diff --git a/extras/deprecated/ixge/ixge.c b/extras/deprecated/ixge/ixge.c
index 6ab79c9..471fbed 100644
--- a/extras/deprecated/ixge/ixge.c
+++ b/extras/deprecated/ixge/ixge.c
@@ -2605,10 +2605,12 @@
 
   old = r->filter_control;
 
-  if (flags & ETHERNET_INTERFACE_FLAG_ACCEPT_ALL)
+  if (flags == ETHERNET_INTERFACE_FLAG_ACCEPT_ALL)
     r->filter_control = old | (1 << 9) /* unicast promiscuous */ ;
-  else
+  else if (flags == ETHERNET_INTERFACE_FLAGS_DEFAULT_L3)
     r->filter_control = old & ~(1 << 9);
+  else
+    return ~0;
 
   return old;
 }