attempts to rename vlans / vlans have addr_assign_type of 0 on kernel 4.4

[Scott Moser]

[Impact]

 * When vlan interfaces are created, their mac address is copied from the underlying interface, but it is not marked by kernel as stolen.

 * When underlying interface MAC address is changed, it does not propagate to the vlan interfaces.

[Test Case]

 * Create vlan interface, check the addr_assign_type sysfs attribute, it should be 2, not 0.

 * Update the base interface mac address, the mac address of the vlan interface should change too.

 * cloud-init test case

wget https://git.launchpad.net/~smoser/cloud-init/+git/sru-info/plain/bin/get-proposed-cloudimg;
chmod 755 get-proposed-cloudimg;

for release in xenial yakkety zesty; do
  ./get-proposed-cloudimg $release;
  MODE=vlan ./btest-launch.sh $release-server-cloudimg-amd64-proposed.img <LP_ID>;
  # ubuntu/passw0rd
  python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'; # results in no runtime error and doesn't report vlan interface name
done

[Regression Potential]

 * Userspace may rely on non-propagating MAC addresses, and the fact that vlan mac address type is wrongly stated as non-stolen; however this behaviour will be consistent with 4.7+ kernels.

[Other Info]

 * Please cherrypick 308453aa9156a3b8ee382c0949befb507a32b0c1 into v4.4 kernels

commit 308453aa9156a3b8ee382c0949befb507a32b0c1
Author: Mike Manning <email address hidden>
Date: Fri May 27 17:45:07 2016 +0100

    vlan: Propagate MAC address to VLANs

    The MAC address of the physical interface is only copied to the VLAN
    when it is first created, resulting in an inconsistency after MAC
    address changes of only newly created VLANs having an up-to-date MAC.

    The VLANs should continue inheriting the MAC address of the physical
    interface until the VLAN MAC address is explicitly set to any value.
    This allows IPv6 EUI64 addresses for the VLAN to reflect any changes
    to the MAC of the physical interface and thus for DAD to behave as
    expected.

    Signed-off-by: Mike Manning <email address hidden>
    Signed-off-by: David S. Miller <email address hidden>

 * Original bug report

When attempting to verify sru for bug 1669860, I found that vlans
are not properly filtered out by 'get_interfaces_by_mac'. That means
that the bug is still present with vlans.

The reason for this is that /sys/class/net/<vlan_name>/addr_assign_type
shows '0' for a vlan on 4.4, but (correctly) shows '2' on 4.8.
See https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-class-net
for doc on addr_assign_type.

Related bugs:
 * bug 1669860: cloud-init attempts to rename bonds

[Scott Moser (smoser)]

It seems that this only reproduces on kernel 4.8, but does on 4.4.
The change put in to ignore certain nics was done based on 'addr_assign_type'
(/sys/class/net/<name>/addr_assign_type).
On 4.4 for a vlan, that shows as '0', (permanent address).
On 4.8, it (correctly) shows as '2' (stolen from another device)

To recreate this you can run the attached script.

$ MODE=vlan ./btest-launch.sh yakkety-server-cloudimg-amd64-proposed.img
...log in as ubuntu:password ...

Note, I can see this fail on xenial with 0.7.9-90-g61eb03fe-0ubuntu1~16.04.1
but cannot see it fail in yakkety I

## xenial
$ uname -r
4.4.0-72-generic
$ python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/cloudinit/net/__init__.py", line 403, in get_interfaces_by_mac
    (name, ret[mac], mac))
RuntimeError: duplicate mac found! both 'interface1.108' and 'interface1' have mac '52:54:00:12:34:02'

$ grep -r . /sys/class/net/*/ 2>/dev/null | grep addr_assign_type
/sys/class/net/interface0/addr_assign_type:0
/sys/class/net/interface1/addr_assign_type:0
/sys/class/net/interface1.108/addr_assign_type:0
/sys/class/net/lo/addr_assign_type:0

