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=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 CD186C2D0DB for ; Fri, 24 Jan 2020 14:31:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 95950206F0 for ; Fri, 24 Jan 2020 14:31:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579876319; bh=k0wiRCu1a2igqDZM9EqBr14Bpm2bdspGE7jmVAYkT1g=; h=From:To:Cc:Subject:Date:List-ID:From; b=CBr2fz1yF9/YRhJeIQN3IAc8KxU7YP7ZL+Gos78HkqiF/OrQpZDQ+p4ukfpLEkFC3 /AFDOSx43/fJjUAG3pOgpvyDakjDAZGHKv29SuHGnGpjdIBDJw0Tw1fycdvfv0NjTq msfYhYhzcLMtm/yIR2vAohAaxtRWZErbM/QEDgzk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392638AbgAXOb6 (ORCPT ); Fri, 24 Jan 2020 09:31:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:41102 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404594AbgAXOUP (ORCPT ); Fri, 24 Jan 2020 09:20:15 -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 A793720838; Fri, 24 Jan 2020 14:20:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579875614; bh=k0wiRCu1a2igqDZM9EqBr14Bpm2bdspGE7jmVAYkT1g=; h=From:To:Cc:Subject:Date:From; b=lTpDDWfEzbf9lh6a5Dkea6aHf5YXb/+VPjayAJePYzLutKQFptVGF3OECfh0hLsrZ RHLhxws1gkGTFUDSLl2erEOgMVrUdb00b8Lb1pfUgnQrC7WvnbmND+GF2oj0iGvZbm qYCOubc9IO7sp2PhhdP2YCc/toFoccnY8LIfJSNM= 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 4.19 01/56] batman-adv: Fix DAT candidate selection on little endian systems Date: Fri, 24 Jan 2020 09:19:17 -0500 Message-Id: <20200124142012.29752-1-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 2895e3b26e930..f2dc7499d2663 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -251,6 +251,7 @@ 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; @@ -260,7 +261,8 @@ 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