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Niklas Söderlund
2b240cfc6d net: ethernet: ravb: Add gPTP support for Gen4
While driver advertises gPTP support on Gen4 platforms it is in fact
completely broken. On R-Car Gen4 devices the RAVB module have no
internal gPTP clock as generations before it. Instead it utilizes a
system-wide gPTP clock.

This change utilizes the refactoring of the RAVB gPTP code to add
support for a system-wide clock and stops the Gen4 devices trying to use
the non-existing internal gPTP clock.

To remain backward compatible the ptp-timer property is optional.If not
present, or not enabled, the RAVB driver will no longer advertise gPTP
support to user-space.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-11-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:28 -07:00
Niklas Söderlund
ef488a9da6 dt-bindings: net: renesas,etheravb: Add optional gPTP phandle for Gen4
The RAVB module on Gen4 have no gPTP clock as part of the RAVB module
itself, instead it relies on an external system wide gPTP clock. The
gPTP clock is shared with RTSN on V4H and RSWITCH on S4.

Add an optional phandle so that the RAVB driver can find and use the
gPTP clock. Ideally this should have been a mandatory property but for
backward compatible it is optional. The RAVB module is capable of
functioning without it, but can in such cases not provided PTP
functionality.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20260921175037.4084310-10-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:27 -07:00
Niklas Söderlund
931770c199 net: ethernet: ravb: Add callback for gPTP clock index
Prepare for adding Gen4 support which have an optional external gPTP
clock. Add a callback to get the clock index and use it to determine if
the device shall report gPTP support.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-9-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:27 -07:00
Niklas Söderlund
9a85f9dfbc net: ethernet: ravb: Add callback for gPTP probe
Different generations of the RAVB IP have different needs when it probes
the gPTP timer clock. Add a callback in the PTP information to allow
each generation to probe its own way.

With this the last gPTP specific flag (gptp_ref_clk) can be removed.
However the primary motivation for the change is to prepare for Gen4
support, which compared to other generations with gPTP support does not
have the clock as part of the IP itself.

Gen4 will not need to compute GTI value as it have nowhere to write it,
as the gPTP clock is external. For this reason move the computation of
it into the newly gPTP probe specific callbacks for the RAVB IP's that
support it.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-8-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:27 -07:00
Niklas Söderlund
14bf0091dd net: ethernet: ravb: Replace gPTP flags with callbacks
Prepare for adding Gen4 support which will add a third and new way to
interact with the gPTP clock by replacing the flags for Gen2 behavior
(info->gptp) and Gen3 behavior (info->ccc_gac) with callbacks.

This will make adding Gen4 support cleaner as the code will not have "if
else if else" sprinkled all over to handle each generations special
cases.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-7-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:26 -07:00
Niklas Söderlund
121cc8a3ac net: ethernet: ravb: Propagate error from ptp_clock_register()
If the PTP clock registration failed the error is silently ignored.
Before reworking all callers of ravb_ptp_init() handle and propagate the
error so it can be used.

Link: https://sashiko.dev/#/patchset/20260610102432.3538432-2-niklas.soderlund+renesas@ragnatech.se?part=1
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-6-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:26 -07:00
Niklas Söderlund
b784f9ed2e net: ethernet: ravb: Remove redundant argument to ravb_ptp_init()
There is no need to explicitly pass the struct platform_device pointer
to ravb_ptp_init(), it can retrieve it directly from the private data
structure.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-5-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:26 -07:00
Niklas Söderlund
b9c1216c01 net: ethernet: ravb: Simplify gPTP start and stop
For devices that do not support the gPTP clock in config mode the
somewhat oddly named flag gptp is set, compared to devices that do
support the gPTP clock in config and operation mode where the flag
ccc_gac is set instead. The two flags are mutually exclusive.

For the gptp-flag devices (Gen2) the clock is tied to the AVB-DMAC, when
it is stopped so is the gPTP clock. For ccc_gac-flag devices (Gen3) the
gPTP clock is available whenever the ndev is open.

Prepare to add Gen4 support which will add a third way by cleaning the
Gen2 and Gen3 cases up a bit.

Fold the gptp-flag start and stop calls into ravb_dmac_init() and
ravb_stop_dma(), which start and stop the AVB-DMAC. There are no
functional change as all call sites to the construct:

    if (info->gptp)
        ravb_ptp_init(ndev, priv->pdev);

are always just after a call to into ravb_dmac_init() and all call sites
to the construct:

    if (info->gptp)
        ravb_ptp_stop(ndev);

are always directly followed by a call to ravb_stop_dma().

There are two special cases where the calling construct covers both the
gptp-flag and info->ccc_gac devices, one for start and one for stop. The
condition that it is preceded by a call to ravb_dmac_init(), or followed
by a call to ravb_stop_dma() are however true for them too. Reworked the
two special cases to drop the check of info->gptp.

The end result is that the gPTP clock will be started or stopped for the
gptp-flag devices in tandem with the AVB-DMAC, while the info->ccc_gac
devices will be controlled, as before, when the ndev is opened or
closed.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-4-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:25 -07:00
Niklas Söderlund
d9519789d0 net: ethernet: ravb: Move programming of gPTP timer interval
Commit f384ab481c ("net: ravb: Split GTI computation and set
operations") broke apart the operations of computing the timer interval
and programming of it. However it kept the programming of the interval
in the RAVB main logic.

Having split the two apart this can be improved further by moving the
programming to the gPTP initialization function, as the first action of
the gPTP init function is to wait for the timer interval programming to
be acknowledge by the hardware.

As an added bonus the interaction with the gPTP registers for the
programming can then also be done while holding the gPTP registers lock.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-3-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:25 -07:00
Niklas Söderlund
e8bfdd9146 net: ethernet: ravb: Remove gPTP control from WoL setup and restore
Since commit a6a85ba36f ("net: ravb: Move PTP initialization in the
driver's ndo_open API for ccc_gac platorms") the gPTP clock (if
supported) is stopped and started by opening and closing the ndev.

This makes the special case to stop and start it when resuming from WoL
redundant. As the ndev will always be closed and re-opened when
resuming the system.

Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sergey Shtylyov <sergei.shtylyov@gmail.com>
Link: https://patch.msgid.link/20260921175037.4084310-2-niklas.soderlund+renesas@ragnatech.se
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:38:24 -07:00
Jakub Kicinski
cee5db680d Merge branch 'net-ethtool-make-netdev_rss_key_fill-spread-flows-over-all-queues'
Eric Dumazet says:

====================
net: ethtool: make netdev_rss_key_fill() spread flows over all queues

netdev_rss_key_fill() hands drivers a uniformly random key. Because the
Toeplitz hash is linear over GF(2), a random key is singular for a given
header field and queue count with probability 1/2: flows differing only
in the low order bits of that field (such as a burst of consecutive
ephemeral ports) then cannot reach all RX queues. On one affected 16-queue
host, only 4 queues received traffic until the key was replaced.

Patch 1 synchronizes proc_do_rss_key() with netdev_rss_key_fill() using an
smp_wmb()/smp_rmb() pair and a boolean flag so readers of
/proc/sys/net/core/netdev_rss_key print zero bytes until the key is fully
populated.

Patch 2 keeps the key random but constrains 1008 of its 2048 bits so that,
at every 16-bit aligned position and for every power-of-two queue count up
to 256, consecutive values of a field ending there visit every queue once.
Applying the fixup on the 16-bit grid covers standard 2-tuple/4-tuple
hashes as well as encapsulated or bitmap-selected layouts (such as PSP
inner TCP ports at byte 78) without enumerating them in the core. The
fixup is a bijection onto the set of valid keys, and redraws in the ~1 in
5 case where two 32-bit windows a multiple of 8 bits apart alias.

