diff --git a/include/net/udp.h b/include/net/udp.h
index 61222545ab1c..62a7207e65f2 100644
--- a/include/net/udp.h
+++ b/include/net/udp.h
@@ -50,7 +50,7 @@ struct udp_skb_cb {
 #define UDP_SKB_CB(__skb)	((struct udp_skb_cb *)((__skb)->cb))
 
 /**
- *	struct udp_hslot - UDP hash slot
+ *	struct udp_hslot - UDP hash slot used by udp_table.hash
  *
  *	@head:	head of list of sockets
  *	@count:	number of sockets in 'head' list
@@ -60,7 +60,22 @@ struct udp_hslot {
 	struct hlist_head	head;
 	int			count;
 	spinlock_t		lock;
-} __attribute__((aligned(2 * sizeof(long))));
+} __aligned(2 * sizeof(long));
+
+/**
+ *	struct udp_hslot_main - UDP hash slot used by udp_table.hash2
+ *
+ *	@hslot:	basic hash slot
+ *	@hash4_cnt: number of sockets in hslot4 of the same
+ *		    (local port, local address)
+ */
+struct udp_hslot_main {
+	struct udp_hslot	hslot; /* must be the first member */
+#if !IS_ENABLED(CONFIG_BASE_SMALL)
+	u32			hash4_cnt;
+#endif
+} __aligned(2 * sizeof(long));
+#define UDP_HSLOT_MAIN(__hslot) ((struct udp_hslot_main *)(__hslot))
 
 /**
  *	struct udp_table - UDP table
@@ -72,7 +87,7 @@ struct udp_hslot {
  */
 struct udp_table {
 	struct udp_hslot	*hash;
-	struct udp_hslot	*hash2;
+	struct udp_hslot_main	*hash2;
 	unsigned int		mask;
 	unsigned int		log;
 };
@@ -84,6 +99,7 @@ static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
 {
 	return &table->hash[udp_hashfn(net, num, table->mask)];
 }
+
 /*
  * For secondary hash, net_hash_mix() is performed before calling
  * udp_hashslot2(), this explains difference with udp_hashslot()
@@ -91,9 +107,23 @@ static inline struct udp_hslot *udp_hashslot(struct udp_table *table,
 static inline struct udp_hslot *udp_hashslot2(struct udp_table *table,
 					      unsigned int hash)
 {
-	return &table->hash2[hash & table->mask];
+	return &table->hash2[hash & table->mask].hslot;
 }
 
+#if IS_ENABLED(CONFIG_BASE_SMALL)
+static inline void udp_table_hash4_init(struct udp_table *table)
+{
+}
+#else /* !CONFIG_BASE_SMALL */
+
+/* Must be called with table->hash2 initialized */
+static inline void udp_table_hash4_init(struct udp_table *table)
+{
+	for (int i = 0; i <= table->mask; i++)
+		table->hash2[i].hash4_cnt = 0;
+}
+#endif /* CONFIG_BASE_SMALL */
+
 extern struct proto udp_prot;
 
 extern atomic_long_t udp_memory_allocated;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 0e24916b39d4..2fdac5fae2a8 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -486,13 +486,12 @@ struct sock *__udp4_lib_lookup(const struct net *net, __be32 saddr,
 		int sdif, struct udp_table *udptable, struct sk_buff *skb)
 {
 	unsigned short hnum = ntohs(dport);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
 	struct sock *result, *sk;
+	unsigned int hash2;
 
 	hash2 = ipv4_portaddr_hash(net, daddr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 
 	/* Lookup connected or non-wildcard socket */
 	result = udp4_lib_lookup2(net, saddr, sport,
@@ -519,8 +518,7 @@ struct sock *__udp4_lib_lookup(const struct net *net, __be32 saddr,
 
 	/* Lookup wildcard sockets */
 	hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 
 	result = udp4_lib_lookup2(net, saddr, sport,
 				  htonl(INADDR_ANY), hnum, dif, sdif,
@@ -2268,7 +2266,7 @@ static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 			    udptable->mask;
 		hash2 = ipv4_portaddr_hash(net, daddr, hnum) & udptable->mask;
 start_lookup:
-		hslot = &udptable->hash2[hash2];
+		hslot = &udptable->hash2[hash2].hslot;
 		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 	}
 
@@ -2539,14 +2537,13 @@ static struct sock *__udp4_lib_demux_lookup(struct net *net,
 	struct udp_table *udptable = net->ipv4.udp_table;
 	INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr);
 	unsigned short hnum = ntohs(loc_port);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
+	unsigned int hash2;
 	__portpair ports;
 	struct sock *sk;
 
 	hash2 = ipv4_portaddr_hash(net, loc_addr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 	ports = INET_COMBINED_PORTS(rmt_port, hnum);
 
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
@@ -3187,7 +3184,7 @@ static struct sock *bpf_iter_udp_batch(struct seq_file *seq)
 	batch_sks = 0;
 
 	for (; state->bucket <= udptable->mask; state->bucket++) {
-		struct udp_hslot *hslot2 = &udptable->hash2[state->bucket];
+		struct udp_hslot *hslot2 = &udptable->hash2[state->bucket].hslot;
 
 		if (hlist_empty(&hslot2->head))
 			continue;
@@ -3428,10 +3425,11 @@ __setup("uhash_entries=", set_uhash_entries);
 
 void __init udp_table_init(struct udp_table *table, const char *name)
 {
-	unsigned int i;
+	unsigned int i, slot_size;
 
