From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH RFC] ipv6: use stronger hash for reassembly queue hash table Date: Fri, 08 Mar 2013 06:53:06 -0800 Message-ID: <1362754386.15793.226.camel@edumazet-glaptop> References: <20130307214211.GP7941@order.stressinduktion.org> <20130308055718.GA28531@order.stressinduktion.org> <20130308130433.GB28531@order.stressinduktion.org> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, yoshfuji@linux-ipv6.org To: Hannes Frederic Sowa Return-path: Received: from mail-pa0-f51.google.com ([209.85.220.51]:48463 "EHLO mail-pa0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757848Ab3CHOxK (ORCPT ); Fri, 8 Mar 2013 09:53:10 -0500 Received: by mail-pa0-f51.google.com with SMTP id hz1so1354499pad.10 for ; Fri, 08 Mar 2013 06:53:09 -0800 (PST) In-Reply-To: <20130308130433.GB28531@order.stressinduktion.org> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, 2013-03-08 at 14:04 +0100, Hannes Frederic Sowa wrote: > Ok if I send a patch later to revert this change? What do you think about > increasing the size of the fragmentation queue hash table INETFRAGS_HASHSZ, > too? Thats because reassembly hash was so small, and number of in flight reassembly is so small anyway, that I felt not worth having so many instructions to compute a hash that is truncated to 6 bits In real life I always advocate _not_ using fragments, I dont know why so many people try to used them. No matter how you hash, a hacker can easily fill your defrag unit with not complete datagrams, so what's the point ?