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 4E46E46D0BD; Thu, 20 Aug 2026 16:37:46 +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=1787243867; cv=none; b=TiVclBJN+d7CFRYscjydzFcQf7Z+aqanvEInFrhb7HD8GNAYv0ox9SoZS7N2kD36dzR5upTGlxfjhUKwH0eOpBumcHmm+uJ06akQKp+esdPfUQVWCg1sKKueWQbsRrcEKmgPkCdcA9dsplj9o1J4GSSsNe3BxbF2PwvC/YI4WnY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787243867; c=relaxed/simple; bh=OBVgQf20GQalMg/cWXB0vuP8LnkFgExSi5abHQsFPXg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aWB2OKDrUZ43BQZKXJqwFL5biSEm3zKrVlCcmQAuF9bbHyjiscBZT9qgN2nF/5EeUNQsXkFcQhct7Y96AXl+PSNwxJugrQCemOcPU2/WvX5llfze0T5s8WNLDhGz5m8Ilr3o2e3NlJ0GHiP8myBaAwOHe3nhG+iXI0bxGD8lH7s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WEyIx0SL; 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="WEyIx0SL" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC07A1F000E9; Thu, 20 Aug 2026 16:37:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1787243866; bh=4dkEjcglxn3SGyLTebPFrGXis1NhljxYZ1dhVgTufU8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WEyIx0SLleCfY+yx8+eE9y118+iOogF8qcAK6/rsySNu7CgypfXZLGgdPl+4qSvgD 6NjdsrEz7dR9ePwyPWoByQRJONZDAXhUz788cr6T+WPz0gaez9Joj+ToHVVN3Ukc6Q reEtaqlLqEhpwre3fLUxJrUug/vXUNqu3RRLqsAE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chenguang Zhao , "Matthieu Baerts (NGI0)" , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 204/272] mptcp: decrement subflows counter on failed passive join Date: Thu, 20 Aug 2026 16:56:28 +0200 Message-ID: <20260820145237.613154657@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260820145231.229664293@linuxfoundation.org> References: <20260820145231.229664293@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 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chenguang Zhao [ Upstream commit f3ca0ee2cc308e33896536789cbc5f3a12ca7b30 ] mptcp_pm_allow_new_subflow() increments extra_subflows before __mptcp_finish_join() on the passive MP_JOIN path. In case of race conditions, the subflow is dropped without calling mptcp_close_ssk(), so the counter is not rolled back. Call mptcp_pm_close_subflow() when the join completion fails to decrement the subflows counter. Fixes: 10f6d46c943d ("mptcp: fix race between MP_JOIN and close") Cc: stable@vger.kernel.org Signed-off-by: Chenguang Zhao Reviewed-by: Matthieu Baerts (NGI0) Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20260722-net-mptcp-misc-fixes-7-2-rc5-v1-1-6fb595bc86ef@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/mptcp/protocol.c | 1 + 1 file changed, 1 insertion(+) --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -3361,6 +3361,7 @@ bool mptcp_finish_join(struct sock *ssk) mptcp_data_unlock(parent); if (!ret) { + mptcp_pm_close_subflow(msk); err_prohibited: subflow->reset_reason = MPTCP_RST_EPROHIBIT; return false;