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

drm/hyperv: Fix address space leak when Hyper-V DRM device is removed

When a Hyper-V DRM device is probed, the driver allocates MMIO space for
the vram, and maps it cacheable. If the device removed, or in the error
path for device probing, the MMIO space is released but no unmap is done.
Consequently the kernel address space for the mapping is leaked.

Fix this by adding iounmap() calls in the device removal path, and in the
error path during device probing.

https://git.kernel.org/stable/c/158242b56bf465a73e1edeac0fe828a8acad4499

https://git.kernel.org/stable/c/24f1bbfb2be77dad82489c1468bbb14312aab129

https://git.kernel.org/stable/c/ad27b4a51495490b815580d9b935e8eee14d1a9c

https://git.kernel.org/stable/c/aed709355fd05ef747e1af24a1d5d78cd7feb81e

https://git.kernel.org/stable/c/c40cd24bfb9bfbb315c118ca14ebe6cf52e2dd1e