FAILED: patch "[PATCH] selftests: mptcp: join: test for flush/re-add endpoints" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-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 <[email protected]>.

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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x e06959e9eebdfea4654390f53b65cff57691872e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024082619-chair-irritable-03aa@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

e06959e9eebd ("selftests: mptcp: join: test for flush/re-add endpoints") b5e2fb832f48 ("selftests: mptcp: add explicit test case for remove/readd") ae7bd9ccecc3 ("selftests: mptcp: join: option to execute specific tests") e59300ce3ff8 ("selftests: mptcp: join: reset failing links") 3afd0280e7d3 ("selftests: mptcp: join: define tests groups once") 3c082695e78b ("selftests: mptcp: drop msg argument of chk_csum_nr") 69c6ce7b6eca ("selftests: mptcp: add implicit endpoint test case") d045b9eb95a9 ("mptcp: introduce implicit endpoints")
6fa0174a7c86 ("mptcp: more careful RM_ADDR generation") f98c2bca7b2b ("selftests: mptcp: Rename wait function") 826d7bdca833 ("selftests: mptcp: join: allow running -cCi") 7d9bf018f907 ("selftests: mptcp: update output info of chk_rm_nr") 26516e10c433 ("selftests: mptcp: add more arguments for chk_join_nr") 8117dac3e7c3 ("selftests: mptcp: add invert check in check_transfer") 01542c9bf9ab ("selftests: mptcp: add fastclose testcase") cbfafac4cf8f ("selftests: mptcp: add extra_args in do_transfer") 922fd2b39e5a ("selftests: mptcp: add the MP_RST mibs check") e8e947ef50f6 ("selftests: mptcp: add the MP_FASTCLOSE mibs check") 9a0a93672c14 ("selftests: mptcp: adjust output alignment for more tests") aaa25a2fa796 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")

thanks,

greg k-h

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

From e06959e9eebdfea4654390f53b65cff57691872e Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <[email protected]>
Date: Mon, 19 Aug 2024 21:45:24 +0200
Subject: [PATCH] selftests: mptcp: join: test for flush/re-add endpoints

After having flushed endpoints that didn't cause the creation of new subflows, it is important to check endpoints can be re-created, re-using previously used IDs.

Before the previous commit, the client would not have been able to re-create the subflow that was previously rejected.

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.

index fbb0174145ad..f609c02c6123 100755
@@ -3651,6 +3651,36 @@ endpoint_tests()
 		chk_rm_nr 2 1 invert
 	fi
 
+	# flush and re-add
+	if reset_with_tcp_filter "flush 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 1 2
+		# 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 $ns2 10.0.3.2 id 3 flags subflow
+		test_linkfail=4 speed=20 \
+			run_tests $ns1 $ns2 10.0.1.1 &
+		local tests_pid=$!
+
+		wait_attempt_fail $ns2
+		chk_subflow_nr "before flush" 1
+		chk_mptcp_info subflows 0 subflows 0
+
+		pm_nl_flush_endpoint $ns2
+		pm_nl_flush_endpoint $ns1
+		wait_rm_addr $ns2 0
+		ip netns exec "${ns2}" ${iptables} -D OUTPUT -s "10.0.3.2" -p tcp -j REJECT
+		pm_nl_add_endpoint $ns2 10.0.3.2 id 3 flags subflow
+		wait_mpj $ns2
+		pm_nl_add_endpoint $ns1 10.0.3.1 id 2 flags signal
+		wait_mpj $ns2
+		mptcp_lib_kill_wait $tests_pid
+
+		chk_join_nr 2 2 2
+		chk_add_nr 2 2
+		chk_rm_nr 1 0 invert
+	fi
 }
 
 # [$1: error message]

Hi Greg,

Thank you for the notification!

(...)

Similar to my previous message mentioning that the 'Fixes' tag here is pointing at the issue in the code, but the test file cannot easily be patched to validate the issue: no need to worry about that one for v5.15.

Cheers,
Matt

Sponsored by the NGI0 Core fund.