CVE-2022-49098

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 HVFEATUREGUESTCRASHMSR_AVAILABLE capability is set.

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

References

Affected packages

Debian:11 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.10.113-1

Affected versions

5.*

5.10.46-4

5.10.46-5

5.10.70-1~bpo10+1

5.10.70-1

5.10.84-1

5.10.92-1~bpo10+1

5.10.92-1

5.10.92-2

5.10.103-1~bpo10+1

5.10.103-1

5.10.106-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:12 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.17.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name: linux
Purl: pkg:deb/debian/linux?arch=source

Affected ranges

Type: ECOSYSTEM
Events: Introduced

0Unknown introduced version / All previous versions are affected

Fixed

5.17.3-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}