CVE-2026-53164: iommu/dma: Do not try to iommu_map a 0 length region in swiotlb
In the Linux kernel, the following vulnerability has been resolved:
iommu/dma: Do not try to iommumap a 0 length region in swiotlb
iommudmaiovalinkswiotlb() processes a mapping that is unaligned in three parts, the head, middle and trailer. If the middle is empty because there are no aligned pages it will call down to iommumap() with a 0 size which the iommupt implementation will fail as illegal.
It then tries to do an error unwind and starts from the wrong spot corrupting the mapping so the eventual destruction triggers a WARNON.
Check for 0 length and avoid mapping and use offset not 0 as the starting point to unlink.
This is frequently triggered by using some kinds of thunderbolt NVMe drives that trigger forced SWIOTLB for unaligned memory. NVMe seems to pass in oddly aligned buffers for the passthrough commands from smartctl that hit this condition.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-53164?
CVE-2026-53164 has a risk rating of 33, indicating a moderate severity level.
How do I fix CVE-2026-53164?
To resolve CVE-2026-53164, update the Linux kernel to the latest version that includes the fix.
What systems are affected by CVE-2026-53164?
CVE-2026-53164 affects systems running the vulnerable versions of the Linux kernel that handle IO memory mappings.
What are the potential impacts of CVE-2026-53164?
The potential impacts of CVE-2026-53164 include system instability and improper handling of memory mappings.
Is there a workaround for CVE-2026-53164?
Currently, the recommended solution for CVE-2026-53164 is to apply the official kernel update, as there are no known workarounds.