patch "USB: adutux: fix use-after-free on release" added to usb-linus

patch "USB: adutux: fix use-after-free on release" added to usb-linus

[gregkh]

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

    USB: adutux: fix use-after-free on release

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


From 123a0f125fa3d2104043697baa62899d9e549272 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Wed, 9 Oct 2019 17:38:44 +0200
Subject: USB: adutux: fix use-after-free on release

The driver was accessing its struct usb_device in its release()
callback without holding a reference. This would lead to a
use-after-free whenever the device was disconnected while the character
device was still open.

Fixes: 66d4bc30d128 ("USB: adutux: remove custom debug macro")
Cc: stable <stable@vger.kernel.org>     # 3.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191009153848.8664-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/misc/adutux.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/misc/adutux.c b/drivers/usb/misc/adutux.c
index f9efec719359..6f5edb9fc61e 100644
--- a/drivers/usb/misc/adutux.c
+++ b/drivers/usb/misc/adutux.c
@@ -149,6 +149,7 @@ static void adu_delete(struct adu_device *dev)
 	kfree(dev->read_buffer_secondary);
 	kfree(dev->interrupt_in_buffer);
 	kfree(dev->interrupt_out_buffer);
+	usb_put_dev(dev->udev);
 	kfree(dev);
 }
 
@@ -664,7 +665,7 @@ static int adu_probe(struct usb_interface *interface,
 
 	mutex_init(&dev->mtx);
 	spin_lock_init(&dev->buflock);
-	dev->udev = udev;
+	dev->udev = usb_get_dev(udev);
 	init_waitqueue_head(&dev->read_wait);
 	init_waitqueue_head(&dev->write_wait);
 
-- 
2.23.0