1 files changed, 264 insertions, 110 deletions

diff --git a/drivers/net/amt.c b/drivers/net/amt.c
index f1a36d7e2151..902c817a0dea 100644
--- a/drivers/net/amt.c
+++ b/drivers/net/amt.c
@@ -11,7 +11,8 @@
 #include <linux/net.h>
 #include <linux/igmp.h>
 #include <linux/workqueue.h>
-#include <net/sch_generic.h>
+#include <net/flow.h>
+#include <net/pkt_sched.h>
 #include <net/net_namespace.h>
 #include <net/ip.h>
 #include <net/udp.h>
@@ -28,6 +29,7 @@
 #include <net/addrconf.h>
 #include <net/ip6_route.h>
 #include <net/inet_common.h>
+#include <net/inet_dscp.h>
 #include <net/ip6_checksum.h>
 
 static struct workqueue_struct *amt_wq;
@@ -51,13 +53,14 @@ static char *status_str[] = {
 };
 
 static char *type_str[] = {
+	"", /* Type 0 is not defined */
 	"AMT_MSG_DISCOVERY",
 	"AMT_MSG_ADVERTISEMENT",
 	"AMT_MSG_REQUEST",
 	"AMT_MSG_MEMBERSHIP_QUERY",
 	"AMT_MSG_MEMBERSHIP_UPDATE",
 	"AMT_MSG_MULTICAST_DATA",
-	"AMT_MSG_TEARDOWM",
+	"AMT_MSG_TEARDOWN",
 };
 
 static char *action_str[] = {
@@ -79,11 +82,11 @@ static struct mld2_grec mldv2_zero_grec;
 
 static struct amt_skb_cb *amt_skb_cb(struct sk_buff *skb)
 {
-	BUILD_BUG_ON(sizeof(struct amt_skb_cb) + sizeof(struct qdisc_skb_cb) >
+	BUILD_BUG_ON(sizeof(struct amt_skb_cb) + sizeof(struct tc_skb_cb) >
 		     sizeof_field(struct sk_buff, cb));
 
 	return (struct amt_skb_cb *)((void *)skb->cb +
-		sizeof(struct qdisc_skb_cb));
+		sizeof(struct tc_skb_cb));
 }
 
 static void __amt_source_gc_work(void)
@@ -448,7 +451,7 @@ out:
 	dev_put(amt->dev);
 }
 
-/* Non-existant group is created as INCLUDE {empty}:
+/* Non-existent group is created as INCLUDE {empty}:
  *
  * RFC 3376 - 5.1. Action on Change of Interface State
  *
@@ -562,7 +565,7 @@ static struct sk_buff *amt_build_igmp_gq(struct amt_dev *amt)
 	ihv3->nsrcs	= 0;
 	ihv3->resv	= 0;
 	ihv3->suppress	= false;
-	ihv3->qrv	= amt->net->ipv4.sysctl_igmp_qrv;
+	ihv3->qrv	= READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv);
 	ihv3->csum	= 0;
 	csum		= &ihv3->csum;
 	csum_start	= (void *)ihv3;
@@ -576,14 +579,14 @@ static struct sk_buff *amt_build_igmp_gq(struct amt_dev *amt)
 	return skb;
 }
 
-static void __amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
-				   bool validate)
+static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
+				 bool validate)
 {
 	if (validate && amt->status >= status)
 		return;
 	netdev_dbg(amt->dev, "Update GW status %s -> %s",
 		   status_str[amt->status], status_str[status]);
-	amt->status = status;
+	WRITE_ONCE(amt->status, status);
 }
 
 static void __amt_update_relay_status(struct amt_tunnel_list *tunnel,
@@ -599,14 +602,6 @@ static void __amt_update_relay_status(struct amt_tunnel_list *tunnel,
 	tunnel->status = status;
 }
 
-static void amt_update_gw_status(struct amt_dev *amt, enum amt_status status,
-				 bool validate)
-{
-	spin_lock_bh(&amt->lock);
-	__amt_update_gw_status(amt, status, validate);
-	spin_unlock_bh(&amt->lock);
-}
-
 static void amt_update_relay_status(struct amt_tunnel_list *tunnel,
 				    enum amt_status status, bool validate)
 {
@@ -699,9 +694,7 @@ static void amt_send_discovery(struct amt_dev *amt)
 	if (unlikely(net_xmit_eval(err)))
 		amt->dev->stats.tx_errors++;
 
-	spin_lock_bh(&amt->lock);
-	__amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true);
-	spin_unlock_bh(&amt->lock);
+	amt_update_gw_status(amt, AMT_STATUS_SENT_DISCOVERY, true);
 out:
 	rcu_read_unlock();
 }
@@ -899,6 +892,28 @@ static void amt_send_mld_gq(struct amt_dev *amt, struct amt_tunnel_list *tunnel)
 }
 #endif
 
