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 F1385C35242 for ; Fri, 24 Jan 2020 14:24:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BDCF72077C for ; Fri, 24 Jan 2020 14:24:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579875876; bh=vJS8x5vAhv5+CbfqIyNvJ4Xv6cnGxwPpgEtFwP/weY0=; h=From:To:Cc:Subject:Date:List-ID:From; b=QOFb6JcgVbRYVfDgg8F5LTRVbzai5DkAenTKRczrnrSxwvJg5Q01ol8Vx1nyJbIKR nTUyKCyNH8jzLTST/if3k237dYD60XOcD9ery30BoMMBhqkcG6XgOzs114S9gkoK4O 2FyWiZYLCX6uwnGcKoRyxSoStIE4Whg1L4a2L9Wk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729606AbgAXOWE (ORCPT ); Fri, 24 Jan 2020 09:22:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:44038 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405410AbgAXOWA (ORCPT ); Fri, 24 Jan 2020 09:22:00 -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 05C3121556; Fri, 24 Jan 2020 14:21:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579875719; bh=vJS8x5vAhv5+CbfqIyNvJ4Xv6cnGxwPpgEtFwP/weY0=; h=From:To:Cc:Subject:Date:From; b=A5Tx7pAvIIMfrtFpFjq+MobevJOooo/HMvgQFqxumfxcnoHh/nAo7DQlUtbHLpKhg 7KV6dhQipuqMEty5K2GlS9PI53XoYUtrJ4YWRd52q3MqbkS6EPYr5yy78NE/Had/5a +iFyOrR1Upa05kWyGoDZqAxEHOR+HVurf9U+bbkM= 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 4.9 01/18] batman-adv: Fix DAT candidate selection on little endian systems Date: Fri, 24 Jan 2020 09:21:40 -0500 Message-Id: <20200124142157.30931-1-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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 df7c6a0801885..3b440b8d7c052 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -242,6 +242,7 @@ 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; @@ -251,7 +252,8 @@ 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