CVE-2023-52678

What it actually does

Failure to verify that a kernel list is non-empty before calling list_first_entry in AMD KFD topology code can lead to invalid pointer usage or potential memory corruption.

Why it matters to the business

Systems using AMD GPUs with KFD enabled may experience kernel panics or driver instability during topology initialization, impacting GPU-accelerated workloads.

How an attack unfolds

An attacker with local access could attempt to trigger the affected topology functions by manipulating GPU device states or loading specific configurations that result in empty lists, potentially leading to crashes or undefined behavior.

How to fix it

Update the Linux kernel to include commit 4525525cb7161d08f95d0e47025323dd10214313 which adds the necessary list emptiness check.

How to confirm the fix worked

Verify the presence of the fix by checking the kernel source for the emptiness check before list_first_entry in kfd_topology.c or confirm the commit is applied.

Typical attack path

1. Gain local access to the system
2. Interact with AMD KFD driver to trigger kfd_create_indirect_link_prop or kfd_add_peer_prop
3. Cause empty list condition to dereference invalid pointers

How to detect it

Search system logs for warnings from kfd_topology.c functions mentioning possible NULL pointers for gpu_link or iolinks.

• kfd_create_indirect_link_prop
• kfd_add_peer_prop
• can 'gpu_link' even be NULL?

What your security team should do

• Apply the kernel patch immediately on AMD GPU systems
• Monitor for related kernel warnings in logs
• Test GPU functionality post-update