lxc-alpine: allow /dev/full

The template creates /dev/full for the container but needs also give
permission to access it.

Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>

templates/lxc-alpine.in

@@ -197,9 +197,10 @@ lxc.cap.drop = sys_module mac_admin mac_override sys_time
 
 # devices
 lxc.cgroup.devices.deny = a
-# /dev/null and zero
+# /dev/null, zero and full
 lxc.cgroup.devices.allow = c 1:3 rwm
 lxc.cgroup.devices.allow = c 1:5 rwm
+lxc.cgroup.devices.allow = c 1:7 rwm
 # consoles
 lxc.cgroup.devices.allow = c 5:1 rwm
 lxc.cgroup.devices.allow = c 5:0 rwm