CVE-2025-21876

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 6.14.0-rc3

Description A vulnerability in the Linux kernel has been resolved, related to suspicious RCU usage in the iommu/vt-d component. The issue was caused by a commit that moved the call to enable drhd fault handling() to a code path that does not hold any lock while traversing the drhd list. This fix ensures that the dmar global lock lock is held when traversing the drhd list. Without this fix, a warning is triggered, indicating suspicious RCU usage. The estimated number of potentially affected devices worldwide is not available.

Recommendations For Linux kernel versions prior to 6.14.0-rc3, update to a version that includes the fix for the suspicious RCU usage issue. As a temporary workaround, consider restricting access to the iommu/vt-d component to minimize the risk of exploitation. Avoid using the enable drhd fault handling() function until the issue is resolved.