In the Linux kernel, the following vulnerability has been resolved: ACPI: platform: Use...

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

ACPI: platform: Use acpi_bus_get_primary_device()

The acpi_get_first_physical_node() usage in acpi_platform_fill_resource() and acpi_create_platform_device() is generally unsafe because in theory the device returned by it may be freed at any time [1].

It is also inefficient because acpi_get_first_physical_node() is called multiple times for the same argument which can be avoided.

Address these issues by using acpi_bus_get_primary_device() instead of acpi_get_first_physical_node() and adjusting the code to call it just once at the beginning of and acpi_create_platform_device() and drop the device reference acquired by it upon the return from that function.