Linux 2.0.33 vulnerability: fragment patterns

From: Alan Cox (alanat_private)
Date: Thu Apr 16 1998 - 07:09:56 PDT

  • Next message: Thomas Roessler: "xdm problems" 

    Ok duplicated. There's an 'off by one IP header' bug

--- ip_fragment.c.old   Thu Apr 16 12:25:34 1998
+++ ip_fragment.c       Thu Apr 16 12:29:02 1998
@@ -375,7 +375,7 @@
        fp = qp->fragments;
        while(fp != NULL)
        {
-               if (fp->len < 0 || count+fp->len > skb->len)
+               if (fp->len < 0 || fp->offset+qp->ihlen+fp->len > skb->len)
                {
                        NETDEBUG(printk("Invalid fragment list: Fragment over size.\n"));
                        ip_free(qp);

    This archive was generated by hypermail 2b30 : Fri Apr 13 2001 - 13:49:24 PDT