From patchwork Wed Dec 13 18:45:14 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 848143 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3yxlxx0k2bz9s7f for ; Thu, 14 Dec 2017 05:45:41 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753799AbdLMSpj (ORCPT ); Wed, 13 Dec 2017 13:45:39 -0500 Received: from mail.us.es ([193.147.175.20]:42554 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753710AbdLMSpg (ORCPT ); Wed, 13 Dec 2017 13:45:36 -0500 Received: from antivirus1-rhel7.int (unknown [192.168.2.11]) by mail.us.es (Postfix) with ESMTP id 375CA174D09 for ; Wed, 13 Dec 2017 19:45:34 +0100 (CET) Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id 271788E791 for ; Wed, 13 Dec 2017 19:45:34 +0100 (CET) Received: by antivirus1-rhel7.int (Postfix, from userid 99) id 1CE8853CDD; Wed, 13 Dec 2017 19:45:34 +0100 (CET) X-Spam-Checker-Version: SpamAssassin 3.4.1 (2015-04-28) on antivirus1-rhel7.int X-Spam-Level: X-Spam-Status: No, score=-108.2 required=7.5 tests=ALL_TRUSTED,BAYES_50, SMTPAUTH_US2,USER_IN_WHITELIST autolearn=disabled version=3.4.1 Received: from antivirus1-rhel7.int (localhost [127.0.0.1]) by antivirus1-rhel7.int (Postfix) with ESMTP id E38EA82954; Wed, 13 Dec 2017 19:45:30 +0100 (CET) Received: from 192.168.1.97 (192.168.1.97) by antivirus1-rhel7.int (F-Secure/fsigk_smtp/550/antivirus1-rhel7.int); Wed, 13 Dec 2017 19:45:30 +0100 (CET) X-Virus-Status: clean(F-Secure/fsigk_smtp/550/antivirus1-rhel7.int) Received: from salvia.here (129.166.216.87.static.jazztel.es [87.216.166.129]) (Authenticated sender: pneira@us.es) by entrada.int (Postfix) with ESMTPA id 930BA4265A31; Wed, 13 Dec 2017 19:45:30 +0100 (CET) X-SMTPAUTHUS: auth mail.us.es From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 06/12] netfilter: conntrack: clamp timeouts to INT_MAX Date: Wed, 13 Dec 2017 19:45:14 +0100 Message-Id: <20171213184520.8193-7-pablo@netfilter.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20171213184520.8193-1-pablo@netfilter.org> References: <20171213184520.8193-1-pablo@netfilter.org> X-Virus-Scanned: ClamAV using ClamSMTP Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jay Elliott When the conntracking code multiplies a timeout by HZ, it can overflow from positive to negative; this causes it to instantly expire. To protect against this the multiplication is done in 64-bit so we can prevent it from exceeding INT_MAX. Signed-off-by: Jay Elliott Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 59c08997bfdf..66d72a8fa87f 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1566,9 +1566,11 @@ static int ctnetlink_change_helper(struct nf_conn *ct, static int ctnetlink_change_timeout(struct nf_conn *ct, const struct nlattr * const cda[]) { - u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT])); + u64 timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ; - ct->timeout = nfct_time_stamp + timeout * HZ; + if (timeout > INT_MAX) + timeout = INT_MAX; + ct->timeout = nfct_time_stamp + (u32)timeout; if (test_bit(IPS_DYING_BIT, &ct->status)) return -ETIME; @@ -1768,6 +1770,7 @@ ctnetlink_create_conntrack(struct net *net, int err = -EINVAL; struct nf_conntrack_helper *helper; struct nf_conn_tstamp *tstamp; + u64 timeout; ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC); if (IS_ERR(ct)) @@ -1776,7 +1779,10 @@ ctnetlink_create_conntrack(struct net *net, if (!cda[CTA_TIMEOUT]) goto err1; - ct->timeout = nfct_time_stamp + ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ; + timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ; + if (timeout > INT_MAX) + timeout = INT_MAX; + ct->timeout = (u32)timeout + nfct_time_stamp; rcu_read_lock(); if (cda[CTA_HELP]) {