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=-19.1 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, 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 A810BC43462 for ; Mon, 17 May 2021 14:27:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8B31B61350 for ; Mon, 17 May 2021 14:27:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239233AbhEQO2V (ORCPT ); Mon, 17 May 2021 10:28:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:53200 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239455AbhEQOYL (ORCPT ); Mon, 17 May 2021 10:24:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3B0E861476; Mon, 17 May 2021 14:12:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621260758; bh=ZFAuTJO59UT5twKnCexyk2VzbleOLvEsm/3HKj7R0A8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lOtDTDtygo35ITjIwS20JHU1ZJ6PlCSx/BJV2gjiIEQbB7hGKqmRu9Z2VcnMbqptM bjm8dcDC1w7W6K77cL/ZjpitKD3gGRzM54rit2Sct68lQ6Li+s7rBuryw+iiH5QkKs N57G+xzzFTZkm5kGHyhqKyp8rYEJDf9kKkKIJqVs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 5.12 228/363] netfilter: nfnetlink_osf: Fix a missing skb_header_pointer() NULL check Date: Mon, 17 May 2021 16:01:34 +0200 Message-Id: <20210517140310.294199173@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140302.508966430@linuxfoundation.org> References: <20210517140302.508966430@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pablo Neira Ayuso [ Upstream commit 5e024c325406470d1165a09c6feaf8ec897936be ] Do not assume that the tcph->doff field is correct when parsing for TCP options, skb_header_pointer() might fail to fetch these bits. Fixes: 11eeef41d5f6 ("netfilter: passive OS fingerprint xtables match") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nfnetlink_osf.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nfnetlink_osf.c b/net/netfilter/nfnetlink_osf.c index 916a3c7f9eaf..79fbf37291f3 100644 --- a/net/netfilter/nfnetlink_osf.c +++ b/net/netfilter/nfnetlink_osf.c @@ -186,6 +186,8 @@ static const struct tcphdr *nf_osf_hdr_ctx_init(struct nf_osf_hdr_ctx *ctx, ctx->optp = skb_header_pointer(skb, ip_hdrlen(skb) + sizeof(struct tcphdr), ctx->optsize, opts); + if (!ctx->optp) + return NULL; } return tcp; -- 2.30.2