From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793211053; b=3l9/a+//CGiw+kp29DiiAnVQg/k8fBOQU8PJC627awy0hdMMVVP+ZAb7hYCzLddVRwrq 8/HMugG95gfKSKxzdf+mHVZSQRWJZXGgYgH+8EjjSipK0xJb52FKiKs63Xtdzx96JRQnN NP1wMQRAT2G8xXMMjgD+x4ZiPQFw/Le2ghH2RUypqGfhf+cY3D8GfAEbzmvgCO9bM+9Mr 5Gy8AoA55YqSy8SYr/F8j6lJJ6b5/oR5ikcWP5Q/kTWaJmvulmeAvvHUowcy9TfFYVLJ6 Fa8JclBpJXpX4XolMi9CkUH5mrL6uPt+TiAxj612x9ujXFBgPgRCXL1+7lKi08ysInw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793211053; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=6yFIVMPsuesJ2YZ0NdXrkcUcOAfnxUpOW9nvNnZjek8=; b=VnZWuFR0xMLK5keuW9Eu2KimX5M7DZtymeL5BGhevJuBtZTX/ZdZffbPgn7ISnCb2r+L qwI/dwLKRh8xe0qUTJtv858c8TTa6zoH2uuDQqEnEmDL4f0NwVsaG8IwcW+F974O07jw2 D3Ap+IQP2KCP6Dpi44KJrRC98kMn37uN9sQQPIIyRwVqMn9TD6SXEZzvwZSq97ZCIFVJv SksXEwgyyyxSKNE2uO3D4osBApuYS5akmXNzPa31MxlKm9aPO0lZ2/W5fRACNsSNwVmmp XCM5sy9I0X78iYC/xv13NwGDIORHu7pjr1CM0tNzz6S6yOKcHmxZlyP9KXF68g//YKA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=jHZuUe6m; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B7538606A951; Wed, 28 Oct 2026 18:10:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=jHZuUe6m Received: by smtp.kernel.org (Postfix) with ESMTPSA id 048031F01829; Wed, 28 Oct 2026 18:10:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793211052; bh=6yFIVMPsuesJ2YZ0NdXrkcUcOAfnxUpOW9nvNnZjek8=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=jHZuUe6mXTYJDl1jSoeVyn7VTFwNs2kDp6Q5+0jFrWP8UoLz+TVSkfrvOqWe3zZUH 7z6XmgtSvlviS9JlJpymVKV8Ar9t1mJ/eyh5nbSQK3p0yMMHD6gE3tjt622gDgK08R wo6MngNl3/FtTTwG3TUwtdHDs4BIqTRfESYySSOg= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bill Pemberton , Johan Hovold Subject: [PATCH 5.15 242/571] USB: serial: quatech2: fix baud rate overflow Date: Wed, 28 Oct 2026 17:56:29 +0100 Message-ID: <20261028170013.747696893@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170008.009143722@linuxfoundation.org> References: <20261028170008.009143722@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit ec06546b43b612cefc851558981b4955c0ef9e46 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/quatech2.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -54,6 +54,7 @@ #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 @@ -158,7 +159,7 @@ static inline int calc_baud_divisor(int 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)); @@ -267,9 +268,9 @@ static void qt2_set_termios(struct tty_s 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); @@ -301,6 +302,18 @@ static void qt2_set_termios(struct tty_s 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) @@ -397,7 +410,7 @@ static int qt2_open(struct tty_struct *t port_priv->device_port = (u8) device_port; if (tty) - qt2_set_termios(tty, port, &tty->termios); + qt2_set_termios(tty, port, NULL); return 0;