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,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 B2AFCC28CBC for ; Thu, 30 Apr 2020 13:59:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8308C2063A for ; Thu, 30 Apr 2020 13:59:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588255150; bh=NjaUgs4ZaiThjKvIDR+GLSopQIjvJX6ZX4LDx59JXi0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=A3ZU0uG76Zj9Ubc/6jW2YkvoWEJE867ITJQh50blbdFK2TCrAaBn614Ic7ds2q2lE fD/OrRCnaMSAdzIRnrWcPPsPFX6/JUVkOynuetoJeHINeCfCnFkhlLfXLHWTreGBYe Zl6YWWdmw9Xcw12B35aSizARbCvVEK4ay5Y0hQb8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729338AbgD3N7J (ORCPT ); Thu, 30 Apr 2020 09:59:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:37018 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728800AbgD3Nya (ORCPT ); Thu, 30 Apr 2020 09:54:30 -0400 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 9A03F24953; Thu, 30 Apr 2020 13:54:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588254870; bh=NjaUgs4ZaiThjKvIDR+GLSopQIjvJX6ZX4LDx59JXi0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PnTh6wMWuyhenk5VtqmJRYbYvHPsZlF5jSpS7dT4JX7PFyhLuDF5hZuMA+xHQwrMZ 6SXAHq6WqTmAmtgVhvPM0YAvAJK4jp5lcXQF6XiTOriMATi1ojkPyZhckzmkOGVScl E6FFyO6f4a1UjqmYYEzcWd7rS519zaPht+X2snF0= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Taehee Yoo , "David S . Miller" , Sasha Levin , netdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 25/27] macsec: avoid to set wrong mtu Date: Thu, 30 Apr 2020 09:54:00 -0400 Message-Id: <20200430135402.20994-25-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200430135402.20994-1-sashal@kernel.org> References: <20200430135402.20994-1-sashal@kernel.org> 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: 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: Sasha Levin --- drivers/net/macsec.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c index 5959e8817a1b8..926e2eb528fd4 100644 --- a/drivers/net/macsec.c +++ b/drivers/net/macsec.c @@ -3209,11 +3209,11 @@ static int macsec_newlink(struct net *net, struct net_device *dev, 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; @@ -3229,7 +3229,11 @@ static int macsec_newlink(struct net *net, struct net_device *dev, 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) -- 2.20.1