Paolo Abeni [Tue, 3 Mar 2026 10:56:02 +0000 (11:56 +0100)]
selftests: mptcp: more stable simult_flows tests
By default, the netem qdisc can keep up to 1000 packets under its belly
to deal with the configured rate and delay. The simult flows test-case
simulates very low speed links, to avoid problems due to slow CPUs and
the TCP stack tend to transmit at a slightly higher rate than the
(virtual) link constraints.
All the above causes a relatively large amount of packets being enqueued
in the netem qdiscs - the longer the transfer, the longer the queue -
producing increasingly high TCP RTT samples and consequently increasingly
larger receive buffer size due to DRS.
When the receive buffer size becomes considerably larger than the needed
size, the tests results can flake, i.e. because minimal inaccuracy in the
pacing rate can lead to a single subflow usage towards the end of the
connection for a considerable amount of data.
Address the issue explicitly setting netem limits suitable for the
configured link speeds and unflake all the affected tests.
====================
nfc: fix leaks and races surfaced by NIPA
I recently added the nci test to NIPA. Somewhat surprisingly it runs
without much settup but hits kmemleaks fairly often. Fix a handful of
issues to make the test pass in a stable way.
====================
Jakub Kicinski [Tue, 3 Mar 2026 16:23:45 +0000 (08:23 -0800)]
nfc: rawsock: cancel tx_work before socket teardown
In rawsock_release(), cancel any pending tx_work and purge the write
queue before orphaning the socket. rawsock_tx_work runs on the system
workqueue and calls nfc_data_exchange which dereferences the NCI
device. Without synchronization, tx_work can race with socket and
device teardown when a process is killed (e.g. by SIGKILL), leading
to use-after-free or leaked references.
Set SEND_SHUTDOWN first so that if tx_work is already running it will
see the flag and skip transmitting, then use cancel_work_sync to wait
for any in-progress execution to finish, and finally purge any
remaining queued skbs.
Jakub Kicinski [Tue, 3 Mar 2026 16:23:44 +0000 (08:23 -0800)]
nfc: nci: clear NCI_DATA_EXCHANGE before calling completion callback
Move clear_bit(NCI_DATA_EXCHANGE) before invoking the data exchange
callback in nci_data_exchange_complete().
The callback (e.g. rawsock_data_exchange_complete) may immediately
schedule another data exchange via schedule_work(tx_work). On a
multi-CPU system, tx_work can run and reach nci_transceive() before
the current nci_data_exchange_complete() clears the flag, causing
test_and_set_bit(NCI_DATA_EXCHANGE) to return -EBUSY and the new
transfer to fail.
This causes intermittent flakes in nci/nci_dev in NIPA:
# # RUN NCI.NCI1_0.t4t_tag_read ...
# # t4t_tag_read: Test terminated by timeout
# # FAIL NCI.NCI1_0.t4t_tag_read
# not ok 3 NCI.NCI1_0.t4t_tag_read
Jakub Kicinski [Tue, 3 Mar 2026 16:23:43 +0000 (08:23 -0800)]
nfc: nci: complete pending data exchange on device close
In nci_close_device(), complete any pending data exchange before
closing. The data exchange callback (e.g.
rawsock_data_exchange_complete) holds a socket reference.
Jakub Kicinski [Tue, 3 Mar 2026 16:23:41 +0000 (08:23 -0800)]
nfc: nci: free skb on nci_transceive early error paths
nci_transceive() takes ownership of the skb passed by the caller,
but the -EPROTO, -EINVAL, and -EBUSY error paths return without
freeing it.
Due to issues clearing NCI_DATA_EXCHANGE fixed by subsequent changes
the nci/nci_dev selftest hits the error path occasionally in NIPA,
and kmemleak detects leaks:
Bobby Eshleman [Tue, 3 Mar 2026 00:32:56 +0000 (16:32 -0800)]
net: devmem: use READ_ONCE/WRITE_ONCE on binding->dev
binding->dev is protected on the write-side in
mp_dmabuf_devmem_uninstall() against concurrent writes, but due to the
concurrent bare reads in net_devmem_get_binding() and
validate_xmit_unreadable_skb() it should be wrapped in a
READ_ONCE/WRITE_ONCE pair to make sure no compiler optimizations play
with the underlying register in unforeseen ways.
Doesn't present a critical bug because the known compiler optimizations
don't result in bad behavior. There is no tearing on u64, and load
omissions/invented loads would only break if additional binding->dev
references were inlined together (they aren't right now).
This just more strictly follows the linux memory model (i.e.,
"Lock-Protected Writes With Lockless Reads" in
tools/memory-model/Documentation/access-marking.txt).
Koichiro Den [Sat, 28 Feb 2026 14:53:07 +0000 (23:53 +0900)]
net: sched: avoid qdisc_reset_all_tx_gt() vs dequeue race for lockless qdiscs
When shrinking the number of real tx queues,
netif_set_real_num_tx_queues() calls qdisc_reset_all_tx_gt() to flush
qdiscs for queues which will no longer be used.
qdisc_reset_all_tx_gt() currently serializes qdisc_reset() with
qdisc_lock(). However, for lockless qdiscs, the dequeue path is
serialized by qdisc_run_begin/end() using qdisc->seqlock instead, so
qdisc_reset() can run concurrently with __qdisc_run() and free skbs
while they are still being dequeued, leading to UAF.
This can easily be reproduced on e.g. virtio-net by imposing heavy
traffic while frequently changing the number of queue pairs:
Allocated by task 1270 on cpu 5 at 44.558414s:
...
alloc_skb_with_frags+0x84/0x7c0
sock_alloc_send_pskb+0x69a/0x830
__ip_append_data+0x1b86/0x48c0
ip_make_skb+0x1e8/0x2b0
udp_sendmsg+0x13a6/0x1fc0
...
Freed by task 1306 on cpu 3 at 44.558445s:
...
kmem_cache_free+0x117/0x5e0
pfifo_fast_reset+0x14d/0x580
qdisc_reset+0x9e/0x5f0
netif_set_real_num_tx_queues+0x303/0x840
virtnet_set_channels+0x1bf/0x260 [virtio_net]
ethnl_set_channels+0x684/0xae0
ethnl_default_set_doit+0x31a/0x890
...
Serialize qdisc_reset_all_tx_gt() against the lockless dequeue path by
taking qdisc->seqlock for TCQ_F_NOLOCK qdiscs, matching the
serialization model already used by dev_reset_queue().
Additionally clear QDISC_STATE_NON_EMPTY after reset so the qdisc state
reflects an empty queue, avoiding needless re-scheduling.
