From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 37C27C433EF for ; Tue, 10 May 2022 13:14:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242514AbiEJNRv (ORCPT ); Tue, 10 May 2022 09:17:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242360AbiEJNQQ (ORCPT ); Tue, 10 May 2022 09:16:16 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 741573ED13; Tue, 10 May 2022 06:12:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 3850D61574; Tue, 10 May 2022 13:12:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4855BC385C2; Tue, 10 May 2022 13:12:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1652188331; bh=JRE8OAckK6Z2/pZaQdU2BPmNB27yYOJnPnYlHynw71Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZhjFuPD0LJiz8ipPJInDDSnvRb2fSJHo397HP6DgUFPYohMFCEX8BKZqNJQOLtEzU Z6EK4RmMy5ObeAhDy1jQ+7kwJdtoitDvJSXcTFlIs3D7mO/lzVNPufzAny1zoIG/RB fYlFLo8RBRSy/KtXlWwLx/Z8vpFtuYmRknzhZIaw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Starke Subject: [PATCH 4.9 39/66] tty: n_gsm: fix missing explicit ldisc flush Date: Tue, 10 May 2022 15:07:29 +0200 Message-Id: <20220510130730.915130452@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220510130729.762341544@linuxfoundation.org> References: <20220510130729.762341544@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Daniel Starke commit 17eac652028501df7ea296b1d9b9c134db262b7d upstream. In gsm_cleanup_mux() the muxer is closed down and all queues are removed. However, removing the queues is done without explicit control of the underlying buffers. Flush those before freeing up our queues to ensure that all outgoing queues are cleared consistently. Otherwise, a new mux connection establishment attempt may time out while the underlying tty is still busy sending out the remaining data from the previous connection. Fixes: e1eaea46bb40 ("tty: n_gsm line discipline") Cc: stable@vger.kernel.org Signed-off-by: Daniel Starke Link: https://lore.kernel.org/r/20220414094225.4527-10-daniel.starke@siemens.com Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -2101,6 +2101,7 @@ static void gsm_cleanup_mux(struct gsm_m gsm_dlci_release(gsm->dlci[i]); mutex_unlock(&gsm->mutex); /* Now wipe the queues */ + tty_ldisc_flush(gsm->tty); list_for_each_entry_safe(txq, ntxq, &gsm->tx_list, list) kfree(txq); INIT_LIST_HEAD(&gsm->tx_list);