linux-stable.git/drivers/net, branch v7.1.9

veth: fix skb length accounting after XDP frag adjustment

2026-08-19T16:20:29+00:00

commit cb6379feaaff11c4e1e79c26c745ffa23182768a upstream.

veth exposes non-linear skb fragments through an xdp_buff. If an XDP
program adjusts the fragment area, veth_xdp_rcv_skb() copies
xdp_frags_size back to skb->data_len but leaves skb->len containing the
old fragment contribution.

After a fragment shrink, this makes skb_headlen() larger than the actual
linear area. In the reproduced UDP receive path, __skb_datagram_iter()
copied 1024 bytes past the actual linear tail to userspace, starting at
struct skb_shared_info. The copied bytes included the affected skb's
nr_frags, xdp_frags_size, and a kernel pointer from
skb_shinfo(skb)->frags[0]. Real packet data was displaced by the same
amount and truncated at the end.

Subtract the old data_len before replacing it and add the new data_len
afterwards, keeping skb->len and skb->data_len synchronized.

Additionally, bpf_xdp_pull_data() can advance data_end while leaving
frags present. The skb is then still non-linear, so the old
__skb_put(skb, off) triggers SKB_LINEAR_ASSERT().

Use skb_set_tail_pointer() and update skb->len explicitly instead,
following bpf_prog_run_generic_xdp(). Unlike __skb_put(),
skb_set_tail_pointer() does not require a linear skb.

A 60000-byte UDP datagram on a veth pair with MTU 64000 was shortened by
1024 bytes from its fragment area. Before the fix, all 10 runs produced
corrupted payloads. After the fix, all 10 runs matched the expected
payload exactly. A forced-tailroom reproducer also exercises
bpf_xdp_pull_data() with frags still present; the old code triggers
SKB_LINEAR_ASSERT(), while this fix passes 10/10 runs.

Fixes: 718a18a0c8a6 ("veth: Rework veth_xdp_rcv_skb in order to accept non-linear skb")
Cc: stable@vger.kernel.org
Reported-by: Mohsin Bashir 
Link: https://lore.kernel.org/bpf/80687d9c-9c27-494c-b3f2-efd0230b1895@gmail.com/
Suggested-by: Lorenzo Bianconi 
Acked-by: Lorenzo Bianconi 
Signed-off-by: Sun Jian 
Link: https://patch.msgid.link/20260804054040.613675-3-sun.jian.kdev@gmail.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

vxlan: do not arm the ageing timer on a device that is down

2026-08-19T16:20:29+00:00

commit b37971686ec59fb027fa4910ba16805e68fddb97 upstream.

vxlan_changelink() arms vxlan->age_timer whenever the requested ageing
interval differs from the configured one:

	if (conf.age_interval != vxlan->cfg.age_interval)
		mod_timer(&vxlan->age_timer, jiffies);

There is no netif_running() test, so the timer is armed even on a device
that was never brought up.  The only synchronous cancel in the driver is
the timer_delete_sync() in vxlan_stop(), which is .ndo_stop.
netif_close_many() drops devices without IFF_UP before
__dev_close_many() runs, so that cancel is skipped for such a device.

vxlan_setup() sets dev->needs_free_netdev = true and age_timer is a
member of struct vxlan_dev, so free_netdev() releases the allocation the
timer lives in while it is still queued on a timer_base.
expire_timers() unlinks the entry before it loads timer->function, so
the timer core writes through the freed object's list pointers:

  BUG: KASAN: slab-use-after-free in __run_timers+0x208/0x654
  Write of size 8 at addr ffff00001adace68 by task true/192
   __asan_store8+0x84/0xac
   __run_timers+0x208/0x654
   run_timer_softirq+0x154/0x18c
  Allocated by task 189:
   alloc_netdev_mqs+0x64/0x720
   rtnl_create_link+0x4ac/0x520
   rtnl_newlink+0x758/0xd00
  Freed by task 191:
   netdev_release+0x40/0x58
   netdev_run_todo+0x4a4/0x8c0
   rtnl_dellink+0x200/0x4e8

The rtnl operations involved are netns-scoped, so an unprivileged user
can perform them in a new user and network namespace.