### yakkety
$ python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'
{'00:00:00:00:00:00': 'lo', '52:54:00:12:34:00': 'interface0', '52:54:00:12:34:02': 'interface1'}

$ uname -r
4.8.0-46-generic

$ grep -r . /sys/class/net/*/ 2>/dev/null | grep addr_assign_type
/sys/class/net/interface0/addr_assign_type:0
/sys/class/net/interface1/addr_assign_type:0
/sys/class/net/interface1.108/addr_assign_type:2
/sys/class/net/lo/addr_assign_type:0

[Dimitri John Ledkov (xnox)]

I wonder if this really should go to linux-stable too.

[Dimitri John Ledkov (xnox)]

Adding a cloud-init workaround patch for kernels before 4.7 too.

[Dimitri John Ledkov (xnox)]

The cloud init patch needs work...

>>> interface_has_own_mac('bonding_masters')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python3/dist-packages/cloudinit/net/__init__.py", line 226, in interface_has_own_mac
    uevent = read_sys_net_safe(ifname, 'uevent').splitlines()
AttributeError: 'bool' object has no attribute 'splitlines'

[Dimitri John Ledkov (xnox)]

Hm, I don't think you will win much here. vlans made from a bond have addr_assign_type 3.

root@xnox-iad-16:/sys/class/net# uname -r
4.8.0-46-generic

root@xnox-iad-16:/sys/class/net# grep -e 0 -e 1 -e 2 -e 3 */addr_assign_type
bond0.101/addr_assign_type:3
bond0.401/addr_assign_type:3
bond0/addr_assign_type:2
ens9f0/addr_assign_type:3
ens9f1/addr_assign_type:3
lo/addr_assign_type:0

[Kleber Sacilotto de Souza (kleber-souza)]

I am building a xenial test kernel with the patch attached on comment #2. I will post the link here once it's ready.

[Kleber Sacilotto de Souza (kleber-souza)]

Hi,

Could you please try the following patched kernel and check if it fixes the issue?

PPA: https://launchpad.net/~kleber-souza/+archive/ubuntu/ppa
Package: linux=4.4.0-74.95+lp1682871v1

Thank you in advance.

[Launchpad Janitor (janitor)]

This bug was fixed in the package cloud-init - 0.7.9-113-g513e99e0-0ubuntu1

---------------
cloud-init (0.7.9-113-g513e99e0-0ubuntu1) artful; urgency=medium

  * New upstream snapshot.
    - nova-lxd: read product_name from environment, not platform.
      (LP: #1685810)
    - Fix yum repo config where keys contain array values
      [Dylan Perry] (LP: #1592150)
    - template: Update debian backports template [Joshua Powers] (LP: #1627293)
    - rsyslog: replace ~ with stop [Joshua Powers] (LP: #1367899)
    - Doc: add additional RTD examples [Joshua Powers] (LP: #1459604)
    - Fix growpart for some cases when booted with root=PARTUUID.
      (LP: #1684869)
    - pylint: update output style to parseable [Joshua Powers]
    - pylint: fix all logging warnings [Joshua Powers]
    - CloudStack: Add NetworkManager to list of supported DHCP lease dirs.
      [Syed Mushtaq Ahmed]
    - net: kernel lies about vlans not stealing mac addresses, when they do
      [Dimitri John Ledkov] (LP: #1682871)
    - ds-identify: Check correct path for "latest" config drive
      [Daniel Watkins] (LP: #1673637)
    - doc: Fix example for resolve.conf configuration.
      [Jon Grimm] (LP: #1531582)
    - Fix examples that reference upstream chef repository.
      [Jon Grimm] (LP: #1678145)
    - doc: correct grammar and improve clarity in merging documentation.
      [David Tagatac]
    - doc: Add missing doc link to snap-config module. [Ryan Harper]
    - snap: allows for creating cloud-init snap [Joshua Powers]
    - DigitalOcean: assign IPv4ll address to lowest indexed interface.
      [Ben Howard]
    - DigitalOcean: configure all NICs presented in meta-data. [Ben Howard]
    - Remove (and/or fix) URL shortener references [Jon Grimm] (LP: #1669727)
    - HACKING.rst: more info on filling out contributors agreement.
      [Scott Moser]
    - util: teach write_file about copy_mode option
      [Lars Kellogg-Stedman] (LP: #1644064)
    - DigitalOcean: bind resolvers to loopback interface. [Ben Howard]
    - tests: fix AltCloud tests to not rely on blkid (LP: #1636531)

