firmware: arm_scmi: Quiesce notifications before teardown

Summary

In the Linux kernel, the following vulnerability has been resolved: firmware: arm_scmi: Quiesce notifications before teardown scmi_notification_exit() clears and releases the notification instance, but transport callbacks can still deliver incoming notifications until the TX/RX channels are freed. During remove, an RX interrupt in that window can enter scmi_notify() while notification state is being torn down and then dereference freed memory. The same ordering exists on the probe error path after notification initialization. The notification late-init worker has a separate lifetime issue: protocol event registration queues ni->init_work on the system workqueue, so destroying ni->notify_wq does not drain that work. If the devres group is released while init_work is still pending or running, the late-init worker can dereference the freed notification instance. Quiesce the notification core before TX/RX channels are torn down, then clean up the channels before releasing the notification core resources. Use disable_work_sync() so future late-init queueing is rejected and any already queued or running late-init work has completed before channel teardown starts.

Timeline

1. Sep 17, 2026, 4:11 PM UTCCVE published
2. Oct 19, 2026, 9:05 AM UTCRecord last updated

Affected versions

• Linux Linux

  From 1e7cbfaa66d39e78bd24df0c78b55df68176b59e · fixed in 6778bcabd2e0c32f73476f0bc6369013692540be; From 1e7cbfaa66d39e78bd24df0c78b55df68176b59e · fixed in 2aac23bc0a79af41104d99823bb250fae92ba144; From 1e7cbfaa66d39e78bd24df0c78b55df68176b59e · fixed in 5e30d3d16d1a9e599be4dcea872874e65e2c277b; From 1e7cbfaa66d39e78bd24df0c78b55df68176b59e · fixed in 8e49055d0d495c9c07575ad8e111d9eaf0efb13f

• Linux Linux

  5.15

• KernelLinux

  From 5.15.0 · fixed in 6.12.110; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6

References 4