Use the typed random integer helpers instead of
get_random_bytes() when filling a single integer variable.
The helpers return the value directly, require no pointer
or size argument, and better express intent.
Skipped sites writing into __be16 (netdevsim) and __le64
(ceph) fields where a direct assignment would trigger
sparse endianness warnings.
Signed-off-by: David Carlier <devnexen@gmail.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260407150758.5889-1-devnexen@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 <kuba@kernel.org>
Daniel Borkmann says:
====================
netkit: Support for io_uring zero-copy and AF_XDP
Containers use virtual netdevs to route traffic from a physical netdev
in the host namespace. They do not have access to the physical netdev
in the host and thus can't use memory providers or AF_XDP that require
reconfiguring/restarting queues in the physical netdev.
This patchset adds the concept of queue leasing to virtual netdevs that
allow containers to use memory providers and AF_XDP at native speed.
Leased queues are bound to a real queue in a physical netdev and act
as a proxy.
Memory providers and AF_XDP operations take an ifindex and queue id,
so containers would pass in an ifindex for a virtual netdev and a queue
id of a leased queue, which then gets proxied to the underlying real
queue.
We have implemented support for this concept in netkit and tested the
latter against Nvidia ConnectX-6 (mlx5) as well as Broadcom BCM957504
(bnxt_en) 100G NICs. For more details see the individual patches.
====================
Link: https://patch.msgid.link/20260402231031.447597-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a netdevice notifier in netkit to watch for NETDEV_UNREGISTER events.
If the target device is indeed NETREG_UNREGISTERING and previously leased
a queue to a netkit device, then collect the related netkit devices and
batch-unregister_netdevice_many() them.
If this were not done, then the netkit device would hold a reference on
the physical device preventing it from going away. However, in case of
both io_uring zero-copy as well as AF_XDP this situation is handled
gracefully and the allocated resources are torn down.
In the case where mentioned infra is used through netkit, the applications
have a reference on netkit, and netkit in turn holds a reference on the
physical device. In order to have netkit release the reference on the
physical device, we need such watcher to then unregister the netkit ones.
This is generally quite similar to the dependency handling in case of
tunnels (e.g. vxlan bound to a underlying netdev) where the tunnel device
gets removed along with the physical device.
# ip a
[...]
4: enp10s0f0np0: <BROADCAST,MULTICAST> mtu 1500 qdisc mq state DOWN 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
[...]
8: nk@NONE: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
[...]
# rmmod mlx5_ib
# rmmod mlx5_core
[...]
[ 309.261822] mlx5_core 0000:0a:00.0 mlx5_0: Port: 1 Link DOWN
[ 344.235236] mlx5_core 0000:0a:00.1: E-Switch: Unload vfs: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
[ 344.246948] mlx5_core 0000:0a:00.1: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
[ 344.463754] mlx5_core 0000:0a:00.1: E-Switch: Disable: mode(LEGACY), nvfs(0), necvfs(0), active vports(0)
[ 344.770155] mlx5_core 0000:0a:00.1: E-Switch: cleanup
[...]
# ip a
[...]
[ both enp10s0f0np0 and nk gone ]
[...]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-13-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-8-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When a process in a container wants to setup a memory provider, it will
use the virtual netdev and a leased rxq, and call netif_mp_{open,close}_rxq
to try and restart the queue. At this point, proxy the queue restart on
the real rxq in the physical netdev.
For memory providers (io_uring zero-copy rx and devmem), it causes the
real rxq in the physical netdev to be filled from a memory provider that
has DMA mapped memory from a process within a container.
Signed-off-by: David Wei <dw@davidwei.uk>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-7-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net_mp_open_rxq is currently not used in the tree as all callers are
using __net_mp_open_rxq directly, and net_mp_close_rxq is only used
once while all other locations use __net_mp_close_rxq.
