Bug 2536749 (CVE-2026-93081) - CVE-2026-93081 kernel: firmware: arm_scmi: Fix SCMI device destroy lifetimes
Summary: CVE-2026-93081 kernel: firmware: arm_scmi: Fix SCMI device destroy lifetimes
Keywords:
Status: NEW
Alias: CVE-2026-93081
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-09-17 19:24 UTC by OSIDB Bzimport
Modified: 2026-10-20 11:33 UTC (History)
17 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)

Description OSIDB Bzimport 2026-09-17 19:24:55 UTC
In the Linux kernel, the following vulnerability has been resolved:

firmware: arm_scmi: Fix SCMI device destroy lifetimes

scmi_child_dev_find() drops the reference returned by
device_find_child() before returning the scmi_device pointer. A
concurrent unregister can then release the device while the destroy path
is still using the returned pointer.

Make the lookup helper return the device_find_child() reference and keep
it until scmi_device_destroy() has finished unregistering the child.

Also split device_unregister() in __scmi_device_destroy() so the SCMI bus
ID is not made reusable until after device_del() has removed the old
scmi_dev.N name from sysfs. This avoids a new SCMI device reusing the
same ID while the old device is still registered.

The final device release callback is also a possible cleanup path when
SCMI children are deleted by driver core recursion rather than
__scmi_device_destroy(). Release the SCMI bus ID from a common helper
used by destroy, register-failure and final-release paths, and clear
scmi_dev->id after freeing it so the final release cannot free the same
ID again.


Note You need to log in before you can comment on or make changes to this bug.