Subject: Re: [PATCH net-next 0/2] netns: uevent filtering

From: [email-masked] (Eric W. Biederman)
Date: Fri, 27 Apr 2018 11:27:02 -0500

Christian Brauner <[email-masked]> writes:

> Hey everyone,
>
> This is the new approach to uevent filtering as discussed (see the
> threads in [1], [2], and [3]).
>
> This series deals with with fixing up uevent filtering logic:
> - uevent filtering logic is simplified
> - locking time on uevent_sock_list is minimized
> - tagged and untagged kobjects are handled in separate codepaths
> - permissions for userspace are fixed for network device uevents in
>   network namespaces owned by non-initial user namespaces
>   Udev is now able to see those events correctly which it wasn't before.
>   For example, moving a physical device into a network namespace not
>   owned by the initial user namespaces before gave:
>
>   root@xen1:~# udevadm --debug monitor -k
>   calling: monitor
>   monitor will print the received events for:
>   KERNEL - the kernel uevent
>
>   sender uid=65534, message ignored
>   sender uid=65534, message ignored
>   sender uid=65534, message ignored
>   sender uid=65534, message ignored
>   sender uid=65534, message ignored
>
>   and now after the discussion and solution in [3] correctly gives:
>
>   root@xen1:~# udevadm --debug monitor -k
>   calling: monitor
>   monitor will print the received events for:
>   KERNEL - the kernel uevent
>
>   KERNEL[625.301042] add      /devices/pci0000:00/0000:00:02.0/0000:01:00.1/net/enp1s0f1 (net)
>   KERNEL[625.301109] move     /devices/pci0000:00/0000:00:02.0/0000:01:00.1/net/enp1s0f1 (net)
>   KERNEL[625.301138] move     /devices/pci0000:00/0000:00:02.0/0000:01:00.1/net/eth1 (net)
>   KERNEL[655.333272] remove /devices/pci0000:00/0000:00:02.0/0000:01:00.1/net/eth1 (net)

Acked-by: "Eric W. Biederman" <[email-masked]>

Overall this change looks good and I would nave not problems
if it was merged as it.  I have one or two nits.  But they are not
particularly important.

Eric

> Thanks!
> Christian
>
> [1]: https://lkml.org/lkml/2018/4/4/739
> [2]: https://lkml.org/lkml/2018/4/26/767
> [3]: https://lkml.org/lkml/2018/4/26/738
>
> Christian Brauner (2):
>   uevent: add alloc_uevent_skb() helper
>   netns: restrict uevents
>
>  lib/kobject_uevent.c | 175 ++++++++++++++++++++++++++++++-------------
>  1 file changed, 123 insertions(+), 52 deletions(-)