Patch 3 adds RSS key, indirection table, and flow-hash reporting to
netdevsim so the selftest can exercise both the host key and ethtool
netlink RSS reporting in a virtual machine without hardware.

Patch 4 adds a selftest under tools/testing/selftests/drivers/net/rss_key.py
checking /proc/sys/net/core/netdev_rss_key and the live RSS key,
indirection table, and flow-hash layouts reported by a device via ethtool
netlink.
====================

Link: https://patch.msgid.link/20260922163458.3900996-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:29:57 -07:00
Eric Dumazet
c8103dd8b9 selftests: drivers: net: check the host and device RSS keys
Add a selftest under tools/testing/selftests/drivers/net/rss_key.py
checking both the host RSS key (/proc/sys/net/core/netdev_rss_key) and
the RSS key, indirection table, and flow-hash layouts reported by a
device over ethtool netlink.

When invoked without NETIF, NetDrvEnv creates a 4-queue netdevsim device,
which calls netdev_rss_key_fill() and allows exercising both the host key
and the netlink RSS reporting path in a virtual machine without special
hardware. When invoked with NETIF, it checks the key and indirection
table of that interface.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260922163458.3900996-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:28:55 -07:00
Eric Dumazet
5fd4208098 netdevsim: support reporting RSS key, indirection table, and flow hash fields
Initialize a per-device RSS key in nsim_ethtool_init() using
netdev_rss_key_fill() and wire up get_rxfh_key_size, get_rxfh_indir_size,
get_rxfh, and get_rxfh_fields on nsim_ethtool_ops.

This allows RSS selftests under tools/testing/selftests/drivers/net/ to
exercise both /proc/sys/net/core/netdev_rss_key and ethtool netlink RSS
reporting against netdevsim without requiring physical hardware.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260922163458.3900996-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:28:55 -07:00
Eric Dumazet
898d431abd net: ethtool: generate RSS keys that spread flows over all queues
netdev_rss_key_fill() returns a key made of uniformly random bytes. That
is not enough, because the Toeplitz hash is linear over GF(2).

Walking the hash input MSB first, each set bit contributes a 32-bit
sliding window of the key, and hardware indexes the indirection table with
the low order bits of the result. Only the tail of each window therefore
reaches the queue index:

        v(i) = key bits [i + 32 - q .. i + 31]

with q = log2(number of RX queues). Consecutive input bits give windows
overlapping in q - 1 positions, so the q vectors belonging to the q lowest
bits of a header field form a Toeplitz matrix built from 2 * q - 1 key
bits, rather than q * q independent ones. Over GF(2) a random Toeplitz
matrix is singular with probability exactly 1/2, whatever its size.

When it is singular, flows differing only in the low order bits of that
field cannot reach all the queues. This is not theoretical: a burst of
connections draws ephemeral ports from a narrow range, and on one affected
host only 4 of the 16 RX queues received any traffic at all, until its key
was replaced.

Keep drawing the key at random, since it is a secret that stops a remote
attacker from steering flows onto a single queue, but force the handful of
bits that decide this. Writing d[t] for key bit (lsb + 31 - t), where lsb
is the position of the least significant bit of a field in the hash input,
the matrices of all the q values up to 8 are non singular if and only if

        d[2 * i] = 1 ^ d[i] ^ d[i + 1] ^ ... ^ d[2 * i - 1]

The odd positions stay free, so this is a one pass fixup rather than a
search. It is in fact a bijection from those free positions onto the set
of the values having the property, so the key stays uniformly distributed
over that set and the whole cost is 8 bits of entropy per position.
Searching for such a key by rejection would not have been an option: a
freshly drawn one has the property everywhere with probability 2^-1008.

Apply this at every 16-bit aligned position of the key, rather than at the
offsets of the 2-tuple and 4-tuple layouts only. The core does not get to
know what a given NIC hashes. Hardware may select the bytes it feeds to
Toeplitz out of a header window with a bitmap, and hash an encapsulated
header: for PSP over UDP over IPv6 it can pick the outer addresses and the
inner TCP ports, which sit 78 bytes into the frame and read key bits well
past the 40 bytes an IPv6 4-tuple needs. Hashed fields are 16 bits wide at
the smallest and are not expected to straddle that grid, so covering the
grid covers the layouts that were never written down, at no cost in code.

This spends 8 bits of entropy per position, 1008 bits out of the 2048 bits
of netdev_rss_key, leaving 1040 bits. 8 is also the largest usable bound,
as each q constrains 2 * q - 1 bits and anything larger would make the
ranges of two adjacent positions overlap.

What the fixup leaves behind is visible structure: 8 of every 16 bits are
derived from the 8 others, so a 16-bit aligned word of the key takes only
2^8 values and about 27 of the 128 words of netdev_rss_key duplicate
another one. That much is forced rather than an artefact of this
implementation, 1040 bits spread over 128 words being a little over 8 bits
each, but it has one consequence worth removing. Two 32-bit windows a
whole number of words apart now collide with probability 2^-16 instead of
2^-32, and two input bits reading the same window are indistinguishable to
the hash, since flipping both of them leaves it unchanged. Over 500 keys,
23% of them had such a pair, where a uniformly random key has one with
probability 2^-11.

So draw another key when that happens. Four out of five pass. Which
distances to look at follows from where the structure is: covering the
multiples of 16 leaves 1.2e-3 expected colliding pairs per key, still 2.6
times the 4.6e-4 of a plain random key, and almost all of that excess sits
at a distance of 8 modulo 16. Covering every multiple of 8 brings the total
down to 4.2e-4, below what a plain random key gives over all distances, and
within a few percent of the 4.0e-4 it gives over the distances that are
left.

Two windows a multiple of 8 bits apart are two windows at the same offset
modulo 8, so this is a handful of pairwise sweeps rather than one pass over
the key per distance. DO_ONCE() runs the generator under a spinlock with
hard IRQs disabled, so keep the windows of a class in an array rather than
recomputing both sides of every pair: 116 us instead of 254 us for the
worst case, a 2048-bit key with no collision anywhere, at a cost of 512
bytes of stack.

The shared key is fixed up once and every driver prefix inherits both
properties. Move netdev_rss_key and netdev_rss_key_fill() from
net/ethtool/ioctl.c to net/ethtool/common.c, and move the netdev_rss_key
declaration out of include/linux/netdevice.h into net/core/dev.h.

Checked against an independent Toeplitz implementation: for every 16-bit
aligned position and every q in 1..8, an aligned block of 2^q consecutive
values of a field ending there lands on the 2^q queues exactly once each.
Over 20 random keys that is 20160 checks, which 50.1% of plain random keys
fail and none of the generated keys do, for an average of 502 rewritten
bits out of 2048.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260922163458.3900996-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:28:54 -07:00
Eric Dumazet
9396e37c48 net: synchronize proc_do_rss_key() with netdev_rss_key_fill()
proc_do_rss_key() reads netdev_rss_key[] without synchronization, so a
concurrent reader of /proc/sys/net/core/netdev_rss_key can observe a
partially populated key while netdev_rss_key_fill() is initializing it.

Publish a boolean flag after an smp_wmb() once netdev_rss_key_fill() has
populated netdev_rss_key[], and pair it with an smp_rmb() in
proc_do_rss_key(), printing zero bytes until the flag is set.

Fixes: 960fb622f8 ("net: provide a per host RSS key generic infrastructure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260922163458.3900996-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-25 16:28:54 -07:00
Jakub Kicinski
42a9fb3382 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR (net-7.3-rc5).

