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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 EBA33C10F11 for ; Wed, 24 Apr 2019 17:35:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD27F218B0 for ; Wed, 24 Apr 2019 17:35:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556127308; bh=B9iZMpWju9Y9ei2xE33LIsTj7fYgP4CcfWfUNxBJBhc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ml5qcRSSouWoccsvpGg1t7z3MUHVXa/ROduFpPW2P22xJirfDXkr8/9Wtnx504d7I 8DMRYd/wErdtWjMTxUchKzmfOaNEHmr+08XuY3wq1d98w0TFxYP5iA1gbHKT1F0OOY pHOerqc6GzSgPiGAlSy8b33CKBk55e5IlmP5MmeI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391829AbfDXRfH (ORCPT ); Wed, 24 Apr 2019 13:35:07 -0400 Received: from mail.kernel.org ([198.145.29.99]:33840 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391190AbfDXRfB (ORCPT ); Wed, 24 Apr 2019 13:35:01 -0400 Received: from localhost (62-193-50-229.as16211.net [62.193.50.229]) (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 8518820675; Wed, 24 Apr 2019 17:35:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556127301; bh=B9iZMpWju9Y9ei2xE33LIsTj7fYgP4CcfWfUNxBJBhc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=egSmT1E3wOnNlW+mlUL03+qOQLH7XGY4z3+Rp51Wc+npUvlbid3zr309D0FSPqbFZ takqx7KLz1IeN0z/71jFy57qWOZZ/oAvwsECPHWdvcgTschg8gb6zxQvQK9zfAxs5O CDuK9fC/T209jFyU/iB4Bs0ySO6YI/mGpg0CiLSA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kevin Darbyshire-Bryant , =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Subject: [PATCH 5.0 040/115] sch_cake: Make sure we can write the IP header before changing DSCP bits Date: Wed, 24 Apr 2019 19:09:36 +0200 Message-Id: <20190424170927.393636942@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190424170924.797924502@linuxfoundation.org> References: <20190424170924.797924502@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: Toke Høiland-Jørgensen [ Upstream commit c87b4ecdbe8db27867a7b7f840291cd843406bd7 ] There is not actually any guarantee that the IP headers are valid before we access the DSCP bits of the packets. Fix this using the same approach taken in sch_dsmark. Reported-by: Kevin Darbyshire-Bryant Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Greg Kroah-Hartman --- net/sched/sch_cake.c | 11 +++++++++++ 1 file changed, 11 insertions(+) --- a/net/sched/sch_cake.c +++ b/net/sched/sch_cake.c @@ -1524,16 +1524,27 @@ static void cake_wash_diffserv(struct sk static u8 cake_handle_diffserv(struct sk_buff *skb, u16 wash) { + int wlen = skb_network_offset(skb); u8 dscp; switch (tc_skb_protocol(skb)) { case htons(ETH_P_IP): + wlen += sizeof(struct iphdr); + if (!pskb_may_pull(skb, wlen) || + skb_try_make_writable(skb, wlen)) + return 0; + dscp = ipv4_get_dsfield(ip_hdr(skb)) >> 2; if (wash && dscp) ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, 0); return dscp; case htons(ETH_P_IPV6): + wlen += sizeof(struct ipv6hdr); + if (!pskb_may_pull(skb, wlen) || + skb_try_make_writable(skb, wlen)) + return 0; + dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2; if (wash && dscp) ipv6_change_dsfield(ipv6_hdr(skb), INET_ECN_MASK, 0);