From: Andi Kleen Subject: Re: [PATCH 1/2] [IPV4] UDP: Always checksum even if without socket filter Date: Sat, 17 Nov 2007 14:18:46 +0100 Message-ID: References: <473D19EC.6030903@cn.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Herbert Xu , davem@davemloft.net, netdev@vger.kernel.org To: Wang Chen Return-path: Received: from ns1.suse.de ([195.135.220.2]:50674 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751928AbXKQNSs (ORCPT ); Sat, 17 Nov 2007 08:18:48 -0500 In-Reply-To: <473D19EC.6030903@cn.fujitsu.com> (Wang Chen's message of "Fri\, 16 Nov 2007 12\:17\:48 +0800") Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Wang Chen writes: > Herbert Xu said the following on 2007-11-16 12:11: >> Wang Chen wrote: >>> So, I think the checksum in udp_queue_rcv_skb() actually does >>> the work, not that in udp_recvmsg() and udp_poll(). >>> >>> If I am wrong, please point out. >> >> We may have a bug in the accounting area. Check the recent >> patch made to UDP/IPv6 which is probably needed here as well. >> > > Like dave said, decrementing the InDataGrams in this case is an > option. > I will check the same place of UDP/IPv6. And like Benny pointed out it's probably a bad idea because decrementing counters will be an unexpected ABI change for monitoring programs who have no other way to detect overflow. -Andi