Add the ability to append the incoming IP interface information to
ICMPv6 error messages in accordance with RFC 5837 and RFC 4884. This is
required for more meaningful traceroute results in unnumbered networks.
The feature is disabled by default and controlled via a new sysctl
("net.ipv6.icmp.errors_extension_mask") which accepts a bitmask of ICMP
extensions to append to ICMP error messages. Currently, only a single
value is supported, but the interface and the implementation should be
able to support more extensions, if needed.
Clone the skb and copy the relevant data portions before modifying the
skb as the caller of icmp6_send() still owns the skb after the function
returns. This should be fine since by default ICMP error messages are
rate limited to 1000 per second and no more than 1 per second per
specific host.
Trim or pad the packet to 128 bytes before appending the ICMP extension
structure in order to be compatible with legacy applications that assume
that the ICMP extension structure always starts at this offset (the
minimum length specified by RFC 4884).
Since commit 20e1954fe2 ("ipv6: RFC 4884 partial support for SIT/GRE
tunnels") it is possible for icmp6_send() to be called with an skb that
already contains ICMP extensions. This can happen when we receive an
ICMPv4 message with extensions from a tunnel and translate it to an
ICMPv6 message towards an IPv6 host in the overlay network. I could not
find an RFC that supports this behavior, but it makes sense to not
overwrite the original extensions that were appended to the packet.
Therefore, avoid appending extensions if the length field in the
provided ICMPv6 header is already filled.
Export netdev_copy_name() using EXPORT_IPV6_MOD_GPL() to make it
available to IPv6 when it is built as a module.
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251027082232.232571-3-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add the ability to append the incoming IP interface information to
ICMPv4 error messages in accordance with RFC 5837 and RFC 4884. This is
required for more meaningful traceroute results in unnumbered networks.
The feature is disabled by default and controlled via a new sysctl
("net.ipv4.icmp_errors_extension_mask") which accepts a bitmask of ICMP
extensions to append to ICMP error messages. Currently, only a single
value is supported, but the interface and the implementation should be
able to support more extensions, if needed.
Clone the skb and copy the relevant data portions before modifying the
skb as the caller of __icmp_send() still owns the skb after the function
returns. This should be fine since by default ICMP error messages are
rate limited to 1000 per second and no more than 1 per second per
specific host.
Trim or pad the packet to 128 bytes before appending the ICMP extension
structure in order to be compatible with legacy applications that assume
that the ICMP extension structure always starts at this offset (the
minimum length specified by RFC 4884).
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251027082232.232571-2-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Function udp_v4_early_demux() was already declared in 'include/net/udp.h',
no need to keep the extern in 'ip_input.c', which may produce the
following checkpatch warning:
WARNING: externs should be avoided in .c files
#45: FILE: net/ipv4/ip_input.c:322:
+enum skb_drop_reason udp_v4_early_demux(struct sk_buff *skb);
Replace it by including 'net/udp.h'. Do the same for tcp_v4_early_demux().
Signed-off-by: Wang Liang <wangliang74@huawei.com>
Link: https://patch.msgid.link/20251025092637.1020960-1-wangliang74@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Fix kernel-doc warnings in tcp_lp.c by adding missing parameter
descriptions for tcp_lp_cong_avoid() and tcp_lp_pkts_acked() when
building with W=1.
Also replace invalid URLs in the file header comment with the currently
valid links to the TCP-LP paper and implementation page.
No functional changes.
Signed-off-by: Rakuram Eswaran <rakuram.e96@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251025-net_ipv4_tcp_lp_c-v1-1-058cc221499e@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
'struct sctp_sched_ops' is not modified in these drivers.
Constifying this structure moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig, as an example:
Before:
======
text data bss dec hex filename
8019 568 0 8587 218b net/sctp/stream_sched_fc.o
After:
=====
text data bss dec hex filename
8275 312 0 8587 218b net/sctp/stream_sched_fc.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://patch.msgid.link/dce03527eb7b7cc8a3c26d5cdac12bafe3350135.1761377890.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Add likely() and unlikely() clauses for the common cases:
Device is running.
