selftests: mptcp: join: userspace: longer transfer

In rare cases, when the test environment is very slow, some userspace
tests can fail because some expected events have not been seen.

Because the tests are expecting a long on-going connection, and they are
not waiting for the end of the transfer, it is fine to make the
connection longer. This connection will be killed at the end, after the
verifications, so making it longer doesn't change anything, apart from
avoid it to end before the end of the verifications

To play it safe, all userspace tests not waiting for the end of the
transfer are now sharing a longer file (128KB) at slow speed.

Fixes: 4369c19 ("selftests: mptcp: test userspace pm out of transfer")
Cc: stable@vger.kernel.org
Fixes: b2e2248 ("selftests: mptcp: userspace pm create id 0 subflow")
Fixes: e3b47e4 ("selftests: mptcp: userspace pm remove initial subflow")
Fixes: b9fb176 ("selftests: mptcp: userspace pm send RM_ADDR for ID 0")
Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251110-net-mptcp-sft-join-unstable-v1-4-a4332c714e10@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: matttbe

tools/testing/selftests/net/mptcp/mptcp_join.sh

@@ -3806,7 +3806,7 @@ userspace_tests()
 	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
 		set_userspace_pm $ns1
 		pm_nl_set_limits $ns2 2 2
-		{ speed=5 \
+		{ test_linkfail=128 speed=5 \
 			run_tests $ns1 $ns2 10.0.1.1 & } 2>/dev/null
 		local tests_pid=$!
 		wait_mpj $ns1
@@ -3839,7 +3839,7 @@ userspace_tests()
 	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
 		set_userspace_pm $ns2
 		pm_nl_set_limits $ns1 0 1
-		{ speed=5 \
+		{ test_linkfail=128 speed=5 \
 			run_tests $ns1 $ns2 10.0.1.1 & } 2>/dev/null
 		local tests_pid=$!
 		wait_mpj $ns2
@@ -3867,7 +3867,7 @@ userspace_tests()
 	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
 		set_userspace_pm $ns2
 		pm_nl_set_limits $ns1 0 1
-		{ speed=5 \
+		{ test_linkfail=128 speed=5 \
 			run_tests $ns1 $ns2 10.0.1.1 & } 2>/dev/null
 		local tests_pid=$!
 		wait_mpj $ns2
@@ -3888,7 +3888,7 @@ userspace_tests()
 	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
 		set_userspace_pm $ns2
 		pm_nl_set_limits $ns1 0 1
-		{ speed=5 \
+		{ test_linkfail=128 speed=5 \
 			run_tests $ns1 $ns2 10.0.1.1 & } 2>/dev/null
 		local tests_pid=$!
 		wait_mpj $ns2
@@ -3912,7 +3912,7 @@ userspace_tests()
 	   continue_if mptcp_lib_has_file '/proc/sys/net/mptcp/pm_type'; then
 		set_userspace_pm $ns1
 		pm_nl_set_limits $ns2 1 1
-		{ speed=5 \
+		{ test_linkfail=128 speed=5 \
 			run_tests $ns1 $ns2 10.0.1.1 & } 2>/dev/null
 		local tests_pid=$!
 		wait_mpj $ns1