CVE-2026-53164

Name	CVE-2026-53164
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
linux (PTS)	bullseye	5.10.223-1	fixed
	bullseye (security)	5.10.259-1	fixed
	bookworm, bookworm (security)	6.1.176-1	fixed
	trixie	6.12.94-1	fixed
	trixie (security)	6.12.95-1	fixed
	forky, sid	7.1.3-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version
linux	source	bullseye	(not affected)
linux	source	bookworm	(not affected)
linux	source	trixie	(not affected)
linux	source	(unstable)	7.0.13-1

Notes

[trixie] - linux <not-affected> (Vulnerable code not present)
[bookworm] - linux <not-affected> (Vulnerable code not present)
[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/6ec91df8aff77e2e8fe3179c1f3fc15b43a40ba3 (7.1)