Hi Pablo, > -----Original Message----- > From: netfilter-devel-owner@xxxxxxxxxxxxxxx > [mailto:netfilter-devel-owner@xxxxxxxxxxxxxxx] On Behalf Of Pablo Neira Ayuso > Sent: Friday, March 24, 2017 8:23 PM > To: fgao@xxxxxxxxxx > Cc: davem@xxxxxxxxxxxxx; jolsa@xxxxxxxxxx; netfilter-devel@xxxxxxxxxxxxxxx; > netdev@xxxxxxxxxxxxxxx; gfree.wind@xxxxxxxxx > Subject: Re: [PATCH nf v3 1/1] netfilter: snmp: Fix one possible panic when > snmp_trap_helper fail to register > > On Fri, Mar 24, 2017 at 01:21:30PM +0100, Pablo Neira Ayuso wrote: > > On Tue, Mar 21, 2017 at 08:22:29AM +0800, fgao@xxxxxxxxxx wrote: > > > From: Gao Feng <fgao@xxxxxxxxxx> > > > > > > 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. > > > > This patch looks correct to me. > > > > But probably for some reason I don't manage to trigger, how do you > > reproduce this? > > I'm refering to the panic. [高峰] It is got by reviewing the codes. When nf_conntrack_helper_unregister(&snmp_helper), but snmp_helper didn't register actually. And snmp_helper. hnode is not initialized, it would trigger the issue when hlist_del_rcu in nf_conntrack_helper_unregister. Best Regards Feng > -- > To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the > body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at > http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
