[PATCH 4.19 010/103] USB: serial: opticon: fix control-message timeouts

Greg Kroah-Hartman
2020-01-22T09:40:25Z

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: stable <stable@vger.kernel.org> # 2.6.39
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
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
@@ -113,7 +113,7 @@ 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)