1 files changed, 113 insertions, 31 deletions

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index c438908..dc45b53 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -113,6 +113,7 @@
 #include <trace/events/skb.h>
 #include <net/busy_poll.h>
 #include "udp_impl.h"
+#include <net/sock_reuseport.h>
 
 struct udp_table udp_table __read_mostly;
 EXPORT_SYMBOL(udp_table);
@@ -137,7 +138,8 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
 			       unsigned long *bitmap,
 			       struct sock *sk,
 			       int (*saddr_comp)(const struct sock *sk1,
-						 const struct sock *sk2),
+						 const struct sock *sk2,
+						 bool match_wildcard),
 			       unsigned int log)
 {
 	struct sock *sk2;
@@ -152,8 +154,9 @@ static int udp_lib_lport_inuse(struct net *net, __u16 num,
 		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
 		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 		    (!sk2->sk_reuseport || !sk->sk_reuseport ||
+		     rcu_access_pointer(sk->sk_reuseport_cb) ||
 		     !uid_eq(uid, sock_i_uid(sk2))) &&
-		    saddr_comp(sk, sk2)) {
+		    saddr_comp(sk, sk2, true)) {
 			if (!bitmap)
 				return 1;
 			__set_bit(udp_sk(sk2)->udp_port_hash >> log, bitmap);
@@ -170,7 +173,8 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 				struct udp_hslot *hslot2,
 				struct sock *sk,
 				int (*saddr_comp)(const struct sock *sk1,
-						  const struct sock *sk2))
+						  const struct sock *sk2,
+						  bool match_wildcard))
 {
 	struct sock *sk2;
 	struct hlist_nulls_node *node;
@@ -186,8 +190,9 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 		    (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
 		     sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 		    (!sk2->sk_reuseport || !sk->sk_reuseport ||
+		     rcu_access_pointer(sk->sk_reuseport_cb) ||
 		     !uid_eq(uid, sock_i_uid(sk2))) &&
-		    saddr_comp(sk, sk2)) {
+		    saddr_comp(sk, sk2, true)) {
 			res = 1;
 			break;
 		}
@@ -196,6 +201,35 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
 	return res;
 }
 
+static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot,
+				  int (*saddr_same)(const struct sock *sk1,
+						    const struct sock *sk2,
+						    bool match_wildcard))
+{
+	struct net *net = sock_net(sk);
+	struct hlist_nulls_node *node;
+	kuid_t uid = sock_i_uid(sk);
+	struct sock *sk2;
+
+	sk_nulls_for_each(sk2, node, &hslot->head) {
+		if (net_eq(sock_net(sk2), net) &&
+		    sk2 != sk &&
+		    sk2->sk_family == sk->sk_family &&
+		    ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
+		    (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) &&
+		    (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
+		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
+		    (*saddr_same)(sk, sk2, false)) {
+			return reuseport_add_sock(sk, sk2);
+		}
+	}
+
+	/* Initial allocation may have already happened via setsockopt */
+	if (!rcu_access_pointer(sk->sk_reuseport_cb))
+		return reuseport_alloc(sk);
+	return 0;
+}
+
 /**
  *  udp_lib_get_port  -  UDP/-Lite port lookup for IPv4 and IPv6
  *
@@ -207,7 +241,8 @@ static int udp_lib_lport_inuse2(struct net *net, __u16 num,
  */
 int udp_lib_get_port(struct sock *sk, unsigned short snum,
 		     int (*saddr_comp)(const struct sock *sk1,
-				       const struct sock *sk2),
+				       const struct sock *sk2,
+				       bool match_wildcard),
 		     unsigned int hash2_nulladdr)
 {
 	struct udp_hslot *hslot, *hslot2;
@@ -290,6 +325,14 @@ found:
 	udp_sk(sk)->udp_port_hash = snum;
 	udp_sk(sk)->udp_portaddr_hash ^= snum;
 	if (sk_unhashed(sk)) {
+		if (sk->sk_reuseport &&
+		    udp_reuseport_add_sock(sk, hslot, saddr_comp)) {
+			inet_sk(sk)->inet_num = 0;
+			udp_sk(sk)->udp_port_hash = 0;
+			udp_sk(sk)->udp_portaddr_hash ^= snum;
+			goto fail_unlock;
+		}
+
 		sk_nulls_add_node_rcu(sk, &hslot->head);
 		hslot->count++;
 		sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
@@ -309,13 +352,22 @@ fail:
 }
 EXPORT_SYMBOL(udp_lib_get_port);
 
