[PATCH 4.14 030/119] USB: legousbtower: fix memleak on disconnect

From: Greg Kroah-Hartman
Date: Sun Oct 27 2019 - 17:08:10 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit b6c03e5f7b463efcafd1ce141bd5a8fc4e583ae2 upstream.

If disconnect() races with release() after a process has been
interrupted, release() could end up returning early and the driver would
fail to free its driver data.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20191010125835.27031-3-johan@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/misc/legousbtower.c | 5 +----
1 file changed, 1 insertion(+), 4 deletions(-)

--- a/drivers/usb/misc/legousbtower.c
+++ b/drivers/usb/misc/legousbtower.c
@@ -423,10 +423,7 @@ static int tower_release (struct inode *
goto exit;
}

- if (mutex_lock_interruptible(&dev->lock)) {
- retval = -ERESTARTSYS;
- goto exit;
- }
+ mutex_lock(&dev->lock);

if (dev->open_count != 1) {
dev_dbg(&dev->udev->dev, "%s: device not opened exactly once\n",