Log error if we try and use netlink in a child process.

Child processes to handle TCP connections don't
have an open netlink socket. If they call
iface_enumerate() that's a bug.

src/dbus.c

@@ -654,7 +654,7 @@ static DBusMessage *dbus_add_lease(DBusMessage* message)
 
 static DBusMessage *dbus_del_lease(DBusMessage* message)
 {
-  struct dhcp_lease *lease;
+  struct dhcp_lease *lease = NULL;
   DBusMessageIter iter;
   const char *ipaddr;
   DBusMessage *reply;
@@ -672,10 +672,10 @@ static DBusMessage *dbus_del_lease(DBusMessage* message)
    
   dbus_message_iter_get_basic(&iter, &ipaddr);
 
-  if (inet_pton(AF_INET, ipaddr, &addr.addr4))
+  if (inet_pton(AF_INET, ipaddr, &addr.addr4) && daemon->dhcp)
     lease = lease_find_by_addr(addr.addr4);
 #ifdef HAVE_DHCP6
-  else if (inet_pton(AF_INET6, ipaddr, &addr.addr6))
+  else if (inet_pton(AF_INET6, ipaddr, &addr.addr6) && daemon->doing_dhcp6)
     lease = lease6_find_by_addr(&addr.addr6, 128, 0);
 #endif
   else

src/dnsmasq.c

@@ -127,6 +127,7 @@ int main (int argc, char **argv)
      This might be increased is EDNS packet size if greater than the minimum. */ 
   daemon->packet_buff_sz = daemon->edns_pktsz + MAXDNAME + RRFIXEDSZ;
   daemon->packet = safe_malloc(daemon->packet_buff_sz);
+  daemon->pipe_to_parent = -1;
   
   if (option_bool(OPT_EXTRALOG))
     daemon->addrbuff2 = safe_malloc(ADDRSTRLEN);
@@ -1080,8 +1081,6 @@ int main (int argc, char **argv)
   
   pid = getpid();
 
-  daemon->pipe_to_parent = -1;
-
 #ifdef HAVE_INOTIFY
   /* Using inotify, have to select a resolv file at startup */
   poll_resolv(1, 0, now);

src/netlink.c

@@ -165,6 +165,13 @@ int iface_enumerate(int family, void *parm, callback_t callback)
     struct rtgenmsg g; 
   } req;
 
+  /* The netlink socket is not available in child processes. */
+  if (daemon->pipe_to_parent != -1)
+    {
+      my_syslog(LOG_ERR, _("BUG: called iface_enumerate() in child process"));
+      return 0;
+    }
+  
   memset(&req, 0, sizeof(req));
   memset(&addr, 0, sizeof(addr));