CVE-2026-53164

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux433a76207dcf5facc0183acb790f6e8398585258 < ab61c990a87d084f5565ee70340543e3a5394697affected
LinuxLinux433a76207dcf5facc0183acb790f6e8398585258 < b16f8d40bac9ced838d24c9842707af9ecae92e2affected
LinuxLinux433a76207dcf5facc0183acb790f6e8398585258 < 6ec91df8aff77e2e8fe3179c1f3fc15b43a40ba3affected
LinuxLinux6.16affected
LinuxLinux0 < 6.16unaffected
LinuxLinux6.18.36 <= 6.18.*unaffected
LinuxLinux7.0.13 <= 7.0.*unaffected
LinuxLinux7.1 <= *unaffected

Weaknesses

References