Re: [PATCH v6 0/1] ns: introduce binfmt_misc namespace

From: Laurent Vivier
Date: Sat Dec 29 2018 - 10:42:15 EST



Le 29/11/2018 Ã 14:05, Laurent Vivier a ÃcritÂ:
> Le 01/11/2018 Ã 15:16, Eric W. Biederman a ÃcritÂ:
>> Laurent Vivier <laurent@xxxxxxxxx> writes:
>>> On 01/11/2018 04:51, Jann Horn wrote:
>>>> On Thu, Nov 1, 2018 at 3:59 AM James Bottomley
>>>> <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
>>>>> On Tue, 2018-10-16 at 11:52 +0200, Laurent Vivier wrote:
>>>>>> Hi,
>>>>>> Any comment on this last version?
>>>>>> Any chance to be merged?
>>>>> I've got a use case for this: I went to one of the Graphene talks in
>>>>> Edinburgh and it struck me that we seem to keep reinventing the type of
>>>>> sandboxing that qemu-user already does. However if you want to do an
>>>>> x86 on x86 sandbox, you can't currently use the binfmt_misc mechanism
>>>>> because that has you running *every* binary on the system emulated.
>>>>> Doing it per user namespace fixes this problem and allows us to at
>>>>> least cut down on all the pointless duplication.
>>>> Waaaaaait. What? qemu-user does not do "sandboxing". qemu-user makes
>>>> your code slower and *LESS* secure. As far as I know, qemu-user is
>>>> only intended for purposes like development and testing.
>>> I think the idea here is not to run qemu, but to use an interpreter
>>> (something like gVisor) into a container to control the binaries
>>> execution inside the container without using this interpreter on the
>>> host itself (container and host shares the same binfmt_misc
>>> magic/mask).
>> Please remind me of this patchset after the merge window is over, and if
>> there are no issues I will take it via my user namespace branch.
>> Last I looked I had a concern that some of the permission check issues
>> were being papered over by using override cred instead of fixing the
>> deaper code. Sometimes they are necessary but seeing work-arounds
>> instead of fixes for problems tends to be a maintenance issue, possibly
>> with security consequences. Best is if the everyone agrees on how all
>> of the interfaces work so their are no surprises.
> I don't know where we are in the merge window, but is there something I
> can do to have this merged?
> Thanks,
> Laurent