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, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)
References	DLA-4327-1, DLA-4328-1, DSA-6009-1

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)	5.10.244-1	fixed
	bookworm	6.1.148-1	vulnerable
	bookworm (security)	6.1.153-1	fixed
	trixie	6.12.43-1	fixed
	trixie (security)	6.12.48-1	fixed
	forky, sid	6.16.12-2	fixed
linux-6.1 (PTS)	bullseye (security)	6.1.153-1~deb11u1	fixed

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

Package	Type	Release	Fixed Version	Origin
linux	source	bullseye	5.10.244-1	DLA-4327-1
linux	source	bookworm	6.1.153-1	DSA-6009-1
linux	source	trixie	6.12.43-1
linux	source	(unstable)	6.16.3-1
linux-6.1	source	bullseye	6.1.153-1~deb11u1	DLA-4328-1

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