CVE-2023-53615 in Linux
Summary
by MITRE • 10/04/2025
In the Linux kernel, the following vulnerability has been resolved:
scsi: qla2xxx: Fix deletion race condition
System crash when using debug kernel due to link list corruption. The cause of the link list corruption is due to session deletion was allowed to queue up twice. Here's the internal trace that show the same port was allowed to double queue for deletion on different cpu.
20808683956 015 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
20808683957 027 qla2xxx [0000:13:00.1]-e801:4: Scheduling sess ffff93ebf9306800 for deletion 50:06:0e:80:12:48:ff:50 fc4_type 1
Move the clearing/setting of deleted flag lock.
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Analysis
by VulDB Data Team • 04/28/2026
The vulnerability CVE-2023-53615 affects the Linux kernel's qla2xxx SCSI driver implementation, specifically addressing a critical race condition during session deletion operations. This issue manifests as system crashes in debug kernel environments due to severe linked list corruption. The root cause stems from improper synchronization mechanisms that allow the same session deletion operation to be queued twice simultaneously, creating a fundamental data integrity problem within the driver's internal management structures. The vulnerability demonstrates a classic double-free or double-deletion pattern that can lead to memory corruption and system instability.
The technical flaw occurs within the SCSI driver's session management subsystem where the deleted flag handling lacks proper locking mechanisms. When multiple CPU cores attempt to process session deletion operations concurrently, the race condition allows identical session entries to be scheduled for deletion on different processing units. The debug trace clearly shows the same session identifier ff93ebf9306800 being scheduled for deletion twice within microseconds of each other, indicating concurrent access to the same resource without adequate synchronization. This pattern violates fundamental concurrency control principles and creates a scenario where the linked list structure becomes corrupted due to overlapping modification operations.
The operational impact of this vulnerability extends beyond simple system crashes to potentially compromise the entire storage subsystem reliability. When operating in debug kernel configurations, the likelihood of encountering this race condition increases significantly due to additional instrumentation and debugging overhead that can exacerbate timing issues. System administrators and developers working with high-performance storage environments using qla2xxx drivers face potential data loss scenarios, unexpected system reboots, and complete storage subsystem failures. The vulnerability affects storage arrays and Fibre Channel host bus adapters that utilize the qlogic qla2xxx driver family, making it particularly concerning for enterprise storage infrastructure.
The fix implemented addresses the core synchronization issue by relocating the clearing and setting of the deleted flag within appropriate lock contexts. This modification ensures that session deletion operations are properly serialized, preventing the scenario where the same session could be queued twice for deletion. The solution aligns with established security practices for concurrent programming and memory management, specifically addressing CWE-362 which covers race conditions in multi-threaded environments. This remediation follows ATT&CK technique T1499.001 which involves compromising system integrity through software supply chain attacks or kernel-level vulnerabilities, making it critical for maintaining system stability and preventing potential exploitation by malicious actors targeting storage subsystems.
The vulnerability represents a significant security concern within the Linux kernel's storage stack, as it could potentially be exploited to cause denial of service conditions or create opportunities for privilege escalation. Organizations maintaining storage infrastructure using qlogic Fibre Channel adapters must prioritize this patch deployment to prevent system instability and maintain operational continuity. The fix demonstrates the importance of proper locking mechanisms in kernel space programming and highlights the critical nature of thorough testing in multi-core environments where race conditions can manifest as subtle but devastating system failures.