Update judge/runguard.cc

Co-authored-by: Jaap Eldering <[email protected]>

Author: meisterT

judge/runguard.cc

@@ -826,7 +826,7 @@ void setrestrictions()
 	/* Set group-id (must be root for this, so before setting user). */
 	if ( use_group ) {
 		if ( setgid(rungid) ) error(errno,"cannot set group ID to `%d'",rungid);
-		gid_t aux_groups[10];
+		gid_t aux_groups[1];
 		aux_groups[0] = rungid;
 		if ( setgroups(1, aux_groups) ) error(errno,"cannot clear auxiliary groups");