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=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, 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 B2AE7C433EA for ; Tue, 14 Jul 2020 19:07:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8709921D79 for ; Tue, 14 Jul 2020 19:07:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594753662; bh=kTY2Fjn4gqXaQmk4478iYSdk+A5ULQRdbyTB/5xmTzo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QQnijozZifUQFZuGDqv9zLmBMjMJiLq6H/kZ5AcoLwU1Qu6e8q2P15FIvrZfyIcJs 5lM3bGtsrVMnJpT8N1MhCaFgwLf76G+UCi3Wmp1AJXgkpyw2NfoZ3T2TgYngpfqAg6 A67rZjvhV3Ac3zxLzFO5zE4QVVJtf7i6tH1EREY0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730414AbgGNSvo (ORCPT ); Tue, 14 Jul 2020 14:51:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:48238 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729986AbgGNSvn (ORCPT ); Tue, 14 Jul 2020 14:51:43 -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 0201122B2A; Tue, 14 Jul 2020 18:51:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1594752702; bh=kTY2Fjn4gqXaQmk4478iYSdk+A5ULQRdbyTB/5xmTzo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=o9sxlssVWti3vjFqBFIMLCfV/JepOOFUZ4wH7EIjXfw5EyetujGrH/2hMh5fwKIIT aFnZICgy5bbvJB4al7ckHPT/cwFAaR1mG3LDpg8oO0r7Cpyxva5yVe/0Ox+LibVoDS 5OZlLOb3S3sSXiBn0YmPDNKHrbTyMSoRCTlukTok= 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 5.4 047/109] netfilter: conntrack: refetch conntrack after nf_conntrack_update() Date: Tue, 14 Jul 2020 20:43:50 +0200 Message-Id: <20200714184107.774838090@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200714184105.507384017@linuxfoundation.org> References: <20200714184105.507384017@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: Pablo Neira Ayuso [ Upstream commit d005fbb855d3b5660d62ee5a6bd2d99c13ff8cf3 ] __nf_conntrack_update() might refresh the conntrack object that is attached to the skbuff. Otherwise, this triggers UAF. [ 633.200434] ================================================================== [ 633.200472] BUG: KASAN: use-after-free in nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200478] Read of size 1 at addr ffff888370804c00 by task nfqnl_test/6769 [ 633.200487] CPU: 1 PID: 6769 Comm: nfqnl_test Not tainted 5.8.0-rc2+ #388 [ 633.200490] Hardware name: LENOVO 23259H1/23259H1, BIOS G2ET32WW (1.12 ) 05/30/2012 [ 633.200491] Call Trace: [ 633.200499] dump_stack+0x7c/0xb0 [ 633.200526] ? nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200532] print_address_description.constprop.6+0x1a/0x200 [ 633.200539] ? _raw_write_lock_irqsave+0xc0/0xc0 [ 633.200568] ? nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200594] ? nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200598] kasan_report.cold.9+0x1f/0x42 [ 633.200604] ? call_rcu+0x2c0/0x390 [ 633.200633] ? nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200659] nf_conntrack_update+0x34e/0x770 [nf_conntrack] [ 633.200687] ? nf_conntrack_find_get+0x30/0x30 [nf_conntrack] Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1436 Fixes: ee04805ff54a ("netfilter: conntrack: make conntrack userspace helpers work again") Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/nf_conntrack_core.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 48db4aec02dea..200cdad3ff3ab 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -2012,6 +2012,8 @@ static int nf_conntrack_update(struct net *net, struct sk_buff *skb) err = __nf_conntrack_update(net, skb, ct, ctinfo); if (err < 0) return err; + + ct = nf_ct_get(skb, &ctinfo); } return nf_confirm_cthelper(skb, ct, ctinfo); -- 2.25.1