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853 commits

Author SHA1 Message Date
Shardul Bankar
9e95b1a94c udp: remove a disconnected socket from the 4-tuple hash table
A UDP socket bound to a specific address and port keeps its entry in the
4-tuple hash table after it is disconnected:

    sk binds to 127.0.0.1:21001
    sk connects to 127.0.0.2:20001	// filed in the 4-tuple table
    sk disconnects, connect(AF_UNSPEC)	// still filed, peer now 0.0.0.0:0

__udp_disconnect() takes a socket out of that table only as a side effect
of ->rehash() or ->unhash(), and it skips ->rehash() when
SOCK_BINDADDR_LOCK is set and ->unhash() when SOCK_BINDPORT_LOCK is set.
commit 6996a2d2d0 ("udp: Unhash auto-bound connected sk from 4-tuple hash
table when disconnected.") fixed the same end state for a wildcard-bound
socket, by a path this one does not take.

The entry is counted whether or not anything hits it. hash4_cnt on the
hash2 slot stays raised for as long as the socket lives, so udp_has_hash4()
keeps sending every packet for that address and port through the 4-tuple
lookup first.

On IPv6 it can also be hit. __udp_disconnect() does not clear sk_v6_daddr,
so udp_v6_rehash() files the entry under the peer the socket was connected
to with a zero dport, and inet6_match() compares that same
field: a datagram from the former peer with a zero source port matches,
and source port zero is accepted on receive. On IPv4 the peer is cleared,
so a match would need a zero source address as well, which the routing
layer rejects as martian. The stale sk_v6_daddr is a separate defect, not
addressed here; removing the entry closes this path either way.

The entry can also be relocated. __udp_disconnect() clears sk_bound_dev_if,
so a subsequent SO_BINDTODEVICE calls ->rehash(), and because the receive
address is still specific udp_lib_rehash() moves the entry instead of
removing it, into the bucket that (rcv_saddr, num, 0, 0) hashes to -- a
pure function of the address and port, so every socket reaching this state
on one address and port collects in one bucket. The bucket cannot be chosen
from outside, as udp_ehashfn() is seeded with a per-boot secret. This last
one became reachable only with commit 644f9108f3 ("udp: Make rehash4
independent in udp_lib_rehash()"), which moved the hash4 handling out of a
branch a disconnected socket does not take; the stale entry itself dates
from the commit in Fixes.

Take the socket out of the table before __udp_disconnect() runs, while it
still matches how it was filed. This also reaches the wildcard case ahead
of udp_lib_rehash()'s udp_unhash4() branch, leaving that branch unreachable
from udp_disconnect(); removing it belongs in net-next. udp_disconnect()
and udp_abort() are the only UDP entries into __udp_disconnect(), which is
shared with raw, ping and l2tp sockets that are not struct udp_sock:
ping_prot.obj_size is sizeof(struct inet_sock), so udp_hashed4() on one
would read past the allocation.

Fixes: 78c91ae2c6 ("ipv4/udp: Add 4-tuple hash for connected socket")
Assisted-by: LLM
Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260917-udp_hash4_fix_v1-v1-2-718891af0d7a@mpiricsoftware.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-09-22 10:57:53 +02:00
Shardul Bankar
5fd0783b99 udp: relocate a connected socket in the 4-tuple hash table on re-connect
A connected UDP socket that connects again to a different peer is not
re-filed in the 4-tuple hash table:

    sk binds to 127.0.0.1:21001
    sk connects to 127.0.0.2:20001	// filed under hash(sk, peer1)
    sk connects to 127.0.0.3:20002	// still filed under hash(sk, peer1)
    packet from 127.0.0.3:20002		// hash(sk, peer2) misses, so the
					// lookup falls back to scoring the
					// hash2 chain for this address
					// and port

udp_lib_hash4() returns early when the socket is already hashed, assuming
->rehash() relocates it. ->rehash() runs from __ip{4,6}_datagram_connect()
only while the receive address is unset, which a second connect never is:
the first connect assigns it, whether the socket was bound to a specific
address or to the wildcard. commit 644f9108f3 ("udp: Make rehash4
independent in udp_lib_rehash()") added that early return and named
connect(AF_UNSPEC) as the way around it. That workaround does not help a
socket with both SOCK_BINDADDR_LOCK and SOCK_BINDPORT_LOCK set, because
__udp_disconnect() skips ->rehash() for the first and ->unhash() for the
second.

Delivery is correct either way.

Relocate the socket when the hash it is filed under differs from the one
requested, which is what commit 78c91ae2c6 ("ipv4/udp: Add 4-tuple hash
for connected socket") did before the early return became unconditional. It
is done here under hslot->lock, which that version did not take, to match
udp_lib_rehash() and udp_lib_unhash(). hslot2 is unchanged, so hash4_cnt
needs no adjustment, as in udp_lib_rehash(). A first connect is unaffected,
and IPv6 shares the code.

With 500 sockets on the port, a re-connected socket measured 522,553 pps
without this change and 2,055,078 with it. The UDP side was noted as
remaining work in [1].

Link: https://lore.kernel.org/netdev/apnHqmYZQ4yzOP4N@v4bel/ [1]
Fixes: 644f9108f3 ("udp: Make rehash4 independent in udp_lib_rehash()")
Assisted-by: LLM
Signed-off-by: Shardul Bankar <shardul.b@mpiricsoftware.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260917-udp_hash4_fix_v1-v1-1-718891af0d7a@mpiricsoftware.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-09-22 10:57:53 +02:00
Ido Schimmel
4c3499f79f ipv4: udp: Create exceptions before socket matching
Currently, when ICMP Fragmentation Needed and Redirect Message packets
are locally delivered and quote a UDP packet, a FIB nexthop exception
(FNHE) is only created if the kernel can match the UDP packet to an
existing socket.

This behavior allows off-path attackers to conduct a side-channel attack
on the FNHE cache in order to discover the ephemeral port used by a
connected UDP socket.

Commit 6457378fe7 ("ipv4: use siphash instead of Jenkins in
fnhe_hashfun()") and commit 67d6d681e1 ("ipv4: make exception cache
less predictible") tried to mitigate such attacks by making it harder
for attackers to discover hash collisions in the FNHE cache and by
randomizing the number of exceptions a hash bucket can hold,
respectively. Unfortunately, both of the mitigations can be bypassed.

Instead, mitigate such attacks by always creating a FNHE, even before
trying to find a matching socket. Do that by calling ipv4_update_pmtu()
and ipv4_redirect(), the helpers used when the quoted packet did not
originate from a socket.

This means that guesses (right or wrong) from an off-path attacker will
always result in a FNHE being created or updated in the cache that the
attacker can observe.

Pass an oif of 0, in a similar fashion to icmp_err(). This is also the
oif used by the socket path for sockets that are not bound to a device.

Note that this does not allow attackers to create FNHEs that they could
not create before, as both helpers can already be reached with little to
no validation. For example, by sending an ICMP error that quotes an ICMP
Echo Reply or one that quotes a UDP source port that matches a wildcard
socket.

Also note that in the good case (matched socket) the above scheme comes
at the cost of an extra route lookup, as the no socket helpers perform
their own lookup before the one performed by ipv4_sk_update_pmtu() /
ipv4_sk_redirect(). When the two resolve to different nexthops, it also
results in two exceptions being created for the same destination IP. One
in the FNHE cache of the nexthop resolved by the no socket helpers and
another in the FNHE cache of the nexthop used by the socket.

Fixes: 4895c771c7 ("ipv4: Add FIB nexthop exceptions.")
Cc: stable@vger.kernel.org
Reported-by: Amit Klein <aksecurity@gmail.com>
Reported-by: Noam Caspi <noam.caspi@mail.huji.ac.il>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20260828192344.2596928-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-31 19:56:30 -07:00
Xuanqiang Luo
ac08d183da raw: annotate disconnect-side IPv4 match writers
raw_v4_match() reads inet_daddr, inet_rcv_saddr and
sk_bound_dev_if locklessly under RCU. Bind and connect writers are
annotated, but __udp_disconnect() still clears the same fields using
plain stores.

