Description: vt: keyboard: avoid signed integer overflow in k_ascii
References:
 https://lkml.org/lkml/2020/3/22/482
Notes:
Bugs:
upstream: released (5.8-rc1) [b86dab054059b970111b5516ae548efaae5b3aae]
4.19-upstream-stable: released (4.19.128) [18059925dbb6a7b6be1c0166ecca29d6b7977c9a]
4.9-upstream-stable: released (4.9.227) [adf823fa2a53db5d119d90817778f263a3a47608]
3.16-upstream-stable: ignored "EOL"
sid: released (5.7.6-1)
4.19-buster-security: released (4.19.131-1)
4.9-stretch-security: released (4.9.228-1)
3.16-jessie-security: ignored "EOL"