Jakub Kicinski [Thu, 5 Mar 2026 00:47:45 +0000 (16:47 -0800)]
Merge tag 'linux-can-fixes-for-7.0-20260302' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can
Marc Kleine-Budde says:
====================
pull-request: can 2026-03-02
The first 2 patches are by Oliver Hartkopp. The first fixes the
locking for CAN Broadcast Manager op runtime updates, the second fixes
the packet statisctics for the CAN dummy driver.
Alban Bedel's patch fixes a potential problem in the error path of the
mcp251x's ndo_open callback.
A patch by Ziyi Guo add USB endpoint type validation to the esd_usb
driver.
The next 6 patches are by Greg Kroah-Hartman and fix URB data parsing
for the ems_usb and ucan driver, fix URB anchoring in the etas_es58x,
and in the f81604 driver fix URB data parsing, add URB error handling
and fix URB anchoring.
A patch by me targets the gs_usb driver and fixes interoperability
with the CANable-2.5 firmware by always configuring the bit rate
before starting the device.
The last patch is by Frank Li and fixes a CHECK_DTBS warning for the
nxp,sja1000 dt-binding.
* tag 'linux-can-fixes-for-7.0-20260302' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can:
dt-bindings: net: can: nxp,sja1000: add reference to mc-peripheral-props.yaml
can: gs_usb: gs_can_open(): always configure bitrates before starting device
can: usb: f81604: correctly anchor the urb in the read bulk callback
can: usb: f81604: handle bulk write errors properly
can: usb: f81604: handle short interrupt urb messages properly
can: usb: etas_es58x: correctly anchor the urb in the read bulk callback
can: ucan: Fix infinite loop from zero-length messages
can: ems_usb: ems_usb_read_bulk_callback(): check the proper length of a message
can: esd_usb: add endpoint type validation
can: mcp251x: fix deadlock in error path of mcp251x_open
can: dummy_can: dummy_can_init(): fix packet statistics
can: bcm: fix locking for bcm_op runtime updates
====================
Jakub Kicinski [Wed, 4 Mar 2026 23:29:56 +0000 (15:29 -0800)]
Merge tag 'wireless-2026-03-04' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless
Johannes Berg says:
====================
Some more fixes:
- mt76 gets three almost identical new length checks
- cw1200 & ti: locking fixes
- mac80211 has a fix for the recent EML frame handling
- rsi driver no longer oddly responds to config, which
had triggered a warning in mac80211
- ath12k has two fixes for station statistics handling
* tag 'wireless-2026-03-04' of https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless:
wifi: mt76: Fix possible oob access in mt76_connac2_mac_write_txwi_80211()
wifi: mt76: mt7925: Fix possible oob access in mt7925_mac_write_txwi_80211()
wifi: mt76: mt7996: Fix possible oob access in mt7996_mac_write_txwi_80211()
wifi: wlcore: Fix a locking bug
wifi: cw1200: Fix locking in error paths
wifi: mac80211: fix missing ieee80211_eml_params member initialization
wifi: rsi: Don't default to -EOPNOTSUPP in rsi_mac80211_config
wifi: ath12k: fix station lookup failure when disconnecting from AP
wifi: ath12k: use correct pdev id when requesting firmware stats
====================
Naveen Anandhan [Sat, 28 Feb 2026 07:47:35 +0000 (13:17 +0530)]
selftests: tc-testing: fix list_categories() crash on list type
list_categories() builds a set directly from the 'category'
field of each test case. Since 'category' is a list,
set(map(...)) attempts to insert lists into a set, which
raises:
TypeError: unhashable type: 'list'
Flatten category lists and collect unique category names
using set.update() instead.
Signed-off-by: Naveen Anandhan <mr.navi8680@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Mark the skge and sky2 drivers as orphan.
I no longer have any Marvell/SysKonnect boards to test with and
mail to Mirko Lindner bounced because Marvell sold off that divsion.
Raju Rangoju [Mon, 2 Mar 2026 04:21:24 +0000 (09:51 +0530)]
amd-xgbe: fix sleep while atomic on suspend/resume
The xgbe_powerdown() and xgbe_powerup() functions use spinlocks
(spin_lock_irqsave) while calling functions that may sleep:
- napi_disable() can sleep waiting for NAPI polling to complete
- flush_workqueue() can sleep waiting for pending work items
This causes a "BUG: scheduling while atomic" error during suspend/resume
cycles on systems using the AMD XGBE Ethernet controller.
The spinlock protection in these functions is unnecessary as these
functions are called from suspend/resume paths which are already serialized
by the PM core
Fix this by removing the spinlock. Since only code that takes this lock
is xgbe_powerdown() and xgbe_powerup(), remove it completely.
Breno Leitao [Mon, 2 Mar 2026 11:40:46 +0000 (03:40 -0800)]
netconsole: fix sysdata_release_enabled_show checking wrong flag
sysdata_release_enabled_show() checks SYSDATA_TASKNAME instead of
SYSDATA_RELEASE, causing the configfs release_enabled attribute to
reflect the taskname feature state rather than the release feature
state. This is a copy-paste error from the adjacent
sysdata_taskname_enabled_show() function.
The corresponding _store function already uses the correct
SYSDATA_RELEASE flag.
Yung Chih Su [Mon, 2 Mar 2026 06:02:47 +0000 (14:02 +0800)]
net: ipv4: fix ARM64 alignment fault in multipath hash seed
`struct sysctl_fib_multipath_hash_seed` contains two u32 fields
(user_seed and mp_seed), making it an 8-byte structure with a 4-byte
alignment requirement.
In `fib_multipath_hash_from_keys()`, the code evaluates the entire
struct atomically via `READ_ONCE()`:
While this silently works on GCC by falling back to unaligned regular
loads which the ARM64 kernel tolerates, it causes a fatal kernel panic
when compiled with Clang and LTO enabled.
Commit e35123d83ee3 ("arm64: lto: Strengthen READ_ONCE() to acquire
when CONFIG_LTO=y") strengthens `READ_ONCE()` to use Load-Acquire
instructions (`ldar` / `ldapr`) to prevent compiler reordering bugs
under Clang LTO. Since the macro evaluates the full 8-byte struct,
Clang emits a 64-bit `ldar` instruction. ARM64 architecture strictly
requires `ldar` to be naturally aligned, thus executing it on a 4-byte
aligned address triggers a strict Alignment Fault (FSC = 0x21).
Fix the read side by moving the `READ_ONCE()` directly to the `u32`
member, which emits a safe 32-bit `ldar Wn`.
Furthermore, Eric Dumazet pointed out that `WRITE_ONCE()` on the entire
struct in `proc_fib_multipath_hash_set_seed()` is also flawed. Analysis
shows that Clang splits this 8-byte write into two separate 32-bit
`str` instructions. While this avoids an alignment fault, it destroys
atomicity and exposes a tear-write vulnerability. Fix this by
explicitly splitting the write into two 32-bit `WRITE_ONCE()`
operations.
Finally, add the missing `READ_ONCE()` when reading `user_seed` in
`proc_fib_multipath_hash_seed()` to ensure proper pairing and
concurrency safety.
Fixes: 4ee2a8cace3f ("net: ipv4: Add a sysctl to set multipath hash seed") Signed-off-by: Yung Chih Su <yuuchihsu@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260302060247.7066-1-yuuchihsu@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jakub Kicinski [Sun, 1 Mar 2026 19:45:48 +0000 (11:45 -0800)]
ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu()
l3mdev_master_dev_rcu() can return NULL when the slave device is being
un-slaved from a VRF. All other callers deal with this, but we lost
the fallback to loopback in ip6_rt_pcpu_alloc() -> ip6_rt_get_dev_rcu()
with commit 4832c30d5458 ("net: ipv6: put host and anycast routes on
device with address").
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
RIP: 0010:ip6_rt_pcpu_alloc (net/ipv6/route.c:1418)
Call Trace:
ip6_pol_route (net/ipv6/route.c:2318)
fib6_rule_lookup (net/ipv6/fib6_rules.c:115)
ip6_route_output_flags (net/ipv6/route.c:2607)
vrf_process_v6_outbound (drivers/net/vrf.c:437)
I was tempted to rework the un-slaving code to clear the flag first
and insert synchronize_rcu() before we remove the upper. But looks like
the explicit fallback to loopback_dev is an established pattern.
And I guess avoiding the synchronize_rcu() is nice, too.
YiFei Zhu [Fri, 27 Feb 2026 22:19:37 +0000 (22:19 +0000)]
net: Fix rcu_tasks stall in threaded busypoll
I was debugging a NIC driver when I noticed that when I enable
threaded busypoll, bpftrace hangs when starting up. dmesg showed:
rcu_tasks_wait_gp: rcu_tasks grace period number 85 (since boot) is 10658 jiffies old.
rcu_tasks_wait_gp: rcu_tasks grace period number 85 (since boot) is 40793 jiffies old.
rcu_tasks_wait_gp: rcu_tasks grace period number 85 (since boot) is 131273 jiffies old.
rcu_tasks_wait_gp: rcu_tasks grace period number 85 (since boot) is 402058 jiffies old.
INFO: rcu_tasks detected stalls on tasks: 00000000769f52cd: .N nvcsw: 2/2 holdout: 1 idle_cpu: -1/64
task:napi/eth2-8265 state:R running task stack:0 pid:48300 tgid:48300 ppid:2 task_flags:0x208040 flags:0x00004000
Call Trace:
<TASK>
? napi_threaded_poll_loop+0x27c/0x2c0
? __pfx_napi_threaded_poll+0x10/0x10
? napi_threaded_poll+0x26/0x80
? kthread+0xfa/0x240
? __pfx_kthread+0x10/0x10
? ret_from_fork+0x31/0x50
? __pfx_kthread+0x10/0x10
? ret_from_fork_asm+0x1a/0x30
</TASK>
The cause is that in threaded busypoll, the main loop is in
napi_threaded_poll rather than napi_threaded_poll_loop, where the
latter rarely iterates more than once within its loop. For
rcu_softirq_qs_periodic inside napi_threaded_poll_loop to report its
qs state, the last_qs must be 100ms behind, and this can't happen
because napi_threaded_poll_loop rarely iterates in threaded busypoll,
and each time napi_threaded_poll_loop is called last_qs is reset to
latest jiffies.
This patch changes so that in threaded busypoll, last_qs is saved
in the outer napi_threaded_poll, and whether busy_poll_last_qs
is NULL indicates whether napi_threaded_poll_loop is called for
busypoll. This way last_qs would not reset to latest jiffies on
each invocation of napi_threaded_poll_loop.
Fixes: c18d4b190a46 ("net: Extend NAPI threaded polling to allow kthread based busy polling") Cc: stable@vger.kernel.org Signed-off-by: YiFei Zhu <zhuyifei@google.com> Reviewed-by: Samiullah Khawaja <skhawaja@google.com> Link: https://patch.msgid.link/20260227221937.1060857-1-zhuyifei@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
net/rds: Fix circular locking dependency in rds_tcp_tune
syzbot reported a circular locking dependency in rds_tcp_tune() where
sk_net_refcnt_upgrade() is called while holding the socket lock:
======================================================
WARNING: possible circular locking dependency detected
======================================================
kworker/u10:8/15040 is trying to acquire lock: ffffffff8e9aaf80 (fs_reclaim){+.+.}-{0:0},
at: __kmalloc_cache_noprof+0x4b/0x6f0
but task is already holding lock: ffff88805a3c1ce0 (k-sk_lock-AF_INET6){+.+.}-{0:0},
at: rds_tcp_tune+0xd7/0x930
The issue occurs because sk_net_refcnt_upgrade() performs memory
allocation (via get_net_track() -> ref_tracker_alloc()) while the
socket lock is held, creating a circular dependency with fs_reclaim.
Fix this by moving sk_net_refcnt_upgrade() outside the socket lock
critical section. This is safe because the fields modified by the
sk_net_refcnt_upgrade() call (sk_net_refcnt, ns_tracker) are not
accessed by any concurrent code path at this point.
v2:
- Corrected fixes tag
- check patch line wrap nits
- ai commentary nits
Lorenzo Bianconi [Thu, 26 Feb 2026 19:11:16 +0000 (20:11 +0100)]
wifi: mt76: Fix possible oob access in mt76_connac2_mac_write_txwi_80211()
Check frame length before accessing the mgmt fields in
mt76_connac2_mac_write_txwi_80211 in order to avoid a possible oob
access.
Fixes: 577dbc6c656d ("mt76: mt7915: enable offloading of sequence number assignment") Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Link: https://patch.msgid.link/20260226-mt76-addba-req-oob-access-v1-3-b0f6d1ad4850@kernel.org
[fix check to also cover mgmt->u.action.u.addba_req.capab,
correct Fixes tag] Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Bart Van Assche [Mon, 23 Feb 2026 22:00:24 +0000 (14:00 -0800)]
wifi: cw1200: Fix locking in error paths
cw1200_wow_suspend() must only return with priv->conf_mutex locked if it
returns zero. This mutex must be unlocked if an error is returned. Add
mutex_unlock() calls to the error paths from which that call is missing.
