Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751502Ab3HCKO6 (ORCPT ); Sat, 3 Aug 2013 06:14:58 -0400 Received: from forward-corp1f.mail.yandex.net ([95.108.130.40]:41254 "EHLO forward-corp1f.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751390Ab3HCKO4 (ORCPT ); Sat, 3 Aug 2013 06:14:56 -0400 Authentication-Results: smtpcorp4.mail.yandex.net; dkim=pass header.i=@yandex-team.ru Message-ID: <51FCD818.8040304@yandex-team.ru> Date: Sat, 03 Aug 2013 14:14:48 +0400 From: Roman Gushchin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: David Miller CC: eric.dumazet@gmail.com, raise.sail@gmail.com, ebiederm@xmission.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] net: check net.core.somaxconn sysctl values References: <20130801.141836.1104130035137318887.davem@davemloft.net> <1375454200-21303-1-git-send-email-klamm@yandex-team.ru> <20130802.151915.1964036907997678424.davem@davemloft.net> In-Reply-To: <20130802.151915.1964036907997678424.davem@davemloft.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1934 Lines: 56 On 03.08.2013 02:19, David Miller wrote: > From: Roman Gushchin > Date: Fri, 2 Aug 2013 18:36:40 +0400 > >> It's possible to assign an invalid value to the net.core.somaxconn >> sysctl variable, because there is no checks at all. >> >> The sk_max_ack_backlog field of the sock structure is defined as >> unsigned short. Therefore, the backlog argument in inet_listen() >> shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall >> is truncated to the somaxconn value. So, the somaxconn value shouldn't >> exceed 65535 (USHRT_MAX). >> Also, negative values of somaxconn are meaningless. >> >> before: >> $ sysctl -w net.core.somaxconn=256 >> net.core.somaxconn = 256 >> $ sysctl -w net.core.somaxconn=65536 >> net.core.somaxconn = 65536 >> $ sysctl -w net.core.somaxconn=-100 >> net.core.somaxconn = -100 >> >> after: >> $ sysctl -w net.core.somaxconn=256 >> net.core.somaxconn = 256 >> $ sysctl -w net.core.somaxconn=65536 >> error: "Invalid argument" setting key "net.core.somaxconn" >> $ sysctl -w net.core.somaxconn=-100 >> error: "Invalid argument" setting key "net.core.somaxconn" >> >> Based on a prior patch from Changli Gao. >> >> Signed-off-by: Roman Gushchin >> Reported-by: Changli Gao >> Suggested-by: Eric Dumazet >> Acked-by: Eric Dumazet > > Applied, thanks. Thank you! Regards, Roman > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/