Arming the timer on a down device never had an effect: vxlan_cleanup()
returns early on !netif_running(), and vxlan_open() arms the timer for
any non-zero interval once the device is brought up.  Add the missing
test.

Discovered by XBOW, triaged by Baul Lee 

Fixes: 40051c4dcad5 ("vxlan: Allow changing ageing time")
Cc: stable@vger.kernel.org
Signed-off-by: Baul Lee 
Reviewed-by: Ido Schimmel 
Link: https://patch.msgid.link/20260809111829.78834-1-baul.lee@xbow.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

net: atlantic: free RX pages of consumed but not refilled buffers

2026-08-19T16:20:28+00:00

commit e8e7471ef686b6c002218fee9671cc61992ae01a upstream.

aq_ring_rx_deinit() only walks [sw_head, sw_tail), the region posted to
hardware. Since the page reuse strategy was added, a cleaned RX buffer
keeps its page (and its DMA mapping) in the ring for reuse, and refill
is batched: aq_ring_rx_fill() returns early until AQ_CFG_RX_REFILL_THRES
slots are free. Slots that were consumed but not yet reposted therefore
sit in the complementary [sw_tail, sw_head) gap with a live page, and
the deinit walk never visits them: up to a refill batch worth of pages
and DMA mappings leak on every interface down.

Walk the whole ring instead and release whatever is still there. Also
bail out if the buffer ring is already gone: a partial
aq_ptp_ring_alloc() failure frees the ring but leaves aq_nic set, so
aq_ptp_ring_deinit() still gets here on the unwind path.

Cc: stable@vger.kernel.org # v5.2+
Fixes: 46f4c29d9de6 ("net: aquantia: optimize rx performance by page reuse strategy")
Reviewed-by: Sukhdeep Singh 
Signed-off-by: Yangyu Chen 
Acked-by: Mina Almasry 
Link: https://patch.msgid.link/tencent_607CBA8237DA438E36B844318B21538DE008@qq.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: atlantic: free stranded TX buffers on ring deinit

2026-08-19T16:20:28+00:00

commit 452636ea5410a96e02ebaaf80b21e3620b98e0dd upstream.

aq_vec_deinit() drains the TX rings with a single aq_ring_tx_clean()
call, which frees at most AQ_CFG_TX_CLEAN_BUDGET (256) descriptors and
stops at hw_head, which no longer moves once aq_vec_stop() has stopped
the hardware and NAPI. Completed descriptors beyond the budget and
everything still posted in [hw_head, sw_tail) keep their skb or
xdp_frame when the interface goes down: aq_vec_ring_free() then frees
the buffer ring and the references are lost for good.

Today this is a silent memory leak on every interface down under
TX/XDP_TX load. With the conversion of the RX path to page_pool posted
for net-next it becomes much more visible: XDP_TX frames carry fragment
references on the RX ring's page_pool, so a single stranded frame keeps
the pool's inflight count above zero forever. page_pool_destroy() then
never completes, the pool is leaked together with its pages, and
"page_pool_release_retry() stalled pool shutdown" is warned every 60
seconds from that point on, on every ifdown, XDP detach or ring resize
under XDP_TX load.

Bring back aq_ring_tx_deinit() as it was before the removal and use it
for teardown again, with one extension: TX rings can hold xdp_frames
nowadays, so release those too. They are returned with
xdp_return_frame() since this runs in process context.

Fixes: eb36bedf28be ("net: aquantia: remove function aq_ring_tx_deinit")
Cc: stable@vger.kernel.org # v4.11+
Reviewed-by: Sukhdeep Singh 
Signed-off-by: Yangyu Chen 
Acked-by: Mina Almasry 
Link: https://patch.msgid.link/tencent_EEDC35FAF2750A3A6A0B39BAE0E2C484860A@qq.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

NTB: ntb_netdev: Preserve RX queue depth on allocation failure

2026-08-19T16:20:28+00:00

commit d2121faf133ac3bf9531b53a7e21273649a08517 upstream.

ntb_netdev_rx_handler() hands the received skb to the network stack
before allocating its replacement. If the allocation fails, nothing is
reposted. Every failure therefore takes one buffer out of the RX queue
while the interface remains up, and enough failures eventually stall
reception.

