From: Geliang Tang <geliang.tang@suse.com>
Date: Fri, 22 Apr 2022 21:55:36 +0000 (-0700)
Subject: mptcp: don't send RST for single subflow
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=1761fed2567807f26fbd53032ff622f55978c7a9;p=linux.git

mptcp: don't send RST for single subflow

When a bad checksum is detected and a single subflow is in use, don't
send RST + MP_FAIL, send data_ack + MP_FAIL instead.

So invoke tcp_send_active_reset() only when mptcp_has_another_subflow()
is true.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index aba260f547da..f217926f6a9c 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -1206,14 +1206,14 @@ fallback:
 	/* RFC 8684 section 3.7. */
 	if (subflow->send_mp_fail) {
 		if (mptcp_has_another_subflow(ssk)) {
+			ssk->sk_err = EBADMSG;
+			tcp_set_state(ssk, TCP_CLOSE);
+			subflow->reset_transient = 0;
+			subflow->reset_reason = MPTCP_RST_EMIDDLEBOX;
+			tcp_send_active_reset(ssk, GFP_ATOMIC);
 			while ((skb = skb_peek(&ssk->sk_receive_queue)))
 				sk_eat_skb(ssk, skb);
 		}
-		ssk->sk_err = EBADMSG;
-		tcp_set_state(ssk, TCP_CLOSE);
-		subflow->reset_transient = 0;
-		subflow->reset_reason = MPTCP_RST_EMIDDLEBOX;
-		tcp_send_active_reset(ssk, GFP_ATOMIC);
 		WRITE_ONCE(subflow->data_avail, MPTCP_SUBFLOW_NODATA);
 		return true;
 	}