Patch "USB: serial: mxuport: fix use-after-free in probe error path" has been added to the 4.4-stable tree

Patch "USB: serial: mxuport: fix use-after-free in probe error path" 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: mxuport: fix use-after-free in probe error path

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-mxuport-fix-use-after-free-in-probe-error-path.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 9e45284984096314994777f27e1446dfbfd2f0d7 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Sun, 8 May 2016 20:08:01 +0200
Subject: USB: serial: mxuport: fix use-after-free in probe error path

From: Johan Hovold <johan@kernel.org>

commit 9e45284984096314994777f27e1446dfbfd2f0d7 upstream.

The interface read and event URBs are submitted in attach, but were
never explicitly unlinked by the driver. Instead the URBs would have
been killed by usb-serial core on disconnect.

In case of a late probe error (e.g. due to failed minor allocation),
disconnect is never called and we could end up with active URBs for an
unbound interface. This in turn could lead to deallocated memory being
dereferenced in the completion callbacks.

Fixes: ee467a1f2066 ("USB: serial: add Moxa UPORT 12XX/14XX/16XX
driver")
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/serial/mxuport.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/drivers/usb/serial/mxuport.c
+++ b/drivers/usb/serial/mxuport.c
@@ -1259,6 +1259,15 @@ static int mxuport_attach(struct usb_ser
 	return 0;
 }
 
+static void mxuport_release(struct usb_serial *serial)
+{
+	struct usb_serial_port *port0 = serial->port[0];
+	struct usb_serial_port *port1 = serial->port[1];
+
+	usb_serial_generic_close(port1);
+	usb_serial_generic_close(port0);
+}
+
 static int mxuport_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
 	struct mxuport_port *mxport = usb_get_serial_port_data(port);
@@ -1361,6 +1370,7 @@ static struct usb_serial_driver mxuport_
 	.probe			= mxuport_probe,
 	.port_probe		= mxuport_port_probe,
 	.attach			= mxuport_attach,
+	.release		= mxuport_release,
 	.calc_num_ports		= mxuport_calc_num_ports,
 	.open			= mxuport_open,
 	.close			= mxuport_close,


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

queue-4.4/usb-serial-quatech2-fix-use-after-free-in-probe-error-path.patch
queue-4.4/usb-serial-option-add-support-for-cinterion-ph8-and-ahxx.patch
queue-4.4/usb-serial-io_edgeport-fix-memory-leaks-in-attach-error-path.patch
queue-4.4/usb-serial-mxuport-fix-use-after-free-in-probe-error-path.patch
queue-4.4/usb-serial-option-add-even-more-zte-device-ids.patch
queue-4.4/usb-serial-keyspan-fix-use-after-free-in-probe-error-path.patch
queue-4.4/usb-serial-option-add-more-zte-device-ids.patch
queue-4.4/usb-serial-io_edgeport-fix-memory-leaks-in-probe-error-path.patch