From: Johan Hovold johan@kernel.org
commit 4d5ef53f75c22d28f490bcc5c771fcc610a9afa4 upstream.
Check for NULL port data in reset_resume() to avoid dereferencing a NULL pointer in case the port device isn't bound to a driver (e.g. after a failed control request at port probe).
Fixes: 1ded7ea47b88 ("USB: ch341 serial: fix port number changed after resume") Cc: stable stable@vger.kernel.org # 2.6.30 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/ch341.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)
--- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -592,9 +592,13 @@ static int ch341_tiocmget(struct tty_str static int ch341_reset_resume(struct usb_serial *serial) { struct usb_serial_port *port = serial->port[0]; - struct ch341_private *priv = usb_get_serial_port_data(port); + struct ch341_private *priv; int ret;
+ priv = usb_get_serial_port_data(port); + if (!priv) + return 0; + /* reconfigure ch341 serial port after bus-reset */ ch341_configure(serial->dev, priv);