CVE-2021-20194

Name	CVE-2021-20194
Description	There is a vulnerability in the linux kernel versions higher than 5.2 (if kernel compiled with config params CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY not set, and BPF hook to getsockopt is registered). As result of BPF execution, the local user can trigger bug in __cgroup_bpf_run_filter_getsockopt() function that can lead to heap overflow (because of non-hardened usercopy). The impact of attack could be deny of service or possibly privileges escalation.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, 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)	buster	4.19.249-2	fixed
	buster (security)	4.19.269-1	fixed
	bullseye	5.10.158-2	fixed
	bullseye (security)	5.10.162-1	fixed
	bookworm	6.1.15-1	fixed
	sid	6.1.20-1	fixed

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

Package	Type	Release	Fixed Version
linux	source	stretch	(not affected)
linux	source	buster	(not affected)
linux	source	(unstable)	5.10.19-1

Notes

[buster] - linux <not-affected> (Vulnerable code not present)
[stretch] - linux <not-affected> (Vulnerable code not present)
https://bugzilla.redhat.com/show_bug.cgi?id=1912683
https://patchwork.kernel.org/project/netdevbpf/patch/20210122164232.61770-1-loris.reiff@liblor.ch/#23921223