Merge branch 'bpf-reuseport-map'

Martin KaFai Lau says:

====================
This series introduces a new map type "BPF_MAP_TYPE_REUSEPORT_SOCKARRAY"
and a new prog type BPF_PROG_TYPE_SK_REUSEPORT.

Here is a snippet from a commit message:

"To unleash the full potential of a bpf prog, it is essential for the
userspace to be capable of directly setting up a bpf map which can then
be consumed by the bpf prog to make decision.  In this case, decide which
SO_REUSEPORT sk to serve the incoming request.

By adding BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, the userspace has total control
and visibility on where a SO_REUSEPORT sk should be located in a bpf map.
The later patch will introduce BPF_PROG_TYPE_SK_REUSEPORT such that
the bpf prog can directly select a sk from the bpf map.  That will
raise the programmability of the bpf prog attached to a reuseport
group (a group of sk serving the same IP:PORT).

For example, in UDP, the bpf prog can peek into the payload (e.g.
through the "data" pointer introduced in the later patch) to learn
the application level's connection information and then decide which sk
to pick from a bpf map.  The userspace can tightly couple the sk's location
in a bpf map with the application logic in generating the UDP payload's
connection information.  This connection info contact/API stays within the
userspace.

Also, when used with map-in-map, the userspace can switch the
old-server-process's inner map to a new-server-process's inner map
in one call "bpf_map_update_elem(outer_map, &index, &new_reuseport_array)".
The bpf prog will then direct incoming requests to the new process instead
of the old process.  The old process can finish draining the pending
requests (e.g. by "accept()") before closing the old-fds.  [Note that
deleting a fd from a bpf map does not necessary mean the fd is closed]"
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

35 files changed, 2167 insertions, 97 deletions

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index cd8790d2c6ed..db11662faea6 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -524,6 +524,7 @@ static inline int bpf_map_attr_numa_node(const union bpf_attr *attr)
 }
 
 struct bpf_prog *bpf_prog_get_type_path(const char *name, enum bpf_prog_type type);
+int array_map_alloc_check(union bpf_attr *attr);
 
 #else /* !CONFIG_BPF_SYSCALL */
 static inline struct bpf_prog *bpf_prog_get(u32 ufd)
@@ -769,6 +770,33 @@ static inline void __xsk_map_flush(struct bpf_map *map)
 }
 #endif
 
+#if defined(CONFIG_INET) && defined(CONFIG_BPF_SYSCALL)
+void bpf_sk_reuseport_detach(struct sock *sk);
+int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map, void *key,
+				       void *value);
+int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
+				       void *value, u64 map_flags);
+#else
+static inline void bpf_sk_reuseport_detach(struct sock *sk)
+{
+}
+
+#ifdef CONFIG_BPF_SYSCALL
+static inline int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map,
+						     void *key, void *value)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int bpf_fd_reuseport_array_update_elem(struct bpf_map *map,
+						     void *key, void *value,
+						     u64 map_flags)
+{
+	return -EOPNOTSUPP;
+}
+#endif /* CONFIG_BPF_SYSCALL */
+#endif /* defined(CONFIG_INET) && defined(CONFIG_BPF_SYSCALL) */
+
 /* verifier prototypes for helper functions called from eBPF programs */
 extern const struct bpf_func_proto bpf_map_lookup_elem_proto;
 extern const struct bpf_func_proto bpf_map_update_elem_proto;
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index add08be53b6f..cd26c090e7c0 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -29,6 +29,9 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_CGROUP_DEVICE, cg_dev)
 #ifdef CONFIG_BPF_LIRC_MODE2
 BPF_PROG_TYPE(BPF_PROG_TYPE_LIRC_MODE2, lirc_mode2)
 #endif
+#ifdef CONFIG_INET
+BPF_PROG_TYPE(BPF_PROG_TYPE_SK_REUSEPORT, sk_reuseport)
+#endif
 
 BPF_MAP_TYPE(BPF_MAP_TYPE_ARRAY, array_map_ops)
 BPF_MAP_TYPE(BPF_MAP_TYPE_PERCPU_ARRAY, percpu_array_map_ops)
@@ -60,4 +63,7 @@ BPF_MAP_TYPE(BPF_MAP_TYPE_CPUMAP, cpu_map_ops)
 #if defined(CONFIG_XDP_SOCKETS)
 BPF_MAP_TYPE(BPF_MAP_TYPE_XSKMAP, xsk_map_ops)
 #endif
+#ifdef CONFIG_INET
+BPF_MAP_TYPE(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY, reuseport_array_ops)
+#endif
 #endif
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 2b072dab32c0..5d565c50bcb2 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -32,6 +32,7 @@ struct seccomp_data;
 struct bpf_prog_aux;
 struct xdp_rxq_info;
 struct xdp_buff;
+struct sock_reuseport;
 
 /* ArgX, context and stack frame pointer register positions. Note,
  * Arg1, Arg2, Arg3, etc are used as argument mappings of function
@@ -752,6 +753,7 @@ int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 int sk_attach_bpf(u32 ufd, struct sock *sk);
 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk);
 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk);
+void sk_reuseport_prog_free(struct bpf_prog *prog);
 int sk_detach_filter(struct sock *sk);
 int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
 		  unsigned int len);
@@ -833,6 +835,20 @@ void bpf_warn_invalid_xdp_action(u32 act);
 struct sock *do_sk_redirect_map(struct sk_buff *skb);
 struct sock *do_msg_redirect_map(struct sk_msg_buff *md);
 
+#ifdef CONFIG_INET
+struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
+				  struct bpf_prog *prog, struct sk_buff *skb,
+				  u32 hash);
+#else
+static inline struct sock *
+bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
+		     struct bpf_prog *prog, struct sk_buff *skb,
+		     u32 hash)
+{
+	return NULL;
+}
+#endif
+
 #ifdef CONFIG_BPF_JIT
 extern int bpf_jit_enable;
 extern int bpf_jit_harden;
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 5f43f7a70fe6..6def0351bcc3 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -108,6 +108,7 @@ int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
 		    u32 banned_flags);
 bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
 			  bool match_wildcard);
+bool inet_rcv_saddr_any(const struct sock *sk);
 void addrconf_join_solict(struct net_device *dev, const struct in6_addr *addr);
 void addrconf_leave_solict(struct inet6_dev *idev, const struct in6_addr *addr);
 
diff --git a/include/net/sock_reuseport.h b/include/net/sock_reuseport.h
index 0054b3a9b923..8a5f70c7cdf2 100644
--- a/include/net/sock_reuseport.h
+++ b/include/net/sock_reuseport.h
@@ -5,25 +5,36 @@
 #include <linux/filter.h>
 #include <linux/skbuff.h>
 #include <linux/types.h>
+#include <linux/spinlock.h>
 #include <net/sock.h>
 
+extern spinlock_t reuseport_lock;
+
 struct sock_reuseport {
 	struct rcu_head		rcu;
 
 	u16			max_socks;	/* length of socks */
 	u16			num_socks;	/* elements in socks */
+	/* The last synq overflow event timestamp of this
+	 * reuse->socks[] group.
+	 */
+	unsigned int		synq_overflow_ts;
+	/* ID stays the same even after the size of socks[] grows. */
+	unsigned int		reuseport_id;
+	bool			bind_inany;
 	struct bpf_prog __rcu	*prog;		/* optional BPF sock selector */
 	struct sock		*socks[0];	/* array of sock pointers */
 };
 
-extern int reuseport_alloc(struct sock *sk);
-extern int reuseport_add_sock(struct sock *sk, struct sock *sk2);
+extern int reuseport_alloc(struct sock *sk, bool bind_inany);
+extern int reuseport_add_sock(struct sock *sk, struct sock *sk2,
+			      bool bind_inany);
 extern void reuseport_detach_sock(struct sock *sk);
 extern struct sock *reuseport_select_sock(struct sock *sk,
 					  u32 hash,
 					  struct sk_buff *skb,
 					  int hdr_len);
-extern struct bpf_prog *reuseport_attach_prog(struct sock *sk,
-					      struct bpf_prog *prog);
+extern int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog);
+int reuseport_get_id(struct sock_reuseport *reuse);
 
 #endif  /* _SOCK_REUSEPORT_H */
diff --git a/include/net/tcp.h b/include/net/tcp.h
index d769dc20359b..d196901c9dba 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -36,6 +36,7 @@
 #include <net/inet_hashtables.h>
 #include <net/checksum.h>
 #include <net/request_sock.h>
+#include <net/sock_reuseport.h>
 #include <net/sock.h>
 #include <net/snmp.h>
 #include <net/ip.h>
@@ -473,9 +474,22 @@ struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb);
  */
 static inline void tcp_synq_overflow(const struct sock *sk)
 {
-	unsigned int last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
+	unsigned int last_overflow;
 	unsigned int now = jiffies;
 
+	if (sk->sk_reuseport) {
+		struct sock_reuseport *reuse;
+
+		reuse = rcu_dereference(sk->sk_reuseport_cb);
+		if (likely(reuse)) {
+			last_overflow = READ_ONCE(reuse->synq_overflow_ts);
+			if (time_after32(now, last_overflow + HZ))
+				WRITE_ONCE(reuse->synq_overflow_ts, now);
+			return;
+		}
+	}
+
+	last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
 	if (time_after32(now, last_overflow + HZ))
 		tcp_sk(sk)->rx_opt.ts_recent_stamp = now;
 }
@@ -483,9 +497,21 @@ static inline void tcp_synq_overflow(const struct sock *sk)
 /* syncookies: no recent synqueue overflow on this listening socket? */
 static inline bool tcp_synq_no_recent_overflow(const struct sock *sk)
 {
-	unsigned int last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
+	unsigned int last_overflow;
 	unsigned int now = jiffies;
 
+	if (sk->sk_reuseport) {
+		struct sock_reuseport *reuse;
+
+		reuse = rcu_dereference(sk->sk_reuseport_cb);
+		if (likely(reuse)) {
+			last_overflow = READ_ONCE(reuse->synq_overflow_ts);
+			return time_after32(now, last_overflow +
+					    TCP_SYNCOOKIE_VALID);
+		}
+	}
+
+	last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
 	return time_after32(now, last_overflow + TCP_SYNCOOKIE_VALID);
 }
 
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index dd5758dc35d3..3102a2a23c31 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -126,6 +126,7 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_XSKMAP,
 	BPF_MAP_TYPE_SOCKHASH,
 	BPF_MAP_TYPE_CGROUP_STORAGE,
+	BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
 };
 
 enum bpf_prog_type {
@@ -150,6 +151,7 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
 	BPF_PROG_TYPE_LWT_SEG6LOCAL,
 	BPF_PROG_TYPE_LIRC_MODE2,
+	BPF_PROG_TYPE_SK_REUSEPORT,
 };
 
 enum bpf_attach_type {
@@ -2113,6 +2115,14 @@ union bpf_attr {
  *		the shared data.
  *	Return
  *		Pointer to the local storage area.
+ *
+ * int bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags)
+ *	Description
+ *		Select a SO_REUSEPORT sk from a	BPF_MAP_TYPE_REUSEPORT_ARRAY map
+ *		It checks the selected sk is matching the incoming
+ *		request in the skb.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2196,7 +2206,8 @@ union bpf_attr {
 	FN(rc_keydown),			\
 	FN(skb_cgroup_id),		\
 	FN(get_current_cgroup_id),	\
-	FN(get_local_storage),
+	FN(get_local_storage),		\
+	FN(sk_select_reuseport),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -2413,6 +2424,30 @@ struct sk_msg_md {
 	__u32 local_port;	/* stored in host byte order */
 };
 
+struct sk_reuseport_md {
+	/*
+	 * Start of directly accessible data. It begins from
+	 * the tcp/udp header.
+	 */
+	void *data;
+	void *data_end;		/* End of directly accessible data */
+	/*
+	 * Total length of packet (starting from the tcp/udp header).
+	 * Note that the directly accessible bytes (data_end - data)
+	 * could be less than this "len".  Those bytes could be
+	 * indirectly read by a helper "bpf_skb_load_bytes()".
+	 */
+	__u32 len;
+	/*
+	 * Eth protocol in the mac header (network byte order). e.g.
+	 * ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD)
+	 */
+	__u32 eth_protocol;
+	__u32 ip_protocol;	/* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */
+	__u32 bind_inany;	/* Is sock bound to an INANY address? */
+	__u32 hash;		/* A hash of the packet 4 tuples */
+};
+
 #define BPF_TAG_SIZE	8
 
 struct bpf_prog_info {
diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile
index e8906cbad81f..0488b8258321 100644
--- a/kernel/bpf/Makefile
+++ b/kernel/bpf/Makefile
@@ -23,3 +23,6 @@ ifeq ($(CONFIG_PERF_EVENTS),y)
 obj-$(CONFIG_BPF_SYSCALL) += stackmap.o
 endif
 obj-$(CONFIG_CGROUP_BPF) += cgroup.o
+ifeq ($(CONFIG_INET),y)
+obj-$(CONFIG_BPF_SYSCALL) += reuseport_array.o
+endif
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index 2aa55d030c77..f6ca3e712831 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -54,7 +54,7 @@ static int bpf_array_alloc_percpu(struct bpf_array *array)
 }
 
