Date: Tue, 1 Jun 1999 23:30:33 +0100
From: Alan Cox <alan@LXORGUK.UKUU.ORG.UK>
To: BUGTRAQ@netspace.org
Subject: Linux 2.2 DoS attack
Ok problem confirmed. Its not icmp however - in fact the program given
has some bugs that cause it. If it had been a correctly written icmp tester
it wouldnt have worked. A blessing in disguise.
Anyway the fix seems to be this. Sorry it took so long to sort out.
--- ../linux.vanilla/net/ipv4/ip_options.c Wed May 12 16:49:38 1999
+++ net/ipv4/ip_options.c Tue Jun 1 22:11:46 1999
@@ -452,7 +452,6 @@
error:
if (skb) {
icmp_send(skb, ICMP_PARAMETERPROB, 0, htonl((pp_ptr-iph)<<24));
- kfree_skb(skb);
}
return -EINVAL;
}
Alan
