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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,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 66779C83007 for ; Tue, 28 Apr 2020 18:27:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 499A1208E0 for ; Tue, 28 Apr 2020 18:27:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588098468; bh=/7QBwKfyFaGo2/A27oj+RtU0qplo/5qvvtiZVFK3pMA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=X0+jPXwojUWYi6D18ljjh8LuhzY8n5Ztodq1LkpqC6UeYk6q60cD4HIdhAlvIY/JC B/+n4EVc5uu/X7HK/ao/l+/pPlyMwMuZqghYcJu4nEhB++uRezXzbmS1S54n5Wc2GR SULnDV7NJ7vx+9SBKhNp3+m1Afd0C3VpW5R+rQQU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729067AbgD1S1r (ORCPT ); Tue, 28 Apr 2020 14:27:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:39930 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729026AbgD1S1j (ORCPT ); Tue, 28 Apr 2020 14:27:39 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 77596214AF; Tue, 28 Apr 2020 18:27:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588098458; bh=/7QBwKfyFaGo2/A27oj+RtU0qplo/5qvvtiZVFK3pMA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aBxVapo+/6mSwnE9IT+hqAOSf6D/swB/IwgwwqsfCSF9SEpdzlL9kSGIYMGpmcXbk JFYB8+Hh/DZuXZjrhMNAw3jGtVcKwY3XAyGuh2BJsxtIuRGHO8h7D4vs1E/LIMnpLJ k2tv+caPsF8Fre6+LX29PIPA02Ni5xSbdZbbBOQE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Taehee Yoo , "David S. Miller" Subject: [PATCH 5.6 049/167] macsec: avoid to set wrong mtu Date: Tue, 28 Apr 2020 20:23:45 +0200 Message-Id: <20200428182231.256018680@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200428182225.451225420@linuxfoundation.org> References: <20200428182225.451225420@linuxfoundation.org> User-Agent: quilt/0.66 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: Taehee Yoo [ Upstream commit 7f327080364abccf923fa5a5b24e038eb0ba1407 ] When a macsec interface is created, the mtu is calculated with the lower interface's mtu value. If the mtu of lower interface is lower than the length, which is needed by macsec interface, macsec's mtu value will be overflowed. So, if the lower interface's mtu is too low, macsec interface's mtu should be set to 0. Test commands: ip link add dummy0 mtu 10 type dummy ip link add macsec0 link dummy0 type macsec ip link show macsec0 Before: 11: macsec0@dummy0: mtu 4294967274 After: 11: macsec0@dummy0: mtu 0 Fixes: c09440f7dcb3 ("macsec: introduce IEEE 802.1AE driver") Signed-off-by: Taehee Yoo Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/macsec.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -3658,11 +3658,11 @@ static int macsec_newlink(struct net *ne struct netlink_ext_ack *extack) { struct macsec_dev *macsec = macsec_priv(dev); + rx_handler_func_t *rx_handler; + u8 icv_len = DEFAULT_ICV_LEN; struct net_device *real_dev; - int err; + int err, mtu; sci_t sci; - u8 icv_len = DEFAULT_ICV_LEN; - rx_handler_func_t *rx_handler; if (!tb[IFLA_LINK]) return -EINVAL; @@ -3681,7 +3681,11 @@ static int macsec_newlink(struct net *ne if (data && data[IFLA_MACSEC_ICV_LEN]) icv_len = nla_get_u8(data[IFLA_MACSEC_ICV_LEN]); - dev->mtu = real_dev->mtu - icv_len - macsec_extra_len(true); + mtu = real_dev->mtu - icv_len - macsec_extra_len(true); + if (mtu < 0) + dev->mtu = 0; + else + dev->mtu = mtu; rx_handler = rtnl_dereference(real_dev->rx_handler); if (rx_handler && rx_handler != macsec_handle_frame)