Queue is not full.
Queue is less than half capacity.
Add max_backlog parameter to skb_flow_limit() to avoid
a second READ_ONCE(net_hotdata.max_backlog).
skb_flow_limit() does not need the backlog_lock protection,
and can be called before we acquire the lock, for even better
resistance to attacks.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251024090517.3289181-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Each time some payload is consumed by user space (recvmsg() and friends),
TCP calls tcp_rcv_space_adjust() to run DRS algorithm to check
if an increase of sk->sk_rcvbuf is needed.
This function is based on time sampling, and currently calls
tcp_mstamp_refresh(tp), which is a wrapper around ktime_get_ns().
ktime_get_ns() has a high cost on some platforms.
100+ cycles for rdtscp on AMD EPYC Turin for instance.
We do not have to refresh tp->tcp_mpstamp, using the last cached value
is enough. We only need to refresh it from __tcp_cleanup_rbuf()
if an ACK must be sent (this is a rare event).
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251024120707.3516550-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_do_peeloff() calls sock_create() to allocate and initialise
struct sock, inet_sock, and sctp_sock, but later sctp_copy_sock()
and sctp_sock_migrate() overwrite most fields.
What sctp_do_peeloff() does is more like accept().
Let's use sock_create_lite() and sctp_clone_sock().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-8-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_accept() calls sctp_v[46]_create_accept_sk() to allocate a new
socket and calls sctp_sock_migrate() to copy fields from the parent
socket to the new socket.
sctp_v4_create_accept_sk() allocates sk by sk_alloc(), initialises
it by sock_init_data(), and copy a bunch of fields from the parent
socekt by sctp_copy_sock().
sctp_sock_migrate() calls sctp_copy_descendant() to copy most fields
in sctp_sock from the parent socket by memcpy().
These can be simply replaced by sk_clone().
Let's consolidate sctp_v[46]_create_accept_sk() to sctp_clone_sock()
with sk_clone().
We will reuse sctp_clone_sock() for sctp_do_peeloff() and then remove
sctp_copy_descendant().
Note that sock_reset_flag(newsk, SOCK_ZAPPED) is not copied to
sctp_clone_sock() as sctp does not use SOCK_ZAPPED at all.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-6-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_accept() will use sk_clone_lock(), but it will be called
with the parent socket locked, and sctp_migrate() acquires the
child lock later.
Let's add no lock version of sk_clone_lock().
Note that lockdep complains if we simply use bh_lock_sock_nested().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_accept() calls sctp_v[46]_create_accept_sk() to allocate a new
socket and calls sctp_sock_migrate() to copy fields from the parent
socket to the new socket.
sctp_v[46]_create_accept_sk() calls sctp_init_sock() to initialise
sctp_sock, but most fields are overwritten by sctp_copy_descendant()
called from sctp_sock_migrate().
Things done in sctp_init_sock() but not in sctp_sock_migrate() are
the following:
1. Copy sk->sk_gso
2. Copy sk->sk_destruct (sctp_v6_init_sock())
3. Allocate sctp_sock.ep
4. Initialise sctp_sock.pd_lobby
5. Count sk_sockets_allocated_inc(), sock_prot_inuse_add(),
and SCTP_DBG_OBJCNT_INC()
Let's do these in sctp_copy_sock() and sctp_sock_migrate() and avoid
calling sk->sk_prot->init() in sctp_v[46]_create_accept_sk().
Note that sk->sk_destruct is already copied in sctp_copy_sock().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sctp_sock_migrate() is called from 2 places.
1) sctp_accept() calls sp->pf->create_accept_sk() before
sctp_sock_migrate(), and sp->pf->create_accept_sk() calls
sctp_copy_sock().
2) sctp_do_peeloff() also calls sctp_copy_sock() before
sctp_sock_migrate().
sctp_copy_sock() copies sk_sndbuf and sk_rcvbuf from the
parent socket.
Let's not copy the two fields in sctp_sock_migrate().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
SCTP_DBG_OBJCNT_INC() is called only when sctp_init_sock()
returns 0 after successfully allocating sctp_sk(sk)->ep.
