should looking at an interface with 'ifconfig' trigger a ?change ?

David Adam zanchey at
Sat Aug 9 06:07:56 UTC 2008

On Fri, 8 Aug 2008, Oliver Fromme wrote:
> Andrew Thompson wrote:
>  > ifconfig will cause the media status to be read from the hardware at
>  > which time the link change is generated as it is different to the stored
>  > value.
> Shouldn't that be considered a security flaw?  After all,
> you can perform "ifconfig $IF" inside a jail to list the
> interface configuration, but you're not allowed to make
> any changes.
> Given your description above, it means that it is possible
> to modify the interface configuration (cause a failover)
> from within a jail.  That's not good.  I think that needs
> to be fixed, or at the very least it needs to be properly
> documented.

I can't see how this is a security flaw. The link is already down; 
ifconfig is merely updating the OS' knowlege of the link status to be 
closer to reality.

David Adam
zanchey at

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