kernel/linux.git/net/core/netdev-genl.c, branch v7.2-rc1

netdev-genl: report NAPI thread PID in the caller's pid namespace

2026-06-17T23:09:32+00:00

netdev_nl_napi_fill_one() reports the NAPI kthread PID in NETDEV_A_NAPI_PID using task_pid_nr(), which returns the PID in the initial pid namespace. NETDEV_CMD_NAPI_GET does not have GENL_ADMIN_PERM and the netdev genl family is netnsok, so a caller in a child pid namespace can issue it. That caller then sees the kthread's global PID, even though the kthread is not visible in its pid namespace, where the value should be 0. Translate the PID through the caller's pid namespace, the same way commit 3799c2570982 ("io_uring/fdinfo: translate SqThread PID through caller's pid_ns") did for the io_uring SQPOLL thread. The doit and dumpit paths both run synchronously in the caller's context, so task_active_pid_ns(current) is the caller's pid namespace. Fixes: db4704f4e4df ("netdev-genl: Add PID for the NAPI thread") Cc: stable@vger.kernel.org Signed-off-by: Maoyi Xie Reviewed-by: Joe Damato Reviewed-by: Samiullah Khawaja Link: https://patch.msgid.link/20260615171736.1709318-1-maoyixie.tju@gmail.com Signed-off-by: Jakub Kicinski

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2026-06-11T21:33:35+00:00

Cross-merge networking fixes after downstream PR (net-7.1-rc8). Conflicts: drivers/net/ethernet/wangxun/txgbe/txgbe_aml.c f67aead16e85 ("net: txgbe: rework service event handling") 57d39faed4c9 ("net: txgbe: improve functions of AML 40G devices") net/rds/info.c 512db8267b73 ("rds: mark snapshot pages dirty in rds_info_getsockopt()") 6e94eeb2a2a6 ("rds: convert to getsockopt_iter") Adjacent changes: include/net/sock.h 1ee90b77b727 ("net: guard timestamp cmsgs to real error queue skbs") f0de88303d5e ("net: make is_skb_wmem() available to modules") Signed-off-by: Jakub Kicinski

netdev: fix double-free in netdev_nl_bind_rx_doit()

2026-06-09T00:40:20+00:00

Sashiko flags that genlmsg_reply() always consumes the skb. The error path calls nlmsg_free(rsp) so we can't jump directly to it. Let's not unbind, just propagate the error to the user. This is the typical way of handling genlmsg_reply() failures. They shouldn't happen unless user does something silly like calling the kernel with an already-full rcvbuf. Reported-by: Sashiko Fixes: 170aafe35cb9 ("netdev: support binding dma-buf to netdevice") Reviewed-by: Bobby Eshleman Acked-by: Daniel Borkmann Reviewed-by: Nikolay Aleksandrov Signed-off-by: Jakub Kicinski

net: devmem: support TX over NETMEM_TX_NO_DMA devices

2026-05-19T01:49:06+00:00

When a netkit virtual device leases queues from a physical NIC, devmem TX bindings created on the netkit device must still result in the dmabuf being mapped for dma by the physical device. This patch accomplishes this by teaching the bind handler to search for the underlying DMA-capable device by looking it up via leased rx queues. The function netdev_find_netmem_tx_dev(), used for finding the underlying DMA-capable device, can be extended to support other non-netkit NETMEM_TX_NO_DMA devices in the future if needed. Additionally, this patch extends validate_xmit_unreadable_skb() to support the netkit case, where the skb is validated twice: once on the netkit guest device and again on the physical NIC after BPF redirect or ip forwarding. Acked-by: Stanislav Fomichev Signed-off-by: Bobby Eshleman Link: https://patch.msgid.link/20260514-tcp-dm-netkit-v5-3-408c59b91e66@meta.com Signed-off-by: Jakub Kicinski

net: convert netmem_tx flag to enum

2026-05-19T01:49:06+00:00

Devices that support netmem TX previously set dev->netmem_tx = true. This was checked in validate_xmit_unreadable_skb() to drop unreadable skbs (skbs with dmabuf-backed frags) before they reach drivers that would mishandle them or devices that would not have the iommu mappings for them. A subsequent patch will introduce a third state for virtual devices that forward unreadable skbs without ever performing DMA on them. To prepare for that, convert the boolean dev->netmem_tx into an enum: NETMEM_TX_NONE - no netmem TX support (drop unreadable skbs) NETMEM_TX_DMA - full support, device does DMA Update the existing NIC drivers (bnxt, gve, mlx5, fbnic) and the validators in net/core to use the new enum. No functional change. Acked-by: Harshitha Ramamurthy Acked-by: Stanislav Fomichev Signed-off-by: Bobby Eshleman Link: https://patch.msgid.link/20260514-tcp-dm-netkit-v5-1-408c59b91e66@meta.com Signed-off-by: Jakub Kicinski

net: remove the netif_get_rx_queue_lease_locked() helpers

2026-04-10T01:26:28+00:00

The netif_get_rx_queue_lease_locked() API hides the locking and the descend onto the leased queue. Making the code harder to follow (at least to me). Remove the API and open code the descend a bit. Most of the code now looks like: if (!leased) return __helper(x); hw_rxq = .. netdev_lock(hw_rxq->dev); ret = __helper(x); netdev_unlock(hw_rxq->dev); return ret; Of course if we have more code paths that need the wrapping we may need to revisit. For now, IMHO, having to know what netif_get_rx_queue_lease_locked() does is not worth the 20LoC it saves. Link: https://patch.msgid.link/20260408151251.72bd2482@kernel.org Signed-off-by: Jakub Kicinski

