diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index bdb981c204fa..78046c570596 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -233,6 +233,7 @@ enum bpf_arg_type {
 	ARG_CONST_SIZE_OR_ZERO,	/* number of bytes accessed from memory or 0 */
 
 	ARG_PTR_TO_CTX,		/* pointer to context */
+	ARG_PTR_TO_CTX_OR_NULL,	/* pointer to context or NULL */
 	ARG_ANYTHING,		/* any (initialized) argument is ok */
 	ARG_PTR_TO_SPIN_LOCK,	/* pointer to bpf_spin_lock */
 	ARG_PTR_TO_SOCK_COMMON,	/* pointer to sock_common */
diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h
index 854d39ef1ca3..1c6edfdb9a2c 100644
--- a/include/net/net_namespace.h
+++ b/include/net/net_namespace.h
@@ -168,6 +168,9 @@ struct net {
 #ifdef CONFIG_XFRM
 	struct netns_xfrm	xfrm;
 #endif
+
+	atomic64_t		net_cookie; /* written once */
+
 #if IS_ENABLED(CONFIG_IP_VS)
 	struct netns_ipvs	*ipvs;
 #endif
@@ -273,6 +276,8 @@ static inline int check_net(const struct net *net)
 
 void net_drop_ns(void *);
 
+u64 net_gen_cookie(struct net *net);
+
 #else
 
 static inline struct net *get_net(struct net *net)
@@ -300,6 +305,11 @@ static inline int check_net(const struct net *net)
 	return 1;
 }
 
+static inline u64 net_gen_cookie(struct net *net)
+{
+	return 0;
+}
+
 #define net_drop_ns NULL
 #endif
 
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 5d01c5c7e598..bd81c4555206 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -2950,6 +2950,19 @@ union bpf_attr {
  *		restricted to raw_tracepoint bpf programs.
  *	Return
  *		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_get_netns_cookie(void *ctx)
+ * 	Description
+ * 		Retrieve the cookie (generated by the kernel) of the network
+ * 		namespace the input *ctx* is associated with. The network
+ * 		namespace cookie remains stable for its lifetime and provides
+ * 		a global identifier that can be assumed unique. If *ctx* is
+ * 		NULL, then the helper returns the cookie for the initial
+ * 		network namespace. The cookie itself is very similar to that
+ * 		of bpf_get_socket_cookie() helper, but for network namespaces
+ * 		instead of sockets.
+ * 	Return
+ * 		A 8-byte long opaque number.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -3073,7 +3086,8 @@ union bpf_attr {
 	FN(jiffies64),			\
 	FN(read_branch_records),	\
 	FN(get_ns_current_pid_tgid),	\
-	FN(xdp_output),
+	FN(xdp_output),			\
+	FN(get_netns_cookie),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 2ea2a868324e..46ba86c540e2 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3461,13 +3461,17 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 regno,
 		expected_type = CONST_PTR_TO_MAP;
 		if (type != expected_type)
 			goto err_type;
-	} else if (arg_type == ARG_PTR_TO_CTX) {
+	} else if (arg_type == ARG_PTR_TO_CTX ||
+		   arg_type == ARG_PTR_TO_CTX_OR_NULL) {
 		expected_type = PTR_TO_CTX;
-		if (type != expected_type)
-			goto err_type;
-		err = check_ctx_reg(env, reg, regno);
-		if (err < 0)
-			return err;
+		if (!(register_is_null(reg) &&
+		      arg_type == ARG_PTR_TO_CTX_OR_NULL)) {
+			if (type != expected_type)
+				goto err_type;
+			err = check_ctx_reg(env, reg, regno);
+			if (err < 0)
+				return err;
+		}
 	} else if (arg_type == ARG_PTR_TO_SOCK_COMMON) {
 		expected_type = PTR_TO_SOCK_COMMON;
 		/* Any sk pointer can be ARG_PTR_TO_SOCK_COMMON */
diff --git a/net/core/filter.c b/net/core/filter.c
index 6cb7e0e24473..e249a499cbe5 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -4141,6 +4141,39 @@ static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
 	.arg1_type	= ARG_PTR_TO_CTX,
 };
 