Consolidate into a single API, netif_mp_{open,close}_rxq, using the
netif_ prefix to indicate that the caller is responsible for locking.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-6-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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: <BROADCAST,MULTICAST,UP,LOWER_UP> 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: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> 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 <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-4-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260402231031.447597-3-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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 <daniel@iogearbox.net>
Co-developed-by: David Wei <dw@davidwei.uk>
Signed-off-by: David Wei <dw@davidwei.uk>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
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 <kuba@kernel.org>
sk_clone() initializes sk_tx_queue_mapping via sk_tx_queue_clear()
but does not initialize sk_rx_queue_mapping. Since this field is in
the sk_dontcopy region, it is neither copied from the parent socket
by sock_copy() nor zeroed by sk_prot_alloc() (called without
__GFP_ZERO from sk_clone).
Commit 03cfda4fa6 ("tcp: fix another uninit-value
(sk_rx_queue_mapping)") attempted to fix this by introducing
sk_mark_napi_id_set() with force_set=true in tcp_child_process().
However, sk_mark_napi_id_set() -> sk_rx_queue_set() only writes
when skb_rx_queue_recorded(skb) is true. If the 3-way handshake
ACK arrives through a device that does not record rx_queue (e.g.
loopback or veth), sk_rx_queue_mapping remains uninitialized.
When a subsequent data packet arrives with a recorded rx_queue,
sk_mark_napi_id() -> sk_rx_queue_update() reads the uninitialized
field for comparison (force_set=false path), triggering KMSAN.
This was reproduced by establishing a TCP connection over loopback
(which does not call skb_record_rx_queue), then attaching a BPF TC
program on lo ingress to set skb->queue_mapping on data packets:
BUG: KMSAN: uninit-value in tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1875)
tcp_v4_do_rcv (net/ipv4/tcp_ipv4.c:1875)
tcp_v4_rcv (net/ipv4/tcp_ipv4.c:2287)
ip_protocol_deliver_rcu (net/ipv4/ip_input.c:207)
ip_local_deliver_finish (net/ipv4/ip_input.c:242)
ip_local_deliver (net/ipv4/ip_input.c:262)
ip_rcv (net/ipv4/ip_input.c:573)
__netif_receive_skb (net/core/dev.c:6294)
process_backlog (net/core/dev.c:6646)
__napi_poll (net/core/dev.c:7710)
net_rx_action (net/core/dev.c:7929)
handle_softirqs (kernel/softirq.c:623)
do_softirq (kernel/softirq.c:523)
__local_bh_enable_ip (kernel/softirq.c:?)
__dev_queue_xmit (net/core/dev.c:?)
ip_finish_output2 (net/ipv4/ip_output.c:237)
ip_output (net/ipv4/ip_output.c:438)
__ip_queue_xmit (net/ipv4/ip_output.c:534)
__tcp_transmit_skb (net/ipv4/tcp_output.c:1693)
tcp_write_xmit (net/ipv4/tcp_output.c:3064)
tcp_sendmsg_locked (net/ipv4/tcp.c:?)
tcp_sendmsg (net/ipv4/tcp.c:1465)
inet_sendmsg (net/ipv4/af_inet.c:865)
sock_write_iter (net/socket.c:1195)
vfs_write (fs/read_write.c:688)
...
Uninit was created at:
kmem_cache_alloc_noprof (mm/slub.c:4873)
sk_prot_alloc (net/core/sock.c:2239)
sk_alloc (net/core/sock.c:2301)
inet_create (net/ipv4/af_inet.c:334)
__sock_create (net/socket.c:1605)
__sys_socket (net/socket.c:1747)
Fix this at the root by adding sk_rx_queue_clear() alongside
sk_tx_queue_clear() in sk_clone().
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260407084219.95718-1-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Most ndo_start_xmit() methods expects headers of gso packets
to be already in skb->head.
net/core/tso.c users are particularly at risk, because tso_build_hdr()
does a memcpy(hdr, skb->data, hdr_len);
qdisc_pkt_len_segs_init() already does a dissection of gso packets.
Use pskb_may_pull() instead of skb_header_pointer() to make
sure drivers do not have to reimplement this.