-static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2)
+/* match_wildcard == true:  0.0.0.0 equals to any IPv4 addresses
+ * match_wildcard == false: addresses must be exactly the same, i.e.
+ *                          0.0.0.0 only equals to 0.0.0.0
+ */
+static int ipv4_rcv_saddr_equal(const struct sock *sk1, const struct sock *sk2,
+				bool match_wildcard)
 {
 	struct inet_sock *inet1 = inet_sk(sk1), *inet2 = inet_sk(sk2);
 
-	return 	(!ipv6_only_sock(sk2)  &&
-		 (!inet1->inet_rcv_saddr || !inet2->inet_rcv_saddr ||
-		   inet1->inet_rcv_saddr == inet2->inet_rcv_saddr));
+	if (!ipv6_only_sock(sk2)) {
+		if (inet1->inet_rcv_saddr == inet2->inet_rcv_saddr)
+			return 1;
+		if (!inet1->inet_rcv_saddr || !inet2->inet_rcv_saddr)
+			return match_wildcard;
+	}
+	return 0;
 }
 
 static u32 udp4_portaddr_hash(const struct net *net, __be32 saddr,
@@ -441,7 +493,8 @@ static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
 static struct sock *udp4_lib_lookup2(struct net *net,
 		__be32 saddr, __be16 sport,
 		__be32 daddr, unsigned int hnum, int dif,
-		struct udp_hslot *hslot2, unsigned int slot2)
+		struct udp_hslot *hslot2, unsigned int slot2,
+		struct sk_buff *skb)
 {
 	struct sock *sk, *result;
 	struct hlist_nulls_node *node;
@@ -459,8 +512,15 @@ begin:
 			badness = score;
 			reuseport = sk->sk_reuseport;
 			if (reuseport) {
+				struct sock *sk2;
 				hash = udp_ehashfn(net, daddr, hnum,
 						   saddr, sport);
+				sk2 = reuseport_select_sock(sk, hash, skb,
+							    sizeof(struct udphdr));
+				if (sk2) {
+					result = sk2;
+					goto found;
+				}
 				matches = 1;
 			}
 		} else if (score == badness && reuseport) {
@@ -478,6 +538,7 @@ begin:
 	if (get_nulls_value(node) != slot2)
 		goto begin;
 	if (result) {
+found:
 		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 			result = NULL;
 		else if (unlikely(compute_score2(result, net, saddr, sport,
@@ -494,7 +555,7 @@ begin:
  */
 struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 		__be16 sport, __be32 daddr, __be16 dport,
-		int dif, struct udp_table *udptable)
+		int dif, struct udp_table *udptable, struct sk_buff *skb)
 {
 	struct sock *sk, *result;
 	struct hlist_nulls_node *node;
@@ -514,7 +575,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 
 		result = udp4_lib_lookup2(net, saddr, sport,
 					  daddr, hnum, dif,
-					  hslot2, slot2);
+					  hslot2, slot2, skb);
 		if (!result) {
 			hash2 = udp4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
 			slot2 = hash2 & udptable->mask;
@@ -524,7 +585,7 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 
 			result = udp4_lib_lookup2(net, saddr, sport,
 						  htonl(INADDR_ANY), hnum, dif,
-						  hslot2, slot2);
+						  hslot2, slot2, skb);
 		}
 		rcu_read_unlock();
 		return result;
@@ -540,8 +601,15 @@ begin:
 			badness = score;
 			reuseport = sk->sk_reuseport;
 			if (reuseport) {
+				struct sock *sk2;
 				hash = udp_ehashfn(net, daddr, hnum,
 						   saddr, sport);
+				sk2 = reuseport_select_sock(sk, hash, skb,
+							sizeof(struct udphdr));
+				if (sk2) {
+					result = sk2;
+					goto found;
+				}
 				matches = 1;
 			}
 		} else if (score == badness && reuseport) {
@@ -560,6 +628,7 @@ begin:
 		goto begin;
 
 	if (result) {
+found:
 		if (unlikely(!atomic_inc_not_zero_hint(&result->sk_refcnt, 2)))
 			result = NULL;
 		else if (unlikely(compute_score(result, net, saddr, hnum, sport,
@@ -581,13 +650,14 @@ static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
 
 	return __udp4_lib_lookup(dev_net(skb_dst(skb)->dev), iph->saddr, sport,
 				 iph->daddr, dport, inet_iif(skb),
-				 udptable);
+				 udptable, skb);
 }
 
 struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
 			     __be32 daddr, __be16 dport, int dif)
 {
-	return __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif, &udp_table);
+	return __udp4_lib_lookup(net, saddr, sport, daddr, dport, dif,
+				 &udp_table, NULL);
 }
 EXPORT_SYMBOL_GPL(udp4_lib_lookup);
 