 /* Called from syscall */
-static int array_map_alloc_check(union bpf_attr *attr)
+int array_map_alloc_check(union bpf_attr *attr)
 {
 	bool percpu = attr->map_type == BPF_MAP_TYPE_PERCPU_ARRAY;
 	int numa_node = bpf_map_attr_numa_node(attr);
diff --git a/kernel/bpf/reuseport_array.c b/kernel/bpf/reuseport_array.c
new file mode 100644
index 000000000000..18e225de80ff
--- /dev/null
+++ b/kernel/bpf/reuseport_array.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Facebook
+ */
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <linux/sock_diag.h>
+#include <net/sock_reuseport.h>
+
+struct reuseport_array {
+	struct bpf_map map;
+	struct sock __rcu *ptrs[];
+};
+
+static struct reuseport_array *reuseport_array(struct bpf_map *map)
+{
+	return (struct reuseport_array *)map;
+}
+
+/* The caller must hold the reuseport_lock */
+void bpf_sk_reuseport_detach(struct sock *sk)
+{
+	struct sock __rcu **socks;
+
+	write_lock_bh(&sk->sk_callback_lock);
+	socks = sk->sk_user_data;
+	if (socks) {
+		WRITE_ONCE(sk->sk_user_data, NULL);
+		/*
+		 * Do not move this NULL assignment outside of
+		 * sk->sk_callback_lock because there is
+		 * a race with reuseport_array_free()
+		 * which does not hold the reuseport_lock.
+		 */
+		RCU_INIT_POINTER(*socks, NULL);
+	}
+	write_unlock_bh(&sk->sk_callback_lock);
+}
+
+static int reuseport_array_alloc_check(union bpf_attr *attr)
+{
+	if (attr->value_size != sizeof(u32) &&
+	    attr->value_size != sizeof(u64))
+		return -EINVAL;
+
+	return array_map_alloc_check(attr);
+}
+
+static void *reuseport_array_lookup_elem(struct bpf_map *map, void *key)
+{
+	struct reuseport_array *array = reuseport_array(map);
+	u32 index = *(u32 *)key;
+
+	if (unlikely(index >= array->map.max_entries))
+		return NULL;
+
+	return rcu_dereference(array->ptrs[index]);
+}
+
+/* Called from syscall only */
+static int reuseport_array_delete_elem(struct bpf_map *map, void *key)
+{
+	struct reuseport_array *array = reuseport_array(map);
+	u32 index = *(u32 *)key;
+	struct sock *sk;
+	int err;
+
+	if (index >= map->max_entries)
+		return -E2BIG;
+
+	if (!rcu_access_pointer(array->ptrs[index]))
+		return -ENOENT;
+
+	spin_lock_bh(&reuseport_lock);
+
+	sk = rcu_dereference_protected(array->ptrs[index],
+				       lockdep_is_held(&reuseport_lock));
+	if (sk) {
+		write_lock_bh(&sk->sk_callback_lock);
+		WRITE_ONCE(sk->sk_user_data, NULL);
+		RCU_INIT_POINTER(array->ptrs[index], NULL);
+		write_unlock_bh(&sk->sk_callback_lock);
+		err = 0;
+	} else {
+		err = -ENOENT;
+	}
+
+	spin_unlock_bh(&reuseport_lock);
+
+	return err;
+}
+
+static void reuseport_array_free(struct bpf_map *map)
+{
+	struct reuseport_array *array = reuseport_array(map);
+	struct sock *sk;
+	u32 i;
+
+	synchronize_rcu();
+
+	/*
+	 * ops->map_*_elem() will not be able to access this
+	 * array now. Hence, this function only races with
+	 * bpf_sk_reuseport_detach() which was triggerred by
+	 * close() or disconnect().
+	 *
+	 * This function and bpf_sk_reuseport_detach() are
+	 * both removing sk from "array".  Who removes it
+	 * first does not matter.
+	 *
+	 * The only concern here is bpf_sk_reuseport_detach()
+	 * may access "array" which is being freed here.
+	 * bpf_sk_reuseport_detach() access this "array"
+	 * through sk->sk_user_data _and_ with sk->sk_callback_lock
+	 * held which is enough because this "array" is not freed
+	 * until all sk->sk_user_data has stopped referencing this "array".
+	 *
+	 * Hence, due to the above, taking "reuseport_lock" is not
+	 * needed here.
+	 */
+
+	/*
+	 * Since reuseport_lock is not taken, sk is accessed under
+	 * rcu_read_lock()
+	 */
+	rcu_read_lock();
+	for (i = 0; i < map->max_entries; i++) {
+		sk = rcu_dereference(array->ptrs[i]);
+		if (sk) {
+			write_lock_bh(&sk->sk_callback_lock);
+			/*
+			 * No need for WRITE_ONCE(). At this point,
+			 * no one is reading it without taking the
+			 * sk->sk_callback_lock.
+			 */
+			sk->sk_user_data = NULL;
+			write_unlock_bh(&sk->sk_callback_lock);
+			RCU_INIT_POINTER(array->ptrs[i], NULL);
+		}
+	}
+	rcu_read_unlock();
+
+	/*
+	 * Once reaching here, all sk->sk_user_data is not
+	 * referenceing this "array".  "array" can be freed now.
+	 */
+	bpf_map_area_free(array);
+}
+
+static struct bpf_map *reuseport_array_alloc(union bpf_attr *attr)
+{
+	int err, numa_node = bpf_map_attr_numa_node(attr);
+	struct reuseport_array *array;
+	u64 cost, array_size;
+
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	array_size = sizeof(*array);
+	array_size += (u64)attr->max_entries * sizeof(struct sock *);
+
+	/* make sure there is no u32 overflow later in round_up() */
+	cost = array_size;
+	if (cost >= U32_MAX - PAGE_SIZE)
+		return ERR_PTR(-ENOMEM);
+	cost = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
+
+	err = bpf_map_precharge_memlock(cost);
+	if (err)
+		return ERR_PTR(err);
+
+	/* allocate all map elements and zero-initialize them */
+	array = bpf_map_area_alloc(array_size, numa_node);
+	if (!array)
+		return ERR_PTR(-ENOMEM);
+
+	/* copy mandatory map attributes */
+	bpf_map_init_from_attr(&array->map, attr);
+	array->map.pages = cost;
+
+	return &array->map;
+}
+
+int bpf_fd_reuseport_array_lookup_elem(struct bpf_map *map, void *key,
+				       void *value)
+{
+	struct sock *sk;
+	int err;
+
+	if (map->value_size != sizeof(u64))
+		return -ENOSPC;
+
+	rcu_read_lock();
+	sk = reuseport_array_lookup_elem(map, key);
+	if (sk) {
+		*(u64 *)value = sock_gen_cookie(sk);
+		err = 0;
+	} else {
+		err = -ENOENT;
+	}
+	rcu_read_unlock();
+
+	return err;
+}
+
+static int
+reuseport_array_update_check(const struct reuseport_array *array,
+			     const struct sock *nsk,
+			     const struct sock *osk,
+			     const struct sock_reuseport *nsk_reuse,
+			     u32 map_flags)
+{
+	if (osk && map_flags == BPF_NOEXIST)
+		return -EEXIST;
+
+	if (!osk && map_flags == BPF_EXIST)
+		return -ENOENT;
+
+	if (nsk->sk_protocol != IPPROTO_UDP && nsk->sk_protocol != IPPROTO_TCP)
+		return -ENOTSUPP;
+
+	if (nsk->sk_family != AF_INET && nsk->sk_family != AF_INET6)
+		return -ENOTSUPP;
+
+	if (nsk->sk_type != SOCK_STREAM && nsk->sk_type != SOCK_DGRAM)
+		return -ENOTSUPP;
+
+	/*
+	 * sk must be hashed (i.e. listening in the TCP case or binded
+	 * in the UDP case) and
+	 * it must also be a SO_REUSEPORT sk (i.e. reuse cannot be NULL).
+	 *
+	 * Also, sk will be used in bpf helper that is protected by
+	 * rcu_read_lock().
+	 */
+	if (!sock_flag(nsk, SOCK_RCU_FREE) || !sk_hashed(nsk) || !nsk_reuse)
+		return -EINVAL;
+
+	/* READ_ONCE because the sk->sk_callback_lock may not be held here */
+	if (READ_ONCE(nsk->sk_user_data))
+		return -EBUSY;
+
+	return 0;
+}
+
+/*
+ * Called from syscall only.
+ * The "nsk" in the fd refcnt.
+ * The "osk" and "reuse" are protected by reuseport_lock.
+ */
+int bpf_fd_reuseport_array_update_elem(struct bpf_map *map, void *key,
+				       void *value, u64 map_flags)
+{
+	struct reuseport_array *array = reuseport_array(map);
+	struct sock *free_osk = NULL, *osk, *nsk;
+	struct sock_reuseport *reuse;
+	u32 index = *(u32 *)key;
+	struct socket *socket;
+	int err, fd;
+
+	if (map_flags > BPF_EXIST)
+		return -EINVAL;
+
+	if (index >= map->max_entries)
+		return -E2BIG;
+
+	if (map->value_size == sizeof(u64)) {
+		u64 fd64 = *(u64 *)value;
+
+		if (fd64 > S32_MAX)
+			return -EINVAL;
+		fd = fd64;
+	} else {
+		fd = *(int *)value;
+	}
+
+	socket = sockfd_lookup(fd, &err);
+	if (!socket)
+		return err;
+
+	nsk = socket->sk;
+	if (!nsk) {
+		err = -EINVAL;
+		goto put_file;
+	}
+
+	/* Quick checks before taking reuseport_lock */
+	err = reuseport_array_update_check(array, nsk,
+					   rcu_access_pointer(array->ptrs[index]),
+					   rcu_access_pointer(nsk->sk_reuseport_cb),
+					   map_flags);
+	if (err)
+		goto put_file;
+
+	spin_lock_bh(&reuseport_lock);
+	/*
+	 * Some of the checks only need reuseport_lock
+	 * but it is done under sk_callback_lock also
+	 * for simplicity reason.
+	 */
+	write_lock_bh(&nsk->sk_callback_lock);
+
+	osk = rcu_dereference_protected(array->ptrs[index],
+					lockdep_is_held(&reuseport_lock));
+	reuse = rcu_dereference_protected(nsk->sk_reuseport_cb,
+					  lockdep_is_held(&reuseport_lock));
+	err = reuseport_array_update_check(array, nsk, osk, reuse, map_flags);
+	if (err)
+		goto put_file_unlock;
+
+	/* Ensure reuse->reuseport_id is set */
+	err = reuseport_get_id(reuse);
+	if (err < 0)
+		goto put_file_unlock;
+
+	WRITE_ONCE(nsk->sk_user_data, &array->ptrs[index]);
+	rcu_assign_pointer(array->ptrs[index], nsk);
+	free_osk = osk;
+	err = 0;
+
+put_file_unlock:
+	write_unlock_bh(&nsk->sk_callback_lock);
+
+	if (free_osk) {
+		write_lock_bh(&free_osk->sk_callback_lock);
+		WRITE_ONCE(free_osk->sk_user_data, NULL);
+		write_unlock_bh(&free_osk->sk_callback_lock);
+	}
+
+	spin_unlock_bh(&reuseport_lock);
+put_file:
+	fput(socket->file);
+	return err;
+}
+
+/* Called from syscall */
+static int reuseport_array_get_next_key(struct bpf_map *map, void *key,
+					void *next_key)
+{
+	struct reuseport_array *array = reuseport_array(map);
+	u32 index = key ? *(u32 *)key : U32_MAX;
+	u32 *next = (u32 *)next_key;
+
+	if (index >= array->map.max_entries) {
+		*next = 0;
+		return 0;
+	}
+
+	if (index == array->map.max_entries - 1)
+		return -ENOENT;
+
+	*next = index + 1;
+	return 0;
+}
+
+const struct bpf_map_ops reuseport_array_ops = {
+	.map_alloc_check = reuseport_array_alloc_check,
+	.map_alloc = reuseport_array_alloc,
+	.map_free = reuseport_array_free,
+	.map_lookup_elem = reuseport_array_lookup_elem,
+	.map_get_next_key = reuseport_array_get_next_key,
+	.map_delete_elem = reuseport_array_delete_elem,
+};
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5af4e9e2722d..57f4d076141b 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -684,6 +684,8 @@ static int map_lookup_elem(union bpf_attr *attr)
 		err = bpf_fd_array_map_lookup_elem(map, key, value);
 	} else if (IS_FD_HASH(map)) {
 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
+	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
+		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
 	} else {
 		rcu_read_lock();
 		ptr = map->ops->map_lookup_elem(map, key);
@@ -790,6 +792,10 @@ static int map_update_elem(union bpf_attr *attr)
 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
 						  attr->flags);
 		rcu_read_unlock();
+	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
+		/* rcu_read_lock() is not needed */
+		err = bpf_fd_reuseport_array_update_elem(map, key, value,
+							 attr->flags);
 	} else {
 		rcu_read_lock();
 		err = map->ops->map_update_elem(map, key, value, attr->flags);
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 587468a9c37d..ca90679a7fe5 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1310,6 +1310,7 @@ static bool may_access_direct_pkt_data(struct bpf_verifier_env *env,
 	case BPF_PROG_TYPE_LWT_IN:
 	case BPF_PROG_TYPE_LWT_OUT:
 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
+	case BPF_PROG_TYPE_SK_REUSEPORT:
 		/* dst_input() and dst_output() can't write for now */
 		if (t == BPF_WRITE)
 			return false;
@@ -2166,6 +2167,10 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
 		    func_id != BPF_FUNC_msg_redirect_hash)
 			goto error;
 		break;
+	case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
+		if (func_id != BPF_FUNC_sk_select_reuseport)
+			goto error;
+		break;
 	default:
 		break;
 	}
@@ -2217,6 +2222,10 @@ static int check_map_func_compatibility(struct bpf_verifier_env *env,
 		if (map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE)
 			goto error;
 		break;
+	case BPF_FUNC_sk_select_reuseport:
+		if (map->map_type != BPF_MAP_TYPE_REUSEPORT_SOCKARRAY)
+			goto error;
+		break;
 	default:
 		break;
 	}
diff --git a/net/core/filter.c b/net/core/filter.c
index 2de7dd9f2a57..22906b31d43f 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -1453,30 +1453,6 @@ static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
 	return 0;
 }
 
