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    SubjectRe: Ping with a 65510 bytes pack
    On Sat, 19 Oct 1996, Jon Lewis wrote:

    > Could you just do something like this before trashing the packet?
    >
    > printk("Invalid packet received from %s\n",in_ntoa(skb->saddr));
    >
    > It would be interesting to log attempts to crash our systems.

    It doesn't seem to work, Jon. I put the line above before put the big
    packet in trash. Take a look on what I got ... The address returned seemd
    to be kind of randomic. It should be 200.18.234.2. And I have only issued
    two big pings ... why do the syslog points 3 attempts ?!

    Script started on Sat Oct 19 19:44:13 1996
    ZeTrovao:/var/log# tail syslog
    Oct 19 19:36:50 ZeTrovao kernel: NE*000 ethercard probe at 0x340: 00 40 05 19 8d 3c
    Oct 19 19:36:50 ZeTrovao kernel: eth0: NE2000 found at 0x340, using IRQ 5.
    Oct 19 19:36:50 ZeTrovao kernel: Partition check:
    Oct 19 19:36:50 ZeTrovao kernel: hda:Started kswapd v 1.4.2.2
    Oct 19 19:36:50 ZeTrovao kernel: hda1 hda2 hda3
    Oct 19 19:36:50 ZeTrovao kernel: VFS: Mounted root (ext2 filesystem) readonly.
    Oct 19 19:36:50 ZeTrovao kernel: Adding Swap: 16124k swap-space
    Oct 19 19:42:53 ZeTrovao kernel: Invalid packet size received from 0.240.155.0
    Oct 19 19:43:12 ZeTrovao kernel: Invalid packet size received from 0.240.155.0
    Oct 19 19:44:00 ZeTrovao kernel: Invalid packet size received from 108.109.110.111
    ZeTrovao:/var/log# exit
    exit

    Script done on Sat Oct 19 19:44:29 1996

    Here is what I did in ip_fragment.c:

    /*
    * Attempt to construct an oversize packet.
    */

    if(ntohs(iph->tot_len)+(int)offset>65535)
    {
    printk("Invalid packet size received from %s\n",in_ntoa(skb->saddr));
    skb->sk = NULL;
    frag_kfree_skb(skb, FREE_READ);
    ip_statistics.IpReasmFails++;
    return NULL;
    }

    /*
    * Determine the position of this fragment.
    */


    Is there anything wrong ?!

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