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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 909F9C35242 for ; Fri, 24 Jan 2020 14:22:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5D2492468F for ; Fri, 24 Jan 2020 14:22:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579875747; bh=JndqAaWRMQuy3nm1R4jhkd9XYrsf/vtVro7uCNEVFKM=; h=From:To:Cc:Subject:Date:List-ID:From; b=ffSQ3ii3C7HRBlSosCBHW1eVSGwVlwD/1puDHwX5YxEzWJ4vOZKhyve2U47XiP4+m 01QyvW6kWrEtyJhe8pgCsj/MRIaG1z3MS2ZFD1w3sHjk+Gi8JPCG1hTOAFd81RXwkQ aLnuAOPBzBGf2OyFNhTYX+pCz4wgub6x5HxmpOe0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2405424AbgAXOWZ (ORCPT ); Fri, 24 Jan 2020 09:22:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:44462 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392334AbgAXOWX (ORCPT ); Fri, 24 Jan 2020 09:22:23 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 6280222464; Fri, 24 Jan 2020 14:22:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579875743; bh=JndqAaWRMQuy3nm1R4jhkd9XYrsf/vtVro7uCNEVFKM=; h=From:To:Cc:Subject:Date:From; b=KI/GcPLd6KfqXV9yU5S80WXJbymr8HUI7P/pB1VyFJM3NuPllbY6Lc/0NAhhrw3MI vRFRz5KND5iBuTf0b88ErKMfHU+wtPDnF0AtEDdNPFa9OiY0Of/RJ3C3ECYgpBcfTA c0PNvEWIespWB5mK+7IDIbbcjktTEendDzmkPPWo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Sven Eckelmann , Simon Wunderlich , Sasha Levin , b.a.t.m.a.n@lists.open-mesh.org, netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 1/9] batman-adv: Fix DAT candidate selection on little endian systems Date: Fri, 24 Jan 2020 09:22:13 -0500 Message-Id: <20200124142221.31201-1-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sven Eckelmann [ Upstream commit 4cc4a1708903f404d2ca0dfde30e71e052c6cbc9 ] The distributed arp table is using a DHT to store and retrieve MAC address information for an IP address. This is done using unicast messages to selected peers. The potential peers are looked up using the IP address and the VID. While the IP address is always stored in big endian byte order, this is not the case of the VID. It can (depending on the host system) either be big endian or little endian. The host must therefore always convert it to big endian to ensure that all devices calculate the same peers for the same lookup data. Fixes: be1db4f6615b ("batman-adv: make the Distributed ARP Table vlan aware") Signed-off-by: Sven Eckelmann Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin --- net/batman-adv/distributed-arp-table.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index c2dff7c6e9607..76808c5e81836 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -226,6 +226,7 @@ static u32 batadv_hash_dat(const void *data, u32 size) u32 hash = 0; const struct batadv_dat_entry *dat = data; const unsigned char *key; + __be16 vid; u32 i; key = (const unsigned char *)&dat->ip; @@ -235,7 +236,8 @@ static u32 batadv_hash_dat(const void *data, u32 size) hash ^= (hash >> 6); } - key = (const unsigned char *)&dat->vid; + vid = htons(dat->vid); + key = (__force const unsigned char *)&vid; for (i = 0; i < sizeof(dat->vid); i++) { hash += key[i]; hash += (hash << 10); -- 2.20.1