--- nstx_pstack.c.orig
+++ nstx_pstack.c
@@ -49,7 +49,7 @@
    char *netpacket;
    int netpacketlen;
    
-   if ((!ptr) || len < sizeof(struct nstxhdr))
+   if ((!ptr) || (signed int) len < (signed int) sizeof(struct nstxhdr))
      return;
 
    if (!nstxpkt->id)