From: "Theo de Raadt" <deraadt@openbsd.org>
Subject: Re: The empty string is not a valid host name
To: tech@openbsd.org
Date: Sun, 21 Jun 2026 11:58:44 -0600

Florian and I have discussed this; it is not the right way to solve
the problem.

Florian Obser <florian@openbsd.org> wrote:

> On 2026-04-11 10:42 +02, Florian Obser <florian@openbsd.org> wrote:
> > I've spotted this while working on something else.
> >
> > OK?
> >
> 
> Going through diffs that didn't make release. OK?
> 
> diff --git lib/libc/net/res_comp.c lib/libc/net/res_comp.c
> index ce9f92ae771..43d50f93c2b 100644
> --- lib/libc/net/res_comp.c
> +++ lib/libc/net/res_comp.c
> @@ -348,6 +348,9 @@ __res_hnok(const char *dn)
>  {
>  	int pch = PERIOD, ch = *dn++;
>  
> +	if (ch == '\0')
> +		return (0);
> +
>  	while (ch != '\0') {
>  		int nch = *dn++;
>  
> 
> 
> -- 
> In my defence, I have been left unsupervised.
>