Currently, packets with fixed IDs will be merged only if their
don't-fragment bit is set. This restriction is unnecessary since
packets without the don't-fragment bit will be forwarded as-is even
if they were merged together. The merged packets will be segmented
into their original forms before being forwarded, either by GSO or
by TSO. The IDs will also remain identical unless NETIF_F_TSO_MANGLEID
is set, in which case the IDs can become incrementing, which is also fine.
Clean up the code by removing the unnecessary don't-fragment checks.
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250923085908.4687-5-richardbgobert@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Only merge encapsulated packets if their outer IDs are either
incrementing or fixed, just like for inner IDs and IDs of non-encapsulated
packets.
Add another ip_fixedid bit for a total of two bits: one for outer IDs (and
for unencapsulated packets) and one for inner IDs.
This commit preserves the current behavior of GSO where only the IDs of the
inner-most headers are restored correctly.
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250923085908.4687-3-richardbgobert@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Remove is_ipv6 from napi_gro_cb and use sk->sk_family instead.
This frees up space for another ip_fixedid bit that will be added
in the next commit.
udp_sock_create always creates either a AF_INET or a AF_INET6 socket,
so using sk->sk_family is reliable. In IPv6-FOU, cfg->ipv6_v6only is
always enabled.
Signed-off-by: Richard Gobert <richardbgobert@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250923085908.4687-2-richardbgobert@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Martin KaFai Lau says:
====================
pull-request: bpf-next 2025-09-23
We've added 9 non-merge commits during the last 33 day(s) which contain
a total of 10 files changed, 480 insertions(+), 53 deletions(-).
The main changes are:
1) A new bpf_xdp_pull_data kfunc that supports pulling data from
a frag into the linear area of a xdp_buff, from Amery Hung.
This includes changes in the xdp_native.bpf.c selftest, which
Nimrod's future work depends on.
It is a merge from a stable branch 'xdp_pull_data' which has
also been merged to bpf-next.
There is a conflict with recent changes in 'include/net/xdp.h'
in the net-next tree that will need to be resolved.
2) A compiler warning fix when CONFIG_NET=n in the recent dynptr
skb_meta support, from Jakub Sitnicki.
* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next:
selftests: drv-net: Pull data before parsing headers
selftests/bpf: Test bpf_xdp_pull_data
bpf: Support specifying linear xdp packet data size for BPF_PROG_TEST_RUN
bpf: Make variables in bpf_prog_test_run_xdp less confusing
bpf: Clear packet pointers after changing packet data in kfuncs
bpf: Support pulling non-linear xdp data
bpf: Allow bpf_xdp_shrink_data to shrink a frag from head and tail
bpf: Clear pfmemalloc flag when freeing all fragments
bpf: Return an error pointer for skb metadata when CONFIG_NET=n
====================
Link: https://patch.msgid.link/20250924050303.2466356-1-martin.lau@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
Move skb_frag_t adjustment into bpf_xdp_shrink_data() and extend its
functionality to be able to shrink an xdp fragment from both head and
tail. In a later patch, bpf_xdp_pull_data() will reuse it to shrink an
xdp fragment from head.
Additionally, in bpf_xdp_frags_shrink_tail(), breaking the loop when
bpf_xdp_shrink_data() returns false (i.e., not releasing the current
fragment) is not necessary as the loop condition, offset > 0, has the
same effect. Remove the else branch to simplify the code.
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://patch.msgid.link/20250922233356.3356453-3-ameryhung@gmail.com
It is possible for bpf_xdp_adjust_tail() to free all fragments. The
kfunc currently clears the XDP_FLAGS_HAS_FRAGS bit, but not
XDP_FLAGS_FRAGS_PF_MEMALLOC. So far, this has not caused a issue when
building sk_buff from xdp_buff since all readers of xdp_buff->flags
use the flag only when there are fragments. Clear the
XDP_FLAGS_FRAGS_PF_MEMALLOC bit as well to make the flags correct.
Signed-off-by: Amery Hung <ameryhung@gmail.com>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://patch.msgid.link/20250922233356.3356453-2-ameryhung@gmail.com
Add defines for all event types and subtypes an ism device is known to
produce as it can be helpful for debugging purposes.
Introduces a generic 'struct dibs_event' and adopt ism device driver
and smc-d client accordingly. Tolerate and ignore other type and subtype
values to enable future device extensions.
SMC-D and ISM are now independent.
struct ism_dev can be moved to drivers/s390/net/ism.h.