+static bool amt_queue_event(struct amt_dev *amt, enum amt_event event,
+			    struct sk_buff *skb)
+{
+	int index;
+
+	spin_lock_bh(&amt->lock);
+	if (amt->nr_events >= AMT_MAX_EVENTS) {
+		spin_unlock_bh(&amt->lock);
+		return 1;
+	}
+
+	index = (amt->event_idx + amt->nr_events) % AMT_MAX_EVENTS;
+	amt->events[index].event = event;
+	amt->events[index].skb = skb;
+	amt->nr_events++;
+	amt->event_idx %= AMT_MAX_EVENTS;
+	queue_work(amt_wq, &amt->event_wq);
+	spin_unlock_bh(&amt->lock);
+
+	return 0;
+}
+
 static void amt_secret_work(struct work_struct *work)
 {
 	struct amt_dev *amt = container_of(to_delayed_work(work),
@@ -912,56 +927,72 @@ static void amt_secret_work(struct work_struct *work)
 			 msecs_to_jiffies(AMT_SECRET_TIMEOUT));
 }
 
-static void amt_discovery_work(struct work_struct *work)
+static void amt_event_send_discovery(struct amt_dev *amt)
 {
-	struct amt_dev *amt = container_of(to_delayed_work(work),
-					   struct amt_dev,
-					   discovery_wq);
-
-	spin_lock_bh(&amt->lock);
 	if (amt->status > AMT_STATUS_SENT_DISCOVERY)
 		goto out;
 	get_random_bytes(&amt->nonce, sizeof(__be32));
-	spin_unlock_bh(&amt->lock);
 
 	amt_send_discovery(amt);
-	spin_lock_bh(&amt->lock);
 out:
 	mod_delayed_work(amt_wq, &amt->discovery_wq,
 			 msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT));
-	spin_unlock_bh(&amt->lock);
 }
 
-static void amt_req_work(struct work_struct *work)
+static void amt_discovery_work(struct work_struct *work)
 {
 	struct amt_dev *amt = container_of(to_delayed_work(work),
 					   struct amt_dev,
-					   req_wq);
+					   discovery_wq);
+
+	if (amt_queue_event(amt, AMT_EVENT_SEND_DISCOVERY, NULL))
+		mod_delayed_work(amt_wq, &amt->discovery_wq,
+				 msecs_to_jiffies(AMT_DISCOVERY_TIMEOUT));
+}
+
+static void amt_event_send_request(struct amt_dev *amt)
+{
 	u32 exp;
 
-	spin_lock_bh(&amt->lock);
 	if (amt->status < AMT_STATUS_RECEIVED_ADVERTISEMENT)
 		goto out;
 
-	if (amt->req_cnt++ > AMT_MAX_REQ_COUNT) {
+	if (amt->req_cnt > AMT_MAX_REQ_COUNT) {
 		netdev_dbg(amt->dev, "Gateway is not ready");
 		amt->qi = AMT_INIT_REQ_TIMEOUT;
-		amt->ready4 = false;
-		amt->ready6 = false;
+		WRITE_ONCE(amt->ready4, false);
+		WRITE_ONCE(amt->ready6, false);
 		amt->remote_ip = 0;
-		__amt_update_gw_status(amt, AMT_STATUS_INIT, false);
+		amt_update_gw_status(amt, AMT_STATUS_INIT, false);
 		amt->req_cnt = 0;
+		amt->nonce = 0;
+		goto out;
+	}
+
+	if (!amt->req_cnt) {
+		WRITE_ONCE(amt->ready4, false);
+		WRITE_ONCE(amt->ready6, false);
+		get_random_bytes(&amt->nonce, sizeof(__be32));
 	}
-	spin_unlock_bh(&amt->lock);
 
 	amt_send_request(amt, false);
 	amt_send_request(amt, true);
 	amt_update_gw_status(amt, AMT_STATUS_SENT_REQUEST, true);
-	spin_lock_bh(&amt->lock);
+	amt->req_cnt++;
 out:
 	exp = min_t(u32, (1 * (1 << amt->req_cnt)), AMT_MAX_REQ_TIMEOUT);
-	mod_delayed_work(amt_wq, &amt->req_wq, msecs_to_jiffies(exp * 1000));
-	spin_unlock_bh(&amt->lock);
+	mod_delayed_work(amt_wq, &amt->req_wq, secs_to_jiffies(exp));
+}
+
+static void amt_req_work(struct work_struct *work)
+{
+	struct amt_dev *amt = container_of(to_delayed_work(work),
+					   struct amt_dev,
+					   req_wq);
+
+	if (amt_queue_event(amt, AMT_EVENT_SEND_REQUEST, NULL))
+		mod_delayed_work(amt_wq, &amt->req_wq,
+				 msecs_to_jiffies(100));
 }
 
