CVE-2022-50320

/// Technical description

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

ACPI: tables: FPDT: Don't call acpi_os_map_memory() on invalid phys address

On a Packard Bell Dot SC (Intel Atom N2600 model) there is a FPDT table

which contains invalid physical addresses, with high bits set which fall

outside the range of the CPU-s supported physical address range.

Calling acpi_os_map_memory() on such an invalid phys address leads to

the below WARN_ON in ioremap triggering resulting in an oops/stacktrace.

Add code to verify the physical address before calling acpi_os_map_memory()

to fix / avoid the oops.

[ 1.226900] ioremap: invalid physical address 3001000000000000

[ 1.226949] ------------[ cut here ]------------

[ 1.226962] WARNING: CPU: 1 PID: 1 at arch/x86/mm/ioremap.c:200 __ioremap_caller.cold+0x43/0x5f

[ 1.226996] Modules linked in:

[ 1.227016] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc3+ #490

[ 1.227029] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/

/// 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