FAILED: patch "[PATCH] USB: serial: io_edgeport: handle unbound ports on URB" failed to apply to 4.9-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.9-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 e37d1aeda737a20b1846a91a3da3f8b0f00cf690 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Fri, 17 Jan 2020 10:50:23 +0100
Subject: [PATCH] USB: serial: io_edgeport: handle unbound ports on URB
 completion

Check for NULL port data in the shared interrupt and bulk completion
callbacks to avoid dereferencing a NULL pointer in case a device sends
data for a port device which isn't bound to a driver (e.g. due to a
malicious device having unexpected endpoints or after an allocation
failure on port probe).

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/io_edgeport.c b/drivers/usb/serial/io_edgeport.c
index 9690a5f4b9d6..0582d78bdb1d 100644
--- a/drivers/usb/serial/io_edgeport.c
+++ b/drivers/usb/serial/io_edgeport.c
@@ -716,7 +716,7 @@ static void edge_interrupt_callback(struct urb *urb)
 			if (txCredits) {
 				port = edge_serial->serial->port[portNumber];
 				edge_port = usb_get_serial_port_data(port);
-				if (edge_port->open) {
+				if (edge_port && edge_port->open) {
 					spin_lock_irqsave(&edge_port->ep_lock,
 							  flags);
 					edge_port->txCredits += txCredits;
@@ -1825,7 +1825,7 @@ static void process_rcvd_data(struct edgeport_serial *edge_serial,
 				port = edge_serial->serial->port[
 							edge_serial->rxPort];
 				edge_port = usb_get_serial_port_data(port);
-				if (edge_port->open) {
+				if (edge_port && edge_port->open) {
 					dev_dbg(dev, "%s - Sending %d bytes to TTY for port %d\n",
 						__func__, rxLen,
 						edge_serial->rxPort);