CVE-2023-54167 m68k: mm: Move initrd phys_to_virt handling after paging_init()
A kernel crash occurs when booting with an initial ramdisk on specific m68k platforms due to premature memory address translation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-54167?
CVE-2023-54167 is a vulnerability in Linux, published on 30 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
m68k: mm: Move initrd phys_to_virt handling after paging_init()
When booting with an initial ramdisk on platforms where physical memory does not start at address zero (e.g. on Amiga):
initrd: 0ef0602c - 0f800000 Zone ranges: DMA [mem 0x0000000008000000-0x000000f7ffffffff] Normal empty Movable zone start for each node Early memory node ranges node 0: [mem 0x0000000008000000-0x000000000f7fffff] Initmem setup node 0 [mem 0x0000000008000000-0x000000000f7fffff] Unable to handle kernel access at virtual address (ptrval) Oops: 00000000 Modules linked in: PC: [<00201d3c>] memcmp+0x28/0x56
As phys_to_virt() relies on m68k_memoffset and module_fixup(), it must not be called before paging_init(). Hence postpone the phys_to_virt handling for the initial ramdisk until after calling paging_init().
While at it, reduce #ifdef clutter by using IS_ENABLED() instead.
Which versions are affected by CVE-2023-54167?
How do I fix CVE-2023-54167?
Apply the vendor's patch.
Is CVE-2023-54167 being exploited?
There is no known exploitation of CVE-2023-54167 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54167, DEBIAN-CVE-2023-54167, GHSA-m7mj-mw9m-293g, UBUNTU-CVE-2023-54167.