6.6-stable review patch. If anyone has any objections, please let me know.
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From: Matthieu Baerts (NGI0) matttbe@kernel.org
commit edd8b5d868a4d459f3065493001e293901af758d upstream.
If no subflow is attached to the 'subflow' endpoint that is being removed, the addr ID will not be marked as available again.
Mark the linked ID as available when removing the 'subflow' endpoint if no subflow is attached to it.
While at it, the local_addr_used counter is decremented if the ID was marked as being used to reflect the reality, but also to allow adding new endpoints after that.
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-v1-3-38035d40de5b@... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/mptcp/pm_netlink.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)
--- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1500,8 +1500,17 @@ static int mptcp_nl_remove_subflow_and_s remove_subflow = lookup_subflow_by_saddr(&msk->conn_list, addr); mptcp_pm_remove_anno_addr(msk, addr, remove_subflow && !(entry->flags & MPTCP_PM_ADDR_FLAG_IMPLICIT)); - if (remove_subflow) + + if (remove_subflow) { mptcp_pm_remove_subflow(msk, &list); + } else if (entry->flags & MPTCP_PM_ADDR_FLAG_SUBFLOW) { + /* If the subflow has been used, but now closed */ + spin_lock_bh(&msk->pm.lock); + if (!__test_and_set_bit(entry->addr.id, msk->pm.id_avail_bitmap)) + msk->pm.local_addr_used--; + spin_unlock_bh(&msk->pm.lock); + } + release_sock(sk);
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