Note that in smc, the term 'ism' is still used. Future patches could
replace that with 'dibs' or 'smc-d' as appropriate.
Signed-off-by: Julian Ruess <julianr@linux.ibm.com>
Co-developed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-15-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Use struct dibs_dmb instead of struct smc_dmb and move the corresponding
client tables to dibs_dev. Leave driver specific implementation details
like sba in the device drivers.
Register and unregister dmbs via dibs_dev_ops. A dmb is dedicated to a
single client, but a dibs device can have dmbs for more than one client.
Trigger dibs clients via dibs_client_ops->handle_irq(), when data is
received into a dmb. For dibs_loopback replace scheduling an smcd receive
tasklet with calling dibs_client_ops->handle_irq().
For loopback devices attach_dmb(), detach_dmb() and move_data() need to
access the dmb tables, so move those to dibs_dev_ops in this patch as well.
Remove remaining definitions of smc_loopback as they are no longer
required, now that everything is in dibs_loopback.
Note that struct ism_client and struct ism_dev are still required in smc
until a follow-on patch moves event handling to dibs. (Loopback does not
use events).
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-14-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Provide the dibs_dev_ops->query_remote_gid() in ism and dibs_loopback
dibs_devices. And call it in smc dibs_client.
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-13-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
It can be debated how much benefit definition of vlan ids for dibs devices
brings, as the dmbs are accessible only by a single peer anyhow. But ism
provides vlan support and smcd exploits it, so move it to dibs layer as an
optional feature.
smcd_loopback simply ignores all vlan settings, do the same in
dibs_loopback.
SMC-D and ISM have a method to use the invalid VLAN ID 1FFF
(ISM_RESERVED_VLANID), to indicate that both communication peers support
routable SMC-Dv2. Tolerate it in dibs, but move it to SMC only.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-12-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Define a uuid_t GID attribute to identify a dibs device.
SMC uses 64 Bit and 128 Bit Global Identifiers (GIDs) per device, that
need to be sent via the SMC protocol. Because the smc code uses integers,
network endianness and host endianness need to be considered. Avoid this
in the dibs layer by using uuid_t byte arrays. Future patches could change
SMC to use uuid_t. For now conversion helper functions are introduced.
ISM devices provide 64 Bit GIDs. Map them to dibs uuid_t GIDs like this:
_________________________________________
| 64 Bit ISM-vPCI GID | 00000000_00000000 |
-----------------------------------------
If interpreted as UUID [1], this would be interpreted as the UIID variant,
that is reserved for NCS backward compatibility. So it will not collide
with UUIDs that were generated according to the standard.
smc_loopback already uses version 4 UUIDs as 128 Bit GIDs, move that to
dibs loopback. A temporary change to smc_lo_query_rgid() is required,
that will be moved to dibs_loopback with a follow-on patch.
Provide gid of a dibs device as sysfs read-only attribute.
Link: https://datatracker.ietf.org/doc/html/rfc4122 [1]
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Julian Ruess <julianr@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-11-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move struct device from ism_dev and smc_lo_dev to dibs_dev, and define a
corresponding release function. Free ism_dev in ism_remove() and smc_lo_dev
in smc_lo_dev_remove().
Replace smcd->ops->get_dev(smcd) by using dibs->dev directly.
An alternative design would be to embed dibs_dev as a field in ism_dev and
do the same for other dibs device driver specific structs. However that
would have the disadvantage that each dibs device driver needs to allocate
dibs_dev and each dibs device driver needs a different device release
function. The advantage would be that ism_dev and other device driver
specific structs would be covered by device reference counts.
Signed-off-by: Julian Ruess <julianr@linux.ibm.com>
Co-developed-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-9-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move the device add() and remove() functions from ism_client to
dibs_client_ops and call add_dev()/del_dev() for ism devices and
dibs_loopback devices. dibs_client_ops->add_dev() = smcd_register_dev() for
the smc_dibs_client. This is the first step to handle ism and loopback
devices alike (as dibs devices) in the smc dibs client.
Define dibs_dev->ops and move smcd_ops->get_chid to
dibs_dev_ops->get_fabric_id() for ism and loopback devices. See below for
why this needs to be in the same patch as dibs_client_ops->add_dev().
The following changes contain intermediate steps, that will be obsoleted by
follow-on patches, once more functionality has been moved to dibs:
Use different smcd_ops and max_dmbs for ism and loopback. Follow-on patches
will change SMC-D to directly use dibs_ops instead of smcd_ops.
In smcd_register_dev() it is now necessary to identify a dibs_loopback
device before smcd_dev and smcd_ops->get_chid() are available. So provide
dibs_dev_ops->get_fabric_id() in this patch and evaluate it in
smc_ism_is_loopback().
Call smc_loopback_init() in smcd_register_dev() and call
smc_loopback_exit() in smcd_unregister_dev() to handle the functionality
that is still in smc_loopback. Follow-on patches will move all smc_loopback
code to dibs_loopback.
In smcd_[un]register_dev() use only ism device name, this will be replaced
by dibs device name by a follow-on patch.
End of changes with intermediate parts.
Allocate an smcd event workqueue for all dibs devices, although
dibs_loopback does not generate events.
Use kernel memory instead of devres memory for smcd_dev and smcd->conn.
Since commit a72178cfe8 ("net/smc: Fix dependency of SMC on ISM") an ism
device and its driver can have a longer lifetime than the smc module, so
smc should not rely on devres to free its resources [1]. It is now the
responsibility of the smc client to free smcd and smcd->conn for all dibs
devices, ism devices as well as loopback. Call client->ops->del_dev() for
all existing dibs devices in dibs_unregister_client(), so all device
related structures can be freed in the client.
When dibs_unregister_client() is called in the context of smc_exit() or
smc_core_reboot_event(), these functions have already called
smc_lgrs_shutdown() which calls smc_smcd_terminate_all(smcd) and sets
going_away. This is done a second time in smcd_unregister_dev(). This is
analogous to how smcr is handled in these functions, by calling first
smc_lgrs_shutdown() and then smc_ib_unregister_client() >
smc_ib_remove_dev(), so leave it that way. It may be worth investigating,
whether smc_lgrs_shutdown() is still required or useful.
Remove CONFIG_SMC_LO. CONFIG_DIBS_LO now controls whether a dibs loopback
device exists or not.
Link: https://www.kernel.org/doc/Documentation/driver-model/devres.txt [1]
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Link: https://patch.msgid.link/20250918110500.1731261-8-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
smcd_buf_free() calls smc_ism_unregister_dmb(lgr->smcd, buf_desc) and
then unconditionally frees buf_desc.
Remove the cleaning up of fields of buf_desc in
smc_ism_unregister_dmb(), because it is not helpful.
This removes the only usage of ISM_ERROR from the smc module. So move it
to drivers/s390/net/ism.h.
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/20250918110500.1731261-2-wintera@linux.ibm.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Today, once an inet_bind_bucket enters a state where fastreuse >= 0 or
fastreuseport >= 0 after a socket is explicitly bound to a port, it remains
in that state until all sockets are removed and the bucket is destroyed.
In this state, the bucket is skipped during ephemeral port selection in
connect(). For applications using a reduced ephemeral port
range (IP_LOCAL_PORT_RANGE socket option), this can cause faster port
exhaustion since blocked buckets are excluded from reuse.
The reason the bucket state isn't updated on port release is unclear.
Possibly a performance trade-off to avoid scanning bucket owners, or just
an oversight.
Fix it by recalculating the bucket state when a socket releases a port. To
limit overhead, each inet_bind2_bucket stores its own (fastreuse,
fastreuseport) state. On port release, only the relevant port-addr bucket
is scanned, and the overall state is derived from these.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250917-update-bind-bucket-state-on-unhash-v5-1-57168b661b47@cloudflare.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
synflood_warned had to be u32 for xchg(), but ensuring
atomicity is not really needed.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250919204856.2977245-9-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk->sk_sndbuf is read-mostly in tx path, so move it from
sock_write_tx group to more appropriate sock_read_tx.
sk->sk_err_soft was not identified previously, but
is used from tcp_ack().
Move it to sock_write_tx group for better cache locality.
Also change tcp_ack() to clear sk->sk_err_soft only if needed.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250919204856.2977245-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sk_uid and sk_protocol are read from inet6_csk_route_socket()
for each TCP transmit.
Also read from udpv6_sendmsg(), udp_sendmsg() and others.
Move them to sock_read_tx for better cache locality.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250919204856.2977245-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
inet_hash() and inet6_hash() are exactly the same.
Also, we do not need to export inet6_hash().
Let's consolidate the two into __inet_hash() and rename it to inet_hash().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250919083706.1863217-3-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
__inet_hash() is called from inet_hash() and inet6_hash with osk NULL.
Let's remove the 2nd arg from __inet_hash().
