CVE-2021-47500

Name	CVE-2021-47500
Description	In the Linux kernel, the following vulnerability has been resolved: iio: mma8452: Fix trigger reference couting The mma8452 driver directly assigns a trigger to the struct iio_dev. The IIO core when done using this trigger will call `iio_trigger_put()` to drop the reference count by 1. Without the matching `iio_trigger_get()` in the driver the reference count can reach 0 too early, the trigger gets freed while still in use and a use-after-free occurs. Fix this by getting a reference to the trigger before assigning it to the IIO device.
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)	jessie, jessie (lts)	3.16.84-1	vulnerable
	stretch (security)	4.9.320-2	vulnerable
	stretch (lts), stretch	4.9.320-3	vulnerable
	buster (security), buster, buster (lts)	4.19.316-1	fixed
	bullseye	5.10.223-1	fixed
	bullseye (security)	5.10.226-1	fixed
	bookworm	6.1.115-1	fixed
	bookworm (security)	6.1.112-1	fixed
	trixie	6.11.7-1	fixed
	sid	6.11.9-1	fixed

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

Package	Type	Release	Fixed Version	Urgency
linux	source	jessie	(unfixed)	end-of-life
linux	source	stretch	(unfixed)	end-of-life
linux	source	buster	4.19.232-1
linux	source	bullseye	5.10.92-1
linux	source	(unstable)	5.15.15-1

https://git.kernel.org/linus/cd0082235783f814241a1c9483fb89e405f4f892 (5.16-rc5)