From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Butskoy Subject: Re: Traceroute and "ping" sockets: some questions Date: Fri, 19 Aug 2011 17:56:26 +0400 Message-ID: <4E4E6B8A.1030707@odu.neva.ru> References: <4E4E46B4.9010909@odu.neva.ru> <20110819.043816.1648681777223816477.davem@davemloft.net> <4E4E4DF6.2020509@odu.neva.ru> <20110819.062249.2234872106788628654.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: netdev@vger.kernel.org Return-path: Received: from mail2.odu.neva.ru ([194.85.100.6]:34827 "EHLO mail2.odu.neva.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751685Ab1HSN42 (ORCPT ); Fri, 19 Aug 2011 09:56:28 -0400 Received: from buc.odu.neva.ru (buc.odu.neva.ru [194.85.100.33]) by mail2.odu.neva.ru (Postfix) with ESMTPA id 0379F14A8039 for ; Fri, 19 Aug 2011 17:56:26 +0400 (MSD) In-Reply-To: <20110819.062249.2234872106788628654.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: David Miller wrote: >>> Why limit? He can spam with UDP socket just as easily at any rate >>> he pleases, >>> >> Yes, but most cases such UDP is "one-way" spam (until services like >> "echo 7/udp" are enabled). >> For icmp echo, we normally receive icmp replies, hence it is >> bidirectional crap. Which was not present before. >> > Well, replace UDP with TCP syn flood. > Well. Why then there is "net/ipv4/ping_group_range" restrictions, with default values (low=1, high=0) which denies this way even for root? Regards, Dmitry