Re: kern/43185: bpf_validate() uses BPF_RVAL() when it should use BPF_SRC()

[Guy Harris <guy%alum.mit.edu@localhost>]

The following reply was made to PR kern/43185; it has been noted by GNATS.

From: Guy Harris <guy%alum.mit.edu@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: kern-bug-people%netbsd.org@localhost, gnats-admin%netbsd.org@localhost, 
netbsd-bugs%netbsd.org@localhost
Subject: Re: kern/43185: bpf_validate() uses BPF_RVAL() when it should use 
BPF_SRC()
Date: Wed, 21 Apr 2010 02:40:55 -0700

 On Apr 21, 2010, at 2:12 AM, Guy Harris wrote:
 
 > I don't have a NetBSD VM on which to try this, and I'm not sure why =
 I'm not getting a crash on my OpenBSD 4.2 VM (OpenBSD has the same bug), =
 but a live tcpdump capture with a filter of "link[0:4]/0 =3D 2" *should* =
 get the filter rejected:
 
        ...
 
 > but it doesn't (at least not on OpenBSD 4.2 - the NetBSD =
 bpf_validate() has the same code).
 
 It doesn't because
 
        1) I'm a moron and forgot that it actually needs to see network =
 traffic in order to try the filter
 
 and
 
        2) the virtual machine isn't on a particularly busy network, so =
 it wasn't getting any traffic.
 
 If I backgrounded tcpdump and then did a ping, crashorama.=