4 files changed, 43 insertions, 4 deletions
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index d1f837579398..6ed7e65de494 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -117,7 +117,7 @@ bool inet_rcv_saddr_any(const struct sock *sk)
 	return !sk->sk_rcv_saddr;
 }
 
-void inet_get_local_port_range(struct net *net, int *low, int *high)
+void inet_get_local_port_range(const struct net *net, int *low, int *high)
 {
 	unsigned int seq;
 
@@ -130,6 +130,27 @@ void inet_get_local_port_range(struct net *net, int *low, int *high)
 }
 EXPORT_SYMBOL(inet_get_local_port_range);
 
+void inet_sk_get_local_port_range(const struct sock *sk, int *low, int *high)
+{
+	const struct inet_sock *inet = inet_sk(sk);
+	const struct net *net = sock_net(sk);
+	int lo, hi, sk_lo, sk_hi;
+
+	inet_get_local_port_range(net, &lo, &hi);
+
+	sk_lo = inet->local_port_range.lo;
+	sk_hi = inet->local_port_range.hi;
+
+	if (unlikely(lo <= sk_lo && sk_lo <= hi))
+		lo = sk_lo;
+	if (unlikely(lo <= sk_hi && sk_hi <= hi))
+		hi = sk_hi;
+
+	*low = lo;
+	*high = hi;
+}
+EXPORT_SYMBOL(inet_sk_get_local_port_range);
+
 static bool inet_use_bhash2_on_bind(const struct sock *sk)
 {
 #if IS_ENABLED(CONFIG_IPV6)
@@ -316,7 +337,7 @@ inet_csk_find_open_port(const struct sock *sk, struct inet_bind_bucket **tb_ret,
 ports_exhausted:
 	attempt_half = (sk->sk_reuse == SK_CAN_REUSE) ? 1 : 0;
 other_half_scan:
-	inet_get_local_port_range(net, &low, &high);
+	inet_sk_get_local_port_range(sk, &low, &high);
 	high++; /* [32768, 60999] -> [32768, 61000[ */
 	if (high - low < 4)
 		attempt_half = 0;
diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
index 7a13dd7f546b..e41fdc38ce19 100644
--- a/net/ipv4/inet_hashtables.c
+++ b/net/ipv4/inet_hashtables.c
@@ -1016,7 +1016,7 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row,
 
 	l3mdev = inet_sk_bound_l3mdev(sk);
 
-	inet_get_local_port_range(net, &low, &high);
+	inet_sk_get_local_port_range(sk, &low, &high);
 	high++; /* [32768, 60999] -> [32768, 61000[ */
 	remaining = high - low;
 	if (likely(remaining > 1))
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index 9f92ae35bb01..b511ff0adc0a 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -923,6 +923,7 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
 	case IP_CHECKSUM:
 	case IP_RECVFRAGSIZE:
 	case IP_RECVERR_RFC4884:
+	case IP_LOCAL_PORT_RANGE:
 		if (optlen >= sizeof(int)) {
 			if (copy_from_sockptr(&val, optval, sizeof(val)))
 				return -EFAULT;
@@ -1365,6 +1366,20 @@ int do_ip_setsockopt(struct sock *sk, int level, int optname,
 		WRITE_ONCE(inet->min_ttl, val);
 		break;
 
+	case IP_LOCAL_PORT_RANGE:
+	{
+		const __u16 lo = val;
+		const __u16 hi = val >> 16;
+
+		if (optlen != sizeof(__u32))
+			goto e_inval;
+		if (lo != 0 && hi != 0 && lo > hi)
+			goto e_inval;
+
+		inet->local_port_range.lo = lo;
+		inet->local_port_range.hi = hi;
+		break;
+	}
 	default:
 		err = -ENOPROTOOPT;
 		break;
@@ -1743,6 +1758,9 @@ int do_ip_getsockopt(struct sock *sk, int level, int optname,
 	case IP_MINTTL:
 		val = inet->min_ttl;
 		break;
+	case IP_LOCAL_PORT_RANGE:
+		val = inet->local_port_range.hi << 16 | inet->local_port_range.lo;
+		break;
 	default:
 		sockopt_release_sock(sk);
 		return -ENOPROTOOPT;
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 9592fe3e444a..c605d171eb2d 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -248,7 +248,7 @@ int udp_lib_get_port(struct sock *sk, unsigned short snum,
 		int low, high, remaining;
 		unsigned int rand;
 
-		inet_get_local_port_range(net, &low, &high);
+		inet_sk_get_local_port_range(sk, &low, &high);
 		remaining = (high - low) + 1;
 
 		rand = get_random_u32();