Commit e461e8a7 authored by Matthieu Baerts (NGI0)'s avatar Matthieu Baerts (NGI0) Committed by Jakub Kicinski
Browse files

mptcp: pm: in kernel: only use fullmesh endp if any 



Our documentation is saying that the in-kernel PM is only using fullmesh
endpoints to establish subflows to announced addresses when at least one
endpoint has a fullmesh flag. But this was not totally correct: only
fullmesh endpoints were used if at least one endpoint *from the same
address family as the received ADD_ADDR* has the fullmesh flag.

This is confusing, and it seems clearer not to have differences
depending on the address family.

So, now, when at least one MPTCP endpoint has a fullmesh flag, the local
addresses are picked from all fullmesh endpoints, which might be 0 if
there are no endpoints for the correct address family.

One selftest needs to be adapted for this behaviour change.

Reviewed-by: default avatarGeliang Tang <geliang@kernel.org>
Signed-off-by: default avatarMatthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251101-net-next-mptcp-fm-endp-nb-bind-v1-2-b4166772d6bb@kernel.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent f88191c7

net/mptcp/pm_kernel.c

+3 −7
Original line number Diff line number Diff line
@@ -609,15 +609,11 @@ fill_local_addresses_vec(struct mptcp_sock *msk, struct mptcp_addr_info *remote, 
			 struct mptcp_pm_local *locals)

{

	bool c_flag_case = remote->id && mptcp_pm_add_addr_c_flag_case(msk);

	int i;



	/* If there is at least one MPTCP endpoint with a fullmesh flag */

	if (mptcp_pm_get_endp_fullmesh_max(msk)) {

		i = fill_local_addresses_vec_fullmesh(msk, remote, locals,

	if (mptcp_pm_get_endp_fullmesh_max(msk))

		return fill_local_addresses_vec_fullmesh(msk, remote, locals,

							 c_flag_case);

		if (i)

			return i;

	}



	/* If there is at least one MPTCP endpoint with a laminar flag */

	if (mptcp_pm_get_endp_laminar_max(msk))

tools/testing/selftests/net/mptcp/mptcp_join.sh

+5 −1
Original line number Diff line number Diff line
@@ -2952,8 +2952,12 @@ mixed_tests() 
		pm_nl_add_endpoint $ns1 10.0.1.1 flags signal

		speed=slow \

			run_tests $ns1 $ns2 dead:beef:2::1

		if mptcp_lib_kallsyms_has "mptcp_pm_get_endp_fullmesh_max$"; then

			chk_join_nr 0 0 0

		else

			chk_join_nr 1 1 1

		fi

	fi



	# fullmesh still tries to create all the possibly subflows with

	# matching family