From: Geliang Tang <tanggeliang@kylinos.cn>

Add tests for IP_LOCAL_PORT_RANGE:
- Sets port range to 30000-31000
- Verifies the range via getsockopt
- Covers both IPv4 and IPv6
- Reports results in test script

Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
---
 .../selftests/net/mptcp/mptcp_sockopt.c       | 25 +++++++++++++++++++
 .../selftests/net/mptcp/mptcp_sockopt.sh      |  8 ++++++
 2 files changed, 33 insertions(+)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
index 02b7ec774b86..3e2072869527 100644
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.c
@@ -280,6 +280,15 @@ static void do_setsockopt_bind_address_no_port(int fd)
 		perror("setsockopt(IP_BIND_ADDRESS_NO_PORT)");
 }
 
+static void do_setsockopt_local_port_range(int fd)
+{
+	uint32_t port_range = (31000 << 16 | 30000); // [30000 - 31000]
+
+	if (setsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE, &port_range,
+		       sizeof(port_range)))
+		perror("setsockopt(IP_LOCAL_PORT_RANGE)");
+}
+
 static void do_setsockopts(int fd)
 {
 	do_setsockopt_reuseaddr(fd);
@@ -290,6 +299,7 @@ static void do_setsockopts(int fd)
 	do_setsockopt_freebind(fd);
 	do_setsockopt_transparent(fd);
 	do_setsockopt_bind_address_no_port(fd);
+	do_setsockopt_local_port_range(fd);
 }
 
 static int sock_listen_mptcp(const char * const listenaddr,
@@ -797,6 +807,19 @@ static void do_getsockopt_bind_address_no_port(int fd)
 	assert(enable == 1);
 }
 
+static void do_getsockopt_local_port_range(int fd)
+{
+	uint32_t port_range;
+	socklen_t len;
+
+	len = sizeof(port_range);
+	if (getsockopt(fd, SOL_IP, IP_LOCAL_PORT_RANGE,
+		       &port_range, &len))
+		die_perror("getsockopt(IP_LOCAL_PORT_RANGE)");
+
+	assert(port_range == (31000 << 16 | 30000));
+}
+
 static void do_getsockopts(struct so_state *s, int fd, size_t r, size_t w)
 {
 	do_getsockopt_mptcp_info(s, fd, w);
@@ -823,6 +846,8 @@ static void do_getsockopts(struct so_state *s, int fd, size_t r, size_t w)
 	do_getsockopt_transparent(fd);
 
 	do_getsockopt_bind_address_no_port(fd);
+
+	do_getsockopt_local_port_range(fd);
 }
 
 static void connect_one_server(int fd, int pipefd)
diff --git a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
index 1bee46c9b29a..a688917a13c1 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_sockopt.sh
@@ -305,6 +305,10 @@ do_mptcp_sockopt_tests()
 	mptcp_lib_pr_ok
 	mptcp_lib_result_pass "IP_BIND_ADDRESS_NO_PORT sockopt v4"
 
+	print_title "IP_LOCAL_PORT_RANGE sockopt v4"
+	mptcp_lib_pr_ok
+	mptcp_lib_result_pass "IP_LOCAL_PORT_RANGE sockopt v4"
+
 	ip netns exec "$ns_sbox" ./mptcp_sockopt -6
 	lret=$?
 
@@ -351,6 +355,10 @@ do_mptcp_sockopt_tests()
 	print_title "IP_BIND_ADDRESS_NO_PORT sockopt v6"
 	mptcp_lib_pr_ok
 	mptcp_lib_result_pass "IP_BIND_ADDRESS_NO_PORT sockopt v6"
+
+	print_title "IP_LOCAL_PORT_RANGE sockopt v6"
+	mptcp_lib_pr_ok
+	mptcp_lib_result_pass "IP_LOCAL_PORT_RANGE sockopt v6"
 }
 
 run_tests()
-- 
2.48.1