netfilter: handle NF_REPEAT from nf_conntrack_in()

NF_REPEAT is only needed from nf_conntrack_in() under a very specific
case required by the TCP protocol tracker, we can handle this case
without returning to the core hook path. Handling of NF_REPEAT from the
nf_reinject() is left untouched.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Pablo Neira Ayuso 2016-11-03 10:56:43 +01:00
parent 26dfab7216
commit 08733a0cb7
3 changed files with 8 additions and 13 deletions

View File

@ -322,8 +322,6 @@ int nf_hook_slow(struct sk_buff *skb, struct nf_hook_state *state,
if (ret == 0) if (ret == 0)
ret = -EPERM; ret = -EPERM;
return ret; return ret;
case NF_REPEAT:
continue;
case NF_QUEUE: case NF_QUEUE:
ret = nf_queue(skb, state, &entry, verdict); ret = nf_queue(skb, state, &entry, verdict);
if (ret == 1 && entry) if (ret == 1 && entry)

View File

@ -1305,7 +1305,7 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
if (skb->nfct) if (skb->nfct)
goto out; goto out;
} }
repeat:
ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum, ct = resolve_normal_ct(net, tmpl, skb, dataoff, pf, protonum,
l3proto, l4proto, &set_reply, &ctinfo); l3proto, l4proto, &set_reply, &ctinfo);
if (!ct) { if (!ct) {
@ -1345,11 +1345,12 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum,
nf_conntrack_event_cache(IPCT_REPLY, ct); nf_conntrack_event_cache(IPCT_REPLY, ct);
out: out:
if (tmpl) { if (tmpl) {
/* Special case: we have to repeat this hook, assign the /* Special case: TCP tracker reports an attempt to reopen a
* template again to this packet. We assume that this packet * closed/aborted connection. We have to go back and create a
* has no conntrack assigned. This is used by nf_ct_tcp. */ * fresh conntrack.
*/
if (ret == NF_REPEAT) if (ret == NF_REPEAT)
skb->nfct = (struct nf_conntrack *)tmpl; goto repeat;
else else
nf_ct_put(tmpl); nf_ct_put(tmpl);
} }

View File

@ -725,12 +725,8 @@ static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
skb->nfctinfo = IP_CT_NEW; skb->nfctinfo = IP_CT_NEW;
} }
/* Repeat if requested, see nf_iterate(). */
do {
err = nf_conntrack_in(net, info->family, err = nf_conntrack_in(net, info->family,
NF_INET_PRE_ROUTING, skb); NF_INET_PRE_ROUTING, skb);
} while (err == NF_REPEAT);
if (err != NF_ACCEPT) if (err != NF_ACCEPT)
return -ENOENT; return -ENOENT;