1.1 --- a/src/devices/emu/emu-net-device.cc	Wed Jul 08 21:45:23 2009 -0700
     1.2 +++ b/src/devices/emu/emu-net-device.cc	Fri Jul 10 09:50:24 2009 -0700
     1.3 @@ -612,6 +612,19 @@
     1.4    Ptr<Packet> originalPacket = packet->Copy ();
     1.5  
     1.6    EthernetHeader header (false);
     1.7 +
     1.8 +  //
     1.9 +  // This device could be running in an environment where completely unexpected
    1.10 +  // kinds of packets are flying around, so we need to harden things a bit and
    1.11 +  // filter out packets we think are completely bogus, so we always check to see
    1.12 +  // that the packet is long enough to contain the header we want to remove.
    1.13 +  //
    1.14 +  if (packet->GetSize() < header.GetSerializedSize())
    1.15 +    {
    1.16 +      m_phyRxDropTrace (originalPacket);
    1.17 +      return;
    1.18 +    }
    1.19 +
    1.20    packet->RemoveHeader (header);
    1.21  
    1.22    NS_LOG_LOGIC ("Pkt source is " << header.GetSource ());
    1.23 @@ -628,6 +641,16 @@
    1.24    if (header.GetLengthType () <= 1500)
    1.25      {
    1.26        LlcSnapHeader llc;
    1.27 +      //
    1.28 +      // Check to see that the packet is long enough to possibly contain the
    1.29 +      // header we want to remove before just naively calling.
    1.30 +      //
    1.31 +      if (packet->GetSize() < llc.GetSerializedSize())
    1.32 +        {
    1.33 +          m_phyRxDropTrace (originalPacket);
    1.34 +          return;
    1.35 +        }
    1.36 +
    1.37        packet->RemoveHeader (llc);
    1.38        protocol = llc.GetType ();
    1.39      }