A retry path could refill the queue later, but ntb_netdev has none.
Allocate the replacement first instead. If that fails, drop the packet
and repost the same skb. This keeps the queue full and lets packet
delivery resume as soon as memory is available again.

Fixes: 548c237c0a99 ("net: Add support for NTB virtual ethernet device")
Cc: stable@vger.kernel.org
Signed-off-by: Koichiro Den 
Reviewed-by: Dave Jiang 
Link: https://patch.msgid.link/20260806032537.3526498-1-den@valinux.co.jp
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

net: phy: mediatek: fix TX blink masks using the RX bits

2026-08-19T16:20:27+00:00

commit f684c514f7965385dae21f2535f99938e73ec1af upstream.

MTK_GPHY_LED_TX_BLINK_SET and MTK_2P5GPHY_LED_TX_BLINK_SET are built
from the RX blink bits instead of the TX ones, so both TX masks are
identical to their RX counterparts. The TX bits they should be using,
MTK_PHY_LED_BLINK_{10,100,1000,2500}TX, are otherwise only referenced
by the per-speed branch of mtk_phy_led_hw_ctrl_set().

A TX trigger selected without a link trigger therefore programs the RX
blink bits, and the LED blinks on received traffic. The masks are also
used to decode the blink register in mtk_phy_led_hw_ctrl_get(), which
as a result cannot tell the two triggers apart: an RX-only
configuration reads back as RX and TX, and a TX-only configuration
reads back as neither.

Fixes: 7f9c320c98db ("net: phy: mediatek: Move LED helper functions into mtk phy lib")
Cc: stable@vger.kernel.org
Signed-off-by: Ahmed Naseef 
Reviewed-by: Andrew Lunn 
Link: https://patch.msgid.link/20260804113511.3371248-1-naseefkm@gmail.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

igc: fix netdev not re-attached after resume if interface is down

2026-08-19T16:20:24+00:00

commit b0ce5fd9fabe7c79463cf4602217d4dfeff5b1fd upstream.

__igc_resume() calls netif_device_attach() only inside the
netif_running() branch, so an interface that was down during suspend
is never re-attached on resume. It then stays in the not-present state
that __igc_shutdown() set via netif_device_detach(): ethtool reports
ENODEV and every attempt to bring the interface up fails the
netif_device_present() check in __dev_open() with -ENODEV, silently,
since __igc_resume() returns 0. Only reloading the driver recovers the
device.

This is easy to hit in practice because NetworkManager brings managed
interfaces down before sleep unless Wake-on-LAN is configured, making
the adapter unusable after every suspend/resume cycle with WoL
disabled.

Re-attach the netdev on every successful resume, as igb and e1000e do.

Fixes: 6f31d6b643a3 ("igc: Refactor runtime power management flow")
Cc: stable@vger.kernel.org
Signed-off-by: Philipp David 
Reviewed-by: Aleksandr Loktionov 
Reviewed-by: Dima Ruinskiy 
Signed-off-by: Tony Nguyen 
Link: https://patch.msgid.link/20260804222205.1580328-11-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: octeontx2-pf: Fix UB in shift operation

2026-08-19T16:20:23+00:00

commit 7e2d693af0d4c05bddccb3541a0aabd69f4cb244 upstream.

In function otx2_get_egress_burst_cfg, when the parameter `burst` is
255 and the max mantissa is 255 (0xFFULL), `burst_exp` is set to
`ilog2(255) - 1`, which equals 6.

This results in an unsigned wrap-around when calculating
`(1ULL << (*burst_exp - 7))`, since `*burst_exp - 7` becomes -1,
which makes the shift operand 0xFFFFFFFF. This value is greater than
the width of the left operand.

According to standard 6.5.7 p.3:
"The type of the result is that of the promoted left operand.
If the value of the right operand is negative or is greater than
or equal to the width of the promoted left operand, the behavior
is undefined."

Fix the off-by-one boundary condition.