Some malicious packets could be fed, detect them so that we can
drop them sooner with a new SKB_DROP_REASON_SKB_BAD_GSO drop_reason.
Fixes: e876f208af ("net: Add a software TSO helper API")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260403221540.3297753-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reduce indentation level by returning early if the transport header
was not set.
Add an unlikely() clause as this is not the common case.
No functional change.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260403221540.3297753-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Sashiko points out that we use qops in __net_mp_open_rxq()
but never validate they are null. This was introduced when
check was moved from netdev_rx_queue_restart().
Look at ops directly instead of the locking config.
qops imply netdev_need_ops_lock(). We used netdev_need_ops_lock()
initially to signify that the real_num_rx_queues check below
is safe without rtnl_lock, but I'm not sure if this is actually
clear to most people, anyway.
Fixes: da7772a2b4 ("net: move mp->rx_page_size validation to __net_mp_open_rxq()")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Mina Almasry <almasrymina@google.com>
Link: https://patch.msgid.link/20260404001938.2425670-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SKB_SMALL_HEAD_CACHE_SIZE is intentionally set to a non-power-of-2
value (e.g. 704 on x86_64) to avoid collisions with generic kmalloc
bucket sizes. This ensures that skb_kfree_head() can reliably use
skb_end_offset to distinguish skb heads allocated from
skb_small_head_cache vs. generic kmalloc caches.
However, when KFENCE is enabled, kfence_ksize() returns the exact
requested allocation size instead of the slab bucket size. If a caller
(e.g. bpf_test_init) allocates skb head data via kzalloc() and the
requested size happens to equal SKB_SMALL_HEAD_CACHE_SIZE, then
slab_build_skb() -> ksize() returns that exact value. After subtracting
skb_shared_info overhead, skb_end_offset ends up matching
SKB_SMALL_HEAD_HEADROOM, causing skb_kfree_head() to incorrectly free
the object to skb_small_head_cache instead of back to the original
kmalloc cache, resulting in a slab cross-cache free:
kmem_cache_free(skbuff_small_head): Wrong slab cache. Expected
skbuff_small_head but got kmalloc-1k
Fix this by always calling kfree(head) in skb_kfree_head(). This keeps
the free path generic and avoids allocator-specific misclassification
for KFENCE objects.
Fixes: bf9f1baa27 ("net: add dedicated kmem_cache for typical/small skb->head")
Reported-by: Antonius <antonius@bluedragonsec.com>
Closes: https://lore.kernel.org/netdev/CAK8a0jxC5L5N7hq-DT2_NhUyjBxrPocoiDazzsBk4TGgT1r4-A@mail.gmail.com/
Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260403014517.142550-1-jiayuan.chen@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When net.core.skb_defer_max is adjusted to zero, napi_consume_skb()
shouldn't go into that deeper in skb_attempt_defer_free() because it adds
an additional pair of local_bh_enable/disable() which is evidently not
needed. Advancing the check of the static key saves more cycles and
benefits non defer case.
Signed-off-by: Jason Xing <kernelxing@tencent.com>
Link: https://patch.msgid.link/20260402034114.65766-1-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
rtnl_newlink() lacks a CAP_NET_ADMIN capability check on the peer
network namespace when creating paired devices (veth, vxcan,
netkit). This allows an unprivileged user with a user namespace
to create interfaces in arbitrary network namespaces, including
init_net.
Add a netlink_ns_capable() check for CAP_NET_ADMIN in the peer
namespace before allowing device creation to proceed.
Fixes: 81adee47df ("net: Support specifying the network namespace upon device creation.")
