CVE-2026-53164 iommu/dma: Do not try to iommu_map a 0 length region in swiotlb
A kernel bug causes a warning and potential crash when mapping zero-length regions in SWIOTLB, triggered by specific NVMe drives.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-53164?
CVE-2026-53164 is a medium-severity vulnerability in Linux kernel, published on 25 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
iommu/dma: Do not try to iommu_map a 0 length region in swiotlb
iommu_dma_iova_link_swiotlb() 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 iommu_map() 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 WARN_ON.
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.
Which versions are affected by CVE-2026-53164?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53164?
Apply the vendor's patch.
Is CVE-2026-53164 being exploited?
There is no known exploitation of CVE-2026-53164 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-53164, DEBIAN-CVE-2026-53164, GHSA-rwq9-95v8-58fq, UBUNTU-CVE-2026-53164.