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 4F1C5C282C4 for ; Mon, 4 Feb 2019 10:40:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1352E2087C for ; Mon, 4 Feb 2019 10:40:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549276853; bh=d5chEOaRnzH6BtINVqCVQZ+N1dYGC278DUab1zxGoCc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jq5VmxLNqCKkxjgokvgmcHqXflEMYg9uJYnSVV+gkeumCrgSWXWPGFO39mBDvs6QR kGEO4vFrh04A5q+UiEGZhKynhiQnLECcg2DqiFULUNzjVFJBL9yQv92ju3TjnyZEbk Kq7AM+e6Ul6ok3xKF9ei8mFiWUTpEM3nruV4cCDM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729142AbfBDKkv (ORCPT ); Mon, 4 Feb 2019 05:40:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:38814 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729057AbfBDKks (ORCPT ); Mon, 4 Feb 2019 05:40:48 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 749BE2070C; Mon, 4 Feb 2019 10:40:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1549276847; bh=d5chEOaRnzH6BtINVqCVQZ+N1dYGC278DUab1zxGoCc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zH53IhkIOFvBi5KE2J9Jbhwj85nwoxbaPbd1gCpTG3QkITXaxVuJL8lFXEW16KXbI Nt7InutjCZuJIVr1yyZSy1HgLlqzRtg9+ltJk9Pd6WlO1vlcT54XDhrXTm4mUTszLm PHOTERbxmnoqrw7Nb7VxRM492b3DqqKGA9cCEFxo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Guillaume Nault , Jacob Wen , "David S. Miller" Subject: [PATCH 4.4 35/65] l2tp: copy 4 more bytes to linear part if necessary Date: Mon, 4 Feb 2019 11:36:28 +0100 Message-Id: <20190204103616.803344405@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190204103610.583715954@linuxfoundation.org> References: <20190204103610.583715954@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore 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 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jacob Wen [ Upstream commit 91c524708de6207f59dd3512518d8a1c7b434ee3 ] The size of L2TPv2 header with all optional fields is 14 bytes. l2tp_udp_recv_core only moves 10 bytes to the linear part of a skb. This may lead to l2tp_recv_common read data outside of a skb. This patch make sure that there is at least 14 bytes in the linear part of a skb to meet the maximum need of l2tp_udp_recv_core and l2tp_recv_common. The minimum size of both PPP HDLC-like frame and Ethernet frame is larger than 14 bytes, so we are safe to do so. Also remove L2TP_HDR_SIZE_NOSEQ, it is unused now. Fixes: fd558d186df2 ("l2tp: Split pppol2tp patch into separate l2tp and ppp parts") Suggested-by: Guillaume Nault Signed-off-by: Jacob Wen Acked-by: Guillaume Nault Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/l2tp/l2tp_core.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/net/l2tp/l2tp_core.c +++ b/net/l2tp/l2tp_core.c @@ -83,8 +83,7 @@ #define L2TP_SLFLAG_S 0x40000000 #define L2TP_SL_SEQ_MASK 0x00ffffff -#define L2TP_HDR_SIZE_SEQ 10 -#define L2TP_HDR_SIZE_NOSEQ 6 +#define L2TP_HDR_SIZE_MAX 14 /* Default trace flags */ #define L2TP_DEFAULT_DEBUG_FLAGS 0 @@ -860,7 +859,7 @@ static int l2tp_udp_recv_core(struct l2t __skb_pull(skb, sizeof(struct udphdr)); /* Short packet? */ - if (!pskb_may_pull(skb, L2TP_HDR_SIZE_SEQ)) { + if (!pskb_may_pull(skb, L2TP_HDR_SIZE_MAX)) { l2tp_info(tunnel, L2TP_MSG_DATA, "%s: recv short packet (len=%d)\n", tunnel->name, skb->len);