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 27F7FC282C2 for ; Wed, 13 Feb 2019 18:48:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F1A8D222D1 for ; Wed, 13 Feb 2019 18:48:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550083686; bh=YaLgMlk5ulSiJtjiRMII83+nVG+KDv2bpWqVRxluOBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=D+XesHyC+Q90LIAGDwZR4UlefoAeYDagGpJ1V7QedXCzBVd6FwlB84hSt0LcKRQL4 +n6gM8bZ7d6eUW8r2Q4KoFip2r/5x1S4G3tUSC10gaV+t7HIOBYGuILFhHFlbZLakM XIS6RYXP4YJ5Q7w4xPD9swMgctSefh1qJrCeG8sE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406248AbfBMSsE (ORCPT ); Wed, 13 Feb 2019 13:48:04 -0500 Received: from mail.kernel.org ([198.145.29.99]:45364 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406523AbfBMSqt (ORCPT ); Wed, 13 Feb 2019 13:46:49 -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 DB73B20811; Wed, 13 Feb 2019 18:46:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1550083608; bh=YaLgMlk5ulSiJtjiRMII83+nVG+KDv2bpWqVRxluOBM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Se0ny6J3tkNO37W1eg+7pSZ1rYc60YhADwu81+Xv0k3vGdOmZLPa0wc/fUO+NOLSq /uxWwbyfrxsnpu/d2Y9c4cREvkKB6ioFjvgp4IZF2DjR+9QaIPe52EnE/UoDuF9ygJ 3y432GKrV3V33JKCbieQqtybpx0VZZCqvnJIkxP8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, 3ntr0py1337@gmail.com, Daniel Borkmann , Florian Westphal , Steffen Klassert Subject: [PATCH 4.20 48/50] xfrm: refine validation of template and selector families Date: Wed, 13 Feb 2019 19:38:53 +0100 Message-Id: <20190213183659.456889702@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190213183655.747168774@linuxfoundation.org> References: <20190213183655.747168774@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 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Florian Westphal commit 35e6103861a3a970de6c84688c6e7a1f65b164ca upstream. The check assumes that in transport mode, the first templates family must match the address family of the policy selector. Syzkaller managed to build a template using MODE_ROUTEOPTIMIZATION, with ipv4-in-ipv6 chain, leading to following splat: BUG: KASAN: stack-out-of-bounds in xfrm_state_find+0x1db/0x1854 Read of size 4 at addr ffff888063e57aa0 by task a.out/2050 xfrm_state_find+0x1db/0x1854 xfrm_tmpl_resolve+0x100/0x1d0 xfrm_resolve_and_create_bundle+0x108/0x1000 [..] Problem is that addresses point into flowi4 struct, but xfrm_state_find treats them as being ipv6 because it uses templ->encap_family is used (AF_INET6 in case of reproducer) rather than family (AF_INET). This patch inverts the logic: Enforce 'template family must match selector' EXCEPT for tunnel and BEET mode. In BEET and Tunnel mode, xfrm_tmpl_resolve_one will have remote/local address pointers changed to point at the addresses found in the template, rather than the flowi ones, so no oob read will occur. Reported-by: 3ntr0py1337@gmail.com Reported-by: Daniel Borkmann Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_user.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1488,10 +1488,15 @@ static int validate_tmpl(int nr, struct if (!ut[i].family) ut[i].family = family; - if ((ut[i].mode == XFRM_MODE_TRANSPORT) && - (ut[i].family != prev_family)) - return -EINVAL; - + switch (ut[i].mode) { + case XFRM_MODE_TUNNEL: + case XFRM_MODE_BEET: + break; + default: + if (ut[i].family != prev_family) + return -EINVAL; + break; + } if (ut[i].mode >= XFRM_MODE_MAX) return -EINVAL;