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 C7F3BC433EF for ; Thu, 14 Oct 2021 12:15:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AC26B60E96 for ; Thu, 14 Oct 2021 12:15:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231264AbhJNMRE (ORCPT ); Thu, 14 Oct 2021 08:17:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37298 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230094AbhJNMRD (ORCPT ); Thu, 14 Oct 2021 08:17:03 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6170CC061570 for ; Thu, 14 Oct 2021 05:14:58 -0700 (PDT) Received: from ptx.hi.pengutronix.de ([2001:67c:670:100:1d::c0]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mazdB-0002Q8-4c; Thu, 14 Oct 2021 14:14:41 +0200 Received: from ore by ptx.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1mazd5-0000Ck-Bp; Thu, 14 Oct 2021 14:14:35 +0200 Date: Thu, 14 Oct 2021 14:14:35 +0200 From: Oleksij Rempel To: Zhang Changzhong Cc: Robin van der Gracht , Oleksij Rempel , kernel@pengutronix.de, Oliver Hartkopp , Marc Kleine-Budde , "David S. Miller" , Jakub Kicinski , Kurt Van Dijck , Maxime Jayat , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] can: j1939: j1939_xtp_rx_rts_session_new(): abort TP less than 9 bytes Message-ID: <20211014121435.GA7427@pengutronix.de> References: <1634203601-3460-1-git-send-email-zhangchangzhong@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1634203601-3460-1-git-send-email-zhangchangzhong@huawei.com> X-Sent-From: Pengutronix Hildesheim X-URL: http://www.pengutronix.de/ X-IRC: #ptxdist @freenode X-Accept-Language: de,en X-Accept-Content-Type: text/plain X-Uptime: 14:13:58 up 238 days, 15:37, 145 users, load average: 0.23, 0.38, 0.40 User-Agent: Mutt/1.10.1 (2018-07-13) X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::c0 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 14, 2021 at 05:26:40PM +0800, Zhang Changzhong wrote: > The receiver should abort TP if 'total message size' in TP.CM_RTS and > TP.CM_BAM is less than 9 or greater than 1785 [1], but currently the > j1939 stack only checks the upper bound and the receiver will accept the > following broadcast message: > vcan1 18ECFF00 [8] 20 08 00 02 FF 00 23 01 > vcan1 18EBFF00 [8] 01 00 00 00 00 00 00 00 > vcan1 18EBFF00 [8] 02 00 FF FF FF FF FF FF > > This patch adds check for the lower bound and abort illegal TP. > > [1] SAE-J1939-82 A.3.4 Row 2 and A.3.6 Row 6. > > Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol") > Signed-off-by: Zhang Changzhong Acked-by: Oleksij Rempel Thank you! > --- > net/can/j1939/j1939-priv.h | 1 + > net/can/j1939/transport.c | 2 ++ > 2 files changed, 3 insertions(+) > > diff --git a/net/can/j1939/j1939-priv.h b/net/can/j1939/j1939-priv.h > index f6df208..16af1a7 100644 > --- a/net/can/j1939/j1939-priv.h > +++ b/net/can/j1939/j1939-priv.h > @@ -330,6 +330,7 @@ int j1939_session_activate(struct j1939_session *session); > void j1939_tp_schedule_txtimer(struct j1939_session *session, int msec); > void j1939_session_timers_cancel(struct j1939_session *session); > > +#define J1939_MIN_TP_PACKET_SIZE 9 > #define J1939_MAX_TP_PACKET_SIZE (7 * 0xff) > #define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff) > > diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c > index bb5c4b8..b685d31 100644 > --- a/net/can/j1939/transport.c > +++ b/net/can/j1939/transport.c > @@ -1609,6 +1609,8 @@ j1939_session *j1939_xtp_rx_rts_session_new(struct j1939_priv *priv, > abort = J1939_XTP_ABORT_FAULT; > else if (len > priv->tp_max_packet_size) > abort = J1939_XTP_ABORT_RESOURCE; > + else if (len < J1939_MIN_TP_PACKET_SIZE) > + abort = J1939_XTP_ABORT_FAULT; > } > > if (abort != J1939_XTP_NO_ABORT) { > -- > 2.9.5 > > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |