CVE-2024-46698

/// Technical description

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

video/aperture: optionally match the device in sysfb_disable()

In aperture_remove_conflicting_pci_devices(), we currently only

call sysfb_disable() on vga class devices. This leads to the

following problem when the pimary device is not VGA compatible:

1. A PCI device with a non-VGA class is the boot display

2. That device is probed first and it is not a VGA device so

sysfb_disable() is not called, but the device resources

are freed by aperture_detach_platform_device()

3. Non-primary GPU has a VGA class and it ends up calling sysfb_disable()

4. NULL pointer dereference via sysfb_disable() since the resources

have already been freed by aperture_detach_platform_device() when

it was called by the other device.

Fix this by passing a device pointer to sysfb_disable() and checking

the device to determine if we should execute it or not.

v2: Fix build when CONFIG_SCREEN_INFO is not set

v3: Move device check in

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References