CVE-2026-64152

A flaw was found in the Linux kernel's Input/Output Memory Management Unit (IOMMU) subsystem when iommu_debug is enabled. This issue occurs because an error handling path attempts to unmap memory without a proper initial mapping, leading to an inconsistent state within the IOMMU's debugging and tracing mechanisms. This malfunction could result in unbalanced tracking, potentially affecting system stability or the accuracy of IOMMU debugging information.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

To mitigate this issue in Red Hat In-Vehicle OS, ensure that the iommu_debug kernel parameter is not enabled. This can typically be achieved by verifying that iommu_debug is not present in the kernel command line arguments during boot. Disabling this debug feature may impact diagnostic capabilities but will prevent the vulnerable code path from being exercised. A system reboot is required for changes to kernel boot parameters to take effect.