Re: [PATCH 1/7] dpkg-raw: Respect file permissions defined by recipe

[Jan Kiszka <jan.kiszka@siemens.com>]

On 07.01.19 17:28, Henning Schild wrote:
> Am Mon, 7 Jan 2019 15:26:16 +0100
> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
> 
>> On 07.01.19 15:20, Jan Kiszka wrote:
>>> On 07.01.19 15:19, Henning Schild wrote:
>>>> Am Mon, 7 Jan 2019 14:28:47 +0100
>>>> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
>>>>   
>>>>> On 07.01.19 14:20, Henning Schild wrote:
>>>>>> Am Wed, 2 Jan 2019 12:34:11 +0100
>>>>>> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
>>>>>>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>>>>>>
>>>>>>> dh_fixperms overwrites the permissions do_install defined
>>>>>>> carefully. Skip this step to avoid that.
>>>>>>>
>>>>>>> Fixes: f301ccb2b5b1 ("meta/dpkg-raw: build raw packages like all
>>>>>>> others") CC: Henning Schild <henning.schild@siemens.com>
>>>>>>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>>>>>>> ---
>>>>>>>     meta/classes/dpkg-raw.bbclass | 4 +++-
>>>>>>>     1 file changed, 3 insertions(+), 1 deletion(-)
>>>>>>>
>>>>>>> diff --git a/meta/classes/dpkg-raw.bbclass
>>>>>>> b/meta/classes/dpkg-raw.bbclass index 8d11433..10fb1b9 100644
>>>>>>> --- a/meta/classes/dpkg-raw.bbclass
>>>>>>> +++ b/meta/classes/dpkg-raw.bbclass
>>>>>>> @@ -56,9 +56,11 @@ EOF
>>>>>>>     deb_create_rules() {
>>>>>>>         cat << EOF > ${S}/debian/rules
>>>>>>>     #!/usr/bin/make -f
>>>>>>> +
>>>>>>> +override_dh_fixperms:
>>>>>>> +
>>>>>>>     %:
>>>>>>>         dh \$@
>>>>>>> -
>>>>>>
>>>>>> I think it is not a good idea to do that in general. While you
>>>>>> might have found an example where dh_fixperms caused problems,
>>>>>> there are probably many where it helps. Say people use "cp" to
>>>>>> fill ${D} or "echo" to fill ${D}/bin/
>>>>>
>>>>> I'm open for better suggestions.
>>>>
>>>> The suggestion is to do that in the one recipe that you need it
>>>> for, and not touch the general case.
>>>
>>> ...except for causing that regression: Keep in mind that we used to
>>> respect permissions defined by the user before the switch to
>>> packaging via Debian!
> 
> True, but there is a changelog section that even tells users how to
> disable certain dhs for their recipes.
> 
>> To make my issue more concrete: Consider you want to package secrets
>> this way. Then it would be rather ugly to even temporary have them
>> group or even work readable during packaging and installation - in
>> case you suggestion should be to adjust the permissions in a postinst.
> 
> Having secrets in your repo and build process would be ugly as well,
> many spots where they could leak. So i do not think that is a good
> example.
> And i am not talking about a postinst, but a rules file that does
> exactly what yours does. See what example-raw does for dh_usrlocal, if
> you bring your rules you do not get the defaults.
> Looking at the man-page i see a lot of "removes permission", where
> documentation seems to be the only exception. Again secret does not
> seem to be a good example. (except you place it in usr/share/doc ;) )
> 
> What exactly is your motivation for the change?

Allow to ship files that are not world-readable by defaults. That's a pretty 
common pattern, e.g. to add pre-generated keys, certificates, wifi passwords etc.

So I don't think it is a good idea that dpkg-raw now breaks this use case, 
sometimes silently(!), and forces users to overload their rules files. I'm not 
even sure that it makes sense for Debian to add these permissions to during the 
fixperms phase, but I didn't dig into that details.

Jan

-- 
Siemens AG, Corporate Technology, CT RDA IOT SES-DE
Corporate Competence Center Embedded Linux