1 files changed, 71 insertions, 8 deletions

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index d8c2327..cd71190 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -363,7 +363,7 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
 static int igmpv3_sendpack(struct sk_buff *skb)
 {
 	struct igmphdr *pig = igmp_hdr(skb);
-	const int igmplen = skb->tail - skb->transport_header;
+	const int igmplen = skb_tail_pointer(skb) - skb_transport_header(skb);
 
 	pig->csum = ip_compute_csum(igmp_hdr(skb), igmplen);
 
@@ -1217,6 +1217,57 @@ static void igmp_group_added(struct ip_mc_list *im)
  *	Multicast list managers
  */
 
+static u32 ip_mc_hash(const struct ip_mc_list *im)
+{
+	return hash_32((__force u32)im->multiaddr, MC_HASH_SZ_LOG);
+}
+
+static void ip_mc_hash_add(struct in_device *in_dev,
+			   struct ip_mc_list *im)
+{
+	struct ip_mc_list __rcu **mc_hash;
+	u32 hash;
+
+	mc_hash = rtnl_dereference(in_dev->mc_hash);
+	if (mc_hash) {
+		hash = ip_mc_hash(im);
+		im->next_hash = mc_hash[hash];
+		rcu_assign_pointer(mc_hash[hash], im);
+		return;
+	}
+
+	/* do not use a hash table for small number of items */
+	if (in_dev->mc_count < 4)
+		return;
+
+	mc_hash = kzalloc(sizeof(struct ip_mc_list *) << MC_HASH_SZ_LOG,
+			  GFP_KERNEL);
+	if (!mc_hash)
+		return;
+
+	for_each_pmc_rtnl(in_dev, im) {
+		hash = ip_mc_hash(im);
+		im->next_hash = mc_hash[hash];
+		RCU_INIT_POINTER(mc_hash[hash], im);
+	}
+
+	rcu_assign_pointer(in_dev->mc_hash, mc_hash);
+}
+
+static void ip_mc_hash_remove(struct in_device *in_dev,
+			      struct ip_mc_list *im)
+{
+	struct ip_mc_list __rcu **mc_hash = rtnl_dereference(in_dev->mc_hash);
+	struct ip_mc_list *aux;
+
+	if (!mc_hash)
+		return;
+	mc_hash += ip_mc_hash(im);
+	while ((aux = rtnl_dereference(*mc_hash)) != im)
+		mc_hash = &aux->next_hash;
+	*mc_hash = im->next_hash;
+}
+
 
 /*
  *	A socket has joined a multicast group on device dev.
@@ -1258,6 +1309,8 @@ void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
 	in_dev->mc_count++;
 	rcu_assign_pointer(in_dev->mc_list, im);
 
+	ip_mc_hash_add(in_dev, im);
+
 #ifdef CONFIG_IP_MULTICAST
 	igmpv3_del_delrec(in_dev, im->multiaddr);
 #endif
@@ -1314,6 +1367,7 @@ void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
 	     ip = &i->next_rcu) {
 		if (i->multiaddr == addr) {
 			if (--i->users == 0) {
+				ip_mc_hash_remove(in_dev, i);
 				*ip = i->next_rcu;
 				in_dev->mc_count--;
 				igmp_group_dropped(i);
@@ -1381,13 +1435,9 @@ void ip_mc_init_dev(struct in_device *in_dev)
 {
 	ASSERT_RTNL();
 
-	in_dev->mc_tomb = NULL;
 #ifdef CONFIG_IP_MULTICAST
-	in_dev->mr_gq_running = 0;
 	setup_timer(&in_dev->mr_gq_timer, igmp_gq_timer_expire,
 			(unsigned long)in_dev);
-	in_dev->mr_ifc_count = 0;
-	in_dev->mc_count     = 0;
 	setup_timer(&in_dev->mr_ifc_timer, igmp_ifc_timer_expire,
 			(unsigned long)in_dev);
 	in_dev->mr_qrv = IGMP_Unsolicited_Report_Count;
@@ -2321,12 +2371,25 @@ void ip_mc_drop_socket(struct sock *sk)
 int ip_check_mc_rcu(struct in_device *in_dev, __be32 mc_addr, __be32 src_addr, u16 proto)
 {
 	struct ip_mc_list *im;
+	struct ip_mc_list __rcu **mc_hash;
 	struct ip_sf_list *psf;
 	int rv = 0;
 
-	for_each_pmc_rcu(in_dev, im) {
-		if (im->multiaddr == mc_addr)
-			break;
+	mc_hash = rcu_dereference(in_dev->mc_hash);
+	if (mc_hash) {
+		u32 hash = hash_32((__force u32)mc_addr, MC_HASH_SZ_LOG);
+
+		for (im = rcu_dereference(mc_hash[hash]);
+		     im != NULL;
+		     im = rcu_dereference(im->next_hash)) {
+			if (im->multiaddr == mc_addr)
+				break;
+		}
+	} else {
+		for_each_pmc_rcu(in_dev, im) {
+			if (im->multiaddr == mc_addr)
+				break;
+		}
 	}
 	if (im && proto == IPPROTO_IGMP) {
 		rv = 1;