+	slot_size = sizeof(struct udp_hslot) + sizeof(struct udp_hslot_main);
 	table->hash = alloc_large_system_hash(name,
-					      2 * sizeof(struct udp_hslot),
+					      slot_size,
 					      uhash_entries,
 					      21, /* one slot per 2 MB */
 					      0,
@@ -3440,17 +3438,18 @@ void __init udp_table_init(struct udp_table *table, const char *name)
 					      UDP_HTABLE_SIZE_MIN,
 					      UDP_HTABLE_SIZE_MAX);
 
-	table->hash2 = table->hash + (table->mask + 1);
+	table->hash2 = (void *)(table->hash + (table->mask + 1));
 	for (i = 0; i <= table->mask; i++) {
 		INIT_HLIST_HEAD(&table->hash[i].head);
 		table->hash[i].count = 0;
 		spin_lock_init(&table->hash[i].lock);
 	}
 	for (i = 0; i <= table->mask; i++) {
-		INIT_HLIST_HEAD(&table->hash2[i].head);
-		table->hash2[i].count = 0;
-		spin_lock_init(&table->hash2[i].lock);
+		INIT_HLIST_HEAD(&table->hash2[i].hslot.head);
+		table->hash2[i].hslot.count = 0;
+		spin_lock_init(&table->hash2[i].hslot.lock);
 	}
+	udp_table_hash4_init(table);
 }
 
 u32 udp_flow_hashrnd(void)
@@ -3476,18 +3475,20 @@ static void __net_init udp_sysctl_init(struct net *net)
 static struct udp_table __net_init *udp_pernet_table_alloc(unsigned int hash_entries)
 {
 	struct udp_table *udptable;
+	unsigned int slot_size;
 	int i;
 
 	udptable = kmalloc(sizeof(*udptable), GFP_KERNEL);
 	if (!udptable)
 		goto out;
 
-	udptable->hash = vmalloc_huge(hash_entries * 2 * sizeof(struct udp_hslot),
+	slot_size = sizeof(struct udp_hslot) + sizeof(struct udp_hslot_main);
+	udptable->hash = vmalloc_huge(hash_entries * slot_size,
 				      GFP_KERNEL_ACCOUNT);
 	if (!udptable->hash)
 		goto free_table;
 
-	udptable->hash2 = udptable->hash + hash_entries;
+	udptable->hash2 = (void *)(udptable->hash + hash_entries);
 	udptable->mask = hash_entries - 1;
 	udptable->log = ilog2(hash_entries);
 
@@ -3496,10 +3497,11 @@ static struct udp_table __net_init *udp_pernet_table_alloc(unsigned int hash_ent
 		udptable->hash[i].count = 0;
 		spin_lock_init(&udptable->hash[i].lock);
 
-		INIT_HLIST_HEAD(&udptable->hash2[i].head);
-		udptable->hash2[i].count = 0;
-		spin_lock_init(&udptable->hash2[i].lock);
+		INIT_HLIST_HEAD(&udptable->hash2[i].hslot.head);
+		udptable->hash2[i].hslot.count = 0;
+		spin_lock_init(&udptable->hash2[i].hslot.lock);
 	}
+	udp_table_hash4_init(udptable);
 
 	return udptable;
 
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 0cef8ae5d1ea..0d7aac9d44e5 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -224,13 +224,12 @@ struct sock *__udp6_lib_lookup(const struct net *net,
 			       struct sk_buff *skb)
 {
 	unsigned short hnum = ntohs(dport);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
 	struct sock *result, *sk;
+	unsigned int hash2;
 
 	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 
 	/* Lookup connected or non-wildcard sockets */
 	result = udp6_lib_lookup2(net, saddr, sport,
@@ -257,8 +256,7 @@ struct sock *__udp6_lib_lookup(const struct net *net,
 
 	/* Lookup wildcard sockets */
 	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 
 	result = udp6_lib_lookup2(net, saddr, sport,
 				  &in6addr_any, hnum, dif, sdif,
@@ -859,7 +857,7 @@ static int __udp6_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
 			    udptable->mask;
 		hash2 = ipv6_portaddr_hash(net, daddr, hnum) & udptable->mask;
 start_lookup:
-		hslot = &udptable->hash2[hash2];
+		hslot = &udptable->hash2[hash2].hslot;
 		offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
 	}
 
@@ -1065,14 +1063,13 @@ static struct sock *__udp6_lib_demux_lookup(struct net *net,
 {
 	struct udp_table *udptable = net->ipv4.udp_table;
 	unsigned short hnum = ntohs(loc_port);
-	unsigned int hash2, slot2;
 	struct udp_hslot *hslot2;
+	unsigned int hash2;
 	__portpair ports;
 	struct sock *sk;
 
 	hash2 = ipv6_portaddr_hash(net, loc_addr, hnum);
-	slot2 = hash2 & udptable->mask;
-	hslot2 = &udptable->hash2[slot2];
+	hslot2 = udp_hashslot2(udptable, hash2);
 	ports = INET_COMBINED_PORTS(rmt_port, hnum);
 
 	udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {