2018-10-08 19:04:29 |
Mauricio Faria de Oliveira |
bug |
|
|
added bug |
2018-10-08 19:14:56 |
Mauricio Faria de Oliveira |
summary |
regression in 'ip --family bridge neigh' since linux v4.12+ |
regression in 'ip --family bridge neigh' since linux v4.12 |
|
2018-10-08 19:27:37 |
Mauricio Faria de Oliveira |
description |
[Impact]
* Netlink RTM_GETNEIGH requests for PF_BRIDGE are broken since linux v4.12.
* Users, tools (e.g., iproute2), and libraries (e.g., go netlink) that use
such request/family currently receive nothing back in the kernel response.
* The upstream fix resolves the breakage in the userspace-kernel interface
by explicitly checking for the old/broken request to ensure it's replied.
[Test Case]
* The command 'ip --family bridge neigh' returns nothing on broken kernels,
and matches 'bridge fdb show' on fixed kernels.
* Before:
$ ip --family bridge neigh
$
* After:
$ ip --family bridge neigh
dev ens3 lladdr 33:33:00:00:00:01 PERMANENT
dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT
dev ens3 lladdr 33:33:ff:e9:9d:60 PERMANENT
* Reference:
$ bridge fdb show
33:33:00:00:00:01 dev ens3 self permanent
01:00:5e:00:00:01 dev ens3 self permanent
33:33:ff:e9:9d:60 dev ens3 self permanent
[Regression Potential]
* Low, for three reasons:
* The fix is contained in the RTM_GETNEIGH request for PF_BRIDGE family,
which is apparently not very used (this regression has existed between
v4.12 and v4.19).
* The checks introduced by the fix are conservative, based on the size
of the old request (the size of the old/new requests are different),
and it does nothing different in case the (old) size doesn't match.
* Given the above, only applications with message length and contents
specially hand-crafted (and likely not valid nor useful) might fail.
To the best of my knowledge, this is not the common case out there.
[Other Info]
* The patch is only applicable to v4.12+ (so not Trusty nor Xenial).
* The patch is the same for Bionic, Cosmic, and unstable.
* Upstream commit: bd961c9bc664 ("rtnetlink: fix rtnl_fdb_dump() for ndmsg header")
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd961c9bc66497f0c63f4ba1d02900bb85078366
* I'll submit the patch shortly to the kernel-team mailing list. |
[Impact]
* Netlink RTM_GETNEIGH requests for PF_BRIDGE are broken since linux v4.12.
* Users, tools (e.g., iproute2), and libraries (e.g., go netlink) that use
such request/family currently receive nothing back in the kernel response.
* The upstream fix resolves the breakage in the userspace-kernel interface
by explicitly checking for the old/broken request to ensure it's replied.
[Test Case]
* The command 'ip --family bridge neigh' returns nothing on broken kernels,
and matches 'bridge fdb show' on fixed kernels.
* Before:
$ ip --family bridge neigh
$
* After:
$ ip --family bridge neigh
dev ens3 lladdr 33:33:00:00:00:01 PERMANENT
dev ens3 lladdr 01:00:5e:00:00:01 PERMANENT
dev ens3 lladdr 33:33:ff:e9:9d:60 PERMANENT
* Reference:
$ bridge fdb show
33:33:00:00:00:01 dev ens3 self permanent
01:00:5e:00:00:01 dev ens3 self permanent
33:33:ff:e9:9d:60 dev ens3 self permanent
[Regression Potential]
* Low, for three reasons:
* The fix is fairly contained (RTM_GETNEIGH request for PF_BRIDGE family).
* The checks introduced by the fix are conservative, based on the size
of the old request (the size of the old/new requests are different),
and it does nothing different in case the (old) size doesn't match.
* Given the above, only applications with message length and contents
specially hand-crafted (and likely not valid nor useful) might fail.
To the best of my knowledge, this is not the common case out there.
[Other Info]
* The patch is only applicable to v4.12+ (so not Trusty nor Xenial).
* The patch is the same for Bionic, Cosmic, and unstable.
* Upstream commit: bd961c9bc664 ("rtnetlink: fix rtnl_fdb_dump() for ndmsg header")
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bd961c9bc66497f0c63f4ba1d02900bb85078366
* I'll submit the patch shortly to the kernel-team mailing list. |
|
2018-10-08 19:30:04 |
Ubuntu Kernel Bot |
linux (Ubuntu): status |
New |
Incomplete |
|
2018-10-08 19:35:49 |
Mauricio Faria de Oliveira |
linux (Ubuntu): status |
Incomplete |
Confirmed |
|
2018-10-09 06:48:17 |
Stefan Bader |
nominated for series |
|
Ubuntu Bionic |
|
2018-10-09 06:48:17 |
Stefan Bader |
bug task added |
|
linux (Ubuntu Bionic) |
|
2018-10-09 17:25:07 |
Joseph Salisbury |
linux (Ubuntu Bionic): status |
New |
Triaged |
|
2018-10-09 17:25:09 |
Joseph Salisbury |
linux (Ubuntu): status |
Confirmed |
Triaged |
|
2018-10-09 17:25:12 |
Joseph Salisbury |
linux (Ubuntu): importance |
Undecided |
Medium |
|
2018-10-09 17:25:15 |
Joseph Salisbury |
linux (Ubuntu Bionic): importance |
Undecided |
Medium |
|
2018-10-23 14:47:33 |
Kleber Sacilotto de Souza |
linux (Ubuntu Bionic): status |
Triaged |
Fix Committed |
|
2018-10-24 13:35:14 |
Brad Figg |
tags |
|
verification-needed-bionic |
|
2018-10-24 14:50:14 |
Brad Figg |
tags |
verification-needed-bionic |
verification-needed-bionic verification-needed-cosmic |
|
2018-10-24 22:11:43 |
Mauricio Faria de Oliveira |
tags |
verification-needed-bionic verification-needed-cosmic |
verification-done-bionic verification-done-cosmic |
|
2018-11-07 10:15:02 |
Stefan Bader |
nominated for series |
|
Ubuntu Cosmic |
|
2018-11-07 10:15:02 |
Stefan Bader |
bug task added |
|
linux (Ubuntu Cosmic) |
|
2018-11-07 10:15:15 |
Stefan Bader |
linux (Ubuntu Cosmic): importance |
Undecided |
Medium |
|
2018-11-07 10:15:15 |
Stefan Bader |
linux (Ubuntu Cosmic): status |
New |
Fix Committed |
|
2018-11-13 18:51:26 |
Launchpad Janitor |
linux (Ubuntu Bionic): status |
Fix Committed |
Fix Released |
|
2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2017-13168 |
|
2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-15471 |
|
2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-16658 |
|
2018-11-13 18:51:26 |
Launchpad Janitor |
cve linked |
|
2018-9363 |
|
2018-11-13 19:09:36 |
Launchpad Janitor |
linux (Ubuntu Cosmic): status |
Fix Committed |
Fix Released |
|
2018-11-17 03:22:23 |
Launchpad Janitor |
linux (Ubuntu): status |
Triaged |
Fix Released |
|