Signed-off-by: Nikolaos Gkarlis <nickgarlis@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260402181432.4126920-1-nickgarlis@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Pull bpf fixes from Alexei Starovoitov:
- Fix register equivalence for pointers to packet (Alexei Starovoitov)
- Fix incorrect pruning due to atomic fetch precision tracking (Daniel
Borkmann)
- Fix grace period wait for bpf_link-ed tracepoints (Kumar Kartikeya
Dwivedi)
- Fix use-after-free of sockmap's sk->sk_socket (Kuniyuki Iwashima)
- Reject direct access to nullable PTR_TO_BUF pointers (Qi Tang)
- Reject sleepable kprobe_multi programs at attach time (Varun R
Mallya)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Add more precision tracking tests for atomics
bpf: Fix incorrect pruning due to atomic fetch precision tracking
bpf: Reject sleepable kprobe_multi programs at attach time
bpf: reject direct access to nullable PTR_TO_BUF pointers
bpf: sockmap: Fix use-after-free of sk->sk_socket in sk_psock_verdict_data_ready().
bpf: Fix grace period wait for tracepoint bpf_link
bpf: Fix regsafe() for pointers to packet
Commit ba9db6f907 ("net: clear the dst when changing skb protocol")
added dst clearing when a BPF program changes the skb protocol
(e.g. IPv4 to IPv6). Since that was a fix we only cleared the dst when
the L3 protocol actually changes to keep it minimal. As suggested during
the discussion (see Link) encap or decap operation which wraps or unwraps
a same-protocol header may also render the existing dst incorrect - even
if that doesn't result in a crash, just the wrong route for the now-outermost
IP dst.
Make dropping dst unconditional for bpf_skb_change_proto() and all
L3 encap / decap ops.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/CANP3RGfRaYwve_xgxH6Tp2zenzKn2-DjZ9tg023WVzfdJF3p_w@mail.gmail.com
Link: https://patch.msgid.link/20260329180428.2657785-1-kuba@kernel.org
As IPv6 is built-in only, the ipv6_bpf_stub can be removed completely.
Convert all ipv6_bpf_stub usage to direct function calls instead. The
fallback functions introduced previously will prevent linkage errors
when CONFIG_IPV6 is disabled.
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Tested-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260325120928.15848-10-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As IPv6 is built-in only, it does not make sense to continue using
IS_BUILTIN(CONFIG_IPV6). Therefore, replace it with IS_ENABLED() when
necessary and drop it if it isn't valid anymore.
Notice that there is still one instance related to ICMPv6, as it
requires more changes it will be handle separately.
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Tested-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20260325120928.15848-4-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
As IPv6 is built-in only, the macro is always evaluating to an empty
one. Remove it completely from the code.
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20260325120928.15848-3-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Commit 6b57ff21a3 ("rtnetlink: Protect link_ops by mutex.") swapped
the EEXIST check with the init_srcu_struct, but didn't add cleanup of
the SRCU struct we just allocated in case of error.
Fixes: 6b57ff21a3 ("rtnetlink: Protect link_ops by mutex.")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/e77fe499f9a58c547b33b5212b3596dad417cec6.1774025341.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
NETIF_F_IPV6_CSUM only advertises support for checksum offload of
packets without IPv6 extension headers. Packets with extension
headers must fall back onto software checksumming. Since TSO
depends on checksum offload, those must revert to GSO.
The below commit introduces that fallback. It always checks
network header length. For tunneled packets, the inner header length
must be checked instead. Extend the check accordingly.
A special case is tunneled packets without inner IP protocol. Such as
RFC 6951 SCTP in UDP. Those are not standard IPv6 followed by
transport header either, so also must revert to the software GSO path.
Cc: stable@vger.kernel.org
Fixes: 864e339697 ("net: gso: Forbid IPv6 TSO with extensions on devices with only IPV6_CSUM")
Reported-by: Tangxin Xie <xietangxin@yeah.net>
Closes: https://lore.kernel.org/netdev/0414e7e2-9a1c-4d7c-a99d-b9039cf68f40@yeah.net/
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260320190148.2409107-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Switch the function to use the proper sysfs_emit("%pb").
Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Yury Norov <ynorov@nvidia.com>
Link: https://patch.msgid.link/20260319201713.941956-3-ynorov@nvidia.com
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
rtnl_link_get_slave_info_data_size counts IFLA_INFO_SLAVE_DATA, but
rtnl_link_slave_info_fill adds both IFLA_INFO_SLAVE_DATA and
IFLA_INFO_SLAVE_KIND.
