From patchwork Sat Oct 22 07:46:24 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sven Eckelmann X-Patchwork-Id: 16755 Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from open-mesh.org (localhost [IPv6:::1]) by open-mesh.org (Postfix) with ESMTP id 41FB9817DC; Sat, 22 Oct 2016 09:46:54 +0200 (CEST) Authentication-Results: open-mesh.org; dmarc=none header.from=narfation.org Authentication-Results: open-mesh.org; dkim=fail reason="verification failed; unprotected key" header.d=narfation.org header.i=@narfation.org header.b=HuQ7r4Ng; dkim-adsp=fail (unprotected policy); dkim-atps=neutral Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=2001:4d88:2000:7::2; helo=v3-1039.vlinux.de; envelope-from=sven@narfation.org; receiver=b.a.t.m.a.n@lists.open-mesh.org Authentication-Results: open-mesh.org; dmarc=pass header.from=narfation.org Received: from v3-1039.vlinux.de (narfation.org [IPv6:2001:4d88:2000:7::2]) by open-mesh.org (Postfix) with ESMTPS id 182A080894 for ; Sat, 22 Oct 2016 09:46:49 +0200 (CEST) Received: from sven-desktop.home.narfation.org (p200300C593CCC1F90000000000002E16.dip0.t-ipconnect.de [IPv6:2003:c5:93cc:c1f9::2e16]) by v3-1039.vlinux.de (Postfix) with ESMTPSA id 6E5381C8001; Sat, 22 Oct 2016 09:46:49 +0200 (CEST) Authentication-Results: v3-1039.vlinux.de; dmarc=none header.from=narfation.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=narfation.org; s=20121; t=1477122409; bh=CboSgPE2KJZj6VNO9qXRkLKm8lSMxPxxtmGjN89GyKw=; h=From:To:Cc:Subject:Date:From; b=HuQ7r4Ng5gKNg7wfXQoRNOSWk+R8gFdcwDT5vOq4l5ivHYnIGg7BLLb3x3DKjIfjR POXY+Pmg3ep1J7IeUCP1XZX2BgA5Q2KGViZsHyg7vMBsYSHvtaOYrRWrNxmPsfnTcj FMwBvRYEjTDjbA+gTYfyquWQw0xbZLlXchFFxUc0= From: Sven Eckelmann To: netdev@vger.kernel.org Date: Sat, 22 Oct 2016 09:46:24 +0200 Message-Id: <20161022074624.30033-1-sven@narfation.org> X-Mailer: git-send-email 2.9.3 Cc: Jarod Wilson , b.a.t.m.a.n@lists.open-mesh.org, davem@davemloft.net, linux-kernel@vger.kernel.org Subject: [B.A.T.M.A.N.] [PATCH] batman-adv: Revert "use core MTU range checking in misc drivers" X-BeenThere: b.a.t.m.a.n@lists.open-mesh.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: The list for a Better Approach To Mobile Ad-hoc Networking List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking Errors-To: b.a.t.m.a.n-bounces@lists.open-mesh.org Sender: "B.A.T.M.A.N" The maximum MTU is defined via the slave devices of an batman-adv interface. Thus it is not possible to calculate the max_mtu during the creation of the batman-adv device when no slave devices are attached. Doing so would for example break non-fragmentation setups which then (incorrectly) allow an MTU of 1500 even when underlying device cannot transport 1500 bytes + batman-adv headers. Checking the dynamically calculated max_mtu via the minimum of the slave devices MTU during .ndo_change_mtu is also used by the bridge interface. Cc: Jarod Wilson Fixes: b3e3893e1253 ("net: use core MTU range checking in misc drivers") Signed-off-by: Sven Eckelmann --- Original patch + my comment: https://patchwork.ozlabs.org/patch/684722/ I just got informed about this patch when it was already applied in net-next. So I can only ask for an revet of the batman-adv parts net/batman-adv/soft-interface.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c index 112679d..49e16b6 100644 --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -158,6 +158,17 @@ static int batadv_interface_set_mac_addr(struct net_device *dev, void *p) return 0; } +static int batadv_interface_change_mtu(struct net_device *dev, int new_mtu) +{ + /* check ranges */ + if ((new_mtu < 68) || (new_mtu > batadv_hardif_min_mtu(dev))) + return -EINVAL; + + dev->mtu = new_mtu; + + return 0; +} + /** * batadv_interface_set_rx_mode - set the rx mode of a device * @dev: registered network device to modify @@ -909,6 +920,7 @@ static const struct net_device_ops batadv_netdev_ops = { .ndo_vlan_rx_add_vid = batadv_interface_add_vid, .ndo_vlan_rx_kill_vid = batadv_interface_kill_vid, .ndo_set_mac_address = batadv_interface_set_mac_addr, + .ndo_change_mtu = batadv_interface_change_mtu, .ndo_set_rx_mode = batadv_interface_set_rx_mode, .ndo_start_xmit = batadv_interface_tx, .ndo_validate_addr = eth_validate_addr, @@ -975,7 +987,6 @@ struct net_device *batadv_softif_create(struct net *net, const char *name) dev_net_set(soft_iface, net); soft_iface->rtnl_link_ops = &batadv_link_ops; - soft_iface->max_mtu = batadv_hardif_min_mtu(soft_iface); ret = register_netdevice(soft_iface); if (ret < 0) {