From patchwork Wed May 4 16:45:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 569839 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 1FA27C433FE for ; Wed, 4 May 2022 16:59:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354423AbiEDRCg (ORCPT ); Wed, 4 May 2022 13:02:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38312 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1355668AbiEDRAT (ORCPT ); Wed, 4 May 2022 13:00:19 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0CE74BBB2; Wed, 4 May 2022 09:52:00 -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 ams.source.kernel.org (Postfix) with ESMTPS id 4CB91B82752; Wed, 4 May 2022 16:52:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EF6B0C385AF; Wed, 4 May 2022 16:51:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1651683119; bh=cs89dHarpUa70cX95WQueutECdjMdtC6/UGYiMszhTI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M0x359ZqbPUPDYJFIr6jZgBoRpCIwKjfiFSb6bCj5WKFSd+rcrYT5+fxrdAXMhOi5 YqNaiLqZ3ndgfJG9mpq7f25J/T64ks/zs+gXDNcErp8ohE5DWcMTa5OcJlARyXRfQH uQS/JrOd0qqJO7q/JLaXO8zhs24xR5fLpiesQ218= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Starke Subject: [PATCH 5.10 123/129] tty: n_gsm: fix missing explicit ldisc flush Date: Wed, 4 May 2022 18:45:15 +0200 Message-Id: <20220504153031.220885329@linuxfoundation.org> X-Mailer: git-send-email 2.36.0 In-Reply-To: <20220504153021.299025455@linuxfoundation.org> References: <20220504153021.299025455@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@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 @@ -2079,6 +2079,7 @@ 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);