 static bool amt_send_membership_update(struct amt_dev *amt,
@@ -989,7 +1020,7 @@ static bool amt_send_membership_update(struct amt_dev *amt,
 	fl4.flowi4_oif         = amt->stream_dev->ifindex;
 	fl4.daddr              = amt->remote_ip;
 	fl4.saddr              = amt->local_ip;
-	fl4.flowi4_tos         = AMT_TOS;
+	fl4.flowi4_dscp        = inet_dsfield_to_dscp(AMT_TOS);
 	fl4.flowi4_proto       = IPPROTO_UDP;
 	rt = ip_route_output_key(amt->net, &fl4);
 	if (IS_ERR(rt)) {
@@ -1017,7 +1048,8 @@ static bool amt_send_membership_update(struct amt_dev *amt,
 			    amt->gw_port,
 			    amt->relay_port,
 			    false,
-			    false);
+			    false,
+			    0);
 	amt_update_gw_status(amt, AMT_STATUS_SENT_UPDATE, true);
 	return false;
 }
@@ -1074,7 +1106,8 @@ static void amt_send_multicast_data(struct amt_dev *amt,
 			    amt->relay_port,
 			    tunnel->source_port,
 			    false,
-			    false);
+			    false,
+			    0);
 }
 
 static bool amt_send_membership_query(struct amt_dev *amt,
@@ -1102,7 +1135,7 @@ static bool amt_send_membership_query(struct amt_dev *amt,
 	fl4.flowi4_oif         = amt->stream_dev->ifindex;
 	fl4.daddr              = tunnel->ip4;
 	fl4.saddr              = amt->local_ip;
-	fl4.flowi4_tos         = AMT_TOS;
+	fl4.flowi4_dscp        = inet_dsfield_to_dscp(AMT_TOS);
 	fl4.flowi4_proto       = IPPROTO_UDP;
 	rt = ip_route_output_key(amt->net, &fl4);
 	if (IS_ERR(rt)) {
@@ -1132,7 +1165,8 @@ static bool amt_send_membership_query(struct amt_dev *amt,
 			    amt->relay_port,
 			    tunnel->source_port,
 			    false,
-			    false);
+			    false,
+			    0);
 	amt_update_relay_status(tunnel, AMT_STATUS_SENT_QUERY, true);
 	return false;
 }
@@ -1217,7 +1251,8 @@ static netdev_tx_t amt_dev_xmit(struct sk_buff *skb, struct net_device *dev)
 		/* Gateway only passes IGMP/MLD packets */
 		if (!report)
 			goto free;
-		if ((!v6 && !amt->ready4) || (v6 && !amt->ready6))
+		if ((!v6 && !READ_ONCE(amt->ready4)) ||
+		    (v6 && !READ_ONCE(amt->ready6)))
 			goto free;
 		if (amt_send_membership_update(amt, skb,  v6))
 			goto free;
@@ -1370,11 +1405,11 @@ static void amt_add_srcs(struct amt_dev *amt, struct amt_tunnel_list *tunnel,
 	int i;
 
 	if (!v6) {
-		igmp_grec = (struct igmpv3_grec *)grec;
+		igmp_grec = grec;
 		nsrcs = ntohs(igmp_grec->grec_nsrcs);
 	} else {
 #if IS_ENABLED(CONFIG_IPV6)
-		mld_grec = (struct mld2_grec *)grec;
+		mld_grec = grec;
 		nsrcs = ntohs(mld_grec->grec_nsrcs);
 #else
 	return;
@@ -1455,11 +1490,11 @@ static void amt_lookup_act_srcs(struct amt_tunnel_list *tunnel,
 	int i, j;
 
 	if (!v6) {
-		igmp_grec = (struct igmpv3_grec *)grec;
+		igmp_grec = grec;
 		nsrcs = ntohs(igmp_grec->grec_nsrcs);
 	} else {
 #if IS_ENABLED(CONFIG_IPV6)
-		mld_grec = (struct mld2_grec *)grec;
+		mld_grec = grec;
 		nsrcs = ntohs(mld_grec->grec_nsrcs);
 #else
 	return;
@@ -2218,8 +2253,7 @@ static bool amt_advertisement_handler(struct amt_dev *amt, struct sk_buff *skb)
 	struct amt_header_advertisement *amta;
 	int hdr_size;
 