Add a WARN_ON(*burst_exp < 7) before the else branch as an
explicit safeguard. This ensures that if max_mantissa ever changes
in a way that reintroduces this condition, it will be immediately
caught at runtime rather than silently triggering UB.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: e638a83f167e ("octeontx2-pf: TC_MATCHALL egress ratelimiting offload")
Signed-off-by: Sergey V. Frolov 
Cc: stable@vger.kernel.org
Reviewed-by: Ratheesh Kannoth 
Reviewed-by: Sunil Goutham 
Link: https://patch.msgid.link/20260804120446.1955448-1-Sergey.V.Frolov@kaspersky.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Greg Kroah-Hartman

usbnet: cap max_mtu for drivers without bind callback

2026-08-19T16:20:22+00:00

commit 1505b2cb6ae1c7e8ac0c6e4590a204ffc3ab2b24 upstream.

usbnet_probe() initializes max_mtu to ETH_MAX_MTU and only caps it
inside the if (info->bind) block. Drivers without a bind callback
never enter this block, so max_mtu stays at ETH_MAX_MTU.

QEMU's usb-net device (0x0525/0xa4a2) is claimed by the cdc_subset
driver which has no bind callback. The guest accepts any MTU from DHCP
(e.g. 65520 from passt), leading to TCP segments that exceed the
device's 2048-byte receive buffer and are silently dropped.

Initialize max_mtu to net->mtu at probe time and update it inside
the bind block.

Fixes: f77f0aee4da4 ("net: use core MTU range checking in USB NIC drivers")
Cc: jarod@redhat.com
Cc: stable@vger.kernel.org
Link: https://gitlab.com/qemu-project/qemu/-/issues/3268
Link: https://bugs.passt.top/show_bug.cgi?id=189
Signed-off-by: Laurent Vivier 
Link: https://patch.msgid.link/20260731092711.857684-1-lvivier@redhat.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

net: usb: ipheth: fix carrier_work UAF on disconnect

2026-08-19T16:20:22+00:00

commit fde39b8a521780391fb4e5bda2c0aa4928947f12 upstream.

ipheth_sndbulk_callback() re-arms the carrier-check work on any
non-zero URB status:

	else
		schedule_delayed_work(&dev->carrier_work, 0);

Nothing ties that to the interface being up, so the work can be armed
again after ipheth_close() has already drained it, and stay armed
until the netdev whose private area embeds it is freed.

On unplug with a TX URB in flight, ipheth_disconnect() drains the work
through unregister_netdev() -> ipheth_close() ->
cancel_delayed_work_sync() and only then calls ipheth_kill_urbs().
usb_kill_urb() completes the in-flight TX URB with -ENOENT, so
ipheth_sndbulk_callback() runs after the drain and re-arms
carrier_work.

The same completion also re-arms the work if the interface is only
brought down while a TX URB is in flight, and
ipheth_carrier_check_work() then keeps re-queueing itself once a
second. unregister_netdev() does not call ipheth_close() for an
already-down interface, so nothing drains it on the later unplug
either.

In both cases free_netdev() frees the netdev while carrier_work is
still pending, and ipheth_carrier_check_work() dereferences freed
memory.

Tie the work to the interface state instead of chasing the completion:
disable it in ipheth_close() and enable it in ipheth_open(), so a
schedule_delayed_work() from the URB completion is a no-op whenever
the interface is not up. disable_delayed_work_sync() also waits for a
running instance, so it fully replaces the cancel_delayed_work_sync()
it takes the place of. The work starts out disabled in ipheth_probe()
so the enable/disable counts balance from the first open.

Reproduced under KASAN on linux-next (next-20260731) with dummy_hcd and
raw-gadget standing in for the device, driving the second path above (the
interface is already down, so unregister_netdev() does not call
ipheth_close()): 15 of 15 unpatched boots report a slab-use-after-free in
__run_timers(), freed by ipheth_disconnect() and re-armed from
ipheth_sndbulk_callback() via queue_delayed_work_on(). The
same trigger on a kernel differing only by this patch reports 0 of 15,
and the carrier check still functions across open/close cycles.

The reproducer needs an attached USB device that stops draining bulk OUT,
plus a link down and unplug, driven as root. It is not a privilege
boundary crossing and no exploit primitive was developed.

Found by 0sec (https://0sec.ai).

Fixes: bb1b40c7cb86 ("usbnet: ipheth: prevent TX queue timeouts when device not ready")
Cc: stable@vger.kernel.org
Signed-off-by: Doruk Tan Ozturk 
Link: https://patch.msgid.link/20260802120602.42595-1-doruk@0sec.ai
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman