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=-8.5 required=3.0 tests=DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 20234C48BD6 for ; Wed, 26 Jun 2019 14:14:48 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D82EB2147A for ; Wed, 26 Jun 2019 14:14:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="i6o48SLt"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="PSS223db" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D82EB2147A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=do4VjB5pGYjSsOk+Y8Q+prXU9sTSmVK+NkzPutPpnRs=; b=i6o48SLtQszXkAadzXjocPmnEI 610qY0KSZFcQaZEjOQ7c8s7bMYPvdy095C7SVhH3IdqfQldudVHLsWZPKH2EJKUV2uKKF2V04ZBPw Wr8qgsa/wOuNxThF8PxK1OqhVQNkeLKm7MkTFYP/OwWAGZovDGFD9uiK91N3zurdWK37z4YSKLy9w ZzO8AMt47Ato1Uy3bMJhBsr1XYlT4QtkEwHBzvGTzHqfeY9bSwv6Trn+adOQ61JWiGlheqPrb6Q5I ryzFTyreC0M3euFJ/KEvXyLUkB6PPo5oltnTu5LyQh5iYVUS1epC9jN+2Ydnt9TNCJI38w9wlhgAT kNk1alKQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hg8h5-0004CL-Q1; Wed, 26 Jun 2019 14:14:39 +0000 Received: from mail-lj1-x242.google.com ([2a00:1450:4864:20::242]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hg8gl-0003xx-Jm for linux-arm-kernel@lists.infradead.org; Wed, 26 Jun 2019 14:14:20 +0000 Received: by mail-lj1-x242.google.com with SMTP id m23so2356351lje.12 for ; Wed, 26 Jun 2019 07:14:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=bZEuBr/u7QmcmUUX/8Ym5nImEHkVz1m2bXUhPQcNDuE=; b=PSS223db/d4jR+7QIlHArthBCcpQqnYC18l7YmJGLgfztQImucQ9dT1X9xs0qtTis2 gYnkmfT5qfyFRpplR2r+qA0NX5D3VfPlGczY1z1dyzCrMrGQF/rClvOTdgW72zWSUs4L Kpn2C4UfaJxv91FtrCm7Tioe0NYV4xzlllwqtJTY1qgvPfwSxZ2DtY1o9G1KJfa0dFO/ 2R3o79DIoEe2KhqfXlq44zZCe6YiMLYeJCWp3hyGx8LCFsyhwDBj/YOrCKltKhcIR+n5 AeBGt9Iy4xR8Wqgh70rpydWSZ+V4iP2y/LTSIR6uzbdT/ulcZ6Iw0GqrwyLi9NDWuLH+ kPhA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=bZEuBr/u7QmcmUUX/8Ym5nImEHkVz1m2bXUhPQcNDuE=; b=cS+TVFPMEO/A6IWFnKyPCRDBXldO0du5Lgr9EydUHrP6xsrL4eDy/089Xz3Sc6am1e kfJKpPHpZovBffYBJoLiHzNo2yHt/r1qf9wWUL/zs3OEe2b4dMdGpseVZUHtvJE76wB6 YUAsTypf1QyX7U2k7i6A+fcL2cLmlnwOs+6PUwcagNiGP1v+H9hE5w7bU8wikzLLVKDl L7t4yzzU3pGRR9VUGn4mlMvaiIVpR4sb637lvs86YQAcgeCbXXtvajytT5N2mToeqoEp Yi/UbWhEEKf1ZFWdOtGACOGPBmK1dRxlGhsBxGoBsYAR2Bj1XgNVxyyGYiPFGNgDNtzV 6org== X-Gm-Message-State: APjAAAXUQMXK9CPraYfA8ZKcQLr1W4nbFHYYHC7MWqVi707C21M5vfXa TRKkflCldOqxN9KmX8d6OEO9edi+ X-Google-Smtp-Source: APXvYqzoEA2Ur4kBMLRQMwb8qjOtucgHIrwKndnQ/vYw7CBLOdEYrcXt8Ekye1Bai8jgGYBgMf8BVg== X-Received: by 2002:a2e:9250:: with SMTP id v16mr3048462ljg.89.1561558455912; Wed, 26 Jun 2019 07:14:15 -0700 (PDT) Received: from osv.localdomain ([89.175.180.246]) by smtp.gmail.com with ESMTPSA id 25sm2863825ljn.62.2019.06.26.07.14.15 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 26 Jun 2019 07:14:15 -0700 (PDT) From: Sergey Organov To: Sascha Hauer Subject: [PATCH v2 1/7] serial: imx: fix locking in set_termios() Date: Wed, 26 Jun 2019 17:11:27 +0300 Message-Id: <1561558293-7683-2-git-send-email-sorganov@gmail.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1561558293-7683-1-git-send-email-sorganov@gmail.com> References: <20190614072801.3187-1-s.hauer@pengutronix.de> <1561558293-7683-1-git-send-email-sorganov@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190626_071419_655882_CF6C46EA X-CRM114-Status: GOOD ( 13.48 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Pengutronix Kernel Team , NXP Linux Team , linux-arm-kernel@lists.infradead.org, linux-serial@vger.kernel.org, =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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. Reviewed-by: Sascha Hauer Tested-by: Sascha Hauer Signed-off-by: Sergey Organov --- 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 dff75dc..1055124 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -383,6 +383,7 @@ 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); @@ -391,6 +392,7 @@ 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; @@ -400,6 +402,7 @@ 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; @@ -1550,6 +1553,16 @@ 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 @@ -1593,16 +1606,6 @@ 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); -- 2.10.0.1.g57b01a3 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel