stats: malformed entry when making NS . queries

[ainar-g]

Prerequisites

• I have checked the Wiki and Discussions and found no answer

• I have searched other issues and found no duplicates

• I want to report a bug and not ask a question or ask for help

• I have set up AdGuard Home correctly and configured clients to use it. (Use the Discussions for help with installing and configuring clients.)

Platform (OS and CPU architecture)

Linux/AMD64 (aka x86_64)

Installation

GitHub releases or script from README

Setup

On one machine

AdGuard Home version

v0.108.0-a.567+d3ada988

Action

1. dig IN NS .

2. Inspect the verbose logs.

Expected result

No errors, the query is recorded in the statistics.

Actual result

[debug] stats: malformed entry

Additional information and/or screenshots

It looks like Update receives an Entry with an empty domain name in this case, which makes it think that the domain name has always been empty, and that the entry is invalid. We should see if we can not trimming the domain name here and leave it to be . for such queries.

[ainar-g]

This also concerns the query log, where the query looks rather weird as well.

[Mizzick]

Please have a look, we have implemented the requested changes.
The new build v0.108.0-a.572+ca313521 has been published to the edge channel.