linux-stable.git/include/uapi/linux/if_link.h, branch v6.18.40

bonding: 3ad: add lacp_strict configuration knob

2026-07-24T14:16:07+00:00

[ Upstream commit 32b0b8953343eaceaa816a9ead3b6bb66355c64e ]

When an 802.3ad (LACP) bonding interface has no slaves in the
collecting/distributing state, the bonding master still reports
carrier as up as long as at least 'min_links' slaves have carrier.

In this situation, only one slave is effectively used for TX/RX,
while traffic received on other slaves is dropped. Upper-layer
daemons therefore consider the interface operational, even though
traffic may be blackholed if the lack of LACP negotiation means
the partner is not ready to deal with traffic.

Introduce a configuration knob to control this behavior. It allows
the bonding master to assert carrier only when at least 'min_links'
slaves are in Collecting_Distributing state.

The default mode preserves the existing behavior. This patch only
introduces the knob; its behavior is implemented in the subsequent
commit.

Fixes: 655f8919d549 ("bonding: add min links parameter to 802.3ad")
Signed-off-by: Louis Scalbert 
Acked-by: Jay Vosburgh 
Link: https://patch.msgid.link/20260603150331.1919611-4-louis.scalbert@6wind.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Sasha Levin

bonding: print churn state via netlink

2026-05-23T11:07:12+00:00

[ Upstream commit 4916f2e2f3fc9aef289fcd07949301e5c29094c2 ]

Currently, the churn state is printed only in sysfs. Add netlink support
so users could get the state via netlink.

Signed-off-by: Hangbin Liu 
Link: https://patch.msgid.link/20260224020215.6012-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni 
Stable-dep-of: c4f050ce06c5 ("bonding: 3ad: implement proper RCU rules for port->aggregator")
Signed-off-by: Sasha Levin

rtnetlink: add needed_{head,tail}room attributes

2025-09-20T00:21:55+00:00

Various network interface types make use of needed_{head,tail}room values
to efficiently reserve buffer space for additional encapsulation headers,
such as VXLAN, Geneve, IPSec, etc. However, it is not currently possible
to query these values in a generic way.

Introduce ability to query the needed_{head,tail}room values of a network
device via rtnetlink, such that applications that may wish to use these
values can do so.

For example, Cilium agent iterates over present devices based on user config
(direct routing, vxlan, geneve, wireguard etc.) and in future will configure
netkit in order to expose the needed_{head,tail}room into K8s pods. See
b9ed315d3c4c ("netkit: Allow for configuring needed_{head,tail}room").

Suggested-by: Daniel Borkmann 
Signed-off-by: Alasdair McWilliam 
Reviewed-by: Daniel Borkmann 
Link: https://patch.msgid.link/20250917095543.14039-1-alasdair@mcwilliam.dev
Signed-off-by: Jakub Kicinski

bonding: add support for per-port LACP actor priority

2025-09-09T08:56:02+00:00

Introduce a new netlink attribute 'actor_port_prio' to allow setting
the LACP actor port priority on a per-slave basis. This extends the
existing bonding infrastructure to support more granular control over
LACP negotiations.

The priority value is embedded in LACPDU packets and will be used by
subsequent patches to influence aggregator selection policies.

Signed-off-by: Hangbin Liu 
Link: https://patch.msgid.link/20250902064501.360822-2-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni

net: bonding: add broadcast_neighbor netlink option

2025-07-08T08:59:42+00:00

User can config or display the bonding broadcast_neighbor option via
iproute2/netlink.

Cc: Jay Vosburgh 
Cc: "David S. Miller" 
Cc: Eric Dumazet 
Cc: Jakub Kicinski 
Cc: Paolo Abeni 
Cc: Simon Horman 
Cc: Jonathan Corbet 
Cc: Andrew Lunn 
Cc: Steven Rostedt 
Cc: Masami Hiramatsu 
Cc: Mathieu Desnoyers 
Cc: Nikolay Aleksandrov 
Signed-off-by: Tonghao Zhang 
Signed-off-by: Zengbing Tu 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/76b90700ba5b98027dfb51a2f3c5cfea0440a21b.1751031306.git.tonghao@bamaicloud.com
Signed-off-by: Paolo Abeni

vxlan: Support MC routing in the underlay

2025-06-18T01:18:46+00:00

Locally-generated MC packets have so far not been subject to MC routing.
Instead an MC-enabled installation would maintain the MC routing tables,
and separately from that the list of interfaces to send packets to as part
of the VXLAN FDB and MDB.