-	hdr_size = sizeof(*amta) - sizeof(struct amt_header);
-
+	hdr_size = sizeof(*amta) + sizeof(struct udphdr);
 	if (!pskb_may_pull(skb, hdr_size))
 		return true;
 
@@ -2234,6 +2268,10 @@ static bool amt_advertisement_handler(struct amt_dev *amt, struct sk_buff *skb)
 	    ipv4_is_zeronet(amta->ip4))
 		return true;
 
+	if (amt->status != AMT_STATUS_SENT_DISCOVERY ||
+	    amt->nonce != amta->nonce)
+		return true;
+
 	amt->remote_ip = amta->ip4;
 	netdev_dbg(amt->dev, "advertised remote ip = %pI4\n", &amt->remote_ip);
 	mod_delayed_work(amt_wq, &amt->req_wq, 0);
@@ -2249,19 +2287,30 @@ static bool amt_multicast_data_handler(struct amt_dev *amt, struct sk_buff *skb)
 	struct ethhdr *eth;
 	struct iphdr *iph;
 
+	if (READ_ONCE(amt->status) != AMT_STATUS_SENT_UPDATE)
+		return true;
+
+	hdr_size = sizeof(*amtmd) + sizeof(struct udphdr);
+	if (!pskb_may_pull(skb, hdr_size))
+		return true;
+
 	amtmd = (struct amt_header_mcast_data *)(udp_hdr(skb) + 1);
 	if (amtmd->reserved || amtmd->version)
 		return true;
 
-	hdr_size = sizeof(*amtmd) + sizeof(struct udphdr);
 	if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_IP), false))
 		return true;
+
 	skb_reset_network_header(skb);
 	skb_push(skb, sizeof(*eth));
 	skb_reset_mac_header(skb);
 	skb_pull(skb, sizeof(*eth));
 	eth = eth_hdr(skb);
+
+	if (!pskb_may_pull(skb, sizeof(*iph)))
+		return true;
 	iph = ip_hdr(skb);
+
 	if (iph->version == 4) {
 		if (!ipv4_is_multicast(iph->daddr))
 			return true;
@@ -2272,6 +2321,9 @@ static bool amt_multicast_data_handler(struct amt_dev *amt, struct sk_buff *skb)
 	} else if (iph->version == 6) {
 		struct ipv6hdr *ip6h;
 
+		if (!pskb_may_pull(skb, sizeof(*ip6h)))
+			return true;
+
 		ip6h = ipv6_hdr(skb);
 		if (!ipv6_addr_is_multicast(&ip6h->daddr))
 			return true;
@@ -2304,8 +2356,7 @@ static bool amt_membership_query_handler(struct amt_dev *amt,
 	struct iphdr *iph;
 	int hdr_size, len;
 
-	hdr_size = sizeof(*amtmq) - sizeof(struct amt_header);
-
+	hdr_size = sizeof(*amtmq) + sizeof(struct udphdr);
 	if (!pskb_may_pull(skb, hdr_size))
 		return true;
 
@@ -2313,54 +2364,66 @@ static bool amt_membership_query_handler(struct amt_dev *amt,
 	if (amtmq->reserved || amtmq->version)
 		return true;
 
-	hdr_size = sizeof(*amtmq) + sizeof(struct udphdr) - sizeof(*eth);
+	if (amtmq->nonce != amt->nonce)
+		return true;
+
+	hdr_size -= sizeof(*eth);
 	if (iptunnel_pull_header(skb, hdr_size, htons(ETH_P_TEB), false))
 		return true;
+
 	oeth = eth_hdr(skb);
 	skb_reset_mac_header(skb);
 	skb_pull(skb, sizeof(*eth));
 	skb_reset_network_header(skb);
 	eth = eth_hdr(skb);
+	if (!pskb_may_pull(skb, sizeof(*iph)))
+		return true;
+
 	iph = ip_hdr(skb);
 	if (iph->version == 4) {
-		if (!ipv4_is_multicast(iph->daddr))
+		if (READ_ONCE(amt->ready4))
 			return true;
+
 		if (!pskb_may_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS +
 				   sizeof(*ihv3)))
 			return true;
 
+		if (!ipv4_is_multicast(iph->daddr))
+			return true;
+
 		ihv3 = skb_pull(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
 		skb_reset_transport_header(skb);
 		skb_push(skb, sizeof(*iph) + AMT_IPHDR_OPTS);
-		spin_lock_bh(&amt->lock);
-		amt->ready4 = true;
+		WRITE_ONCE(amt->ready4, true);
 		amt->mac = amtmq->response_mac;
 		amt->req_cnt = 0;
 		amt->qi = ihv3->qqic;
-		spin_unlock_bh(&amt->lock);
 		skb->protocol = htons(ETH_P_IP);
 		eth->h_proto = htons(ETH_P_IP);
 		ip_eth_mc_map(iph->daddr, eth->h_dest);
 #if IS_ENABLED(CONFIG_IPV6)
 	} else if (iph->version == 6) {
-		struct ipv6hdr *ip6h = ipv6_hdr(skb);
 		struct mld2_query *mld2q;
+		struct ipv6hdr *ip6h;
 
-		if (!ipv6_addr_is_multicast(&ip6h->daddr))
+		if (READ_ONCE(amt->ready6))
 			return true;
+
 		if (!pskb_may_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS +
 				   sizeof(*mld2q)))
 			return true;
 
+		ip6h = ipv6_hdr(skb);
+		if (!ipv6_addr_is_multicast(&ip6h->daddr))
+			return true;
+
 		mld2q = skb_pull(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
 		skb_reset_transport_header(skb);
 		skb_push(skb, sizeof(*ip6h) + AMT_IP6HDR_OPTS);
-		spin_lock_bh(&amt->lock);
-		amt->ready6 = true;
+		WRITE_ONCE(amt->ready6, true);
 		amt->mac = amtmq->response_mac;
 		amt->req_cnt = 0;
 		amt->qi = mld2q->mld2q_qqic;
-		spin_unlock_bh(&amt->lock);
 		skb->protocol = htons(ETH_P_IPV6);
 		eth->h_proto = htons(ETH_P_IPV6);
 		ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest);
@@ -2373,12 +2436,14 @@ static bool amt_membership_query_handler(struct amt_dev *amt,
 	skb->pkt_type = PACKET_MULTICAST;
 	skb->ip_summed = CHECKSUM_NONE;
 	len = skb->len;
-	if (netif_rx(skb) == NET_RX_SUCCESS) {
+	local_bh_disable();
+	if (__netif_rx(skb) == NET_RX_SUCCESS) {
 		amt_update_gw_status(amt, AMT_STATUS_RECEIVED_QUERY, true);
 		dev_sw_netstats_rx_add(amt->dev, len);
 	} else {
 		amt->dev->stats.rx_dropped++;
 	}
+	local_bh_enable();
 
 	return false;
 }
@@ -2387,23 +2452,23 @@ static bool amt_update_handler(struct amt_dev *amt, struct sk_buff *skb)
 {
 	struct amt_header_membership_update *amtmu;
 	struct amt_tunnel_list *tunnel;
-	struct udphdr *udph;
 	struct ethhdr *eth;
 	struct iphdr *iph;
-	int len;
+	int len, hdr_size;
 
 	iph = ip_hdr(skb);
-	udph = udp_hdr(skb);
 
-	if (__iptunnel_pull_header(skb, sizeof(*udph), skb->protocol,
-				   false, false))
+	hdr_size = sizeof(*amtmu) + sizeof(struct udphdr);
+	if (!pskb_may_pull(skb, hdr_size))
 		return true;
 
-	amtmu = (struct amt_header_membership_update *)skb->data;
+	amtmu = (struct amt_header_membership_update *)(udp_hdr(skb) + 1);
 	if (amtmu->reserved || amtmu->version)
 		return true;
 
-	skb_pull(skb, sizeof(*amtmu));
+	if (iptunnel_pull_header(skb, hdr_size, skb->protocol, false))
+		return true;
+
 	skb_reset_network_header(skb);
 
 	list_for_each_entry_rcu(tunnel, &amt->tunnel_list, list) {
@@ -2421,9 +2486,12 @@ static bool amt_update_handler(struct amt_dev *amt, struct sk_buff *skb)
 		}
 	}
 
-	return false;
+	return true;
 
 report:
+	if (!pskb_may_pull(skb, sizeof(*iph)))
+		return true;
+
 	iph = ip_hdr(skb);
 	if (iph->version == 4) {
 		if (ip_mc_check_igmp(skb)) {
@@ -2470,7 +2538,7 @@ report:
 	skb->pkt_type = PACKET_MULTICAST;
 	skb->ip_summed = CHECKSUM_NONE;
 	len = skb->len;
-	if (netif_rx(skb) == NET_RX_SUCCESS) {
+	if (__netif_rx(skb) == NET_RX_SUCCESS) {
 		amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_UPDATE,
 					true);
 		dev_sw_netstats_rx_add(amt->dev, len);
@@ -2616,7 +2684,9 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb)
 		if (tunnel->ip4 == iph->saddr)
 			goto send;
 
