netfilter: conntrack: don't call iter for non-confirmed conntracks
nf_ct_iterate_cleanup_net currently calls iter() callback also for conntracks on the unconfirmed list, but this is unsafe. Acesses to nf_conn are fine, but some users access the extension area in the iter() callback, but that does only work reliably for confirmed conntracks (ct->ext can be reallocated at any time for unconfirmed conntrack). The seond issue is that there is a short window where a conntrack entry is neither on the list nor in the table: To confirm an entry, it is first removed from the unconfirmed list, then insert into the table. Fix this by iterating the unconfirmed list first and marking all entries as dying, then wait for rcu grace period. This makes sure all entries that were about to be confirmed either are in the main table, or will be dropped soon. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Showing
想要评论请 注册 或 登录