ipvs: attempt to schedule icmp packets

Invoke the try_to_schedule logic from the icmp path and update it to the
appropriate ip_vs_conn_put function.  The schedule functions have been
updated to reject the packets immediately for now.
Signed-off-by: Alex Gartrell <agartrell@fb.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>

net/netfilter/ipvs/ip_vs_core.c

@@ -1409,7 +1409,7 @@ ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
 	struct ip_vs_protocol *pp;
 	struct ip_vs_proto_data *pd;
 	unsigned int offset, offset2, ihl, verdict;
-	bool ipip;
+	bool ipip, new_cp = false;
 
 	*related = 1;
 
@@ -1487,8 +1487,17 @@ ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
 	 * For IPIP this is error for request, not for reply.
 	 */
 	cp = pp->conn_in_get(AF_INET, skb, &ciph);
-	if (!cp)
-		return NF_ACCEPT;
+
+	if (!cp) {
+		int v;
+
+		if (!sysctl_schedule_icmp(net_ipvs(net)))
+			return NF_ACCEPT;
+
+		if (!ip_vs_try_to_schedule(AF_INET, skb, pd, &v, &cp, &ciph))
+			return v;
+		new_cp = true;
+	}
 
 	verdict = NF_DROP;
 
@@ -1565,7 +1574,10 @@ ip_vs_in_icmp(struct sk_buff *skb, int *related, unsigned int hooknum)
 	verdict = ip_vs_icmp_xmit(skb, cp, pp, offset, hooknum, &ciph);
 
 out:
-	__ip_vs_conn_put(cp);
+	if (likely(!new_cp))
+		__ip_vs_conn_put(cp);
+	else
+		ip_vs_conn_put(cp);
 
 	return verdict;
 }
@@ -1581,6 +1593,7 @@ static int ip_vs_in_icmp_v6(struct sk_buff *skb, int *related,
 	struct ip_vs_protocol *pp;
 	struct ip_vs_proto_data *pd;
 	unsigned int offset, verdict;
+	bool new_cp = false;
 
 	*related = 1;
 
@@ -1631,13 +1644,23 @@ static int ip_vs_in_icmp_v6(struct sk_buff *skb, int *related,
 	 */
 	cp = pp->conn_in_get(AF_INET6, skb, &ciph);
 
-	if (!cp)
-		return NF_ACCEPT;
+	if (!cp) {
+		int v;
+
+		if (!sysctl_schedule_icmp(net_ipvs(net)))
+			return NF_ACCEPT;
+
+		if (!ip_vs_try_to_schedule(AF_INET6, skb, pd, &v, &cp, &ciph))
+			return v;
+
+		new_cp = true;
+	}
+
 	/* VS/TUN, VS/DR and LOCALNODE just let it go */
 	if ((hooknum == NF_INET_LOCAL_OUT) &&
 	    (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ)) {
-		__ip_vs_conn_put(cp);
-		return NF_ACCEPT;
+		verdict = NF_ACCEPT;
+		goto out;
 	}
 
 	/* do the statistics and put it back */
@@ -1651,7 +1674,11 @@ static int ip_vs_in_icmp_v6(struct sk_buff *skb, int *related,
 
 	verdict = ip_vs_icmp_xmit_v6(skb, cp, pp, offset, hooknum, &ciph);
 
-	__ip_vs_conn_put(cp);
+out:
+	if (likely(!new_cp))
+		__ip_vs_conn_put(cp);
+	else
+		ip_vs_conn_put(cp);
 
 	return verdict;
 }

net/netfilter/ipvs/ip_vs_proto_sctp.c

@@ -19,6 +19,12 @@ sctp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 	sctp_chunkhdr_t _schunkh, *sch;
 	sctp_sctphdr_t *sh, _sctph;
 
+	if (ip_vs_iph_icmp(iph)) {
+		/* TEMPORARY - do not schedule icmp yet */
+		*verdict = NF_ACCEPT;
+		return 0;
+	}
+
 	sh = skb_header_pointer(skb, iph->len, sizeof(_sctph), &_sctph);
 	if (sh == NULL) {
 		*verdict = NF_DROP;

net/netfilter/ipvs/ip_vs_proto_tcp.c

@@ -41,6 +41,12 @@ tcp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 	struct tcphdr _tcph, *th;
 	struct netns_ipvs *ipvs;
 
+	if (ip_vs_iph_icmp(iph)) {
+		/* TEMPORARY - do not schedule icmp yet */
+		*verdict = NF_ACCEPT;
+		return 0;
+	}
+
 	th = skb_header_pointer(skb, iph->len, sizeof(_tcph), &_tcph);
 	if (th == NULL) {
 		*verdict = NF_DROP;
@@ -48,6 +54,7 @@ tcp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 	}
 	net = skb_net(skb);
 	ipvs = net_ipvs(net);
+
 	/* No !th->ack check to allow scheduling on SYN+ACK for Active FTP */
 	rcu_read_lock();
 	if ((th->syn || sysctl_sloppy_tcp(ipvs)) && !th->rst &&

net/netfilter/ipvs/ip_vs_proto_udp.c

@@ -37,6 +37,12 @@ udp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd,
 	struct ip_vs_service *svc;
 	struct udphdr _udph, *uh;
 
+	if (ip_vs_iph_icmp(iph)) {
+		/* TEMPORARY - do not schedule icmp yet */
+		*verdict = NF_ACCEPT;
+		return 0;
+	}
+
 	/* IPv6 fragments, only first fragment will hit this */
 	uh = skb_header_pointer(skb, iph->len, sizeof(_udph), &_udph);
 	if (uh == NULL) {