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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 E5A38C33CB1 for ; Sat, 18 Jan 2020 11:21:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AAE9A24690 for ; Sat, 18 Jan 2020 11:21:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=riseup.net header.i=@riseup.net header.b="qoBE0IZR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727079AbgARLVh (ORCPT ); Sat, 18 Jan 2020 06:21:37 -0500 Received: from mx1.riseup.net ([198.252.153.129]:44076 "EHLO mx1.riseup.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727068AbgARLVh (ORCPT ); Sat, 18 Jan 2020 06:21:37 -0500 Received: from capuchin.riseup.net (capuchin-pn.riseup.net [10.0.1.176]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (Client CN "*.riseup.net", Issuer "Sectigo RSA Domain Validation Secure Server CA" (not verified)) by mx1.riseup.net (Postfix) with ESMTPS id 480Fqf14pfzFdXZ; Sat, 18 Jan 2020 03:21:18 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=riseup.net; s=squak; t=1579346496; bh=QJEPdK/YGcCfMbPE9IMD5dGTX50/fYxJzN9rjYnYwEU=; h=Date:In-Reply-To:References:Subject:To:CC:From:From; b=qoBE0IZRM4WsV3VmjjYojC+CmZamMuh+jheTBC1QSuAnJrHKxLw1WJ4htryS2i9Wc 1GpnzdoMBsFm6eukIS+UHzVkYYzbOYEkzFxE5JUcYNsYxK50gtNCsNSzIIN3AIQWBC mhTIUPFltfmDTzmRdpVvsm+imryBw//8JVWZY52s= X-Riseup-User-ID: 5049827D8377340B9CA21926B3C15D3EEBCDE3A21467627784C82250557A7ED0 Received: from [127.0.0.1] (localhost [127.0.0.1]) by capuchin.riseup.net (Postfix) with ESMTPSA id 480Fqd1VR3z8w8Q; Sat, 18 Jan 2020 03:21:17 -0800 (PST) Date: Sat, 18 Jan 2020 12:21:06 +0100 In-Reply-To: <20200118102725.30600-1-fw@strlen.de> References: <000000000000d740e5059c65cbd0@google.com> <20200118102725.30600-1-fw@strlen.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH nf] netfilter: nft_osf: add missing check for DREG attribute To: Florian Westphal , netfilter-devel@vger.kernel.org CC: syzkaller-bugs@googlegroups.com, syzbot+cf23983d697c26c34f60@syzkaller.appspotmail.com From: =?ISO-8859-1?Q?Fernando_Fern=E1ndez_Mancera?= Message-ID: <284AF1FF-D477-4CD2-B5BE-15FD40B103E1@riseup.net> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org El 18 de enero de 2020 11:27:25 CET, Florian Westphal escr= ibi=C3=B3: >syzbot reports just another NULL deref crash because of missing test >for presence of the attribute=2E > >Reported-by: syzbot+cf23983d697c26c34f60@syzkaller=2Eappspotmail=2Ecom >Fixes: b96af92d6eaf9fadd ("netfilter: nf_tables: implement Passive OS >fingerprint module in nft_osf") >Signed-off-by: Florian Westphal >--- > net/netfilter/nft_osf=2Ec | 3 +++ > 1 file changed, 3 insertions(+) > >diff --git a/net/netfilter/nft_osf=2Ec b/net/netfilter/nft_osf=2Ec >index f54d6ae15bb1=2E=2Eb42247aa48a9 100644 >--- a/net/netfilter/nft_osf=2Ec >+++ b/net/netfilter/nft_osf=2Ec >@@ -61,6 +61,9 @@ static int nft_osf_init(const struct nft_ctx *ctx, > int err; > u8 ttl; >=20 >+ if (!tb[NFTA_OSF_DREG]) >+ return -EINVAL; >+ > if (tb[NFTA_OSF_TTL]) { > ttl =3D nla_get_u8(tb[NFTA_OSF_TTL]); > if (ttl > 2) Oops=2E Sorry about that=2E Thanks Florian!