FAILED: patch "[PATCH] mptcp: fix snd_wnd initialization for passive socket" failed to apply to 5.15-stable tree

The patch below does not apply to the 5.15-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-5.15.y
git checkout FETCH_HEAD
git cherry-pick -x adf1bb78dab55e36d4d557aa2fb446ebcfe9e5ce
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2024030417-jaws-icky-a0f2@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

adf1bb78dab5 ("mptcp: fix snd_wnd initialization for passive socket")

thanks,

greg k-h

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

From adf1bb78dab55e36d4d557aa2fb446ebcfe9e5ce Mon Sep 17 00:00:00 2001
From: Paolo Abeni <[email protected]>
Date: Fri, 23 Feb 2024 17:14:15 +0100
Subject: [PATCH] mptcp: fix snd_wnd initialization for passive socket

Such value should be inherited from the first subflow, but passive sockets always used 'rsk_rcv_wnd'.

index 442fa7d9b57a..2c8f931c6d5b 100644
@@ -3211,7 +3211,7 @@ struct sock *mptcp_sk_clone_init(const struct sock *sk,
 	msk->write_seq = subflow_req->idsn + 1;
 	msk->snd_nxt = msk->write_seq;
 	msk->snd_una = msk->write_seq;
-	msk->wnd_end = msk->snd_nxt + req->rsk_rcv_wnd;
+	msk->wnd_end = msk->snd_nxt + tcp_sk(ssk)->snd_wnd;
 	msk->setsockopt_seq = mptcp_sk(sk)->setsockopt_seq;
 	mptcp_init_sched(msk, mptcp_sk(sk)->sched);
 

Hi Greg,

(...)

This commit depends on commit 7e8b88ec35ee ("mptcp: consolidate passive msk socket initialization") which has apparently not been backported to v5.15 due to a too long list of dependences.

Even if it would be better to have this fix, I don't think it is worth having it in v5.15.

Cheers,
Matt

Sponsored by the NGI0 Core fund.

Thanks for looking into this and letting us know.

greg k-h