syn flood attack" and "DoS". 

And furthermore, IIRC, the current Linux networking code is not
Berkeley-derived, though an earlier version was.

-Doug

<Prev in Thread] Current Thread [Next in Thread>