CVE-2023-52747

What it actually does

The vulnerability causes a resource leak in the InfiniBand hfi1 driver when a copyout operation fails, preventing proper cleanup of allocated resources.

Why it matters to the business

Repeated triggering could lead to gradual depletion of kernel resources, potentially causing system instability or crashes in affected Linux environments over time.

How an attack unfolds

An attacker with local access to trigger specific InfiniBand operations that cause a copyout failure in the hfi1 driver can exploit the missing resource restoration, leading to leaks that accumulate into denial of service.

How to fix it

Update the Linux kernel to include commit 00d9e212b8a39e6ffcf31b9d2e503d2bf6009d45 or later versions containing the fix.

How to confirm the fix worked

Verify the presence of the fix commit in the kernel source tree or confirm deployment of updated kernel packages from the distribution.

Typical attack path

1. Identify systems using hfi1 InfiniBand hardware
2. Craft input to trigger error path in copyout operation
3. Repeat the sequence to accumulate resource leaks

How to detect it

Review kernel logs for repeated hfi1 driver error paths involving copyout failures; monitor system-wide resource counters for unexplained growth without corresponding workload increases.

What your security team should do

• Apply the kernel update containing the fix commit at the earliest opportunity
• Monitor kernel logs and resource usage for anomalies on systems with InfiniBand hardware
• Restrict unprivileged access to InfiniBand interfaces where feasible