"overdrop"+released patch

From: Aleph One (aleph1at_private)
Date: Mon Apr 20 1998 - 11:17:58 PDT

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    ---------- Forwarded message ----------
    Date: Sat, 18 Apr 1998 17:55:32 +0000 (WAT)
    From: NYIsles <NYIslesat_private>
    To: aleph1at_private
    Subject: "overdrop"+released patch
    
    Hey.. I don't know whether or not you've seen this but its at
    www.rootshell.com so i'm assuming you know about it... following the
    syndrop kernel bug was the 'overdrop' bug, which was merely just an
    annoyance for anyone at console.. however, the patched released to fix it
    made this change starting at line 346 (others might be diff. depending on
    any modifications) in net/ipv4/ip_fragment.c:
            if(len>65535)
            {
                    NETDEBUG(printk("Oversized IP packet from %s.\n", in_ntoa(qp->iph->saddr)));
                    ip_statistics.IpReasmFails++;
                    ip_free(qp);
                    return NULL;
            }
    
    The change made was simply to add a NETDEBUG() around the printk.
    Evidently, this was the wrong printk, and this little patch did not fix
    the problem. The correct one is on line 492 (but as i said, others' may be
    a little different):
    
            if(ntohs(iph->tot_len)+(int)offset>65535)
            {
                    skb->sk = NULL;
                    printk("Oversized packet received from %s\n",in_ntoa(iph->saddr));
                    kfree_skb(skb, FREE_READ);
                    ip_statistics.IpReasmFails++;
                    return NULL;
            }
    
    The fix is to simply add a NETDEBUG() around the printk, making it:
    
    NETDEBUG(printk("Oversized packet received from %s\n",in_ntoa(iph->saddr)));
    
    and viola, no more overdrop annoyance :> Sorry for wasting your time if
    someone has already told you about this. Regards,
            Paul McGovern
            NYIsleS@Xnet
    



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