Conflicts:

drivers/net/mdio/mdio-realtek-rtl9300.c
  89a8a1eef2 ("net: mdio: realtek-rtl9300: fix RTL931x C22 extended page selection")
  cc3cb8db1e ("net: mdio: realtek-rtl9300: Add page tracking")
https://lore.kernel.org/arUZOqy73bE2pp0w@sirena.org.uk

net/8021q/vlan_dev.c
  cd5dd68267 ("vlan: ensure sufficient headroom in vlan_dev_hard_header()")
  ca6ff8dd70 ("vlan: annotate data-races in vlan_dev_priv fields")

Adjacent changes:

net/ipv6/ip6_gre.c
  dd47bcf279 ("ip6_gre: Call ip6erspan_tunnel_unlink_md() in ip6erspan_changelink().")
  cce829e2aa ("ip6_gre: Protect ip6gre_net.tunnels[][] with mutex.")

drivers/net/ethernet/meta/fbnic/fbnic_txrx.c
  b5d9e9d4d0 ("eth: fbnic: use the Rx queue napi pointer to find the napi vector")
  c0aca269ec ("eth: fbnic: Make Rx completion coalescing configurable")

drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
  d68acbf935 ("net: stmmac: selftests: Support running selftests on DSA conduits")
  85ca3292d7 ("net: stmmac: Remove ARP offload code")

drivers/net/ethernet/wangxun/libwx/wx_hw.c
  3173cba117 ("net: libwx: fix races in Tx timestamp handling")
  7042c8c193 ("net: libwx: rename wx_pf_flags to wx_flags")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 13:32:50 -07:00
Linus Torvalds
f2c53ea949 Including fixes from Bluetooth, NFC and Netfilter.
Every week in this release is record-setting for number of posted
 patches. It doesn't seem like we're creating any regressions with
 all these fixes, 3 Fixes tags here point to 7.2 commits but none
 are true regression fixes. We're trying to keep the count down,
 nonetheless.
 
 Previous releases - regressions:
 
  - net: don't require the hwtstamp NDOs when a PHY provides timestamping
 
  - ipv6: fix dst leak for uncached routes
 
  - vrf: stop corrupting skb->csum when capturing CHECKSUM_COMPLETE
    packets
 
 Previous releases - always broken:
 
  - packet: use ubuf_info completion for TX_RING packets
 
  - arp: terminate device name before lookup
 
  - ipv6: do not let ipv6_find_hdr() return an offset past the packet end
 
  - udp: remove a disconnected socket from the 4-tuple hash table
 
  - sctp: discard the rest of the packet on a stale-cookie error
 
  - eth: mlx5: Bridge, fix remaining switchdev ownership gaps on merged
    eswitch
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-7.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

Pull networking fixes from Jakub Kicinski:
 "Including fixes from Bluetooth, NFC and Netfilter.

  Every week in this release is record-setting for number of posted
  patches. It doesn't seem like we're creating any regressions with all
  these fixes, three 'Fixes' tags here point to 7.2 commits but none are
  true regression fixes. We're trying to keep the count down,
  nonetheless.

  Previous releases - regressions:

   - net: don't require the hwtstamp NDOs when a PHY provides
     timestamping

   - ipv6: fix dst leak for uncached routes

   - vrf: stop corrupting skb->csum when capturing CHECKSUM_COMPLETE
     packets

  Previous releases - always broken:

   - packet: use ubuf_info completion for TX_RING packets

   - arp: terminate device name before lookup

   - ipv6: do not let ipv6_find_hdr() return an offset past the packet
     end

   - udp: remove a disconnected socket from the 4-tuple hash table

   - sctp: discard the rest of the packet on a stale-cookie error

   - eth: mlx5: Bridge, fix remaining switchdev ownership gaps on merged
     eswitch"

[ And lots of other random network driver fixes ]

* tag 'net-7.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (189 commits)
  tcp: prevent collapsing skbs across boundary in rtx queue
  vlan: ensure sufficient headroom in vlan_dev_hard_header()
  net/sched: sch_teql: fix shadowed err in __teql_resolve()
  bridge: check llc_mac_hdr_init() return value in br_send_bpdu()
  llc: fix skb UAF and leaks on llc_mac_hdr_init() failure
  llc: reserve device headroom for allocated frames
  gve: DQO: reject TSO packets with an out of range MSS
  gve: fix TX drop when GSO MSS is too small for hw
  gve: DQO: fix header length used by gve_can_send_tso() for UDP GSO
  net: flush skb_defer_nodes in dev_cpu_dead()
  net: ethernet: stmmac: dwmac-rk: fix bulk clock leak when the PHY clock fails
  af_packet: fix integer overflow in prb_calc_retire_blk_tmo()
  tipc: Fix a data race on mon->peer_cnt in mon_timeout()
  net: phy: intel-xway: workaround 100BASE-TX Link-Up issue
  net/smc: fix UAF on lgr list traversal in smcr_port_err()
  net/rds: size a connection's path set by the transport it ends up with
  nfp: hold IPsec RX state under the XArray lock
  net: ena: fix MMIO read buffer leak on probe failure
  net: ena: fix PHC cleanup on probe failure
  net/sched: act_ct: fix helper UAF due to extensions realloc
  ...
2026-09-24 11:45:33 -07:00
Willem de Bruijn
fc6d80eb50 tcp: prevent collapsing skbs across boundary in rtx queue
tcp_write_collapse_fence() sets TCP_SKB_CB(skb)->eor = 1 on
tcp_write_queue_tail(sk) to prevent skbs queued after a switch to
device encryption from being collapsed into earlier skbs.

The fence is a no-op if all earlier data has already been transmitted
when the switch happens: sk->sk_write_queue is empty. The not yet
acknowledged earlier skbs wait in sk->tcp_rtx_queue with eor 0.

On a subsequent retransmit or SACK shift, tcp_retrans_try_collapse() or
tcp_shift_skb_data() can then merge an skb queued after the switch into
one queued before it.

Both users of the fence are affected:

- psp: devices only encrypt skbs with skb->decrypted set. The merged skb
  keeps decrypted = 0 from the earlier skb, so merged data sent after
  psp_sock_assoc_set_tx() is retransmitted in cleartext.

- tls device offload: the merged skb straddles the start marker set in
  tls_set_device_offload(). The software fallback (fill_sg_in() returns
  -EINVAL) and the mlx5, nfp and funeth drivers cannot handle such an
  skb and drop it. Every retransmit rebuilds the same skb, so the
  connection stalls.

Fix this in two places, for defense in depth:

1. Fall back to tcp_rtx_queue_tail(sk) in tcp_write_collapse_fence()
   when tcp_write_queue_tail(sk) is NULL.

2. Check !skb_cmp_decrypted(to, from) in tcp_skb_can_collapse(), as
   tcp_skb_can_collapse_rx() does on receive. skb_shift(), which both
   collapse paths call, already has a DEBUG_NET_WARN_ON_ONCE() for this
   condition.

Fixes: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Cc: stable@vger.kernel.org
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Daniel Zahka <daniel.zahka@gmail.com>
Link: https://patch.msgid.link/20260924154427.953800-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:03:42 -07:00
Jakub Kicinski
1078a38344 Merge branch 'vlan-ensure-sufficient-headroom-in-vlan_dev_hard_header'
Eric Dumazet says:

====================
vlan: ensure sufficient headroom in vlan_dev_hard_header()

Callers that only reserve ETH_HLEN or less, or skbs allocated before
dynamic device/headroom changes (such as toggling VLAN_FLAG_REORDER_HDR
or bonding/team switching slaves), can reach vlan_dev_hard_header() with
insufficient headroom and trigger skb_under_panic().

