Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756742AbaBUALx (ORCPT ); Thu, 20 Feb 2014 19:11:53 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:46094 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755996AbaBTXx2 (ORCPT ); Thu, 20 Feb 2014 18:53:28 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Peter Hurley Subject: [PATCH 3.13 36/99] n_tty: Fix stale echo output Date: Thu, 20 Feb 2014 15:52:31 -0800 Message-Id: <20140220235119.271296228@linuxfoundation.org> X-Mailer: git-send-email 1.9.0 In-Reply-To: <20140220235118.191692546@linuxfoundation.org> References: <20140220235118.191692546@linuxfoundation.org> User-Agent: quilt/0.61-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13-stable review patch. If anyone has any objections, please let me know. ------------------ From: Peter Hurley commit e2613be5093d04e6589924d36a1e363eef3c87c7 upstream. When echoes cannot be flushed to output (usually because the tty has no more write room) and L_ECHO is subsequently turned off, then when L_ECHO is turned back on, stale echoes are output. Output completed echoes regardless of the L_ECHO setting: 1. before normal writes to that tty 2. if the tty was stopped by soft flow control and is being restarted Reported-by: Mikulas Patocka Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_tty.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -813,8 +813,7 @@ static void process_echoes(struct tty_st struct n_tty_data *ldata = tty->disc_data; size_t echoed; - if ((!L_ECHO(tty) && !L_ECHONL(tty)) || - ldata->echo_mark == ldata->echo_tail) + if (ldata->echo_mark == ldata->echo_tail) return; mutex_lock(&ldata->output_lock); @@ -1238,7 +1237,8 @@ n_tty_receive_signal_char(struct tty_str if (L_ECHO(tty)) { echo_char(c, tty); commit_echoes(tty); - } + } else + process_echoes(tty); isig(signal, tty); return; } @@ -1269,7 +1269,7 @@ n_tty_receive_char_special(struct tty_st if (I_IXON(tty)) { if (c == START_CHAR(tty)) { start_tty(tty); - commit_echoes(tty); + process_echoes(tty); return 0; } if (c == STOP_CHAR(tty)) { @@ -1821,8 +1821,10 @@ static void n_tty_set_termios(struct tty * Fix tty hang when I_IXON(tty) is cleared, but the tty * been stopped by STOP_CHAR(tty) before it. */ - if (!I_IXON(tty) && old && (old->c_iflag & IXON) && !tty->flow_stopped) + if (!I_IXON(tty) && old && (old->c_iflag & IXON) && !tty->flow_stopped) { start_tty(tty); + process_echoes(tty); + } /* The termios change make the tty ready for I/O */ wake_up_interruptible(&tty->write_wait); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/