commit 7c84ef0790275b20085c4f2f5d6543da4fa9cb27
from: Stefan Sperling <stsp@stsp.name>
date: Sun Aug 29 19:50:57 2021 UTC

reject port number zero

commit - f1cacac799e48da059d50c727b25d240483bed12
commit + 7c84ef0790275b20085c4f2f5d6543da4fa9cb27
blob - b22c70ab9a554f6e0b28eacc450bfd4f8deaa056
blob + dba94813bce80f3ec22679fe997ba51bbdfc8c58
--- libexec/got-read-gotconfig/parse.y
+++ libexec/got-read-gotconfig/parse.y
@@ -535,7 +535,7 @@ getservice(char *n)
 	u_long		 ulval;
 
 	if (atoul(n, &ulval) == 0) {
-		if (ulval > 65535) {
+		if (ulval == 0 || ulval > 65535) {
 			yyerror("illegal port value %lu", ulval);
 			return (-1);
 		}