CVE-2025-39742

Name	CVE-2025-39742
Description	In the Linux kernel, the following vulnerability has been resolved: RDMA: hfi1: fix possible divide-by-zero in find_hw_thread_mask() The function divides number of online CPUs by num_core_siblings, and later checks the divider by zero. This implies a possibility to get and divide-by-zero runtime error. Fix it by moving the check prior to division. This also helps to save one indentation level.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, 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	vulnerable
	bullseye (security)	5.10.237-1	vulnerable
	bookworm	6.1.148-1	vulnerable
	bookworm (security)	6.1.147-1	vulnerable
	trixie	6.12.43-1	fixed
	trixie (security)	6.12.41-1	vulnerable
	forky	6.16.3-1	fixed
	sid	6.16.7-1	fixed

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
linux	source	trixie	6.12.43-1
linux	source	(unstable)	6.16.3-1

https://git.kernel.org/linus/59f7d2138591ef8f0e4e4ab5f1ab674e8181ad3a (6.17-rc1)