[gentoo-dev] CWD-relative ROOT support in portage: misfeature?

[gentoo-dev] CWD-relative ROOT support in portage: misfeature?

[Gregory M. Turner]

It has come to my attention that gentoo supports "relative" ROOT, which 
is to say that, by design, portage will act as though (in bash terms):

   ROOT

equals

   "${PWD}/${ROOT}"

when (again in bash terms):

   [[ $ROOT != /* ]]

at the moment execution crosses the boundary between a non-portage 
program and a portage program.  For example, I ran the following from a 
bash-prompt with PWD=/tmp in a portage-2.2 ~amd64 environment:

   greg@fedora64vmw /tmp $ mkdir foo
   greg@fedora64vmw /tmp $ ROOT=foo portageq envvar ROOT
   /tmp/foo/

Question: do we really want this behavior?

I have reason to believe that almost nobody uses this feature (namely, 
gcc-config and binutils-config are both broken under it for ages and 
nobody filed a bug or fixed it: see bugzilla #431104).

Does /anybody/ use this feature?  If not, I'd suggest that the portage 
team might ask itself whether the benefits of continuing to maintain it 
are greater than the hassle and potential for error it facilitates.

Just my 2c,

-gmt

Re: [gentoo-dev] CWD-relative ROOT support in portage: misfeature?

[Ian Stakenvicius]

On 2012-08-17, at 11:00 PM, "Gregory M. Turner" <gmt@malth.us> wrote:

> It has come to my attention that gentoo supports "relative" ROOT, which is to say that, by design, portage will act as though (in bash terms):
> 
>  ROOT
> 
> equals
> 
>  "${PWD}/${ROOT}"
> 
> when (again in bash terms):
> 
>  [[ $ROOT != /* ]]
> 
> at the moment execution crosses the boundary between a non-portage program and a portage program.  For example, I ran the following from a bash-prompt with PWD=/tmp in a portage-2.2 ~amd64 environment:
> 
>  greg@fedora64vmw /tmp $ mkdir foo
>  greg@fedora64vmw /tmp $ ROOT=foo portageq envvar ROOT
>  /tmp/foo/
> 
> Question: do we really want this behavior?
> 
> I have reason to believe that almost nobody uses this feature (namely, gcc-config and binutils-config are both broken under it for ages and nobody filed a bug or fixed it: see bugzilla #431104).
> 
> Does /anybody/ use this feature?  If not, I'd suggest that the portage team might ask itself whether the benefits of continuing to maintain it are greater than the hassle and potential for error it facilitates.
> 
> Just my 2c,
> 
> -gmt


Sorry for the HTML response... am on the road.

I don't use the feature but I would fully expect said behavior. ie, going with the example above I would expect that I'd need   the / in front for the path to not be relative.






> 

Re: [gentoo-dev] CWD-relative ROOT support in portage: misfeature?

[Gregory M. Turner]

On 8/18/2012 5:50 PM, Ian Stakenvicius wrote:
>
> On 2012-08-17, at 11:00 PM, "Gregory M. Turner" <gmt@malth.us> wrote:
>
>>   greg@fedora64vmw /tmp $ mkdir foo
>>   greg@fedora64vmw /tmp $ ROOT=foo portageq envvar ROOT
>>   /tmp/foo/
>>
>> Does /anybody/ use this feature?
>
> Sorry for the HTML response... am on the road.
>
> I don't use the feature but I would fully expect said behavior. ie, going with the example above I would expect that I'd need   the / in front for the path to not be relative.

A user and maintainer of this (vapier) has emerged.  I pooh-poohed the 
relative-ROOT idea when I discovered it a few days ago, but I've 
flip-flopped.  I was concerned it would be exploitable by Bad 
People(tm), but I think it's no more exploitable than absolute-only 
ROOT, so long as its implemented correctly.

So far, nobody's turned up to advocate against the status quo (except 
me, but I'm fine with it now), so I think the matter can be considered 
resolved.

-gmt