[OE-core] [PATCH v2] base-passwd: Add kvm group

[Mark Hatle]

Nothing special.. bbappend base-passwd and replace the SRC_URI with a custom
version of passwd.master and group.master.

--Mark

On 10/21/19 12:42 PM, Joshua Watt wrote:
> 
> On 10/21/19 12:23 PM, Mark Hatle wrote:
>>
>> On 10/21/19 12:03 PM, Joshua Watt wrote:
>>> On Sun, Feb 3, 2019 at 9:13 PM Jacob Kroon <jacob.kroon at gmail.com> wrote:
>>>> Although base-passwd in OE is somewhat outdated, upgrading
>>>> to a newer version is not going to solve eudev warnings about
>>>> missing groups during boot; input/shutdown/kvm are still not
>>>> listed in groups.master. The reason for this is that
>>>> Debian uses systemd, which will automatically create
>>>> missing groups(systemd-sysusers). In a sysvinit+eudev
>>>> configuration you instead get a warning printed to
>>>> the console:
>>> There is an unfortunate problem with this patch that is causing us
>>> build failures when using useradd-staticids. Part of this might be our
>>> fault for not realizing the repercussions in the way we chose static
>>> IDs, but it exposes some deeper issues with this approach to "patching
>>> in" new users and groups that we need to be careful about.
>>>
>>> In our case, the problem is that we added the netdev group to our
>>> static group file at ID 47. As such, we get a warning when the netdev
>>> group is created:
>>>   groupadd: GID '47' already exists.
>>>
>>> For our part, choosing to tightly pack the group IDs and fill in the
>>> missing holes with our own static IDs when those static IDs might be
>>> allocated by upstream in the future was probably a poor choice.
>>> However, the same reasons that make it a poor choice for us also apply
>>> to this patch. Upstream doesn't have this GID, and *could* (although
>>> unlikely will) add a different group at ID 47, which would conflict
>>> with this patch and cause a lot of havoc with anyone using
>>> useradd-staticids.
>>>
>>> Compounding this is the problem that the users and groups in
>>> base-passwd don't play nice in general with useradd-staticids. The
>>> users and groups provided by base-passwd are always assumed to exists
>>> with the fixed IDs assigned by the recipe, and there is no mechanism
>>> to override the assigned IDs with a static ID file as can be done with
>>> useradd.bbclass (also, adding support doesn't appear to be trivial).
>> This was part of the original design of the static ids.
>>
>> When using static IDs, you should be providing your own base passwd/group files
>> and optionally the static mapping files as well.
> 
> Ah, I don't think that providing a custom base passwd/group file was 
> clearly documented. That does make sense and will allow us to work 
> around the issue. Is there an example of how that is done somewhere?
> 
>>
>> This is the purpose of the USERADD_UID_TABLES, you can pass in the passwd/group
>> files as inputs to these...
>>
>>> In general, I don't think we should be "patching in" users and groups
>>> like this to base-passwd. If upstream doesn't have them, they need to
>>> be added through the normal useradd.bbclass mechanism so that users of
>>> useradd-staticids can choose what ID they get mapped to.
>>>
>>> Is it possible to revert this and add the kvm group via the useradd.bbclass?
>>>
>>>>    udevd[<pid>]: specified group 'kvm' unknown
>> As for this particular patch, why is adding a specific KVM group required?
>> Unless something is hardcoded in KVM to use group '47', a regular system type
>> useradd call should be done instead.  This would avoid the problem that Joshua
>> is experiencing.
>>
>> --Mark
>>
>>>> Signed-off-by: Jacob Kroon <jacob.kroon at gmail.com>
>>>> ---
>>>>
>>>> v2: Add reasoning in commit message trying to justify the added patch
>>>>
>>>>   .../base-passwd/base-passwd/kvm.patch         | 23 +++++++++++++++++++
>>>>   .../base-passwd/base-passwd_3.5.29.bb         |  3 ++-
>>>>   2 files changed, 25 insertions(+), 1 deletion(-)
>>>>   create mode 100644 meta/recipes-core/base-passwd/base-passwd/kvm.patch
>>>>
>>>> diff --git a/meta/recipes-core/base-passwd/base-passwd/kvm.patch b/meta/recipes-core/base-passwd/base-passwd/kvm.patch
>>>> new file mode 100644
>>>> index 0000000000..113d5151e7
>>>> --- /dev/null
>>>> +++ b/meta/recipes-core/base-passwd/base-passwd/kvm.patch
>>>> @@ -0,0 +1,23 @@
>>>> +From 6355278b9f744291864c373a32a8da8f84aaaf37 Mon Sep 17 00:00:00 2001
>>>> +From: Jacob Kroon <jacob.kroon at gmail.com>
>>>> +Date: Wed, 30 Jan 2019 04:53:48 +0000
>>>> +Subject: [PATCH] Add kvm group
>>>> +
>>>> +Upstream-Status: Pending
>>>> +Signed-off-by: Jacob Kroon <jacob.kroon at gmail.com>
>>>> +---
>>>> + group.master | 1 +
>>>> + 1 file changed, 1 insertion(+)
>>>> +
>>>> +diff --git a/group.master b/group.master
>>>> +index cea9d60..5b62284 100644
>>>> +--- a/group.master
>>>> ++++ b/group.master
>>>> +@@ -34,6 +34,7 @@ utmp:*:43:
>>>> + video:*:44:
>>>> + sasl:*:45:
>>>> + plugdev:*:46:
>>>> ++kvm:*:47:
>>>> + staff:*:50:
>>>> + games:*:60:
>>>> + shutdown:*:70:
>>>> diff --git a/meta/recipes-core/base-passwd/base-passwd_3.5.29.bb b/meta/recipes-core/base-passwd/base-passwd_3.5.29.bb
>>>> index c6be1c1d08..d1aab09181 100644
>>>> --- a/meta/recipes-core/base-passwd/base-passwd_3.5.29.bb
>>>> +++ b/meta/recipes-core/base-passwd/base-passwd_3.5.29.bb
>>>> @@ -12,7 +12,8 @@ SRC_URI = "https://launchpad.net/debian/+archive/primary/+files/${BPN}_${PV}.tar
>>>>              file://noshadow.patch \
>>>>              file://input.patch \
>>>>              file://disable-docs.patch \
>>>> -          "
>>>> +           file://kvm.patch \
>>>> +           "
>>>>
>>>>   SRC_URI[md5sum] = "6beccac48083fe8ae5048acd062e5421"
>>>>   SRC_URI[sha256sum] = "f0b66388b2c8e49c15692439d2bee63bcdd4bbbf7a782c7f64accc55986b6a36"
>>>> --
>>>> 2.20.1
>>>>
>>>> --
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