+	spin_lock_bh(&amt->lock);
 	if (amt->nr_tunnels >= amt->max_tunnels) {
+		spin_unlock_bh(&amt->lock);
 		icmp_ndo_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
 		return true;
 	}
@@ -2624,8 +2694,10 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb)
 	tunnel = kzalloc(sizeof(*tunnel) +
 			 (sizeof(struct hlist_head) * amt->hash_buckets),
 			 GFP_ATOMIC);
-	if (!tunnel)
+	if (!tunnel) {
+		spin_unlock_bh(&amt->lock);
 		return true;
+	}
 
 	tunnel->source_port = udph->source;
 	tunnel->ip4 = iph->saddr;
@@ -2638,10 +2710,9 @@ static bool amt_request_handler(struct amt_dev *amt, struct sk_buff *skb)
 
 	INIT_DELAYED_WORK(&tunnel->gc_wq, amt_tunnel_expire);
 
-	spin_lock_bh(&amt->lock);
 	list_add_tail_rcu(&tunnel->list, &amt->tunnel_list);
 	tunnel->key = amt->key;
-	amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true);
+	__amt_update_relay_status(tunnel, AMT_STATUS_RECEIVED_REQUEST, true);
 	amt->nr_tunnels++;
 	mod_delayed_work(amt_wq, &tunnel->gc_wq,
 			 msecs_to_jiffies(amt_gmi(amt)));
@@ -2666,6 +2737,38 @@ send:
 	return false;
 }
 
+static void amt_gw_rcv(struct amt_dev *amt, struct sk_buff *skb)
+{
+	int type = amt_parse_type(skb);
+	int err = 1;
+
+	if (type == -1)
+		goto drop;
+
+	if (amt->mode == AMT_MODE_GATEWAY) {
+		switch (type) {
+		case AMT_MSG_ADVERTISEMENT:
+			err = amt_advertisement_handler(amt, skb);
+			break;
+		case AMT_MSG_MEMBERSHIP_QUERY:
+			err = amt_membership_query_handler(amt, skb);
+			if (!err)
+				return;
+			break;
+		default:
+			netdev_dbg(amt->dev, "Invalid type of Gateway\n");
+			break;
+		}
+	}
+drop:
+	if (err) {
+		amt->dev->stats.rx_dropped++;
+		kfree_skb(skb);
+	} else {
+		consume_skb(skb);
+	}
+}
+
 static int amt_rcv(struct sock *sk, struct sk_buff *skb)
 {
 	struct amt_dev *amt;
@@ -2677,6 +2780,7 @@ static int amt_rcv(struct sock *sk, struct sk_buff *skb)
 	amt = rcu_dereference_sk_user_data(sk);
 	if (!amt) {
 		err = true;
+		kfree_skb(skb);
 		goto out;
 	}
 
@@ -2696,8 +2800,11 @@ static int amt_rcv(struct sock *sk, struct sk_buff *skb)
 				err = true;
 				goto drop;
 			}
-			if (amt_advertisement_handler(amt, skb))
-				amt->dev->stats.rx_dropped++;
+			if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) {
+				netdev_dbg(amt->dev, "AMT Event queue full\n");
+				err = true;
+				goto drop;
+			}
 			goto out;
 		case AMT_MSG_MULTICAST_DATA:
 			if (iph->saddr != amt->remote_ip) {
@@ -2716,11 +2823,12 @@ static int amt_rcv(struct sock *sk, struct sk_buff *skb)
 				err = true;
 				goto drop;
 			}
-			err = amt_membership_query_handler(amt, skb);
-			if (err)
+			if (amt_queue_event(amt, AMT_EVENT_RECEIVE, skb)) {
+				netdev_dbg(amt->dev, "AMT Event queue full\n");
+				err = true;
 				goto drop;
-			else
-				goto out;
+			}
+			goto out;
 		default:
 			err = true;
 			netdev_dbg(amt->dev, "Invalid type of Gateway\n");
@@ -2758,6 +2866,45 @@ out:
 	return 0;
 }
 
