Hi,

I've been discussing this with Eric. __ip_conntrack_confirm is entered from
both process context and net_rx_softirq context and "++" operations aren't
atomic.

So net_rx_softirq can preempt the calling process while incrementing the 
stats.
I think that we can fix this moving both CONNTRACK_STAT_INC to the locked
section.

regards,
Pablo

Signed-off-by: Pablo Neira Ayuso <pablo@eurodev.net>