OTOH, SCTP_DBG_OBJCNT_DEC() is called in sctp_close().
The code seems to expect that the socket is always exposed
to userspace once SCTP_DBG_OBJCNT_INC() is incremented, but
there is a path where the assumption is not true.
In sctp_accept(), sctp_sock_migrate() could fail after
sctp_init_sock().
Then, sk_common_release() does not call inet_release() nor
sctp_close(). Instead, it calls sk->sk_prot->destroy().
Let's move SCTP_DBG_OBJCNT_DEC() from sctp_close() to
sctp_destroy_sock().
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20251023231751.4168390-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Simon Wunderlich says:
====================
This cleanup patchset includes the following patches:
- bump version strings, by Simon Wunderlich
- use skb_crc32c() instead of skb_seq_read(), by Sven Eckelmann
* tag 'batadv-next-pullrequest-20251024' of https://git.open-mesh.org/linux-merge:
batman-adv: use skb_crc32c() instead of skb_seq_read()
batman-adv: Start new development cycle
====================
Link: https://patch.msgid.link/20251024092315.232636-1-sw@simonwunderlich.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When forwarding multicast packets, the bridge takes MDB into account when
IGMP / MLD snooping is enabled. Currently, when snooping is disabled, the
MDB is retained, even though it is not used anymore.
At the same time, during the time that snooping is disabled, the IGMP / MLD
control packets are obviously ignored, and after the snooping is reenabled,
the administrator has to assume it is out of sync. In particular, missed
join and leave messages would lead to traffic being forwarded to wrong
interfaces.
Keeping the MDB entries around thus serves no purpose, and just takes
memory. Note also that disabling per-VLAN snooping does actually flush the
relevant MDB entries.
This patch flushes non-permanent MDB entries as global snooping is
disabled.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/5e992df1bb93b88e19c0ea5819e23b669e3dde5d.1761228273.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
During a handshake, an endpoint may specify a maximum record size limit.
Currently, the kernel defaults to TLS_MAX_PAYLOAD_SIZE (16KB) for the
maximum record size. Meaning that, the outgoing records from the kernel
can exceed a lower size negotiated during the handshake. In such a case,
the TLS endpoint must send a fatal "record_overflow" alert [1], and
thus the record is discarded.
Upcoming Western Digital NVMe-TCP hardware controllers implement TLS
support. For these devices, supporting TLS record size negotiation is
necessary because the maximum TLS record size supported by the controller
is less than the default 16KB currently used by the kernel.
Currently, there is no way to inform the kernel of such a limit. This patch
adds support to a new setsockopt() option `TLS_TX_MAX_PAYLOAD_LEN` that
allows for setting the maximum plaintext fragment size. Once set, outgoing
records are no larger than the size specified. This option can be used to
specify the record size limit.
[1] https://www.rfc-editor.org/rfc/rfc8449
Signed-off-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20251022001937.20155-1-wilfred.opensource@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
neightbl_set() fetches neigh_tables[] and updates attributes under
write_lock_bh(&tbl->lock), so RTNL is not needed.
neigh_table_clear() synchronises RCU only, and rcu_dereference_rtnl()
protects nothing here.
If we released RCU after fetching neigh_tables[], there would be no
synchronisation to block neigh_table_clear() further, so RCU is held
until the end of the function.
Another option would be to protect neigh_tables[] user with SRCU
and add synchronize_srcu() in neigh_table_clear().
But, holding RCU should be fine as we hold write_lock_bh() for the
rest of neightbl_set() anyway.
Let's perform RTM_SETNEIGHTBL under RCU and drop RTNL.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251022054004.2514876-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
neightbl_dump_info() calls these functions for each neigh_tables[]
entry:
1. neightbl_fill_info() for tbl->parms
2. neightbl_fill_param_info() for tbl->parms_list (except tbl->parms)
Both functions rely on the table lock (read_lock_bh(&tbl->lock))
and RTNL is not needed.
Let's fetch the table under RCU and convert RTM_GETNEIGHTBL to RCU.