+static void amt_event_work(struct work_struct *work)
+{
+	struct amt_dev *amt = container_of(work, struct amt_dev, event_wq);
+	struct sk_buff *skb;
+	u8 event;
+	int i;
+
+	for (i = 0; i < AMT_MAX_EVENTS; i++) {
+		spin_lock_bh(&amt->lock);
+		if (amt->nr_events == 0) {
+			spin_unlock_bh(&amt->lock);
+			return;
+		}
+		event = amt->events[amt->event_idx].event;
+		skb = amt->events[amt->event_idx].skb;
+		amt->events[amt->event_idx].event = AMT_EVENT_NONE;
+		amt->events[amt->event_idx].skb = NULL;
+		amt->nr_events--;
+		amt->event_idx++;
+		amt->event_idx %= AMT_MAX_EVENTS;
+		spin_unlock_bh(&amt->lock);
+
+		switch (event) {
+		case AMT_EVENT_RECEIVE:
+			amt_gw_rcv(amt, skb);
+			break;
+		case AMT_EVENT_SEND_DISCOVERY:
+			amt_event_send_discovery(amt);
+			break;
+		case AMT_EVENT_SEND_REQUEST:
+			amt_event_send_request(amt);
+			break;
+		default:
+			kfree_skb(skb);
+			break;
+		}
+	}
+}
+
 static int amt_err_lookup(struct sock *sk, struct sk_buff *skb)
 {
 	struct amt_dev *amt;
@@ -2782,7 +2929,7 @@ static int amt_err_lookup(struct sock *sk, struct sk_buff *skb)
 		break;
 	case AMT_MSG_REQUEST:
 	case AMT_MSG_MEMBERSHIP_UPDATE:
-		if (amt->status >= AMT_STATUS_RECEIVED_ADVERTISEMENT)
+		if (READ_ONCE(amt->status) >= AMT_STATUS_RECEIVED_ADVERTISEMENT)
 			mod_delayed_work(amt_wq, &amt->req_wq, 0);
 		break;
 	default:
@@ -2845,6 +2992,8 @@ static int amt_dev_open(struct net_device *dev)
 
 	amt->ready4 = false;
 	amt->ready6 = false;
+	amt->event_idx = 0;
+	amt->nr_events = 0;
 
 	err = amt_socket_create(amt);
 	if (err)
@@ -2852,6 +3001,7 @@ static int amt_dev_open(struct net_device *dev)
 
 	amt->req_cnt = 0;
 	amt->remote_ip = 0;
+	amt->nonce = 0;
 	get_random_bytes(&amt->key, sizeof(siphash_key_t));
 
 	amt->status = AMT_STATUS_INIT;
@@ -2870,6 +3020,8 @@ static int amt_dev_stop(struct net_device *dev)
 	struct amt_dev *amt = netdev_priv(dev);
 	struct amt_tunnel_list *tunnel, *tmp;
 	struct socket *sock;
+	struct sk_buff *skb;
+	int i;
 
 	cancel_delayed_work_sync(&amt->req_wq);
 	cancel_delayed_work_sync(&amt->discovery_wq);
@@ -2882,6 +3034,14 @@ static int amt_dev_stop(struct net_device *dev)
 	if (sock)
 		udp_tunnel_sock_release(sock);
 
+	cancel_work_sync(&amt->event_wq);
+	for (i = 0; i < AMT_MAX_EVENTS; i++) {
+		skb = amt->events[i].skb;
+		kfree_skb(skb);
+		amt->events[i].event = AMT_EVENT_NONE;
+		amt->events[i].skb = NULL;
+	}
+
 	amt->ready4 = false;
 	amt->ready6 = false;
 	amt->req_cnt = 0;
@@ -2908,15 +3068,10 @@ static int amt_dev_init(struct net_device *dev)
 	int err;
 
 	amt->dev = dev;
-	dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
-	if (!dev->tstats)
-		return -ENOMEM;
 
 	err = gro_cells_init(&amt->gro_cells, dev);
-	if (err) {
-		free_percpu(dev->tstats);
+	if (err)
 		return err;
-	}
 
 	return 0;
 }
@@ -2926,7 +3081,6 @@ static void amt_dev_uninit(struct net_device *dev)
 	struct amt_dev *amt = netdev_priv(dev);
 
 	gro_cells_destroy(&amt->gro_cells);
-	free_percpu(dev->tstats);
 }
 
 static const struct net_device_ops amt_netdev_ops = {
@@ -2935,7 +3089,6 @@ static const struct net_device_ops amt_netdev_ops = {
 	.ndo_open		= amt_dev_open,
 	.ndo_stop		= amt_dev_stop,
 	.ndo_start_xmit         = amt_dev_xmit,
-	.ndo_get_stats64        = dev_get_tstats64,
 };
 
 static void amt_link_setup(struct net_device *dev)
@@ -2950,12 +3103,13 @@ static void amt_link_setup(struct net_device *dev)
 	dev->hard_header_len	= 0;
 	dev->addr_len		= 0;
 	dev->priv_flags		|= IFF_NO_QUEUE;
-	dev->features		|= NETIF_F_LLTX;
+	dev->lltx		= true;
+	dev->netns_immutable	= true;
 	dev->features		|= NETIF_F_GSO_SOFTWARE;
-	dev->features		|= NETIF_F_NETNS_LOCAL;
 	dev->hw_features	|= NETIF_F_SG | NETIF_F_HW_CSUM;
 	dev->hw_features	|= NETIF_F_FRAGLIST | NETIF_F_RXCSUM;
 	dev->hw_features	|= NETIF_F_GSO_SOFTWARE;
+	dev->pcpu_stat_type	= NETDEV_PCPU_STAT_TSTATS;
 	eth_hw_addr_random(dev);
 	eth_zero_addr(dev->broadcast);
 	ether_setup(dev);
@@ -3012,14 +3166,17 @@ static int amt_validate(struct nlattr *tb[], struct nlattr *data[],
 	return 0;
 }
 
