From mboxrd@z Thu Jan 1 00:00:00 1970 From: gfree.wind@foxmail.com Subject: [PATCH nf v4 1/1] netfilter: snmp: Fix one possible panic when snmp_trap_helper fail to register Date: Sat, 25 Mar 2017 10:24:06 +0800 Message-ID: <1490408646-26051-1-git-send-email-gfree.wind@foxmail.com> Cc: Gao Feng To: pablo@netfilter.org, netfilter-devel@vger.kernel.org, gfree.wind@foxmail.com Return-path: Received: from smtpbgau1.qq.com ([54.206.16.166]:57655 "EHLO smtpbgau1.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934005AbdCYCY0 (ORCPT ); Fri, 24 Mar 2017 22:24:26 -0400 Sender: netfilter-devel-owner@vger.kernel.org List-ID: From: Gao Feng 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 --- v4: Simplify the codes, per Pablo v3: Remove the angle brackets in description, per Sergei v2: Add the SHA1 ID in the description, per Sergei v1: Initial version net/ipv4/netfilter/nf_nat_snmp_basic.c | 17 +---------------- 1 file changed, 1 insertion(+), 16 deletions(-) diff --git a/net/ipv4/netfilter/nf_nat_snmp_basic.c b/net/ipv4/netfilter/nf_nat_snmp_basic.c index c9b52c3..36d16e5 100644 --- a/net/ipv4/netfilter/nf_nat_snmp_basic.c +++ b/net/ipv4/netfilter/nf_nat_snmp_basic.c @@ -1260,16 +1260,6 @@ static int help(struct sk_buff *skb, unsigned int protoff, .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, @@ -1293,12 +1283,7 @@ static int __init nf_nat_snmp_basic_init(void) 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) -- 1.9.1