The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 3018dd3fa114b13261e9599ddb5656ef97a1fa17 Mon Sep 17 00:00:00 2001

From: Johan Hovold johan@kernel.org Date: Fri, 17 Jan 2020 10:50:25 +0100 Subject: [PATCH] USB: serial: keyspan: handle unbound ports

Check for NULL port data in the control URB completion handlers to avoid dereferencing a NULL pointer in the unlikely case where a port device isn't bound to a driver (e.g. after an allocation failure on port probe()).

Fixes: 0ca1268e109a ("USB Serial Keyspan: add support for USA-49WG & USA-28XG") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable stable@vger.kernel.org Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Johan Hovold johan@kernel.org

diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c index e66a59ef43a1..aa3dbce22cfb 100644 --- a/drivers/usb/serial/keyspan.c +++ b/drivers/usb/serial/keyspan.c @@ -1058,6 +1058,8 @@ static void usa49_glocont_callback(struct urb *urb) for (i = 0; i < serial->num_ports; ++i) { port = serial->port[i]; p_priv = usb_get_serial_port_data(port); + if (!p_priv) + continue;

if (p_priv->resend_cont) { dev_dbg(&port->dev, "%s - sending setup\n", __func__); @@ -1459,6 +1461,8 @@ static void usa67_glocont_callback(struct urb *urb) for (i = 0; i < serial->num_ports; ++i) { port = serial->port[i]; p_priv = usb_get_serial_port_data(port); + if (!p_priv) + continue;

if (p_priv->resend_cont) { dev_dbg(&port->dev, "%s - sending setup\n", __func__);