 -- Scott Moser <email address hidden> Tue, 25 Apr 2017 16:34:08 -0400

[Kleber Sacilotto de Souza (kleber-souza)]

Hi Scott,

Did you have a chance to test the patched Xenial kernel to check whether is fixes the issue on the kernel side?

Thank you.

[Steve Langasek (vorlon)]

Hello Scott, or anyone else affected,

Accepted cloud-init into xenial-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/cloud-init/0.7.9-113-g513e99e0-0ubuntu1~16.04.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Chad Smith (chad.smith)]

Verified cloud-init xenial
$ ./get-proposed-cloudimg xenial
--2017-05-11 14:11:13-- http://cloud-images.ubuntu.com/daily/server/xenial/current/xenial-server-cloudimg-amd64-disk1.img
...
xenial-server-cloud 100%[===================>] 273.75M 9.87MB/s in 2m 29s

2017-05-11 14:13:42 (1.83 MB/s) - ‘xenial-server-cloudimg-amd64.img.tmp’ saved [287047680/287047680]
$ MODE=vlan ./btest.sh xenial-server-cloudimg-amd64-proposed.img chad.smith
# login w/ ubuntu/passw0rd

ubuntu@ubuntu:~$ python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'
{'00:00:00:00:00:00': 'lo', '52:54:00:12:34:00': 'interface0', '52:54:00:12:34:02': 'interface1'}
ubuntu@ubuntu:~$

ubuntu@ubuntu:~$ dpkg -l | grep cloud-init
ii cloud-init 0.7.9-113-g513e99e0-0ubuntu1~16.04.1 all Init scripts for cloud instances

[Steve Langasek (vorlon)]

Hello Scott, or anyone else affected,

Accepted cloud-init into yakkety-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/cloud-init/0.7.9-113-g513e99e0-0ubuntu1~16.10.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Steve Langasek (vorlon)]

Hello Scott, or anyone else affected,

Accepted cloud-init into zesty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/cloud-init/0.7.9-113-g513e99e0-0ubuntu1~17.04.1 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation on how to enable and use -proposed.Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Kleber Sacilotto de Souza (kleber-souza)]

Thank you for confirming the fix. The patch was sent to the Canonical Kernel Team mailing list for review of inclusion on Xenial kernel SRU.

[Chad Smith (chad.smith)]

Verified yakkety and zesty

for release in yakkety zesty; do ./get-proposed-cloudimg $release; done
--2017-05-12 13:04:0
MODE=vlan ./btest.sh yakkety-server-cloudimg-amd64-proposed.img chad.smith
...
# login
ubuntu@ubuntu:~$ python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'
{'00:00:00:00:00:00': 'lo', '52:54:00:12:34:00': 'interface0', '52:54:00:12:34:02': 'interface1'}
ubuntu@ubuntu:~$ dpkg -l cloud-init
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-============-============-=================================
ii cloud-init 0.7.9-113-g5 all Init scripts for cloud instances
ubuntu@ubuntu:~$ grep VERSION= /etc/os-release
VERSION="16.10 (Yakkety Yak)"

ubuntu@ubuntu:~$ python3 -c 'from cloudinit.net import get_interfaces_by_mac; print(get_interfaces_by_mac())'
{'52:54:00:12:34:00': 'interface0', '52:54:00:12:34:02': 'interface1', '00:00:00:00:00:00': 'lo'}
ubuntu@ubuntu:~$ dpkg -l cloud-init
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-============-============-=================================
ii cloud-init 0.7.9-113-g5 all Init scripts for cloud instances

ubuntu@ubuntu:~$ grep VERSION= /etc/os-release
VERSION="17.04 (Zesty Zapus)"
ubuntu@ubuntu:~$

