Patch "USB: serial: fix potential NULL-dereference at probe" has been added to the 4.4-stable tree

Patch "USB: serial: fix potential NULL-dereference at probe" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    USB: serial: fix potential NULL-dereference at probe

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-serial-fix-potential-null-dereference-at-probe.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 126d26f66d9890a69158812a6caa248c05359daa Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Fri, 21 Oct 2016 12:56:27 +0200
Subject: USB: serial: fix potential NULL-dereference at probe

From: Johan Hovold <johan@kernel.org>

commit 126d26f66d9890a69158812a6caa248c05359daa upstream.

Make sure we have at least one port before attempting to register a
console.

Currently, at least one driver binds to a "dummy" interface and requests
zero ports for it. Should such an interface also lack endpoints, we get
a NULL-deref during probe.

Fixes: e5b1e2062e05 ("USB: serial: make minor allocation dynamic")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/serial/usb-serial.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/usb/serial/usb-serial.c
+++ b/drivers/usb/serial/usb-serial.c
@@ -1077,7 +1077,8 @@ static int usb_serial_probe(struct usb_i
 
 	serial->disconnected = 0;
 
-	usb_serial_console_init(serial->port[0]->minor);
+	if (num_ports > 0)
+		usb_serial_console_init(serial->port[0]->minor);
 exit:
 	module_put(type->driver.owner);
 	return 0;


Patches currently in stable-queue which might be from johan@kernel.org are

queue-4.4/usb-serial-ftdi_sio-add-support-for-infineon-triboard-tc2x7.patch
queue-4.4/usb-serial-fix-potential-null-dereference-at-probe.patch