Re: [patches] [bug] when /etc/hosts doesn't exist, apt fails to resolve hostnames using libc6 2.10.1

[Steve Langasek <steve.langasek@xxxxxxxxxx>]

On Wed, Aug 5, 2009 at 14:35:26 +0200, Aurelien Jarno wrote:

> The patch below should fix this problem:

> diff --git a/nss/nss_files/files-hosts.c b/nss/nss_files/files-hosts.c
> index 7b69d47..e6e4576 100644
> --- a/nss/nss_files/files-hosts.c
> +++ b/nss/nss_files/files-hosts.c
> @@ -423,6 +423,11 @@ _nss_files_gethostbyname4_r (const char *name, struct gaih_addrtuple **pat,
>        if (! keep_stream)
> 	internal_endent ();
>      }
> +  else
> +    {
> +       *errnop = errno;
> +       *herrnop = NETDB_INTERNAL;
> +    }
>  
>    __libc_lock_unlock (lock);
> 

In testing here, it appears that NETDB_INTERNAL is not the correct herrno to
set - at least, getaddrinfo() interprets this as a system failure.  Setting
it to NO_DATA instead is sufficient to get getaddrinfo() working here with a
missing /etc/hosts.

It also seems like the logical value to return, so I don't imagine this will
introduce regressions, but I haven't tested very extensively yet.

Cheers,
-- 
Steve Langasek                   Give me a lever long enough and a Free OS
Debian Developer                   to set it on, and I can move the world.
Ubuntu Developer                                    http://www.debian.org/
slangasek@xxxxxxxxxx                                     vorlon@xxxxxxxxxx