Here is a new batch of fixes for the MPTCP in-kernel path-manager: Patch 1 ensures the address ID is set to 0 when the path-manager sends an ADD_ADDR for the address of the initial subflow. The same fix is applied when a new subflow is created re-using this special address. A fix for v6.0. Patch 2 is similar, but for the case where an endpoint is removed: if this endpoint was used for the initial address, it is important to send a RM_ADDR with this ID set to 0, and look for existing subflows with the ID set to 0. A fix for v6.0 as well. Patch 3 validates the two previous patches. Patch 4 makes the PM selecting an "active" path to send an address notification in an ACK, instead of taking the first path in the list. A fix for v5.11. Patch 5 fixes skipping the establishment of a new subflow if a previous subflow using the same pair of addresses is being closed. A fix for v5.13. Patch 6 resets the ID linked to the initial subflow when the linked endpoint is re-added, possibly with a different ID. A fix for v6.0. Patch 7 validates the three previous patches. Patch 8 is a small fix for the MPTCP Join selftest, when being used with older subflows not supporting all MIB counters. A fix for a commit introduced in v6.4, but backported up to v5.10. Patch 9 avoids the PM to try to close the initial subflow multiple times, and increment counters while nothing happened. A fix for v5.10. Patch 10 stops incrementing local_addr_used and add_addr_accepted counters when dealing with the address ID 0, because these counters are not taking into account the initial subflow, and are then not decremented when the linked addresses are removed. A fix for v6.0. Patch 11 validates the previous patch. Patch 12 avoids the PM to send multiple SUB_CLOSED events for the initial subflow. A fix for v5.12. Patch 13 validates the previous patch. Patch 14 stops treating the ADD_ADDR 0 as a new address, and accepts it in order to re-create the initial subflow if it has been closed, even if the limit for *new* addresses -- not taking into account the address of the initial subflow -- has been reached. A fix for v5.10. Patch 15 validates the previous patch. Signed-off-by: Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx> --- Changes in v2: - Patches 11,15/15: allow the connection to run for longer, should fix the issue seen on the Netdev CI, with a debug kconfig. - Link to v1: https://lore.kernel.org/r/20240826-net-mptcp-more-pm-fix-v1-0-8cd6c87d1d6d@xxxxxxxxxx --- Matthieu Baerts (NGI0) (15): mptcp: pm: reuse ID 0 after delete and re-add mptcp: pm: fix RM_ADDR ID for the initial subflow selftests: mptcp: join: check removing ID 0 endpoint mptcp: pm: send ACK on an active subflow mptcp: pm: skip connecting to already established sf mptcp: pm: reset MPC endp ID when re-added selftests: mptcp: join: check re-adding init endp with != id selftests: mptcp: join: no extra msg if no counter mptcp: pm: do not remove already closed subflows mptcp: pm: fix ID 0 endp usage after multiple re-creations selftests: mptcp: join: check re-re-adding ID 0 endp mptcp: avoid duplicated SUB_CLOSED events selftests: mptcp: join: validate event numbers mptcp: pm: ADD_ADDR 0 is not a new address selftests: mptcp: join: check re-re-adding ID 0 signal net/mptcp/pm.c | 4 +- net/mptcp/pm_netlink.c | 87 ++++++++++---- net/mptcp/protocol.c | 6 + net/mptcp/protocol.h | 5 +- tools/testing/selftests/net/mptcp/mptcp_join.sh | 153 ++++++++++++++++++++---- tools/testing/selftests/net/mptcp/mptcp_lib.sh | 4 + 6 files changed, 209 insertions(+), 50 deletions(-) --- base-commit: 3a0504d54b3b57f0d7bf3d9184a00c9f8887f6d7 change-id: 20240826-net-mptcp-more-pm-fix-ffa61a36f817 Best regards, -- Matthieu Baerts (NGI0) <matttbe@xxxxxxxxxx>