The patch below does not apply to the 6.6-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-6.6.y git checkout FETCH_HEAD git cherry-pick -x a13d5aad4dd9a309eecdc33cfd75045bd5f376a3 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024082625-canon-squeeze-24ab@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:

a13d5aad4dd9 ("selftests: mptcp: join: check re-using ID of unused ADD_ADDR") b5e2fb832f48 ("selftests: mptcp: add explicit test case for remove/readd")

thanks,

greg k-h

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

From a13d5aad4dd9a309eecdc33cfd75045bd5f376a3 Mon Sep 17 00:00:00 2001 From: "Matthieu Baerts (NGI0)" matttbe@kernel.org Date: Mon, 19 Aug 2024 21:45:20 +0200 Subject: [PATCH] selftests: mptcp: join: check re-using ID of unused ADD_ADDR

This test extends "delete re-add signal" to validate the previous commit. An extra address is announced by the server, but this address cannot be used by the client. The result is that no subflow will be established to this address.

Later, the server will delete this extra endpoint, and set a new one, with a valid address, but re-using the same ID. Before the previous commit, the server would not have been able to announce this new address.

While at it, extra checks have been added to validate the expected numbers of MPJ, ADD_ADDR and RM_ADDR.

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: b6c08380860b ("mptcp: remove addr and subflow in PM netlink") 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/20240819-net-mptcp-pm-reusing-id-v1-2-38035d40de5b@... 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 9ea6d698e9d3..25077ccf31d2 100755 --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -3601,9 +3601,11 @@ endpoint_tests() # remove and re-add if reset "delete re-add signal" && mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then - pm_nl_set_limits $ns1 1 1 - pm_nl_set_limits $ns2 1 1 + pm_nl_set_limits $ns1 0 2 + pm_nl_set_limits $ns2 2 2 pm_nl_add_endpoint $ns1 10.0.2.1 id 1 flags signal + # 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 test_linkfail=4 speed=20 \ run_tests $ns1 $ns2 10.0.1.1 & local tests_pid=$! @@ -3615,15 +3617,21 @@ endpoint_tests() chk_mptcp_info subflows 1 subflows 1

pm_nl_del_endpoint $ns1 1 10.0.2.1 + pm_nl_del_endpoint $ns1 2 224.0.0.1 sleep 0.5 chk_subflow_nr "after delete" 1 chk_mptcp_info subflows 0 subflows 0

- pm_nl_add_endpoint $ns1 10.0.2.1 flags signal + pm_nl_add_endpoint $ns1 10.0.2.1 id 1 flags signal + pm_nl_add_endpoint $ns1 10.0.3.1 id 2 flags signal wait_mpj $ns2 - chk_subflow_nr "after re-add" 2 - chk_mptcp_info subflows 1 subflows 1 + chk_subflow_nr "after re-add" 3 + chk_mptcp_info subflows 2 subflows 2 mptcp_lib_kill_wait $tests_pid + + chk_join_nr 3 3 3 + chk_add_nr 4 4 + chk_rm_nr 2 1 invert fi

}