[Launchpad Janitor (janitor)]

This bug was fixed in the package cloud-init - 0.7.9-113-g513e99e0-0ubuntu1~16.04.1

---------------
cloud-init (0.7.9-113-g513e99e0-0ubuntu1~16.04.1) xenial-proposed; urgency=medium

  * debian/update-grub-legacy-ec2: fix early exit failure no /etc/fstab
    file. (LP: #1682160)
  * New upstream snapshot.
    - nova-lxd: read product_name from environment, not platform.
      (LP: #1685810)
    - Fix yum repo config where keys contain array values [Dylan Perry]
    - template: Update debian backports template [Joshua Powers]
    - rsyslog: replace ~ with stop [Joshua Powers] (LP: #1367899)
    - Doc: add additional RTD examples [Joshua Powers]
    - Fix growpart for some cases when booted with root=PARTUUID.
      (LP: #1684869)
    - pylint: update output style to parseable [Joshua Powers]
    - pylint: fix all logging warnings [Joshua Powers]
    - CloudStack: Add NetworkManager to list of supported DHCP lease dirs.
      [Syed Mushtaq Ahmed]
    - net: kernel lies about vlans not stealing mac addresses, when they do
      [Dimitri John Ledkov] (LP: #1682871)
    - ds-identify: Check correct path for "latest" config drive
      [Daniel Watkins] (LP: #1673637)
    - doc: Fix example for resolv.conf configuration. [Jon Grimm]
    - Fix examples that reference upstream chef repository. [Jon Grimm]
    - doc: correct grammar and improve clarity in merging documentation.
      [David Tagatac]
    - doc: Add missing doc link to snap-config module. [Ryan Harper]
    - snap: allows for creating cloud-init snap [Joshua Powers]
    - DigitalOcean: assign IPv4ll address to lowest indexed interface.
      [Ben Howard] (LP: #1676908)
    - DigitalOcean: configure all NICs presented in meta-data.
      [Ben Howard] (LP: #1676908)
    - Remove (and/or fix) URL shortener references [Jon Grimm]
    - HACKING.rst: more info on filling out contributors agreement.
    - util: teach write_file about copy_mode option
      [Lars Kellogg-Stedman] (LP: #1644064)
    - DigitalOcean: bind resolvers to loopback interface.
      [Ben Howard] (LP: #1676908)
    - tests: fix AltCloud tests to not rely on blkid (LP: #1636531)

 -- Scott Moser <email address hidden> Thu, 27 Apr 2017 12:51:04 -0400

[Chris Halse Rogers (raof)]

The verification of the Stable Release Update for cloud-init has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.

[Launchpad Janitor (janitor)]

This bug was fixed in the package cloud-init - 0.7.9-113-g513e99e0-0ubuntu1~16.10.1

---------------
cloud-init (0.7.9-113-g513e99e0-0ubuntu1~16.10.1) yakkety; urgency=medium

