linux-next.git/drivers/net/ipvlan/ipvlan.h, branch master

ipvlan: Support per-netns netdev unregistration.

2026-07-11T10:57:50+00:00

When a lower device is unregistered, its upper ipvlan devices must also be unregistered. However, these upper devices may reside in different netns than the lower device. Let's use unregister_netdevice_queue_net() to support per-netns device unregistration for ipvlan. The new dying flag in struct ipvl_dev is used to avoid a race that ipvlan_link_delete() is called while its lower device is being removed in ipvlan_device_event(). If dying is true in ipvlan_link_delete(), the ipvlan device is already destructed but not yet unregistered. In this case, unregistration will be done in __rtnl_net_unlock() of the ->dellink() caller. Tested: 1. Create veth in ns1 and two ipvlan devices in ns2 and ns3. # ip netns add ns1 # ip netns add ns2 # ip netns add ns3 # ip -n ns1 link add veth0 type veth peer veth1 # ip -n ns2 link add ipvl2 link veth0 link-netns ns1 type ipvlan mode l2 # ip -n ns3 link add ipvl3 link veth0 link-netns ns1 type ipvlan mode l2 2. Run bpftrace to check that veth is unregistered first but wait ipvlan to be unregistered # bpftrace -e '#include kprobe:ipvlan_uninit, kprobe:veth_dellink, kprobe:free_netdev { $dev = (struct net_device *)arg0; printf("PID: %d | DEV: %s%s\n", pid, $dev->name, kstack()); }' 3. Remove the lower veth0 in ns1. # ip -n ns1 link del veth0 We can see that veth0 is freed after unregistering ipvl2 and ipvl3 in per-netns work because ipvl_port holds refcount of veth0. PID: 2010 | DEV: veth0 veth_dellink+5 rtnl_dellink+1213 rtnetlink_rcv_msg+1791 ... PID: 440 | DEV: ipvl2 ipvlan_uninit+5 unregister_netdevice_many_notify+7129 unregister_netdevice_many_net+1050 rtnl_net_work_func+136 process_scheduled_works+2538 ... PID: 440 | DEV: ipvl2 free_netdev+5 netdev_run_todo+4798 process_scheduled_works+2538 ... PID: 440 | DEV: ipvl3 ipvlan_uninit+5 unregister_netdevice_many_notify+7129 unregister_netdevice_many_net+1050 rtnl_net_work_func+136 process_scheduled_works+2538 ... PID: 2010 | DEV: veth0 free_netdev+5 netdev_run_todo+4798 rtnl_dellink+1507 rtnetlink_rcv_msg+1791 ... PID: 440 | DEV: ipvl3 free_netdev+5 netdev_run_todo+4798 process_scheduled_works+2538 ... Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260703001009.1572444-15-kuniyu@google.com Signed-off-by: Paolo Abeni

ipvlan: Protect ipvl_port.ipvlans with mutex.

2026-07-11T10:57:50+00:00

struct ipvl_port is shared between a lower device and its upper ipvlan devices. All upper devices are linked to ipvl_port.ipvlans. Once RTNL is removed, the list can be modified concurrently from different netns due to device removal. Let's protect it with a per-port mutex. NETDEV_PRECHANGEUPPER and NETDEV_CHANGEUPPER are explicitly skipped to avoid deadlock for netdev_upper_dev_unlink() called from NETDEV_UNREGISTER. Note that __ipvtap_dellink_ptr is added for CONFIG_IPVLAN=y but CONFIG_TAP=m and CONFIG_IPVTAP=m. Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260703001009.1572444-14-kuniyu@google.com Signed-off-by: Paolo Abeni

ipvlan: Convert ipvl_port.count to refcount_t.

2026-07-11T10:57:50+00:00

struct ipvl_port is shared between a lower device and its upper ipvlan devices. While each upper device can always access ipvl_port safely via ipvlan_dev.port, the lower device relies on RTNL to access it via net_device.rx_handler_data. Once RTNL is removed, the lower device cannot read ipvl_port safely in ipvlan_device_event() because the port could be freed concurrently and net_device.rx_handler_data is set to NULL if the last ipvlan device in another namespace is unregistered. Let's convert ipvl_port.count to refcount_t and use RCU along with refcount_inc_not_zero() in ipvlan_device_event(). netdev_put() in ipvlan_port_destroy() is also moved down after cancel_work_sync(), which is the last user of port->dev. Note that ipvlan->port is now set in ipvlan_init() so that it can be used in ipvlan_uninit(), instead of ipvlan_port_get_rtnl() (rtnl_dereference()). Signed-off-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260703001009.1572444-12-kuniyu@google.com Signed-off-by: Paolo Abeni

ipvlan: Make the addrs_lock be per port

2026-01-19T18:03:30+00:00

Make the addrs_lock be per port, not per ipvlan dev. Initial code seems to be written in the assumption, that any address change must occur under RTNL. But it is not so for the case of IPv6. So 1) Introduce per-port addrs_lock. 2) It was needed to fix places where it was forgotten to take lock (ipvlan_open/ipvlan_close) This appears to be a very minor problem though. Since it's highly unlikely that ipvlan_add_addr() will be called on 2 CPU simultaneously. But nevertheless, this could cause: 1) False-negative of ipvlan_addr_busy(): one interface iterated through all port->ipvlans + ipvlan->addrs under some ipvlan spinlock, and another added IP under its own lock. Though this is only possible for IPv6, since looks like only ipvlan_addr6_event() can be called without rtnl_lock. 2) Race since ipvlan_ht_addr_add(port) is called under different ipvlan->addrs_lock locks This should not affect performance, since add/remove IP is a rare situation and spinlock is not taken on fast paths. Fixes: 8230819494b3 ("ipvlan: use per device spinlock to protect addrs list updates") Signed-off-by: Dmitry Skorodumov Reviewed-by: Paolo Abeni Link: https://patch.msgid.link/20260112142417.4039566-2-skorodumov.dmitry@huawei.com Signed-off-by: Jakub Kicinski

rtnetlink: Pack newlink() params into struct

2025-02-21T23:28:02+00:00

There are 4 net namespaces involved when creating links: - source netns - where the netlink socket resides, - target netns - where to put the device being created, - link netns - netns associated with the device (backend), - peer netns - netns of peer device. Currently, two nets are passed to newlink() callback - "src_net" parameter and "dev_net" (implicitly in net_device). They are set as follows, depending on netlink attributes in the request. +------------+-------------------+---------+---------+ | peer netns | IFLA_LINK_NETNSID | src_net | dev_net | +------------+-------------------+---------+---------+ | | absent | source | target | | absent +-------------------+---------+---------+ | | present | link | link | +------------+-------------------+---------+---------+ | | absent | peer | target | | present +-------------------+---------+---------+ | | present | peer | link | +------------+-------------------+---------+---------+ When IFLA_LINK_NETNSID is present, the device is created in link netns first and then moved to target netns. This has some side effects, including extra ifindex allocation, ifname validation and link events. These could be avoided if we create it in target netns from the beginning. On the other hand, the meaning of src_net parameter is ambiguous. It varies depending on how parameters are passed. It is the effective link (or peer netns) by design, but some drivers ignore it and use dev_net instead. To provide more netns context for drivers, this patch packs existing newlink() parameters, along with the source netns, link netns and peer netns, into a struct. The old "src_net" is renamed to "net" to avoid confusion with real source netns, and will be deprecated later. The use of src_net are converted to params->net trivially. Signed-off-by: Xiao Liang Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20250219125039.18024-3-shaw.leon@gmail.com Signed-off-by: Jakub Kicinski

ipvlan: hold lower dev to avoid possible use-after-free

2022-11-18T10:39:22+00:00

Recently syzkaller discovered the issue of disappearing lower device (NETDEV_UNREGISTER) while the virtual device (like macvlan) is still having it as a lower device. So it's just a matter of time similar discovery will be made for IPvlan device setup. So fixing it preemptively. Also while at it, add a refcount tracker. Fixes: 2ad7bf363841 ("ipvlan: Initial check-in of the IPVLAN driver.") Signed-off-by: Mahesh Bandewar Signed-off-by: David S. Miller

ipvlan: adopt u64_stats_t

2022-06-10T04:53:10+00:00

As explained in commit 316580b69d0a ("u64_stats: provide u64_stats_t type") we should use u64_stats_t and related accessors to avoid load/store tearing. Add READ_ONCE() when reading rx_errs & tx_drps. Signed-off-by: Eric Dumazet Signed-off-by: Jakub Kicinski

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman

ipvlan: decouple l3s mode dependencies from other modes

2019-02-08T19:16:48+00:00

Right now ipvlan has a hard dependency on CONFIG_NETFILTER and otherwise it cannot be built. However, the only ipvlan operation mode that actually depends on netfilter is l3s, everything else is independent of it. Break this hard dependency such that users are able to use ipvlan l3 mode on systems where netfilter is not compiled in. Therefore, this adds a hidden CONFIG_IPVLAN_L3S bool which is defaulting to y when CONFIG_NETFILTER is set in order to retain existing behavior for l3s. All l3s related code is refactored into ipvlan_l3s.c that is compiled in when enabled. Signed-off-by: Daniel Borkmann Cc: Mahesh Bandewar Cc: Florian Westphal Cc: Martynas Pumputis Acked-by: Florian Westphal Signed-off-by: David S. Miller

ipvlan: properly annotate rx_handler access

2018-03-08T16:12:43+00:00

The rx_handler field is rcu-protected, but I forgot to use the proper accessor while refactoring netif_is_ipvlan_port(). Such function only check the rx_handler value, so it is safe, but we need to properly read rx_handler via rcu_access_pointer() to avoid sparse warnings. Fixes: 1ec54cb44e67 ("net: unpollute priv_flags space") Signed-off-by: Paolo Abeni Signed-off-by: David S. Miller