Subject: kern/8305: inet6: ndp gets confused on alpha
To: None <gnats-bugs@gnats.netbsd.org>
From: Bill Sommerfeld <sommerfeld@orchard.arlington.ma.us>
List: netbsd-bugs
Date: 08/31/1999 22:09:54
>Number: 8305
>Category: kern
>Synopsis: inet6: ndp gets confused on alpha
>Confidential: no
>Severity: serious
>Priority: medium
>Responsible: kern-bug-people (Kernel Bug People)
>State: open
>Class: sw-bug
>Submitter-Id: net
>Arrival-Date: Tue Aug 31 21:50:01 1999
>Last-Modified:
>Originator: Bill Sommerfeld
>Organization:
>Release: 19990831
>Environment:
alpha pc164 running -current.
>Description:
`ndp -an' output is confused on alpha:
Neighbor Linklayer Address Netif Expire St Flgs Prbs
ndp: ioctl: Device not configured
ndp: failed to get neighbor information
fe80:1::210:4bff:fe9d:5b5f 0:0:18:12:3:0 (null)
ndp: ioctl: Device not configured
ndp: failed to get neighbor information
fe80:1::2e0:29ff:fe47:b485 0:0:18:12:1:0 (null)
ndp: ioctl: Device not configured
ndp: failed to get neighbor information
fe80:1::a00:2bff:fe81:6007 0:0:18:12:1:0 (null)
>How-To-Repeat:
run `ndp -an'
>Fix:
???
from looking at src/usr.sbin/ndp/ndp.c, it looks like the
program's expecting to find the routing table entries returned
via sysctl as an rtm header, followed by two sockaddrs.
rtm = (struct rt_msghdr *)next;
sin = (struct sockaddr_in6 *)(rtm + 1);
sdl = (struct sockaddr_dl *)(sin + 1);
However, when inspecting the actual block of memory returned by the
kernel, i find an extra 4 bytes (containing 0xdeadbeef) stuck in
between the two sockaddrs; when running under a debugger, manually
moving sdl 4 bytes later inside dump() causes the expected output to
look sane.
>Audit-Trail:
>Unformatted: