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=-5.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 4F623C433E1 for ; Mon, 27 Jul 2020 09:50:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2928B20672 for ; Mon, 27 Jul 2020 09:50:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727091AbgG0Jur (ORCPT ); Mon, 27 Jul 2020 05:50:47 -0400 Received: from a.mx.secunet.com ([62.96.220.36]:44132 "EHLO a.mx.secunet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726196AbgG0Juq (ORCPT ); Mon, 27 Jul 2020 05:50:46 -0400 Received: from localhost (localhost [127.0.0.1]) by a.mx.secunet.com (Postfix) with ESMTP id 64AA420561; Mon, 27 Jul 2020 11:50:44 +0200 (CEST) X-Virus-Scanned: by secunet Received: from a.mx.secunet.com ([127.0.0.1]) by localhost (a.mx.secunet.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ufs28DryHkk0; Mon, 27 Jul 2020 11:50:44 +0200 (CEST) Received: from cas-essen-01.secunet.de (201.40.53.10.in-addr.arpa [10.53.40.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by a.mx.secunet.com (Postfix) with ESMTPS id 01B4920482; Mon, 27 Jul 2020 11:50:44 +0200 (CEST) Received: from mbx-essen-01.secunet.de (10.53.40.197) by cas-essen-01.secunet.de (10.53.40.201) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Mon, 27 Jul 2020 11:50:43 +0200 Received: from gauss2.secunet.de (10.182.7.193) by mbx-essen-01.secunet.de (10.53.40.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1979.3; Mon, 27 Jul 2020 11:50:43 +0200 Received: by gauss2.secunet.de (Postfix, from userid 1000) id 671043184651; Mon, 27 Jul 2020 11:50:43 +0200 (CEST) Date: Mon, 27 Jul 2020 11:50:43 +0200 From: Steffen Klassert To: Cong Wang CC: B K Karthik , Herbert Xu , "David S. Miller" , Alexey Kuznetsov , Hideaki YOSHIFUJI , Jakub Kicinski , "Linux Kernel Network Developers" , LKML , Greg KH , , Subject: Re: [PATCH v2] net: ipv6: fix use-after-free Read in __xfrm6_tunnel_spi_lookup Message-ID: <20200727095043.GA20687@gauss3.secunet.de> References: <20200726030855.q6dfjekazfzl5usw@pesu.pes.edu> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-ClientProxiedBy: cas-essen-02.secunet.de (10.53.40.202) To mbx-essen-01.secunet.de (10.53.40.197) X-EXCLAIMER-MD-CONFIG: 2c86f778-e09b-4440-8b15-867914633a10 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jul 25, 2020 at 10:35:12PM -0700, Cong Wang wrote: > On Sat, Jul 25, 2020 at 8:09 PM B K Karthik wrote: > > @@ -103,10 +103,10 @@ static int __xfrm6_tunnel_spi_check(struct net *net, u32 spi) > > { > > struct xfrm6_tunnel_net *xfrm6_tn = xfrm6_tunnel_pernet(net); > > struct xfrm6_tunnel_spi *x6spi; > > - int index = xfrm6_tunnel_spi_hash_byspi(spi); > > + int index = xfrm6_tunnel_spi_hash_byaddr((const xfrm_address_t *)spi); > > > > hlist_for_each_entry(x6spi, > > - &xfrm6_tn->spi_byspi[index], > > + &xfrm6_tn->spi_byaddr[index], > > list_byspi) { > > if (x6spi->spi == spi) > > How did you convince yourself this is correct? This lookup is still > using spi. :) This can not be correct, it takes a u32 spi value and casts it to a pointer to an IP address.