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=-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, 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 008C0C433E9 for ; Mon, 22 Feb 2021 13:48:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BC22764E77 for ; Mon, 22 Feb 2021 13:48:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232107AbhBVNsX (ORCPT ); Mon, 22 Feb 2021 08:48:23 -0500 Received: from mail.kernel.org ([198.145.29.99]:57106 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230261AbhBVMpD (ORCPT ); Mon, 22 Feb 2021 07:45:03 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B809964F0C; Mon, 22 Feb 2021 12:41:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1613997683; bh=velj0HIDEt02HMa8+EIagFSyVCtzhHNflMx6YPpcXZc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RNYSjAg3E3HqezplRpZGKPIvlj5HjTDH2rfFfT5PspoVJnC17+FKBVdcYxp012jGD HCpEoUfd+HTvthzBlyK7EC1ra6Cc9JI0CNmieAsymmvtkFhr//uQmTSVbV0U0JTfHJ a5LMZFY2pdlfbawszj99CdqJ1obxAmXAfZbZA75Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Reindl Harald , Jozsef Kadlecsik , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 4.9 25/49] netfilter: xt_recent: Fix attempt to update deleted entry Date: Mon, 22 Feb 2021 13:36:23 +0100 Message-Id: <20210222121026.807920454@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210222121022.546148341@linuxfoundation.org> References: <20210222121022.546148341@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: Jozsef Kadlecsik [ Upstream commit b1bdde33b72366da20d10770ab7a49fe87b5e190 ] When both --reap and --update flag are specified, there's a code path at which the entry to be updated is reaped beforehand, which then leads to kernel crash. Reap only entries which won't be updated. Fixes kernel bugzilla #207773. Link: https://bugzilla.kernel.org/show_bug.cgi?id=207773 Reported-by: Reindl Harald Fixes: 0079c5aee348 ("netfilter: xt_recent: add an entry reaper") Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin --- net/netfilter/xt_recent.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index 79d7ad621a80f..03c8bd854e56a 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -155,7 +155,8 @@ static void recent_entry_remove(struct recent_table *t, struct recent_entry *e) /* * Drop entries with timestamps older then 'time'. */ -static void recent_entry_reap(struct recent_table *t, unsigned long time) +static void recent_entry_reap(struct recent_table *t, unsigned long time, + struct recent_entry *working, bool update) { struct recent_entry *e; @@ -164,6 +165,12 @@ static void recent_entry_reap(struct recent_table *t, unsigned long time) */ e = list_entry(t->lru_list.next, struct recent_entry, lru_list); + /* + * Do not reap the entry which are going to be updated. + */ + if (e == working && update) + return; + /* * The last time stamp is the most recent. */ @@ -306,7 +313,8 @@ recent_mt(const struct sk_buff *skb, struct xt_action_param *par) /* info->seconds must be non-zero */ if (info->check_set & XT_RECENT_REAP) - recent_entry_reap(t, time); + recent_entry_reap(t, time, e, + info->check_set & XT_RECENT_UPDATE && ret); } if (info->check_set & XT_RECENT_SET || -- 2.27.0