When vlan_dev_hard_header() returns -ENOMEM upon skb_cow_head() failure,
a few callers of dev_hard_header() / llc_mac_hdr_init() had pre-existing
error-handling bugs:
====================

Link: https://patch.msgid.link/20260924082951.1599377-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:01:04 -07:00
Eric Dumazet
cd5dd68267 vlan: ensure sufficient headroom in vlan_dev_hard_header()
Callers that only reserve ETH_HLEN or less (such as llc_alloc_frame()),
or skbs allocated before dynamic device/headroom changes (e.g. toggling
VLAN_FLAG_REORDER_HDR or bonding/team switching slaves), can reach
vlan_dev_hard_header() with insufficient headroom and trigger
skb_under_panic().

Use skb_cow_head() in vlan_dev_hard_header() when VLAN_FLAG_REORDER_HDR
is not set to ensure sufficient headroom for the VLAN header(s) and the
underlying device hard header.

Use READ_ONCE() to read dev->hard_header_len and dev->needed_headroom as
they can be updated concurrently under RTNL (e.g. in
vlan_transfer_features()) while vlan_dev_hard_header() runs locklessly on
the transmit path. Also avoid LL_RESERVED_SPACE(dev) here so that the
extra HH_DATA_MOD alignment padding does not trigger unnecessary
pskb_expand_head() reallocations on inner stacked VLAN devices after the
outer VLAN header has been pushed.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Zixuan Chai <petalzu987@gmail.com>
Closes: https://lore.kernel.org/netdev/cover.1789987105.git.petalzu987@gmail.com/
Link: https://lore.kernel.org/netdev/179022851638.2160803.1808206741379444999@kernel.org/
Cc: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260924082951.1599377-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:00:59 -07:00
Eric Dumazet
907b978e82 net/sched: sch_teql: fix shadowed err in __teql_resolve()
__teql_resolve() declares an inner 'int err;' inside the
'if (neigh_event_send(n, skb_res) == 0)' block, shadowing the outer
'int err = 0;'. As a result, a negative return from dev_hard_header()
is written to the inner variable and __teql_resolve() still returns 0.

Remove the shadowed variable and set the outer err to -EINVAL when
dev_hard_header() returns a negative error.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Closes: https://lore.kernel.org/netdev/179022851638.2160803.1808206741379444999@kernel.org/
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260924082951.1599377-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:00:59 -07:00
Eric Dumazet
ac704ff08e bridge: check llc_mac_hdr_init() return value in br_send_bpdu()
If llc_mac_hdr_init() fails (for instance if the port device type does
not support LLC or dev_hard_header() fails), br_send_bpdu() should drop
the skb instead of resetting the mac header to the LLC payload and
transmitting a malformed frame.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Closes: https://lore.kernel.org/netdev/179022851638.2160803.1808206741379444999@kernel.org/
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: Ido Schimmel <idosch@nvidia.com>
Cc: bridge@lists.linux.dev
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260924082951.1599377-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:00:59 -07:00
Eric Dumazet
72f9dd522f llc: fix skb UAF and leaks on llc_mac_hdr_init() failure
In llc_conn_ac_resend_i_xxx_x_set_0_or_send_rr(), if llc_mac_hdr_init()
fails, kfree_skb(skb) is called instead of kfree_skb(nskb). This leaks
the newly allocated nskb, reads from the freed skb via LLC_I_GET_NR(pdu),
and double-frees skb when llc_conn_state_process() drops its reference.

In llc_sap_action_send_xid_r() and llc_sap_action_send_test_r(), nskb is
leaked if llc_mac_hdr_init() returns an error.

Free nskb in all three error paths.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Closes: https://lore.kernel.org/netdev/179022851638.2160803.1808206741379444999@kernel.org/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260924082951.1599377-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 11:00:59 -07:00
Zixuan Chai
72b5b9a28b llc: reserve device headroom for allocated frames
llc_alloc_frame() reserves link-layer headroom using the device type.
This is insufficient for stacked Ethernet devices such as VLAN devices,
where vlan_dev_hard_header() pushes a VLAN header before the lower
device's Ethernet header. An LLC response on such a device can
therefore underflow skb headroom in eth_header().

Use LL_RESERVED_SPACE() to account for the device's actual required
headroom while preserving the existing LLC device-type check.

Fixes: bf9ae5386b ("llc: use dev_hard_header")
Cc: stable@vger.kernel.org
Reported-by: VEGA <vega@nebusec.ai>
Signed-off-by: Zixuan Chai <petalzu987@gmail.com>
Signed-off-by: Ren Wei <weir@nebusec.ai>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260924012613.2533934-1-weir@nebusec.ai
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:58:16 -07:00
Jakub Kicinski
488089055b Merge branch 'gve-dqo-fix-handling-of-out-of-range-tso-mss'
Eric Dumazet says:

====================
gve: DQO: fix handling of out of range TSO MSS

The DQO TX path assumes that the MSS of a TSO packet is within the
range supported by the device, [88, 9728].

This holds for locally generated traffic, but not for packets coming
from a tap or from a packet socket: virtio_net_hdr_to_skb() takes
gso_size from user space and only enforces a minimum, layer 2
forwarding does not check the MTU of GSO packets, and
gso_features_check() bounds skb->len and gso_segs but never gso_size.

Patch 1, from Eddie Phillips, deals with the lower bound. It moves the
existing test out of gve_prep_tso() into gve_features_check_dqo(), so
that these packets are segmented in software instead of being dropped.

Patch 2 deals with the upper bound, which is currently not checked at
all. gve_tx_fill_tso_ctx_desc() stores gso_size into a 14 bits wide
field, so that an MSS of 16384 silently becomes zero. Falling back to
software segmentation is not an option here, because skb_segment()
splits at gso_size regardless of the MTU, and would only replace an
invalid TSO packet by non TSO packets larger than the 9728 bytes the
device supports. These packets are dropped instead.

As noted in patch 2, oversized non TSO packets can still reach the
device whenever the stack segments in software. This is not specific
to gve and is better fixed in the core, so a patch for
__is_skb_forwardable() will be sent separately for net-next.
====================

Link: https://patch.msgid.link/20260924004252.1196328-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:57:01 -07:00
Eric Dumazet
296c83b5cc gve: DQO: reject TSO packets with an out of range MSS
gve_prep_tso() notes that the device requires the MSS to be <= 9728,
but does not enforce it, assuming the 9K MTU enforced by the hypervisor
and the 64KB limit on TSO sizes are enough.

This does not hold for packets that were not generated locally.
A guest behind a tap, or any packet socket user, can provide an
arbitrary gso_size in virtio_net_hdr. Layer 2 forwarding does not check
the MTU for GSO packets (is_skb_forwardable()), and gso_features_check()
only bounds skb->len and gso_segs, never gso_size.

Such a packet reaches gve_tx_fill_tso_ctx_desc(), which puts gso_size
into the mss field of the TSO context descriptor. This field is 14 bits
wide, so a gso_size of 16384 is silently turned into an MSS of zero.

Drop these packets from gve_prep_tso(), and make sure that
gve_features_check_dqo() leaves their GSO bits alone: skb_segment()
splits at gso_size regardless of the MTU, so falling back to software
segmentation would give the device non TSO packets bigger than the
9728 bytes it supports.

