CVE-2025-40293

Name	CVE-2025-40293
Description	In the Linux kernel, the following vulnerability has been resolved: iommufd: Don't overflow during division for dirty tracking If pgshift is 63 then BITS_PER_TYPE(bitmap->bitmap) pgsize will overflow to 0 and this triggers divide by 0. In this case the index should just be 0, so reorganize things to divide by shift and avoid hitting any overflows.
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)	5.10.247-1	fixed
	bookworm	6.1.148-1	vulnerable
	bookworm (security)	6.1.158-1	vulnerable
	trixie	6.12.57-1	vulnerable
	trixie (security)	6.12.48-1	vulnerable
	forky	6.17.9-1	fixed
	sid	6.17.11-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
linux	source	bullseye	(not affected)
linux	source	(unstable)	6.17.8-1

[bullseye] - linux <not-affected> (Vulnerable code not present)
https://git.kernel.org/linus/cb30dfa75d55eced379a42fd67bd5fb7ec38555e (6.18-rc5)