Note that the first entry of tbl->parms_list is tbl->parms.list and
embedded in neigh_table, so list_next_entry() is safe.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251022054004.2514876-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
NEIGH_VAR() is read locklessly in the fast path, and IPv6 ndisc uses
NEIGH_VAR_SET() locklessly.
The next patch will convert neightbl_dump_info() to RCU.
Let's annotate accesses to neigh_param with READ_ONCE() and WRITE_ONCE().
Note that ndisc_ifinfo_sysctl_change() uses &NEIGH_VAR() and we cannot
use '&' with READ_ONCE(), so NEIGH_VAR_PTR() is introduced.
Note also that NEIGH_VAR_INIT() does not need WRITE_ONCE() as it is before
parms is published. Also, the only user hippi_neigh_setup_dev() is no
longer called since commit e3804cbebb ("net: remove COMPAT_NET_DEV_OPS"),
which looks wrong, but probably no one uses HIPPI and RoadRunner.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251022054004.2514876-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
We will convert RTM_GETNEIGHTBL to RCU soon, where we traverse
tbl->parms_list under RCU in neightbl_dump_info().
Let's use RCU list helper for neigh_parms in neigh_parms_alloc()
and neigh_parms_release().
neigh_table_init() uses the plain list_add() for the default
neigh_parm that is embedded in the table and not yet published.
Note that neigh_parms_release() already uses call_rcu() to free
neigh_parms.
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251022054004.2514876-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The 'if (!key && hash_location)' check in tcp_inbound_md5_hash() implies
that hash_location might be null. However, later code in the function
dereferences hash_location anyway, without checking for null first.
Fortunately, there is no real bug, since tcp_inbound_md5_hash() is
called only with non-null values of hash_location.
Therefore, remove the unnecessary and misleading null check of
hash_location. This silences a Smatch static checker warning
(https://lore.kernel.org/netdev/aPi4b6aWBbBR52P1@stanley.mountain/)
Also fix the related comment at the beginning of the function.
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://patch.msgid.link/20251022221209.19716-1-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Remove the long-standing comment in unix_release_sock() that described a
behavioral difference between Linux and BSD regarding when ECONNRESET is
sent to connected UNIX sockets upon closure.
As confirmed by testing on macOS (similar to BSD behavior), ECONNRESET
is only observed for SOCK_DGRAM sockets, not for SOCK_STREAM. Meanwhile,
Linux already returns ECONNRESET in cases where a socket is closed with
unread data or is not yet accept()ed. This means the previous comment no
longer accurately describes current behavior and is misleading.
Suggested-by: Kuniyuki Iwashima <kuniyu@google.com>
Signed-off-by: Sunday Adelodun <adelodunolaoluwa@yahoo.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251021195906.20389-1-adelodunolaoluwa@yahoo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull networking fixes from Jakub Kicinski:
"Including fixes from can. Slim pickings, I'm guessing people haven't
really started testing.
Current release - new code bugs:
- eth: mlx5e:
- psp: avoid 'accel' NULL pointer dereference
- skip PPHCR register query for FEC histogram if not supported
Previous releases - regressions:
- bonding: update the slave array for broadcast mode
- rtnetlink: re-allow deleting FDB entries in user namespace
- eth: dpaa2: fix the pointer passed to PTR_ALIGN on Tx path
Previous releases - always broken:
- can: drop skb on xmit if device is in listen-only mode
- gro: clear skb_shinfo(skb)->hwtstamps in napi_reuse_skb()
- eth: mlx5e
- RX, fix generating skb from non-linear xdp_buff if program
trims frags
- make devcom init failures non-fatal, fix races with IPSec
Misc:
- some documentation formatting 'fixes'"
* tag 'net-6.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (47 commits)
net/mlx5: Fix IPsec cleanup over MPV device
net/mlx5: Refactor devcom to return NULL on failure
net/mlx5e: Skip PPHCR register query if not supported by the device
net/mlx5: Add PPHCR to PCAM supported registers mask
virtio-net: zero unused hash fields
net: phy: micrel: always set shared->phydev for LAN8814
vsock: fix lock inversion in vsock_assign_transport()
ovpn: use datagram_poll_queue for socket readiness in TCP
espintcp: use datagram_poll_queue for socket readiness
net: datagram: introduce datagram_poll_queue for custom receive queues
net: bonding: fix possible peer notify event loss or dup issue
net: hsr: prevent creation of HSR device with slaves from another netns
sctp: avoid NULL dereference when chunk data buffer is missing
ptp: ocp: Fix typo using index 1 instead of i in SMA initialization loop
net: ravb: Ensure memory write completes before ringing TX doorbell
net: ravb: Enforce descriptor type ordering
net: hibmcge: select FIXED_PHY
net: dlink: use dev_kfree_skb_any instead of dev_kfree_skb
Documentation: networking: ax25: update the mailing list info.