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250919083706.1863217-2-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
assoc_drv_spc is the size of psp_assoc.drv_data[].
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250918192539.1587586-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Using flags to check sk_state only makes sense to check for a subset
of states in parallel e.g. sk_fullsock(). We are not doing that
here. Compare for individual states directly.
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250918155205.2197603-4-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
It is weird to cast to a timewait_sock before checking sk_state, even
if the use is after such a check. Remove the tw local variable, and
use inet_twsk() directly in the timewait branch.
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20250918155205.2197603-3-daniel.zahka@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Cross-merge networking fixes after downstream PR (net-6.17-rc7).
No conflicts.
Adjacent changes:
drivers/net/ethernet/mellanox/mlx5/core/en/fs.h
9536fbe10c ("net/mlx5e: Add PSP steering in local NIC RX")
7601a0a462 ("net/mlx5e: Add a miss level for ipsec crypto offload")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Andrei Vagin reported that blamed commit broke CRIU.
Indeed, while we want to keep sk_uid unchanged when a socket
is cloned, we want to clear sk->sk_ino.
Otherwise, sock_diag might report multiple sockets sharing
the same inode number.
Move the clearing part from sock_orphan() to sk_set_socket(sk, NULL),
called both from sock_orphan() and sk_clone_lock().
Fixes: 5d6b58c932 ("net: lockless sock_i_ino()")
Closes: https://lore.kernel.org/netdev/aMhX-VnXkYDpKd9V@google.com/
Closes: https://github.com/checkpoint-restore/criu/issues/2744
Reported-by: Andrei Vagin <avagin@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Andrei Vagin <avagin@google.com>
Link: https://patch.msgid.link/20250917135337.1736101-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Create psp_dev_rcv(), which drivers can call to psp decapsulate and attach
a psp_skb_ext to an skb.
psp_dev_rcv() only supports what the PSP architecture specification
refers to as "transport mode" packets, where the L3 header is either
IPv6 or IPv4.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-18-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Create a new function psp_encapsulate(), which takes a TCP packet and
PSP encapsulates it according to the "Transport Mode Packet Format"
section of the PSP Architecture Specification.
psp_encapsulate() does not push a PSP trailer onto the skb. Both IPv6
and IPv4 are supported. Virtualization cookie is not included.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Raed Salem <raeds@nvidia.com>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
Signed-off-by: Cosmin Ratiu <cratiu@nvidia.com>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-14-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
There is a (somewhat theoretical in absence of multi-host support)
possibility that another entity will rotate the key and we won't
know. This may lead to accepting packets with matching SPI but
which used different crypto keys than we expected.
The PSP Architecture specification mentions that an implementation
should track device key generation when device keys are managed by the
NIC. Some PSP implementations may opt to include this key generation
state in decryption metadata each time a device key is used to decrypt
a packet. If that is the case, that key generation counter can also be
used when policy checking a decrypted skb against a psp_assoc. This is
an optional feature that is not explicitly part of the PSP spec, but
can provide additional security in the case where an attacker may have
the ability to force key rotations faster than rekeying can occur.
Since we're tracking "key generations" more explicitly now,
maintain different lists for associations from different generations.
This way we can catch stale associations (the user space should
listen to rotation notifications and change the keys).
Drivers can "opt out" of generation tracking by setting
the generation value to 0.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-11-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
PSP eats 40B of header space. Adjust MSS appropriately.
We can either modify tcp_mtu_to_mss() / tcp_mss_to_mtu()
or reuse icsk_ext_hdr_len. The former option is more TCP
specific and has runtime overhead. The latter is a bit
of a hack as PSP is not an ext_hdr. If one squints hard
enough, UDP encap is just a more practical version of
IPv6 exthdr, so go with the latter. Happy to change.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-10-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add the ability to install PSP Rx and Tx crypto keys on TCP
connections. Netlink ops are provided for both operations.
Rx side combines allocating a new Rx key and installing it
on the socket. Theoretically these are separate actions,
but in practice they will always be used one after the
other. We can add distinct "alloc" and "install" ops later.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-9-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Provide a callback to validate skb's originating from tcp timewait
socks before passing to the device layer. Full socks have a
sk_validate_xmit_skb member for checking that a device is capable of
performing offloads required for transmitting an skb. With psp, tcp
timewait socks will inherit the crypto state from their corresponding
full socks. Any ACKs or RSTs that originate from a tcp timewait sock
carrying psp state should be psp encapsulated.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-8-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Move definition of sk_validate_xmit_skb() from net/core/sock.c to
net/core/dev.c.
This change is in preparation of the next patch, where
sk_validate_xmit_skb() will need to cast sk to a tcp_timewait_sock *,
and access member fields. Including linux/tcp.h from linux/sock.h
creates a circular dependency, and dev.c is the only current call site
of this function.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-7-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Rotating the device key is a key part of the PSP protocol design.
Some external daemon needs to do it once a day, or so.
Add a netlink op to perform this operation.
Add a notification group for informing users that key has been
rotated and they should rekey (next rotation will cut them off).
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-6-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add validation points and state propagation to support PSP key
exchange inline, on TCP connections. The expectation is that
application will use some well established mechanism like TLS
handshake to establish a secure channel over the connection and
if both endpoints are PSP-capable - exchange and install PSP keys.
Because the connection can existing in PSP-unsecured and PSP-secured
state we need to make sure that there are no race conditions or
retransmission leaks.
On Tx - mark packets with the skb->decrypted bit when PSP key
is at the enqueue time. Drivers should only encrypt packets with
this bit set. This prevents retransmissions getting encrypted when
original transmission was not. Similarly to TLS, we'll use
sk->sk_validate_xmit_skb to make sure PSP skbs can't "escape"
via a PSP-unaware device without being encrypted.
On Rx - validation is done under socket lock. This moves the validation
point later than xfrm, for example. Please see the documentation patch
for more details on the flow of securing a connection, but for
the purpose of this patch what's important is that we want to
enforce the invariant that once connection is secured any skb
in the receive queue has been encrypted with PSP.
Add GRO and coalescing checks to prevent PSP authenticated data from
being combined with cleartext data, or data with non-matching PSP
state. On Rx, check skb's with psp_skb_coalesce_diff() at points
before psp_sk_rx_policy_check(). After skb's are policy checked and on
the socket receive queue, skb_cmp_decrypted() is sufficient for
checking for coalescable PSP state. On Tx, tcp_write_collapse_fence()
should be called when transitioning a socket into PSP Tx state to
prevent data sent as cleartext from being coalesced with PSP
encapsulated data.
This change only adds the validation points, for ease of review.
Subsequent change will add the ability to install keys, and flesh
the enforcement logic out
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-5-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add pointers to psp data structures to core networking structs,
and an SKB extension to carry the PSP information from the drivers
to the socket layer.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Co-developed-by: Daniel Zahka <daniel.zahka@gmail.com>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-4-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Add a netlink family for PSP and allow drivers to register support.
The "PSP device" is its own object. This allows us to perform more
flexible reference counting / lifetime control than if PSP information
was part of net_device. In the future we should also be able
to "delegate" PSP access to software devices, such as *vlan, veth
or netkit more easily.
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Daniel Zahka <daniel.zahka@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250917000954.859376-3-daniel.zahka@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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>
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>
ipv6_pinfo.daddr_cache is either NULL or &sk->sk_v6_daddr
We do not need 8 bytes, a boolean is enough.
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/20250916160951.541279-3-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
ipv6_pinfo.saddr_cache is either NULL or &np->saddr.
We do not need 8 bytes, a boolean is enough.
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/20250916160951.541279-2-edumazet@google.com
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
The AccECN option ceb/cep heuristic algorithm is from AccECN spec
Appendix A.2.2 to mitigate against false ACE field overflows. Armed
with ceb delta from option, delivered bytes, and delivered packets it
is possible to estimate how many times ACE field wrapped.
This calculation is necessary only if more than one wrap is possible.
Without SACK, delivered bytes and packets are not always trustworthy in
which case TCP falls back to the simpler no-or-all wraps ceb algorithm.
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250916082434.100722-10-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
AccECN option may fail in various way, handle these:
- Attempt to negotiate the use of AccECN on the 1st retransmitted SYN
- From the 2nd retransmitted SYN, stop AccECN negotiation
- Remove option from SYN/ACK rexmits to handle blackholes
- If no option arrives in SYN/ACK, assume Option is not usable
- If an option arrives later, re-enabled
- If option is zeroed, disable AccECN option processing
This patch use existing padding bits in tcp_request_sock and
holes in tcp_sock without increasing the size.
Signed-off-by: Ilpo Järvinen <ij@kernel.org>
Signed-off-by: Chia-Yu Chang <chia-yu.chang@nokia-bell-labs.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250916082434.100722-9-chia-yu.chang@nokia-bell-labs.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
