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:
- A PCI device with a non-VGA class is the boot display
- That device is probed first and it is not a VGA device so
- Non-primary GPU has a VGA class and it ends up calling sysfb_disable()
- NULL pointer dereference via sysfb_disable() since the resources
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 into the mutex Drop primary variable in aperture_remove_conflicting_pci_devices() Drop __init on pci sysfb_pci_dev_is_enabled()