Fixes: ba7d49b1f0 ("rtnetlink: provide api for getting and setting slave info")
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/049843b532e23cde7ddba263c0bbe35ba6f0d26d.1773919462.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add drop reasons to __dev_queue_xmit():
- SKB_DROP_REASON_DEV_READY : device is not UP.
- SKB_DROP_REASON_RECURSION_LIMIT : recursion limit on virtual device is hit.
Also add an unlikely() for the SKB_DROP_REASON_DEV_READY case,
and reduce indentation level.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260312201824.203093-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since UDP and UDP-Lite had dedicated socket hash tables for
each, we have had to pass the pointer down to many socket
lookup functions.
UDP-Lite gone, and we do not need to do that.
Let's fetch net->ipv4.udp_table only where needed in IPv4
stack: __udp4_lib_lookup(), __udp4_lib_mcast_deliver(),
and udp_diag_dump().
Some functions are renamed as the wrapper functions are no
longer needed.
__udp4_lib_err() -> udp_err()
__udp_diag_destroy() -> udp_diag_destroy()
udp_dump_one() -> udp_diag_dump_one()
udp_dump() -> udp_diag_dump()
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-15-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Since UDP and UDP-Lite had dedicated socket hash tables for
each, we have had to pass the pointer down to many socket
lookup functions.
UDP-Lite gone, and we do not need to do that.
Let's fetch net->ipv4.udp_table only where needed in IPv6
stack: __udp6_lib_lookup() and __udp6_lib_mcast_deliver().
__udp6_lib_err() is renamed to udpv6_err() as its wrapper
is no longer needed.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-14-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add a static key to bypass skb_attempt_defer_free() steps
if net.core.skb_defer_max is set to zero.
Main benefit is the atomic_long_inc_return() avoidance.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260311191340.1996888-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Majority of tcp_release_cb() calls do nothing at all.
Provide tcp_release_cb_cond() helper so that release_sock()
can avoid these calls.
Also hint the compiler that __release_sock() and wake_up()
are rarely called.
$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-77 (-77)
Function old new delta
release_sock 258 181 -77
Total: Before=25235790, After=25235713, chg -0.00%
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260310124451.2280968-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Prior to commit dc2a27e524 ("neighbour: Update pneigh_entry in
pneigh_create()."), a pneigh's protocol was updated only when the
value of the NDA_PROTOCOL attribute was non-0. While moving the code,
that check was removed. This is a small change of user-visible
behavior, and inconsistent with the (non-proxy) neighbour behavior.
Fixes: dc2a27e524 ("neighbour: Update pneigh_entry in pneigh_create().")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/38c61de1bb032871a886aff9b9b52fe1cdd4cada.1772894876.git.sd@queasysnail.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called which
initializes it. If bpf_redirect_neigh() is called with explicit AF_INET6
nexthop parameters, __bpf_redirect_neigh_v6() can skip the IPv6 FIB lookup
and call bpf_out_neigh_v6() directly. bpf_out_neigh_v6() then calls
ip_neigh_gw6(), which uses ipv6_stub->nd_tbl.
BUG: kernel NULL pointer dereference, address: 0000000000000248
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:skb_do_redirect+0x44f/0xf40
Call Trace:
<TASK>
? srso_alias_return_thunk+0x5/0xfbef5
? __tcf_classify.constprop.0+0x83/0x160
? srso_alias_return_thunk+0x5/0xfbef5
? tcf_classify+0x2b/0x50
? srso_alias_return_thunk+0x5/0xfbef5
? tc_run+0xb8/0x120
? srso_alias_return_thunk+0x5/0xfbef5
__dev_queue_xmit+0x6fa/0x1000
? srso_alias_return_thunk+0x5/0xfbef5
packet_sendmsg+0x10da/0x1700
? srso_alias_return_thunk+0x5/0xfbef5
__sys_sendto+0x1f3/0x220
__x64_sys_sendto+0x24/0x30
do_syscall_64+0x101/0xf80
? exc_page_fault+0x6e/0x170
? srso_alias_return_thunk+0x5/0xfbef5
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Fix this by adding an early check in bpf_out_neigh_v6(). If IPv6 is
disabled, drop the packet before neighbor lookup.
Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de>
Fixes: ba452c9e99 ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop")
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-4-e2677e85628c@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When booting with the 'ipv6.disable=1' parameter, the nd_tbl is never
initialized because inet6_init() exits before ndisc_init() is called which
initializes it. If bpf_redirect_neigh() is called from tc with an explicit
nexthop of nh_family == AF_INET6, bpf_out_neigh_v4() takes the AF_INET6
branch and calls ip_neigh_gw6(), which relies on ipv6_stub->nd_tbl.
BUG: kernel NULL pointer dereference, address: 0000000000000248
Oops: Oops: 0000 [#1] SMP NOPTI
RIP: 0010:skb_do_redirect+0xb93/0xf00
Call Trace:
<TASK>
? srso_alias_return_thunk+0x5/0xfbef5
? __tcf_classify.constprop.0+0x83/0x160
? srso_alias_return_thunk+0x5/0xfbef5
? tcf_classify+0x2b/0x50
? srso_alias_return_thunk+0x5/0xfbef5
? tc_run+0xb8/0x120
? srso_alias_return_thunk+0x5/0xfbef5
__dev_queue_xmit+0x6fa/0x1000
? srso_alias_return_thunk+0x5/0xfbef5
? srso_alias_return_thunk+0x5/0xfbef5
? alloc_skb_with_frags+0x58/0x200
packet_sendmsg+0x10da/0x1700
? srso_alias_return_thunk+0x5/0xfbef5
__sys_sendto+0x1f3/0x220
__x64_sys_sendto+0x24/0x30
do_syscall_64+0x101/0xf80
? exc_page_fault+0x6e/0x170
? srso_alias_return_thunk+0x5/0xfbef5
entry_SYSCALL_64_after_hwframe+0x77/0x7f
</TASK>
Fix this by adding an early check in the AF_INET6 branch of
bpf_out_neigh_v4(). If IPv6 is disabled, unlock RCU and drop the packet.
Suggested-by: Fernando Fernandez Mancera <fmancera@suse.de>
Fixes: ba452c9e99 ("bpf: Fix bpf_redirect_neigh helper api to support supplying nexthop")
Signed-off-by: Ricardo B. Marlière <rbm@suse.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://patch.msgid.link/20260307-net-nd_tbl_fixes-v4-3-e2677e85628c@suse.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
While testing other changes in vng I noticed that
nl_netdev.page_pool_check flakes. This never happens in real CI.
Turns out vng may boot and get to that test in less than a second.
page_pool_detached() records the detach time in seconds, so if
vng is fast enough detach time is set to 0. Other code treats
0 as "not detached". detach_time is only used to report the state
to the user, so it's not a huge deal in practice but let's fix it.
Store the raw ktime_t (nanoseconds) instead. A nanosecond value
of 0 is practically impossible.
Acked-by: Jesper Dangaard Brouer <hawk@kernel.org>
Fixes: 69cb4952b6 ("net: page_pool: report when page pool was destroyed")
Link: https://patch.msgid.link/20260310003907.3540019-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
dev_open() already is exported, but drivers which use the netdev
instance lock need to use netif_open() instead. netif_close() is
also already exported [1] so this completes the pairing.
This export is required for the following fbnic self tests to
avoid calling ndo_stop() and ndo_open() in favor of the
more appropriate netif_open() and netif_close() that notifies
any listeners that the interface went down to test and is now
coming back up.
Link: https://patch.msgid.link/20250309215851.2003708-1-sdf@fomichev.me [1]
Signed-off-by: Mike Marciniszyn (Meta) <mike.marciniszyn@gmail.com>
Link: https://patch.msgid.link/20260307105847.1438-2-mike.marciniszyn@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Tunnel xmit functions (iptunnel_xmit, ip6tunnel_xmit) lack their own
recursion limit. When a bond device in broadcast mode has GRE tap
interfaces as slaves, and those GRE tunnels route back through the
bond, multicast/broadcast traffic triggers infinite recursion between
bond_xmit_broadcast() and ip_tunnel_xmit()/ip6_tnl_xmit(), causing
kernel stack overflow.
