--- x/include/net/inet_sock.h
+++ y/include/net/inet_sock.h
@@ -227,6 +227,7 @@ struct inet_sock {
 	__be16			inet_sport;
 	struct ip_options_rcu __rcu	*inet_opt;
 	atomic_t		inet_id;
+	spinlock_t		inet_lock;
 
 	__u8			tos;
 	__u8			min_ttl;
--- x/net/ipv4/af_inet.c
+++ y/net/ipv4/af_inet.c
@@ -351,6 +351,7 @@ lookup_protocol:
 		inet->pmtudisc = IP_PMTUDISC_WANT;
 
 	atomic_set(&inet->inet_id, 0);
+	spin_lock_init(&inet->inet_lock);
 
 	sock_init_data(sock, sk);
 
--- x/net/ipv4/ip_sockglue.c
+++ y/net/ipv4/ip_sockglue.c
@@ -1087,6 +1087,7 @@ int do_ip_setsockopt(struct sock *sk, in
 		err = ip_options_get(sock_net(sk), &opt, optval, optlen);
 		if (err)
 			break;
+		spin_lock(&inet->inet_lock);
 		old = rcu_dereference_protected(inet->inet_opt,
 						lockdep_sock_is_held(sk));
 		if (inet_test_bit(IS_ICSK, sk)) {
@@ -1109,6 +1110,7 @@ int do_ip_setsockopt(struct sock *sk, in
 		rcu_assign_pointer(inet->inet_opt, opt);
 		if (old)
 			kfree_rcu(old, rcu);
+		spin_unlock(&inet->inet_lock);
 		break;
 	}
 	case IP_CHECKSUM:
--- x/net/ipv4/cipso_ipv4.c
+++ y/net/ipv4/cipso_ipv4.c
@@ -1900,6 +1900,7 @@ int cipso_v4_sock_setattr(struct sock *s
 	buf = NULL;
 
 	sk_inet = inet_sk(sk);
+	spin_lock(&sk_inet->inet_lock);
 
 	old = rcu_dereference_protected(sk_inet->inet_opt, sk_locked);
 	if (inet_test_bit(IS_ICSK, sk)) {
@@ -1912,6 +1913,7 @@ int cipso_v4_sock_setattr(struct sock *s
 	rcu_assign_pointer(sk_inet->inet_opt, opt);
 	if (old)
 		kfree_rcu(old, rcu);
+	spin_unlock(&sk_inet->inet_lock);
 
 	return 0;
 
@@ -2059,7 +2061,9 @@ void cipso_v4_sock_delattr(struct sock *
 
 	sk_inet = inet_sk(sk);
 
+	spin_lock(&sk_inet->inet_lock);
 	hdr_delta = cipso_v4_delopt(&sk_inet->inet_opt);
+	spin_unlock(&sk_inet->inet_lock);
 	if (inet_test_bit(IS_ICSK, sk) && hdr_delta > 0) {
 		struct inet_connection_sock *sk_conn = inet_csk(sk);
 		sk_conn->icsk_ext_hdr_len -= hdr_delta;