Acked-by: Peter Müller <peter.mueller(a)ipfire.org>

> The firewall engine generated rules that did not have any traffic
> selectors due to an improperly initialized variable in the source.
> 
> Signed-off-by: Michael Tremer <michael.tremer(a)ipfire.org>
> ---
>  config/firewall/rules.pl | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/config/firewall/rules.pl b/config/firewall/rules.pl
> index 30ad20df1..1b628df16 100644
> --- a/config/firewall/rules.pl
> +++ b/config/firewall/rules.pl
> @@ -401,6 +401,9 @@ sub buildrules {
>  					$source = "";
>  				}
>  
> +				# Make sure that $source is properly defined
> +				next unless (defined $source);
> +
>  				my $source_intf = @$src[1];
>  
>  				foreach my $dst (@destinations) {