Note that the device can still be given oversized non TSO packets when
the stack segments in software for other reasons, for instance after
TSO has been disabled with ethtool. This is a generic issue, because
the MTU check is skipped for GSO packets in the forwarding path, and
is addressed separately.

Fixes: a57e5de476 ("gve: DQO: Add TX path")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20260924004252.1196328-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:56:59 -07:00
Eddie Phillips
3b430ea623 gve: fix TX drop when GSO MSS is too small for hw
The device has a strict requirement that the minimum MSS
(gso_size) for TSO/GSO packets must be at least 88 bytes. If a packet
below this threshold is pushed to the hardware, it can cause
hardware to silently drop the packet, leading to increased latency
and retransmissions.

Currently, this is validated too late in the transmit pipeline
(gve_prep_tso), leading to silent drops.

Fix this by moving the validation into the .ndo_features_check
callback (gve_features_check_dqo). If we detect a GSO packet with
a gso_size smaller than GVE_TX_MIN_TSO_MSS_DQO, we clear the GSO
feature flags for this packet.

Fixes: a57e5de476 ("gve: DQO: Add TX path")
Signed-off-by: Eddie Phillips <eddiephillips@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20260924004252.1196328-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:56:59 -07:00
Linus Torvalds
415f204422 Landlock fix for v7.3-rc5
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Merge tag 'landlock-7.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux

Pull Landlock fixes from Mickaël Salaün:
 "This mainly fixes the Landlock tracepoint support merged this cycle so
  that denial and rule events report the intended policy context,
  whether through tracefs or BTF-visible callbacks.

  The size of this all is mainly from propagating the corrected contract
  through event definitions and producers, adding new tests for the
  reported context, and updating the documentation.

  Also improve annotation and fix a GCC 16 build warning"

* tag 'landlock-7.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux:
  landlock: Widen ruleset versions to 64 bits
  landlock: Add counted_by in landlock_domain
  landlock: Fix tracepoint contract documentation
  selftests/landlock: Test network denial context
  selftests/landlock: Test filesystem denial blockers
  landlock: Report the effective signal number
  landlock: Report the actual ptrace tracer
  landlock: Fix network denial trace context
  landlock: Fix rule tracepoint context
  landlock: Fix filesystem denial blocker reporting
  landlock: Fix tracepoint fixed-width type names
  landlock: Work around gcc-16 -Wuninitialized warning
2026-09-24 10:53:59 -07:00
Eric Dumazet
83769c23fb gve: DQO: fix header length used by gve_can_send_tso() for UDP GSO
gve_can_send_tso() computes how many buffers each segment of a GSO
packet would span, and for this it needs the length of the headers
that the device replicates in front of every segment.

It unconditionally uses skb_tcp_all_headers(), which reads the doff
field of the TCP header. SKB_GSO_UDP_L4 packets have no TCP header:
tcp_hdrlen() then reads one byte of the UDP payload, and header_len
can be anything in [0, 60] instead of the transport offset plus the
eight bytes of the UDP header that gve_prep_tso() programs into the
TSO context descriptor.

A wrong header length shifts all the segment boundaries computed in
the loop, so the number of buffers per segment can be over or under
estimated. In the first case, GSO is needlessly disabled for this
packet by gve_features_check_dqo() and the stack has to segment it.
In the second case, the driver hands the device a packet whose
segments span more than GVE_TX_MAX_DATA_DESCS buffers.

Use the UDP header length for SKB_GSO_UDP_L4 packets, matching what
gve_prep_tso() does.

Fixes: 014c607f86 ("gve: add support for UDP GSO for DQO format")
Closes: https://lore.kernel.org/netdev/CANn89i+MS4L60sFQ49=-f-mibeveUfcrpVkD5X+Qy6SOnEpd6w@mail.gmail.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ankit Garg <nktgrg@google.com>
Cc: Harshitha Ramamurthy <hramamurthy@google.com>
Cc: Joshua Washington <joshwash@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reviewed-by: Ankit Garg <nktgrg@google.com>
Reviewed-by: Harshitha Ramamurthy <hramamurthy@google.com>
Link: https://patch.msgid.link/20260923145942.731365-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:51:29 -07:00
Eric Dumazet
06e3f54e8b net: flush skb_defer_nodes in dev_cpu_dead()
When a CPU goes offline, dev_cpu_dead() drains its softnet queues
(completion_queue, output_queue, poll_list, process_queue, and
input_pkt_queue), but leaves net_hotdata.skb_defer_nodes untouched.

If oldcpu goes offline while holding pending skbs in its
skb_defer_nodes lists (e.g. below the sysctl_skb_defer_max >> 1 IPI
threshold, or if the IPI races with CPU teardown), those skbs remain
stranded until oldcpu is brought back online. If any of these skbs
hold page_pool fragments, page_pool_destroy() will stall indefinitely
waiting for inflight pages to be returned when a netdev or driver is
torn down while oldcpu is offline.

Additionally, if smp_call_function_single_async() fails in
kick_defer_list_purge() because the target CPU went offline, reset
defer_ipi_scheduled to 0 so future IPI kicks are not blocked when the
CPU comes back online.

Also, if oldcpu was the last online CPU on its NUMA node, drain that
node's slot across all CPUs so no skbs deferred from that node remain
stranded on idle remote CPUs (or if the node itself is subsequently
offlined).

Finally, in skb_attempt_defer_free(), re-check cpu_online(cpu) and
whether the caller migrated CPUs after llist_add(), flushing the node
list if so, to close the preemption TOCTOU race against CPU/node
teardown.

Fixes: 68822bdf76 ("net: generalize skb freeing deferral to per-cpu lists")
Fixes: 5628f3fe3b ("net: add NUMA awareness to skb_attempt_defer_free()")
Closes: https://lore.kernel.org/netdev/20260916003430.3612956-1-kris.pan@intel.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kris Pan <kris.pan@intel.com>
Link: https://patch.msgid.link/20260923130318.607255-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:48:10 -07:00
Coia Prant
8db67bb6a1 net: ethernet: stmmac: dwmac-rk: fix bulk clock leak when the PHY clock fails
gmac_clk_enable() enables the bulk clocks first and then the optional
PHY clock. If clk_prepare_enable() on the PHY clock fails, the function
returns without rolling back the bulk clocks, and bsp_priv->clk_enabled
stays false, so the later gmac_clk_enable(bsp_priv, false) becomes a
no-op and the bulk clock references are leaked.

Add the missing clk_bulk_disable_unprepare() on that failure path.

Fixes: ea449f7fa0 ("net: ethernet: stmmac: dwmac-rk: rework optional clock handling")
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Acked-by: Lorenzo Bianconi <lorenzo.bianconi@oss.qualcomm.com>
Signed-off-by: Coia Prant <coiaprant@gmail.com>
Link: https://patch.msgid.link/20260923123713.3137146-1-coiaprant@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:47:24 -07:00
Dairui Zhang
56d82862a0 af_packet: fix integer overflow in prb_calc_retire_blk_tmo()
prb_calc_retire_blk_tmo() computes in 32-bit int arithmetic:

        mbits = (blk_size_in_bytes * 8) / (1024 * 1024);

If I'm reading the validation right, tp_block_size is user
controlled and packet_set_ring() only rejects values that are <= 0
as int or not page aligned, so a 256MiB block goes right through
(and alloc_one_pg_vec_page() even has a vzalloc fallback for it).
0x10000000 * 8 wraps to INT_MIN, and on a NIC reporting 1 Gbps
(div == 1) the function ends up returning -2047.

The condition is actually (8 * size) mod 2^32 >= 2^31 && div == 1,
so the trigger set is [256,512), [768,1024), [1280,1536) and
[1792,2048) MiB. Other sizes wrap to non-negative values and faster
links divide the unsigned value back below 2^31, which is why this
doesn't blow up for everyone.

What makes it fatal is what happens next in init_prb_bdqc():

        p1->interval_ktime = ms_to_ktime(prb_calc_retire_blk_tmo(...));
        hrtimer_start(&p1->retire_blk_timer, p1->interval_ktime,
                      HRTIMER_MODE_REL_SOFT);

A negative relative timeout expires immediately. The callback
unconditionally returns HRTIMER_RESTART, and hrtimer_forward() turns
the negative interval into hrtimer_resolution:

        if (interval < hrtimer_resolution)
                interval = hrtimer_resolution;

So the SOFT timer re-fires at the maximum rate forever, holding
sk_receive_queue.lock each pass. One CPU spins in softirq until the
socket is closed. Repeat with more rings and the machine is gone.

The overflow itself is ancient - it was introduced together with
TPACKET_V3 in f6fb8f100b ("af-packet: TPACKET_V3 flexible buffer
implementation."). Its effect prior to f7460d2989 ("net:
af_packet: Use hrtimer to do the retire operation", v6.18) was not
as clear-cut, though: the return value was stored into an unsigned
short retire_blk_tov, so a negative result was truncated, and a
0-jiffy delay loop could be programmed as well. Neither is nearly
as detrimental as the immediate maximum-rate spin the hrtimer
conversion turned it into.

(Unrelated to CVE-2019-20812 - that one was the ethtool failure path
returning 0, which now returns DEFAULT_PRB_RETIRE_TOV.)

Reproducer, needs CAP_NET_RAW (a --network host container has it by
default) and a 1 Gbps NIC (QEMU e1000 works):

        int fd = socket(AF_PACKET, SOCK_RAW, htons(ETH_P_ALL));
        bind(fd, ...);
        int v = TPACKET_V3;
        setsockopt(fd, SOL_PACKET, PACKET_VERSION, &v, sizeof(v));
        struct tpacket_req3 req = {
                .tp_block_size = 0x10000000,
                .tp_block_nr = 1,
                .tp_frame_size = 2048,
                .tp_frame_nr = 0x10000000 / 2048,
                .tp_retire_blk_tov = 0,
        };
        setsockopt(fd, SOL_PACKET, PACKET_RX_RING, &req, sizeof(req));

Compute in 64 bits instead. The operands are already bounded by the
existing validation, so nothing else changes. If you'd prefer a
different fix, just say so and I'll respin.

Fixes: f6fb8f100b ("af-packet: TPACKET_V3 flexible buffer implementation.")
Cc: stable@vger.kernel.org
Signed-off-by: Dairui Zhang <zhangdairui@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20260923050101.1510064-1-zhangdairui@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:40:50 -07:00
Ginger Li
8e1937fed6 tipc: Fix a data race on mon->peer_cnt in mon_timeout()
mon_timeout() evaluates dom_size(mon->peer_cnt) before it takes mon->lock,
while mon->peer_cnt is updated under that lock by tipc_mon_add_peer() and
tipc_mon_remove_peer().  The value can therefore be stale, and the decision
whether the local domain has to be recomputed can be based on an outdated
member count.

Read mon->peer_cnt inside the write_lock_bh(&mon->lock) protected region.

Fixes: 35c55c9877 ("tipc: add neighbor monitoring framework")
Signed-off-by: Ginger Li <ginger.jzllee@gmail.com>
Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech>
Link: https://patch.msgid.link/20260922080909.21123-1-ginger.jzllee@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:21:45 -07:00
Alexander Sverdlin
b94773dc4d net: phy: intel-xway: workaround 100BASE-TX Link-Up issue
MaxLinear GSW12x/GSW14x Ethernet Switch Errata Sheet states:
"An issue has been sporadically observed after device power-on on the first
link-up attempt in 100BASE-TX mode resulting in either the link-up taking a
long time, or failing to link-up altogether...

Workaround:
After power-on, enable Cable Diagnostic Mode for all ports and disable
it..."

Implement the proposed workaround unconditionally in the Intel XWAY driver
(MaxLinear GSW1xx switches incorporate Intel XWAY PHYs) because the
diagnostic bits have the same meaning even in older integral PHYs such as
GPY111/PEF7071/PHY11G. So it's not clear how to distinguish the affected
newer integrated PHYs, but the workaround should not hurt the older PHYs.

Cc: stable@vger.kernel.org
Fixes: 22335939ec ("net: dsa: add driver for MaxLinear GSW1xx switch family")
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://patch.msgid.link/20260922075251.23386-1-alexander.sverdlin@siemens.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:21:20 -07:00
Sidraya Jayagond
61cb282fe9 net/smc: fix UAF on lgr list traversal in smcr_port_err()
smcr_port_err() traverses smc_lgr_list.list without holding
smc_lgr_list.lock, allowing a concurrent smc_lgr_terminate_sched()
to free an lgr while it is still being dereferenced.

Hold smc_lgr_list.lock across the traversal. Update
smc_ib_gid_check() to call smcr_port_err() after releasing the lock.

Fixes: 541afa10c1 ("net/smc: add smcr_port_err() and smcr_link_down() processing")
Reviewed-by: Mahanta Jambigi <mjambigi@linux.ibm.com>
Signed-off-by: Sidraya Jayagond <sidraya@linux.ibm.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Link: https://patch.msgid.link/20260922073149.474762-1-sidraya@linux.ibm.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:19:50 -07:00
Allison Henderson
ba3d1f480c net/rds: size a connection's path set by the transport it ends up with
__rds_conn_create() computes npaths from the caller's transport before
it decides whether a connection to one of the host's own addresses is
to be handled by the loopback transport instead.  That substitution is
what an RDS/TCP socket sending to a local address gets, and after it
the path init loop still runs for the TCP transport's RDS_MPATH_WORKERS
paths and allocates an ordered workqueue for each, while
rds_loop_conn_alloc() only ever provides transport data for path 0.

rds_conn_destroy() sizes its teardown from c_trans, by then the
loopback transport, so it visits path 0 only - and
rds_conn_path_destroy() would skip the other paths anyway, since it
returns before destroy_workqueue() for a path without transport data.
kfree(c_path) then drops the last pointers to seven workqueues.  That
repeats for every such connection, on every netns teardown or module
unload, and every distinct local destination address is a separate
connection.

Recompute npaths once the transport is final, so that creation and
destruction agree on the set of paths.  The c_path array stays sized
for the caller's transport; the unused entries are freed with it.

Fixes: 4716af3897 ("net/rds: Give each connection path its own workqueue")
Signed-off-by: Allison Henderson <achender@kernel.org>
Link: https://patch.msgid.link/20260921215027.174657-1-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 10:03:23 -07:00
Sang-Hoon Choi
1a983a4e14 nfp: hold IPsec RX state under the XArray lock
nfp_net_ipsec_rx() drops the XArray lock before taking a reference to the
xfrm_state it found. The delete path can erase the entry and drop the last
state reference in that interval. RX can then try to increment a zero
refcount after the state has been queued for destruction.

The driver queues firmware invalidation asynchronously; the delete path
does not wait for the command to complete or drain pending RX processing.

The XFRM garbage collector waits for an RCU grace period before freeing
the state. That delays reclamation but does not make acquiring a reference
from zero valid.

Take the xfrm_state reference before releasing the XArray lock so
xa_erase() cannot run between lookup and reference acquisition.

