CVE-2024-42113

What it actually does

Uninitialized wx->num_q_vectors variable in the txgbe/wx driver causes invalid memory access and kernel panic inside wx_alloc_q_vectors when MSI or INTx interrupt mode is active.

Why it matters to the business

Systems using affected Linux kernel versions with txgbe network hardware may experience sudden crashes and service outages when the driver initializes under MSI/INTx interrupts, leading to unplanned downtime.

How an attack unfolds

An attacker with local access or the ability to influence driver loading triggers MSI/INTx interrupt configuration; the uninitialized num_q_vectors value is then dereferenced during queue vector allocation, resulting in a kernel panic that can be used for denial of service.

How to fix it

Upgrade the Linux kernel to a version containing commit 9edc7a83cd40ac96ff14fe3a17a38f7ace6611df or later; rebuild and reboot with the patched kernel. Where immediate patching is not possible, force MSI-X interrupt mode if hardware supports it.

How to confirm the fix worked

Confirm the running kernel contains commit 9edc7a83cd40ac96ff14fe3a17a38f7ace6611df; verify num_q_vectors is explicitly initialized before wx_alloc_q_vectors is called; test driver load under MSI/INTx mode without panic.

Typical attack path

1. Load or reload the txgbe driver on a system configured for MSI/INTx interrupts
2. Driver initialization path reaches wx_alloc_q_vectors with uninitialized num_q_vectors
3. Kernel dereferences invalid pointer and panics

How to detect it

Review kernel logs for oops/panic messages referencing wx_alloc_q_vectors or num_q_vectors during driver initialization; correlate with txgbe module load events.

What your security team should do

• Prioritize kernel upgrade on all systems exposing txgbe hardware
• Monitor vendor advisories for backported fixes in distribution kernels
• Test interrupt mode configuration in lab environments before production rollout