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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 325F9C2F3BE for ; Mon, 21 Jan 2019 14:07:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 04E222085A for ; Mon, 21 Jan 2019 14:07:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079663; bh=XmAfEcltjVxSY9D5kU8caeP4+M0px1n5q7CYEd6BweM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=poJFVAcqyvItRO2S/f3ZCWXDvpnZEGMmb0tOlpj2hf7PttVQiscq7uoLW4phGBL/I CXTLXvDaqvxcghi4UGGbW1I70ThUQiU0DsqaJq+quXncCzk15UEquSVo+2AcXZjXmN B6JbKlTpNDRIG8oF5nc3vhhjhZTKMRTLVsmBBNW8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732177AbfAUN7Z (ORCPT ); Mon, 21 Jan 2019 08:59:25 -0500 Received: from mail.kernel.org ([198.145.29.99]:45410 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732172AbfAUN7Y (ORCPT ); Mon, 21 Jan 2019 08:59:24 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 88B3820879; Mon, 21 Jan 2019 13:59:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548079164; bh=XmAfEcltjVxSY9D5kU8caeP4+M0px1n5q7CYEd6BweM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nOJNaLUZFJ9pC396+ZeQTFed2U55hK7jRDz49PmeozE9fOqX83qHtEXnkbdEVMNV0 wBYTQ3H5HlPjKV52l+E3KmH0iAETCwfiKHj7gA4/VSk+MinTwqGqKPAp/yLb4uoDgI tvGn0TftRCuX1hZdJ59ZsUtrctuTu1bYOAHlROVg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jiri Slaby , Jiri Slaby , Mark Rutland , Dmitry Safonov Subject: [PATCH 4.19 03/99] tty: Simplify tty->count math in tty_reopen() Date: Mon, 21 Jan 2019 14:47:55 +0100 Message-Id: <20190121134914.048479004@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190121134913.924726465@linuxfoundation.org> References: <20190121134913.924726465@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dmitry Safonov commit cf62a1a13749db0d32b5cdd800ea91a4087319de upstream. As notted by Jiri, tty_ldisc_reinit() shouldn't rely on tty counter. Simplify math by increasing the counter after reinit success. Cc: Jiri Slaby Link: lkml.kernel.org/r/<20180829022353.23568-2-dima@arista.com> Suggested-by: Jiri Slaby Reviewed-by: Jiri Slaby Tested-by: Mark Rutland Signed-off-by: Dmitry Safonov Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_io.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1271,16 +1271,13 @@ static int tty_reopen(struct tty_struct if (retval) return retval; - tty->count++; - if (tty->ldisc) - goto out_unlock; + if (!tty->ldisc) + retval = tty_ldisc_reinit(tty, tty->termios.c_line); + tty_ldisc_unlock(tty); - retval = tty_ldisc_reinit(tty, tty->termios.c_line); - if (retval) - tty->count--; + if (retval == 0) + tty->count++; -out_unlock: - tty_ldisc_unlock(tty); return retval; }