USB: serial: mos7720: fix control-message error handling

Make sure to log an error on short transfers when reading a device
register.

Also clear the provided buffer (which if often an uninitialised
automatic variable) on errors as the driver currently does not bother to
check for errors.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
This commit is contained in:
Johan Hovold 2017-01-12 14:56:17 +01:00
parent 36356a669e
commit 0d130367ab
1 changed files with 7 additions and 2 deletions

View File

@ -234,11 +234,16 @@ static int read_mos_reg(struct usb_serial *serial, unsigned int serial_portnum,
status = usb_control_msg(usbdev, pipe, request, requesttype, value,
index, buf, 1, MOS_WDR_TIMEOUT);
if (status == 1)
if (status == 1) {
*data = *buf;
else if (status < 0)
} else {
dev_err(&usbdev->dev,
"mos7720: usb_control_msg() failed: %d\n", status);
if (status >= 0)
status = -EIO;
*data = 0;
}
kfree(buf);
return status;