  * debian/update-grub-legacy-ec2: fix early exit failure no /etc/fstab
    file. (LP: #1682160)
  * New upstream snapshot.
    - nova-lxd: read product_name from environment, not platform.
      (LP: #1685810)
    - Fix yum repo config where keys contain array values [Dylan Perry]
    - template: Update debian backports template [Joshua Powers]
    - rsyslog: replace ~ with stop [Joshua Powers] (LP: #1367899)
    - Doc: add additional RTD examples [Joshua Powers]
    - Fix growpart for some cases when booted with root=PARTUUID.
      (LP: #1684869)
    - pylint: update output style to parseable [Joshua Powers]
    - pylint: fix all logging warnings [Joshua Powers]
    - CloudStack: Add NetworkManager to list of supported DHCP lease dirs.
      [Syed Mushtaq Ahmed]
    - net: kernel lies about vlans not stealing mac addresses, when they do
      [Dimitri John Ledkov] (LP: #1682871)
    - ds-identify: Check correct path for "latest" config drive
      [Daniel Watkins] (LP: #1673637)
    - doc: Fix example for resolv.conf configuration. [Jon Grimm]
    - Fix examples that reference upstream chef repository. [Jon Grimm]
    - doc: correct grammar and improve clarity in merging documentation.
      [David Tagatac]
    - doc: Add missing doc link to snap-config module. [Ryan Harper]
    - snap: allows for creating cloud-init snap [Joshua Powers]
    - DigitalOcean: assign IPv4ll address to lowest indexed interface.
      [Ben Howard] (LP: #1676908)
    - DigitalOcean: configure all NICs presented in meta-data.
      [Ben Howard] (LP: #1676908)
    - Remove (and/or fix) URL shortener references [Jon Grimm]
    - HACKING.rst: more info on filling out contributors agreement.
    - util: teach write_file about copy_mode option
      [Lars Kellogg-Stedman] (LP: #1644064)
    - DigitalOcean: bind resolvers to loopback interface.
      [Ben Howard] (LP: #1676908)
    - tests: fix AltCloud tests to not rely on blkid (LP: #1636531)

 -- Scott Moser <email address hidden> Thu, 27 Apr 2017 13:38:40 -0400

[Launchpad Janitor (janitor)]

This bug was fixed in the package cloud-init - 0.7.9-113-g513e99e0-0ubuntu1~17.04.1

---------------
cloud-init (0.7.9-113-g513e99e0-0ubuntu1~17.04.1) zesty; urgency=medium

  * debian/update-grub-legacy-ec2: fix early exit failure no /etc/fstab
    file. (LP: #1682160)
  * New upstream snapshot.
    - nova-lxd: read product_name from environment, not platform.
      (LP: #1685810)
    - Fix yum repo config where keys contain array values [Dylan Perry]
    - template: Update debian backports template [Joshua Powers]
    - rsyslog: replace ~ with stop [Joshua Powers] (LP: #1367899)
    - Doc: add additional RTD examples [Joshua Powers]
    - Fix growpart for some cases when booted with root=PARTUUID.
      (LP: #1684869)
    - pylint: update output style to parseable [Joshua Powers]
    - pylint: fix all logging warnings [Joshua Powers]
    - CloudStack: Add NetworkManager to list of supported DHCP lease dirs.
      [Syed Mushtaq Ahmed]
    - net: kernel lies about vlans not stealing mac addresses, when they do
      [Dimitri John Ledkov] (LP: #1682871)
    - ds-identify: Check correct path for "latest" config drive
      [Daniel Watkins] (LP: #1673637)
    - doc: Fix example for resolv.conf configuration. [Jon Grimm]
    - Fix examples that reference upstream chef repository. [Jon Grimm]
    - doc: correct grammar and improve clarity in merging documentation.
      [David Tagatac]
    - doc: Add missing doc link to snap-config module. [Ryan Harper]
    - snap: allows for creating cloud-init snap [Joshua Powers]
    - DigitalOcean: assign IPv4ll address to lowest indexed interface.
      [Ben Howard] (LP: #1676908)
    - DigitalOcean: configure all NICs presented in meta-data.
      [Ben Howard] (LP: #1676908)
    - Remove (and/or fix) URL shortener references [Jon Grimm]
    - HACKING.rst: more info on filling out contributors agreement.
    - util: teach write_file about copy_mode option
      [Lars Kellogg-Stedman] (LP: #1644064)
    - DigitalOcean: bind resolvers to loopback interface.
      [Ben Howard] (LP: #1676908)
    - tests: fix AltCloud tests to not rely on blkid (LP: #1636531)

 -- Scott Moser <email address hidden> Thu, 27 Apr 2017 15:09:31 -0400

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 4.4.0-83.106

---------------
linux (4.4.0-83.106) xenial; urgency=low

  * linux: 4.4.0-83.106 -proposed tracker (LP: #1700541)

