Comment 138 for bug 1945590

Indeed -27 does not contain the fix.

We can find the release notes for specific package in https://launchpad.net/ubuntu/+source/linux (in this case https://launchpad.net/ubuntu/+source/linux/5.13.0-27.29), and see if it contains the relevant patch. For this bug, we should find a line with "elantech", probably like this:

`Input: elantech - fix stack out of bound access in elantech_change_report_id()`

Also, thanks @bttksz for pointing to the kernel-team PPA :-)

I was not finding up-to-date "master-next" kernels to try, since it appears they were removed from ubuntu-proposed, but now I can use this to easily check for upcoming kernels (already have -28 there). To set it up I used:

1. `sudo add-apt-repository ppa:canonical-kernel-team/ppa`

2. Since I want to avoid auto-installing the packages from there, and just have them available for manual installation, I also set low priority to this repo:
```
cat >/etc/apt/preferences.d/ubuntu-kernel-ppa-updates <<EOF
# Configure apt for manual-only installs of packages from kernel-team-ppa
Package: *
Pin: release o=LP-PPA-canonical-kernel-team
Pin-Priority: 70
EOF
```