Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Content-Type: text/plain; charset="UTF-8"
Content-Disposition: inline
Content-Transfer-Encoding: 8bit
MIME-Version: 1.0
From:   Ben Hutchings <ben@decadent.org.uk>
To:     linux-kernel@vger.kernel.org, stable@vger.kernel.org
CC:     akpm@linux-foundation.org, Denis Kirjanov <kda@linux-powerpc.org>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        "Martin Jansen" <martin.jansen@opticon.com>,
        "Johan Hovold" <johan@kernel.org>
Date:   Fri, 24 Apr 2020 00:06:50 +0100
Message-ID: <lsq.1587683028.532135298@decadent.org.uk>
Subject: [PATCH 3.16 183/245] USB: serial: opticon: fix control-message
 timeouts
In-Reply-To: <lsq.1587683027.831233700@decadent.org.uk>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

3.16.83-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@kernel.org>

commit 5e28055f340275a8616eee88ef19186631b4d136 upstream.

The driver was issuing synchronous uninterruptible control requests
without using a timeout. This could lead to the driver hanging
on open() or tiocmset() due to a malfunctioning (or malicious) device
until the device is physically disconnected.

The USB upper limit of five seconds per request should be more than
enough.

Fixes: 309a057932ab ("USB: opticon: add rts and cts support")
Cc: Martin Jansen <martin.jansen@opticon.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
 drivers/usb/serial/opticon.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/usb/serial/opticon.c
+++ b/drivers/usb/serial/opticon.c
@@ -116,7 +116,7 @@ static int send_control_msg(struct usb_s
 	retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
 				requesttype,
 				USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
-				0, 0, buffer, 1, 0);
+				0, 0, buffer, 1, USB_CTRL_SET_TIMEOUT);
 	kfree(buffer);
 
 	if (retval < 0)