[coreboot] v2: is this a bug ? (in device_util.c)

[Eric W. Biederman]

Stefan Reinauer <stepan at coresystems.de> writes:

> JasonZhao at viatech.com.cn wrote:
>>
>> Hardwaremain()-> dev_configure();-> void
>> root_dev_read_resources(device_t root) ->
>>
>> void compact_resources(device_t dev)->
>>
>> memmove(resource, resource + 1, dev->resources - i); 
>>
>> The third parameter should be (dev->resources-I)* sizeof(*resource)
>>
> Dear Jason,
>
> thank you very much for your finding!
>
> It is indeed a bug and should be fixed.
>
> I am surprised we did not hit this before, as this potentially wipes out
> whole resource entries. (unless the number of resources is bigger than
> the size of a resource in bytes)
>
> But only if there are holes in the resource entries. Not sure why/how
> these occur. Eric, your word!

Looking at the code I'm fairly certain that we never or practically never
exercise it.  To create a hole it would require someone to call new_resource
and then never setup the resource.  compact_resources looks to be there just
in case that happens, rather than to handle an actual case that someone has
hit.

We have a small static pool of 24 resources on each device, and a struct
resource looks to be 64 bytes.

Eric