net: Proxy netdev_queue_get_dma_dev for leased queues

2026-04-10T01:21:46+00:00

Extend netdev_queue_get_dma_dev to return the physical device of the real rxq for DMA in case the queue was leased. This allows memory providers like io_uring zero-copy or devmem to bind to the physically leased rxq via virtual devices such as netkit. Signed-off-by: David Wei Co-developed-by: Daniel Borkmann Signed-off-by: Daniel Borkmann Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260402231031.447597-8-daniel@iogearbox.net Signed-off-by: Jakub Kicinski

net: Add lease info to queue-get response

2026-04-10T01:21:46+00:00

Populate nested lease info to the queue-get response that returns the ifindex, queue id with type and optionally netns id if the device resides in a different netns. Example with ynl client when using AF_XDP via queue leasing: # ip a [...] 4: enp10s0f0np0: mtu 1500 xdp/id:24 qdisc mq state UP group default qlen 1000 link/ether e8:eb:d3:a3:43:f6 brd ff:ff:ff:ff:ff:ff inet 10.0.0.2/24 scope global enp10s0f0np0 valid_lft forever preferred_lft forever inet6 fe80::eaeb:d3ff:fea3:43f6/64 scope link proto kernel_ll valid_lft forever preferred_lft forever [...] # ethtool -i enp10s0f0np0 driver: mlx5_core [...] # ynl --family netdev --output-json --do queue-get \ --json '{"ifindex": 4, "id": 15, "type": "rx"}' {'id': 15, 'ifindex': 4, 'lease': {'ifindex': 8, 'netns-id': 0, 'queue': {'id': 1, 'type': 'rx'}}, 'napi-id': 8227, 'type': 'rx', 'xsk': {}} # ip netns list foo (id: 0) # ip netns exec foo ip a [...] 8: nk@NONE: mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff inet6 fe80::200:ff:fe00:0/64 scope link proto kernel_ll valid_lft forever preferred_lft forever [...] # ip netns exec foo ethtool -i nk driver: netkit [...] # ip netns exec foo ls /sys/class/net/nk/queues/ rx-0 rx-1 tx-0 # ip netns exec foo ynl --family netdev --output-json --do queue-get \ --json '{"ifindex": 8, "id": 1, "type": "rx"}' {"id": 1, "type": "rx", "ifindex": 8, "xsk": {}} Note that the caller of netdev_nl_queue_fill_one() holds the netdevice lock. For the queue-get we do not lock both devices. When queues get {un,}leased, both devices are locked, thus if __netif_get_rx_queue_lease() returns a lease pointer, it points to a valid device. The netns-id is fetched via peernet2id_alloc() similarly as done in OVS. Signed-off-by: Daniel Borkmann Co-developed-by: David Wei Signed-off-by: David Wei Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260402231031.447597-4-daniel@iogearbox.net Signed-off-by: Jakub Kicinski

net: Implement netdev_nl_queue_create_doit

2026-04-10T01:21:45+00:00

Implement netdev_nl_queue_create_doit which creates a new rx queue in a virtual netdev and then leases it to a rx queue in a physical netdev. Example with ynl client: # ynl --family netdev --output-json --do queue-create \ --json '{"ifindex": 8, "type": "rx", "lease": {"ifindex": 4, "queue": {"type": "rx", "id": 15}}}' {'id': 1} Note that the netdevice locking order is always from the virtual to the physical device. Signed-off-by: Daniel Borkmann Co-developed-by: David Wei Signed-off-by: David Wei Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20260402231031.447597-3-daniel@iogearbox.net Signed-off-by: Jakub Kicinski

net: Add queue-create operation

2026-04-10T01:21:45+00:00

Add a ynl netdev family operation called queue-create that creates a new queue on a netdevice: name: queue-create attribute-set: queue flags: [admin-perm] do: request: attributes: - ifindex - type - lease reply: &queue-create-op attributes: - id This is a generic operation such that it can be extended for various use cases in future. Right now it is mandatory to specify ifindex, the queue type which is enforced to rx and a lease. The newly created queue id is returned to the caller. A queue from a virtual device can have a lease which refers to another queue from a physical device. This is useful for memory providers and AF_XDP operations which take an ifindex and queue id to allow applications to bind against virtual devices in containers. The lease couples both queues together and allows to proxy the operations from a virtual device in a container to the physical device. In future, the nested lease attribute can be lifted and made optional for other use-cases such as dynamic queue creation for physical netdevs. The lack of lease and the specification of the physical device as an ifindex will imply that we need a real queue to be allocated. Similarly, the queue type enforcement to rx can then be lifted as well to support tx. An early implementation had only driver-specific integration [0], but in order for other virtual devices to reuse, it makes sense to have this as a generic API in core net. For leasing queues, the virtual netdev must have real_num_rx_queues less than num_rx_queues at the time of calling queue-create. The queue-type must be rx as only rx queues are supported for leasing for now. We also enforce that the queue-create ifindex must point to a virtual device, and that the nested lease attribute's ifindex must point to a physical device. The nested lease attribute set contains a netns-id attribute which is optional and can specify a netns-id relative to the caller's netns. It requires cap_net_admin and if the netns-id attribute is not specified, the lease ifindex will be retrieved from the current netns. Also, it is modeled as an s32 type similarly as done elsewhere in the stack. Signed-off-by: Daniel Borkmann Co-developed-by: David Wei Signed-off-by: David Wei Acked-by: Stanislav Fomichev Reviewed-by: Nikolay Aleksandrov Link: https://bpfconf.ebpf.io/bpfconf2025/bpfconf2025_material/lsfmmbpf_2025_netkit_borkmann.pdf [0] Link: https://patch.msgid.link/20260402231031.447597-2-daniel@iogearbox.net Signed-off-by: Jakub Kicinski