4 files changed, 43 insertions, 27 deletions
diff --git a/package/base-files/Makefile b/package/base-files/Makefile
index 8eca0d5dda..90c804bbe2 100644
--- a/package/base-files/Makefile
+++ b/package/base-files/Makefile
@@ -10,7 +10,7 @@ include $(TOPDIR)/rules.mk
 include $(INCLUDE_DIR)/kernel.mk
 
 PKG_NAME:=base-files
-PKG_RELEASE:=46
+PKG_RELEASE:=47
 
 PKG_FILE_DEPENDS:=$(PLATFORM_DIR)/ $(GENERIC_PLATFORM_DIR)/base-files/
 
diff --git a/package/base-files/files/lib/network/config.sh b/package/base-files/files/lib/network/config.sh
index 32170bb274..1bb3a46ecd 100755
--- a/package/base-files/files/lib/network/config.sh
+++ b/package/base-files/files/lib/network/config.sh
@@ -70,6 +70,16 @@ add_vlan() {
 add_dns() {
 	local cfg="$1"; shift
 
+	remove_dns "$cfg"
+
+	# We may be called by pppd's ip-up which has a nonstandard umask set.
+	# Create an empty file here and force its permission to 0644, otherwise
+	# dnsmasq will not be able to re-read the resolv.conf.auto .
+	[ ! -f /tmp/resolv.conf.auto ] && {
+		touch /tmp/resolv.conf.auto
+		chmod 0644 /tmp/resolv.conf.auto
+	}
+
 	local dns
 	local add
 	for dns in "$@"; do
@@ -79,20 +89,27 @@ add_dns() {
 		}
 	done
 
-	uci_set_state network "$cfg" dns "$add"
+	[ -n "$cfg" ] && {
+		uci_set_state network "$cfg" dns "$add"
+		uci_set_state network "$cfg" resolv_dns "$add"
+	}
 }
 
 # remove dns entries of the given iface
 remove_dns() {
 	local cfg="$1"
 
-	local dns
-	config_get dns "$cfg" dns
-	for dns in $dns; do
-		sed -i -e "/^nameserver $dns$/d" /tmp/resolv.conf.auto
-	done
+	[ -n "$cfg" ] && {
+		[ -f /tmp/resolv.conf.auto ] && {
+			local dns=$(uci_get_state network "$cfg" resolv_dns)
+			for dns in $dns; do
+				sed -i -e "/^nameserver $dns$/d" /tmp/resolv.conf.auto
+			done
+		}
 
-	uci_revert_state network "$cfg" dns
+		uci_revert_state network "$cfg" dns
+		uci_revert_state network "$cfg" resolv_dns
+	}
 }
 
 # sort the device list, drop duplicates
@@ -212,13 +229,7 @@ setup_interface_static() {
 	[ -z "$ip6addr" ] || $DEBUG ifconfig "$iface" add "$ip6addr"
 	[ -z "$gateway" ] || $DEBUG route add default gw "$gateway" dev "$iface"
 	[ -z "$ip6gw" ] || $DEBUG route -A inet6 add default gw "$ip6gw" dev "$iface"
-	[ -z "$dns" ] || {
-		for ns in $dns; do
-			grep "$ns" /tmp/resolv.conf.auto 2>/dev/null >/dev/null || {
-				echo "nameserver $ns" >> /tmp/resolv.conf.auto
-			}
-		done
-	}
+	[ -z "$dns" ] || add_dns "$config" $dns
 
 	config_get type "$config" TYPE
 	[ "$type" = "alias" ] && return 0
@@ -363,12 +374,14 @@ setup_interface() {
 stop_interface_dhcp() {
 	local config="$1"
 
-	local iface
+	local ifname
 	config_get ifname "$config" ifname
 
 	local lock="/var/lock/dhcp-${ifname}"
 	[ -f "$lock" ] && lock -u "$lock"
 
+	remove_dns "$config"
+
 	local pidfile="/var/run/dhcp-${ifname}.pid"
 	local pid="$(cat "$pidfile" 2>/dev/null)"
 	[ -d "/proc/$pid" ] && {
diff --git a/package/base-files/files/sbin/ifdown b/package/base-files/files/sbin/ifdown
index 7c6a5b7061..92cdfd2b02 100755
--- a/package/base-files/files/sbin/ifdown
+++ b/package/base-files/files/sbin/ifdown
@@ -40,6 +40,9 @@ done
 config_get iftype "$cfg" type
 [ "bridge" = "$iftype" ] && brctl delbr "$ifname" >/dev/null 2>/dev/null
 
+# remove the interface's dns entries
+remove_dns "$cfg"
+
 # remove the interface's network state
 uci_revert_state network "$1"
 
diff --git a/package/base-files/files/usr/share/udhcpc/default.script b/package/base-files/files/usr/share/udhcpc/default.script
index ceabf4bf3a..39527778ad 100755
--- a/package/base-files/files/usr/share/udhcpc/default.script
+++ b/package/base-files/files/usr/share/udhcpc/default.script
@@ -139,21 +139,21 @@ setup_interface () {
 	}
 
 	# DNS
-	config_get old_dns "$ifc" dns
+	old_dns=$(uci_get_state network "$ifc" dns)
+	old_domain=$(uci_get_state network "$ifc" dnsdomain)
 	user_dns=$(uci_get "network.$ifc.dns")
 	[ -n "$user_dns" ] && dns="$user_dns"
 
-	[ -n "$dns" ] && [ ! -s "${RESOLV_CONF}" -o "$dns" != "$old_dns" ] && {
+	[ -n "$dns" ] && [ "$dns" != "$old_dns" -o -n "$user_dns" ] && {
 		echo "udhcpc: setting dns servers: $dns"
-		echo -n > "${RESOLV_CONF}.tmp"
-		for i in $dns ; do
-			echo "nameserver $i" >> "${RESOLV_CONF}.tmp"
-		done
-		${domain:+echo search $domain} >> "${RESOLV_CONF}.tmp"
-		mv "${RESOLV_CONF}.tmp" "$RESOLV_CONF"
-
-		change_state network "$ifc" dnsdomain "$domain"
-		change_state network "$ifc" dns "$dns"
+		add_dns "$ifc" $dns
+
+		[ -n "$domain" ] && [ "$domain" != "$old_domain" ] && {
+			echo "udhcpc: setting dns domain: $domain"
+			sed -i -e "${old_domain:+/^search $old_domain$/d; }/^search $domain$/d" "${RESOLV_CONF}"
+			echo "search $domain" >> "${RESOLV_CONF}"
+			change_state network "$ifc" dnsdomain "$domain"
+		}
 	}
 
 	[ -n "$ifc" ] || return