Fixes: 57f273adbc ("nfp: add framework to support ipsec offloading")
Reported-by: Changyul Lee <lcy8047@gmail.com>
Signed-off-by: Sang-Hoon Choi <csh0052@gmail.com>
Link: https://patch.msgid.link/179001455912.44752.17153022439349797877.idr-bug-92@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:59:32 -07:00
Jakub Kicinski
5b49efa1e1 Merge branch 'net-ena-fix-resource-cleanup-on-probe-failure'
Guangshuo Li says:

====================
net: ena: fix resource cleanup on probe failure

This series fixes two resource leaks in the ena_probe() error path after
ena_device_init() has successfully initialized device resources.

Patch 1 adds the missing PHC cleanup.
Patch 2 adds the missing MMIO read request cleanup.
====================

Link: https://patch.msgid.link/20260921154202.471662-1-lgs201920130244@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:57:57 -07:00
Guangshuo Li
9476b44688 net: ena: fix MMIO read buffer leak on probe failure
ena_device_init() initializes the MMIO read mechanism with
ena_com_mmio_reg_read_request_init(), which allocates a coherent DMA
buffer for MMIO read responses.

The normal removal path releases this buffer through
ena_com_mmio_reg_read_request_destroy(). However, if ena_probe() fails
after ena_device_init() succeeds, the error path destroys the admin
resources and eventually frees ena_dev without destroying the MMIO read
request, leaving the coherent DMA buffer allocated.

Call ena_com_mmio_reg_read_request_destroy() in the probe error path
before releasing the remaining device resources.

This issue was found by manual code inspection.

Fixes: 1738cd3ed3 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Link: https://patch.msgid.link/20260921154202.471662-3-lgs201920130244@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:57:55 -07:00
Guangshuo Li
0958ea4355 net: ena: fix PHC cleanup on probe failure
ena_probe() initializes the PHC as part of ena_device_init(), but the
probe failure path does not destroy it before freeing the PHC private
data.

The normal removal path calls ena_phc_destroy() through
ena_destroy_device() before ena_phc_free(). However, if probe fails
after ena_device_init() succeeds, the error path reaches ena_phc_free()
without unregistering the PTP clock or destroying the device PHC
resources.

Call ena_phc_destroy() in the probe error path before freeing the PHC
private data.

This issue was found by manual code inspection.

Cc: stable@vger.kernel.org tags and describe this as a consistency cleanup
Fixes: e0ea34158e ("net: ena: Add PHC support in the ENA driver")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Cc: stable
Link: https://patch.msgid.link/20260921154202.471662-2-lgs201920130244@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:57:55 -07:00
Jakub Kicinski
a08b39c5d5 Merge branch 'ovs-net-sched-fixes-for-uaf-after-conntrack-extension-realloc'
Ilya Maximets says:

====================
ovs, net/sched: fixes for UAF after conntrack extension realloc

One clean up change plus two fixes for the UAF on helper extension
realloc x 2.  First half for OVS and the second half for the similar
code in act_ct.  This should cover all the known cases of this problem
in these two modules.
====================

Link: https://patch.msgid.link/20260921145655.3167436-1-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:05 -07:00
Ilya Maximets
dad19b59da net/sched: act_ct: fix helper UAF due to extensions realloc
While calling the helpers, a raw pointer to the extensions area is
wired into expectations list:

  -> nf_ct_helper()
   -> helper->help()
    -> nf_ct_expect_related_report()
     -> nf_ct_expect_insert()
      -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)

In case the connection is not confirmed yet, more extensions can be
added afterwards with *_ext_add() calls reallocating the extension
space and leaving the now invalid pointer in the expectations list
that is later accessed while removing the expectation.

Make sure that helpers are called at the end after all the other
extensions are already added.

Note that the helper rejection now leaves the mark and labels set,
but that's not different from how the NAT was handled before or how
the mark and the labels were handled on confirmation failure.  And
there are no atomicity guarantees provided by the API anyway.

Fixes: a21b06e731 ("net: sched: add helper support in act_ct")
Cc: stable@vger.kernel.org
Reported-by: Axel Mierczuk <axel.mierczuk@1password.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20260921145655.3167436-7-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:02 -07:00
Ilya Maximets
00df72e39f net/sched: act_ct: remove 'add_helper' dead code
This variable can only become 'true' when the connection is not
confirmed, but it is only checked when it is confirmed.  So, it can be
treated as being always false and just removed.

Fixes: a21b06e731 ("net: sched: add helper support in act_ct")
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260921145655.3167436-6-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:02 -07:00
Ilya Maximets
f85009dfcd net/sched: act_ct: avoid modifying shared unconfirmed ct entry
In a case where skb with an unconfirmed ct entry gets cloned, we may
end up processing both again but with different sets of extensions.

The series of events:

 1. The first clone wants to commit and runs the helpers wiring up
    the extension pointer into the expectation list.
 2. Then it looses the confirmation keeping the entry unconfirmed.
 3. Second clone now wants to commit labels or run NAT and adds the
    new extension for that breaking the pointer in the expectation
    list causing UAF on the destruction path later.

While this is possible to trigger, there should be no practical
network pipeline where we need to process both clones without
modifications in the same zone.  So, let's just reset the entry in
case for some reason we got an skb with a shared one.  This doesn't
affect any known use cases, but avoids any potential problems with
sharing and modification of the unconfirmed ct entry.

Unlike openvswitch module, act_ct allows for NAT without commit.
Changing that would be a uAPI break.  So, act_ct needs to reset on NAT
regardless of the commit flag to avoid reallocation of the extension
space.  This, however, doesn't really change the picture for sensible
networking cases as there should be no need to run the same packet
twice (before and after the clone) through conntrack without packet
header or zone changes and without commit.

The fixes tag points to the introduction of helpers, since that's the
main UAF trigger for the sharing.

Fixes: a21b06e731 ("net: sched: add helper support in act_ct")
Cc: stable@vger.kernel.org
Reported-by: Axel Mierczuk <axel.mierczuk@1password.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20260921145655.3167436-5-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:02 -07:00
Ilya Maximets
1a4151e6be net: openvswitch: conntrack: fix helper UAF due to extensions realloc
While calling the helpers, a raw pointer to the extensions area is
wired into expectations list:

  -> nf_ct_helper()
   -> helper->help()
    -> nf_ct_expect_related_report()
     -> nf_ct_expect_insert()
      -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations)

In case the connection is not confirmed yet, more extensions can be
added afterwards with *_ext_add() calls reallocating the extension
space and leaving the now invalid pointer in the expectations list
that is later accessed while removing the expectation.

Make sure that helpers are called at the end after all the other
extensions are already added.

Note that the helper rejection now leaves the mark and labels set,
but that's not different from how the NAT was handled before or how
the mark and the labels were handled on confirmation failure.  And
there are no atomicity guarantees provided by the API anyway.

Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Cc: stable@vger.kernel.org
Reported-by: Axel Mierczuk <axel.mierczuk@1password.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20260921145655.3167436-4-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:01 -07:00
Ilya Maximets
5e6c14dd42 net: openvswitch: conntrack: remove 'add_helper' dead code
This variable can only become 'true' when the connection is not
confirmed, but it is only checked when it is confirmed.  So, it can be
treated as being always false and just removed.

Fixes: 3c1860543f ("openvswitch: add nf_ct_is_confirmed check before assigning the helper")
Cc: stable@vger.kernel.org
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20260921145655.3167436-3-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:01 -07:00
Ilya Maximets
26b2bd70d2 net: openvswitch: conntrack: avoid modifying shared unconfirmed ct entry
In a case where skb with an unconfirmed ct entry gets cloned, we may
end up committing both but with different sets of extensions.

