netfilter: flowtable: restrict flow dissector match on meta ingress device

Set on FLOW_DISSECTOR_KEY_META meta key using flow tuple ingress interface.

Fixes: c29f74e0 ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_flow_table_offload.c

@@ -24,6 +24,7 @@ struct flow_offload_work {
 };
 
 struct nf_flow_key {
+	struct flow_dissector_key_meta			meta;
 	struct flow_dissector_key_control		control;
 	struct flow_dissector_key_basic			basic;
 	union {
@@ -55,6 +56,7 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
 	struct nf_flow_key *mask = &match->mask;
 	struct nf_flow_key *key = &match->key;
 
+	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_META, meta);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_CONTROL, control);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_BASIC, basic);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4);
@@ -62,6 +64,9 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_TCP, tcp);
 	NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_PORTS, tp);
 
+	key->meta.ingress_ifindex = tuple->iifidx;
+	mask->meta.ingress_ifindex = 0xffffffff;
+
 	switch (tuple->l3proto) {
 	case AF_INET:
 		key->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
@@ -105,7 +110,8 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
 	key->tp.dst = tuple->dst_port;
 	mask->tp.dst = 0xffff;
 
-	match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_CONTROL) |
+	match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_META) |
+				      BIT(FLOW_DISSECTOR_KEY_CONTROL) |
 				      BIT(FLOW_DISSECTOR_KEY_BASIC) |
 				      BIT(FLOW_DISSECTOR_KEY_PORTS);
 	return 0;