Re: CURRENT: ifconfig tap0 results in core dump

Peter Edwards wrote:
>>>% ifconfig tap0
>>>tap0: flags=8802<BROADCAST,SIMPLEX,MULTICAST> mtu 1500
>>>       inet6 fe80::2bd:9ff:fe7c:100%tap0 prefixlen 64 scopeid 0x5
>>>zsh: segmentation fault (core dumped)  ifconfig tap0
>>>
>>>
>>>I remember that ifconfig didn't dump core when my laptop ran CURRENT
>>>from a few months ago.
>>>
>>
>>You'll probably need to build a version of ifconfig with debugging
>>symbols. And then provide a backtrace of the core dump.
>>
>>How soon after killing openvpn, do you use the ifconfig command.  It
>>might be possible that devfs was in the process of removing tap0, when
>>you used the ifconfig command.
>>
> 
> Hm.
> It looks like the "close" code for if_tap clears out the addresses of
> the interface with a pretty blunt-edged "bzero", rather than removing
> them in any clean fashion. As a result, ifconfig gets confused over
> the address families in the tags it sees on the addresses it
> enumerates off the tap interface, and collapses with a corefile.
> 
> if_tap's "close" seems to be trying to do part of what's done in
> if_detach, so I split out what I think are the relevant bits from
> there and used it in both places.
> 
> Any networking experts care to take a look at the patch? I suspect
> there's a whole mess of locking I'm not doing for a start, but I think
> it might be an improvement over the current situation.

i'm not an expert, but i took a brief look at it, and, it looks fine to 
me. does this patch fix the ifconfig(8) problem?

max