From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9CC6F140E3C; Thu, 11 Apr 2024 10:42:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712832130; cv=none; b=OkskfZ8qGtaT+Stsp9YR8VX5aC6vDPn6vPlRVoTAwWSbdiqeGzlaDeQq9CMHkhgH22j1RNveiHdXVSwA3Uu6rdAf+hlpooMno1zjW/Q1r6AXS315rP5akbbqhRg4C6hnmWmjXOjV260NZvp+Y/n0nb2Zg219A39EJEWK8WaUziU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712832130; c=relaxed/simple; bh=BqWnsPUgaXbfyT166bwskhR5NXBzeq1RTiB1GSCx96I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QqIMalYJN3vEm4wwtdcURVAf1tqC/iRHMqN3iAU0GUQamb1tAXbn2M36FLGkXfDVHLhhb3+5uxXiNUgKPuK+h9JB/ViDST+sa1UpAh6r2AtScenIpzO33kUOuMs3oRLWl5iVID1/bBcoD+2bRGbPUAeZ4zC0Cce91UYaO5gCuXY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ujk7JEwO; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ujk7JEwO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 23FCEC433F1; Thu, 11 Apr 2024 10:42:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712832130; bh=BqWnsPUgaXbfyT166bwskhR5NXBzeq1RTiB1GSCx96I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ujk7JEwOuIllvXZRUlD7eoYa8rawtUVkG2d8iCMCH8oJryvhCZHE/c2qHzpGAYmfT OSPhh4p9i4IwL05qKN+lUsGzmnn89TZxPXdDhfm0rRVVfh1f99E6eEnpChzLhYN0nB ue0Aaf3BKVU87NsQF/14uf6vpzf0LMsAEO/E3nUE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Christoph Paasch , Davide Caratti , Mat Martineau , "Matthieu Baerts (NGI0)" , Jakub Kicinski Subject: [PATCH 5.10 240/294] mptcp: dont account accept() of non-MPC client as fallback to TCP Date: Thu, 11 Apr 2024 11:56:43 +0200 Message-ID: <20240411095442.800522688@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240411095435.633465671@linuxfoundation.org> References: <20240411095435.633465671@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Davide Caratti commit 7a1b3490f47e88ec4cbde65f1a77a0f4bc972282 upstream. Current MPTCP servers increment MPTcpExtMPCapableFallbackACK when they accept non-MPC connections. As reported by Christoph, this is "surprising" because the counter might become greater than MPTcpExtMPCapableSYNRX. MPTcpExtMPCapableFallbackACK counter's name suggests it should only be incremented when a connection was seen using MPTCP options, then a fallback to TCP has been done. Let's do that by incrementing it when the subflow context of an inbound MPC connection attempt is dropped. Also, update mptcp_connect.sh kselftest, to ensure that the above MIB does not increment in case a pure TCP client connects to a MPTCP server. Fixes: fc518953bc9c ("mptcp: add and use MIB counter infrastructure") Cc: stable@vger.kernel.org Reported-by: Christoph Paasch Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/449 Signed-off-by: Davide Caratti Reviewed-by: Mat Martineau Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://lore.kernel.org/r/20240329-upstream-net-20240329-fallback-mib-v1-1-324a8981da48@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Matthieu Baerts (NGI0) Signed-off-by: Greg Kroah-Hartman --- net/mptcp/protocol.c | 3 --- net/mptcp/subflow.c | 3 +++ 2 files changed, 3 insertions(+), 3 deletions(-) --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2218,9 +2218,6 @@ static struct sock *mptcp_accept(struct __MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK); local_bh_enable(); - } else { - MPTCP_INC_STATS(sock_net(sk), - MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); } out: --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -595,6 +595,9 @@ create_child: if (fallback_is_fatal) goto dispose_child; + if (fallback) + SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); + subflow_drop_ctx(child); goto out; }