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 X-Spam-Level: X-Spam-Status: No, score=-10.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0469C43441 for ; Thu, 29 Nov 2018 06:01:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 65317208E7 for ; Thu, 29 Nov 2018 06:01:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="dArobZo+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 65317208E7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729470AbeK2RGA (ORCPT ); Thu, 29 Nov 2018 12:06:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:41702 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727767AbeK2RF7 (ORCPT ); Thu, 29 Nov 2018 12:05:59 -0500 Received: from sasha-vm.mshome.net (unknown [37.142.5.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9560821104; Thu, 29 Nov 2018 06:01:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543471308; bh=3pjTNHMSJIv3ge0q4+UT4yfiTSzTxwDGpR82iYL29Ro=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dArobZo+xJYjhscaGMshJCAlRGDJw/3LOdbDi98C92rDgXu29AaB20f2jAtvbr1jW k2KTZO2xKe6bp1BsmO9diHqm+h0g269Os54/aLd2ngeOEgL1qQMzvVMl3wLKmPyGB1 tLXDMt7a3FvdGn64R7DpFw0FoihHCw+SnXAK+JhQ= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Sven Eckelmann , Simon Wunderlich , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 08/35] batman-adv: Use explicit tvlv padding for ELP packets Date: Thu, 29 Nov 2018 01:00:42 -0500 Message-Id: <20181129060110.159878-8-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181129060110.159878-1-sashal@kernel.org> References: <20181129060110.159878-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Sven Eckelmann [ Upstream commit f4156f9656feac21f4de712fac94fae964c5d402 ] The announcement messages of batman-adv COMPAT_VERSION 15 have the possibility to announce additional information via a dynamic TVLV part. This part is optional for the ELP packets and currently not parsed by the Linux implementation. Still out-of-tree versions are using it to transport things like neighbor hashes to optimize the rebroadcast behavior. Since the ELP broadcast packets are smaller than the minimal ethernet packet, it often has to be padded. This is often done (as specified in RFC894) with octets of zero and thus work perfectly fine with the TVLV part (making it a zero length and thus empty). But not all ethernet compatible hardware seems to follow this advice. To avoid ambiguous situations when parsing the TVLV header, just force the 4 bytes (TVLV length + padding) after the required ELP header to zero. Fixes: d6f94d91f766 ("batman-adv: ELP - adding basic infrastructure") Reported-by: Linus Lüssing Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin --- net/batman-adv/bat_v_elp.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c index e92dfedccc16..fbc132f4670e 100644 --- a/net/batman-adv/bat_v_elp.c +++ b/net/batman-adv/bat_v_elp.c @@ -338,19 +338,21 @@ static void batadv_v_elp_periodic_work(struct work_struct *work) */ int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface) { + static const size_t tvlv_padding = sizeof(__be32); struct batadv_elp_packet *elp_packet; unsigned char *elp_buff; u32 random_seqno; size_t size; int res = -ENOMEM; - size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN; + size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN + tvlv_padding; hard_iface->bat_v.elp_skb = dev_alloc_skb(size); if (!hard_iface->bat_v.elp_skb) goto out; skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN); - elp_buff = skb_put_zero(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN); + elp_buff = skb_put_zero(hard_iface->bat_v.elp_skb, + BATADV_ELP_HLEN + tvlv_padding); elp_packet = (struct batadv_elp_packet *)elp_buff; elp_packet->packet_type = BATADV_ELP; -- 2.17.1