FAILED: patch "[PATCH] mptcp: pm: reuse ID 0 after delete and re-add" failed to apply to 6.12-stable tree

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 8b8ed1b429f8fa7ebd5632555e7b047bc0620075
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024083041-irate-headless-590c@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8b8ed1b429f8fa7ebd5632555e7b047bc0620075 Mon Sep 17 00:00:00 2001
From: "Matthieu Baerts (NGI0)" <[email protected]>
Date: Wed, 28 Aug 2024 08:14:24 +0200
Subject: [PATCH] mptcp: pm: reuse ID 0 after delete and re-add

When the endpoint used by the initial subflow is removed and re-added later, the PM has to force the ID 0, it is a special case imposed by the MPTCP specs.

Note that the endpoint should then need to be re-added reusing the same ID.

index 8d2f97854c64..ec45ab4c66ab 100644
@@ -585,6 +585,11 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 
 		__clear_bit(local.addr.id, msk->pm.id_avail_bitmap);
 		msk->pm.add_addr_signaled++;
+
+		/* Special case for ID0: set the correct ID */
+		if (local.addr.id == msk->mpc_endpoint_id)
+			local.addr.id = 0;
+
 		mptcp_pm_announce_addr(msk, &local.addr, false);
 		mptcp_pm_nl_addr_send_ack(msk);
 

@@ -609,6 +614,11 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 
 		msk->pm.local_addr_used++;
 		__clear_bit(local.addr.id, msk->pm.id_avail_bitmap);
+
+		/* Special case for ID0: set the correct ID */
+		if (local.addr.id == msk->mpc_endpoint_id)
+			local.addr.id = 0;
+
 		nr = fill_remote_addresses_vec(msk, &local.addr, fullmesh, addrs);
 		if (nr == 0)
 			continue;

Hi Greg,

v6.12? Are you back from the future? :)

Cheers,
Matt

Sponsored by the NGI0 Core fund.

Hah, you noticed this, sorry. Slip of the finger :)