CVE-2024-34030

What it actually does

Missing allocation failure check in of_pci_prop_intr_map allows kcalloc to return NULL which is later dereferenced, causing a kernel NULL pointer dereference during PCI interrupt-map property creation.

Why it matters to the business

Kernel panic or system instability on affected Linux systems under memory pressure, leading to denial of service and potential loss of availability for servers, embedded devices, and Android-based products.

How an attack unfolds

An attacker with the ability to trigger PCI device enumeration or device-tree parsing under constrained memory conditions can force the allocation failure path, resulting in a subsequent NULL dereference that crashes the kernel.

How to fix it

Apply the upstream fix in commit b5f31d1470c4fdfae368feeb389768ba8d24fb34 or later; update to a stable kernel branch containing this commit. Reboot after patching.

How to confirm the fix worked

Confirm the presence of commit b5f31d1470c4fdfae368feeb389768ba8d24fb34 in the running kernel source or verify that of_pci_prop_intr_map now returns -ENOMEM on allocation failure via code review or kernel build inspection.

Typical attack path

1. Trigger PCI device discovery or device-tree parsing on the target system
2. Exhaust kernel memory to cause kcalloc failure inside of_pci_prop_intr_map
3. Allow execution to continue with a NULL pointer instead of returning -ENOMEM
4. Trigger dereference of the NULL interrupt-map pointer, inducing kernel panic

How to detect it

Search kernel logs for NULL pointer dereference oops messages originating from PCI or device-tree interrupt-map code paths around the time of device enumeration; no reliable post-exploitation artifacts exist for this class of vulnerability.

What your security team should do

• Prioritize patching production Linux kernels within the next maintenance window
• Monitor EPSS and threat intel for any rise in exploit maturity
• Test the updated kernel in staging environments before broad deployment
• Review device-tree and PCI enumeration workloads for memory-pressure exposure