Executive brief
A vulnerability was identified in the Linux kernel's Qualcomm SLIMBus driver, which manages communication between the main processor and peripheral components like audio hardware. Under specific conditions during system startup, the driver may attempt to process hardware signals before it has finished setting itself up. This race condition can lead to a system crash or failure to boot, potentially impacting the availability of devices using this hardware.
Technical details
A race condition exists in the Qualcomm SLIMBus NGD driver (drivers/slimbus/qcom-ngd-ctrl.c) within the Linux kernel. The vulnerability occurs because interrupt enablement and the registration of Subsystem Restart (SSR) and Protection Domain Registry (PDR) callbacks happen before the NGD device is fully initialized. If a remoteproc starts in parallel with the driver probe, or if a hardware interrupt occurs prematurely, the callbacks operate on uninitialized data, specifically scheduling work on a NULL 'ngd_up_work' structure. This results in a kernel warning/fault and boot failure. The fix involves reordering the initialization sequence to ensure the NGD device is registered before enabling interrupts and callbacks.
Affected products
- Linux Linux 4.19 to 6.12.94, 6.18.36
Timeline
- 2026-05-30: patched: Initial patch authored by Bjorn Andersson
- 2026-07-01: advisory: CVE published in NVD dataset