From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 9DFE332D42B; Sat, 30 May 2026 17:04:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780160664; cv=none; b=ts5eOtrZqaMoV0eShrlVSwRYZXer/e9/kH0eRc6cTiNZoxPH+BMKt0OxfaVB+LQFekLpJaZCrpJ6DKwhIVEX0nIU3pXuz7hnzkAAFr5tEyUEdfMKCHt8KrNLx+ExsBGPscWAuEWTL98u5Zrw7+Oy8vJL652Sz42Voj1EFS4l6P0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780160664; c=relaxed/simple; bh=vF/4c7SeRVfHkV6FXp0mRZNK1iHn6jZ5NT3YZSeQ7Kg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=QuGEZ3x6AkYcI2SPrp65Mb1HCoxeTO2MNyRgovtkwFfpVI/gVocyBk7HqtLIG4IWN+p1F1WFXn0zjwmFAD70XuJOb0+QxAqoOEE7GWoGaoI5eI8JiGYMN7/HFDma06X5tw9QYcS8mHWKmAcdHsuCazRLE1a+3pbtdsZMhYMWzmo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=HusEuBVC; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="HusEuBVC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D39D51F00893; Sat, 30 May 2026 17:04:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780160663; bh=qZhXLw1uXH7n0pHImRoT48gWAQ5ah7zGCy9jc1O96Mc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=HusEuBVCr4f4TzZDA8r584Vq+NhEW/yrQff9PJs+e0DoFxmkH8t9nq2JPFU8gXJvs AWNZDKKy20SqHur331qarCE7hzED5FwpmBqAPwo6B2dHiMs9qf6mAwQUh3iXSeBmav fxEjj0K56MXeLKv5hAJwx8DHpy67qJg1+lIo5XsY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Matthieu Baerts (NGI0)" , Shardul Bankar , Jakub Kicinski Subject: [PATCH 6.1 372/969] mptcp: use MPTCP_RST_EMPTCP for ACK HMAC validation failure Date: Sat, 30 May 2026 17:58:16 +0200 Message-ID: <20260530160310.587893575@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160300.485627683@linuxfoundation.org> References: <20260530160300.485627683@linuxfoundation.org> User-Agent: quilt/0.69 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: Shardul Bankar commit a6da02d4c00fdda2417e42ad2b762a9209e6cc49 upstream. When HMAC validation fails on a received ACK + MP_JOIN in subflow_syn_recv_sock(), the subflow is reset with reason MPTCP_RST_EPROHIBIT ("Administratively prohibited"). This is incorrect: HMAC validation failure is an MPTCP protocol-level error, not an administrative policy denial. The mirror site on the client, in subflow_finish_connect(), already uses MPTCP_RST_EMPTCP ("MPTCP-specific error") for the same kind of HMAC failure on the SYN/ACK + MP_JOIN. Use the same reason on the server side for symmetry and accuracy. Suggested-by: Matthieu Baerts (NGI0) Fixes: 443041deb5ef ("mptcp: fix NULL pointer in can_accept_new_subflow") Cc: stable@vger.kernel.org Signed-off-by: Shardul Bankar Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260501-net-mptcp-misc-fixes-7-1-rc3-v1-2-b70118df778e@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/mptcp/subflow.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -796,7 +796,7 @@ create_child: if (!subflow_hmac_valid(req, &mp_opt)) { SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_JOINACKMAC); - subflow_add_reset_reason(skb, MPTCP_RST_EPROHIBIT); + subflow_add_reset_reason(skb, MPTCP_RST_EMPTCP); goto dispose_child; }