+static u64 __bpf_get_netns_cookie(struct sock *sk)
+{
+#ifdef CONFIG_NET_NS
+	return net_gen_cookie(sk ? sk->sk_net.net : &init_net);
+#else
+	return 0;
+#endif
+}
+
+BPF_CALL_1(bpf_get_netns_cookie_sock, struct sock *, ctx)
+{
+	return __bpf_get_netns_cookie(ctx);
+}
+
+static const struct bpf_func_proto bpf_get_netns_cookie_sock_proto = {
+	.func		= bpf_get_netns_cookie_sock,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
+};
+
+BPF_CALL_1(bpf_get_netns_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
+{
+	return __bpf_get_netns_cookie(ctx ? ctx->sk : NULL);
+}
+
+static const struct bpf_func_proto bpf_get_netns_cookie_sock_addr_proto = {
+	.func		= bpf_get_netns_cookie_sock_addr,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX_OR_NULL,
+};
+
 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
 {
 	struct sock *sk = sk_to_full_sk(skb->sk);
@@ -5968,6 +6001,8 @@ sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_get_local_storage_proto;
 	case BPF_FUNC_get_socket_cookie:
 		return &bpf_get_socket_cookie_sock_proto;
+	case BPF_FUNC_get_netns_cookie:
+		return &bpf_get_netns_cookie_sock_proto;
 	case BPF_FUNC_perf_event_output:
 		return &bpf_event_output_data_proto;
 	default:
@@ -5994,6 +6029,8 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		}
 	case BPF_FUNC_get_socket_cookie:
 		return &bpf_get_socket_cookie_sock_addr_proto;
+	case BPF_FUNC_get_netns_cookie:
+		return &bpf_get_netns_cookie_sock_addr_proto;
 	case BPF_FUNC_get_local_storage:
 		return &bpf_get_local_storage_proto;
 	case BPF_FUNC_perf_event_output:
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 757cc1d084e7..190ca66a383b 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -69,6 +69,20 @@ EXPORT_SYMBOL_GPL(pernet_ops_rwsem);
 
 static unsigned int max_gen_ptrs = INITIAL_NET_GEN_PTRS;
 
+static atomic64_t cookie_gen;
+
+u64 net_gen_cookie(struct net *net)
+{
+	while (1) {
+		u64 res = atomic64_read(&net->net_cookie);
+
+		if (res)
+			return res;
+		res = atomic64_inc_return(&cookie_gen);
+		atomic64_cmpxchg(&net->net_cookie, 0, res);
+	}
+}
+
 static struct net_generic *net_alloc_generic(void)
 {
 	struct net_generic *ng;
@@ -1087,6 +1101,7 @@ static int __init net_ns_init(void)
 		panic("Could not allocate generic netns");
 
 	rcu_assign_pointer(init_net.gen, ng);
+	net_gen_cookie(&init_net);
 
 	down_write(&pernet_ops_rwsem);
 	if (setup_net(&init_net, &init_user_ns))
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 5d01c5c7e598..bd81c4555206 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -2950,6 +2950,19 @@ union bpf_attr {
  *		restricted to raw_tracepoint bpf programs.
  *	Return
  *		0 on success, or a negative error in case of failure.
+ *
+ * u64 bpf_get_netns_cookie(void *ctx)
+ * 	Description
+ * 		Retrieve the cookie (generated by the kernel) of the network
+ * 		namespace the input *ctx* is associated with. The network
+ * 		namespace cookie remains stable for its lifetime and provides
+ * 		a global identifier that can be assumed unique. If *ctx* is
+ * 		NULL, then the helper returns the cookie for the initial
+ * 		network namespace. The cookie itself is very similar to that
+ * 		of bpf_get_socket_cookie() helper, but for network namespaces
+ * 		instead of sockets.
+ * 	Return
+ * 		A 8-byte long opaque number.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -3073,7 +3086,8 @@ union bpf_attr {
 	FN(jiffies64),			\
 	FN(read_branch_records),	\
 	FN(get_ns_current_pid_tgid),	\
-	FN(xdp_output),
+	FN(xdp_output),			\
+	FN(get_netns_cookie),
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
  * function eBPF program intends to call