The existing XMIT_RECURSION_LIMIT (8) in the no-qdisc path is not
sufficient because tunnel recursion involves route lookups and full IP
output, consuming much more stack per level. Use a lower limit of 4
(IP_TUNNEL_RECURSION_LIMIT) to prevent overflow.
Add recursion detection using dev_xmit_recursion helpers directly in
iptunnel_xmit() and ip6tunnel_xmit() to cover all IPv4/IPv6 tunnel
paths including UDP encapsulated tunnels (VXLAN, Geneve, etc.).
Move dev_xmit_recursion helpers from net/core/dev.h to public header
include/linux/netdevice.h so they can be used by tunnel code.
BUG: KASAN: stack-out-of-bounds in blake2s.constprop.0+0xe7/0x160
Write of size 32 at addr ffff88810033fed0 by task kworker/0:1/11
Workqueue: mld mld_ifc_work
Call Trace:
<TASK>
__build_flow_key.constprop.0 (net/ipv4/route.c:515)
ip_rt_update_pmtu (net/ipv4/route.c:1073)
iptunnel_xmit (net/ipv4/ip_tunnel_core.c:84)
ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847)
gre_tap_xmit (net/ipv4/ip_gre.c:779)
dev_hard_start_xmit (net/core/dev.c:3887)
sch_direct_xmit (net/sched/sch_generic.c:347)
__dev_queue_xmit (net/core/dev.c:4802)
bond_dev_queue_xmit (drivers/net/bonding/bond_main.c:312)
bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5279)
bond_start_xmit (drivers/net/bonding/bond_main.c:5530)
dev_hard_start_xmit (net/core/dev.c:3887)
__dev_queue_xmit (net/core/dev.c:4841)
ip_finish_output2 (net/ipv4/ip_output.c:237)
ip_output (net/ipv4/ip_output.c:438)
iptunnel_xmit (net/ipv4/ip_tunnel_core.c:86)
gre_tap_xmit (net/ipv4/ip_gre.c:779)
dev_hard_start_xmit (net/core/dev.c:3887)
sch_direct_xmit (net/sched/sch_generic.c:347)
__dev_queue_xmit (net/core/dev.c:4802)
bond_dev_queue_xmit (drivers/net/bonding/bond_main.c:312)
bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5279)
bond_start_xmit (drivers/net/bonding/bond_main.c:5530)
dev_hard_start_xmit (net/core/dev.c:3887)
__dev_queue_xmit (net/core/dev.c:4841)
ip_finish_output2 (net/ipv4/ip_output.c:237)
ip_output (net/ipv4/ip_output.c:438)
iptunnel_xmit (net/ipv4/ip_tunnel_core.c:86)
ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847)
gre_tap_xmit (net/ipv4/ip_gre.c:779)
dev_hard_start_xmit (net/core/dev.c:3887)
sch_direct_xmit (net/sched/sch_generic.c:347)
__dev_queue_xmit (net/core/dev.c:4802)
bond_dev_queue_xmit (drivers/net/bonding/bond_main.c:312)
bond_xmit_broadcast (drivers/net/bonding/bond_main.c:5279)
bond_start_xmit (drivers/net/bonding/bond_main.c:5530)
dev_hard_start_xmit (net/core/dev.c:3887)
__dev_queue_xmit (net/core/dev.c:4841)
mld_sendpack
mld_ifc_work
process_one_work
worker_thread
</TASK>
Fixes: 745e20f1b6 ("net: add a recursion limit in xmit path")
Reported-by: Xiang Mei <xmei5@asu.edu>
Signed-off-by: Weiming Shi <bestswngs@gmail.com>
Link: https://patch.msgid.link/20260306160133.3852900-2-bestswngs@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Following typical script is extremely disruptive,
because each graft operation calls dev_deactivate()
which resets all the queues of the device.
