Commit c5d5ecf21fdd for kernel

commit c5d5ecf21fdd9ce91e6116feb3aa83cee73352cc
Author: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Date:   Tue Jan 27 20:27:27 2026 +0100

    selftests: mptcp: join: fix local endp not being tracked

    When running this mptcp_join.sh selftest on older kernel versions not
    supporting local endpoints tracking, this test fails because 3 MP_JOIN
    ACKs have been received, while only 2 were expected.

    It is not clear why only 2 MP_JOIN ACKs were expected on old kernel
    versions, while 3 MP_JOIN SYN and SYN+ACK were expected. When testing on
    the v5.15.197 kernel, 3 MP_JOIN ACKs are seen, which is also what is
    expected in the selftests included in this kernel version, see commit
    f4480eaad489 ("selftests: mptcp: add missing join check").

    Switch the expected MP_JOIN ACKs to 3. While at it, move this
    chk_join_nr helper out of the special condition for older kernel
    versions as it is now the same as with more recent ones. Also, invert
    the condition to be more logical: what's expected on newer kernel
    versions having such helper first.

    Fixes: d4c81bbb8600 ("selftests: mptcp: join: support local endpoint being tracked or not")
    Cc: stable@vger.kernel.org
    Reviewed-by: Mat Martineau <martineau@kernel.org>
    Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
    Link: https://patch.msgid.link/20260127-net-mptcp-dup-nl-events-v1-5-7f71e1bc4feb@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 3fc29201362a..e70d3420954f 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -2329,17 +2329,16 @@ signal_address_tests()
 		ip netns exec $ns1 sysctl -q net.mptcp.add_addr_timeout=1
 		speed=slow \
 			run_tests $ns1 $ns2 10.0.1.1
+		chk_join_nr 3 3 3

 		# It is not directly linked to the commit introducing this
 		# symbol but for the parent one which is linked anyway.
-		if ! mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
-			chk_join_nr 3 3 2
-			chk_add_nr 4 4
-		else
-			chk_join_nr 3 3 3
+		if mptcp_lib_kallsyms_has "mptcp_pm_subflow_check_next$"; then
 			# the server will not signal the address terminating
 			# the MPC subflow
 			chk_add_nr 3 3
+		else
+			chk_add_nr 4 4
 		fi
 	fi
 }