Linux Kernel Qla2xxx Driver Preemption Issue Vulnerability

A vulnerability has been identified in the Linux kernel's QLogic Fibre Channel driver (qla2xxx) related to improper use of the 'smp_processor_id()' function in preemptible code. This issue triggers a kernel warning about the preemption state, which can lead to potential instability or unexpected behavior in the system. The vulnerability was observed in the 'qla_create_qpair()' function during the initialization of QLogic devices, as reported in kernel version 5.14.0-29.el9.x86_64.

Impact

The vulnerability can cause kernel warnings and may lead to instability in the system by improperly handling processor preemption.

Reproduction

The vulnerability can be reproduced by loading the QLogic Fibre Channel driver (qla2xxx) on a system running the affected Linux kernel version. During the driver's initialization process, the 'qla_create_qpair()' function will be called, which improperly uses 'smp_processor_id()' in a preemptible context. This will trigger a kernel warning about the preemption state, indicating that the driver is not adhering to proper concurrency practices.