CVE-2024-56714: Vulnerability in Linux Linux

Severity: mediumType: vulnerabilityCVE-2024-56714

In the Linux kernel, the following vulnerability has been resolved: ionic: no double destroy workqueue There are some FW error handling paths that can cause us to try to destroy the workqueue more than once, so let's be sure we're checking for that. The case where this popped up was in an AER event where the handlers got called in such a way that ionic_reset_prepare() and thus ionic_dev_teardown() got called twice in a row. The second time through the workqueue was already destroyed, and destroy_workqueue() choked on the bad wq pointer. We didn't hit this in AER handler testing before because at that time we weren't using a private workqueue. Later we replaced the use of the system workqueue with our own private workqueue but hadn't rerun the AER handler testing since then.

AI Analysis

Technical Summary

CVE-2024-56714 is a vulnerability identified in the Linux kernel related to the handling of workqueues within the ionic network driver. Specifically, the issue arises from improper management of workqueue destruction during firmware (FW) error handling paths. The vulnerability occurs when the system attempts to destroy a workqueue more than once, leading to a double destroy scenario. This happens in the context of Advanced Error Reporting (AER) events where the handlers invoke ionic_reset_prepare() and ionic_dev_teardown() consecutively. The second invocation attempts to destroy a workqueue that has already been destroyed, causing the destroy_workqueue() function to operate on an invalid pointer, which can lead to kernel instability or crashes. The root cause was the replacement of the system workqueue with a private workqueue without revalidating the AER handler testing, allowing this double destruction path to remain undetected until now. Although no known exploits are currently reported in the wild, this vulnerability represents a kernel-level flaw that could be triggered under specific error conditions related to the ionic driver’s error recovery mechanisms.

Potential Impact

For European organizations, the impact of CVE-2024-56714 could be significant, particularly for those relying on Linux-based infrastructure that utilizes the ionic network driver, commonly found in certain network interface cards (NICs) used in data centers and enterprise environments. Exploitation of this vulnerability could lead to kernel crashes or denial of service (DoS) conditions, disrupting critical services and potentially causing downtime. While this vulnerability does not directly lead to privilege escalation or data leakage, the resulting instability could impact availability and reliability of systems, affecting business continuity. Organizations with high-availability requirements or those operating critical network infrastructure may face operational risks. Additionally, if attackers develop exploit techniques, this could be leveraged as part of a broader attack chain to degrade system performance or cause targeted disruptions.

Mitigation Recommendations

To mitigate CVE-2024-56714, European organizations should prioritize updating their Linux kernel to the latest patched versions where this issue has been resolved. Since the vulnerability is tied to the ionic driver’s workqueue management, ensuring that all network drivers and kernel modules are up to date is critical. Organizations should also audit their use of the ionic driver in their environments and consider temporarily disabling or replacing affected NICs if patching is delayed. Monitoring kernel logs for repeated AER events or unusual workqueue destruction errors can help detect attempts to trigger this vulnerability. For environments with strict uptime requirements, implementing redundant network paths and failover mechanisms can reduce the impact of potential DoS conditions. Finally, organizations should maintain robust incident response plans to quickly address any kernel crashes or instability that may arise.