selftests: mptcp: userspace pm: validate deny-join-id0 flag

commit 24733e193a0d68f20d220e86da0362460c9aa812 upstream.

The previous commit adds the MPTCP_PM_EV_FLAG_DENY_JOIN_ID0 flag. Make
sure it is correctly announced by the other peer when it has been
received.

pm_nl_ctl will now display 'deny_join_id0:1' when monitoring the events,
and when this flag was set by the other peer.

The 'Fixes' tag here below is the same as the one from the previous
commit: this patch here is not fixing anything wrong in the selftests,
but it validates the previous fix for an issue introduced by this commit
ID.

Fixes: 702c2f646d42 ("mptcp: netlink: allow userspace-driven subflow establishment")
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20250912-net-mptcp-pm-uspace-deny_join_id0-v1-3-40171884ade8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[ Conflict in userspace_pm.sh, because of a difference in the context,
  introduced by commit c66fb480a330 ("selftests: userspace pm: avoid
  relaunching pm events"), which is not in this version. The same lines
  can still be added at the same place.
  Conflicts in userspace_pm.sh, because of different refactoring, like
  with commit ae1fa39da991 ("selftests: mptcp: add evts_get_info
  helper"), and commit e198ad759273 ("selftests: mptcp: userspace_pm:
  uniform results printing"). The modifications have been adapted to the
  old version, without the new helpers. ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
index 1887bd61bd9a5f5818a7e06e47ecb627bac35205..17e5b7ec53b67c73fb11aebbf0f0766df62a9943 100644 (file)
--- a/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
+++ b/tools/testing/selftests/net/mptcp/pm_nl_ctl.c
@@ -188,6 +188,13 @@ static int capture_events(int fd, int event_group)
                                        fprintf(stderr, ",error:%u", *(__u8 *)RTA_DATA(attrs));
                                else if (attrs->rta_type == MPTCP_ATTR_SERVER_SIDE)
                                        fprintf(stderr, ",server_side:%u", *(__u8 *)RTA_DATA(attrs));
+                               else if (attrs->rta_type == MPTCP_ATTR_FLAGS) {
+                                       __u16 flags = *(__u16 *)RTA_DATA(attrs);
+
+                                       /* only print when present, easier */
+                                       if (flags & MPTCP_PM_EV_FLAG_DENY_JOIN_ID0)
+                                               fprintf(stderr, ",deny_join_id0:1");
+                               }
 
                                attrs = RTA_NEXT(attrs, msg_len);
                        }

diff --git a/tools/testing/selftests/net/mptcp/userspace_pm.sh b/tools/testing/selftests/net/mptcp/userspace_pm.sh
index cb6c28d4012936fd27e6e72458be3ecf9ed73cb9..a82ac12e816d14b049adf9dd1ad1142da423f63d 100755 (executable)
--- a/tools/testing/selftests/net/mptcp/userspace_pm.sh
+++ b/tools/testing/selftests/net/mptcp/userspace_pm.sh
@@ -139,6 +139,9 @@ make_connection()
                is_v6="v4"
        fi
 
+       # set this on the client side only: will not affect the rest
+       ip netns exec "$ns2" sysctl -q net.mptcp.allow_join_initial_addr_port=0
+
        # Capture netlink events over the two network namespaces running
        # the MPTCP client and server
        local client_evts
@@ -173,21 +176,28 @@ make_connection()
        local client_token
        local client_port
        local client_serverside
+       local client_nojoin
        local server_token
        local server_serverside
+       local server_nojoin
 
        client_token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
        client_port=$(sed --unbuffered -n 's/.*\(sport:\)\([[:digit:]]*\).*$/\2/p;q' "$client_evts")
        client_serverside=$(sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q'\
                                      "$client_evts")
+       client_nojoin=$(sed --unbuffered -n 's/.*\(deny_join_id0:\)\([[:digit:]]*\).*$/\2/p;q'\
+                                     "$client_evts")
        kill_wait $server_evts_pid
        server_token=$(sed --unbuffered -n 's/.*\(token:\)\([[:digit:]]*\).*$/\2/p;q' "$server_evts")
        server_serverside=$(sed --unbuffered -n 's/.*\(server_side:\)\([[:digit:]]*\).*$/\2/p;q'\
                                      "$server_evts")
+       server_nojoin=$(sed --unbuffered -n 's/.*\(deny_join_id0:\)\([[:digit:]]*\).*$/\2/p;q'\
+                                     "$server_evts")
        rm -f "$client_evts" "$server_evts" "$file"
 
-       if [ "$client_token" != "" ] && [ "$server_token" != "" ] && [ "$client_serverside" = 0 ] &&
-                  [ "$server_serverside" = 1 ]
+       if [ "${client_token}" != "" ] && [ "${server_token}" != "" ] &&
+          [ "${client_serverside}" = 0 ] && [ "${server_serverside}" = 1 ] &&
+          [ "${client_nojoin:-0}" = 0 ] && [ "${server_nojoin:-0}" = 1 ]
        then
                stdbuf -o0 -e0 printf "Established IP%s MPTCP Connection ns2 => ns1    \t\t[OK]\n" $is_v6
        else