This has been detected by the Clang thread-safety analyzer.
====================
avoid compiler and IQ/OQ reordering
Utilize READ_ONCE and WRITE_ONCE APIs to prevent compiler
optimization and reordering. Ensure IO queue OUT/IN_CNT
registers are flushed. Relocate IQ/OQ IN/OUT_CNTS updates
to occur before NAPI completion, and replace napi_complete
with napi_complete_done.
====================
Vimlesh Kumar [Fri, 27 Feb 2026 09:14:00 +0000 (09:14 +0000)]
octeon_ep_vf: avoid compiler and IQ/OQ reordering
Utilize READ_ONCE and WRITE_ONCE APIs for IO queue Tx/Rx
variable access to prevent compiler optimization and reordering.
Additionally, ensure IO queue OUT/IN_CNT registers are flushed
by performing a read-back after writing.
The compiler could reorder reads/writes to pkts_pending, last_pkt_count,
etc., causing stale values to be used when calculating packets to process
or register updates to send to hardware. The Octeon hardware requires a
read-back after writing to OUT_CNT/IN_CNT registers to ensure the write
has been flushed through any posted write buffers before the interrupt
resend bit is set. Without this, we have observed cases where the hardware
didn't properly update its internal state.
wmb/rmb only provides ordering guarantees but doesn't prevent the compiler
from performing optimizations like caching in registers, load tearing etc.
Vimlesh Kumar [Fri, 27 Feb 2026 09:13:59 +0000 (09:13 +0000)]
octeon_ep_vf: Relocate counter updates before NAPI
Relocate IQ/OQ IN/OUT_CNTS updates to occur before NAPI completion.
Moving the IQ/OQ counter updates before napi_complete_done ensures
1. Counter registers are updated before re-enabling interrupts.
2. Prevents a race where new packets arrive but counters aren't properly
synchronized.
Vimlesh Kumar [Fri, 27 Feb 2026 09:13:58 +0000 (09:13 +0000)]
octeon_ep: avoid compiler and IQ/OQ reordering
Utilize READ_ONCE and WRITE_ONCE APIs for IO queue Tx/Rx
variable access to prevent compiler optimization and reordering.
Additionally, ensure IO queue OUT/IN_CNT registers are flushed
by performing a read-back after writing.
The compiler could reorder reads/writes to pkts_pending, last_pkt_count,
etc., causing stale values to be used when calculating packets to process
or register updates to send to hardware. The Octeon hardware requires a
read-back after writing to OUT_CNT/IN_CNT registers to ensure the write
has been flushed through any posted write buffers before the interrupt
resend bit is set. Without this, we have observed cases where the hardware
didn't properly update its internal state.
wmb/rmb only provides ordering guarantees but doesn't prevent the compiler
from performing optimizations like caching in registers, load tearing etc.
Vimlesh Kumar [Fri, 27 Feb 2026 09:13:57 +0000 (09:13 +0000)]
octeon_ep: Relocate counter updates before NAPI
Relocate IQ/OQ IN/OUT_CNTS updates to occur before NAPI completion,
and replace napi_complete with napi_complete_done.
Moving the IQ/OQ counter updates before napi_complete_done ensures
1. Counter registers are updated before re-enabling interrupts.
2. Prevents a race where new packets arrive but counters aren't properly
synchronized.
napi_complete_done (vs napi_complete) allows for better
interrupt coalescing.
====================
bonding: fix missing XDP compat check on xmit_hash_policy change
syzkaller reported a bug https://syzkaller.appspot.com/bug?extid=5a287bcdc08104bc3132
When a bond device is in 802.3ad or balance-xor mode, XDP is supported
only when xmit_hash_policy != vlan+srcmac. This constraint is enforced
in bond_option_mode_set() via bond_xdp_check(), which prevents switching
to an XDP-incompatible mode while a program is loaded. However, the
symmetric path -- changing xmit_hash_policy while XDP is loaded -- had
no such guard in bond_option_xmit_hash_policy_set().
This means the following sequence silently creates an inconsistent state:
1. Create a bond in 802.3ad mode with xmit_hash_policy=layer2+3.
2. Attach a native XDP program to the bond.
3. Change xmit_hash_policy to vlan+srcmac (no error, not checked).
Now bond->xdp_prog is set but bond_xdp_check() returns false for the
same device. When the bond is later torn down (e.g. netns deletion),
dev_xdp_uninstall() calls bond_xdp_set(dev, NULL) to remove the
program, which hits the bond_xdp_check() guard and returns -EOPNOTSUPP,
triggering a kernel WARNING:
Beyond the WARNING itself, when dev_xdp_install() fails during
dev_xdp_uninstall(), bond_xdp_set() returns early without calling
bpf_prog_put() on the old program. dev_xdp_uninstall() then releases
only the reference held by dev->xdp_state[], while the reference held
by bond->xdp_prog is never dropped, leaking the struct bpf_prog.
The fix refactors the core logic of bond_xdp_check() into a new helper
__bond_xdp_check_mode(mode, xmit_policy) that takes both parameters
explicitly, avoiding the need to read them from the bond struct.
bond_xdp_check() becomes a thin wrapper around it.
bond_option_xmit_hash_policy_set() then uses __bond_xdp_check_mode()
directly, passing the candidate xmit_policy before it is committed,
mirroring exactly what bond_option_mode_set() already does for mode
changes.
Patch 1 adds the kernel fix.
Patch 2 adds a selftest that reproduces the WARNING by attaching native
XDP to a bond in 802.3ad mode, then attempting to change xmit_hash_policy
to vlan+srcmac -- verifying the change is rejected with the fix applied.
====================
Jiayuan Chen [Thu, 26 Feb 2026 08:03:02 +0000 (16:03 +0800)]
selftests/bpf: add test for xdp_bonding xmit_hash_policy compat
Add a selftest to verify that changing xmit_hash_policy to vlan+srcmac
is rejected when a native XDP program is loaded on a bond in 802.3ad
mode. Without the fix in bond_option_xmit_hash_policy_set(), the change
succeeds silently, creating an inconsistent state that triggers a kernel
WARNING in dev_xdp_uninstall() when the bond is torn down.
