From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0EF18C433EF for ; Thu, 28 Oct 2021 07:33:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E16F46103C for ; Thu, 28 Oct 2021 07:33:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229852AbhJ1Hfz (ORCPT ); Thu, 28 Oct 2021 03:35:55 -0400 Received: from szxga08-in.huawei.com ([45.249.212.255]:26130 "EHLO szxga08-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229626AbhJ1Hfz (ORCPT ); Thu, 28 Oct 2021 03:35:55 -0400 Received: from dggemv703-chm.china.huawei.com (unknown [172.30.72.57]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Hfy0t2pkgz1DHpx; Thu, 28 Oct 2021 15:31:26 +0800 (CST) Received: from dggpeml500006.china.huawei.com (7.185.36.76) by dggemv703-chm.china.huawei.com (10.3.19.46) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Thu, 28 Oct 2021 15:33:22 +0800 Received: from [10.174.178.240] (10.174.178.240) by dggpeml500006.china.huawei.com (7.185.36.76) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.15; Thu, 28 Oct 2021 15:33:21 +0800 Subject: Re: [PATCH net 2/3] can: j1939: j1939_can_recv(): ignore messages with invalid source address To: Oleksij Rempel CC: Robin van der Gracht , , Oleksij Rempel , , "Marc Kleine-Budde" , , Oliver Hartkopp , Jakub Kicinski , , "David S. Miller" References: <1634825057-47915-1-git-send-email-zhangchangzhong@huawei.com> <1634825057-47915-3-git-send-email-zhangchangzhong@huawei.com> <20211022102306.GB20681@pengutronix.de> <9c636d7f-70df-18c9-66ed-46eb21f4ffbb@huawei.com> <20211028065144.GE20681@pengutronix.de> From: Zhang Changzhong Message-ID: Date: Thu, 28 Oct 2021 15:33:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20211028065144.GE20681@pengutronix.de> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [10.174.178.240] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500006.china.huawei.com (7.185.36.76) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On 2021/10/28 14:51, Oleksij Rempel wrote: > Hi, > > On Mon, Oct 25, 2021 at 03:30:57PM +0800, Zhang Changzhong wrote: >> On 2021/10/22 18:23, Oleksij Rempel wrote: >>> On Thu, Oct 21, 2021 at 10:04:16PM +0800, Zhang Changzhong wrote: >>>> According to SAE-J1939-82 2015 (A.3.6 Row 2), a receiver should never >>>> send TP.CM_CTS to the global address, so we can add a check in >>>> j1939_can_recv() to drop messages with invalid source address. >>>> >>>> Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") >>>> Signed-off-by: Zhang Changzhong >>> >>> NACK. This will break Address Claiming, where first message is SA == 0xff >> >> I know that 0xfe can be used as a source address, but which message has a source >> address of 0xff? >> >> According to SAE-J1939-81 2017 4.2.2.8： >> >> The network address 255, also known as the Global address, is permitted in the >> Destination Address field of the SAE J1939 message identifier but never in the >> Source Address field. > > You are right. Thx! > > Are you using any testing frameworks? > Can you please take a look here: > https://github.com/linux-can/can-tests/tree/master/j1939 > > We are using this scripts for regression testing of some know bugs. Great! I'll run these scripts before posting patches. > >> >>> >>>> --- >>>> net/can/j1939/main.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/net/can/j1939/main.c b/net/can/j1939/main.c >>>> index 08c8606..4f1e4bb 100644 >>>> --- a/net/can/j1939/main.c >>>> +++ b/net/can/j1939/main.c >>>> @@ -75,6 +75,10 @@ static void j1939_can_recv(struct sk_buff *iskb, void *data) >>>> skcb->addr.pgn = (cf->can_id >> 8) & J1939_PGN_MAX; >>>> /* set default message type */ >>>> skcb->addr.type = J1939_TP; >>>> + if (!j1939_address_is_valid(skcb->addr.sa)) >>>> + /* ignore messages whose sa is broadcast address */ >>>> + goto done; > > Please add some warning once message here. We wont to know if something bad > is happening on the bus. Will do. Thanks for your suggestions. Regards, Changzhong > >>>> + >>>> if (j1939_pgn_is_pdu1(skcb->addr.pgn)) { >>>> /* Type 1: with destination address */ >>>> skcb->addr.da = skcb->addr.pgn; >>>> -- >>>> 2.9.5 >>>> >>>> >>>> >>> >> >> > > Regards, > Oleksij >