Re: image-postproc-extension.bbclass modifying /etc/os-release

[Silvano Cirujano Cuesta <silvano.cirujano-cuesta@siemens.com>]

On 19/01/2021 09:43, Henning Schild wrote:
> Hi,
>
> i wonder if there is any command we can run for QA. One that makes sure
> that all files in the rootfs are owned by a package and are not
> modified. That should take /etc /var /tmp and other such locations into
> account, but should clearly detect the problematic change in /usr/lib
> that slipped in via that unexpected symlink.

It's not that easy. Files generated during package post-processing are not owned by any package.

>
> Does anyone know such a command?

Yes, "dpkg -S" is what you're looking for. For example, "dpkg -S /etc/os-release" returns "base-files: /etc/os-release". Or the other way around, "dpkg -L base-files" gives you all the files managed by "base-files". With "dpkg -S" you can use globbing, but it reports also directories. In the end it's easier something like "find <rootfs> -type f -exec dpkg -S {} \;" if you want to scan the whole tree.

 Silvano

>
> Henning
>
> Am Fri, 15 Jan 2021 15:26:14 +0100
> schrieb "[ext] Silvano Cirujano Cuesta"
> <silvano.cirujano-cuesta@siemens.com>:
>
>> Hi,
>>
>> I've noticed that '/etc/os-release' is being changed on the image in
>> meta/classes/image-postproc-extension.bbclass [1].  What BTW ends up
>> changing '/usr/lib/os-release', since it's only a symlink. But both
>> '/etc/os-release' and '/usr/lib/os-release' are owned by
>> 'base-files'...
>>
>> An upgrade of 'base-files' would be replacing (silently, since is not
>> marked as a configuration file) '/usr/lib/os-release' with the
>> version of the upstream 'base-files' package and possibly breaking
>> any tools in the system relying on certain values in that file.
>>
>> Is there a reason that I'm missing for doing so instead of the
>> Debian-way (file diversion with dpkg-divert)? Or any hack that I've
>> overseen that avoids the mentioned breakage?
>>
>> Hasta la vista,
>>
>>   Silvano
>>
>> [1]
>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Filbers%2Fisar%2Fblob%2Fa0d6de4ac7dfb926b38cfcd44f2bc8852f2e43e3%2Fmeta%2Fclasses%2Fimage-postproc-extension.bbclass%23L20&amp;data=04%7C01%7Csilvano.cirujano-cuesta%40siemens.com%7C2e50ef427a76472a2c3308d8bc565c87%7C38ae3bcd95794fd4addab42e1495d55a%7C1%7C0%7C637466426394815917%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=DP6mMX8xBVzZ6v0PupvNXCJb8Amrf%2Fwh91dT9XSL6I8%3D&amp;reserved=0
>>
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