From nobody Tue May 5 11:27:24 2026 Received: from sender4-of-o54.zoho.com (sender4-of-o54.zoho.com [136.143.188.54]) (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 B8B892DECD3 for ; Tue, 28 Apr 2026 07:49:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.54 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777362573; cv=pass; b=WoL6ocntM6ql9BkTf56zyox1q87M881I8v86xzB2Itajw9RqLnvIeCV4g4MIzq0JBPua60Va2IssPah450QtJS5s6twQxdRBU+Vu7dJe1Y5LQHpHmdcSxcUNBc0wJ2mlZJeZYX2JotlPOKxzvuzhrx+WLoEQaSCctjDwH2NhHPo= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777362573; c=relaxed/simple; bh=b6bex6WFRq6aDBcHqJBb0Gov5XokLYyS/cNhOS0NXHM=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=LqytcjJ6zEyS6mwR1MniuR0rNPS4kelNPQbJdhcu2mw0B1xp5NaXUR6sFOQLttV6GFqT3hCAnKih8GfQz14vQca0vJb4c1Z8KzdUUuAXWDDodgXG6+WEqyS31IdlsyE9VVG6raI3U0IUcrV9eYxusqwaL0T/mqgpXMIcElVDNxU= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mpiricsoftware.com; spf=pass smtp.mailfrom=mpiricsoftware.com; dkim=pass (1024-bit key) header.d=mpiricsoftware.com header.i=shardul.b@mpiricsoftware.com header.b=hzu8xVb/; arc=pass smtp.client-ip=136.143.188.54 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=mpiricsoftware.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mpiricsoftware.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=mpiricsoftware.com header.i=shardul.b@mpiricsoftware.com header.b="hzu8xVb/" ARC-Seal: i=1; a=rsa-sha256; t=1777362534; cv=none; d=zohomail.com; s=zohoarc; b=cuiRRhuXgvyhNhpGLtOdWmNoFwm2Dmi0eqEQvgOuNZ9lcdhn6jTHNHmDR7l5MrWhC3wXhBLnjdjQtiWMMwKDEhTmRW6HjsI703VujIm9YAnOhkU4uNdK99q00RR8VthwGUr04g0poWMan40cPSFqEeM96DOuvg5GyxNkgYnm++8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1777362534; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=8X1D7Re0OwwPN71om672yr0MR9k9nhXm05Hpv//9k/s=; b=G5h0GWw+Nna8AtrL792QhtQZjVlYkn9ADrp9UoXSGXy2aBzT2pN76TYBSef099jBonAq0hFPyLOLWF7CR9Sr90pLDS62vATV+7JSUpssUkuoMLW0VCezUG96w/s5lC31aP2TJRxhWy7HRdq+BYOLKTItaIZoSMyRGwOX1wdlGzQ= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=mpiricsoftware.com; spf=pass smtp.mailfrom=shardul.b@mpiricsoftware.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1777362534; s=mpiric; d=mpiricsoftware.com; i=shardul.b@mpiricsoftware.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-Id:Message-Id:MIME-Version:Content-Transfer-Encoding:Reply-To; bh=8X1D7Re0OwwPN71om672yr0MR9k9nhXm05Hpv//9k/s=; b=hzu8xVb/iBKeOLjdRnqtE3IIGfbMULGl/OEPq3wx5bNQagxP6ksaPlx9hA5vXAgU D03/3hPkGqb+fJgQM9kHlwoR7bEcjSsj6uE+BKcb7PPZ8Et2zuovupd1sYMzswN8TVr xk59usRzyEAnZsyr6RRdysWGl1tW7WfhHoqcTS3c= Received: by mx.zohomail.com with SMTPS id 1777362531931130.09521301305165; Tue, 28 Apr 2026 00:48:51 -0700 (PDT) From: Shardul Bankar To: mptcp@lists.linux.dev Cc: matttbe@kernel.org, martineau@kernel.org, geliang@kernel.org, pabeni@redhat.com, janak@mpiric.us, kalpan.jani@mpiricsoftware.com, shardulsb08@gmail.com, Shardul Bankar , stable@vger.kernel.org Subject: [PATCH mptcp-net] mptcp: use MPJoinSynAckHMacFailure for SynAck HMAC failure Date: Tue, 28 Apr 2026 13:18:44 +0530 Message-Id: <20260428074844.1746594-1-shardul.b@mpiricsoftware.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Content-Type: text/plain; charset="utf-8" In subflow_finish_connect(), HMAC validation of the server's HMAC in SYN/ACK + MP_JOIN increments MPTCP_MIB_JOINACKMAC ("HMAC was wrong on ACK + MP_JOIN") on failure. The function processes the SYN/ACK, not the ACK; the matching MPTCP_MIB_JOINSYNACKMAC counter ("HMAC was wrong on SYN/ACK + MP_JOIN") exists but is not incremented anywhere in the tree. The mirror site on the server, subflow_syn_recv_sock(), already uses JOINACKMAC correctly for ACK HMAC failure. Use JOINSYNACKMAC at the SYN/ACK validation site so each counter reflects the packet whose HMAC actually failed. Suggested-by: Matthieu Baerts (NGI0) Fixes: 3eccc998b50b ("mptcp: increment MIB counters in a few places") Cc: stable@vger.kernel.org Signed-off-by: Shardul Bankar Reviewed-by: Matthieu Baerts (NGI0) --- net/mptcp/subflow.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index e2cb9d23e4a0..bda6862264ca 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -581,7 +581,7 @@ static void subflow_finish_connect(struct sock *sk, con= st struct sk_buff *skb) subflow->backup); =20 if (!subflow_thmac_valid(subflow)) { - MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINACKMAC); + MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKMAC); subflow->reset_reason =3D MPTCP_RST_EMPTCP; goto do_reset; } --=20 2.34.1