  * CVE-2017-1000364
    - Revert "UBUNTU: SAUCE: mm: Only expand stack if guard area is hit"
    - Revert "mm: do not collapse stack gap into THP"
    - Revert "mm: enlarge stack guard gap"
    - mm: vma_adjust: remove superfluous confusing update in remove_next == 1 case
    - mm: larger stack guard gap, between vmas
    - mm: fix new crash in unmapped_area_topdown()
    - Allow stack to grow up to address space limit

linux (4.4.0-82.105) xenial; urgency=low

  * linux: 4.4.0-82.105 -proposed tracker (LP: #1699064)

  * CVE-2017-1000364
    - SAUCE: mm: Only expand stack if guard area is hit

  * linux-aws/linux-gke incorrectly producing and using linux-*-tools-
    common/linux-*-cloud-tools-common (LP: #1688579)
    - [Config] make linux-tools-common and linux-cloud-tools-common protection
      consistent

  * CVE-2017-9242
    - ipv6: fix out of bound writes in __ip6_append_data()

  * CVE-2017-9075
    - sctp: do not inherit ipv6_{mc|ac|fl}_list from parent

  * CVE-2017-9074
    - ipv6: Prevent overrun when parsing v6 header options

  * CVE-2017-9076
    - ipv6/dccp: do not inherit ipv6_mc_list from parent

  * CVE-2017-9077
    - ipv6/dccp: do not inherit ipv6_mc_list from parent

  * CVE-2017-8890
    - dccp/tcp: do not inherit mc_list from parent

  * Module signing exclusion for staging drivers does not work properly
    (LP: #1690908)
    - SAUCE: Fix module signing exclusion in package builds

  * extend-diff-ignore should use exact matches (LP: #1693504)
    - [Packaging] exact extend-diff-ignore matches

  * Dell XPS 9360 wifi 5G performance is poor (LP: #1692836)
    - SAUCE: ath10k: fix the wifi speed issue for kill 1535

  * Upgrade Redpine WLAN/BT driver to ver. 1.2.RC12 (LP: #1694607)
    - SAUCE: Redpine: Upgrade to ver. 1.2.RC12

  * [DP MST] No audio output through HDMI/DP/mDP ports in Dell WD15 and TB15
    docking stations (LP: #1694665)
    - drm/i915: Store port enum in intel_encoder
    - drm/i915: Eliminate redundant local variable definition
    - drm/i915: Switch to using port stored in intel_encoder
    - drm/i915: Move audio_connector to intel_encoder
    - drm/i915/dp: DP audio API changes for MST
    - drm/i915: abstract ddi being audio enabled
    - drm/i915/audio: extend get_saved_enc() to support more scenarios
    - drm/i915: enable dp mst audio

  * Xenial update to 4.4.70 stable release (LP: #1694621)
    - usb: misc: legousbtower: Fix buffers on stack
    - usb: misc: legousbtower: Fix memory leak
    - USB: ene_usb6250: fix DMA to the stack
    - watchdog: pcwd_usb: fix NULL-deref at probe
    - char: lp: fix possible integer overflow in lp_setup()
    - USB: core: replace %p with %pK
    - ARM: tegra: paz00: Mark panel regulator as enabled on boot
    - tpm_crb: check for bad response size
    - infiniband: call ipv6 route lookup via the stub interface
    - dm btree: fix for dm_btree_find_lowest_key()
    - dm raid: select the Kconfig option CONFIG_MD_RAID0
    - dm bufio: avoid a possible ABBA deadlock
    - dm bufio: check ...

[Scott Moser (smoser)]

This bug is believed to be fixed in cloud-init in 17.1. If this is still a problem for you, please make a comment and set the state back to New

Thank you.

[James Falcon (falcojr)]

Tracked in Github Issues as https://github.com/canonical/cloud-init/issues/2858