In the Linux kernel, the following vulnerability has been resolved:

vduse: hold vduse_lock across IDR lookup in open path

vduse_dev_open() looks up struct vduse_dev through the IDR and then
acquires dev->lock only after vduse_lock has been dropped.

This leaves a window where a concurrent VDUSE_DESTROY_DEV can remove the
same object from the IDR and free it before the open path locks the
device, leading to a use-after-free.

Close this race by keeping vduse_lock held until dev->lock has been
acquired in the open path, matching the lock ordering already used by
the destroy path.