The test attaches native XDP to a bond0 (802.3ad, layer2+3), then
attempts to switch xmit_hash_policy to vlan+srcmac and asserts the
operation fails. It also verifies the change succeeds after XDP is
detached, confirming the rejection is specific to the XDP-loaded state.
Jiayuan Chen [Thu, 26 Feb 2026 08:03:01 +0000 (16:03 +0800)]
bpf/bonding: reject vlan+srcmac xmit_hash_policy change when XDP is loaded
bond_option_mode_set() already rejects mode changes that would make a
loaded XDP program incompatible via bond_xdp_check(). However,
bond_option_xmit_hash_policy_set() has no such guard.
For 802.3ad and balance-xor modes, bond_xdp_check() returns false when
xmit_hash_policy is vlan+srcmac, because the 802.1q payload is usually
absent due to hardware offload. This means a user can:
1. Attach a native XDP program to a bond in 802.3ad/balance-xor mode
with a compatible xmit_hash_policy (e.g. layer2+3).
2. Change xmit_hash_policy to vlan+srcmac while XDP remains loaded.
This leaves bond->xdp_prog set but bond_xdp_check() now returning false
for the same device. When the bond is later destroyed, dev_xdp_uninstall()
calls bond_xdp_set(dev, NULL, NULL) to remove the program, which hits
the bond_xdp_check() guard and returns -EOPNOTSUPP, triggering:
Fix this by rejecting xmit_hash_policy changes to vlan+srcmac when an
XDP program is loaded on a bond in 802.3ad or balance-xor mode.
commit 39a0876d595b ("net, bonding: Disallow vlan+srcmac with XDP")
introduced bond_xdp_check() which returns false for 802.3ad/balance-xor
modes when xmit_hash_policy is vlan+srcmac. The check was wired into
bond_xdp_set() to reject XDP attachment with an incompatible policy, but
the symmetric path -- preventing xmit_hash_policy from being changed to an
incompatible value after XDP is already loaded -- was left unguarded in
bond_option_xmit_hash_policy_set().
Note:
commit 094ee6017ea0 ("bonding: check xdp prog when set bond mode")
later added a similar guard to bond_option_mode_set(), but
bond_option_xmit_hash_policy_set() remained unprotected.
Commit 1cc93c48b5d7 ("selftests/net: packetdrill: remove tests for
tcp_rcv_*big") removed the test for the reverted commit 1d2fbaad7cd8
("tcp: stronger sk_rcvbuf checks") but also the one for commit 9ca48d616ed7 ("tcp: do not accept packets beyond window").
Restore the test with the necessary adaptation: expect a delayed ACK
instead of an immediate one, since tcp_can_ingest() does not fail
anymore for the last data packet.
net: dsa: realtek: rtl8365mb: fix rtl8365mb_phy_ocp_write return value
Function rtl8365mb_phy_ocp_write() always returns 0, even when an error
occurs during register access. This patch fixes the return value to
propagate the actual error code from regmap operations.
Frank Li [Thu, 12 Feb 2026 16:30:00 +0000 (11:30 -0500)]
dt-bindings: net: can: nxp,sja1000: add reference to mc-peripheral-props.yaml
Add a reference to mc-peripheral-props.yaml to allow vendor-specific
properties for memory access timings.
Fix below CHECK_DTBS warings:
arch/arm/boot/dts/nxp/imx/imx27-phytec-phycore-rdk.dtb: can@4,0 (nxp,sja1000): Unevaluated properties are not allowed ('fsl,weim-cs-timing' was unexpected)
from schema $id: http://devicetree.org/schemas/net/can/nxp,sja1000.yaml
can: gs_usb: gs_can_open(): always configure bitrates before starting device
So far the driver populated the struct can_priv::do_set_bittiming() and
struct can_priv::fd::do_set_data_bittiming() callbacks.
Before bringing up the interface, user space has to configure the bitrates.
With these callbacks the configuration is directly forwarded into the CAN
hardware. Then the interface can be brought up.
An ifdown-ifup cycle (without changing the bit rates) doesn't re-configure
the bitrates in the CAN hardware. This leads to a problem with the
CANable-2.5 [1] firmware, which resets the configured bit rates during
ifdown.
To fix the problem remove both bit timing callbacks and always configure
the bitrates in the struct net_device_ops::ndo_open() callback.
can: usb: f81604: correctly anchor the urb in the read bulk callback
When submitting an urb, that is using the anchor pattern, it needs to be
anchored before submitting it otherwise it could be leaked if
usb_kill_anchored_urbs() is called. This logic is correctly done
elsewhere in the driver, except in the read bulk callback so do that
here also.
Cc: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: Vincent Mailhol <mailhol@kernel.org> Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/2026022334-starlight-scaling-2cea@gregkh Fixes: 88da17436973 ("can: usb: f81604: add Fintek F81604 support") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
If a write urb fails then more needs to be done other than just logging
the message, otherwise the transmission could be stalled. Properly
increment the error counters and wake up the queues so that data will
continue to flow.
Cc: Ji-Ze Hong (Peter Hong) <peter_hong@fintek.com.tw> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: Vincent Mailhol <mailhol@kernel.org> Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/2026022334-slackness-dynamic-9195@gregkh Fixes: 88da17436973 ("can: usb: f81604: add Fintek F81604 support") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: usb: etas_es58x: correctly anchor the urb in the read bulk callback
When submitting an urb, that is using the anchor pattern, it needs to be
anchored before submitting it otherwise it could be leaked if
usb_kill_anchored_urbs() is called. This logic is correctly done
elsewhere in the driver, except in the read bulk callback so do that
here also.
Cc: Vincent Mailhol <mailhol@kernel.org> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Vincent Mailhol <mailhol@kernel.org> Tested-by: Vincent Mailhol <mailhol@kernel.org> Link: https://patch.msgid.link/2026022320-poser-stiffly-9d84@gregkh Fixes: 8537257874e9 ("can: etas_es58x: add core support for ETAS ES58X CAN USB interfaces") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: ucan: Fix infinite loop from zero-length messages
If a broken ucan device gets a message with the message length field set
to 0, then the driver will loop for forever in
ucan_read_bulk_callback(), hanging the system. If the length is 0, just
skip the message and go on to the next one.
This has been fixed in the kvaser_usb driver in the past in commit 0c73772cd2b8 ("can: kvaser_usb: leaf: Fix potential infinite loop in
command parsers"), so there must be some broken devices out there like
this somewhere.
Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: Vincent Mailhol <mailhol@kernel.org> Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/2026022319-huff-absurd-6a18@gregkh Fixes: 9f2d3eae88d2 ("can: ucan: add driver for Theobroma Systems UCAN devices") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
can: ems_usb: ems_usb_read_bulk_callback(): check the proper length of a message
When looking at the data in a USB urb, the actual_length is the size of
the buffer passed to the driver, not the transfer_buffer_length which is
set by the driver as the max size of the buffer.
When parsing the messages in ems_usb_read_bulk_callback() properly check
the size both at the beginning of parsing the message to make sure it is
big enough for the expected structure, and at the end of the message to
make sure we don't overflow past the end of the buffer for the next
message.
Cc: Vincent Mailhol <mailhol@kernel.org> Cc: Marc Kleine-Budde <mkl@pengutronix.de> Cc: stable@kernel.org Assisted-by: gkh_clanker_2000 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://patch.msgid.link/2026022316-answering-strainer-a5db@gregkh Fixes: 702171adeed3 ("ems_usb: Added support for EMS CPC-USB/ARM7 CAN/USB interface") Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Ziyi Guo [Fri, 13 Feb 2026 20:39:27 +0000 (20:39 +0000)]
can: esd_usb: add endpoint type validation
esd_usb_probe() constructs bulk pipes for two endpoints without
verifying their transfer types:
- usb_rcvbulkpipe(dev->udev, 1) for RX (version reply, async RX data)
- usb_sndbulkpipe(dev->udev, 2) for TX (version query, CAN frames)
A malformed USB device can present these endpoints with transfer types
that differ from what the driver assumes, triggering the WARNING in
usb_submit_urb().
Use usb_find_common_endpoints() to discover and validate the first
bulk IN and bulk OUT endpoints at probe time, before any allocation.
Found pipes are saved to struct esd_usb and code uses them directly
instead of making pipes in place.
Similar to
- commit 136bed0bfd3b ("can: mcba_usb: properly check endpoint type")
which established the usb_find_common_endpoints() + stored pipes
pattern for CAN USB drivers.
Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device") Suggested-by: Vincent Mailhol <mailhol@kernel.org> Signed-off-by: Ziyi Guo <n7l8m4@u.northwestern.edu> Reviewed-by: Vincent Mailhol <mailhol@kernel.org> Link: https://patch.msgid.link/20260213203927.599163-1-n7l8m4@u.northwestern.edu Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Alban Bedel [Mon, 9 Feb 2026 14:47:05 +0000 (15:47 +0100)]
can: mcp251x: fix deadlock in error path of mcp251x_open
The mcp251x_open() function call free_irq() in its error path with the
mpc_lock mutex held. But if an interrupt already occurred the
interrupt handler will be waiting for the mpc_lock and free_irq() will
deadlock waiting for the handler to finish.
This issue is similar to the one fixed in commit 7dd9c26bd6cf ("can:
mcp251x: fix deadlock if an interrupt occurs during mcp251x_open") but
for the error path.
To solve this issue move the call to free_irq() after the lock is
released. Setting `priv->force_quit = 1` beforehand ensure that the IRQ
handler will exit right away once it acquired the lock.
The former implementation was only counting the tx_packets value but not
the tx_bytes as the skb was dropped on driver layer.
Enable CAN echo support (IFF_ECHO) in dummy_can_init(), which activates the
code for setting and retrieving the echo SKB and counts the tx_bytes
correctly.
Fixes: 816cf430e84b ("can: add dummy_can driver") Cc: Vincent Mailhol <mailhol@kernel.org> Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Reviewed-by: Vincent Mailhol <mailhol@kernel.org> Link: https://patch.msgid.link/20260126104540.21024-1-socketcan@hartkopp.net
[mkl: make commit message imperative] Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Oliver Hartkopp [Wed, 18 Feb 2026 10:58:06 +0000 (11:58 +0100)]
can: bcm: fix locking for bcm_op runtime updates
Commit c2aba69d0c36 ("can: bcm: add locking for bcm_op runtime updates")
added a locking for some variables that can be modified at runtime when
updating the sending bcm_op with a new TX_SETUP command in bcm_tx_setup().
Usually the RX_SETUP only handles and filters incoming traffic with one
exception: When the RX_RTR_FRAME flag is set a predefined CAN frame is
sent when a specific RTR frame is received. Therefore the rx bcm_op uses
bcm_can_tx() which uses the bcm_tx_lock that was only initialized in
bcm_tx_setup(). Add the missing spin_lock_init() when allocating the
bcm_op in bcm_rx_setup() to handle the RTR case properly.
Fixes: c2aba69d0c36 ("can: bcm: add locking for bcm_op runtime updates") Reported-by: syzbot+5b11eccc403dd1cea9f8@syzkaller.appspotmail.com Closes: https://lore.kernel.org/linux-can/699466e4.a70a0220.2c38d7.00ff.GAE@google.com/ Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://patch.msgid.link/20260218-bcm_spin_lock_init-v1-1-592634c8a5b5@hartkopp.net Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Raju Rangoju [Thu, 26 Feb 2026 17:07:53 +0000 (22:37 +0530)]
amd-xgbe: fix MAC_TCR_SS register width for 2.5G and 10M speeds
Extend the MAC_TCR_SS (Speed Select) register field width from 2 bits
to 3 bits to properly support all speed settings.
The MAC_TCR register's SS field encoding requires 3 bits to represent
all supported speeds:
- 0x00: 10Gbps (XGMII)
- 0x02: 2.5Gbps (GMII) / 100Mbps
- 0x03: 1Gbps / 10Mbps
- 0x06: 2.5Gbps (XGMII) - P100a only
With only 2 bits, values 0x04-0x07 cannot be represented, which breaks
2.5G XGMII mode on newer platforms and causes incorrect speed select
values to be programmed.
Fixes: 07445f3c7ca1 ("amd-xgbe: Add support for 10 Mbps speed") Co-developed-by: Guruvendra Punugupati <Guruvendra.Punugupati@amd.com> Signed-off-by: Guruvendra Punugupati <Guruvendra.Punugupati@amd.com> Signed-off-by: Raju Rangoju <Raju.Rangoju@amd.com> Link: https://patch.msgid.link/20260226170753.250312-1-Raju.Rangoju@amd.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
net: ti: icssg-prueth: Fix ping failure after offload mode setup when link speed is not 1G
When both eth interfaces with links up are added to a bridge or hsr
interface, ping fails if the link speed is not 1Gbps (e.g., 100Mbps).