net: gro_cells: fix lock imbalance in gro_cells_receive()
...
Syzbot reported a potential lock inversion deadlock between
vsock_register_mutex and sk_lock-AF_VSOCK when vsock_linger() is called.
The issue was introduced by commit 687aa0c558 ("vsock: Fix
transport_* TOCTOU") which added vsock_register_mutex locking in
vsock_assign_transport() around the transport->release() call, that can
call vsock_linger(). vsock_assign_transport() can be called with sk_lock
held. vsock_linger() calls sk_wait_event() that temporarily releases and
re-acquires sk_lock. During this window, if another thread hold
vsock_register_mutex while trying to acquire sk_lock, a circular
dependency is created.
Fix this by releasing vsock_register_mutex before calling
transport->release() and vsock_deassign_transport(). This is safe
because we don't need to hold vsock_register_mutex while releasing the
old transport, and we ensure the new transport won't disappear by
obtaining a module reference first via try_module_get().
Reported-by: syzbot+10e35716f8e4929681fa@syzkaller.appspotmail.com
Tested-by: syzbot+10e35716f8e4929681fa@syzkaller.appspotmail.com
Fixes: 687aa0c558 ("vsock: Fix transport_* TOCTOU")
Cc: mhal@rbox.co
Cc: stable@vger.kernel.org
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://patch.msgid.link/20251021121718.137668-1-sgarzare@redhat.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
espintcp uses a custom queue (ike_queue) to deliver packets to
userspace. The polling logic relies on datagram_poll, which checks
sk_receive_queue, which can lead to false readiness signals when that
queue contains non-userspace packets.
Switch espintcp_poll to use datagram_poll_queue with ike_queue, ensuring
poll only signals readiness when userspace data is actually available.
Fixes: e27cca96cd ("xfrm: add espintcp (RFC 8229)")
Signed-off-by: Ralf Lici <ralf@mandelbit.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20251021100942.195010-3-ralf@mandelbit.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Some protocols using TCP encapsulation (e.g., espintcp, openvpn) deliver
userspace-bound packets through a custom skb queue rather than the
standard sk_receive_queue.
Introduce datagram_poll_queue that accepts an explicit receive queue,
and convert datagram_poll into a wrapper around datagram_poll_queue.
This allows protocols with custom skb queues to reuse the core polling
logic without relying on sk_receive_queue.
Cc: Sabrina Dubroca <sd@queasysnail.net>
Cc: Antonio Quartulli <antonio@openvpn.net>
Signed-off-by: Ralf Lici <ralf@mandelbit.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Antonio Quartulli <antonio@openvpn.net>
Link: https://patch.msgid.link/20251021100942.195010-2-ralf@mandelbit.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
HSR/PRP driver does not handle correctly having slaves/interlink devices
in a different net namespace. Currently, it is possible to create a HSR
link in a different net namespace than the slaves/interlink with the
following command:
ip link add hsr0 netns hsr-ns type hsr slave1 eth1 slave2 eth2
As there is no use-case on supporting this scenario, enforce that HSR
device link matches netns defined by IFLA_LINK_NETNSID.
The iproute2 command mentioned above will throw the following error:
Error: hsr: HSR slaves/interlink must be on the same net namespace than HSR link.
