This is a note to let you know that I've just added the patch titled mptcp: don't send RST for single subflow to the 5.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mptcp-don-t-send-rst-for-single-subflow.patch and it can be found in the queue-5.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 0a782d12ad419f820fbaf1d637a788097014b5b1 Author: Geliang Tang <geliang.tang@xxxxxxxx> Date: Fri Apr 22 14:55:36 2022 -0700 mptcp: don't send RST for single subflow [ Upstream commit 1761fed2567807f26fbd53032ff622f55978c7a9 ] 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@xxxxxxxx> Signed-off-by: Mat Martineau <mathew.j.martineau@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 7919e259175d..ccae50eba664 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -1221,14 +1221,14 @@ static bool subflow_check_data_avail(struct sock *ssk) /* 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; }