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=-6.9 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=unavailable 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 0AA4FC2D0F3 for ; Tue, 31 Mar 2020 09:19:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC5EF2072E for ; Tue, 31 Mar 2020 09:19:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585646391; bh=+2Yc5/72cHKArA4R+dzFgQDsJ7e4GYHSq8Ld72MC4zE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YF2UMCHZIdn86NrIf0nI/LAuSfSbK2OY7QeCYIk2eKGrDcR7vLRD/dIZWcyHnHGyk 8k43+XnPYW1id0sstSrpkiRWiOgqfp9uhMSBiR49c2WU3AKJKaDiMjGXcdPJpzQhol GY/n3SrkJXIdIFfN316IQFYO96xciwQkNpStcMQA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731534AbgCaJQt (ORCPT ); Tue, 31 Mar 2020 05:16:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:37634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731535AbgCaJQq (ORCPT ); Tue, 31 Mar 2020 05:16:46 -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 63499208E0; Tue, 31 Mar 2020 09:16:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1585646205; bh=+2Yc5/72cHKArA4R+dzFgQDsJ7e4GYHSq8Ld72MC4zE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sZfDjhq0ou7HT/dys4JzQib4oCBqVINZg2Eiwg8shCF2yWZj7YpctxigC1+5RJczr wTchjwL8nVFCbVwnaGRA/mhVVOMK1FsFEBN9xwEFeEuext5zcbC4/fjvkUOkDwDPeb OTJ3Vccbp0rMnbHCnnSp6it49T3N4uBrBS15BQU0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Xin Long , Steffen Klassert Subject: [PATCH 5.4 116/155] xfrm: fix uctx len check in verify_sec_ctx_len Date: Tue, 31 Mar 2020 10:59:16 +0200 Message-Id: <20200331085431.490001424@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200331085418.274292403@linuxfoundation.org> References: <20200331085418.274292403@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Xin Long commit 171d449a028573b2f0acdc7f31ecbb045391b320 upstream. It's not sufficient to do 'uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len)' check only, as uctx->len may be greater than nla_len(rt), in which case it will cause slab-out-of-bounds when accessing uctx->ctx_str later. This patch is to fix it by return -EINVAL when uctx->len > nla_len(rt). Fixes: df71837d5024 ("[LSM-IPSec]: Security association restriction.") Signed-off-by: Xin Long Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman --- net/xfrm/xfrm_user.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -110,7 +110,8 @@ static inline int verify_sec_ctx_len(str return 0; uctx = nla_data(rt); - if (uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len)) + if (uctx->len > nla_len(rt) || + uctx->len != (sizeof(struct xfrm_user_sec_ctx) + uctx->ctx_len)) return -EINVAL; return 0;