diff mbox series

[net,03/14] mptcp: pm: re-using ID of unused removed subflows

Message ID 20240819-net-mptcp-pm-reusing-id-v1-3-38035d40de5b@kernel.org
State Accepted
Commit edd8b5d868a4d459f3065493001e293901af758d
Headers show
Series mptcp: pm: fix IDs not being reusable | expand

Commit Message

Matthieu Baerts (NGI0) Aug. 19, 2024, 7:45 p.m. UTC
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>
---
 net/mptcp/pm_netlink.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 26f0329e16bb..8b232a210a06 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1469,8 +1469,17 @@  static int mptcp_nl_remove_subflow_and_signal_addr(struct net *net,
 		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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