On Mon, 2014-02-03 at 23:09 +0100, Pablo Neira Ayuso wrote: > With this patch, the conntrack refcount is initially set to zero and > it is bumped once it is added to any of the list, so we fulfill > Eric's golden rule which is that all released objects always have a > refcount that equals zero. > > Andrey Vagin reports that nf_conntrack_free can't be called for a > conntrack with non-zero ref-counter, because it can race with > nf_conntrack_find_get(). > > A conntrack slab is created with SLAB_DESTROY_BY_RCU. Non-zero > ref-counter says that this conntrack is used. So when we release > a conntrack with non-zero counter, we break this assumption. ... > Cc: Eric Dumazet <eric.dumazet@xxxxxxxxx> > Cc: Florian Westphal <fw@xxxxxxxxx> > Cc: Andrew Vagin <avagin@xxxxxxxxxxxxx> > Reported-by: Andrew Vagin <avagin@xxxxxxxxxxxxx> > Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> > --- SGTM ! Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx> -- 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