The issue is seen because when switching to offload (bridge/hsr) mode,
prueth_emac_restart() restarts the firmware and clears DRAM with
memset_io(), setting all memory to 0. This includes PORT_LINK_SPEED_OFFSET
which firmware reads for link speed. The value 0 corresponds to
FW_LINK_SPEED_1G (0x00), so for 1Gbps links the default value is correct
and ping works. For 100Mbps links, the firmware needs FW_LINK_SPEED_100M
(0x01) but gets 0 instead, causing ping to fail. The function
emac_adjust_link() is called to reconfigure, but it detects no state change
(emac->link is still 1, speed/duplex match PHY) so new_state remains false
and icssg_config_set_speed() is never called to correct the firmware speed
value.
The fix resets emac->link to 0 before calling emac_adjust_link() in
prueth_emac_common_start(). This forces new_state=true, ensuring
icssg_config_set_speed() is called to write the correct speed value to
firmware memory.
Jiayuan Chen [Wed, 25 Feb 2026 12:32:40 +0000 (20:32 +0800)]
atm: lec: fix null-ptr-deref in lec_arp_clear_vccs
syzkaller reported a null-ptr-deref in lec_arp_clear_vccs().
This issue can be easily reproduced using the syzkaller reproducer.
In the ATM LANE (LAN Emulation) module, the same atm_vcc can be shared by
multiple lec_arp_table entries (e.g., via entry->vcc or entry->recv_vcc).
When the underlying VCC is closed, lec_vcc_close() iterates over all
ARP entries and calls lec_arp_clear_vccs() for each matched entry.
For example, when lec_vcc_close() iterates through the hlists in
priv->lec_arp_empty_ones or other ARP tables:
1. In the first iteration, for the first matched ARP entry sharing the VCC,
lec_arp_clear_vccs() frees the associated vpriv (which is vcc->user_back)
and sets vcc->user_back to NULL.
2. In the second iteration, for the next matched ARP entry sharing the same
VCC, lec_arp_clear_vccs() is called again. It obtains a NULL vpriv from
vcc->user_back (via LEC_VCC_PRIV(vcc)) and then attempts to dereference it
via `vcc->pop = vpriv->old_pop`, leading to a null-ptr-deref crash.
Fix this by adding a null check for vpriv before dereferencing
it. If vpriv is already NULL, it means the VCC has been cleared
by a previous call, so we can safely skip the cleanup and just
clear the entry's vcc/recv_vcc pointers.
The entire cleanup block (including vcc_release_async()) is placed inside
the vpriv guard because a NULL vpriv indicates the VCC has already been
fully released by a prior iteration — repeating the teardown would
redundantly set flags and trigger callbacks on an already-closing socket.
The Fixes tag points to the initial commit because the entry->vcc path has
been vulnerable since the original code. The entry->recv_vcc path was later
added by commit 8d9f73c0ad2f ("atm: fix a memory leak of vcc->user_back")
with the same pattern, and both paths are fixed here.
Reported-by: syzbot+72e3ea390c305de0e259@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/68c95a83.050a0220.3c6139.0e5c.GAE@google.com/T/ Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Suggested-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Simon Horman <horms@kernel.org> Signed-off-by: Jiayuan Chen <jiayuan.chen@shopee.com> Link: https://patch.msgid.link/20260225123250.189289-1-jiayuan.chen@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Guenter Roeck [Fri, 27 Feb 2026 05:58:12 +0000 (21:58 -0800)]
dpaa2-switch: Fix interrupt storm after receiving bad if_id in IRQ handler
Commit 31a7a0bbeb00 ("dpaa2-switch: add bounds check for if_id in IRQ
handler") introduces a range check for if_id to avoid an out-of-bounds
access. If an out-of-bounds if_id is detected, the interrupt status is
not cleared. This may result in an interrupt storm.
Clear the interrupt status after detecting an out-of-bounds if_id to avoid
the problem.
Found by an experimental AI code review agent at Google.
Fixes: 31a7a0bbeb00 ("dpaa2-switch: add bounds check for if_id in IRQ handler") Cc: Junrui Luo <moonafterrain@outlook.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com> Link: https://patch.msgid.link/20260227055812.1777915-1-linux@roeck-us.net Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
xsk: Fixes for AF_XDP fragment handling
This series fixes two issues in AF_XDP zero-copy fragment handling:
Patch 1 fixes a buffer leak caused by incorrect list node handling after
commit b692bf9a7543. The list_node field is now reused for both the xskb
pool list and the buffer free list. Using list_del() instead of
list_del_init() causes list_empty() checks in xp_free() to fail, preventing
buffers from being added to the free list.
Patch 2 fixes partial packet delivery to userspace. In the zero-copy path,
if the Rx queue fills up while enqueuing fragments, the remaining fragments
are dropped, causing the application to receive incomplete packets. The fix
ensures the Rx queue has sufficient space for all fragments before starting
to enqueue them.
Nikhil P. Rao [Wed, 25 Feb 2026 00:00:27 +0000 (00:00 +0000)]
xsk: Fix zero-copy AF_XDP fragment drop
AF_XDP should ensure that only a complete packet is sent to application.
In the zero-copy case, if the Rx queue gets full as fragments are being
enqueued, the remaining fragments are dropped.
For the multi-buffer case, add a check to ensure that the Rx queue has
enough space for all fragments of a packet before starting to enqueue
them.
Nikhil P. Rao [Wed, 25 Feb 2026 00:00:26 +0000 (00:00 +0000)]
xsk: Fix fragment node deletion to prevent buffer leak
After commit b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node"),
the list_node field is reused for both the xskb pool list and the buffer
free list, this causes a buffer leak as described below.
xp_free() checks if a buffer is already on the free list using
list_empty(&xskb->list_node). When list_del() is used to remove a node
from the xskb pool list, it doesn't reinitialize the node pointers.
This means list_empty() will return false even after the node has been
removed, causing xp_free() to incorrectly skip adding the buffer to the
free list.
Fix this by using list_del_init() instead of list_del() in all fragment
handling paths, this ensures the list node is reinitialized after removal,
allowing the list_empty() to work correctly.
Fixes: b692bf9a7543 ("xsk: Get rid of xdp_buff_xsk::xskb_list_node") Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Signed-off-by: Nikhil P. Rao <nikhil.rao@amd.com> Link: https://patch.msgid.link/20260225000456.107806-2-nikhil.rao@amd.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
For idpf:
Li Li moves the check for software marker to occur after incrementing
next to clean to avoid re-encountering the same packet. He also adds a
couple of checks to prevent NULL pointer dereferences and NULLs rss_key,
after free, in error path so that later checks are properly evaluated.
Brian Vazquez adjusts IRQ naming to have correlation with netdev naming.