Fixes: f421436a59 ("net/hsr: Add support for the High-availability Seamless Redundancy protocol (HSRv0)")
Signed-off-by: Fernando Fernandez Mancera <fmancera@suse.de>
Link: https://patch.msgid.link/20251020135533.9373-1-fmancera@suse.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
chunk->skb pointer is dereferenced in the if-block where it's supposed
to be NULL only.
chunk->skb can only be NULL if chunk->head_skb is not. Check for frag_list
instead and do it just before replacing chunk->skb. We're sure that
otherwise chunk->skb is non-NULL because of outer if() condition.
Fixes: 90017accff ("sctp: Add GSO support")
Signed-off-by: Alexey Simakov <bigalex934@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Link: https://patch.msgid.link/20251021130034.6333-1-bigalex934@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Previously, bridge ignored all features propagation and DST retention,
only handling explicitly the GSO limits.
By switching to the new helper netdev_compute_master_upper_features(), the bridge
now expose additional features, depending on the lowers capabilities.
Since br_set_gso_limits() is already covered by the helper, it can be
removed safely.
Bridge has it's own way to update needed_headroom. So we don't need to
update it in the helper.
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20251017034155.61990-5-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some high level software drivers need to compute features from lower
devices. But each has their own implementations and may lost some
feature compute. Let's use one common function to compute features
for kinds of these devices.
The new helper uses the current bond implementation as the reference
one, as the latter already handles all the relevant aspects: netdev
features, TSO limits and dst retention.
Suggested-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20251017034155.61990-2-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
syzbot found that the local_unlock_nested_bh() call was
missing in some cases.
WARNING: possible recursive locking detected
syzkaller #0 Not tainted
--------------------------------------------
syz.2.329/7421 is trying to acquire lock:
ffffe8ffffd48888 ((&cell->bh_lock)){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
ffffe8ffffd48888 ((&cell->bh_lock)){+...}-{3:3}, at: gro_cells_receive+0x404/0x790 net/core/gro_cells.c:30
but task is already holding lock:
ffffe8ffffd48888 ((&cell->bh_lock)){+...}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
ffffe8ffffd48888 ((&cell->bh_lock)){+...}-{3:3}, at: gro_cells_receive+0x404/0x790 net/core/gro_cells.c:30
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock((&cell->bh_lock));
lock((&cell->bh_lock));
*** DEADLOCK ***
Given the introduction of @have_bh_lock variable, it seems the author
intent was to have the local_unlock_nested_bh() after the @unlock label.
Fixes: 25718fdcbd ("net: gro_cells: Use nested-BH locking for gro_cell")
Reported-by: syzbot+f9651b9a8212e1c8906f@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/68f65eb9.a70a0220.205af.0034.GAE@google.com/T/#u
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20251020161114.1891141-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The function devlink_port_region_get_by_name() incorrectly uses
region->ops->name to compare the region name. as it is not any critical
impact as ops and port_ops define as union for devlink_region but as per
code logic it should refer port_ops here.
No functional impact as ops and port_ops are part of same union,
and name is the first member of both.
Update it to use region->port_ops->name to properly reference
the name of the devlink port region.
Signed-off-by: Alok Tiwari <alok.a.tiwari@oracle.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20251020170916.1741808-1-alok.a.tiwari@oracle.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The special C-flag case expects the ADD_ADDR to be received when
switching to 'fully-established'. But for various reasons, the ADD_ADDR
could be sent after the "4th ACK", and the special case doesn't work.
On NIPA, the new test validating this special case for the C-flag failed
a few times, e.g.
102 default limits, server deny join id 0
syn rx [FAIL] got 0 JOIN[s] syn rx expected 2
Server ns stats
(...)
MPTcpExtAddAddrTx 1
MPTcpExtEchoAdd 1
Client ns stats
(...)
MPTcpExtAddAddr 1
MPTcpExtEchoAddTx 1
synack rx [FAIL] got 0 JOIN[s] synack rx expected 2
ack rx [FAIL] got 0 JOIN[s] ack rx expected 2
join Rx [FAIL] see above
syn tx [FAIL] got 0 JOIN[s] syn tx expected 2
join Tx [FAIL] see above
I had a suspicion about what the issue could be: the ADD_ADDR might have
been received after the switch to the 'fully-established' state. The
issue was not easy to reproduce. The packet capture shown that the
ADD_ADDR can indeed be sent with a delay, and the client would not try
to establish subflows to it as expected.
