CVE-2022-48768

What it actually does

Missing kfree on error path after kstrdup allocation in histogram parameter handling leads to memory leak in Linux kernel tracing.

Why it matters to the business

Repeated triggering of error conditions in kernel tracing can gradually exhaust system memory, leading to instability or crashes in environments relying on histogram tracing.

How an attack unfolds

An attacker triggers the specific error path during histogram parameter parsing to leak memory repeatedly; no known public exploits or relevant threat actor activity for this issue.

How to fix it

Update Linux kernel to version 5.4.176 or later, or apply commit 8a8878ebb596281f50fc0b9a6e1f23f0d7f154e8 in the stable tree.

How to confirm the fix worked

Verify kernel version is at least 5.4.176 or confirm the kfree(p) call is present after kstrdup in tracing/histogram code.

Typical attack path

1. Identify system using kernel tracing with histograms
2. Craft input to trigger kstrdup error path in param handling
3. Repeat to accumulate leaks and exhaust memory

How to detect it

Use kernel memory leak detection tools to scan for unreleased allocations from kstrdup in tracing code; review system logs for repeated histogram param errors.

What your security team should do

• Prioritize kernel upgrades on systems using tracing histograms
• Enable kernel memory leak detectors like kmemleak for monitoring
• Review tracing configurations to minimize exposure to the affected code path