From bab6f91c0f7c16f3a66869a89871eeec28bf8a17 Mon Sep 17 00:00:00 2001
From: Jiri Slaby <jslaby@suse.cz>
Date: Apr 20 2023 11:01:03 +0000
Subject: mptcp: use mptcp_schedule_work instead of open-coding it

(bsc#1012628).

---

diff --git a/patches.kernel.org/6.2.12-122-mptcp-use-mptcp_schedule_work-instead-of-open-.patch b/patches.kernel.org/6.2.12-122-mptcp-use-mptcp_schedule_work-instead-of-open-.patch
new file mode 100644
index 0000000..f45457e
--- /dev/null
+++ b/patches.kernel.org/6.2.12-122-mptcp-use-mptcp_schedule_work-instead-of-open-.patch
@@ -0,0 +1,94 @@
+From: Paolo Abeni <pabeni@redhat.com>
+Date: Tue, 11 Apr 2023 22:42:09 +0200
+Subject: [PATCH] mptcp: use mptcp_schedule_work instead of open-coding it
+References: bsc#1012628
+Patch-mainline: 6.2.12
+Git-commit: a5cb752b125766524c921faab1a45cc96065b0a7
+
+commit a5cb752b125766524c921faab1a45cc96065b0a7 upstream.
+
+Beyond reducing code duplication this also avoids scheduling
+the mptcp_worker on a closed socket on some edge scenarios.
+
+The addressed issue is actually older than the blamed commit
+below, but this fix needs it as a pre-requisite.
+
+Fixes: ba8f48f7a4d7 ("mptcp: introduce mptcp_schedule_work")
+Cc: stable@vger.kernel.org
+Signed-off-by: Paolo Abeni <pabeni@redhat.com>
+Reviewed-by: Matthieu Baerts <matthieu.baerts@tessares.net>
+Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
+Signed-off-by: Jakub Kicinski <kuba@kernel.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Signed-off-by: Jiri Slaby <jslaby@suse.cz>
+---
+ net/mptcp/options.c |  5 ++---
+ net/mptcp/subflow.c | 18 ++++++------------
+ 2 files changed, 8 insertions(+), 15 deletions(-)
+
+diff --git a/net/mptcp/options.c b/net/mptcp/options.c
+index 5ded85e2..3872eadb 100644
+--- a/net/mptcp/options.c
++++ b/net/mptcp/options.c
+@@ -1192,9 +1192,8 @@ bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
+ 	 */
+ 	if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) {
+ 		if (mp_opt.data_fin && mp_opt.data_len == 1 &&
+-		    mptcp_update_rcv_data_fin(msk, mp_opt.data_seq, mp_opt.dsn64) &&
+-		    schedule_work(&msk->work))
+-			sock_hold(subflow->conn);
++		    mptcp_update_rcv_data_fin(msk, mp_opt.data_seq, mp_opt.dsn64))
++			mptcp_schedule_work((struct sock *)msk);
+ 
+ 		return true;
+ 	}
+diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
+index 8f6e48e5..dbc02c2c 100644
+--- a/net/mptcp/subflow.c
++++ b/net/mptcp/subflow.c
+@@ -407,9 +407,8 @@ void mptcp_subflow_reset(struct sock *ssk)
+ 
+ 	tcp_send_active_reset(ssk, GFP_ATOMIC);
+ 	tcp_done(ssk);
+-	if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags) &&
+-	    schedule_work(&mptcp_sk(sk)->work))
+-		return; /* worker will put sk for us */
++	if (!test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &mptcp_sk(sk)->flags))
++		mptcp_schedule_work(sk);
+ 
+ 	sock_put(sk);
+ }
+@@ -1117,8 +1116,8 @@ static enum mapping_status get_mapping_status(struct sock *ssk,
+ 				skb_ext_del(skb, SKB_EXT_MPTCP);
+ 				return MAPPING_OK;
+ 			} else {
+-				if (updated && schedule_work(&msk->work))
+-					sock_hold((struct sock *)msk);
++				if (updated)
++					mptcp_schedule_work((struct sock *)msk);
+ 
+ 				return MAPPING_DATA_FIN;
+ 			}
+@@ -1221,17 +1220,12 @@ static void mptcp_subflow_discard_data(struct sock *ssk, struct sk_buff *skb,
+ /* sched mptcp worker to remove the subflow if no more data is pending */
+ static void subflow_sched_work_if_closed(struct mptcp_sock *msk, struct sock *ssk)
+ {
+-	struct sock *sk = (struct sock *)msk;
+-
+ 	if (likely(ssk->sk_state != TCP_CLOSE))
+ 		return;
+ 
+ 	if (skb_queue_empty(&ssk->sk_receive_queue) &&
+-	    !test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags)) {
+-		sock_hold(sk);
+-		if (!schedule_work(&msk->work))
+-			sock_put(sk);
+-	}
++	    !test_and_set_bit(MPTCP_WORK_CLOSE_SUBFLOW, &msk->flags))
++		mptcp_schedule_work((struct sock *)msk);
+ }
+ 
+ static bool subflow_can_fallback(struct mptcp_subflow_context *subflow)
+-- 
+2.35.3
+
diff --git a/series.conf b/series.conf
index d952e77..b3d7a5a 100644
--- a/series.conf
+++ b/series.conf
@@ -2349,6 +2349,7 @@
 	patches.kernel.org/6.2.12-119-cgroup-cpuset-Add-cpuset_can_fork-and-cpuset_c.patch
 	patches.kernel.org/6.2.12-120-drm-amd-pm-correct-SMU13.0.7-pstate-profiling-.patch
 	patches.kernel.org/6.2.12-121-drm-amd-pm-correct-SMU13.0.7-max-shader-clock-.patch
+	patches.kernel.org/6.2.12-122-mptcp-use-mptcp_schedule_work-instead-of-open-.patch
 
 	########################################################
 	# Build fixes that apply to the vanilla kernel too.