This is a note to let you know that I've just added the patch titled
USB: legousbtower: 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 726b55d0e22ca72c69c947af87785c830289ddbc Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@xxxxxxxxxx>
Date: Wed, 9 Oct 2019 17:38:47 +0200
Subject: USB: legousbtower: 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: fef526cae700 ("USB: legousbtower: remove custom debug macro")
Cc: stable <stable@xxxxxxxxxxxxxxx> # 3.12
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20191009153848.8664-5-johan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/misc/legousbtower.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/usb/misc/legousbtower.c b/drivers/usb/misc/legousbtower.c
index 44d6a3381804..9d4c52a7ebe0 100644
--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -296,6 +296,7 @@ static inline void tower_delete (struct lego_usb_tower *dev)
kfree (dev->read_buffer);
kfree (dev->interrupt_in_buffer);
kfree (dev->interrupt_out_buffer);
+ usb_put_dev(dev->udev);
kfree (dev);
}
@@ -810,7 +811,7 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
mutex_init(&dev->lock);
- dev->udev = udev;
+ dev->udev = usb_get_dev(udev);
dev->open_count = 0;
dev->disconnected = 0;
--
2.23.0
