Hi Gao, On Mon, Jan 07, 2013 at 09:27:37AM +0800, Gao feng wrote: > Hi Pablo, > > On 01/05/13 11:50, Pablo Neira Ayuso wrote: > > Hi Gao, > > > > On Fri, Dec 28, 2012 at 10:36:46AM +0800, Gao feng wrote: > >> Currectly we unregister proto before all conntrack entries of > >> this proto being destroyed. so in function destroy_conntrack > >> we can't find proper l4proto to call l4proto->destroy. > >> this will cause resource leak. > > > > Good catch. > > > > But better to remove the entries before unregistering the protocol > > tracker, so l4proto->destroy is always called. > > > > I think the reason we unregister proto before remove all entries > is to avoid new entry for this protocol being created. > > If we remove all contrack entries before unregistration, there maybe > some new entries being created between nf_ct_iterate_cleanup and > nf_conntrack_l4proto_unregister_net.this will cause some terrible things. Leaks are less likely to happen, but may well still happen while racing with protocol removal, agreed. > SO I think we should make proto unavailable first,remove all entries next, > and remove proto from nf_ct_protos arrays finally. Your proposal adds a branch in the packet path to fix an issue that is specific of the GRE protocol tracker. In the current code, this fixes the memory leak while removing the nf_conntrack_proto_gre module, which is a rare operation. We have to come with a less intrusive solution. Regards. -- 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
