selftests: mptcp: join: add ss mptcp support check

Commands 'ss -M' are used in script mptcp_join.sh to display only MPTCP
sockets. So it must be checked if ss tool supports MPTCP in this script.

Fixes: e274f7154008 ("selftests: mptcp: add subflow limits test-cases")
Cc: stable@vger.kernel.org
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://lore.kernel.org/r/20240223-upstream-net-20240223-misc-fixes-v1-7-162e87e48497@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index e68b1bc2c2e470e59fdba8fe905626f15dc17eab..e4581b0dfb967723e36b1847c512f02f4bc87a45 100755 (executable)
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -161,6 +161,11 @@ check_tools()
                exit $ksft_skip
        fi
 
+       if ! ss -h | grep -q MPTCP; then
+               echo "SKIP: ss tool does not support MPTCP"
+               exit $ksft_skip
+       fi
+
        # Use the legacy version if available to support old kernel versions
        if iptables-legacy -V &> /dev/null; then
                iptables="iptables-legacy"