-static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
-{
-	struct bpf_prog *old_prog;
-	int err;
-
-	if (bpf_prog_size(prog->len) > sysctl_optmem_max)
-		return -ENOMEM;
-
-	if (sk_unhashed(sk) && sk->sk_reuseport) {
-		err = reuseport_alloc(sk);
-		if (err)
-			return err;
-	} else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
-		/* The socket wasn't bound with SO_REUSEPORT */
-		return -EINVAL;
-	}
-
-	old_prog = reuseport_attach_prog(sk, prog);
-	if (old_prog)
-		bpf_prog_destroy(old_prog);
-
-	return 0;
-}
-
 static
 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
 {
@@ -1550,13 +1526,15 @@ int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
 	if (IS_ERR(prog))
 		return PTR_ERR(prog);
 
-	err = __reuseport_attach_prog(prog, sk);
-	if (err < 0) {
+	if (bpf_prog_size(prog->len) > sysctl_optmem_max)
+		err = -ENOMEM;
+	else
+		err = reuseport_attach_prog(sk, prog);
+
+	if (err)
 		__bpf_prog_release(prog);
-		return err;
-	}
 
-	return 0;
+	return err;
 }
 
 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
@@ -1586,19 +1564,58 @@ int sk_attach_bpf(u32 ufd, struct sock *sk)
 
 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
 {
-	struct bpf_prog *prog = __get_bpf(ufd, sk);
+	struct bpf_prog *prog;
 	int err;
 
+	if (sock_flag(sk, SOCK_FILTER_LOCKED))
+		return -EPERM;
+
+	prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
+	if (IS_ERR(prog) && PTR_ERR(prog) == -EINVAL)
+		prog = bpf_prog_get_type(ufd, BPF_PROG_TYPE_SK_REUSEPORT);
 	if (IS_ERR(prog))
 		return PTR_ERR(prog);
 
-	err = __reuseport_attach_prog(prog, sk);
-	if (err < 0) {
-		bpf_prog_put(prog);
-		return err;
+	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT) {
+		/* Like other non BPF_PROG_TYPE_SOCKET_FILTER
+		 * bpf prog (e.g. sockmap).  It depends on the
+		 * limitation imposed by bpf_prog_load().
+		 * Hence, sysctl_optmem_max is not checked.
+		 */
+		if ((sk->sk_type != SOCK_STREAM &&
+		     sk->sk_type != SOCK_DGRAM) ||
+		    (sk->sk_protocol != IPPROTO_UDP &&
+		     sk->sk_protocol != IPPROTO_TCP) ||
+		    (sk->sk_family != AF_INET &&
+		     sk->sk_family != AF_INET6)) {
+			err = -ENOTSUPP;
+			goto err_prog_put;
+		}
+	} else {
+		/* BPF_PROG_TYPE_SOCKET_FILTER */
+		if (bpf_prog_size(prog->len) > sysctl_optmem_max) {
+			err = -ENOMEM;
+			goto err_prog_put;
+		}
 	}
 
-	return 0;
+	err = reuseport_attach_prog(sk, prog);
+err_prog_put:
+	if (err)
+		bpf_prog_put(prog);
+
+	return err;
+}
+
+void sk_reuseport_prog_free(struct bpf_prog *prog)
+{
+	if (!prog)
+		return;
+
+	if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
+		bpf_prog_put(prog);
+	else
+		bpf_prog_destroy(prog);
 }
 
 struct bpf_scratchpad {
@@ -7013,3 +7030,270 @@ out:
 	release_sock(sk);
 	return ret;
 }
+
+#ifdef CONFIG_INET
+struct sk_reuseport_kern {
+	struct sk_buff *skb;
+	struct sock *sk;
+	struct sock *selected_sk;
+	void *data_end;
+	u32 hash;
+	u32 reuseport_id;
+	bool bind_inany;
+};
+
+static void bpf_init_reuseport_kern(struct sk_reuseport_kern *reuse_kern,
+				    struct sock_reuseport *reuse,
+				    struct sock *sk, struct sk_buff *skb,
+				    u32 hash)
+{
+	reuse_kern->skb = skb;
+	reuse_kern->sk = sk;
+	reuse_kern->selected_sk = NULL;
+	reuse_kern->data_end = skb->data + skb_headlen(skb);
+	reuse_kern->hash = hash;
+	reuse_kern->reuseport_id = reuse->reuseport_id;
+	reuse_kern->bind_inany = reuse->bind_inany;
+}
+
+struct sock *bpf_run_sk_reuseport(struct sock_reuseport *reuse, struct sock *sk,
+				  struct bpf_prog *prog, struct sk_buff *skb,
+				  u32 hash)
+{
+	struct sk_reuseport_kern reuse_kern;
+	enum sk_action action;
+
+	bpf_init_reuseport_kern(&reuse_kern, reuse, sk, skb, hash);
+	action = BPF_PROG_RUN(prog, &reuse_kern);
+
+	if (action == SK_PASS)
+		return reuse_kern.selected_sk;
+	else
+		return ERR_PTR(-ECONNREFUSED);
+}
+
+BPF_CALL_4(sk_select_reuseport, struct sk_reuseport_kern *, reuse_kern,
+	   struct bpf_map *, map, void *, key, u32, flags)
+{
+	struct sock_reuseport *reuse;
+	struct sock *selected_sk;
+
+	selected_sk = map->ops->map_lookup_elem(map, key);
+	if (!selected_sk)
+		return -ENOENT;
+
+	reuse = rcu_dereference(selected_sk->sk_reuseport_cb);
+	if (!reuse)
+		/* selected_sk is unhashed (e.g. by close()) after the
+		 * above map_lookup_elem().  Treat selected_sk has already
+		 * been removed from the map.
+		 */
+		return -ENOENT;
+
+	if (unlikely(reuse->reuseport_id != reuse_kern->reuseport_id)) {
+		struct sock *sk;
+
+		if (unlikely(!reuse_kern->reuseport_id))
+			/* There is a small race between adding the
+			 * sk to the map and setting the
+			 * reuse_kern->reuseport_id.
+			 * Treat it as the sk has not been added to
+			 * the bpf map yet.
+			 */
+			return -ENOENT;
+
+		sk = reuse_kern->sk;
+		if (sk->sk_protocol != selected_sk->sk_protocol)
+			return -EPROTOTYPE;
+		else if (sk->sk_family != selected_sk->sk_family)
+			return -EAFNOSUPPORT;
+
+		/* Catch all. Likely bound to a different sockaddr. */
+		return -EBADFD;
+	}
+
+	reuse_kern->selected_sk = selected_sk;
+
+	return 0;
+}
+
+static const struct bpf_func_proto sk_select_reuseport_proto = {
+	.func           = sk_select_reuseport,
+	.gpl_only       = false,
+	.ret_type       = RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type      = ARG_CONST_MAP_PTR,
+	.arg3_type      = ARG_PTR_TO_MAP_KEY,
+	.arg4_type	= ARG_ANYTHING,
+};
+
+BPF_CALL_4(sk_reuseport_load_bytes,
+	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
+	   void *, to, u32, len)
+{
+	return ____bpf_skb_load_bytes(reuse_kern->skb, offset, to, len);
+}
+
+static const struct bpf_func_proto sk_reuseport_load_bytes_proto = {
+	.func		= sk_reuseport_load_bytes,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type	= ARG_ANYTHING,
+	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
+	.arg4_type	= ARG_CONST_SIZE,
+};
+
+BPF_CALL_5(sk_reuseport_load_bytes_relative,
+	   const struct sk_reuseport_kern *, reuse_kern, u32, offset,
+	   void *, to, u32, len, u32, start_header)
+{
+	return ____bpf_skb_load_bytes_relative(reuse_kern->skb, offset, to,
+					       len, start_header);
+}
+
+static const struct bpf_func_proto sk_reuseport_load_bytes_relative_proto = {
+	.func		= sk_reuseport_load_bytes_relative,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+	.arg2_type	= ARG_ANYTHING,
+	.arg3_type	= ARG_PTR_TO_UNINIT_MEM,
+	.arg4_type	= ARG_CONST_SIZE,
+	.arg5_type	= ARG_ANYTHING,
+};
+
+static const struct bpf_func_proto *
+sk_reuseport_func_proto(enum bpf_func_id func_id,
+			const struct bpf_prog *prog)
+{
+	switch (func_id) {
+	case BPF_FUNC_sk_select_reuseport:
+		return &sk_select_reuseport_proto;
+	case BPF_FUNC_skb_load_bytes:
+		return &sk_reuseport_load_bytes_proto;
+	case BPF_FUNC_skb_load_bytes_relative:
+		return &sk_reuseport_load_bytes_relative_proto;
+	default:
+		return bpf_base_func_proto(func_id);
+	}
+}
+
+static bool
+sk_reuseport_is_valid_access(int off, int size,
+			     enum bpf_access_type type,
+			     const struct bpf_prog *prog,
+			     struct bpf_insn_access_aux *info)
+{
+	const u32 size_default = sizeof(__u32);
+
+	if (off < 0 || off >= sizeof(struct sk_reuseport_md) ||
+	    off % size || type != BPF_READ)
+		return false;
+
+	switch (off) {
+	case offsetof(struct sk_reuseport_md, data):
+		info->reg_type = PTR_TO_PACKET;
+		return size == sizeof(__u64);
+
+	case offsetof(struct sk_reuseport_md, data_end):
+		info->reg_type = PTR_TO_PACKET_END;
+		return size == sizeof(__u64);
+
+	case offsetof(struct sk_reuseport_md, hash):
+		return size == size_default;
+
+	/* Fields that allow narrowing */
+	case offsetof(struct sk_reuseport_md, eth_protocol):
+		if (size < FIELD_SIZEOF(struct sk_buff, protocol))
+			return false;
+	case offsetof(struct sk_reuseport_md, ip_protocol):
+	case offsetof(struct sk_reuseport_md, bind_inany):
+	case offsetof(struct sk_reuseport_md, len):
+		bpf_ctx_record_field_size(info, size_default);
+		return bpf_ctx_narrow_access_ok(off, size, size_default);
+
+	default:
+		return false;
+	}
+}
+
+#define SK_REUSEPORT_LOAD_FIELD(F) ({					\
+	*insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_reuseport_kern, F), \
+			      si->dst_reg, si->src_reg,			\
+			      bpf_target_off(struct sk_reuseport_kern, F, \
+					     FIELD_SIZEOF(struct sk_reuseport_kern, F), \
+					     target_size));		\
+	})
+
+#define SK_REUSEPORT_LOAD_SKB_FIELD(SKB_FIELD)				\
+	SOCK_ADDR_LOAD_NESTED_FIELD(struct sk_reuseport_kern,		\
+				    struct sk_buff,			\
+				    skb,				\
+				    SKB_FIELD)
+
+#define SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(SK_FIELD, BPF_SIZE, EXTRA_OFF) \
+	SOCK_ADDR_LOAD_NESTED_FIELD_SIZE_OFF(struct sk_reuseport_kern,	\
+					     struct sock,		\
+					     sk,			\
+					     SK_FIELD, BPF_SIZE, EXTRA_OFF)
+
+static u32 sk_reuseport_convert_ctx_access(enum bpf_access_type type,
+					   const struct bpf_insn *si,
+					   struct bpf_insn *insn_buf,
+					   struct bpf_prog *prog,
+					   u32 *target_size)
+{
+	struct bpf_insn *insn = insn_buf;
+
+	switch (si->off) {
+	case offsetof(struct sk_reuseport_md, data):
+		SK_REUSEPORT_LOAD_SKB_FIELD(data);
+		break;
+
+	case offsetof(struct sk_reuseport_md, len):
+		SK_REUSEPORT_LOAD_SKB_FIELD(len);
+		break;
+
+	case offsetof(struct sk_reuseport_md, eth_protocol):
+		SK_REUSEPORT_LOAD_SKB_FIELD(protocol);
+		break;
+
+	case offsetof(struct sk_reuseport_md, ip_protocol):
+		BUILD_BUG_ON(hweight_long(SK_FL_PROTO_MASK) != BITS_PER_BYTE);
+		SK_REUSEPORT_LOAD_SK_FIELD_SIZE_OFF(__sk_flags_offset,
+						    BPF_W, 0);
+		*insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
+		*insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg,
+					SK_FL_PROTO_SHIFT);
+		/* SK_FL_PROTO_MASK and SK_FL_PROTO_SHIFT are endian
+		 * aware.  No further narrowing or masking is needed.
+		 */
+		*target_size = 1;
+		break;
+
+	case offsetof(struct sk_reuseport_md, data_end):
+		SK_REUSEPORT_LOAD_FIELD(data_end);
+		break;
+
+	case offsetof(struct sk_reuseport_md, hash):
+		SK_REUSEPORT_LOAD_FIELD(hash);
+		break;
+
+	case offsetof(struct sk_reuseport_md, bind_inany):
+		SK_REUSEPORT_LOAD_FIELD(bind_inany);
+		break;
+	}
+
+	return insn - insn_buf;
+}
+
+const struct bpf_verifier_ops sk_reuseport_verifier_ops = {
+	.get_func_proto		= sk_reuseport_func_proto,
+	.is_valid_access	= sk_reuseport_is_valid_access,
+	.convert_ctx_access	= sk_reuseport_convert_ctx_access,
+};
+
+const struct bpf_prog_ops sk_reuseport_prog_ops = {
+};
+#endif /* CONFIG_INET */
diff --git a/net/core/sock_reuseport.c b/net/core/sock_reuseport.c
index 064acb04be0f..ba5cba56f574 100644
--- a/net/core/sock_reuseport.c
+++ b/net/core/sock_reuseport.c
@@ -8,11 +8,34 @@
 
