netdev - [RFC net-next v2 0/7] openvswitch: add drop reasons

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date: Tue,  1 Aug 2023 17:16:41 +0200
From: Adrian Moreno <amorenoz@...hat.com>
To: netdev@...r.kernel.org
Cc: Adrian Moreno <amorenoz@...hat.com>,
	aconole@...hat.com,
	i.maximets@....org,
	eric@...ver.life,
	dev@...nvswitch.org
Subject: [RFC net-next v2 0/7] openvswitch: add drop reasons

There is currently a gap in drop visibility in the openvswitch module.
This series tries to improve this by adding a new drop reason subsystem
for OVS.

Apart from adding a new drop reasson subsystem and some common drop
reasons, this series takes Eric's preliminary work [1] on adding an
explicit drop action and integrates it into the same subsystem.

This series also adds some selftests and so it requires [2] to be
applied first.

A limitation of this series is that it does not report upcall errors.
The reason is that there could be many sources of upcall drops and the
most common one, which is the netlink buffer overflow, cannot be
reported via kfree_skb() because the skb is freed in the netlink layer
(see [3]). Therefore, using a reason for the rare events and not the
common one would be even more misleading. I'd propose we add (in a
follow up patch) a tracepoint to better report upcall errors.

[1] https://lore.kernel.org/netdev/202306300609.tdRdZscy-lkp@intel.com/T/
[2] https://lore.kernel.org/all/20230728115940.578658-1-aconole@redhat.com/
[3] commit 1100248a5c5c ("openvswitch: Fix double reporting of drops in dropwatch")

---
rfc1 -> rfc2:
- Fail when an explicit drop is not the last
- Added a drop reason for action errors
- Added braces around macros
- Dropped patch that added support for masks in ovs-dpctl.py as it's now
  included in Aaron's series [2].

Adrian Moreno (6):
  net: openvswitch: add datapath flow drop reason
  net: openvswitch: add action error drop reason
  net: openvswitch: add meter drop reason
  net: openvswitch: add misc error drop reasons
  selftests: openvswitch: add drop reason testcase
  selftests: openvswitch: add explicit drop testcase

Eric Garver (1):
  net: openvswitch: add explicit drop action

 include/net/dropreason.h                      |  6 ++
 include/uapi/linux/openvswitch.h              |  2 +
 net/openvswitch/actions.c                     | 42 ++++++---
 net/openvswitch/conntrack.c                   |  3 +-
 net/openvswitch/datapath.c                    | 16 ++++
 net/openvswitch/drop.h                        | 34 +++++++
 net/openvswitch/flow_netlink.c                | 10 +-
 .../selftests/net/openvswitch/openvswitch.sh  | 92 ++++++++++++++++++-
 .../selftests/net/openvswitch/ovs-dpctl.py    | 22 ++++-
 9 files changed, 209 insertions(+), 18 deletions(-)
 create mode 100644 net/openvswitch/drop.h

-- 
2.41.0