diff --git a/hw/ne2000.c b/hw/ne2000.c
index 674d83e490..e23c6df069 100644
--- a/hw/ne2000.c
+++ b/hw/ne2000.c
@@ -206,7 +206,7 @@ static int ne2000_buffer_full(NE2000State *s)
 
     index = s->curpag << 8;
     boundary = s->boundary << 8;
-    if (index < boundary)
+    if (index <= boundary)
         avail = boundary - index;
     else
         avail = (s->stop - s->start) - (index - boundary);