 #include <net/sock_reuseport.h>
 #include <linux/bpf.h>
+#include <linux/idr.h>
+#include <linux/filter.h>
 #include <linux/rcupdate.h>
 
 #define INIT_SOCKS 128
 
-static DEFINE_SPINLOCK(reuseport_lock);
+DEFINE_SPINLOCK(reuseport_lock);
+
+#define REUSEPORT_MIN_ID 1
+static DEFINE_IDA(reuseport_ida);
+
+int reuseport_get_id(struct sock_reuseport *reuse)
+{
+	int id;
+
+	if (reuse->reuseport_id)
+		return reuse->reuseport_id;
+
+	id = ida_simple_get(&reuseport_ida, REUSEPORT_MIN_ID, 0,
+			    /* Called under reuseport_lock */
+			    GFP_ATOMIC);
+	if (id < 0)
+		return id;
+
+	reuse->reuseport_id = id;
+
+	return reuse->reuseport_id;
+}
 
 static struct sock_reuseport *__reuseport_alloc(unsigned int max_socks)
 {
@@ -29,7 +52,7 @@ static struct sock_reuseport *__reuseport_alloc(unsigned int max_socks)
 	return reuse;
 }
 
-int reuseport_alloc(struct sock *sk)
+int reuseport_alloc(struct sock *sk, bool bind_inany)
 {
 	struct sock_reuseport *reuse;
 
@@ -41,9 +64,17 @@ int reuseport_alloc(struct sock *sk)
 	/* Allocation attempts can occur concurrently via the setsockopt path
 	 * and the bind/hash path.  Nothing to do when we lose the race.
 	 */
-	if (rcu_dereference_protected(sk->sk_reuseport_cb,
-				      lockdep_is_held(&reuseport_lock)))
+	reuse = rcu_dereference_protected(sk->sk_reuseport_cb,
+					  lockdep_is_held(&reuseport_lock));
+	if (reuse) {
+		/* Only set reuse->bind_inany if the bind_inany is true.
+		 * Otherwise, it will overwrite the reuse->bind_inany
+		 * which was set by the bind/hash path.
+		 */
+		if (bind_inany)
+			reuse->bind_inany = bind_inany;
 		goto out;
+	}
 
 	reuse = __reuseport_alloc(INIT_SOCKS);
 	if (!reuse) {
@@ -53,6 +84,7 @@ int reuseport_alloc(struct sock *sk)
 
 	reuse->socks[0] = sk;
 	reuse->num_socks = 1;
+	reuse->bind_inany = bind_inany;
 	rcu_assign_pointer(sk->sk_reuseport_cb, reuse);
 
 out:
@@ -78,9 +110,12 @@ static struct sock_reuseport *reuseport_grow(struct sock_reuseport *reuse)
 	more_reuse->max_socks = more_socks_size;
 	more_reuse->num_socks = reuse->num_socks;
 	more_reuse->prog = reuse->prog;
+	more_reuse->reuseport_id = reuse->reuseport_id;
+	more_reuse->bind_inany = reuse->bind_inany;
 
 	memcpy(more_reuse->socks, reuse->socks,
 	       reuse->num_socks * sizeof(struct sock *));
+	more_reuse->synq_overflow_ts = READ_ONCE(reuse->synq_overflow_ts);
 
 	for (i = 0; i < reuse->num_socks; ++i)
 		rcu_assign_pointer(reuse->socks[i]->sk_reuseport_cb,
@@ -99,8 +134,9 @@ static void reuseport_free_rcu(struct rcu_head *head)
 	struct sock_reuseport *reuse;
 
 	reuse = container_of(head, struct sock_reuseport, rcu);
-	if (reuse->prog)
-		bpf_prog_destroy(reuse->prog);
+	sk_reuseport_prog_free(rcu_dereference_protected(reuse->prog, 1));
+	if (reuse->reuseport_id)
+		ida_simple_remove(&reuseport_ida, reuse->reuseport_id);
 	kfree(reuse);
 }
 
@@ -110,12 +146,12 @@ static void reuseport_free_rcu(struct rcu_head *head)
  *  @sk2: Socket belonging to the existing reuseport group.
  *  May return ENOMEM and not add socket to group under memory pressure.
  */
-int reuseport_add_sock(struct sock *sk, struct sock *sk2)
+int reuseport_add_sock(struct sock *sk, struct sock *sk2, bool bind_inany)
 {
 	struct sock_reuseport *old_reuse, *reuse;
 
 	if (!rcu_access_pointer(sk2->sk_reuseport_cb)) {
-		int err = reuseport_alloc(sk2);
+		int err = reuseport_alloc(sk2, bind_inany);
 
 		if (err)
 			return err;
@@ -160,6 +196,14 @@ void reuseport_detach_sock(struct sock *sk)
 	spin_lock_bh(&reuseport_lock);
 	reuse = rcu_dereference_protected(sk->sk_reuseport_cb,
 					  lockdep_is_held(&reuseport_lock));
+
+	/* At least one of the sk in this reuseport group is added to
+	 * a bpf map.  Notify the bpf side.  The bpf map logic will
+	 * remove the sk if it is indeed added to a bpf map.
+	 */
+	if (reuse->reuseport_id)
+		bpf_sk_reuseport_detach(sk);
+
 	rcu_assign_pointer(sk->sk_reuseport_cb, NULL);
 
 	for (i = 0; i < reuse->num_socks; i++) {
@@ -175,9 +219,9 @@ void reuseport_detach_sock(struct sock *sk)
 }
 EXPORT_SYMBOL(reuseport_detach_sock);
 
-static struct sock *run_bpf(struct sock_reuseport *reuse, u16 socks,
-			    struct bpf_prog *prog, struct sk_buff *skb,
-			    int hdr_len)
+static struct sock *run_bpf_filter(struct sock_reuseport *reuse, u16 socks,
+				   struct bpf_prog *prog, struct sk_buff *skb,
+				   int hdr_len)
 {
 	struct sk_buff *nskb = NULL;
 	u32 index;
@@ -238,9 +282,15 @@ struct sock *reuseport_select_sock(struct sock *sk,
 		/* paired with smp_wmb() in reuseport_add_sock() */
 		smp_rmb();
 
-		if (prog && skb)
-			sk2 = run_bpf(reuse, socks, prog, skb, hdr_len);
+		if (!prog || !skb)
+			goto select_by_hash;
+
+		if (prog->type == BPF_PROG_TYPE_SK_REUSEPORT)
+			sk2 = bpf_run_sk_reuseport(reuse, sk, prog, skb, hash);
+		else
+			sk2 = run_bpf_filter(reuse, socks, prog, skb, hdr_len);
 
+select_by_hash:
 		/* no bpf or invalid bpf result: fall back to hash usage */
 		if (!sk2)
 			sk2 = reuse->socks[reciprocal_scale(hash, socks)];
@@ -252,12 +302,21 @@ out:
 }
 EXPORT_SYMBOL(reuseport_select_sock);
 
-struct bpf_prog *
-reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog)
+int reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog)
 {
 	struct sock_reuseport *reuse;
 	struct bpf_prog *old_prog;
 
+	if (sk_unhashed(sk) && sk->sk_reuseport) {
+		int err = reuseport_alloc(sk, false);
+
+		if (err)
+			return err;
+	} else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
+		/* The socket wasn't bound with SO_REUSEPORT */
+		return -EINVAL;
+	}
+
 	spin_lock_bh(&reuseport_lock);
 	reuse = rcu_dereference_protected(sk->sk_reuseport_cb,
 					  lockdep_is_held(&reuseport_lock));
@@ -266,6 +325,7 @@ reuseport_attach_prog(struct sock *sk, struct bpf_prog *prog)
 	rcu_assign_pointer(reuse->prog, prog);
 	spin_unlock_bh(&reuseport_lock);
 
-	return old_prog;
+	sk_reuseport_prog_free(old_prog);
+	return 0;
 }
 EXPORT_SYMBOL(reuseport_attach_prog);
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 33a88e045efd..dfd5009f96ef 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -107,6 +107,15 @@ bool inet_rcv_saddr_equal(const struct sock *sk, const struct sock *sk2,
 }
 EXPORT_SYMBOL(inet_rcv_saddr_equal);
 
+bool inet_rcv_saddr_any(const struct sock *sk)
+{
+#if IS_ENABLED(CONFIG_IPV6)
+	if (sk->sk_family == AF_INET6)
+		return ipv6_addr_any(&sk->sk_v6_rcv_saddr);
+#endif
+	return !sk->sk_rcv_saddr;
+}
+
 void inet_get_local_port_range(struct net *net, int *low, int *high)
 {
 	unsigned int seq;
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 3647167c8fa3..f5c9ef2586de 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -328,7 +328,7 @@ struct sock *__inet_lookup_listener(struct net *net,
 				    saddr, sport, daddr, hnum,
 				    dif, sdif);
 	if (result)
-		return result;
+		goto done;
 
 	/* Lookup lhash2 with INADDR_ANY */
 
@@ -337,9 +337,10 @@ struct sock *__inet_lookup_listener(struct net *net,
 	if (ilb2->count > ilb->count)
 		goto port_lookup;
 
-	return inet_lhash2_lookup(net, ilb2, skb, doff,
-				  saddr, sport, daddr, hnum,
-				  dif, sdif);
+	result = inet_lhash2_lookup(net, ilb2, skb, doff,
+				    saddr, sport, daddr, hnum,
+				    dif, sdif);
+	goto done;
 
 port_lookup:
 	sk_for_each_rcu(sk, &ilb->head) {
@@ -352,12 +353,15 @@ port_lookup:
 				result = reuseport_select_sock(sk, phash,
 							       skb, doff);
 				if (result)
-					return result;
+					goto done;
 			}
 			result = sk;
 			hiscore = score;
 		}
 	}
+done:
+	if (unlikely(IS_ERR(result)))
+		return NULL;
 	return result;
 }
 EXPORT_SYMBOL_GPL(__inet_lookup_listener);
@@ -567,10 +571,11 @@ static int inet_reuseport_add_sock(struct sock *sk,
 		    inet_csk(sk2)->icsk_bind_hash == tb &&
 		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 		    inet_rcv_saddr_equal(sk, sk2, false))
-			return reuseport_add_sock(sk, sk2);
+			return reuseport_add_sock(sk, sk2,
+						  inet_rcv_saddr_any(sk));
 	}
 
-	return reuseport_alloc(sk);
+	return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 }
 
 int __inet_hash(struct sock *sk, struct sock *osk)
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 060e841dde40..f4e35b2ff8b8 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -221,11 +221,12 @@ static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
 		    (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
 		    sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
 		    inet_rcv_saddr_equal(sk, sk2, false)) {
-			return reuseport_add_sock(sk, sk2);
+			return reuseport_add_sock(sk, sk2,
+						  inet_rcv_saddr_any(sk));
 		}
 	}
 
-	return reuseport_alloc(sk);
+	return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
 }
 
 /**
@@ -498,6 +499,8 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
 						  daddr, hnum, dif, sdif,
 						  exact_dif, hslot2, skb);
 		}
+		if (unlikely(IS_ERR(result)))
+			return NULL;
 		return result;
 	}
 begin:
@@ -512,6 +515,8 @@ begin:
 						   saddr, sport);
 				result = reuseport_select_sock(sk, hash, skb,
 							sizeof(struct udphdr));
+				if (unlikely(IS_ERR(result)))
+					return NULL;
 				if (result)
 					return result;
 			}
diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
index 595ad408dba0..3d7c7460a0c5 100644
--- a/net/ipv6/inet6_hashtables.c
+++ b/net/ipv6/inet6_hashtables.c
@@ -191,7 +191,7 @@ struct sock *inet6_lookup_listener(struct net *net,
 				     saddr, sport, daddr, hnum,
 				     dif, sdif);
 	if (result)
-		return result;
+		goto done;
 
 	/* Lookup lhash2 with in6addr_any */
 
@@ -200,9 +200,10 @@ struct sock *inet6_lookup_listener(struct net *net,
 	if (ilb2->count > ilb->count)
 		goto port_lookup;
 
