Patrick McHardy <kaber@xxxxxxxxx> wrote: > On 30.08.2011 12:57, Florian Westphal wrote: > > When incoking iptables hooks from bridge netfilter, the assumption > > that non-confirmed skb->nfct is never shared does no longer hold, > > as bridge code clones skbs when e.g. forwarding packets to multiple > > bridge ports. > > > > When NFQUEUE is used, we can BUG because nf_nat_setup_info can be > > invoked simultaneously for the same conntrack: > > I'm wondering how this can happen, when flooding packets to multiple > ports, they are still processed by the same CPU one after another, > so for the second and further packets, nf_nat should notice that > the mappings are already set up. Main problem is that we end up with same ->nfct in both INPUT and POSTROUTING (br_pass_frame_up vs. br_forward). its extremely unlikely but reproduceable with something like hping2 -i u1200 -2 -p 138 -d 128 192.168.0.255 (assuming bridge interface has an address within that network). Also, with recent change nf_reinject can be run in parallel. (the original problem was observed on 2.6.32.24, but i can reproduce it with nf-next, too). -- 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
