Description: vt_do_kdgkb_ioctl use-after-free
References:
 https://www.openwall.com/lists/oss-security/2020/10/16/1
 https://lore.kernel.org/lkml/20201016122412.31767-3-jslaby@suse.cz/
Notes:
 carnil> Fixed in 5.9.5.
Bugs:
upstream: released (5.10-rc2) [82e61c3909db51d91b9d3e2071557b6435018b80]
4.19-upstream-stable: released (4.19.155) [7e3ba72e5b9376e12839ea347c49fc4108244b0c]
4.9-upstream-stable: released (4.9.242) [04a6e5aa75e7a9432df0443a17ab7c8dd005cc9b]
sid: released (5.9.6-1)
4.19-buster-security: released (4.19.160-1)
4.9-stretch-security: released (4.9.246-1)