-	return inet6_lhash2_lookup(net, ilb2, skb, doff,
-				   saddr, sport, daddr, hnum,
-				   dif, sdif);
+	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
+				     saddr, sport, daddr, hnum,
+				     dif, sdif);
+	goto done;
 
 port_lookup:
 	sk_for_each(sk, &ilb->head) {
@@ -214,12 +215,15 @@ port_lookup:
 				result = reuseport_select_sock(sk, phash,
 							       skb, doff);
 				if (result)
-					return result;
+					goto done;
 			}
 			result = sk;
 			hiscore = score;
 		}
 	}
+done:
+	if (unlikely(IS_ERR(result)))
+		return NULL;
 	return result;
 }
 EXPORT_SYMBOL_GPL(inet6_lookup_listener);
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index f6b96956a8ed..83f4c77c79d8 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -235,6 +235,8 @@ struct sock *__udp6_lib_lookup(struct net *net,
 						  exact_dif, hslot2,
 						  skb);
 		}
+		if (unlikely(IS_ERR(result)))
+			return NULL;
 		return result;
 	}
 begin:
@@ -249,6 +251,8 @@ begin:
 						    saddr, sport);
 				result = reuseport_select_sock(sk, hash, skb,
 							sizeof(struct udphdr));
+				if (unlikely(IS_ERR(result)))
+					return NULL;
 				if (result)
 					return result;
 			}
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index dd5758dc35d3..3102a2a23c31 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -126,6 +126,7 @@ enum bpf_map_type {
 	BPF_MAP_TYPE_XSKMAP,
 	BPF_MAP_TYPE_SOCKHASH,
 	BPF_MAP_TYPE_CGROUP_STORAGE,
+	BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
 };
 
 enum bpf_prog_type {
@@ -150,6 +151,7 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_CGROUP_SOCK_ADDR,
 	BPF_PROG_TYPE_LWT_SEG6LOCAL,
 	BPF_PROG_TYPE_LIRC_MODE2,
+	BPF_PROG_TYPE_SK_REUSEPORT,
 };
 
 enum bpf_attach_type {
@@ -2113,6 +2115,14 @@ union bpf_attr {
  *		the shared data.
  *	Return
  *		Pointer to the local storage area.
+ *
+ * int bpf_sk_select_reuseport(struct sk_reuseport_md *reuse, struct bpf_map *map, void *key, u64 flags)
+ *	Description
+ *		Select a SO_REUSEPORT sk from a	BPF_MAP_TYPE_REUSEPORT_ARRAY map
+ *		It checks the selected sk is matching the incoming
+ *		request in the skb.
+ *	Return
+ *		0 on success, or a negative error in case of failure.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -2196,7 +2206,8 @@ union bpf_attr {
 	FN(rc_keydown),			\
 	FN(skb_cgroup_id),		\
 	FN(get_current_cgroup_id),	\
-	FN(get_local_storage),
+	FN(get_local_storage),		\
+	FN(sk_select_reuseport),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
@@ -2413,6 +2424,30 @@ struct sk_msg_md {
 	__u32 local_port;	/* stored in host byte order */
 };
 
+struct sk_reuseport_md {
+	/*
+	 * Start of directly accessible data. It begins from
+	 * the tcp/udp header.
+	 */
+	void *data;
+	void *data_end;		/* End of directly accessible data */
+	/*
+	 * Total length of packet (starting from the tcp/udp header).
+	 * Note that the directly accessible bytes (data_end - data)
+	 * could be less than this "len".  Those bytes could be
+	 * indirectly read by a helper "bpf_skb_load_bytes()".
+	 */
+	__u32 len;
+	/*
+	 * Eth protocol in the mac header (network byte order). e.g.
+	 * ETH_P_IP(0x0800) and ETH_P_IPV6(0x86DD)
+	 */
+	__u32 eth_protocol;
+	__u32 ip_protocol;	/* IP protocol. e.g. IPPROTO_TCP, IPPROTO_UDP */
+	__u32 bind_inany;	/* Is sock bound to an INANY address? */
+	__u32 hash;		/* A hash of the packet 4 tuples */
+};
+
 #define BPF_TAG_SIZE	8
 
 struct bpf_prog_info {
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 9ddc89dae962..60aa4ca8b2c5 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -92,6 +92,7 @@ int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr)
 	attr.btf_key_type_id = create_attr->btf_key_type_id;
 	attr.btf_value_type_id = create_attr->btf_value_type_id;
 	attr.map_ifindex = create_attr->map_ifindex;
+	attr.inner_map_fd = create_attr->inner_map_fd;
 
 	return sys_bpf(BPF_MAP_CREATE, &attr, sizeof(attr));
 }
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 0639a30a457d..6f38164b2618 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -39,6 +39,7 @@ struct bpf_create_map_attr {
 	__u32 btf_key_type_id;
 	__u32 btf_value_type_id;
 	__u32 map_ifindex;
+	__u32 inner_map_fd;
 };
 
 int bpf_create_map_xattr(const struct bpf_create_map_attr *create_attr);
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 40211b51427a..2abd0f112627 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -1501,6 +1501,7 @@ static bool bpf_prog_type__needs_kver(enum bpf_prog_type type)
 	case BPF_PROG_TYPE_SK_MSG:
 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
 	case BPF_PROG_TYPE_LIRC_MODE2:
+	case BPF_PROG_TYPE_SK_REUSEPORT:
 		return false;
 	case BPF_PROG_TYPE_UNSPEC:
 	case BPF_PROG_TYPE_KPROBE:
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 17a7a5818ee1..daed162043c2 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -23,7 +23,7 @@ $(TEST_CUSTOM_PROGS): $(OUTPUT)/%: %.c
 TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test_progs \
 	test_align test_verifier_log test_dev_cgroup test_tcpbpf_user \
 	test_sock test_btf test_sockmap test_lirc_mode2_user get_cgroup_id_user \
-	test_socket_cookie test_cgroup_storage
+	test_socket_cookie test_cgroup_storage test_select_reuseport
 
 TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test_obj_id.o \
 	test_pkt_md_access.o test_xdp_redirect.o test_xdp_meta.o sockmap_parse_prog.o     \
@@ -34,7 +34,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
 	test_btf_haskv.o test_btf_nokv.o test_sockmap_kern.o test_tunnel_kern.o \
 	test_get_stack_rawtp.o test_sockmap_kern.o test_sockhash_kern.o \
 	test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
-	get_cgroup_id_kern.o socket_cookie_prog.o
+	get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o
 
 # Order correspond to 'make run_tests' order
 TEST_PROGS := test_kmod.sh \
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index 9ba1c72d7cf5..5c32266c2c38 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -111,6 +111,8 @@ static int (*bpf_xdp_adjust_tail)(void *ctx, int offset) =
 static int (*bpf_skb_get_xfrm_state)(void *ctx, int index, void *state,
 				     int size, int flags) =
 	(void *) BPF_FUNC_skb_get_xfrm_state;
+static int (*bpf_sk_select_reuseport)(void *ctx, void *map, void *key, __u32 flags) =
+	(void *) BPF_FUNC_sk_select_reuseport;
 static int (*bpf_get_stack)(void *ctx, void *buf, int size, int flags) =
 	(void *) BPF_FUNC_get_stack;
 static int (*bpf_fib_lookup)(void *ctx, struct bpf_fib_lookup *params,
@@ -173,6 +175,8 @@ struct bpf_map_def {
 
 static int (*bpf_skb_load_bytes)(void *ctx, int off, void *to, int len) =
 	(void *) BPF_FUNC_skb_load_bytes;
+static int (*bpf_skb_load_bytes_relative)(void *ctx, int off, void *to, int len, __u32 start_header) =
+	(void *) BPF_FUNC_skb_load_bytes_relative;
 static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
 	(void *) BPF_FUNC_skb_store_bytes;
 static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flags) =
diff --git a/tools/testing/selftests/bpf/bpf_util.h b/tools/testing/selftests/bpf/bpf_util.h
index d0811b3d6a6f..315a44fa32af 100644
--- a/tools/testing/selftests/bpf/bpf_util.h
+++ b/tools/testing/selftests/bpf/bpf_util.h
@@ -44,4 +44,8 @@ static inline unsigned int bpf_num_possible_cpus(void)
 		name[bpf_num_possible_cpus()]
 #define bpf_percpu(name, cpu) name[(cpu)].v
 
+#ifndef ARRAY_SIZE
+# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#endif
+
 #endif /* __BPF_UTIL__ */
diff --git a/tools/testing/selftests/bpf/test_align.c b/tools/testing/selftests/bpf/test_align.c
index 6b1b302310fe..5f377ec53f2f 100644
--- a/tools/testing/selftests/bpf/test_align.c
+++ b/tools/testing/selftests/bpf/test_align.c
@@ -18,10 +18,7 @@
 
 #include "../../../include/linux/filter.h"
 #include "bpf_rlimit.h"
-
-#ifndef ARRAY_SIZE
-# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-#endif
+#include "bpf_util.h"
 
 #define MAX_INSNS	512
 #define MAX_MATCHES	16
diff --git a/tools/testing/selftests/bpf/test_btf.c b/tools/testing/selftests/bpf/test_btf.c
index 7fa8c800c540..6b5cfeb7a9cc 100644
--- a/tools/testing/selftests/bpf/test_btf.c
+++ b/tools/testing/selftests/bpf/test_btf.c
@@ -19,6 +19,7 @@
 #include <bpf/btf.h>
 
 #include "bpf_rlimit.h"
+#include "bpf_util.h"
 
 static uint32_t pass_cnt;
 static uint32_t error_cnt;
@@ -93,10 +94,6 @@ static int __base_pr(const char *format, ...)
 #define MAX_NR_RAW_TYPES 1024
 #define BTF_LOG_BUF_SIZE 65535
 
-#ifndef ARRAY_SIZE
-# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-#endif
-
 static struct args {
 	unsigned int raw_test_num;
 	unsigned int file_test_num;
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index 6c253343a6f9..4b7c74f5faa7 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -17,7 +17,8 @@
 #include <stdlib.h>
 
 #include <sys/wait.h>
-
+#include <sys/socket.h>
+#include <netinet/in.h>
 #include <linux/bpf.h>
 
 #include <bpf/bpf.h>
@@ -26,8 +27,21 @@
 #include "bpf_util.h"
 #include "bpf_rlimit.h"
 
+#ifndef ENOTSUPP
+#define ENOTSUPP 524
+#endif
+
 static int map_flags;
 
+#define CHECK(condition, tag, format...) ({				\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		printf("%s(%d):FAIL:%s ", __func__, __LINE__, tag);	\
+		printf(format);						\
+		exit(-1);						\
+	}								\
+})
+
 static void test_hashmap(int task, void *data)
 {
 	long long key, next_key, first_key, value;
@@ -1150,6 +1164,250 @@ static void test_map_wronly(void)
 	assert(bpf_map_get_next_key(fd, &key, &value) == -1 && errno == EPERM);
 }
 
