CVE-2026-93199: i3c: master: Do not treat master device as a duplicate target
In the Linux kernel, the following vulnerability has been resolved:
i3c: master: Do not treat master device as a duplicate target
i3cmastersearchi3cdevduplicate() searches the bus for another I3C device with the same PID as the reference device. The search can match master->this, causing the controller itself to be returned as a duplicate.
Since the controller is not a target device, it cannot be a duplicate of one. Exclude master->this from matching so that the function only returns real duplicate target devices.
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Configuration
Apply the resolved change: update the i3c master search logic so i3c_master_search_i3c_dev_duplicate() does not treat the master device (master->this) as a duplicate target; it should only return real duplicate target devices.
Linux kernel i3c i3c master search duplicate handling = Do not treat master device as a duplicate target
Event History
Frequently Asked Questions
Which systems are exposed to this issue?
Systems using the Linux kernel I3C master subsystem are relevant. The issue occurs when duplicate-device searching can compare an I3C device against the controller's own master device.
What is required to trigger the incorrect duplicate match?
The duplicate search must encounter the master controller device, master->this, with the same PID as the reference device. Before the fix, the search could return that controller even though it is not an I3C target device.
How can I determine whether the issue has been addressed?
Verify that the kernel's i3c_master_search_i3c_dev_duplicate() implementation explicitly excludes master->this from duplicate matching. The supplied stable kernel references identify commits containing the resolution.