[PATCH 6.1.y] selftests: mptcp: join: check re-re-adding ID 0 signal

["Matthieu Baerts (NGI0)" <matttbe@kernel.org>]

commit f18fa2abf81099d822d842a107f8c9889c86043c upstream.

This test extends "delete re-add signal" to validate the previous
commit: when the 'signal' endpoint linked to the initial subflow (ID 0)
is re-added multiple times, it will re-send the ADD_ADDR with id 0. The
client should still be able to re-create this subflow, even if the
add_addr_accepted limit has been reached as this special address is not
considered as a new address.

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: d0876b2284cf ("mptcp: add the incoming RM_ADDR support")
Cc: stable@vger.kernel.org
Reviewed-by: Mat Martineau <martineau@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
[ Conflicts in mptcp_join.sh, because the helpers are different in this
  version:
  - run_tests has been modified a few times to reduce the number of
    positional parameters
  - no chk_mptcp_info helper
  - chk_subflow_nr taking an extra parameter
  - kill_tests_wait instead of mptcp_lib_kill_wait ]
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
---
 .../testing/selftests/net/mptcp/mptcp_join.sh | 30 ++++++++++++-------
 1 file changed, 19 insertions(+), 11 deletions(-)

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 79a39e30842b..20561d569697 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -3390,7 +3390,7 @@ endpoint_tests()
 		# broadcast IP: no packet for this address will be received on ns1
 		pm_nl_add_endpoint $ns1 224.0.0.1 id 2 flags signal
 		pm_nl_add_endpoint $ns1 10.0.1.1 id 42 flags signal
-		run_tests $ns1 $ns2 10.0.1.1 4 0 0 speed_20 2>/dev/null &
+		run_tests $ns1 $ns2 10.0.1.1 4 0 0 speed_5 2>/dev/null &
 		local tests_pid=$!
 
 		wait_mpj $ns2
@@ -3412,7 +3412,15 @@ endpoint_tests()
 
 		pm_nl_add_endpoint $ns1 10.0.1.1 id 99 flags signal
 		wait_mpj $ns2
-		chk_subflow_nr "" "after re-add" 3
+		chk_subflow_nr "" "after re-add ID 0" 3
+
+		pm_nl_del_endpoint $ns1 99 10.0.1.1
+		sleep 0.5
+		chk_subflow_nr "" "after re-delete ID 0" 2
+
+		pm_nl_add_endpoint $ns1 10.0.1.1 id 88 flags signal
+		wait_mpj $ns2
+		chk_subflow_nr "" "after re-re-add ID 0" 3
 
 		kill_wait "${tests_pid}"
 		kill_events_pids
@@ -3422,19 +3430,19 @@ endpoint_tests()
 		chk_evt_nr ns1 MPTCP_LIB_EVENT_ESTABLISHED 1
 		chk_evt_nr ns1 MPTCP_LIB_EVENT_ANNOUNCED 0
 		chk_evt_nr ns1 MPTCP_LIB_EVENT_REMOVED 0
-		chk_evt_nr ns1 MPTCP_LIB_EVENT_SUB_ESTABLISHED 4
-		chk_evt_nr ns1 MPTCP_LIB_EVENT_SUB_CLOSED 2
+		chk_evt_nr ns1 MPTCP_LIB_EVENT_SUB_ESTABLISHED 5
+		chk_evt_nr ns1 MPTCP_LIB_EVENT_SUB_CLOSED 3
 
 		chk_evt_nr ns2 MPTCP_LIB_EVENT_CREATED 1
 		chk_evt_nr ns2 MPTCP_LIB_EVENT_ESTABLISHED 1
-		chk_evt_nr ns2 MPTCP_LIB_EVENT_ANNOUNCED 5
-		chk_evt_nr ns2 MPTCP_LIB_EVENT_REMOVED 3
-		chk_evt_nr ns2 MPTCP_LIB_EVENT_SUB_ESTABLISHED 4
-		chk_evt_nr ns2 MPTCP_LIB_EVENT_SUB_CLOSED 2
+		chk_evt_nr ns2 MPTCP_LIB_EVENT_ANNOUNCED 6
+		chk_evt_nr ns2 MPTCP_LIB_EVENT_REMOVED 4
+		chk_evt_nr ns2 MPTCP_LIB_EVENT_SUB_ESTABLISHED 5
+		chk_evt_nr ns2 MPTCP_LIB_EVENT_SUB_CLOSED 3
 
-		chk_join_nr 4 4 4
-		chk_add_nr 5 5
-		chk_rm_nr 3 2 invert
+		chk_join_nr 5 5 5
+		chk_add_nr 6 6
+		chk_rm_nr 4 3 invert
 	fi
 
 	# flush and re-add
-- 
2.45.2