Excellent job on the firewire support!
Maxim Sobolev
sobomax at portaone.com
Fri Jul 23 07:53:05 PDT 2004
Doug Rabson wrote:
> On Wed, 2004-07-21 at 15:41, Andrew Gallatin wrote:
>
>>Doug Rabson writes:
>> > Actually thats the only downside of dcons. It doesn't cut in until the
>> > firewire controller attaches. It relies on the fact that the fwohci
>> > driver allows access to physical memory from any node on the bus
>> > (implemeted in hardware so you can examine the memory of a hung
>> > machine). The dconschat program uses this feature to access the dcons
>> > ring buffers in the target machine.
>>
>>Does remote access to physical memory require dcons to be loaded
>>on the target?
>
>
> No. The remote access to physical memory is a hardware-implemented
> feature of the firewire ohci hardware. Its enabled in fwohci_attach().
> In the long term, I would like to restrict this a bit but right now all
> you have to have is fwohci loaded on the target machine.
It would be nice to have some sysctl which to disable such access, since
it is BAD THING[tm] from the security POV.
-Maxim
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