+static void prepare_reuseport_grp(int type, int map_fd,
+				  __s64 *fds64, __u64 *sk_cookies,
+				  unsigned int n)
+{
+	socklen_t optlen, addrlen;
+	struct sockaddr_in6 s6;
+	const __u32 index0 = 0;
+	const int optval = 1;
+	unsigned int i;
+	u64 sk_cookie;
+	__s64 fd64;
+	int err;
+
+	s6.sin6_family = AF_INET6;
+	s6.sin6_addr = in6addr_any;
+	s6.sin6_port = 0;
+	addrlen = sizeof(s6);
+	optlen = sizeof(sk_cookie);
+
+	for (i = 0; i < n; i++) {
+		fd64 = socket(AF_INET6, type, 0);
+		CHECK(fd64 == -1, "socket()",
+		      "sock_type:%d fd64:%lld errno:%d\n",
+		      type, fd64, errno);
+
+		err = setsockopt(fd64, SOL_SOCKET, SO_REUSEPORT,
+				 &optval, sizeof(optval));
+		CHECK(err == -1, "setsockopt(SO_REUSEEPORT)",
+		      "err:%d errno:%d\n", err, errno);
+
+		/* reuseport_array does not allow unbound sk */
+		err = bpf_map_update_elem(map_fd, &index0, &fd64,
+					  BPF_ANY);
+		CHECK(err != -1 || errno != EINVAL,
+		      "reuseport array update unbound sk",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		err = bind(fd64, (struct sockaddr *)&s6, sizeof(s6));
+		CHECK(err == -1, "bind()",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		if (i == 0) {
+			err = getsockname(fd64, (struct sockaddr *)&s6,
+					  &addrlen);
+			CHECK(err == -1, "getsockname()",
+			      "sock_type:%d err:%d errno:%d\n",
+			      type, err, errno);
+		}
+
+		err = getsockopt(fd64, SOL_SOCKET, SO_COOKIE, &sk_cookie,
+				 &optlen);
+		CHECK(err == -1, "getsockopt(SO_COOKIE)",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		if (type == SOCK_STREAM) {
+			/*
+			 * reuseport_array does not allow
+			 * non-listening tcp sk.
+			 */
+			err = bpf_map_update_elem(map_fd, &index0, &fd64,
+						  BPF_ANY);
+			CHECK(err != -1 || errno != EINVAL,
+			      "reuseport array update non-listening sk",
+			      "sock_type:%d err:%d errno:%d\n",
+			      type, err, errno);
+			err = listen(fd64, 0);
+			CHECK(err == -1, "listen()",
+			      "sock_type:%d, err:%d errno:%d\n",
+			      type, err, errno);
+		}
+
+		fds64[i] = fd64;
+		sk_cookies[i] = sk_cookie;
+	}
+}
+
+static void test_reuseport_array(void)
+{
+#define REUSEPORT_FD_IDX(err, last) ({ (err) ? last : !last; })
+
+	const __u32 array_size = 4, index0 = 0, index3 = 3;
+	int types[2] = { SOCK_STREAM, SOCK_DGRAM }, type;
+	__u64 grpa_cookies[2], sk_cookie, map_cookie;
+	__s64 grpa_fds64[2] = { -1, -1 }, fd64 = -1;
+	const __u32 bad_index = array_size;
+	int map_fd, err, t, f;
+	__u32 fds_idx = 0;
+	int fd;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
+				sizeof(__u32), sizeof(__u64), array_size, 0);
+	CHECK(map_fd == -1, "reuseport array create",
+	      "map_fd:%d, errno:%d\n", map_fd, errno);
+
+	/* Test lookup/update/delete with invalid index */
+	err = bpf_map_delete_elem(map_fd, &bad_index);
+	CHECK(err != -1 || errno != E2BIG, "reuseport array del >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	err = bpf_map_update_elem(map_fd, &bad_index, &fd64, BPF_ANY);
+	CHECK(err != -1 || errno != E2BIG,
+	      "reuseport array update >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	err = bpf_map_lookup_elem(map_fd, &bad_index, &map_cookie);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array update >=max_entries",
+	      "err:%d errno:%d\n", err, errno);
+
+	/* Test lookup/delete non existence elem */
+	err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array lookup not-exist elem",
+	      "err:%d errno:%d\n", err, errno);
+	err = bpf_map_delete_elem(map_fd, &index3);
+	CHECK(err != -1 || errno != ENOENT,
+	      "reuseport array del not-exist elem",
+	      "err:%d errno:%d\n", err, errno);
+
+	for (t = 0; t < ARRAY_SIZE(types); t++) {
+		type = types[t];
+
+		prepare_reuseport_grp(type, map_fd, grpa_fds64,
+				      grpa_cookies, ARRAY_SIZE(grpa_fds64));
+
+		/* Test BPF_* update flags */
+		/* BPF_EXIST failure case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_EXIST);
+		CHECK(err != -1 || errno != ENOENT,
+		      "reuseport array update empty elem BPF_EXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_NOEXIST success case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_NOEXIST);
+		CHECK(err == -1,
+		      "reuseport array update empty elem BPF_NOEXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_EXIST success case. */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_EXIST);
+		CHECK(err == -1,
+		      "reuseport array update same elem BPF_EXIST",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_NOEXIST failure case */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_NOEXIST);
+		CHECK(err != -1 || errno != EEXIST,
+		      "reuseport array update non-empty elem BPF_NOEXIST",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+		fds_idx = REUSEPORT_FD_IDX(err, fds_idx);
+
+		/* BPF_ANY case (always succeed) */
+		err = bpf_map_update_elem(map_fd, &index3, &grpa_fds64[fds_idx],
+					  BPF_ANY);
+		CHECK(err == -1,
+		      "reuseport array update same sk with BPF_ANY",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		fd64 = grpa_fds64[fds_idx];
+		sk_cookie = grpa_cookies[fds_idx];
+
+		/* The same sk cannot be added to reuseport_array twice */
+		err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_ANY);
+		CHECK(err != -1 || errno != EBUSY,
+		      "reuseport array update same sk with same index",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		err = bpf_map_update_elem(map_fd, &index0, &fd64, BPF_ANY);
+		CHECK(err != -1 || errno != EBUSY,
+		      "reuseport array update same sk with different index",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		/* Test delete elem */
+		err = bpf_map_delete_elem(map_fd, &index3);
+		CHECK(err == -1, "reuseport array delete sk",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+
+		/* Add it back with BPF_NOEXIST */
+		err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_NOEXIST);
+		CHECK(err == -1,
+		      "reuseport array re-add with BPF_NOEXIST after del",
+		      "sock_type:%d err:%d errno:%d\n", type, err, errno);
+
+		/* Test cookie */
+		err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+		CHECK(err == -1 || sk_cookie != map_cookie,
+		      "reuseport array lookup re-added sk",
+		      "sock_type:%d err:%d errno:%d sk_cookie:0x%llx map_cookie:0x%llxn",
+		      type, err, errno, sk_cookie, map_cookie);
+
+		/* Test elem removed by close() */
+		for (f = 0; f < ARRAY_SIZE(grpa_fds64); f++)
+			close(grpa_fds64[f]);
+		err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+		CHECK(err != -1 || errno != ENOENT,
+		      "reuseport array lookup after close()",
+		      "sock_type:%d err:%d errno:%d\n",
+		      type, err, errno);
+	}
+
+	/* Test SOCK_RAW */
+	fd64 = socket(AF_INET6, SOCK_RAW, IPPROTO_UDP);
+	CHECK(fd64 == -1, "socket(SOCK_RAW)", "err:%d errno:%d\n",
+	      err, errno);
+	err = bpf_map_update_elem(map_fd, &index3, &fd64, BPF_NOEXIST);
+	CHECK(err != -1 || errno != ENOTSUPP, "reuseport array update SOCK_RAW",
+	      "err:%d errno:%d\n", err, errno);
+	close(fd64);
+
+	/* Close the 64 bit value map */
+	close(map_fd);
+
+	/* Test 32 bit fd */
+	map_fd = bpf_create_map(BPF_MAP_TYPE_REUSEPORT_SOCKARRAY,
+				sizeof(__u32), sizeof(__u32), array_size, 0);
+	CHECK(map_fd == -1, "reuseport array create",
+	      "map_fd:%d, errno:%d\n", map_fd, errno);
+	prepare_reuseport_grp(SOCK_STREAM, map_fd, &fd64, &sk_cookie, 1);
+	fd = fd64;
+	err = bpf_map_update_elem(map_fd, &index3, &fd, BPF_NOEXIST);
+	CHECK(err == -1, "reuseport array update 32 bit fd",
+	      "err:%d errno:%d\n", err, errno);
+	err = bpf_map_lookup_elem(map_fd, &index3, &map_cookie);
+	CHECK(err != -1 || errno != ENOSPC,
+	      "reuseport array lookup 32 bit fd",
+	      "err:%d errno:%d\n", err, errno);
+	close(fd);
+	close(map_fd);
+}
+
 static void run_all_tests(void)
 {
 	test_hashmap(0, NULL);
@@ -1170,6 +1428,8 @@ static void run_all_tests(void)
 