In a previous patch, a ip_mr_output() and ip6_mr_output() routines were
added for IPv4 and IPv6. All locally generated MC traffic is now passed
through these functions. For reasons of backward compatibility, an SKB
(IPCB / IP6CB) flag guards the actual MC routing.

This patch adds logic to set the flag, and the UAPI to enable the behavior.

Signed-off-by: Petr Machata 
Reviewed-by: Ido Schimmel 
Reviewed-by: Nikolay Aleksandrov 
Link: https://patch.msgid.link/d899655bb7e9b2521ee8c793e67056b9fd02ba12.1750113335.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski

ovpn: add basic interface creation/destruction/management routines

2025-04-17T10:30:02+00:00

Add basic infrastructure for handling ovpn interfaces.

Tested-by: Donald Hunter 
Signed-off-by: Antonio Quartulli 
Link: https://patch.msgid.link/20250415-b4-ovpn-v26-3-577f6097b964@openvpn.net
Reviewed-by: Sabrina Dubroca 
Tested-by: Oleksandr Natalenko 
Signed-off-by: Paolo Abeni

net: advertise netns_immutable property via netlink

2025-03-04T11:44:48+00:00

Since commit 05c1280a2bcf ("netdev_features: convert NETIF_F_NETNS_LOCAL to
dev->netns_local"), there is no way to see if the netns_immutable property
s set on a device. Let's add a netlink attribute to advertise it.

Signed-off-by: Nicolas Dichtel 
Reviewed-by: Eric Dumazet 
Reviewed-by: Alexander Lobakin 
Reviewed-by: Kuniyuki Iwashima 
Signed-off-by: Paolo Abeni

geneve: Allow users to specify source port range

2025-02-28T00:54:54+00:00

Recently, in case of Cilium, we run into users on Azure who require to use
tunneling for east/west traffic due to hitting IPAM API limits for Kubernetes
Pods if they would have gone with publicly routable IPs for Pods. In case
of tunneling, Cilium supports the option of vxlan or geneve. In order to
RSS spread flows among remote CPUs both derive a source port hash via
udp_flow_src_port() which takes the inner packet's skb->hash into account.
For clusters with many nodes, this can then hit a new limitation [0]: Today,
the Azure networking stack supports 1M total flows (500k inbound and 500k
outbound) for a VM. [...] Once this limit is hit, other connections are
dropped. [...] Each flow is distinguished by a 5-tuple (protocol, local IP
address, remote IP address, local port, and remote port) information. [...]

For vxlan and geneve, this can create a massive amount of UDP flows which
then run into the limits if stale flows are not evicted fast enough. One
option to mitigate this for vxlan is to narrow the source port range via
IFLA_VXLAN_PORT_RANGE while still being able to benefit from RSS. However,
geneve currently does not have this option and it spreads traffic across
the full source port range of [1, USHRT_MAX]. To overcome this limitation
also for geneve, add an equivalent IFLA_GENEVE_PORT_RANGE setting for users.

Note that struct geneve_config before/after still remains at 2 cachelines
on x86-64. The low/high members of struct ifla_geneve_port_range (which is
uapi exposed) are of type __be16. While they would be perfectly fine to be
of __u16 type, the consensus was that it would be good to be consistent
with the existing struct ifla_vxlan_port_range from a uapi consumer PoV.

Signed-off-by: Daniel Borkmann 
Link: https://learn.microsoft.com/en-us/azure/virtual-network/virtual-machine-network-throughput [0]
Link: https://patch.msgid.link/20250226182030.89440-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski

Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2025-01-07T23:39:09+00:00

Daniel Borkmann says:

====================
pull-request: bpf-next 2025-01-07

We've added 7 non-merge commits during the last 32 day(s) which contain
a total of 11 files changed, 190 insertions(+), 103 deletions(-).

The main changes are:

1) Migrate the test_xdp_meta.sh BPF selftest into test_progs
   framework, from Bastien Curutchet.

2) Add ability to configure head/tailroom for netkit devices,
   from Daniel Borkmann.

3) Fixes and improvements to the xdp_hw_metadata selftest,
   from Song Yoong Siang.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
  selftests/bpf: Extend netkit tests to validate set {head,tail}room
  netkit: Add add netkit {head,tail}room to rt_link.yaml
  netkit: Allow for configuring needed_{head,tail}room
  selftests/bpf: Migrate test_xdp_meta.sh into xdp_context_test_run.c
  selftests/bpf: test_xdp_meta: Rename BPF sections
  selftests/bpf: Enable Tx hwtstamp in xdp_hw_metadata
  selftests/bpf: Actuate tx_metadata_len in xdp_hw_metadata
====================

Link: https://patch.msgid.link/20250107130908.143644-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski