clarification of additional section cve 2024-11187 ?

[Jeremy C. Reed]

"When answering queries, don't add data to the additional section if the 
answer has more than 13 names in the RDATA."

That is vague or misleading: is this saying don't add to additional 
section if the ANSWER SECTION has more than 13 separated "names" (so not 
limited by rrsets if have same names)? or is this the additional section 
only and nothing to do with "answer"?

Looking at code changes, I don't think this is about ANSWER 
(dns_rdataset_additionaldata) and is not about count of names either 
(dns_rdataset_count).

Maybe instead:

"When answering queries, don't add data to the Additional Section if it 
will have more than 13 records."

I didn't read closely nor test, but will it add up to 13 records in the 
Additional Section?

For example @f.root-servers.net for COM returns additional section of 26 
records (A and AAA glue), 13 names, and 13 rrsets. What happens with the 
new behavior? How will chop out the glue?

Also I see code change for checking for ANY, if this is a change of 
behavior, please consider also document if query is for ANY then no 
additional section. (I also didn't test this.)