QPARAM="limit 100000 flow_limit 1000 buckets 4096"
TXQS=64
for ETH in eth1
do
tc qd del dev $ETH root 2>/dev/null
tc qd add dev $ETH root handle 1: mq
for i in `seq 1 $TXQS`
do
slot=$( printf %x $(( i )) )
tc qd add dev $ETH parent 1:$slot fq $QPARAM
done
done
One can add "ip link set dev $ETH down/up" to reduce the disruption time:
QPARAM="limit 100000 flow_limit 1000 buckets 4096"
TXQS=64
for ETH in eth1
do
ip link set dev $ETH down
tc qd del dev $ETH root 2>/dev/null
tc qd add dev $ETH root handle 1: mq
for i in `seq 1 $TXQS`
do
slot=$( printf %x $(( i )) )
tc qd add dev $ETH parent 1:$slot fq $QPARAM
done
ip link set dev $ETH up
done
Or we can add a @reset_needed flag to dev_deactivate() and
dev_deactivate_many().
This flag is set to true at device dismantle or linkwatch_do_dev(),
and to false for graft operations.
In the future, we might only stop one queue instead of the whole
device, ie call dev_deactivate_queue() instead of dev_deactivate().
I think the problem (quadratic behavior) was added in commit
2fb541c862 ("net: sch_generic: aviod concurrent reset and enqueue op
for lockless qdisc") but this does not look serious enough to deserve
risky backports.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yunsheng Lin <linyunsheng@huawei.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Reviewed-by: Victor Nogueira <victor@mojatatu.com>
Link: https://patch.msgid.link/20260307163430.470644-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add SPDX-License-Identifier lines to several source
files under the network sub-directory. Work on files
in the core, dns_resolver, ipv4, ipv6 and
netfilter sub-dirs. Remove boilerplate
and license reference text to avoid ambiguity.
Rusty Russell has expressed that his contributions
were intended to be GPL-2.0-or-later.
Signed-off-by: Tim Bird <tim.bird@sony.com>
Link: https://patch.msgid.link/20260305004724.87469-1-tim.bird@sony.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR (net-7.0-rc3).
No conflicts.
Adjacent changes:
net/netfilter/nft_set_rbtree.c
fb7fb40163 ("netfilter: nf_tables: clone set on flush only")
3aea466a43 ("netfilter: nft_set_rbtree: don't disable bh when acquiring tree lock")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The current formula for calculating XDP tailroom in mbuf packets works only
if each frag has its own page (if rxq->frag_size is PAGE_SIZE), this
defeats the purpose of the parameter overall and without any indication
leads to negative calculated tailroom on at least half of frags, if shared
pages are used.
There are not many drivers that set rxq->frag_size. Among them:
* i40e and enetc always split page uniformly between frags, use shared
pages
* ice uses page_pool frags via libeth, those are power-of-2 and uniformly
distributed across page
* idpf has variable frag_size with XDP on, so current API is not applicable
* mlx5, mtk and mvneta use PAGE_SIZE or 0 as frag_size for page_pool
As for AF_XDP ZC, only ice, i40e and idpf declare frag_size for it. Modulo
operation yields good results for aligned chunks, they are all power-of-2,
between 2K and PAGE_SIZE. Formula without modulo fails when chunk_size is
2K. Buffers in unaligned mode are not distributed uniformly, so modulo
operation would not work.
To accommodate unaligned buffers, we could define frag_size as
data + tailroom, and hence do not subtract offset when calculating
tailroom, but this would necessitate more changes in the drivers.
Define rxq->frag_size as an even portion of a page that fully belongs to a
single frag. When calculating tailroom, locate the data start within such
portion by performing a modulo operation on page offset.
Fixes: bf25146a55 ("bpf: add frags support to the bpf_xdp_adjust_tail() API")
Acked-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Larysa Zaremba <larysa.zaremba@intel.com>
Link: https://patch.msgid.link/20260305111253.2317394-2-larysa.zaremba@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