-static int amt_newlink(struct net *net, struct net_device *dev,
-		       struct nlattr *tb[], struct nlattr *data[],
+static int amt_newlink(struct net_device *dev,
+		       struct rtnl_newlink_params *params,
 		       struct netlink_ext_ack *extack)
 {
+	struct net *link_net = rtnl_newlink_link_net(params);
 	struct amt_dev *amt = netdev_priv(dev);
+	struct nlattr **data = params->data;
+	struct nlattr **tb = params->tb;
 	int err = -EINVAL;
 
-	amt->net = net;
+	amt->net = link_net;
 	amt->mode = nla_get_u32(data[IFLA_AMT_MODE]);
 
 	if (data[IFLA_AMT_MAX_TUNNELS] &&
@@ -3034,7 +3191,7 @@ static int amt_newlink(struct net *net, struct net_device *dev,
 	amt->hash_buckets = AMT_HSIZE;
 	amt->nr_tunnels = 0;
 	get_random_bytes(&amt->hash_seed, sizeof(amt->hash_seed));
-	amt->stream_dev = dev_get_by_index(net,
+	amt->stream_dev = dev_get_by_index(link_net,
 					   nla_get_u32(data[IFLA_AMT_LINK]));
 	if (!amt->stream_dev) {
 		NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_LINK],
@@ -3057,15 +3214,11 @@ static int amt_newlink(struct net *net, struct net_device *dev,
 		goto err;
 	}
 
-	if (data[IFLA_AMT_RELAY_PORT])
-		amt->relay_port = nla_get_be16(data[IFLA_AMT_RELAY_PORT]);
-	else
-		amt->relay_port = htons(IANA_AMT_UDP_PORT);
+	amt->relay_port = nla_get_be16_default(data[IFLA_AMT_RELAY_PORT],
+					       htons(IANA_AMT_UDP_PORT));
 
-	if (data[IFLA_AMT_GATEWAY_PORT])
-		amt->gw_port = nla_get_be16(data[IFLA_AMT_GATEWAY_PORT]);
-	else
-		amt->gw_port = htons(IANA_AMT_UDP_PORT);
+	amt->gw_port = nla_get_be16_default(data[IFLA_AMT_GATEWAY_PORT],
+					    htons(IANA_AMT_UDP_PORT));
 
 	if (!amt->relay_port) {
 		NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_AMT_DISCOVERY_IP],
@@ -3073,7 +3226,7 @@ static int amt_newlink(struct net *net, struct net_device *dev,
 		goto err;
 	}
 	if (amt->mode == AMT_MODE_RELAY) {
-		amt->qrv = amt->net->ipv4.sysctl_igmp_qrv;
+		amt->qrv = READ_ONCE(amt->net->ipv4.sysctl_igmp_qrv);
 		amt->qri = 10;
 		dev->needed_headroom = amt->stream_dev->needed_headroom +
 				       AMT_RELAY_HLEN;
@@ -3124,8 +3277,8 @@ static int amt_newlink(struct net *net, struct net_device *dev,
 	INIT_DELAYED_WORK(&amt->discovery_wq, amt_discovery_work);
 	INIT_DELAYED_WORK(&amt->req_wq, amt_req_work);
 	INIT_DELAYED_WORK(&amt->secret_wq, amt_secret_work);
+	INIT_WORK(&amt->event_wq, amt_event_work);
 	INIT_LIST_HEAD(&amt->tunnel_list);
-
 	return 0;
 err:
 	dev_put(amt->stream_dev);
@@ -3258,7 +3411,7 @@ static int __init amt_init(void)
 	if (err < 0)
 		goto unregister_notifier;
 
-	amt_wq = alloc_workqueue("amt", WQ_UNBOUND, 1);
+	amt_wq = alloc_workqueue("amt", WQ_UNBOUND, 0);
 	if (!amt_wq) {
 		err = -ENOMEM;
 		goto rtnl_unregister;
@@ -3294,5 +3447,6 @@ static void __exit amt_fini(void)
 module_exit(amt_fini);
 
 MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Driver for Automatic Multicast Tunneling (AMT)");
 MODULE_AUTHOR("Taehee Yoo <ap420073@gmail.com>");
 MODULE_ALIAS_RTNL_LINK("amt");