Ensure dnsmasq can read updates to dnsmasq conffile.

1 files changed, 6 insertions, 1 deletions

diff --git a/nova/network/linux_net.py b/nova/network/linux_net.py
index 9d5bd8495..7d708968c 100644
--- a/nova/network/linux_net.py
+++ b/nova/network/linux_net.py
@@ -150,9 +150,14 @@ def update_dhcp(context, network_id):
     signal causing it to reload, otherwise spawn a new instance
     """
     network_ref = db.network_get(context, network_id)
-    with open(_dhcp_file(network_ref['vlan'], 'conf'), 'w') as f:
+
+    conffile = _dhcp_file(network_ref['vlan'], 'conf')
+    with open(conffile, 'w') as f:
         f.write(get_dhcp_hosts(context, network_id))
 
+    # Make sure dnsmasq can actually read it (it setuid()s to "nobody")
+    os.chmod(conffile, 0644)
+
     pid = _dnsmasq_pid_for(network_ref['vlan'])
 
     # if dnsmasq is already running, then tell it to reload