Commit 18f116931f ("raw: annotate lockless match fields in
raw_v4_match()") added the lockless readers and annotated the raw bind
and datagram connect writers. Its v4 revision intentionally left the
shared disconnect-side IPv4 writers for follow-up cleanup.

Complete that follow-up by using WRITE_ONCE() for the disconnect-side
stores, including the inet_rcv_saddr reset in inet_reset_saddr(), to
pair with the lockless raw socket matcher.

Fixes: 0daf07e527 ("raw: convert raw sockets to RCU")
Link: https://lore.kernel.org/netdev/20260716142958.3064224-1-runyu.xiao@seu.edu.cn/
Suggested-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Xuanqiang Luo <luoxuanqiang@kylinos.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260828012918.1461-1-xuanqiang.luo@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-08-30 14:14:57 -07:00
Paolo Abeni
4d3365d5d3 Merge branch 'big-tcp-for-udp-tunnels'
Alice Mikityanska says:

====================
BIG TCP for UDP tunnels

This series is a follow-up to "BIG TCP without HBH in IPv6", and it adds
support for BIG TCP IPv4/IPv6 workloads in vxlan and geneve. Now that
IPv6 BIG TCP doesn't require stripping the HBH in all various
combinations in tunneled traffic, adding BIG TCP becomes feasible.

Patch 01 adds accessors for the length field in the UDP header, as
suggested by Paolo in review. The usage of udp_set_len is then added in
the following patches that start using length=0 in BIG TCP UDP packets.

Patches 02-04 close the gaps that prevent BIG TCP packets from going
through UDP tunnel code.

Patch 05 validates packets in udp_gro_receive to exclude packets with
length=0 from GRO aggregation.

Patch 06 is for proper formatting in tcpdump (set UDP len to 0 rather
than a trimmed value on overflow).

Patches 07-08 bump up tso_max_size for VXLAN and GENEVE.

Patch 09 adds selftests.
====================$

Link: https://patch.msgid.link/20260710134242.216538-1-alice.kernel@fastmail.im
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-22 13:49:03 +02:00
Alice Mikityanska
efbc1aa8ed udp: Support gro_ipv4_max_size > 65536
Currently, gro_max_size and gro_ipv4_max_size can be set to values
bigger than 65536, and GRO will happily aggregate UDP to the configured
size (for example, with TCP traffic in VXLAN tunnels). However,
udp_gro_complete uses the 16-bit length field in the UDP header to store
the length of the aggregated packet. It leads to the packet truncation
later in udp_rcv.

Fix this by storing 0 to the UDP length field and by restoring the real
length from skb->len in udp_rcv. IP GRO already can store 0 to the IP
length field, and iph_totlen()/ipv6_payload_len() are capable of
restoring the real length, because the relevant packets (BIG TCP
tunneled in UDP tunnels) will have skb_is_gso_tcp == true.

Additionally, restrict handling uh->len=0 in udpv6_rcv to BIG TCP and
jumbograms only by using the udp_get_len helper.

Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260710134242.216538-5-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-22 13:47:02 +02:00
Alice Mikityanska
5329647dad net: Use helpers to get/set UDP len tree-wide
Since BIG TCP for UDP tunnels will start using len=0 in the UDP header
as an indicator of a GSO packet bigger than 65535 bytes, this commit
introduces the following getter and setters to use tree-wide, in order
to explicitly mark places where len=0 may be expected, and handle them
properly:

1. udp_set_len() sets uh->len to its real value if it's not bigger than
65535, and to 0 otherwise: to be used in GSO context with aggregated
packets.

2. udp_set_len_short() is to be used when the length is known to fit 16
bits. It WARNs when the caller tries to assign a bigger value if
CONFIG_DEBUG_NET=y.

3. udp_get_len_short() returns len in host byte order: to be used on the
RX side to deal with non-aggregated packets, or to access the raw value
of the len field.

4. udp_get_len() decodes uh->len set by udp_set_len(). It checks whether
the packet is GSO to guard from malformed packets.

At the moment udp_set_len() is not used, a following commit will start
using it after enabling len>65535 for GSO.

Raw uh->len (in network byte order) is still accessed in a few places
for checksum calculation purposes, and to decode len=0 in udpv6_rcv for
jumbograms. udp_rcv and udpv6_rcv will be addressed by the commit that
starts using udp_set_len() to set UDP len=0 for BIG TCP packets in UDP
tunnels.

Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20260710134242.216538-2-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-22 13:47:02 +02:00
Anton Danilov
3cb8d4b9bf udp: fix encapsulation packet resubmit in multicast deliver
When a UDP encapsulation socket (e.g., FOU) receives a multicast
packet, __udp4_lib_mcast_deliver() and __udp6_lib_mcast_deliver()
call consume_skb() when udp_queue_rcv_skb() returns a positive value.
A positive return value from udp_queue_rcv_skb() indicates that the
encap_rcv handler (e.g., fou_udp_recv) has consumed the UDP header
and wants the packet to be resubmitted to the IP protocol handler
for further processing (e.g., as a GRE packet).

The unicast paths handle this correctly by propagating the return
value up to ip_protocol_deliver_rcu() / ip6_protocol_deliver_rcu()
for resubmission. However, the multicast paths destroy the packet
via consume_skb() instead of resubmitting it, causing silent packet
loss.

This affects any UDP encapsulation (FOU, GUE) combined with multicast
destination addresses.

Fix this by returning the value from udp_queue_rcv_skb() when it is
positive, matching the behavior of the corresponding unicast paths.
Note the sign difference between IPv4 and IPv6:

  - IPv4: udp_unicast_rcv_skb() returns -ret, and
    ip_protocol_deliver_rcu() resubmits when ret < 0
    (using -ret as the protocol number).
  - IPv6: udp6_unicast_rcv_skb() returns ret, and
    ip6_protocol_deliver_rcu() resubmits when ret > 0
    (using ret as the nexthdr).

Both mcast paths now follow the same convention as their respective
unicast paths.

Suggested-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Anton Danilov <littlesmilingcloud@gmail.com>
Assisted-by: Claude:claude-opus-4-6
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/5372ccac062193147e02b991d5328a5c3fa3a85a.1783372173.git.littlesmilingcloud@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-21 11:09:02 +02:00
Breno Leitao
f99d7065a4 udp: convert udp_lib_getsockopt to sockopt_t
In preparation for converting the proto-layer getsockopt callbacks to the
sockopt_t interface, switch udp_lib_getsockopt() to take a sockopt_t.

The thin udp_getsockopt()/udpv6_getsockopt() wrappers keep their __user
signature for now: they build a user-backed sockopt_t with
sockopt_init_user(), call the helper, and write the returned length back
to optlen. The helper uses copy_to_iter() instead of copy_to_user().
No functional change.

Signed-off-by: Breno Leitao <leitao@debian.org>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260630-getsockopt_phase2-v2-2-193335f3d4d1@debian.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2026-07-02 12:29:06 +02:00
Sechang Lim
3c94f241f7 udp: clear skb->dev before running a sockmap verdict
On the UDP receive path skb->dev is repurposed as dev_scratch (the
truesize/state cache set by udp_set_dev_scratch()), through the
union { struct net_device *dev; unsigned long dev_scratch; } in sk_buff.

When a UDP socket is in a sockmap, sk_data_ready is
sk_psock_verdict_data_ready(), which calls udp_read_skb() -> recv_actor()
(sk_psock_verdict_recv) to run the attached SK_SKB verdict program in softirq.
If that program calls a socket-lookup helper (bpf_sk_lookup_tcp/udp,
bpf_skc_lookup_tcp), bpf_skc_lookup() does:

	if (skb->dev)
		caller_net = dev_net(skb->dev);

skb->dev still holds the dev_scratch value (a non-NULL integer), so dev_net()
dereferences it as a struct net_device * and the kernel takes a general
protection fault on a non-canonical address in softirq:

  Oops: general protection fault, probably for non-canonical address 0x1010000800004a0
  CPU: 1 UID: 0 PID: 1406 Comm: syz.2.19 Not tainted 7.1.0-rc6 #1 PREEMPT(full)
  RIP: 0010:bpf_skc_lookup net/core/filter.c:7033 [inline]
  RIP: 0010:bpf_sk_lookup+0x45/0x160 net/core/filter.c:7047
  Call Trace:
   <IRQ>
   bpf_prog_4675cb904b7071f8+0x12e/0x14e
   bpf_prog_run_pin_on_cpu+0xc6/0x1f0
   sk_psock_verdict_recv+0x1ba/0x350
   udp_read_skb+0x31a/0x370
   sk_psock_verdict_data_ready+0x2e3/0x600
   __udp_enqueue_schedule_skb+0x4c8/0x650
   udpv6_queue_rcv_one_skb+0x3ec/0x740
   udp6_unicast_rcv_skb+0x11d/0x140
   ip6_protocol_deliver_rcu+0x61e/0x950
   ip6_input_finish+0xa9/0x150
   NF_HOOK+0x286/0x2f0
   ip6_input+0x117/0x220
   NF_HOOK+0x286/0x2f0
   __netif_receive_skb+0x85/0x200
   process_backlog+0x374/0x9a0
   __napi_poll+0x4f/0x1c0
   net_rx_action+0x3b0/0x770
   handle_softirqs+0x15a/0x460
   do_softirq+0x57/0x80
   </IRQ>

The rmem charge that dev_scratch accounted for is released by skb_recv_udp() on
dequeue, just above, so the scratch is dead by the time recv_actor() runs. Clear
skb->dev so bpf_skc_lookup() falls back to sock_net(skb->sk), which
skb_set_owner_sk_safe() set just above.

Fixes: 965b57b469 ("net: Introduce a new proto_ops ->read_skb()")
Cc: stable@vger.kernel.org
Signed-off-by: Sechang Lim <rhkrqnwk98@gmail.com>
Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260603162737.697215-1-rhkrqnwk98@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-06-04 09:01:51 -07:00
Linus Torvalds
91a4855d6c Networking changes for 7.1.
Core & protocols
 ----------------
 
  - Support HW queue leasing, allowing containers to be granted access
    to HW queues for zero-copy operations and AF_XDP.
 
  - Number of code moves to help the compiler with inlining.
    Avoid output arguments for returning drop reason where possible.
 
  - Rework drop handling within qdiscs to include more metadata
    about the reason and dropping qdisc in the tracepoints.
 
  - Remove the rtnl_lock use from IP Multicast Routing.
 
  - Pack size information into the Rx Flow Steering table pointer
    itself. This allows making the table itself a flat array of u32s,
    thus making the table allocation size a power of two.
 
  - Report TCP delayed ack timer information via socket diag.
 
  - Add ip_local_port_step_width sysctl to allow distributing the randomly
    selected ports more evenly throughout the allowed space.
 
  - Add support for per-route tunsrc in IPv6 segment routing.
 
  - Start work of switching sockopt handling to iov_iter.
 
  - Improve dynamic recvbuf sizing in MPTCP, limit burstiness and avoid
    buffer size drifting up.
 
  - Support MSG_EOR in MPTCP.
 
  - Add stp_mode attribute to the bridge driver for STP mode selection.
    This addresses concerns about call_usermodehelper() usage.
 
  - Remove UDP-Lite support (as announced in 2023).
 
  - Remove support for building IPv6 as a module.
    Remove the now unnecessary function calling indirection.
 
 Cross-tree stuff
 ----------------
 
  - Move Michael MIC code from generic crypto into wireless,
    it's considered insecure but some WiFi networks still need it.
 
 Netfilter
 ---------
 
  - Switch nft_fib_ipv6 module to no longer need temporary dst_entry
    object allocations by using fib6_lookup() + RCU.
    Florian W reports this gets us ~13% higher packet rate.
 
  - Convert IPVS's global __ip_vs_mutex to per-net service_mutex and
    switch the service tables to be per-net. Convert some code that
    walks the service lists to use RCU instead of the service_mutex.
 
  - Add more opinionated input validation to lower security exposure.
 
  - Make IPVS hash tables to be per-netns and resizable.
 
 Wireless
 --------
 
  - Finished assoc frame encryption/EPPKE/802.1X-over-auth.
 
  - Radar detection improvements.
 
  - Add 6 GHz incumbent signal detection APIs.
 
  - Multi-link support for FILS, probe response templates and
    client probing.
 
  - New APIs and mac80211 support for NAN (Neighbor Aware Networking,
    aka Wi-Fi Aware) so less work must be in firmware.
 
 Driver API
 ----------
 
  - Add numerical ID for devlink instances (to avoid having to create
    fake bus/device pairs just to have an ID). Support shared devlink
    instances which span multiple PFs.
 
  - Add standard counters for reporting pause storm events
    (implement in mlx5 and fbnic).
 
  - Add configuration API for completion writeback buffering
    (implement in mana).
 
  - Support driver-initiated change of RSS context sizes.
 
  - Support DPLL monitoring input frequency (implement in zl3073x).
 
  - Support per-port resources in devlink (implement in mlx5).
 
 Misc
 ----
 
  - Expand the YAML spec for Netfilter.
 
 Drivers
 -------
 
  - Software:
    - macvlan: support multicast rx for bridge ports with shared source
      MAC address
    - team: decouple receive and transmit enablement for IEEE 802.3ad
      LACP "independent control"
 
  - Ethernet high-speed NICs:
    - nVidia/Mellanox:
      - support high order pages in zero-copy mode (for payload
        coalescing)
      - support multiple packets in a page (for systems with 64kB pages)
    - Broadcom 25-400GE (bnxt):
      - implement XDP RSS hash metadata extraction
      - add software fallback for UDP GSO, lowering the IOMMU cost
    - Broadcom 800GE (bnge):
      - add link status and configuration handling
      - add various HW and SW statistics
    - Marvell/Cavium:
      - NPC HW block support for cn20k
    - Huawei (hinic3):
      - add mailbox / control queue
      - add rx VLAN offload
      - add driver info and link management
 
  - Ethernet NICs:
    - Marvell/Aquantia:
      - support reading SFP module info on some AQC100 cards
    - Realtek PCI (r8169):
      - add support for RTL8125cp
    - Realtek USB (r8152):
      - support for the RTL8157 5Gbit chip
      - add 2500baseT EEE status/configuration support
 
  - Ethernet NICs embedded and off-the-shelf IP:
    - Synopsys (stmmac):
      - cleanup and reorganize SerDes handling and PCS support
      - cleanup descriptor handling and per-platform data
      - cleanup and consolidate MDIO defines and handling
      - shrink driver memory use for internal structures
      - improve Tx IRQ coalescing
      - improve TCP segmentation handling
      - add support for Spacemit K3
    - Cadence (macb):
      - support PHYs that have inband autoneg disabled with GEM
      - support IEEE 802.3az EEE
      - rework usrio capabilities and handling
    - AMD (xgbe):
      - improve power management for S0i3
      - improve TX resilience for link-down handling
 
  - Virtual:
    - Google cloud vNIC:
      - support larger ring sizes in DQO-QPL mode
      - improve HW-GRO handling
      - support UDP GSO for DQO format
    - PCIe NTB:
      - support queue count configuration
 
  - Ethernet PHYs:
    - automatically disable PHY autonomous EEE if MAC is in charge
    - Broadcom:
      - add BCM84891/BCM84892 support
    - Micrel:
      - support for LAN9645X internal PHY
    - Realtek:
      - add RTL8224 pair order support
      - support PHY LEDs on RTL8211F-VD
      - support spread spectrum clocking (SSC)
    - Maxlinear:
      - add PHY-level statistics via ethtool
 
  - Ethernet switches:
    - Maxlinear (mxl862xx):
      - support for bridge offloading
      - support for VLANs
      - support driver statistics
 
  - Bluetooth:
    - large number of fixes and new device IDs
    - Mediatek:
      - support MT6639 (MT7927)
      - support MT7902 SDIO
 
  - WiFi:
    - Intel (iwlwifi):
      - UNII-9 and continuing UHR work
    - MediaTek (mt76):
      - mt7996/mt7925 MLO fixes/improvements
      - mt7996 NPU support (HW eth/wifi traffic offload)
    - Qualcomm (ath12k):
      - monitor mode support on IPQ5332
      - basic hwmon temperature reporting
      - support IPQ5424
    - Realtek:
      - add USB RX aggregation to improve performance
      - add USB TX flow control by tracking in-flight URBs
 
  - Cellular:
    - IPA v5.2 support
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core & protocols:

   - Support HW queue leasing, allowing containers to be granted access
     to HW queues for zero-copy operations and AF_XDP

   - Number of code moves to help the compiler with inlining. Avoid
     output arguments for returning drop reason where possible

   - Rework drop handling within qdiscs to include more metadata about
     the reason and dropping qdisc in the tracepoints

   - Remove the rtnl_lock use from IP Multicast Routing

   - Pack size information into the Rx Flow Steering table pointer
     itself. This allows making the table itself a flat array of u32s,
     thus making the table allocation size a power of two

   - Report TCP delayed ack timer information via socket diag

   - Add ip_local_port_step_width sysctl to allow distributing the
     randomly selected ports more evenly throughout the allowed space

   - Add support for per-route tunsrc in IPv6 segment routing

   - Start work of switching sockopt handling to iov_iter

   - Improve dynamic recvbuf sizing in MPTCP, limit burstiness and avoid
     buffer size drifting up

   - Support MSG_EOR in MPTCP

   - Add stp_mode attribute to the bridge driver for STP mode selection.
     This addresses concerns about call_usermodehelper() usage

   - Remove UDP-Lite support (as announced in 2023)

   - Remove support for building IPv6 as a module. Remove the now
     unnecessary function calling indirection

  Cross-tree stuff:

   - Move Michael MIC code from generic crypto into wireless, it's
     considered insecure but some WiFi networks still need it

  Netfilter:

   - Switch nft_fib_ipv6 module to no longer need temporary dst_entry
     object allocations by using fib6_lookup() + RCU.

     Florian W reports this gets us ~13% higher packet rate

   - Convert IPVS's global __ip_vs_mutex to per-net service_mutex and
     switch the service tables to be per-net. Convert some code that
     walks the service lists to use RCU instead of the service_mutex

   - Add more opinionated input validation to lower security exposure

   - Make IPVS hash tables to be per-netns and resizable

  Wireless:

   - Finished assoc frame encryption/EPPKE/802.1X-over-auth

   - Radar detection improvements

   - Add 6 GHz incumbent signal detection APIs

   - Multi-link support for FILS, probe response templates and client
     probing

   - New APIs and mac80211 support for NAN (Neighbor Aware Networking,
     aka Wi-Fi Aware) so less work must be in firmware

  Driver API:

   - Add numerical ID for devlink instances (to avoid having to create
     fake bus/device pairs just to have an ID). Support shared devlink
     instances which span multiple PFs

   - Add standard counters for reporting pause storm events (implement
     in mlx5 and fbnic)

   - Add configuration API for completion writeback buffering (implement
     in mana)

   - Support driver-initiated change of RSS context sizes

   - Support DPLL monitoring input frequency (implement in zl3073x)

   - Support per-port resources in devlink (implement in mlx5)

  Misc:

   - Expand the YAML spec for Netfilter

  Drivers

   - Software:
      - macvlan: support multicast rx for bridge ports with shared
        source MAC address
      - team: decouple receive and transmit enablement for IEEE 802.3ad
        LACP "independent control"

   - Ethernet high-speed NICs:
      - nVidia/Mellanox:
         - support high order pages in zero-copy mode (for payload
           coalescing)
         - support multiple packets in a page (for systems with 64kB
           pages)
      - Broadcom 25-400GE (bnxt):
         - implement XDP RSS hash metadata extraction
         - add software fallback for UDP GSO, lowering the IOMMU cost
      - Broadcom 800GE (bnge):
         - add link status and configuration handling
         - add various HW and SW statistics
      - Marvell/Cavium:
         - NPC HW block support for cn20k
      - Huawei (hinic3):
         - add mailbox / control queue
         - add rx VLAN offload
         - add driver info and link management

   - Ethernet NICs:
      - Marvell/Aquantia:
         - support reading SFP module info on some AQC100 cards
      - Realtek PCI (r8169):
         - add support for RTL8125cp
      - Realtek USB (r8152):
         - support for the RTL8157 5Gbit chip
         - add 2500baseT EEE status/configuration support

   - Ethernet NICs embedded and off-the-shelf IP:
      - Synopsys (stmmac):
         - cleanup and reorganize SerDes handling and PCS support
         - cleanup descriptor handling and per-platform data
         - cleanup and consolidate MDIO defines and handling
         - shrink driver memory use for internal structures
         - improve Tx IRQ coalescing
         - improve TCP segmentation handling
         - add support for Spacemit K3
      - Cadence (macb):
         - support PHYs that have inband autoneg disabled with GEM
         - support IEEE 802.3az EEE
         - rework usrio capabilities and handling
      - AMD (xgbe):
         - improve power management for S0i3
         - improve TX resilience for link-down handling

   - Virtual:
      - Google cloud vNIC:
         - support larger ring sizes in DQO-QPL mode
         - improve HW-GRO handling
         - support UDP GSO for DQO format
      - PCIe NTB:
         - support queue count configuration

   - Ethernet PHYs:
      - automatically disable PHY autonomous EEE if MAC is in charge
      - Broadcom:
         - add BCM84891/BCM84892 support
      - Micrel:
         - support for LAN9645X internal PHY
      - Realtek:
         - add RTL8224 pair order support
         - support PHY LEDs on RTL8211F-VD
         - support spread spectrum clocking (SSC)
      - Maxlinear:
         - add PHY-level statistics via ethtool

   - Ethernet switches:
      - Maxlinear (mxl862xx):
         - support for bridge offloading
         - support for VLANs
         - support driver statistics

   - Bluetooth:
      - large number of fixes and new device IDs
      - Mediatek:
         - support MT6639 (MT7927)
         - support MT7902 SDIO

   - WiFi:
      - Intel (iwlwifi):
         - UNII-9 and continuing UHR work
      - MediaTek (mt76):
         - mt7996/mt7925 MLO fixes/improvements
         - mt7996 NPU support (HW eth/wifi traffic offload)
      - Qualcomm (ath12k):
         - monitor mode support on IPQ5332
         - basic hwmon temperature reporting
         - support IPQ5424
      - Realtek:
         - add USB RX aggregation to improve performance
         - add USB TX flow control by tracking in-flight URBs

   - Cellular:
      - IPA v5.2 support"

* tag 'net-next-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1561 commits)
  net: pse-pd: fix kernel-doc function name for pse_control_find_by_id()
  wireguard: device: use exit_rtnl callback instead of manual rtnl_lock in pre_exit
  wireguard: allowedips: remove redundant space
  tools: ynl: add sample for wireguard
  wireguard: allowedips: Use kfree_rcu() instead of call_rcu()
  MAINTAINERS: Add netkit selftest files
  selftests/net: Add additional test coverage in nk_qlease
  selftests/net: Split netdevsim tests from HW tests in nk_qlease
  tools/ynl: Make YnlFamily closeable as a context manager
  net: airoha: Add missing PPE configurations in airoha_ppe_hw_init()
  net: airoha: Fix VIP configuration for AN7583 SoC
  net: caif: clear client service pointer on teardown
  net: strparser: fix skb_head leak in strp_abort_strp()
  net: usb: cdc-phonet: fix skb frags[] overflow in rx_complete()
  selftests/bpf: add test for xdp_master_redirect with bond not up
  net, bpf: fix null-ptr-deref in xdp_master_redirect() for down master
  net: airoha: Remove PCE_MC_EN_MASK bit in REG_FE_PCE_CFG configuration
  sctp: disable BH before calling udp_tunnel_xmit_skb()
  sctp: fix missing encap_port propagation for GSO fragments
  net: airoha: Rely on net_device pointer in ETS callbacks
  ...
2026-04-14 18:36:10 -07:00
Gabriel Krisman Bertazi
b80a95ccf1 udp: Force compute_score to always inline
Back in 2024 I reported a 7-12% regression on an iperf3 UDP loopback
thoughput test that we traced to the extra overhead of calling
compute_score on two places, introduced by commit f0ea27e7bf ("udp:
re-score reuseport groups when connected sockets are present").  At the
time, I pointed out the overhead was caused by the multiple calls,
associated with cpu-specific mitigations, and merged commit
50aee97d15 ("udp: Avoid call to compute_score on multiple sites") to
jump back explicitly, to force the rescore call in a single place.

Recently though, we got another regression report against a newer distro
version, which a team colleague traced back to the same root-cause.
Turns out that once we updated to gcc-13, the compiler got smart enough
to unroll the loop, undoing my previous mitigation.  Let's bite the
bullet and __always_inline compute_score on both ipv4 and ipv6 to
prevent gcc from de-optimizing it again in the future.  These functions
are only called in two places each, udpX_lib_lookup1 and
udpX_lib_lookup2, so the extra size shouldn't be a problem and it is hot
enough to be very visible in profilings.  In fact, with gcc13, forcing
the inline will prevent gcc from unrolling the fix from commit
50aee97d15, so we don't end up increasing udpX_lib_lookup2 at all.

I haven't recollected the results myself, as I don't have access to the
machine at the moment.  But the same colleague reported 4.67%
inprovement with this patch in the loopback benchmark, solving the
regression report within noise margins.

Eric Dumazet reported no size change to vmlinux when built with clang.
I report the same also with gcc-13:

scripts/bloat-o-meter vmlinux vmlinux-inline
add/remove: 0/2 grow/shrink: 4/0 up/down: 616/-416 (200)
Function                                     old     new   delta
udp6_lib_lookup2                             762     949    +187
__udp6_lib_lookup                            810     975    +165
udp4_lib_lookup2                             757     906    +149
__udp4_lib_lookup                            871     986    +115
__pfx_compute_score                           32       -     -32
compute_score                                384       -    -384
Total: Before=35011784, After=35011984, chg +0.00%

Fixes: 50aee97d15 ("udp: Avoid call to compute_score on multiple sites")
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Link: https://patch.msgid.link/20260410155936.654915-1-krisman@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-13 15:44:42 -07:00
Linus Torvalds
b7d74ea0fd vfs-7.1-rc1.kino
Please consider pulling these changes from the signed vfs-7.1-rc1.kino tag.
 
 Thanks!
 Christian
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Merge tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull vfs i_ino updates from Christian Brauner:
 "For historical reasons, the inode->i_ino field is an unsigned long,
  which means that it's 32 bits on 32 bit architectures. This has caused
  a number of filesystems to implement hacks to hash a 64-bit identifier
  into a 32-bit field, and deprives us of a universal identifier field
  for an inode.

  This changes the inode->i_ino field from an unsigned long to a u64.
  This shouldn't make any material difference on 64-bit hosts, but
  32-bit hosts will see struct inode grow by at least 4 bytes. This
  could have effects on slabcache sizes and field alignment.

  The bulk of the changes are to format strings and tracepoints, since
  the kernel itself doesn't care that much about the i_ino field. The
  first patch changes some vfs function arguments, so check that one out
  carefully.

  With this change, we may be able to shrink some inode structures. For
  instance, struct nfs_inode has a fileid field that holds the 64-bit
  inode number. With this set of changes, that field could be
  eliminated. I'd rather leave that sort of cleanups for later just to
  keep this simple"

* tag 'vfs-7.1-rc1.kino' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  nilfs2: fix 64-bit division operations in nilfs_bmap_find_target_in_group()
  EVM: add comment describing why ino field is still unsigned long
  vfs: remove externs from fs.h on functions modified by i_ino widening
  treewide: fix missed i_ino format specifier conversions
  ext4: fix signed format specifier in ext4_load_inode trace event
  treewide: change inode->i_ino from unsigned long to u64
  nilfs2: widen trace event i_ino fields to u64
  f2fs: widen trace event i_ino fields to u64
  ext4: widen trace event i_ino fields to u64
  zonefs: widen trace event i_ino fields to u64
  hugetlbfs: widen trace event i_ino fields to u64
  ext2: widen trace event i_ino fields to u64
  cachefiles: widen trace event i_ino fields to u64
  vfs: widen trace event i_ino fields to u64
  net: change sock.sk_ino and sock_i_ino() to u64
  audit: widen ino fields to u64
  vfs: widen inode hash/lookup functions to u64
2026-04-13 12:19:01 -07:00
Eric Dumazet
fb37aea2a0 net: change sk_filter_trim_cap() to return a drop_reason by value
Current return value can be replaced with the drop_reason,
reducing kernel bloat:

$ scripts/bloat-o-meter -t vmlinux.old vmlinux.new
add/remove: 0/2 grow/shrink: 1/11 up/down: 32/-603 (-571)
Function                                     old     new   delta
tcp_v6_rcv                                  3135    3167     +32
unix_dgram_sendmsg                          1731    1726      -5
netlink_unicast                              957     945     -12
netlink_dump                                1372    1359     -13
sk_filter_trim_cap                           882     858     -24
tcp_v4_rcv                                  3143    3111     -32
__pfx_tcp_filter                              32       -     -32
netlink_broadcast_filtered                  1633    1595     -38
sock_queue_rcv_skb_reason                    126      76     -50
tun_net_xmit                                1127    1074     -53
__sk_receive_skb                             690     632     -58
udpv6_queue_rcv_one_skb                      935     869     -66
udp_queue_rcv_one_skb                        919     853     -66
tcp_filter                                   154       -    -154
Total: Before=29722783, After=29722212, chg -0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260409145625.2306224-6-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-04-12 14:30:25 -07:00
Fernando Fernandez Mancera
d98adfbdd5 ipv4: drop ipv6_stub usage and use direct function calls
As IPv6 is built-in only, the ipv6_stub infrastructure is no longer
necessary.

The IPv4 stack interacts with IPv6 mainly to support IPv4 routes with
IPv6 next-hops (RFC 8950). Convert all these cross-family calls from
ipv6_stub to direct function calls. 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>
Link: https://patch.msgid.link/20260325120928.15848-8-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-29 11:21:23 -07:00
Fernando Fernandez Mancera
0557a34487 net: remove EXPORT_IPV6_MOD() and EXPORT_IPV6_MOD_GPL() macros
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>
2026-03-29 11:21:22 -07:00
Jakub Kicinski
9ebcf66cd6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-7.0-rc6).

No conflicts, or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-26 12:09:57 -07:00
Martin KaFai Lau
e537dd15d0 udp: Fix wildcard bind conflict check when using hash2
When binding a udp_sock to a local address and port, UDP uses
two hashes (udptable->hash and udptable->hash2) for collision
detection. The current code switches to "hash2" when
hslot->count > 10.

"hash2" is keyed by local address and local port.
"hash" is keyed by local port only.

The issue can be shown in the following bind sequence (pseudo code):

bind(fd1,  "[fd00::1]:8888")
bind(fd2,  "[fd00::2]:8888")
bind(fd3,  "[fd00::3]:8888")
bind(fd4,  "[fd00::4]:8888")
bind(fd5,  "[fd00::5]:8888")
bind(fd6,  "[fd00::6]:8888")
bind(fd7,  "[fd00::7]:8888")
bind(fd8,  "[fd00::8]:8888")
bind(fd9,  "[fd00::9]:8888")
bind(fd10, "[fd00::10]:8888")

/* Correctly return -EADDRINUSE because "hash" is used
 * instead of "hash2". udp_lib_lport_inuse() detects the
 * conflict.
 */
bind(fail_fd, "[::]:8888")

/* After one more socket is bound to "[fd00::11]:8888",
 * hslot->count exceeds 10 and "hash2" is used instead.
 */
bind(fd11, "[fd00::11]:8888")
bind(fail_fd, "[::]:8888")      /* succeeds unexpectedly */

The same issue applies to the IPv4 wildcard address "0.0.0.0"
and the IPv4-mapped wildcard address "::ffff:0.0.0.0". For
example, if there are existing sockets bound to
"192.168.1.[1-11]:8888", then binding "0.0.0.0:8888" or
"[::ffff:0.0.0.0]:8888" can also miss the conflict when
hslot->count > 10.

TCP inet_csk_get_port() already has the correct check in
inet_use_bhash2_on_bind(). Rename it to
inet_use_hash2_on_bind() and move it to inet_hashtables.h
so udp.c can reuse it in this fix.

Fixes: 30fff9231f ("udp: bind() optimisation")
Reported-by: Andrew Onyshchuk <oandrew@meta.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260319181817.1901357-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-23 18:46:45 -07:00
Kuniyuki Iwashima
14ce9a47c5 udp: Don't pass proto to __udp4_lib_rcv() and __udp6_lib_rcv().
UDP and UDP-Lite shared __udp4_lib_rcv() and __udp6_lib_rcv()
by passing IPPROTO_UDP or IPPROTO_UDPLITE.

Now, @proto is always IPPROTO_UDP.

Let's not pass it and rename the functions accordingly.

With this series removing a bunch of conditionals for UDP-Lite
from the fast path, udp_rr with 20,000 flows sees a 10% increase
in pps (13.3 Mpps -> 14.7 Mpps)  on an AMD EPYC 7B12 (Zen 2)
64-Core Processor platform.

[ With FDO, the baseline is much higher and the delta was ~3%,
  20.1 Mpps -> 20.7 Mpps ]

Before:

$ nstat > /dev/null; sleep 1; nstat | grep Udp
Udp6InDatagrams                 14013408           0.0
Udp6OutDatagrams                14013128           0.0

After:

$ nstat > /dev/null; sleep 1; nstat | grep Udp
Udp6InDatagrams                 15491971           0.0
Udp6OutDatagrams                15491671           0.0

$ ./scripts/bloat-o-meter vmlinux.before vmlinux.after
add/remove: 13/75 grow/shrink: 11/75 up/down: 13777/-18401 (-4624)
Function                                     old     new   delta
udp4_gro_receive                             872     866      -6
udp6_gro_receive                             910     903      -7
udp_rcv                                       32    1727   +1695
udpv6_rcv                                     32    1450   +1418
__udp4_lib_rcv                              2045       -   -2045
__udp6_lib_rcv                              2084       -   -2084
udp_unicast_rcv_skb                          160     149     -11
udp6_unicast_rcv_skb                         196     181     -15
__udp4_lib_mcast_deliver                     925     846     -79
__udp6_lib_mcast_deliver                     922     810    -112
__udp4_lib_lookup                            973     969      -4
__udp6_lib_lookup                            940     929     -11
__udp4_lib_lookup_skb                        106     100      -6
__udp6_lib_lookup_skb                         71      66      -5
udp4_lib_lookup_skb                          132     127      -5
udp6_lib_lookup_skb                           87      81      -6
udp_queue_rcv_skb                            326     356     +30
udpv6_queue_rcv_skb                          331     361     +30
udp_queue_rcv_one_skb                       1233     914    -319
udpv6_queue_rcv_one_skb                     1250     930    -320
__udp_enqueue_schedule_skb                  1067     995     -72
udp_rcv_segment                              520     480     -40
udp_post_segment_fix_csum                    120       -    -120
udp_lib_checksum_complete                    200      84    -116
udp_err                                       27    1103   +1076
udpv6_err                                     36    1417   +1381
__udp4_lib_err                              1112       -   -1112
__udp6_lib_err                              1448       -   -1448
udp_recvmsg                                 1149     994    -155
udpv6_recvmsg                               1349    1294     -55
udp_sendmsg                                 2730    2648     -82
udp_send_skb                                 909     681    -228
udpv6_sendmsg                               3022    2861    -161
udp_v6_send_skb                             1214     952    -262
...
Total: Before=18446744073748075501, After=18446744073748070877, chg -0.00%

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-16-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:46 -07:00
Kuniyuki Iwashima
68aeb21ef0 udp: Don't pass udptable to IPv4 socket lookup functions.
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>
2026-03-13 18:57:46 -07:00
Kuniyuki Iwashima
5a88b2810f udp: Remove dead check in __udp[46]_lib_lookup() for BPF.
BPF socket lookup for SO_REUSEPORT does not support UDP-Lite.

In __udp4_lib_lookup() and __udp6_lib_lookup(), it checks if
the passed udptable pointer is the same as net->ipv4.udp_table,
which is only true for UDP.

Now, the condition is always true.

Let's remove the check.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-13-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
c570bd25d8 udp: Remove udp_table in struct udp_seq_afinfo.
Since UDP and UDP-Lite had dedicated socket hash tables for
each, we have had to fetch them from different pointers for
procfs or bpf iterator.

UDP always has its global or per-netns table in
net->ipv4.udp_table and struct udp_seq_afinfo.udp_table
is NULL.

OTOH, UDP-Lite had only one global table in the pointer.

We no longer use the field.

Let's remove it and udp_get_table_seq().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-12-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
5c27385886 udp: Remove struct proto.h.udp_table.
Since UDP and UDP-Lite had dedicated socket hash tables for
each, we have had to fetch them from different pointers.

UDP always has its global or per-netns table in
net->ipv4.udp_table and struct proto.h.udp_table is NULL.

OTOH, UDP-Lite had only one global table in the pointer.

We no longer use the field.

Let's remove it and udp_get_table_prot().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-11-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
74f0cca110 udp: Remove UDPLITE_SEND_CSCOV and UDPLITE_RECV_CSCOV.
UDP-Lite supports variable-length checksum and has two socket
options, UDPLITE_SEND_CSCOV and UDPLITE_RECV_CSCOV, to control
the checksum coverage.

Let's remove the support.

setsockopt(UDPLITE_SEND_CSCOV / UDPLITE_RECV_CSCOV) was only
available for UDP-Lite and returned -ENOPROTOOPT for UDP.

Now, the options are handled in ip_setsockopt() and
ipv6_setsockopt(), which still return the same error.

getsockopt(UDPLITE_SEND_CSCOV / UDPLITE_RECV_CSCOV) was available
for UDP and always returned 0, meaning full checksum, but now
-ENOPROTOOPT is returned.

Given that getsockopt() is meaningless for UDP and even the options
are not defined under include/uapi/, this should not be a problem.

  $ man 7 udplite
  ...
  BUGS
       Where glibc support is missing, the following definitions
       are needed:

           #define IPPROTO_UDPLITE     136
           #define UDPLITE_SEND_CSCOV  10
           #define UDPLITE_RECV_CSCOV  11

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-10-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
b2a1d719be udp: Remove partial csum code in TX.
UDP TX paths also have some code for UDP-Lite partial
checksum:

  * udplite_csum() in udp_send_skb() and udp_v6_send_skb()
  * udplite_getfrag() in udp_sendmsg() and udpv6_sendmsg()

Let's remove such code.

Now, we can use IPPROTO_UDP directly instead of sk->sk_protocol
or fl6->flowi6_proto for csum_tcpudp_magic() and csum_ipv6_magic().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-9-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
c2539d4f2d udp: Remove partial csum code in RX.
UDP-Lite supports the partial checksum and the coverage is
stored in the position of the length field of struct udphdr.

In RX paths, udp4_csum_init() / udp6_csum_init() save the value
in UDP_SKB_CB(skb)->cscov and set UDP_SKB_CB(skb)->partial_cov
to 1 if the coverage is not full.

The subsequent processing diverges depending on the value,
but such paths are now dead.

Also, these functions have some code guarded for UDP:

  * udp_unicast_rcv_skb / udp6_unicast_rcv_skb
  * __udp4_lib_rcv() and __udp6_lib_rcv().

Let's remove the partial csum code and the unnecessary
guard for UDP-Lite in RX.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-8-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:45 -07:00
Kuniyuki Iwashima
7accba6fd1 udp: Remove UDP-Lite SNMP stats.
Since UDP and UDP-Lite shared most of the code, we have had
to check the protocol every time we increment SNMP stats.

Now that the UDP-Lite paths are dead, let's remove UDP-Lite
SNMP stats.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:44 -07:00
Kuniyuki Iwashima
56520b398e ipv4: Retire UDP-Lite.
We have deprecated IPv6 UDP-Lite sockets.

Let's drop support for IPv4 UDP-Lite sockets as well.

Most of the changes are similar to the IPv6 patch: removing
udplite.c and udp_impl.h, marking most functions in udp_impl.h
as static, moving the prototype for udp_recvmsg() to udp.h, and
adding INDIRECT_CALLABLE_SCOPE for it.

In addition, the INET_DIAG support for UDP-Lite is dropped.

We will remove the remaining dead code in the following patches.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:44 -07:00
Kuniyuki Iwashima
86a41d957b udp: Make udp[46]_seq_show() static.
Since commit a3d2599b24 ("ipv{4,6}/udp{,lite}: simplify proc
registration"), udp4_seq_show() and udp6_seq_show() are not
used in net/ipv4/udplite.c and net/ipv6/udplite.c.

Instead, udp_seq_ops and udp6_seq_ops are exposed to UDP-Lite.

Let's make udp4_seq_show() and udp6_seq_show() static.

udp_seq_ops and udp6_seq_ops are moved to udp_impl.h so that
we can make them static when the header is removed.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260311052020.1213705-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-13 18:57:44 -07:00
Jeff Layton
0fe27e5985
net: change sock.sk_ino and sock_i_ino() to u64
inode->i_ino is being converted to a u64. sock.sk_ino (which caches the
inode number) must also be widened to avoid truncation on 32-bit
architectures where unsigned long is only 32 bits.

Change sk_ino from unsigned long to u64, and update the return type
of sock_i_ino() to match. Fix all format strings that print the
result of sock_i_ino() (%lu -> %llu), and widen the intermediate
variables and function parameters in the diag modules that were
using int to hold the inode number.

Note that the UAPI socket diag structures (inet_diag_msg.idiag_inode,
unix_diag_msg.udiag_ino, etc.) are all __u32 and cannot be changed
without breaking the ABI. The assignments to those fields will
silently truncate, which is the existing behavior.

Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://patch.msgid.link/20260304-iino-u64-v3-3-2257ad83d372@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2026-03-06 14:31:26 +01:00
Jakub Kicinski
0b1324cdd8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
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>
2026-03-05 12:11:05 -08:00
Eric Dumazet
8341c989ac net: remove addr_len argument of recvmsg() handlers
Use msg->msg_namelen as a place holder instead of a
temporary variable, notably in inet[6]_recvmsg().

This removes stack canaries and allows tail-calls.

$ scripts/bloat-o-meter -t vmlinux.old vmlinux
add/remove: 0/0 grow/shrink: 2/19 up/down: 26/-532 (-506)
Function                                     old     new   delta
rawv6_recvmsg                                744     767     +23
vsock_dgram_recvmsg                           55      58      +3
vsock_connectible_recvmsg                     50      47      -3
unix_stream_recvmsg                          161     158      -3
unix_seqpacket_recvmsg                        62      59      -3
unix_dgram_recvmsg                            42      39      -3
tcp_recvmsg                                  546     543      -3
mptcp_recvmsg                               1568    1565      -3
ping_recvmsg                                 806     800      -6
tcp_bpf_recvmsg_parser                       983     974      -9
ip_recv_error                                588     576     -12
ipv6_recv_rxpmtu                             442     428     -14
udp_recvmsg                                 1243    1224     -19
ipv6_recv_error                             1046    1024     -22
udpv6_recvmsg                               1487    1461     -26
raw_recvmsg                                  465     437     -28
udp_bpf_recvmsg                             1027     984     -43
sock_common_recvmsg                          103      27     -76
inet_recvmsg                                 257     175     -82
inet6_recvmsg                                257     175     -82
tcp_bpf_recvmsg                              663     568     -95
Total: Before=25143834, After=25143328, chg -0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260227151120.1346573-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-03-02 18:17:17 -08:00
Kuniyuki Iwashima
6996a2d2d0 udp: Unhash auto-bound connected sk from 4-tuple hash table when disconnected.
Let's say we bind() an UDP socket to the wildcard address with a
non-zero port, connect() it to an address, and disconnect it from
the address.

bind() sets SOCK_BINDPORT_LOCK on sk->sk_userlocks (but not
SOCK_BINDADDR_LOCK), and connect() calls udp_lib_hash4() to put
the socket into the 4-tuple hash table.

Then, __udp_disconnect() calls sk->sk_prot->rehash(sk).

It computes a new hash based on the wildcard address and moves
the socket to a new slot in the 4-tuple hash table, leaving a
garbage in the chain that no packet hits.

Let's remove such a socket from 4-tuple hash table when disconnected.

Note that udp_sk(sk)->udp_portaddr_hash needs to be udpated after
udp_hash4_dec(hslot2) in udp_unhash4().

Fixes: 78c91ae2c6 ("ipv4/udp: Add 4-tuple hash for connected socket")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260227035547.3321327-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-28 07:46:24 -08:00
Eric Dumazet
2ef2b20cf4 net: annotate data-races around sk->sk_{data_ready,write_space}
skmsg (and probably other layers) are changing these pointers
while other cpus might read them concurrently.

Add corresponding READ_ONCE()/WRITE_ONCE() annotations
for UDP, TCP and AF_UNIX.

Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Reported-by: syzbot+87f770387a9e5dc6b79b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/699ee9fc.050a0220.1cd54b.0009.GAE@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jakub Sitnicki <jakub@cloudflare.com>
Cc: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20260225131547.1085509-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-02-26 19:23:03 -08:00
Linus Torvalds
bf4afc53b7 Convert 'alloc_obj' family to use the new default GFP_KERNEL argument
This was done entirely with mindless brute force, using

    git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
        xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'

to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.

Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.

For the same reason the 'flex' versions will be done as a separate
conversion.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2026-02-21 17:09:51 -08:00
Kees Cook
69050f8d6d treewide: Replace kmalloc with kmalloc_obj for non-scalar types
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:

Single allocations:	kmalloc(sizeof(TYPE), ...)
are replaced with:	kmalloc_obj(TYPE, ...)

Array allocations:	kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with:	kmalloc_objs(TYPE, COUNT, ...)

Flex array allocations:	kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with:	kmalloc_flex(*PTR, FAM, COUNT, ...)

(where TYPE may also be *VAR)

The resulting allocations no longer return "void *", instead returning
"TYPE *".

Signed-off-by: Kees Cook <kees@kernel.org>
2026-02-21 01:02:28 -08:00
Mahdi Faramarzpour
820990d665 udp: add drop count for packets in udp_prod_queue
This commit adds SNMP drop count increment for the packets in
per NUMA queues which were introduced in commit b650bf0977
("udp: remove busylock and add per NUMA queues"). note that SNMP
counters are incremented currently by the caller for skb. And
that these skbs on the intermediate queue cannot be counted
there so need similar logic in their error path.

Signed-off-by: Mahdi Faramarzpour <mahdifrmx@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260129083806.204752-1-mahdifrmx@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-30 17:18:53 -08:00
Jakub Kicinski
59ba823e68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-6.19-rc5).

No conflicts, or adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-08 11:38:33 -08:00
Eric Dumazet
e9cd04b281 udp: udplite is unlikely
Add some unlikely() annotations to speed up the fast path,
at least with clang compiler.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260105101719.2378881-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-06 17:06:03 -08:00
Eric Dumazet
e5c8eda39a udp: call skb_orphan() before skb_attempt_defer_free()
Standard UDP receive path does not use skb->destructor.

But skmsg layer does use it, since it calls skb_set_owner_sk_safe()
from udp_read_skb().

This then triggers this warning in skb_attempt_defer_free():

    DEBUG_NET_WARN_ON_ONCE(skb->destructor);

We must call skb_orphan() to fix this issue.

Fixes: 6471658dc6 ("udp: use skb_attempt_defer_free()")
Reported-by: syzbot+3e68572cf2286ce5ebe9@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/695b83bd.050a0220.1c9965.002b.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260105093630.1976085-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-06 17:05:17 -08:00
Gustavo A. R. Silva
c86af46b9c ipv4/inet_sock.h: Avoid thousands of -Wflex-array-member-not-at-end warnings
Use DEFINE_RAW_FLEX() to avoid thousands of -Wflex-array-member-not-at-end
warnings.

Remove struct ip_options_data, and adjust the rest of the code so that
flexible-array member struct ip_options_rcu::opt.__data[] ends last
in struct icmp_bxm.

Compensate for this by using the DEFINE_RAW_FLEX() helper to define each
on-stack struct instance that contained struct ip_options_data as a member,
and to define struct ip_options_rcu with a fixed on-stack size for its
nested flexible-array member opt.__data[].

Also, add a couple of code comments to prevent people from adding members
to a struct after another member that contains a flexible array.

With these changes, fix 2600 warnings of the following type:

include/net/inet_sock.h:65:33: warning: structure containing a flexible array member is not at the end of another structure [-Wflex-array-member-not-at-end]

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://patch.msgid.link/aVteBadWA6AbTp7X@kspp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-01-06 17:02:52 -08:00
Kees Cook
449f68f8ff net: Convert proto callbacks from sockaddr to sockaddr_unsized
Convert struct proto pre_connect(), connect(), bind(), and bind_add()
callback function prototypes from struct sockaddr to struct sockaddr_unsized.
This does not change per-implementation use of sockaddr for passing around
an arbitrarily sized sockaddr struct. Those will be addressed in future
patches.

Additionally removes the no longer referenced struct sockaddr from
include/net/inet_common.h.

No binary changes expected.

Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-5-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-11-04 19:10:33 -08:00
Eric Dumazet
6de1dec1c1 udp: do not use skb_release_head_state() before skb_attempt_defer_free()
Michal reported and bisected an issue after recent adoption
of skb_attempt_defer_free() in UDP.

The issue here is that skb_release_head_state() is called twice per skb,
one time from skb_consume_udp(), then a second time from skb_defer_free_flush()
and napi_consume_skb().

As Sabrina suggested, remove skb_release_head_state() call from
skb_consume_udp().

Add a DEBUG_NET_WARN_ON_ONCE(skb_nfct(skb)) in skb_attempt_defer_free()

Many thanks to Michal, Sabrina, Paolo and Florian for their help.

Fixes: 6471658dc6 ("udp: use skb_attempt_defer_free()")
Reported-and-bisected-by: Michal Kubecek <mkubecek@suse.cz>
Closes: https://lore.kernel.org/netdev/gpjh4lrotyephiqpuldtxxizrsg6job7cvhiqrw72saz2ubs3h@g6fgbvexgl3r/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Michal Kubecek <mkubecek@suse.cz>
Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: Florian Westphal <fw@strlen.de>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20251015052715.4140493-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-10-16 16:03:07 +02:00
Eric Dumazet
b650bf0977 udp: remove busylock and add per NUMA queues
busylock was protecting UDP sockets against packet floods,
but unfortunately was not protecting the host itself.

Under stress, many cpus could spin while acquiring the busylock,
and NIC had to drop packets. Or packets would be dropped
in cpu backlog if RPS/RFS were in place.

This patch replaces the busylock by intermediate
lockless queues. (One queue per NUMA node).

This means that fewer number of cpus have to acquire
the UDP receive queue lock.

Most of the cpus can either:
- immediately drop the packet.
- or queue it in their NUMA aware lockless queue.

Then one of the cpu is chosen to process this lockless queue
in a batch.

The batch only contains packets that were cooked on the same
NUMA node, thus with very limited latency impact.

Tested:

DDOS targeting a victim UDP socket, on a platform with 6 NUMA nodes
(Intel(R) Xeon(R) 6985P-C)

Before:

nstat -n ; sleep 1 ; nstat | grep Udp
Udp6InDatagrams                 1004179            0.0
Udp6InErrors                    3117               0.0
Udp6RcvbufErrors                3117               0.0

After:
nstat -n ; sleep 1 ; nstat | grep Udp
Udp6InDatagrams                 1116633            0.0
Udp6InErrors                    14197275           0.0
Udp6RcvbufErrors                14197275           0.0

We can see this host can now proces 14.2 M more packets per second
while under attack, and the victim socket can receive 11 % more
packets.

I used a small bpftrace program measuring time (in us) spent in
__udp_enqueue_schedule_skb().

Before:

@udp_enqueue_us[398]:
[0]                24901 |@@@                                                 |
[1]                63512 |@@@@@@@@@                                           |
[2, 4)            344827 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[4, 8)            244673 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                |
[8, 16)            54022 |@@@@@@@@                                            |
[16, 32)          222134 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                   |
[32, 64)          232042 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@                  |
[64, 128)           4219 |                                                    |
[128, 256)           188 |                                                    |

After:

@udp_enqueue_us[398]:
[0]              5608855 |@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@|
[1]              1111277 |@@@@@@@@@@                                          |
[2, 4)            501439 |@@@@                                                |
[4, 8)            102921 |                                                    |
[8, 16)            29895 |                                                    |
[16, 32)           43500 |                                                    |
[32, 64)           31552 |                                                    |
[64, 128)            979 |                                                    |
[128, 256)            13 |                                                    |

Note that the remaining bottleneck for this platform is in
udp_drops_inc() because we limited struct numa_drop_counters
to only two nodes so far.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250922104240.2182559-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-23 16:38:39 -07:00
Antoine Tenart
1c7e4a6185 net: ipv4: make udp_v4_early_demux explicitly return drop reason
udp_v4_early_demux already returns drop reasons as it either returns 0
or ip_mc_validate_source, which itself returns drop reasons. Its return
value is also already used as a drop reason itself.

Makes this explicit by making it return drop reasons.

Signed-off-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20250915091958.15382-2-atenart@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-09-19 17:35:51 -07:00
Eric Dumazet
6471658dc6 udp: use skb_attempt_defer_free()
Move skb freeing from udp recvmsg() path to the cpu
which allocated/received it, as TCP did in linux-5.17.

This increases max thoughput by 20% to 30%, depending
on number of BH producers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250916160951.541279-11-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18 10:17:10 +02:00
Eric Dumazet
3cd04c8f4a udp: make busylock per socket
While having all spinlocks packed into an array was a space saver,
this also caused NUMA imbalance and hash collisions.

UDPv6 socket size becomes 1600 after this patch.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250916160951.541279-10-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18 10:17:10 +02:00
Eric Dumazet
9db27c8062 udp: add udp_drops_inc() helper
Generic sk_drops_inc() reads sk->sk_drop_counters.
We know the precise location for UDP sockets.

Move sk_drop_counters out of sock_read_rxtx
so that sock_write_rxtx starts at a cache line boundary.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250916160951.541279-9-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18 10:17:10 +02:00
Eric Dumazet
faf7b4aefd udp: update sk_rmem_alloc before busylock acquisition
Avoid piling too many producers on the busylock
by updating sk_rmem_alloc before busylock acquisition.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250916160951.541279-7-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18 10:17:10 +02:00
Eric Dumazet
9aaec660b5 udp: refine __udp_enqueue_schedule_skb() test
Commit 5a465a0da1 ("udp: Fix multiple wraparounds
of sk->sk_rmem_alloc.") allowed to slightly overshoot
sk->sk_rmem_alloc, when many cpus are trying
to feed packets to a common UDP socket.

This patch, combined with the following one reduces
false sharing on the victim socket under DDOS.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250916160951.541279-6-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-09-18 10:17:10 +02:00