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@kernel.org 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@vger.kernel.org # 3.12 Signed-off-by: Johan Hovold johan@kernel.org Link: https://lore.kernel.org/r/20191009153848.8664-5-johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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;