From patchwork Wed Feb 8 11:43:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steffen Klassert X-Patchwork-Id: 13133004 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 52B8AC636D6 for ; Wed, 8 Feb 2023 11:43:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231258AbjBHLnf (ORCPT ); Wed, 8 Feb 2023 06:43:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230150AbjBHLna (ORCPT ); Wed, 8 Feb 2023 06:43:30 -0500 Received: from a.mx.secunet.com (a.mx.secunet.com [62.96.220.36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 409524615E for ; Wed, 8 Feb 2023 03:43:29 -0800 (PST) Received: from localhost (localhost [127.0.0.1]) by a.mx.secunet.com (Postfix) with ESMTP id E1A3D205CB; Wed, 8 Feb 2023 12:43:27 +0100 (CET) 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 es847qLKjrXS; Wed, 8 Feb 2023 12:43:27 +0100 (CET) Received: from mailout1.secunet.com (mailout1.secunet.com [62.96.220.44]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by a.mx.secunet.com (Postfix) with ESMTPS id 7CE7B2065A; Wed, 8 Feb 2023 12:43:26 +0100 (CET) Received: from cas-essen-01.secunet.de (unknown [10.53.40.201]) by mailout1.secunet.com (Postfix) with ESMTP id 6F25280004A; Wed, 8 Feb 2023 12:43:26 +0100 (CET) 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 15.1.2507.17; Wed, 8 Feb 2023 12:43:26 +0100 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 15.1.2507.17; Wed, 8 Feb 2023 12:43:25 +0100 Received: by gauss2.secunet.de (Postfix, from userid 1000) id 70A953182EAA; Wed, 8 Feb 2023 12:43:25 +0100 (CET) From: Steffen Klassert To: David Miller , Jakub Kicinski CC: Herbert Xu , Steffen Klassert , Subject: [PATCH 3/6] xfrm/compat: prevent potential spectre v1 gadget in xfrm_xlate32_attr() Date: Wed, 8 Feb 2023 12:43:19 +0100 Message-ID: <20230208114322.266510-4-steffen.klassert@secunet.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230208114322.266510-1-steffen.klassert@secunet.com> References: <20230208114322.266510-1-steffen.klassert@secunet.com> MIME-Version: 1.0 X-ClientProxiedBy: cas-essen-01.secunet.de (10.53.40.201) To mbx-essen-01.secunet.de (10.53.40.197) X-EXCLAIMER-MD-CONFIG: 2c86f778-e09b-4440-8b15-867914633a10 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Eric Dumazet int type = nla_type(nla); if (type > XFRMA_MAX) { return -EOPNOTSUPP; } @type is then used as an array index and can be used as a Spectre v1 gadget. if (nla_len(nla) < compat_policy[type].len) { array_index_nospec() can be used to prevent leaking content of kernel memory to malicious users. Fixes: 5106f4a8acff ("xfrm/compat: Add 32=>64-bit messages translator") Signed-off-by: Eric Dumazet Cc: Dmitry Safonov Cc: Steffen Klassert Reviewed-by: Dmitry Safonov Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_compat.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/xfrm/xfrm_compat.c b/net/xfrm/xfrm_compat.c index 12405aa5bce8..8cbf45a8bcdc 100644 --- a/net/xfrm/xfrm_compat.c +++ b/net/xfrm/xfrm_compat.c @@ -5,6 +5,7 @@ * Based on code and translator idea by: Florian Westphal */ #include +#include #include #include @@ -437,6 +438,7 @@ static int xfrm_xlate32_attr(void *dst, const struct nlattr *nla, NL_SET_ERR_MSG(extack, "Bad attribute"); return -EOPNOTSUPP; } + type = array_index_nospec(type, XFRMA_MAX + 1); if (nla_len(nla) < compat_policy[type].len) { NL_SET_ERR_MSG(extack, "Attribute bad length"); return -EOPNOTSUPP;