Qubes/core-agent-linux
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Fix iptables-restore race condition in vif-route-qubes

Browse Source 
In rare cases when vif-route-qubes is called simultaneously with some
other iptables-restore instance, it fails because of missing --wait (and
recent iptables-restore defaults to aborting instead of waiting
for lock). That other call may be from qubes-firewall or user script.

Related to QubesOS/qubes-issues#3665
This commit is contained in:
Marek Marczykowski-Górecki 2018-10-15 06:15:04 +02:00
parent 5ff462004a
commit 336754426b
No known key found for this signature in database
GPG Key ID: 063938BA42CFA724
1 changed files with 8 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
network/vif-route-qubes
View File

@ -25,7 +25,12 @@ dir=$(dirname "$0")
. "$dir/vif-common.sh" . "$dir/vif-common.sh"
#main_ip=$(dom0_ip) #main_ip=$(dom0_ip)
lockfile=/var/run/xen-hotplug/vif-lock
ipt_arg=
if "iptables-restore" --help 2>&1 | grep -q wait=; then
# 'wait' must be last on command line if secs not specified
ipt_arg=--wait
fi
# shellcheck disable=SC2154 # shellcheck disable=SC2154
if [ "${ip}" ]; then if [ "${ip}" ]; then
@ -101,12 +106,12 @@ if [ "${ip}" ] ; then
ipt=iptables-restore ipt=iptables-restore
fi fi
echo -e "*raw\n$iptables_cmd -i ${vif} ! -s ${addr} -j DROP\nCOMMIT" | \ echo -e "*raw\n$iptables_cmd -i ${vif} ! -s ${addr} -j DROP\nCOMMIT" | \
${cmdprefix} flock $lockfile $ipt --noflush ${cmdprefix} $ipt --noflush $ipt_arg
done done
# if no IPv6 is assigned, block all IPv6 traffic on that interface # if no IPv6 is assigned, block all IPv6 traffic on that interface
if ! [[ "$ip" = *:* ]]; then if ! [[ "$ip" = *:* ]]; then
echo -e "*raw\n$iptables_cmd -i ${vif} -j DROP\nCOMMIT" | \ echo -e "*raw\n$iptables_cmd -i ${vif} -j DROP\nCOMMIT" | \
${cmdprefix} flock $lockfile ip6tables-restore --noflush ${cmdprefix} ip6tables-restore --noflush $ipt_arg
fi fi
${cmdprefix} ip addr "${ipcmd}" "${back_ip}/32" dev "${vif}" ${cmdprefix} ip addr "${ipcmd}" "${back_ip}/32" dev "${vif}"
if [ "${back_ip6}" ] && [[ "${back_ip6}" != "fe80:"* ]]; then if [ "${back_ip6}" ] && [[ "${back_ip6}" != "fe80:"* ]]; then