CVE-2024-35930 in Linux
Summary
by MITRE • 05/19/2024
In the Linux kernel, the following vulnerability has been resolved:
scsi: lpfc: Fix possible memory leak in lpfc_rcv_padisc()
The call to lpfc_sli4_resume_rpi() in lpfc_rcv_padisc() may return an unsuccessful status. In such cases, the elsiocb is not issued, the completion is not called, and thus the elsiocb resource is leaked.
Check return value after calling lpfc_sli4_resume_rpi() and conditionally release the elsiocb resource.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 12/30/2024
The vulnerability identified as CVE-2024-35930 represents a memory leak condition within the Linux kernel's SCSI subsystem, specifically affecting the LightPulse Fibre Channel Host Bus Adapter (lpfc) driver. This flaw exists in the lpfc_rcv_padisc() function which handles received PADI (PLOGI Accept) discovery requests in Fibre Channel networks. The issue arises from improper error handling in the driver's resource management logic, creating a potential denial of service scenario that could degrade system performance over time.
The technical flaw manifests when the lpfc_sli4_resume_rpi() function is invoked within the lpfc_rcv_padisc() context. This function is responsible for resuming RPI (Remote Port Identifier) operations in the SLI (Serial Link Interface) 4 protocol implementation. When lpfc_sli4_resume_rpi() returns an unsuccessful status, indicating a failure in the RPI resumption process, the calling function fails to properly handle this error condition. The elsiocb (extended link iocb) resource, which represents a critical I/O control block structure, is not released back to the system's memory pool, resulting in a memory leak that persists until the system is rebooted.
This memory leak vulnerability directly impacts system stability and resource utilization within Linux environments that employ LightPulse Fibre Channel adapters. The operational consequences extend beyond simple resource waste, as repeated occurrences of this condition can lead to progressive memory exhaustion, potentially causing system slowdowns, application failures, or complete system hang conditions. The vulnerability affects systems running kernel versions where the lpfc driver processes Fibre Channel discovery protocols, particularly those utilizing SLI 4 architecture with LightPulse HBA hardware configurations.
The fix implemented addresses this issue by introducing proper error checking after the lpfc_sli4_resume_rpi() call. The solution requires checking the return value of this function and conditionally releasing the elsiocb resource when the function fails. This approach aligns with standard security practices for resource management in kernel space code, ensuring that all allocated resources are properly accounted for and released regardless of function success or failure states. The mitigation strategy follows established patterns for preventing resource leaks in kernel drivers and corresponds to CWE-401, which specifically addresses memory leaks in software systems.
From an attack perspective, this vulnerability represents a low-severity denial of service risk rather than a direct exploitation vector. However, in environments where Fibre Channel storage networks are heavily utilized, the cumulative effect of memory leaks could create significant operational impact. The vulnerability is particularly concerning in enterprise storage environments where continuous system availability is critical. System administrators should prioritize applying the kernel patch that resolves this issue, especially in production environments where multiple discovery operations might occur over time. The fix demonstrates proper defensive programming practices that should be adopted across similar kernel subsystems to prevent analogous memory leak scenarios.
This vulnerability relates to ATT&CK technique T1499.004, which covers resource exhaustion via denial of service, and specifically targets the kernel's memory management subsystem. The flaw exemplifies how seemingly minor error handling oversights in kernel drivers can create persistent resource consumption issues that degrade system performance over time. The resolution approach emphasizes the importance of defensive programming in kernel space where resource management is critical for system stability and security posture.