 	test_map_rdonly();
 	test_map_wronly();
+
+	test_reuseport_array();
 }
 
 int main(void)
diff --git a/tools/testing/selftests/bpf/test_select_reuseport.c b/tools/testing/selftests/bpf/test_select_reuseport.c
new file mode 100644
index 000000000000..75646d9b34aa
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_select_reuseport.c
@@ -0,0 +1,688 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2018 Facebook */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <string.h>
+#include <errno.h>
+#include <assert.h>
+#include <fcntl.h>
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/if_ether.h>
+#include <sys/types.h>
+#include <sys/epoll.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+#include "bpf_rlimit.h"
+#include "bpf_util.h"
+#include "test_select_reuseport_common.h"
+
+#define MIN_TCPHDR_LEN 20
+#define UDPHDR_LEN 8
+
+#define TCP_SYNCOOKIE_SYSCTL "/proc/sys/net/ipv4/tcp_syncookies"
+#define TCP_FO_SYSCTL "/proc/sys/net/ipv4/tcp_fastopen"
+#define REUSEPORT_ARRAY_SIZE 32
+
+static int result_map, tmp_index_ovr_map, linum_map, data_check_map;
+static enum result expected_results[NR_RESULTS];
+static int sk_fds[REUSEPORT_ARRAY_SIZE];
+static int reuseport_array, outer_map;
+static int select_by_skb_data_prog;
+static int saved_tcp_syncookie;
+static struct bpf_object *obj;
+static int saved_tcp_fo;
+static __u32 index_zero;
+static int epfd;
+
+static union sa46 {
+	struct sockaddr_in6 v6;
+	struct sockaddr_in v4;
+	sa_family_t family;
+} srv_sa;
+
+#define CHECK(condition, tag, format...) ({				\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		printf("%s(%d):FAIL:%s ", __func__, __LINE__, tag);	\
+		printf(format);						\
+		exit(-1);						\
+	}								\
+})
+
+static void create_maps(void)
+{
+	struct bpf_create_map_attr attr = {};
+
+	/* Creating reuseport_array */
+	attr.name = "reuseport_array";
+	attr.map_type = BPF_MAP_TYPE_REUSEPORT_SOCKARRAY;
+	attr.key_size = sizeof(__u32);
+	attr.value_size = sizeof(__u32);
+	attr.max_entries = REUSEPORT_ARRAY_SIZE;
+
+	reuseport_array = bpf_create_map_xattr(&attr);
+	CHECK(reuseport_array == -1, "creating reuseport_array",
+	      "reuseport_array:%d errno:%d\n", reuseport_array, errno);
+
+	/* Creating outer_map */
+	attr.name = "outer_map";
+	attr.map_type = BPF_MAP_TYPE_ARRAY_OF_MAPS;
+	attr.key_size = sizeof(__u32);
+	attr.value_size = sizeof(__u32);
+	attr.max_entries = 1;
+	attr.inner_map_fd = reuseport_array;
+	outer_map = bpf_create_map_xattr(&attr);
+	CHECK(outer_map == -1, "creating outer_map",
+	      "outer_map:%d errno:%d\n", outer_map, errno);
+}
+
+static void prepare_bpf_obj(void)
+{
+	struct bpf_program *prog;
+	struct bpf_map *map;
+	int err;
+	struct bpf_object_open_attr attr = {
+		.file = "test_select_reuseport_kern.o",
+		.prog_type = BPF_PROG_TYPE_SK_REUSEPORT,
+	};
+
+	obj = bpf_object__open_xattr(&attr);
+	CHECK(IS_ERR_OR_NULL(obj), "open test_select_reuseport_kern.o",
+	      "obj:%p PTR_ERR(obj):%ld\n", obj, PTR_ERR(obj));
+
+	prog = bpf_program__next(NULL, obj);
+	CHECK(!prog, "get first bpf_program", "!prog\n");
+	bpf_program__set_type(prog, attr.prog_type);
+
+	map = bpf_object__find_map_by_name(obj, "outer_map");
+	CHECK(!map, "find outer_map", "!map\n");
+	err = bpf_map__reuse_fd(map, outer_map);
+	CHECK(err, "reuse outer_map", "err:%d\n", err);
+
+	err = bpf_object__load(obj);
+	CHECK(err, "load bpf_object", "err:%d\n", err);
+
+	select_by_skb_data_prog = bpf_program__fd(prog);
+	CHECK(select_by_skb_data_prog == -1, "get prog fd",
+	      "select_by_skb_data_prog:%d\n", select_by_skb_data_prog);
+
+	map = bpf_object__find_map_by_name(obj, "result_map");
+	CHECK(!map, "find result_map", "!map\n");
+	result_map = bpf_map__fd(map);
+	CHECK(result_map == -1, "get result_map fd",
+	      "result_map:%d\n", result_map);
+
+	map = bpf_object__find_map_by_name(obj, "tmp_index_ovr_map");
+	CHECK(!map, "find tmp_index_ovr_map", "!map\n");
+	tmp_index_ovr_map = bpf_map__fd(map);
+	CHECK(tmp_index_ovr_map == -1, "get tmp_index_ovr_map fd",
+	      "tmp_index_ovr_map:%d\n", tmp_index_ovr_map);
+
+	map = bpf_object__find_map_by_name(obj, "linum_map");
+	CHECK(!map, "find linum_map", "!map\n");
+	linum_map = bpf_map__fd(map);
+	CHECK(linum_map == -1, "get linum_map fd",
+	      "linum_map:%d\n", linum_map);
+
+	map = bpf_object__find_map_by_name(obj, "data_check_map");
+	CHECK(!map, "find data_check_map", "!map\n");
+	data_check_map = bpf_map__fd(map);
+	CHECK(data_check_map == -1, "get data_check_map fd",
+	      "data_check_map:%d\n", data_check_map);
+}
+
+static void sa46_init_loopback(union sa46 *sa, sa_family_t family)
+{
+	memset(sa, 0, sizeof(*sa));
+	sa->family = family;
+	if (sa->family == AF_INET6)
+		sa->v6.sin6_addr = in6addr_loopback;
+	else
+		sa->v4.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+}
+
+static void sa46_init_inany(union sa46 *sa, sa_family_t family)
+{
+	memset(sa, 0, sizeof(*sa));
+	sa->family = family;
+	if (sa->family == AF_INET6)
+		sa->v6.sin6_addr = in6addr_any;
+	else
+		sa->v4.sin_addr.s_addr = INADDR_ANY;
+}
+
+static int read_int_sysctl(const char *sysctl)
+{
+	char buf[16];
+	int fd, ret;
+
+	fd = open(sysctl, 0);
+	CHECK(fd == -1, "open(sysctl)", "sysctl:%s fd:%d errno:%d\n",
+	      sysctl, fd, errno);
+
+	ret = read(fd, buf, sizeof(buf));
+	CHECK(ret <= 0, "read(sysctl)", "sysctl:%s ret:%d errno:%d\n",
+	      sysctl, ret, errno);
+	close(fd);
+
+	return atoi(buf);
+}
+
+static void write_int_sysctl(const char *sysctl, int v)
+{
+	int fd, ret, size;
+	char buf[16];
+
+	fd = open(sysctl, O_RDWR);
+	CHECK(fd == -1, "open(sysctl)", "sysctl:%s fd:%d errno:%d\n",
+	      sysctl, fd, errno);
+
+	size = snprintf(buf, sizeof(buf), "%d", v);
+	ret = write(fd, buf, size);
+	CHECK(ret != size, "write(sysctl)",
+	      "sysctl:%s ret:%d size:%d errno:%d\n", sysctl, ret, size, errno);
+	close(fd);
+}
+
+static void restore_sysctls(void)
+{
+	write_int_sysctl(TCP_FO_SYSCTL, saved_tcp_fo);
+	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, saved_tcp_syncookie);
+}
+
+static void enable_fastopen(void)
+{
+	int fo;
+
+	fo = read_int_sysctl(TCP_FO_SYSCTL);
+	write_int_sysctl(TCP_FO_SYSCTL, fo | 7);
+}
+
+static void enable_syncookie(void)
+{
+	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 2);
+}
+
+static void disable_syncookie(void)
+{
+	write_int_sysctl(TCP_SYNCOOKIE_SYSCTL, 0);
+}
+
+static __u32 get_linum(void)
+{
+	__u32 linum;
+	int err;
+
+	err = bpf_map_lookup_elem(linum_map, &index_zero, &linum);
+	CHECK(err == -1, "lookup_elem(linum_map)", "err:%d errno:%d\n",
+	      err, errno);
+
+	return linum;
+}
+
+static void check_data(int type, sa_family_t family, const struct cmd *cmd,
+		       int cli_fd)
+{
+	struct data_check expected = {}, result;
+	union sa46 cli_sa;
+	socklen_t addrlen;
+	int err;
+
+	addrlen = sizeof(cli_sa);
+	err = getsockname(cli_fd, (struct sockaddr *)&cli_sa,
+			  &addrlen);
+	CHECK(err == -1, "getsockname(cli_fd)", "err:%d errno:%d\n",
+	      err, errno);
+
+	err = bpf_map_lookup_elem(data_check_map, &index_zero, &result);
+	CHECK(err == -1, "lookup_elem(data_check_map)", "err:%d errno:%d\n",
+	      err, errno);
+
+	if (type == SOCK_STREAM) {
+		expected.len = MIN_TCPHDR_LEN;
+		expected.ip_protocol = IPPROTO_TCP;
+	} else {
+		expected.len = UDPHDR_LEN;
+		expected.ip_protocol = IPPROTO_UDP;
+	}
+
+	if (family == AF_INET6) {
+		expected.eth_protocol = htons(ETH_P_IPV6);
+		expected.bind_inany = !srv_sa.v6.sin6_addr.s6_addr32[3] &&
+			!srv_sa.v6.sin6_addr.s6_addr32[2] &&
+			!srv_sa.v6.sin6_addr.s6_addr32[1] &&
+			!srv_sa.v6.sin6_addr.s6_addr32[0];
+
+		memcpy(&expected.skb_addrs[0], cli_sa.v6.sin6_addr.s6_addr32,
+		       sizeof(cli_sa.v6.sin6_addr));
+		memcpy(&expected.skb_addrs[4], &in6addr_loopback,
+		       sizeof(in6addr_loopback));
+		expected.skb_ports[0] = cli_sa.v6.sin6_port;
+		expected.skb_ports[1] = srv_sa.v6.sin6_port;
+	} else {
+		expected.eth_protocol = htons(ETH_P_IP);
+		expected.bind_inany = !srv_sa.v4.sin_addr.s_addr;
+
+		expected.skb_addrs[0] = cli_sa.v4.sin_addr.s_addr;
+		expected.skb_addrs[1] = htonl(INADDR_LOOPBACK);
+		expected.skb_ports[0] = cli_sa.v4.sin_port;
+		expected.skb_ports[1] = srv_sa.v4.sin_port;
+	}
+
+	if (memcmp(&result, &expected, offsetof(struct data_check,
+						equal_check_end))) {
+		printf("unexpected data_check\n");
+		printf("  result: (0x%x, %u, %u)\n",
+		       result.eth_protocol, result.ip_protocol,
+		       result.bind_inany);
+		printf("expected: (0x%x, %u, %u)\n",
+		       expected.eth_protocol, expected.ip_protocol,
+		       expected.bind_inany);
+		CHECK(1, "data_check result != expected",
+		      "bpf_prog_linum:%u\n", get_linum());
+	}
+
+	CHECK(!result.hash, "data_check result.hash empty",
+	      "result.hash:%u", result.hash);
+
+	expected.len += cmd ? sizeof(*cmd) : 0;
+	if (type == SOCK_STREAM)
+		CHECK(expected.len > result.len, "expected.len > result.len",
+		      "expected.len:%u result.len:%u bpf_prog_linum:%u\n",
+		      expected.len, result.len, get_linum());
+	else
+		CHECK(expected.len != result.len, "expected.len != result.len",
+		      "expected.len:%u result.len:%u bpf_prog_linum:%u\n",
+		      expected.len, result.len, get_linum());
+}
+
+static void check_results(void)
+{
+	__u32 results[NR_RESULTS];
+	__u32 i, broken = 0;
+	int err;
+
+	for (i = 0; i < NR_RESULTS; i++) {
+		err = bpf_map_lookup_elem(result_map, &i, &results[i]);
+		CHECK(err == -1, "lookup_elem(result_map)",
+		      "i:%u err:%d errno:%d\n", i, err, errno);
+	}
+
+	for (i = 0; i < NR_RESULTS; i++) {
+		if (results[i] != expected_results[i]) {
+			broken = i;
+			break;
+		}
+	}
+
+	if (i == NR_RESULTS)
+		return;
+
+	printf("unexpected result\n");
+	printf(" result: [");
+	printf("%u", results[0]);
+	for (i = 1; i < NR_RESULTS; i++)
+		printf(", %u", results[i]);
+	printf("]\n");
+
+	printf("expected: [");
+	printf("%u", expected_results[0]);
+	for (i = 1; i < NR_RESULTS; i++)
+		printf(", %u", expected_results[i]);
+	printf("]\n");
+
+	CHECK(expected_results[broken] != results[broken],
+	      "unexpected result",
+	      "expected_results[%u] != results[%u] bpf_prog_linum:%u\n",
+	      broken, broken, get_linum());
+}
+
+static int send_data(int type, sa_family_t family, void *data, size_t len,
+		     enum result expected)
+{
+	union sa46 cli_sa;
+	int fd, err;
+
+	fd = socket(family, type, 0);
+	CHECK(fd == -1, "socket()", "fd:%d errno:%d\n", fd, errno);
+
+	sa46_init_loopback(&cli_sa, family);
+	err = bind(fd, (struct sockaddr *)&cli_sa, sizeof(cli_sa));
+	CHECK(fd == -1, "bind(cli_sa)", "err:%d errno:%d\n", err, errno);
+
+	err = sendto(fd, data, len, MSG_FASTOPEN, (struct sockaddr *)&srv_sa,
+		     sizeof(srv_sa));
+	CHECK(err != len && expected >= PASS,
+	      "sendto()", "family:%u err:%d errno:%d expected:%d\n",
+	      family, err, errno, expected);
+
+	return fd;
+}
+
+static void do_test(int type, sa_family_t family, struct cmd *cmd,
+		    enum result expected)
+{
+	int nev, srv_fd, cli_fd;
+	struct epoll_event ev;
+	struct cmd rcv_cmd;
+	ssize_t nread;
+
+	cli_fd = send_data(type, family, cmd, cmd ? sizeof(*cmd) : 0,
+			   expected);
+	nev = epoll_wait(epfd, &ev, 1, expected >= PASS ? 5 : 0);
+	CHECK((nev <= 0 && expected >= PASS) ||
+	      (nev > 0 && expected < PASS),
+	      "nev <> expected",
+	      "nev:%d expected:%d type:%d family:%d data:(%d, %d)\n",
+	      nev, expected, type, family,
+	      cmd ? cmd->reuseport_index : -1,
+	      cmd ? cmd->pass_on_failure : -1);
+	check_results();
+	check_data(type, family, cmd, cli_fd);
+
+	if (expected < PASS)
+		return;
+
+	CHECK(expected != PASS_ERR_SK_SELECT_REUSEPORT &&
+	      cmd->reuseport_index != ev.data.u32,
+	      "check cmd->reuseport_index",
+	      "cmd:(%u, %u) ev.data.u32:%u\n",
+	      cmd->pass_on_failure, cmd->reuseport_index, ev.data.u32);
+
+	srv_fd = sk_fds[ev.data.u32];
+	if (type == SOCK_STREAM) {
+		int new_fd = accept(srv_fd, NULL, 0);
+
+		CHECK(new_fd == -1, "accept(srv_fd)",
+		      "ev.data.u32:%u new_fd:%d errno:%d\n",
+		      ev.data.u32, new_fd, errno);
+
+		nread = recv(new_fd, &rcv_cmd, sizeof(rcv_cmd), MSG_DONTWAIT);
+		CHECK(nread != sizeof(rcv_cmd),
+		      "recv(new_fd)",
+		      "ev.data.u32:%u nread:%zd sizeof(rcv_cmd):%zu errno:%d\n",
+		      ev.data.u32, nread, sizeof(rcv_cmd), errno);
+
+		close(new_fd);
+	} else {
+		nread = recv(srv_fd, &rcv_cmd, sizeof(rcv_cmd), MSG_DONTWAIT);
+		CHECK(nread != sizeof(rcv_cmd),
+		      "recv(sk_fds)",
+		      "ev.data.u32:%u nread:%zd sizeof(rcv_cmd):%zu errno:%d\n",
+		      ev.data.u32, nread, sizeof(rcv_cmd), errno);
+	}
+
+	close(cli_fd);
+}
+
+static void test_err_inner_map(int type, sa_family_t family)
+{
+	struct cmd cmd = {
+		.reuseport_index = 0,
+		.pass_on_failure = 0,
+	};
+
+	printf("%s: ", __func__);
+	expected_results[DROP_ERR_INNER_MAP]++;
+	do_test(type, family, &cmd, DROP_ERR_INNER_MAP);
+	printf("OK\n");
+}
+
+static void test_err_skb_data(int type, sa_family_t family)
+{
+	printf("%s: ", __func__);
+	expected_results[DROP_ERR_SKB_DATA]++;
+	do_test(type, family, NULL, DROP_ERR_SKB_DATA);
+	printf("OK\n");
+}
+
+static void test_err_sk_select_port(int type, sa_family_t family)
+{
+	struct cmd cmd = {
+		.reuseport_index = REUSEPORT_ARRAY_SIZE,
+		.pass_on_failure = 0,
+	};
+
+	printf("%s: ", __func__);
+	expected_results[DROP_ERR_SK_SELECT_REUSEPORT]++;
+	do_test(type, family, &cmd, DROP_ERR_SK_SELECT_REUSEPORT);
+	printf("OK\n");
+}
+
+static void test_pass(int type, sa_family_t family)
+{
+	struct cmd cmd;
+	int i;
+
+	printf("%s: ", __func__);
+	cmd.pass_on_failure = 0;
+	for (i = 0; i < REUSEPORT_ARRAY_SIZE; i++) {
+		expected_results[PASS]++;
+		cmd.reuseport_index = i;
+		do_test(type, family, &cmd, PASS);
+	}
+	printf("OK\n");
+}
+
+static void test_syncookie(int type, sa_family_t family)
+{
+	int err, tmp_index = 1;
+	struct cmd cmd = {
+		.reuseport_index = 0,
+		.pass_on_failure = 0,
+	};
+
+	if (type != SOCK_STREAM)
+		return;
+
+	printf("%s: ", __func__);
+	/*
+	 * +1 for TCP-SYN and
+	 * +1 for the TCP-ACK (ack the syncookie)
+	 */
+	expected_results[PASS] += 2;
+	enable_syncookie();
+	/*
+	 * Simulate TCP-SYN and TCP-ACK are handled by two different sk:
+	 * TCP-SYN: select sk_fds[tmp_index = 1] tmp_index is from the
+	 *          tmp_index_ovr_map
+	 * TCP-ACK: select sk_fds[reuseport_index = 0] reuseport_index
+	 *          is from the cmd.reuseport_index
+	 */
+	err = bpf_map_update_elem(tmp_index_ovr_map, &index_zero,
+				  &tmp_index, BPF_ANY);
+	CHECK(err == -1, "update_elem(tmp_index_ovr_map, 0, 1)",
+	      "err:%d errno:%d\n", err, errno);
+	do_test(type, family, &cmd, PASS);
+	err = bpf_map_lookup_elem(tmp_index_ovr_map, &index_zero,
+				  &tmp_index);
+	CHECK(err == -1 || tmp_index != -1,
+	      "lookup_elem(tmp_index_ovr_map)",
+	      "err:%d errno:%d tmp_index:%d\n",
+	      err, errno, tmp_index);
+	disable_syncookie();
+	printf("OK\n");
+}
+
+static void test_pass_on_err(int type, sa_family_t family)
+{
+	struct cmd cmd = {
+		.reuseport_index = REUSEPORT_ARRAY_SIZE,
+		.pass_on_failure = 1,
+	};
+
+	printf("%s: ", __func__);
+	expected_results[PASS_ERR_SK_SELECT_REUSEPORT] += 1;
+	do_test(type, family, &cmd, PASS_ERR_SK_SELECT_REUSEPORT);
+	printf("OK\n");
+}
+
+static void prepare_sk_fds(int type, sa_family_t family, bool inany)
+{
+	const int first = REUSEPORT_ARRAY_SIZE - 1;
+	int i, err, optval = 1;
+	struct epoll_event ev;
+	socklen_t addrlen;
+
+	if (inany)
+		sa46_init_inany(&srv_sa, family);
+	else
+		sa46_init_loopback(&srv_sa, family);
+	addrlen = sizeof(srv_sa);
+
+	/*
+	 * The sk_fds[] is filled from the back such that the order
+	 * is exactly opposite to the (struct sock_reuseport *)reuse->socks[].
+	 */
+	for (i = first; i >= 0; i--) {
+		sk_fds[i] = socket(family, type, 0);
+		CHECK(sk_fds[i] == -1, "socket()", "sk_fds[%d]:%d errno:%d\n",
+		      i, sk_fds[i], errno);
+		err = setsockopt(sk_fds[i], SOL_SOCKET, SO_REUSEPORT,
+				 &optval, sizeof(optval));
+		CHECK(err == -1, "setsockopt(SO_REUSEPORT)",
+		      "sk_fds[%d] err:%d errno:%d\n",
+		      i, err, errno);
+
+		if (i == first) {
+			err = setsockopt(sk_fds[i], SOL_SOCKET,
+					 SO_ATTACH_REUSEPORT_EBPF,
+					 &select_by_skb_data_prog,
+					 sizeof(select_by_skb_data_prog));
+			CHECK(err == -1, "setsockopt(SO_ATTACH_REUEPORT_EBPF)",
+			      "err:%d errno:%d\n", err, errno);
+		}
+
+		err = bind(sk_fds[i], (struct sockaddr *)&srv_sa, addrlen);
+		CHECK(err == -1, "bind()", "sk_fds[%d] err:%d errno:%d\n",
+		      i, err, errno);
+
+		if (type == SOCK_STREAM) {
+			err = listen(sk_fds[i], 10);
+			CHECK(err == -1, "listen()",
+			      "sk_fds[%d] err:%d errno:%d\n",
+			      i, err, errno);
+		}
+
+		err = bpf_map_update_elem(reuseport_array, &i, &sk_fds[i],
+					  BPF_NOEXIST);
+		CHECK(err == -1, "update_elem(reuseport_array)",
+		      "sk_fds[%d] err:%d errno:%d\n", i, err, errno);
+
+		if (i == first) {
+			socklen_t addrlen = sizeof(srv_sa);
+
+			err = getsockname(sk_fds[i], (struct sockaddr *)&srv_sa,
+					  &addrlen);
+			CHECK(err == -1, "getsockname()",
+			      "sk_fds[%d] err:%d errno:%d\n", i, err, errno);
+		}
+	}
+
+	epfd = epoll_create(1);
+	CHECK(epfd == -1, "epoll_create(1)",
+	      "epfd:%d errno:%d\n", epfd, errno);
+
+	ev.events = EPOLLIN;
+	for (i = 0; i < REUSEPORT_ARRAY_SIZE; i++) {
+		ev.data.u32 = i;
+		err = epoll_ctl(epfd, EPOLL_CTL_ADD, sk_fds[i], &ev);
+		CHECK(err, "epoll_ctl(EPOLL_CTL_ADD)", "sk_fds[%d]\n", i);
+	}
+}
+
+static void setup_per_test(int type, unsigned short family, bool inany)
+{
+	int ovr = -1, err;
+
+	prepare_sk_fds(type, family, inany);
+	err = bpf_map_update_elem(tmp_index_ovr_map, &index_zero, &ovr,
+				  BPF_ANY);
+	CHECK(err == -1, "update_elem(tmp_index_ovr_map, 0, -1)",
+	      "err:%d errno:%d\n", err, errno);
+}
+
+static void cleanup_per_test(void)
+{
+	int i, err;
+
+	for (i = 0; i < REUSEPORT_ARRAY_SIZE; i++)
+		close(sk_fds[i]);
+	close(epfd);
+
+	err = bpf_map_delete_elem(outer_map, &index_zero);
+	CHECK(err == -1, "delete_elem(outer_map)",
+	      "err:%d errno:%d\n", err, errno);
+}
+
+static void cleanup(void)
+{
+	close(outer_map);
+	close(reuseport_array);
+	bpf_object__close(obj);
+}
+
+static void test_all(void)
+{
+	/* Extra SOCK_STREAM to test bind_inany==true */
+	const int types[] = { SOCK_STREAM, SOCK_DGRAM, SOCK_STREAM };
+	const char * const type_strings[] = { "TCP", "UDP", "TCP" };
+	const char * const family_strings[] = { "IPv6", "IPv4" };
+	const unsigned short families[] = { AF_INET6, AF_INET };
+	const bool bind_inany[] = { false, false, true };
+	int t, f, err;
+
+	for (f = 0; f < ARRAY_SIZE(families); f++) {
+		unsigned short family = families[f];
+
+		for (t = 0; t < ARRAY_SIZE(types); t++) {
+			bool inany = bind_inany[t];
+			int type = types[t];
+
+			printf("######## %s/%s %s ########\n",
+			       family_strings[f], type_strings[t],
+				inany ? " INANY  " : "LOOPBACK");
+
+			setup_per_test(type, family, inany);
+
+			test_err_inner_map(type, family);
+
+			/* Install reuseport_array to the outer_map */
+			err = bpf_map_update_elem(outer_map, &index_zero,
+						  &reuseport_array, BPF_ANY);
+			CHECK(err == -1, "update_elem(outer_map)",
+			      "err:%d errno:%d\n", err, errno);
+
+			test_err_skb_data(type, family);
+			test_err_sk_select_port(type, family);
+			test_pass(type, family);
+			test_syncookie(type, family);
+			test_pass_on_err(type, family);
+
+			cleanup_per_test();
+			printf("\n");
+		}
+	}
+}
+
+int main(int argc, const char **argv)
+{
+	create_maps();
+	prepare_bpf_obj();
+	saved_tcp_fo = read_int_sysctl(TCP_FO_SYSCTL);
+	saved_tcp_syncookie = read_int_sysctl(TCP_SYNCOOKIE_SYSCTL);
+	enable_fastopen();
+	disable_syncookie();
+	atexit(restore_sysctls);
+
+	test_all();
+
+	cleanup();
+	return 0;
+}
diff --git a/tools/testing/selftests/bpf/test_select_reuseport_common.h b/tools/testing/selftests/bpf/test_select_reuseport_common.h
new file mode 100644
index 000000000000..08eb2a9f145f
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_select_reuseport_common.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (c) 2018 Facebook */
+
+#ifndef __TEST_SELECT_REUSEPORT_COMMON_H
+#define __TEST_SELECT_REUSEPORT_COMMON_H
+
+#include <linux/types.h>
+
+enum result {
+	DROP_ERR_INNER_MAP,
+	DROP_ERR_SKB_DATA,
+	DROP_ERR_SK_SELECT_REUSEPORT,
+	DROP_MISC,
+	PASS,
+	PASS_ERR_SK_SELECT_REUSEPORT,
+	NR_RESULTS,
+};
+
+struct cmd {
+	__u32 reuseport_index;
+	__u32 pass_on_failure;
+};
+
+struct data_check {
+	__u32 ip_protocol;
+	__u32 skb_addrs[8];
+	__u16 skb_ports[2];
+	__u16 eth_protocol;
+	__u8  bind_inany;
+	__u8  equal_check_end[0];
+
+	__u32 len;
+	__u32 hash;
+};
+
+#endif
diff --git a/tools/testing/selftests/bpf/test_select_reuseport_kern.c b/tools/testing/selftests/bpf/test_select_reuseport_kern.c
new file mode 100644
index 000000000000..5b54ec637ada
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_select_reuseport_kern.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2018 Facebook */
+
+#include <stdlib.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/bpf.h>
+#include <linux/types.h>
+#include <linux/if_ether.h>
+
+#include "bpf_endian.h"
+#include "bpf_helpers.h"
+#include "test_select_reuseport_common.h"
+
+int _version SEC("version") = 1;
+
+#ifndef offsetof
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
+
+struct bpf_map_def SEC("maps") outer_map = {
+	.type = BPF_MAP_TYPE_ARRAY_OF_MAPS,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u32),
+	.max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") result_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u32),
+	.max_entries = NR_RESULTS,
+};
+
+struct bpf_map_def SEC("maps") tmp_index_ovr_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(int),
+	.max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") linum_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(__u32),
+	.max_entries = 1,
+};
+
+struct bpf_map_def SEC("maps") data_check_map = {
+	.type = BPF_MAP_TYPE_ARRAY,
+	.key_size = sizeof(__u32),
+	.value_size = sizeof(struct data_check),
+	.max_entries = 1,
+};
+
+#define GOTO_DONE(_result) ({			\
+	result = (_result);			\
+	linum = __LINE__;			\
+	goto done;				\
+})
+
+SEC("select_by_skb_data")
+int _select_by_skb_data(struct sk_reuseport_md *reuse_md)
+{
+	__u32 linum, index = 0, flags = 0, index_zero = 0;
+	__u32 *result_cnt, *linum_value;
+	struct data_check data_check = {};
+	struct cmd *cmd, cmd_copy;
+	void *data, *data_end;
+	void *reuseport_array;
+	enum result result;
+	int *index_ovr;
+	int err;
+
+	data = reuse_md->data;
+	data_end = reuse_md->data_end;
+	data_check.len = reuse_md->len;
+	data_check.eth_protocol = reuse_md->eth_protocol;
+	data_check.ip_protocol = reuse_md->ip_protocol;
+	data_check.hash = reuse_md->hash;
+	data_check.bind_inany = reuse_md->bind_inany;
+	if (data_check.eth_protocol == bpf_htons(ETH_P_IP)) {
+		if (bpf_skb_load_bytes_relative(reuse_md,
+						offsetof(struct iphdr, saddr),
+						data_check.skb_addrs, 8,
+						BPF_HDR_START_NET))
+			GOTO_DONE(DROP_MISC);
+	} else {
+		if (bpf_skb_load_bytes_relative(reuse_md,
+						offsetof(struct ipv6hdr, saddr),
+						data_check.skb_addrs, 32,
+						BPF_HDR_START_NET))
+			GOTO_DONE(DROP_MISC);
+	}
+
+	/*
+	 * The ip_protocol could be a compile time decision
+	 * if the bpf_prog.o is dedicated to either TCP or
+	 * UDP.
+	 *
+	 * Otherwise, reuse_md->ip_protocol or
+	 * the protocol field in the iphdr can be used.
+	 */
+	if (data_check.ip_protocol == IPPROTO_TCP) {
+		struct tcphdr *th = data;
+
+		if (th + 1 > data_end)
+			GOTO_DONE(DROP_MISC);
+
+		data_check.skb_ports[0] = th->source;
+		data_check.skb_ports[1] = th->dest;
+
+		if ((th->doff << 2) + sizeof(*cmd) > data_check.len)
+			GOTO_DONE(DROP_ERR_SKB_DATA);
+		if (bpf_skb_load_bytes(reuse_md, th->doff << 2, &cmd_copy,
+				       sizeof(cmd_copy)))
+			GOTO_DONE(DROP_MISC);
+		cmd = &cmd_copy;
+	} else if (data_check.ip_protocol == IPPROTO_UDP) {
+		struct udphdr *uh = data;
+
+		if (uh + 1 > data_end)
+			GOTO_DONE(DROP_MISC);
+
+		data_check.skb_ports[0] = uh->source;
+		data_check.skb_ports[1] = uh->dest;
+
+		if (sizeof(struct udphdr) + sizeof(*cmd) > data_check.len)
+			GOTO_DONE(DROP_ERR_SKB_DATA);
+		if (data + sizeof(struct udphdr) + sizeof(*cmd) > data_end) {
+			if (bpf_skb_load_bytes(reuse_md, sizeof(struct udphdr),
+					       &cmd_copy, sizeof(cmd_copy)))
+				GOTO_DONE(DROP_MISC);
+			cmd = &cmd_copy;
+		} else {
+			cmd = data + sizeof(struct udphdr);
+		}
+	} else {
+		GOTO_DONE(DROP_MISC);
+	}
+
+	reuseport_array = bpf_map_lookup_elem(&outer_map, &index_zero);
+	if (!reuseport_array)
+		GOTO_DONE(DROP_ERR_INNER_MAP);
+
+	index = cmd->reuseport_index;
+	index_ovr = bpf_map_lookup_elem(&tmp_index_ovr_map, &index_zero);
+	if (!index_ovr)
+		GOTO_DONE(DROP_MISC);
+
+	if (*index_ovr != -1) {
+		index = *index_ovr;
+		*index_ovr = -1;
+	}
+	err = bpf_sk_select_reuseport(reuse_md, reuseport_array, &index,
+				      flags);
+	if (!err)
+		GOTO_DONE(PASS);
+
+	if (cmd->pass_on_failure)
+		GOTO_DONE(PASS_ERR_SK_SELECT_REUSEPORT);
+	else
+		GOTO_DONE(DROP_ERR_SK_SELECT_REUSEPORT);
+
+done:
+	result_cnt = bpf_map_lookup_elem(&result_map, &result);
+	if (!result_cnt)
+		return SK_DROP;
+
+	bpf_map_update_elem(&linum_map, &index_zero, &linum, BPF_ANY);
+	bpf_map_update_elem(&data_check_map, &index_zero, &data_check, BPF_ANY);
+
+	(*result_cnt)++;
+	return result < PASS ? SK_DROP : SK_PASS;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_sock.c b/tools/testing/selftests/bpf/test_sock.c
index f4d99fabc56d..b8ebe2f58074 100644
--- a/tools/testing/selftests/bpf/test_sock.c
+++ b/tools/testing/selftests/bpf/test_sock.c
@@ -14,10 +14,7 @@
 
