From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 483D73B8D7E; Tue, 15 Sep 2026 12:40:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789476036; cv=none; b=Mrfr9iWlgXKgofvgEuSPjfuRCxQ3JpcI2mIUhTqCkMT4eCEFqx5L8sSwvIZEYh3eVtvpOhXAX3RT2PcJN2gscO2cZsozcOVi+kTVy3c2NmFMVsjbDSHQtMeeGrMoUOalZW3W3nKAT4PWz56hokbA5xD00tEaxaU4pbT3F6SPFvw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789476036; c=relaxed/simple; bh=snT6Yz9RSt19k2+lENWpwl0vksvJTAQQkBH3UvjeBWE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NJ7SfNKWN7n/iVa7zFyP0qDwPVogiDPExu6lc+CEjIFy1BSsekczpglh2/vi7uhJcJjOZgnG1Piv3Ki3D3s2ogAA/cg9CSvXVUDOWmk5qUFA6OhTyMeFuZQDQp/3y5Ea401GhUBE9PZqPFKLyOh/U/dwpSJsbkU8KkKpL8r5KcE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KE5xeMCb; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KE5xeMCb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2F0D51F00898; Tue, 15 Sep 2026 12:40:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789476035; bh=5kziq8mwhiUUnzUkkV2DS+y2m3ZeYHn6bUEVx6OwQWQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KE5xeMCbR/Vk0h6jiSGr9UWEWm5APziOdEjfyicr9wAlRPmQfNAGELW3Uk4y4sHzX r89RA8GcNJhgdOAtU8xJTiYj05nHch6r6gLj38LczFrS+S6A1n71T0kQc9nmiu0oUB s9PDmikKMtTfwg6WfPRScNQm5hNTNYsELI+Oo1htuMuMIEqeSAIL90bjcQZ652yxpg g5jE34XccdtaLoQ0s3eIT+PKKCJMr03jVCAye4w5jQsE+5dFhtbxj+795vY9nXHogJ np8msI3Zz8SGPokp4wSCEIbh4cFAGtxkQfTdTQ/PqoJnuiB7JN8ylb0lrsEtzFHP1E 3k/0SjHLC6psg== Received: from johan by xi.lan with local (Exim 4.99.4) (envelope-from ) id 1x6SSc-00000005fOs-1Y24; Tue, 15 Sep 2026 14:40:30 +0200 From: Johan Hovold To: Johan Hovold Cc: Greg Kroah-Hartman , Bill Pemberton , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH 2/2] USB: serial: quatech2: fix baud rate overflow Date: Tue, 15 Sep 2026 14:40:12 +0200 Message-ID: <20260915124012.1350748-3-johan@kernel.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260915124012.1350748-1-johan@kernel.org> References: <20260915124012.1350748-1-johan@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The requested baud rate is incorrectly truncated to 16 bits so that line speeds above 65535 bps cannot be set. Use 32 bits for the rate while rejecting rates outside of [50,921600] to avoid having the 16-bit divisor overflow. Fixes: f7a33e608d9a ("USB: serial: add quatech2 usb to serial driver") Cc: stable@vger.kernel.org # 3.5 Cc: Bill Pemberton Signed-off-by: Johan Hovold --- drivers/usb/serial/quatech2.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c index dc2b39810a26..3b4df3ac7c73 100644 --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -52,6 +52,7 @@ #define QT2_XMIT_FLUSH 0x05 /* no following info */ #define QT2_CONTROL_ESCAPE 0xff /* pass through previous 2 control bytes */ +#define MIN_BAUD_RATE 50 #define MAX_BAUD_RATE 921600 #define DEFAULT_BAUD_RATE 9600 @@ -156,7 +157,7 @@ static inline int calc_baud_divisor(int baudrate) static inline int qt2_set_port_config(struct usb_device *dev, unsigned char port_number, - u16 baudrate, u16 lcr) + speed_t baudrate, u16 lcr) { int divisor = calc_baud_divisor(baudrate); u16 index = ((u16) (lcr << 8) | (u16) (port_number)); @@ -257,9 +258,9 @@ static void qt2_set_termios(struct tty_struct *tty, struct usb_device *dev = port->serial->dev; struct qt2_port_private *port_priv; struct ktermios *termios = &tty->termios; - u16 baud; unsigned int cflag = termios->c_cflag; u16 new_lcr = 0; + speed_t baud; int status; port_priv = usb_get_serial_port_data(port); @@ -277,6 +278,18 @@ static void qt2_set_termios(struct tty_struct *tty, if (!baud) baud = 9600; + if (baud < MIN_BAUD_RATE || baud > MAX_BAUD_RATE) { + if (old_termios) + baud = tty_termios_baud_rate(old_termios); + else + baud = clamp(baud, MIN_BAUD_RATE, MAX_BAUD_RATE); + + tty_encode_baud_rate(tty, baud, baud); + + if (!baud) + baud = 9600; + } + status = qt2_set_port_config(dev, port_priv->device_port, baud, new_lcr); if (status < 0) @@ -373,7 +386,7 @@ static int qt2_open(struct tty_struct *tty, struct usb_serial_port *port) port_priv->device_port = (u8) device_port; if (tty) - qt2_set_termios(tty, port, &tty->termios); + qt2_set_termios(tty, port, NULL); return 0; -- 2.55.0