A simple fix is not to mark the endpoints as 'used' in the C-flag case,
when looking at creating subflows to the remote initial IP address and
port. In this case, there is no need to try.
Note: newly added fullmesh endpoints will still continue to be used as
expected, thanks to the conditions behind mptcp_pm_add_addr_c_flag_case.
Fixes: 4b1ff850e0 ("mptcp: pm: in-kernel: usable client side with C-flag")
Cc: stable@vger.kernel.org
Reviewed-by: Geliang Tang <geliang@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251020-net-mptcp-c-flag-late-add-addr-v1-1-8207030cb0e8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
UDP TX packets destructor is sock_wfree().
It suffers from a cache line bouncing in sock_def_write_space_wfree().
Instead of reading sk->sk_wmem_alloc after we just did an atomic RMW
on it, use __refcount_sub_and_test() to get the old value for free,
and pass the new value to sock_def_write_space_wfree().
Add __sock_writeable() helper.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251017133712.2842665-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Following loop in napi_skb_cache_put() is unrolled by the compiler
even if CONFIG_KASAN is not enabled:
for (i = NAPI_SKB_CACHE_HALF; i < NAPI_SKB_CACHE_SIZE; i++)
kasan_mempool_unpoison_object(nc->skb_cache[i],
kmem_cache_size(net_hotdata.skbuff_cache));
We have 32 times this sequence, for a total of 384 bytes.
48 8b 3d 00 00 00 00 net_hotdata.skbuff_cache,%rdi
e8 00 00 00 00 call kmem_cache_size
This is because kmem_cache_size() is not an inline and not const,
and kasan_unpoison_object_data() is an inline function.
Cache kmem_cache_size() result in a variable, so that
the compiler can remove dead code (and variable) when/if
CONFIG_KASAN is unset.
After this patch, napi_skb_cache_put() is inlined in its callers,
and we avoid one kmem_cache_size() call in napi_skb_cache_get()
and napi_skb_cache_get_bulk().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://patch.msgid.link/20251016182911.1132792-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cpus serving NIC interrupts and specifically TX completions are often
trapped in also restarting a busy qdisc (because qdisc was stopped by BQL
or the driver's own flow control).
When they call netdev_tx_completed_queue() or netif_tx_wake_queue(),
they call __netif_schedule() so that the queue can be run
later from net_tx_action() (involving NET_TX_SOFTIRQ)
Quite often, by the time the cpu reaches net_tx_action(), another cpu
grabbed the qdisc spinlock from __dev_xmit_skb(), and we spend too much
time spinning on this lock.
We can detect in __netif_schedule() if a cpu is already at a specific
point in __dev_xmit_skb() where we have the guarantee the queue will
be run.
This patch gives a 13 % increase of throughput on an IDPF NIC (200Gbit),
32 TX qeues, sending UDP packets of 120 bytes.
This also helps __qdisc_run() to not force a NET_TX_SOFTIRQ
if another thread is waiting in __dev_xmit_skb()
Before:
sar -n DEV 5 5|grep eth1|grep Average
Average: eth1 1496.44 52191462.56 210.00 13369396.90 0.00 0.00 0.00 54.76
After:
sar -n DEV 5 5|grep eth1|grep Average
Average: eth1 1457.88 59363099.96 205.08 15206384.35 0.00 0.00 0.00 62.29
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20251017145334.3016097-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull bpf fixes from Alexei Starovoitov:
- Replace bpf_map_kmalloc_node() with kmalloc_nolock() to fix kmemleak
imbalance in tracking of bpf_async_cb structures (Alexei Starovoitov)
- Make selftests/bpf arg_parsing.c more robust to errors (Andrii
Nakryiko)
- Fix redefinition of 'off' as different kind of symbol when I40E
driver is builtin (Brahmajit Das)
- Do not disable preemption in bpf_test_run (Sahil Chandna)
- Fix memory leak in __lookup_instance error path (Shardul Bankar)
- Ensure test data is flushed to disk before reading it (Xing Guo)
* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
selftests/bpf: Fix redefinition of 'off' as different kind of symbol
bpf: Do not disable preemption in bpf_test_run().
bpf: Fix memory leak in __lookup_instance error path
selftests: arg_parsing: Ensure data is flushed to disk before reading.
bpf: Replace bpf_map_kmalloc_node() with kmalloc_nolock() to allocate bpf_async_cb structures.
selftests/bpf: make arg_parsing.c more robust to crashes
bpf: test_run: Fix ctx leak in bpf_prog_test_run_xdp error path
Martin KaFai Lau says:
====================
pull-request: bpf-next 2025-10-16
We've added 6 non-merge commits during the last 1 day(s) which contain
a total of 18 files changed, 577 insertions(+), 38 deletions(-).
The main changes are:
1) Bypass the global per-protocol memory accounting either by setting
a netns sysctl or using bpf_setsockopt in a bpf program,
from Kuniyuki Iwashima.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
selftests/bpf: Add test for sk->sk_bypass_prot_mem.
bpf: Introduce SK_BPF_BYPASS_PROT_MEM.
bpf: Support bpf_setsockopt() for BPF_CGROUP_INET_SOCK_CREATE.
net: Introduce net.core.bypass_prot_mem sysctl.
net: Allow opt-out from global protocol memory accounting.
tcp: Save lock_sock() for memcg in inet_csk_accept().
====================
Link: https://patch.msgid.link/20251016204539.773707-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Make tcp-md5 use the MD5 library API (added in 6.18) instead of the
crypto_ahash API. This is much simpler and also more efficient:
- The library API just operates on struct md5_ctx. Just allocate this
struct on the stack instead of using a pool of pre-allocated
crypto_ahash and ahash_request objects.
- The library API accepts standard pointers and doesn't require
scatterlists. So, for hashing the headers just use an on-stack buffer
instead of a pool of pre-allocated kmalloc'ed scratch buffers.
- The library API never fails. Therefore, checking for MD5 hashing
errors is no longer necessary. Update tcp_v4_md5_hash_skb(),
tcp_v6_md5_hash_skb(), tcp_v4_md5_hash_hdr(), tcp_v6_md5_hash_hdr(),
tcp_md5_hash_key(), tcp_sock_af_ops::calc_md5_hash, and
tcp_request_sock_ops::calc_md5_hash to return void instead of int.
- The library API provides direct access to the MD5 code, eliminating
unnecessary overhead such as indirect function calls and scatterlist
management. Microbenchmarks of tcp_v4_md5_hash_skb() on x86_64 show a
speedup from 7518 to 7041 cycles (6% fewer) with skb->len == 1440, or
from 1020 to 678 cycles (33% fewer) with skb->len == 140.
Since tcp_sigpool_hash_skb_data() can no longer be used, add a function
tcp_md5_hash_skb_data() which is specialized to MD5. Of course, to the
extent that this duplicates any code, it's well worth it.
To preserve the existing behavior of TCP-MD5 support being disabled when
the kernel is booted with "fips=1", make tcp_md5_do_add() check
fips_enabled itself. Previously it relied on the error from
crypto_alloc_ahash("md5") being bubbled up. I don't know for sure that
this is actually needed, but this preserves the existing behavior.
Tested with bidirectional TCP-MD5, both IPv4 and IPv6, between a kernel
that includes this commit and a kernel that doesn't include this commit.
(Side note: please don't use TCP-MD5! It's cryptographically weak. But
as long as Linux supports it, it might as well be implemented properly.)
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Link: https://patch.msgid.link/20251014215836.115616-1-ebiggers@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Quoting Eric Dumazet:
"I do not understand the fascination with net/core/drop_monitor.c [..]
misses all the features, flexibility, scalability that 'perf',
eBPF tracing, bpftrace, .... have today."
Reword DROP_MONITOR kconfig help text to clearly state that its not
related to perf-based drop monitoring and that its safe to disable
this unless support for the older netlink-based tools is needed.
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251016115147.18503-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>