From patchwork Mon Apr 12 08:40:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 420015 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 1964FC433ED for ; Mon, 12 Apr 2021 08:57:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EAC1361279 for ; Mon, 12 Apr 2021 08:57:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238608AbhDLI6G (ORCPT ); Mon, 12 Apr 2021 04:58:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:50004 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238573AbhDLI4a (ORCPT ); Mon, 12 Apr 2021 04:56:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id F321B6124A; Mon, 12 Apr 2021 08:56:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618217772; bh=2sIrRiXC24IZ3c+sMIwarCIiK0yziEiQgeC2Jk0JQKw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UxD//1Z51U1zgQcFCa2j8xTvxqIaLiTExiLfQ3sRzL0cVteqeV4Ducyhr7Rga9xaq SGCgxFIxi9qPF13l1R/MS8dawwVOHplosovVoI6cGzYGp86SYmPEDGrxtQ+WEvqce1 2P4bQEunK+OvwPYa40lNZrWxreNwuys8C/vjrlLk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Steffen Klassert , Sasha Levin Subject: [PATCH 5.10 104/188] xfrm: Fix NULL pointer dereference on policy lookup Date: Mon, 12 Apr 2021 10:40:18 +0200 Message-Id: <20210412084017.108022670@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084013.643370347@linuxfoundation.org> References: <20210412084013.643370347@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Steffen Klassert [ Upstream commit b1e3a5607034aa0a481c6f69a6893049406665fb ] When xfrm interfaces are used in combination with namespaces and ESP offload, we get a dst_entry NULL pointer dereference. This is because we don't have a dst_entry attached in the ESP offloading case and we need to do a policy lookup before the namespace transition. Fix this by expicit checking of skb_dst(skb) before accessing it. Fixes: f203b76d78092 ("xfrm: Add virtual xfrm interfaces") Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- include/net/xfrm.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/net/xfrm.h b/include/net/xfrm.h index bfbc7810df94..c58a6d4eb610 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1097,7 +1097,7 @@ static inline int __xfrm_policy_check2(struct sock *sk, int dir, return __xfrm_policy_check(sk, ndir, skb, family); return (!net->xfrm.policy_count[dir] && !secpath_exists(skb)) || - (skb_dst(skb)->flags & DST_NOPOLICY) || + (skb_dst(skb) && (skb_dst(skb)->flags & DST_NOPOLICY)) || __xfrm_policy_check(sk, ndir, skb, family); }