IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
If packet headers changed, the cached nfct is no longer relevant
for the packet and attempt to re-use it leads to the incorrect packet
classification.
This issue is causing broken connectivity in OpenStack deployments
with OVS/OVN due to hairpin traffic being unexpectedly dropped.
The setup has datapath flows with several conntrack actions and tuple
changes between them:
actions:ct(commit,zone=8,mark=0/0x1,nat(src)),
set(eth(src=00:00:00:00:00:01,dst=00:00:00:00:00:06)),
set(ipv4(src=172.18.2.10,dst=192.168.100.6,ttl=62)),
ct(zone=8),recirc(0x4)
After the first ct() action the packet headers are almost fully
re-written. The next ct() tries to re-use the existing nfct entry
and marks the packet as invalid, so it gets dropped later in the
pipeline.
Clearing the cached conntrack entry whenever packet tuple is changed
to avoid the issue.
The flow key should not be cleared though, because we should still
be able to match on the ct_state if the recirculation happens after
the tuple change but before the next ct() action.
Cc: stable@vger.kernel.org
Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action")
Reported-by: Frode Nordahl <frode.nordahl@canonical.com>
Link: https://mail.openvswitch.org/pipermail/ovs-discuss/2022-May/051829.html
Link: https://bugs.launchpad.net/ubuntu/+source/ovn/+bug/1967856
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Link: https://lore.kernel.org/r/20220606221140.488984-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>