 #include "cgroup_helpers.h"
 #include "bpf_rlimit.h"
-
-#ifndef ARRAY_SIZE
-# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-#endif
+#include "bpf_util.h"
 
 #define CG_PATH		"/foo"
 #define MAX_INSNS	512
diff --git a/tools/testing/selftests/bpf/test_sock_addr.c b/tools/testing/selftests/bpf/test_sock_addr.c
index 2e45c92d1111..aeeb76a54d63 100644
--- a/tools/testing/selftests/bpf/test_sock_addr.c
+++ b/tools/testing/selftests/bpf/test_sock_addr.c
@@ -20,15 +20,12 @@
 
 #include "cgroup_helpers.h"
 #include "bpf_rlimit.h"
+#include "bpf_util.h"
 
 #ifndef ENOTSUPP
 # define ENOTSUPP 524
 #endif
 
-#ifndef ARRAY_SIZE
-# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-#endif
-
 #define CG_PATH	"/foo"
 #define CONNECT4_PROG_PATH	"./connect4_prog.o"
 #define CONNECT6_PROG_PATH	"./connect6_prog.o"
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 452cf5c6c784..67c412d19c09 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -42,12 +42,9 @@
 #endif
 #include "bpf_rlimit.h"
 #include "bpf_rand.h"
+#include "bpf_util.h"
 #include "../../../include/linux/filter.h"
 
-#ifndef ARRAY_SIZE
-# define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
-#endif
-
 #define MAX_INSNS	BPF_MAXINSNS
 #define MAX_FIXUPS	8
 #define MAX_NR_MAPS	8