The series of events:

 1. The first clone wants to commit and runs the helpers wiring up
    the extension pointer into the expectation list.
 2. Then it looses the confirmation keeping the entry unconfirmed.
 3. Second clone now wants to commit labels and adds the new extension
    for that breaking the pointer in the expectation list causing
    UAF on the destruction path later.

While this is possible to trigger, there should be no practical
network pipeline where committing both clones without modifications
into the same zone is needed.  So, let's just reset the entry in case
for some reason we got an skb with a shared one during commit.  This
doesn't affect any known use cases, but avoids any potential problems
with sharing and modification of the unconfirmed ct entry.

The fixes tag points to the introduction of helpers, since that's the
main UAF trigger for the sharing.

Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Cc: stable@vger.kernel.org
Reported-by: Axel Mierczuk <axel.mierczuk@1password.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Link: https://patch.msgid.link/20260921145655.3167436-2-i.maximets@ovn.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:56:01 -07:00
Jakub Kicinski
33a61f0923 Included fixes:
* add selftest coverage for peer VPN address validation
 * reject multicast, broadcast and loopback peer VPN addresses, which
   can never identify a peer
 * reject MP peers left with no usable VPN address, as they can never
   be selected for TX
 * reject duplicate peer VPN addresses, which made peer lookup return
   an arbitrary peer
 * fix stale entry left in the VPN address hashtable when an address
   is cleared
 * fix torn IPv6 address read on lockless TX when the unusable local
   source is cleared in place
 * fix torn IPv6 address read on lockless TX when a new local endpoint
   is learned in place
 * fix dst cache being populated with a route resolved from an already
   replaced bind
 * fix stale route being reused after the socket mark or UDP source
   port changed
 * fix bogus validation of an unspecified local source address, which
   must instead be left to route source autoselection
 * fix IPv6 link-local peer endpoints losing their scope id when
   configured via netlink, breaking route lookup
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Merge tag 'ovpn-net-20260921' of https://github.com/OpenVPN/ovpn-net-next

Antonio Quartulli says:

====================
Included fixes:
* add selftest coverage for peer VPN address validation
* reject multicast, broadcast and loopback peer VPN addresses, which
  can never identify a peer
* reject MP peers left with no usable VPN address, as they can never
  be selected for TX
* reject duplicate peer VPN addresses, which made peer lookup return
  an arbitrary peer
* fix stale entry left in the VPN address hashtable when an address
  is cleared
* fix torn IPv6 address read on lockless TX when the unusable local
  source is cleared in place
* fix torn IPv6 address read on lockless TX when a new local endpoint
  is learned in place
* fix dst cache being populated with a route resolved from an already
  replaced bind
* fix stale route being reused after the socket mark or UDP source
  port changed
* fix bogus validation of an unspecified local source address, which
  must instead be left to route source autoselection
* fix IPv6 link-local peer endpoints losing their scope id when
  configured via netlink, breaking route lookup

* tag 'ovpn-net-20260921' of https://github.com/OpenVPN/ovpn-net-next:
  selftests: ovpn: validate peer VPN addresses
  ovpn: reject invalid peer VPN addresses
  ovpn: reject multipeer peers without VPN addresses
  ovpn: reject duplicate peer VPN addresses
  ovpn: always unhash old VPN addresses before rehashing
  ovpn: replace bind when clearing stale local source
  ovpn: replace bind when learning local endpoint
  ovpn: validate peer state before caching UDP dst
  ovpn: track UDP socket route key for peer dst cache
  ovpn: skip UDP source validation for unspecified addresses
  ovpn: preserve IPv6 scope id for netlink peer endpoints
====================

Link: https://patch.msgid.link/20260921102215.3599702-1-antonio@openvpn.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:50:49 -07:00
Jiawen Wu
3173cba117 net: libwx: fix races in Tx timestamp handling
wx->ptp_tx_skb is shared between the Tx path, the PTP auxiliary
worker and the timestamp cleanup paths. The
WX_STATE_PTP_TX_IN_PROGRESS bit prevents multiple Tx paths from
submitting timestamp requests, but does not serialize the worker
against cleanup.

As a result, wx_ptp_clear_tx_timestamp() can free an skb after
wx_ptp_tx_hwtstamp_work() has obtained its pointer. The worker may
then pass the freed skb to skb_tstamp_tx() and release the same
reference again.

The cleanup path may also clear the in-progress bit while the worker
is still processing the old skb. This allows the Tx path to publish a
new skb which the worker can subsequently overwrite with NULL,
leaking its reference.

Add a dedicated spinlock to protect publication and consumption of
the Tx timestamp skb. Detach the skb and clear the in-progress bit
while holding the lock, then deliver the timestamp and release the skb
after dropping it. Use the same locked cleanup in the quiesce path,
but keep the detach there free of register accesses: quiesce runs
during PCIe error recovery, where MMIO is not reliable, and it
deliberately did not touch the device before. The lock is taken with
interrupts disabled, because netpoll can call ndo_start_xmit() with
hard interrupts already off.

When handling a Tx DMA mapping failure, keep the transmit path
reference until after comparing the skb under the lock. This prevents
skb address reuse from making the error path mistake a newer timestamp
request for the failed one.

Fixes: 06e75161b9 ("net: wangxun: Add support for PTP clock")
Reported-by: Sashiko <sashiko-bot@kernel.org>
Link: https://netdev-ai.bots.linux.dev/sashiko/#/patchset/6C7EC12D69217315%2B20260818074721.45536-1-jiawenwu%40trustnetic.com
Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Link: https://patch.msgid.link/77431AF9A0E369F3+20260921071549.1141804-1-jiawenwu@trustnetic.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:40:29 -07:00
Aleksei Sviridkin
a940003f44 net: phylink: record the PHY only once bringup cannot fail
phylink_bringup_phy() stores the PHY in pl->phydev before its last
fallible step: on a MAC whose phylink ops implement LPI,
phy_eee_rx_clock_stop() can fail with a real MDIO error. The callers
unwind with phy_detach(), which knows nothing about pl->phydev, so a
pointer to a PHY that is no longer attached outlives the failed
connect.

What that costs depends on how the caller got here.
phylink_connect_phy() goes through phylink_attach_phy(), which refuses
to attach while pl->phydev is set, turning a transient MDIO error into
a permanent -EBUSY. The SFP path is worse than that: sfp_sm_probe_phy()
answers the failure with phy_device_remove() and phy_device_free(), and
it assigns sfp->mod_phy only past that error return, so nothing clears
pl->phydev and it is left pointing at a freed phy_device that
phylink_resolve() and the ethtool helpers go on reading.
phylink_fwnode_phy_connect() has no such check, so a later connect
overwrites the stale pointer and hides the problem. A disconnect does
not: phylink_disconnect_phy() hands that pointer to phy_disconnect(),
and the second phy_detach() on the same PHY drops references the first
one already released.

Found while making a DSA port survive a PHY whose driver arrives after
the switch probes: keeping the port across a failed connect and
retrying is what makes this window reachable.

Publish the pointer after the last call that can fail instead of
unwinding it afterwards. Nothing between the two points reads
pl->phydev, and the registration that follows cannot fail:
phy_request_interrupt() falls back to polling on its own. The PHY-side
state keeps the order it had, so no MDIO operation moves relative to
another.

Fixes: 03abf2a7c6 ("net: phylink: add EEE management")
Signed-off-by: Aleksei Sviridkin <f@lex.la>
Link: https://patch.msgid.link/20260920222044.1752860-1-f@lex.la
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2026-09-24 09:36:05 -07:00