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 A8F6BC433DF for ; Mon, 1 Jun 2020 18:19:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AC522068D for ; Mon, 1 Jun 2020 18:19:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035589; bh=UKca6Vmt0hmdfqCKi6/7uixcWxyqVdBAMMZHI2WyIZY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KMQF8XQxcDh24mXKkUwTApToFmIDxRwtH07SHN/x4k3ADZI/ihaH1y1NODAoMu88y mEvexwnz9C18/zG3jszapYe+wc9DfIAldNLEybDdKMt1uJwwG7IluU82Dunddva8ja IV4anE/W8kvDVLLd6hDIg671deu15DB2U/oWy40o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731614AbgFASTs (ORCPT ); Mon, 1 Jun 2020 14:19:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:37558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731740AbgFASQp (ORCPT ); Mon, 1 Jun 2020 14:16:45 -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 A73C22068D; Mon, 1 Jun 2020 18:16:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591035404; bh=UKca6Vmt0hmdfqCKi6/7uixcWxyqVdBAMMZHI2WyIZY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h9Mt2+f9I5ZzcCW59oOHf+dGqxQH67nDdOrHhREEMI6b+QJGLRlfMQDbKMEKThSUM Q6YmQCnfObjTL72HbHtCxH2WKesO65DkNweNEEpnUNPAg9qgjAyRsMQ/jxsD38r0eX UBJGVdp5Fk9yqzx0U7DaNSiBUfgDf0xNKt+a16Dc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xin Long , Steffen Klassert Subject: [PATCH 5.6 145/177] xfrm: do pskb_pull properly in __xfrm_transport_prep Date: Mon, 1 Jun 2020 19:54:43 +0200 Message-Id: <20200601174100.537402774@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200601174048.468952319@linuxfoundation.org> References: <20200601174048.468952319@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: Xin Long commit 06a0afcfe2f551ff755849ea2549b0d8409fd9a0 upstream. For transport mode, when ipv6 nexthdr is set, the packet format might be like: ---------------------------------------------------- | | dest | | | | ESP | ESP | | IP6 hdr| opts.| ESP | TCP | Data | Trailer | ICV | ---------------------------------------------------- and in __xfrm_transport_prep(): pskb_pull(skb, skb->mac_len + sizeof(ip6hdr) + x->props.header_len); it will pull the data pointer to the wrong position, as it missed the nexthdrs/dest opts. This patch is to fix it by using: pskb_pull(skb, skb_transport_offset(skb) + x->props.header_len); as we can be sure transport_header points to ESP header at that moment. It also fixes a panic when packets with ipv6 nexthdr are sent over esp6 transport mode: [ 100.473845] kernel BUG at net/core/skbuff.c:4325! [ 100.478517] RIP: 0010:__skb_to_sgvec+0x252/0x260 [ 100.494355] Call Trace: [ 100.494829] skb_to_sgvec+0x11/0x40 [ 100.495492] esp6_output_tail+0x12e/0x550 [esp6] [ 100.496358] esp6_xmit+0x1d5/0x260 [esp6_offload] [ 100.498029] validate_xmit_xfrm+0x22f/0x2e0 [ 100.499604] __dev_queue_xmit+0x589/0x910 [ 100.502928] ip6_finish_output2+0x2a5/0x5a0 [ 100.503718] ip6_output+0x6c/0x120 [ 100.505198] xfrm_output_resume+0x4bf/0x530 [ 100.508683] xfrm6_output+0x3a/0xc0 [ 100.513446] inet6_csk_xmit+0xa1/0xf0 [ 100.517335] tcp_sendmsg+0x27/0x40 [ 100.517977] sock_sendmsg+0x3e/0x60 [ 100.518648] __sys_sendto+0xee/0x160 Fixes: c35fe4106b92 ("xfrm: Add mode handlers for IPsec on layer 2") Signed-off-by: Xin Long Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_device.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) --- a/net/xfrm/xfrm_device.c +++ b/net/xfrm/xfrm_device.c @@ -25,12 +25,10 @@ static void __xfrm_transport_prep(struct struct xfrm_offload *xo = xfrm_offload(skb); skb_reset_mac_len(skb); - pskb_pull(skb, skb->mac_len + hsize + x->props.header_len); - - if (xo->flags & XFRM_GSO_SEGMENT) { - skb_reset_transport_header(skb); + if (xo->flags & XFRM_GSO_SEGMENT) skb->transport_header -= x->props.header_len; - } + + pskb_pull(skb, skb_transport_offset(skb) + x->props.header_len); } static void __xfrm_mode_tunnel_prep(struct xfrm_state *x, struct sk_buff *skb,