Subject: Re: ip->ip_len signed?
To: Tim Newsham <>
From: Jason Thorpe <>
List: tech-kern
Date: 10/24/1996 21:25:23
On Thu, 24 Oct 1996 15:58:56 -1000 (HST) 
 Tim Newsham <> wrote:

 >    I noticed this in an include file and it struck me
 > as odd:
 >   struct ip {
 >      ...
 >      int16_t ip_len;
 >      ...
 >    }
 > why is the length field signed?

IMO, this is a bug.  It keeps the kernel from being able to accept 
IP_MAXPACKET size packets.

I'm going to check in some changes in a little while which fix this
bug, and avoids cases where the ip_len field can overflow.  This is
the bug that causes the `death ping' problem that was recently

I don't have NetBSD-1.2 installed anywhere... if someone does, and would
like to test a patch for NetBSD-1.2, please send me private e-mail, and
we can try and get it into the first 1.2 Official Patch.

Jason R. Thorpe                             
NASA Ames Research Center                               Home: 408.866.1912
NAS: M/S 258-6                                          Work: 415.604.0935
Moffett Field, CA 94035                                Pager: 415.428.6939