In the Linux kernel, the following vulnerability has been resolved: ACPI: x86: Add adev NULL check to acpi_quirk_skip_serdev_enumeration() acpi_dev_hid_match() does not check for adev == NULL, dereferencing it unconditional. Add a check for adev being NULL before calling acpi_dev_hid_match(). At the moment acpi_quirk_skip_serdev_enumeration() is never called with a controller_parent without an ACPI companion, but better safe than sorry.