[PATCH net-next 0/2 v5] netns: uevent filtering

From: Christian Brauner <christian.brauner@ubuntu.com>
To: ebiederm@xmission.com, davem@davemloft.net,
	netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: avagin@virtuozzo.com, ktkhai@virtuozzo.com, serge@hallyn.com,
	gregkh@linuxfoundation.org,
	Christian Brauner <christian.brauner@ubuntu.com>
Subject: [PATCH net-next 0/2 v5] netns: uevent filtering
Date: Sun, 29 Apr 2018 12:44:10 +0200	[thread overview]
Message-ID: <20180429104412.22445-1-christian.brauner@ubuntu.com> (raw)

Hey everyone,

This is the new approach to uevent filtering as discussed (see the
threads in [1], [2], and [3]). It only contains *non-functional
changes*.

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)

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 | 178 ++++++++++++++++++++++++++++++-------------
 1 file changed, 126 insertions(+), 52 deletions(-)

-- 
2.17.0