@@ -635,7 +705,8 @@ void __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
 	struct net *net = dev_net(skb->dev);
 
 	sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
-			iph->saddr, uh->source, skb->dev->ifindex, udptable);
+			iph->saddr, uh->source, skb->dev->ifindex, udptable,
+			NULL);
 	if (!sk) {
 		ICMP_INC_STATS_BH(net, ICMP_MIB_INERRORS);
 		return;	/* No socket for error */
@@ -772,7 +843,8 @@ void udp_set_csum(bool nocheck, struct sk_buff *skb,
 	else if (skb_is_gso(skb))
 		uh->check = ~udp_v4_check(len, saddr, daddr, 0);
 	else if (skb_dst(skb) && skb_dst(skb)->dev &&
-		 (skb_dst(skb)->dev->features & NETIF_F_V4_CSUM)) {
+		 (skb_dst(skb)->dev->features &
+		  (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) {
 
 		BUG_ON(skb->ip_summed == CHECKSUM_PARTIAL);
 
@@ -1273,6 +1345,7 @@ int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int noblock,
 	int peeked, off = 0;
 	int err;
 	int is_udplite = IS_UDPLITE(sk);
+	bool checksum_valid = false;
 	bool slow;
 
 	if (flags & MSG_ERRQUEUE)
@@ -1298,11 +1371,12 @@ try_again:
 	 */
 
 	if (copied < ulen || UDP_SKB_CB(skb)->partial_cov) {
-		if (udp_lib_checksum_complete(skb))
+		checksum_valid = !udp_lib_checksum_complete(skb);
+		if (!checksum_valid)
 			goto csum_copy_err;
 	}
 
-	if (skb_csum_unnecessary(skb))
+	if (checksum_valid || skb_csum_unnecessary(skb))
 		err = skb_copy_datagram_msg(skb, sizeof(struct udphdr),
 					    msg, copied);
 	else {
@@ -1398,6 +1472,8 @@ void udp_lib_unhash(struct sock *sk)
 		hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
 
 		spin_lock_bh(&hslot->lock);
+		if (rcu_access_pointer(sk->sk_reuseport_cb))
+			reuseport_detach_sock(sk);
 		if (sk_nulls_del_node_init_rcu(sk)) {
 			hslot->count--;
 			inet_sk(sk)->inet_num = 0;
@@ -1425,22 +1501,28 @@ void udp_lib_rehash(struct sock *sk, u16 newhash)
 		hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
 		nhslot2 = udp_hashslot2(udptable, newhash);
 		udp_sk(sk)->udp_portaddr_hash = newhash;
-		if (hslot2 != nhslot2) {
+
+		if (hslot2 != nhslot2 ||
+		    rcu_access_pointer(sk->sk_reuseport_cb)) {
 			hslot = udp_hashslot(udptable, sock_net(sk),
 					     udp_sk(sk)->udp_port_hash);
 			/* we must lock primary chain too */
 			spin_lock_bh(&hslot->lock);
-
-			spin_lock(&hslot2->lock);
-			hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
-			hslot2->count--;
-			spin_unlock(&hslot2->lock);
-
-			spin_lock(&nhslot2->lock);
-			hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
-						 &nhslot2->head);
-			nhslot2->count++;
-			spin_unlock(&nhslot2->lock);
+			if (rcu_access_pointer(sk->sk_reuseport_cb))
+				reuseport_detach_sock(sk);
+
+			if (hslot2 != nhslot2) {
+				spin_lock(&hslot2->lock);
+				hlist_nulls_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
+				hslot2->count--;
+				spin_unlock(&hslot2->lock);
+
+				spin_lock(&nhslot2->lock);
+				hlist_nulls_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
+							 &nhslot2->head);
+				nhslot2->count++;
+				spin_unlock(&nhslot2->lock);
+			}
 
 			spin_unlock_bh(&hslot->lock);
 		}