CVE-2026-93092: firmware: arm_scmi: Unregister device notifier before IDR teardown
In the Linux kernel, the following vulnerability has been resolved:
firmware: armscmi: Unregister device notifier before IDR teardown
The requested-devices notifier looks up protocol fwnodes from the activeprotocols IDR. During remove, unregister the notifier before releasing and destroying activeprotocols so no notifier callback can race with the IDR teardown.
Keep the bus notifier registered until after the protocol state is torn down, matching the existing remove ordering for SCMI bus users.
Event History
Frequently Asked Questions
Which systems and events are relevant to this issue?
The issue is in the Linux kernel ARM SCMI firmware subsystem. It can occur during device removal when the requested-devices notifier runs while the active_protocols IDR is being released and destroyed.
What is the required fix ordering?
The requested-devices notifier must be unregistered before active_protocols is released and destroyed, preventing its callback from looking up protocol fwnodes during IDR teardown. The SCMI bus notifier should remain registered until protocol state teardown is complete.