From a39ddff4287e760f44a2d7bb44be364a0061d4bf Mon Sep 17 00:00:00 2001 From: Hans Dedecker Date: Thu, 7 Dec 2017 10:11:50 +0100 Subject: [PATCH] dnsmasq: write atomic host file Different invocations of the dnsmasq init script (e.g. at startup by procd) will rewrite the dhcp host file which might result into dnsmasq reading an empty dhcp host file as it is being rewritten by the dnsmasq init script. Let the dnsmasq init script first write to a temp dhcp host file so it does not overwrite the contents of the existing dhcp host file. Reported-by: Hartmut Birr Signed-off-by: Hans Dedecker --- package/network/services/dnsmasq/Makefile | 2 +- package/network/services/dnsmasq/files/dnsmasq.init | 8 +++++--- 2 files changed, 6 insertions(+), 4 deletions(-) diff --git a/package/network/services/dnsmasq/Makefile b/package/network/services/dnsmasq/Makefile index 480a8a9f48..59beb98a56 100644 --- a/package/network/services/dnsmasq/Makefile +++ b/package/network/services/dnsmasq/Makefile @@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk PKG_NAME:=dnsmasq PKG_VERSION:=2.78 -PKG_RELEASE:=5 +PKG_RELEASE:=6 PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.xz PKG_SOURCE_URL:=http://thekelleys.org.uk/dnsmasq/ diff --git a/package/network/services/dnsmasq/files/dnsmasq.init b/package/network/services/dnsmasq/files/dnsmasq.init index 8c40f3b59a..b84f531ac0 100644 --- a/package/network/services/dnsmasq/files/dnsmasq.init +++ b/package/network/services/dnsmasq/files/dnsmasq.init @@ -294,7 +294,7 @@ dhcp_host_add() { config_get_bool dns "$cfg" dns 0 [ "$dns" = "1" -a -n "$ip" -a -n "$name" ] && { - echo "$ip $name${DOMAIN:+.$DOMAIN}" >> $HOSTFILE + echo "$ip $name${DOMAIN:+.$DOMAIN}" >> $HOSTFILE_TMP } config_get mac "$cfg" mac @@ -635,7 +635,7 @@ dhcp_domain_add() { record="${record:+$record }$name" done - echo "$ip $record" >> $HOSTFILE + echo "$ip $record" >> $HOSTFILE_TMP } dhcp_srv_add() { @@ -741,6 +741,7 @@ dnsmasq_start() CONFIGFILE="${BASECONFIGFILE}.${cfg}" CONFIGFILE_TMP="${CONFIGFILE}.$$" HOSTFILE="${BASEHOSTFILE}.${cfg}" + HOSTFILE_TMP="${HOSTFILE}.$$" BASEDHCPSTAMPFILE_CFG="${BASEDHCPSTAMPFILE}.${cfg}" # before we can call xappend @@ -751,7 +752,7 @@ dnsmasq_start() chown dnsmasq:dnsmasq /var/run/dnsmasq echo "# auto-generated config file from /etc/config/dhcp" > $CONFIGFILE_TMP - echo "# auto-generated config file from /etc/config/dhcp" > $HOSTFILE + echo "# auto-generated config file from /etc/config/dhcp" > $HOSTFILE_TMP local dnsmasqconffile="/etc/dnsmasq.${cfg}.conf" if [ ! -r "$dnsmasqconffile" ]; then @@ -998,6 +999,7 @@ dnsmasq_start() echo >> $CONFIGFILE_TMP mv -f $CONFIGFILE_TMP $CONFIGFILE + mv -f $HOSTFILE_TMP $HOSTFILE [ "$resolvfile" = "/tmp/resolv.conf.auto" ] && { rm -f /tmp/resolv.conf