From: "Matthieu Baerts (NGI0)" <matttbe@xxxxxxxxxx> commit 1c2326fcae4f0c5de8ad0d734ced43a8e5f17dac upstream. The initial subflow has a special local ID: 0. It is specific per connection. When a global endpoint is deleted and re-added later, it can have a different ID, but the kernel should still use the ID 0 if it corresponds to the initial address. This test validates this behaviour: the endpoint linked to the initial subflow is removed, and re-added with a different ID. 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@xxxxxxxxxxxxxxx Reviewed-by: Mat Martineau <martineau@xxxxxxxxxx> Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx> [ Conflicts in mptcp_join.sh, because the helpers are different in this version: - run_tests has been modified a few times to reduce the number of positional parameters - no chk_mptcp_info helper - chk_subflow_nr taking an extra parameter - kill_tests_wait instead of mptcp_lib_kill_wait ] Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/net/mptcp/mptcp_join.sh | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -3243,11 +3243,12 @@ userspace_tests() # remove and re-add if reset "delete re-add signal" && mptcp_lib_kallsyms_has "subflow_rebuild_header$"; then - pm_nl_set_limits $ns1 0 2 - pm_nl_set_limits $ns2 2 2 + pm_nl_set_limits $ns1 0 3 + pm_nl_set_limits $ns2 3 3 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 + pm_nl_add_endpoint $ns1 10.0.1.1 id 42 flags signal run_tests $ns1 $ns2 10.0.1.1 4 0 0 speed_20 2>/dev/null & local tests_pid=$! @@ -3263,11 +3264,19 @@ userspace_tests() pm_nl_add_endpoint $ns1 10.0.3.1 id 2 flags signal wait_mpj $ns2 chk_subflow_nr "" "after re-add" 3 + + pm_nl_del_endpoint $ns1 42 10.0.1.1 + sleep 0.5 + chk_subflow_nr "" "after delete ID 0" 2 + + pm_nl_add_endpoint $ns1 10.0.1.1 id 99 flags signal + wait_mpj $ns2 + chk_subflow_nr "" "after re-add" 3 kill_tests_wait - chk_join_nr 3 3 3 - chk_add_nr 4 4 - chk_rm_nr 2 1 invert + chk_join_nr 4 4 4 + chk_add_nr 5 5 + chk_rm_nr 3 2 invert fi } Patches currently in stable-queue which might be from matttbe@xxxxxxxxxx are queue-6.1/mptcp-pm-fix-rm_addr-id-for-the-initial-subflow.patch queue-6.1/selftests-mptcp-join-validate-fullmesh-endp-on-1st-sf.patch queue-6.1/mptcp-pm-fix-id-0-endp-usage-after-multiple-re-creations.patch queue-6.1/mptcp-make-pm_remove_addrs_and_subflows-static.patch queue-6.1/mptcp-pm-avoid-possible-uaf-when-selecting-endp.patch queue-6.1/mptcp-pm-reuse-id-0-after-delete-and-re-add.patch queue-6.1/selftests-mptcp-join-check-re-adding-init-endp-with-id.patch queue-6.1/selftests-mptcp-join-test-for-flush-re-add-endpoints.patch queue-6.1/selftests-mptcp-add-explicit-test-case-for-remove-re.patch queue-6.1/selftests-mptcp-add-explicit-test-case-for-remove-readd.patch queue-6.1/selftests-mptcp-join-check-re-adding-init-endp-with-.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-closed-subflow.patch queue-6.1/mptcp-pm-fullmesh-select-the-right-id-later.patch queue-6.1/mptcp-pr_debug-add-missing-n-at-the-end.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-unused-add.patch queue-6.1/selftests-mptcp-join-check-re-using-id-of-unused-add_addr.patch