Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756554AbdLVK7L (ORCPT ); Fri, 22 Dec 2017 05:59:11 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:60430 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756278AbdLVIsO (ORCPT ); Fri, 22 Dec 2017 03:48:14 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gao Feng , Pablo Neira Ayuso , Sasha Levin Subject: [PATCH 3.18 22/38] netfilter: nf_nat_snmp: Fix panic when snmp_trap_helper fails to register Date: Fri, 22 Dec 2017 09:46:35 +0100 Message-Id: <20171222084453.079660210@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171222084451.623495387@linuxfoundation.org> References: <20171222084451.623495387@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1999 Lines: 65 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gao Feng [ Upstream commit 75c689dca98851d65ef5a27e5ce26b625b68751c ] In the commit 93557f53e1fb ("netfilter: nf_conntrack: nf_conntrack snmp helper"), the snmp_helper is replaced by nf_nat_snmp_hook. So the snmp_helper is never registered. But it still tries to unregister the snmp_helper, it could cause the panic. Now remove the useless snmp_helper and the unregister call in the error handler. Fixes: 93557f53e1fb ("netfilter: nf_conntrack: nf_conntrack snmp helper") Signed-off-by: Gao Feng Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/ipv4/netfilter/nf_nat_snmp_basic.c | 19 +------------------ 1 file changed, 1 insertion(+), 18 deletions(-) --- a/net/ipv4/netfilter/nf_nat_snmp_basic.c +++ b/net/ipv4/netfilter/nf_nat_snmp_basic.c @@ -1260,16 +1260,6 @@ static const struct nf_conntrack_expect_ .timeout = 180, }; -static struct nf_conntrack_helper snmp_helper __read_mostly = { - .me = THIS_MODULE, - .help = help, - .expect_policy = &snmp_exp_policy, - .name = "snmp", - .tuple.src.l3num = AF_INET, - .tuple.src.u.udp.port = cpu_to_be16(SNMP_PORT), - .tuple.dst.protonum = IPPROTO_UDP, -}; - static struct nf_conntrack_helper snmp_trap_helper __read_mostly = { .me = THIS_MODULE, .help = help, @@ -1288,17 +1278,10 @@ static struct nf_conntrack_helper snmp_t static int __init nf_nat_snmp_basic_init(void) { - int ret = 0; - BUG_ON(nf_nat_snmp_hook != NULL); RCU_INIT_POINTER(nf_nat_snmp_hook, help); - ret = nf_conntrack_helper_register(&snmp_trap_helper); - if (ret < 0) { - nf_conntrack_helper_unregister(&snmp_helper); - return ret; - } - return ret; + return nf_conntrack_helper_register(&snmp_trap_helper); } static void __exit nf_nat_snmp_basic_fini(void)