FAILED: patch "[PATCH] selftests: mptcp: join: check removing ID 0 endpoint" failed to apply to 6.1-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.1-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y
git checkout FETCH_HEAD
git cherry-pick -x 5f94b08c001290acda94d9d8868075590931c198
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2024083009-escapable-arguable-125f@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^..

Possible dependencies:

5f94b08c0012 ("selftests: mptcp: join: check removing ID 0 endpoint")
65fb58afa341 ("selftests: mptcp: join: check re-using ID of closed subflow")
40061817d95b ("selftests: mptcp: join: fix dev in check_endpoint")
04b57c9e096a ("selftests: mptcp: join: stop transfer when check is done (part 2)")
b9fb176081fb ("selftests: mptcp: userspace pm send RM_ADDR for ID 0")
e3b47e460b4b ("selftests: mptcp: userspace pm remove initial subflow")
03668c65d153 ("selftests: mptcp: join: rework detailed report")
7f117cd37c61 ("selftests: mptcp: join: format subtests results in TAP")
e571fb09c893 ("selftests: mptcp: add speed env var")
4aadde088a58 ("selftests: mptcp: add fullmesh env var")
080b7f5733fd ("selftests: mptcp: add fastclose env var")
662aa22d7dcd ("selftests: mptcp: set all env vars as local ones")
9e9d176df8e9 ("selftests: mptcp: add pm_nl_set_endpoint helper")
1534f87ee0dc ("selftests: mptcp: drop sflags parameter")
595ef566a2ef ("selftests: mptcp: drop addr_nr_ns1/2 parameters")
0c93af1f8907 ("selftests: mptcp: drop test_linkfail parameter")
be7e9786c915 ("selftests: mptcp: set FAILING_LINKS in run_tests")
d7ced753aa85 ("selftests: mptcp: check subflow and addr infos")
4369c198e599 ("selftests: mptcp: test userspace pm out of transfer")
00079f18c24f ("selftests: mptcp: join: skip check if MIB counter not supported (part 2)")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5f94b08c001290acda94d9d8868075590931c198 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <matttbe@kernel.org>
Date: Wed, 28 Aug 2024 08:14:26 +0200
Subject: [PATCH] selftests: mptcp: join: check removing ID 0 endpoint

Removing the endpoint linked to the initial subflow should trigger a
RM_ADDR for the right ID, and the removal of the subflow. That's what is
now being verified in the "delete and re-add" test.

Note that removing the initial subflow will not decrement the 'subflows'
counters, which corresponds to the *additional* subflows. On the other
hand, when the same endpoint is re-added, it will increment this
counter, as it will be seen as an additional subflow this time.

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: 3ad14f54bd74 ("mptcp: more accurate MPC endpoint tracking")
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>

diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh
index 264040a760c6..8b4529ff15e5 100755
--- a/tools/testing/selftests/net/mptcp/mptcp_join.sh
+++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh
@@ -3572,8 +3572,9 @@ endpoint_tests()
 
 	if reset_with_tcp_filter "delete and re-add" ns2 10.0.3.2 REJECT OUTPUT &&
 	   mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then
-		pm_nl_set_limits $ns1 0 2
-		pm_nl_set_limits $ns2 0 2
+		pm_nl_set_limits $ns1 0 3
+		pm_nl_set_limits $ns2 0 3
+		pm_nl_add_endpoint $ns2 10.0.1.2 id 1 dev ns2eth1 flags subflow
 		pm_nl_add_endpoint $ns2 10.0.2.2 id 2 dev ns2eth2 flags subflow
 		test_linkfail=4 speed=20 \
 			run_tests $ns1 $ns2 10.0.1.1 &
@@ -3582,17 +3583,17 @@ endpoint_tests()
 		wait_mpj $ns2
 		pm_nl_check_endpoint "creation" \
 			$ns2 10.0.2.2 id 2 flags subflow dev ns2eth2
-		chk_subflow_nr "before delete" 2
+		chk_subflow_nr "before delete id 2" 2
 		chk_mptcp_info subflows 1 subflows 1
 
 		pm_nl_del_endpoint $ns2 2 10.0.2.2
 		sleep 0.5
-		chk_subflow_nr "after delete" 1
+		chk_subflow_nr "after delete id 2" 1
 		chk_mptcp_info subflows 0 subflows 0
 
 		pm_nl_add_endpoint $ns2 10.0.2.2 id 2 dev ns2eth2 flags subflow
 		wait_mpj $ns2
-		chk_subflow_nr "after re-add" 2
+		chk_subflow_nr "after re-add id 2" 2
 		chk_mptcp_info subflows 1 subflows 1
 
 		pm_nl_add_endpoint $ns2 10.0.3.2 id 3 flags subflow
@@ -3607,10 +3608,20 @@ endpoint_tests()
 		chk_subflow_nr "after no reject" 3
 		chk_mptcp_info subflows 2 subflows 2
 
+		pm_nl_del_endpoint $ns2 1 10.0.1.2
+		sleep 0.5
+		chk_subflow_nr "after delete id 0" 2
+		chk_mptcp_info subflows 2 subflows 2 # only decr for additional sf
+
+		pm_nl_add_endpoint $ns2 10.0.1.2 id 1 dev ns2eth1 flags subflow
+		wait_mpj $ns2
+		chk_subflow_nr "after re-add id 0" 3
+		chk_mptcp_info subflows 3 subflows 3
+
 		mptcp_lib_kill_wait $tests_pid
 
-		chk_join_nr 3 3 3
-		chk_rm_nr 1 1
+		chk_join_nr 4 4 4
+		chk_rm_nr 2 2
 	fi
 
 	# remove and re-add