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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 913ECC76186 for ; Mon, 29 Jul 2019 19:40:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 650F9217D9 for ; Mon, 29 Jul 2019 19:40:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429257; bh=9SmH12nidC7+mKOl+ADbmfoN5bZixqCjWUVB9ZLnOiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=x1ugwoimlV1hMrGGq1IjDxOmlV8DMV+18ua+6O0/4n1tYMCBF258Ci3aOnZPZp3cR EiB+xSXz/S5/8C7Ew/UfRvY5ZmZwJopd+fOz8tGeBaUAcCB5qlwiWiCldZmlo5B/wC AjltYxgQt8D5g8kB7aSdBdchp2ovvOM/2l2xaUpo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389233AbfG2Tk4 (ORCPT ); Mon, 29 Jul 2019 15:40:56 -0400 Received: from mail.kernel.org ([198.145.29.99]:56232 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729212AbfG2Tkx (ORCPT ); Mon, 29 Jul 2019 15:40:53 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 08DC020C01; Mon, 29 Jul 2019 19:40:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564429252; bh=9SmH12nidC7+mKOl+ADbmfoN5bZixqCjWUVB9ZLnOiQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hr0+l6J81cRhY6YvVVljVeGdG/phN33Oe7XBooh6obqIp6m2/HgWLeXcEkCewzbjX JyyuREMJSrFrYiieQeqCSYzdaHaTylFoiHRgBJfPa6sk1rTC4CtOwa8OQ138fyHqwr teebumllgewfo4eZ1I+bhN8BitJ0xtu5Xds91MFQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sergey Organov , Sasha Levin Subject: [PATCH 4.19 032/113] serial: imx: fix locking in set_termios() Date: Mon, 29 Jul 2019 21:21:59 +0200 Message-Id: <20190729190703.575473801@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190729190655.455345569@linuxfoundation.org> References: <20190729190655.455345569@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 4e828c3e09201512be5ee162393f334321f7cf01 ] imx_uart_set_termios() called imx_uart_rts_active(), or imx_uart_rts_inactive() before taking port->port.lock. As a consequence, sport->port.mctrl that these functions modify could have been changed without holding port->port.lock. Moved locking of port->port.lock above the calls to fix the issue. Signed-off-by: Sergey Organov Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/imx.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index 0f67197a3783..105de92b0b3b 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -382,6 +382,7 @@ static void imx_uart_ucrs_restore(struct imx_port *sport, } #endif +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_active(struct imx_port *sport, u32 *ucr2) { *ucr2 &= ~(UCR2_CTSC | UCR2_CTS); @@ -390,6 +391,7 @@ static void imx_uart_rts_active(struct imx_port *sport, u32 *ucr2) mctrl_gpio_set(sport->gpios, sport->port.mctrl); } +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2) { *ucr2 &= ~UCR2_CTSC; @@ -399,6 +401,7 @@ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2) mctrl_gpio_set(sport->gpios, sport->port.mctrl); } +/* called with port.lock taken and irqs caller dependent */ static void imx_uart_rts_auto(struct imx_port *sport, u32 *ucr2) { *ucr2 |= UCR2_CTSC; @@ -1554,6 +1557,16 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, old_csize = CS8; } + del_timer_sync(&sport->timer); + + /* + * Ask the core to calculate the divisor for us. + */ + baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16); + quot = uart_get_divisor(port, baud); + + spin_lock_irqsave(&sport->port.lock, flags); + if ((termios->c_cflag & CSIZE) == CS8) ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS; else @@ -1597,16 +1610,6 @@ imx_uart_set_termios(struct uart_port *port, struct ktermios *termios, ucr2 |= UCR2_PROE; } - del_timer_sync(&sport->timer); - - /* - * Ask the core to calculate the divisor for us. - */ - baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16); - quot = uart_get_divisor(port, baud); - - spin_lock_irqsave(&sport->port.lock, flags); - sport->port.read_status_mask = 0; if (termios->c_iflag & INPCK) sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR); -- 2.20.1