From: Geliang Tang <tanggeliang@kylinos.cn>

TCP_ULP was obtained by calling mptcp_getsockopt_first_sf_only() to get
the ULP of the first subflow. Now that the mechanism has changed, a new
helper needs to be implemented to get the ULP of the msk.

Co-developed-by: Gang Yan <yangang@kylinos.cn>
Signed-off-by: Gang Yan <yangang@kylinos.cn>
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 net/mptcp/sockopt.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/net/mptcp/sockopt.c b/net/mptcp/sockopt.c
index de90a2897d2d..f3db4f2e8f81 100644
--- a/net/mptcp/sockopt.c
+++ b/net/mptcp/sockopt.c
@@ -1393,6 +1393,17 @@ static int mptcp_put_int_option(struct mptcp_sock *msk, char __user *optval,
 	return 0;
 }
 
+static int mptcp_getsockopt_msk(struct sock *sk, int level, int optname,
+				char __user *optval, int __user *optlen)
+{
+	int ret;
+
+	lock_sock(sk);
+	ret = tcp_getsockopt(sk, level, optname, optval, optlen);
+	release_sock(sk);
+	return ret;
+}
+
 static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 				    char __user *optval, int __user *optlen)
 {
@@ -1400,6 +1411,7 @@ static int mptcp_getsockopt_sol_tcp(struct mptcp_sock *msk, int optname,
 
 	switch (optname) {
 	case TCP_ULP:
+		return mptcp_getsockopt_msk(sk, SOL_TCP, optname, optval, optlen);
 	case TCP_CONGESTION:
 	case TCP_INFO:
 	case TCP_CC_INFO:
-- 
2.51.0