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

Drivers: hv: vmbus: Fix potential crash on module unload

The vmbus driver relies on the panic notifier infrastructure to perform
some operations when a panic event is detected. Since vmbus can be built
as module, it is required that the driver handles both registering and
unregistering such panic notifier callback.

After commit 74347a99e73a ("x86/Hyper-V: Unload vmbus channel in hv panic callback")
though, the panic notifier registration is done unconditionally in the module
initialization routine whereas the unregistering procedure is conditionally
guarded and executes only if HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE capability
is set.

This patch fixes that by unconditionally unregistering the panic notifier
in the module's exit routine as well.

https://git.kernel.org/stable/c/2133c422a103cf7c7768c37b9ac382e73b691892

https://git.kernel.org/stable/c/3d0078f8bddd58d9bb1ad40bbe929f8633abb276

https://git.kernel.org/stable/c/5ea98d0f5f035c1bcf1517ccec0e024ae35a48b2

https://git.kernel.org/stable/c/6b4c0149a56147b29169e07000d566162892722a

https://git.kernel.org/stable/c/792f232d57ff28bbd5f9c4abe0466b23d5879dc8

https://git.kernel.org/stable/c/cf580d2e3884dbafd6b90269b03a24d661578624

https://git.kernel.org/stable/c/dcd6b1a624c0ffa21034d8b1e02e9d068458f596