From 9abdf580d910e13ade68cbb23da9b5d83b839f8d Mon Sep 17 00:00:00 2001 From: Felix Fietkau <nbd@openwrt.org> Date: Thu, 26 Oct 2006 01:33:36 +0000 Subject: [PATCH] use lock to remove race conditions in bringing up ppp and dhcp that would lead to multiple active processes SVN-Revision: 5298 --- package/base-files/default/lib/network/config.sh | 7 ++++++- package/base-files/default/sbin/ifdown | 14 ++++++++++++-- package/ppp/files/ppp.sh | 10 ++++++++-- 3 files changed, 26 insertions(+), 5 deletions(-) diff --git a/package/base-files/default/lib/network/config.sh b/package/base-files/default/lib/network/config.sh index 25c7278e99..9c91a7cabf 100755 --- a/package/base-files/default/lib/network/config.sh +++ b/package/base-files/default/lib/network/config.sh @@ -121,8 +121,12 @@ setup_interface() { ;; dhcp) # prevent udhcpc from starting more than once + lock "/var/lock/dhcp-$iface" pid="$(cat "$pidfile" 2>/dev/null)" - [ -d "/proc/$pid" ] && grep udhcpc "/proc/${pid}/cmdline" >/dev/null 2>/dev/null && return 0 + [ -d "/proc/$pid" ] && grep udhcpc "/proc/${pid}/cmdline" >/dev/null 2>/dev/null && { + lock -u "/var/lock/dhcp-$iface" + return 0 + } config_get ipaddr "$config" ipaddr config_get netmask "$config" netmask @@ -135,6 +139,7 @@ setup_interface() { # don't stay running in background if dhcp is not the main proto on the interface (e.g. when using pptp) [ "$proto1" != "$proto" ] && dhcpopts="-n -q" $DEBUG udhcpc -i "$iface" ${ipaddr:+-r $ipaddr} ${hostname:+-H $hostname} -b -p "$pidfile" ${dhcpopts:- -R &} + lock -u "/var/lock/dhcp-$iface" ;; *) if ( eval "type setup_interface_$proto" ) >/dev/null 2>/dev/null; then diff --git a/package/base-files/default/sbin/ifdown b/package/base-files/default/sbin/ifdown index 37d0918e85..50d59d1df8 100755 --- a/package/base-files/default/sbin/ifdown +++ b/package/base-files/default/sbin/ifdown @@ -12,14 +12,24 @@ debug "### ifdown $cfg ###" config_get proto "$cfg" proto [ -z "$proto" ] && { echo "interface not found."; exit; } +# make sure all locks are removed +for lock in "/var/lock/dhcp-$iface" "/var/lock/ppp-$iface"; do + [ -f "$lock" ] && { + lock -u "$lock" + sleep 1 + } +done + # kill active ppp daemon and other processes config_get ifname "$cfg" ifname pids="$(cat /var/run/${ifname}.pid /var/run/ppp-${cfg}.pid 2>/dev/null)" for pid in $pids; do [ -d "/proc/$pid" ] && { kill $pid - sleep 1 - [ -d "/proc/$pid" ] && kill -9 $pid + [ -d "/proc/$pid" ] && { + sleep 1 + kill -9 $pid 2>/dev/null >/dev/null + } } done rm -f /var/run/${ifname}.pid /var/run/ppp-${cfg}.pid diff --git a/package/ppp/files/ppp.sh b/package/ppp/files/ppp.sh index 133400509c..35572a0a0d 100644 --- a/package/ppp/files/ppp.sh +++ b/package/ppp/files/ppp.sh @@ -7,10 +7,14 @@ scan_ppp() { start_pppd() { local cfg="$1"; shift - + # make sure only one pppd process is started + lock "/var/lock/ppp-${cfg}" local pid="$(cat /var/run/ppp-${cfg}.pid 2>/dev/null)" - [ -d "/proc/$pid" ] && grep pppd "/proc/$pid/cmdline" 2>/dev/null >/dev/null && return 0 + [ -d "/proc/$pid" ] && grep pppd "/proc/$pid/cmdline" 2>/dev/null >/dev/null && { + lock -u "/var/lock/ppp-${cfg}" + return 0 + } config_get device "$cfg" device config_get unit "$cfg" unit @@ -31,4 +35,6 @@ start_pppd() { ${username:+user "$username" password "$password"} \ linkname "$cfg" \ ipparam "$cfg" + + lock -u "/var/lock/ppp-${cfg}" } -- 2.30.2