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 96BCB7CF17; Mon, 8 Apr 2024 13:26:50 +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=1712582810; cv=none; b=ADSfaNcxlK27ET5vDPF1mQYiCe+y0kxk1l5inoY4HlrzphNG9VN7J3rQ0c31YMuUysExHVg0G4/BarbD92vh4RtzRbt3LyhgNsqYjtcRk9PnquIVc0qgo7sVC4x7Yogby0+DHGBTgaworVPhvjoTc/cU47PT9b4YyzqdmENrwnQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712582810; c=relaxed/simple; bh=sIROaMLBXl9ovwjgcoYStBNcELbursA65VbT2Il6PJ8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Opa2I2iaHowlt7ACvHhtnp9vnPPFuUicU1g9OIZ05w4hRvh+Ar3Oil+B8Le9PyHU1HI5j5kndaOZ+yN1XTXkRUBAspLv5OPdiP2oa/li+4LCyvtfMzaHNqVNAbXDK/VCdSzPAySFGtvOv/+epLxtIkbXogzJmMo467GVzMbn7fI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=scrEmhAE; 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="scrEmhAE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1D923C43390; Mon, 8 Apr 2024 13:26:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712582810; bh=sIROaMLBXl9ovwjgcoYStBNcELbursA65VbT2Il6PJ8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=scrEmhAEWHOHonFRUZrJ538mAs8A9CIVTXITX5r1F7l8ZWKEh16jDUVotzF9q++9b H0ak+r50OqOan6whziXYpBeNoD/SDtoXwCT/L05dEzvWFHYvfvIsAh4JU7oT5/Xi3j wHukkQRs3iqR4aP5tNOCPAl4TbKDzrUyAf4q+YVw= 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 6.1 135/138] mptcp: dont account accept() of non-MPC client as fallback to TCP Date: Mon, 8 Apr 2024 14:59:09 +0200 Message-ID: <20240408125300.428044615@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125256.218368873@linuxfoundation.org> References: <20240408125256.218368873@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-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 | 2 ++ tools/testing/selftests/net/mptcp/mptcp_connect.sh | 7 +++++++ 3 files changed, 9 insertions(+), 3 deletions(-) --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -3349,9 +3349,6 @@ static struct sock *mptcp_accept(struct newsk = new_mptcp_sock; MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_MPCAPABLEPASSIVEACK); - } else { - MPTCP_INC_STATS(sock_net(sk), - MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); } out: --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -816,6 +816,8 @@ dispose_child: return child; fallback: + if (fallback) + SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK); mptcp_subflow_drop_ctx(child); return child; } --- a/tools/testing/selftests/net/mptcp/mptcp_connect.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_connect.sh @@ -439,6 +439,7 @@ do_transfer() local stat_cookierx_last=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv") local stat_csum_err_s=$(get_mib_counter "${listener_ns}" "MPTcpExtDataCsumErr") local stat_csum_err_c=$(get_mib_counter "${connector_ns}" "MPTcpExtDataCsumErr") + local stat_tcpfb_last_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK") timeout ${timeout_test} \ ip netns exec ${listener_ns} \ @@ -504,6 +505,7 @@ do_transfer() local stat_cookietx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesSent") local stat_cookierx_now=$(get_mib_counter "${listener_ns}" "TcpExtSyncookiesRecv") local stat_ooo_now=$(get_mib_counter "${listener_ns}" "TcpExtTCPOFOQueue") + local stat_tcpfb_now_l=$(get_mib_counter "${listener_ns}" "MPTcpExtMPCapableFallbackACK") expect_synrx=$((stat_synrx_last_l)) expect_ackrx=$((stat_ackrx_last_l)) @@ -548,6 +550,11 @@ do_transfer() fi fi + if [ ${stat_ooo_now} -eq 0 ] && [ ${stat_tcpfb_last_l} -ne ${stat_tcpfb_now_l} ]; then + printf "[ FAIL ]\nunexpected fallback to TCP" + rets=1 + fi + if [ $retc -eq 0 ] && [ $rets -eq 0 ]; then printf "[ OK ]" fi