shadowsocks-libev: flush ss rules on entry

Fixes issue reported in openwrt/luci#2527

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

net/shadowsocks-libev/Makefile

@@ -14,7 +14,7 @@ include $(TOPDIR)/rules.mk
 #
 PKG_NAME:=shadowsocks-libev
 PKG_VERSION:=3.2.3
-PKG_RELEASE:=3
+PKG_RELEASE:=4
 
 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.gz
 PKG_SOURCE_URL:=https://github.com/shadowsocks/shadowsocks-libev/releases/download/v$(PKG_VERSION)

net/shadowsocks-libev/files/shadowsocks-libev.init

@@ -144,12 +144,15 @@ ss_rules() {
 	local args
 
 	[ -x "$bin" ] || return 1
+	"$bin" -f
+	"$bin" -f -6
+
 	config_get cfgtype "$cfg" TYPE
 	[ "$cfgtype" = ss_rules ] || return 1
 
 	eval "$(validate_ss_rules_section "$cfg" ss_validate_mklocal)"
 	validate_ss_rules_section "$cfg" || return 1
-	[ "$disabled" = 0 ] || return 1
+	[ "$disabled" = 0 ] || return 0
 
 	eval local_port_tcp="\$ss_rules_redir_tcp_$redir_tcp"
 	eval local_port_udp="\$ss_rules_redir_udp_$redir_udp"