Sreedevi removes validation of action type as part of ntuple rule
deletion.
For ice:
Aaron Ma breaks RDMA initialization into two steps and adjusts calls so
that VSIs are entirely configured before plugging.
Michal Schmidt fixes initialization of loopback VSI to have proper
resources allocated to allow for loopback testing to occur.
For i40e:
Thomas Gleixner fixes a leak of preempt count by replacing get_cpu()
with smp_processor_id().
For ixgbevf:
Jedrzej adds a check for mailbox version before attempting to call an
associated link state call that is supported in that mailbox version.
For e1000e:
Vitaly clears power gating feature for Panther Lake systems to avoid
packet issues.
* '200GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
e1000e: clear DPG_EN after reset to avoid autonomous power-gating
e1000e: introduce new board type for Panther Lake PCH
ixgbevf: fix link setup issue
i40e: Fix preempt count leak in napi poll tracepoint
ice: fix crash in ethtool offline loopback test
ice: recap the VSI and QoS info after rebuild
idpf: Fix flow rule delete failure due to invalid validation
idpf: change IRQ naming to match netdev and ethtool queue numbering
idpf: nullify pointers after they are freed
idpf: skip deallocating txq group's txqs if it is NULL
idpf: skip deallocating bufq_sets from rx_qgrp if it is NULL
idpf: increment completion queue next_to_clean in sw marker wait routine
Jakub Kicinski [Fri, 27 Feb 2026 00:33:59 +0000 (16:33 -0800)]
tcp: give up on stronger sk_rcvbuf checks (for now)
We hit another corner case which leads to TcpExtTCPRcvQDrop
Connections which send RPCs in the 20-80kB range over loopback
experience spurious drops. The exact conditions for most of
the drops I investigated are that:
- socket exchanged >1MB of data so its not completely fresh
- rcvbuf is around 128kB (default, hasn't grown)
- there is ~60kB of data in rcvq
- skb > 64kB arrives
The sum of skb->len (!) of both of the skbs (the one already
in rcvq and the arriving one) is larger than rwnd.
My suspicion is that this happens because __tcp_select_window()
rounds the rwnd up to (1 << wscale) if less than half of
the rwnd has been consumed.
Eric suggests that given the number of Fixes we already have
pointing to 1d2fbaad7cd8 it's probably time to give up on it,
until a bigger revamp of rmem management.
Also while we could risk tweaking the rwnd math, there are other
drops on workloads I investigated, after the commit in question,
not explained by this phenomenon.
udp: Unhash auto-bound connected sk from 4-tuple hash table when disconnected.
Let's say we bind() an UDP socket to the wildcard address with a
non-zero port, connect() it to an address, and disconnect it from
the address.
bind() sets SOCK_BINDPORT_LOCK on sk->sk_userlocks (but not
SOCK_BINDADDR_LOCK), and connect() calls udp_lib_hash4() to put
the socket into the 4-tuple hash table.
It computes a new hash based on the wildcard address and moves
the socket to a new slot in the 4-tuple hash table, leaving a
garbage in the chain that no packet hits.
Let's remove such a socket from 4-tuple hash table when disconnected.
Note that udp_sk(sk)->udp_portaddr_hash needs to be udpated after
udp_hash4_dec(hslot2) in udp_unhash4().
Fixes: 78c91ae2c6de ("ipv4/udp: Add 4-tuple hash for connected socket") Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260227035547.3321327-1-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Long Li [Thu, 26 Feb 2026 19:28:33 +0000 (11:28 -0800)]
net: mana: Ring doorbell at 4 CQ wraparounds
MANA hardware requires at least one doorbell ring every 8 wraparounds
of the CQ. The driver rings the doorbell as a form of flow control to
inform hardware that CQEs have been consumed.
The NAPI poll functions mana_poll_tx_cq() and mana_poll_rx_cq() can
poll up to CQE_POLLING_BUFFER (512) completions per call. If the CQ
has fewer than 512 entries, a single poll call can process more than
4 wraparounds without ringing the doorbell. The doorbell threshold
check also uses ">" instead of ">=", delaying the ring by one extra
CQE beyond 4 wraparounds. Combined, these issues can cause the driver
to exceed the 8-wraparound hardware limit, leading to missed
completions and stalled queues.
Fix this by capping the number of CQEs polled per call to 4 wraparounds
of the CQ in both TX and RX paths. Also change the doorbell threshold
from ">" to ">=" so the doorbell is rung as soon as 4 wraparounds are
reached.
Cc: stable@vger.kernel.org Fixes: 58a63729c957 ("net: mana: Fix doorbell out of order violation and avoid unnecessary doorbell rings") Signed-off-by: Long Li <longli@microsoft.com> Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com> Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://patch.msgid.link/20260226192833.1050807-1-longli@microsoft.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Victor Nogueira [Wed, 25 Feb 2026 13:43:48 +0000 (10:43 -0300)]
net/sched: Only allow act_ct to bind to clsact/ingress qdiscs and shared blocks
As Paolo said earlier [1]:
"Since the blamed commit below, classify can return TC_ACT_CONSUMED while
the current skb being held by the defragmentation engine. As reported by
GangMin Kim, if such packet is that may cause a UaF when the defrag engine
later on tries to tuch again such packet."
act_ct was never meant to be used in the egress path, however some users
are attaching it to egress today [2]. Attempting to reach a middle
ground, we noticed that, while most qdiscs are not handling
TC_ACT_CONSUMED, clsact/ingress qdiscs are. With that in mind, we
address the issue by only allowing act_ct to bind to clsact/ingress
qdiscs and shared blocks. That way it's still possible to attach act_ct to
egress (albeit only with clsact).
Florian Westphal [Thu, 26 Feb 2026 16:19:17 +0000 (17:19 +0100)]
selftests: netfilter: nft_queue.sh: avoid flakes on debug kernels
Jakub reports test flakes on debug kernels:
FAIL: test_udp_gro_ct: Expected software segmentation to occur, had 23 and 17
This test assumes that the kernels nfnetlink_queue module sees N GSO
packets, segments them into M skbs and queues them to userspace for
reinjection.
Hence, if M >= N, no segmentation occurred.
However, its possible that this happens:
- nfnetlink_queue gets GSO packet
- segments that into n skbs
- userspace buffer is full, kernel drops the segmented skbs
-> "toqueue" counter incremented by 1, "fromqueue" is unchanged.
If this happens often enough in a single run, M >= N check triggers
incorrectly.
To solve this, allow the nf_queue.c test program to set the FAIL_OPEN
flag so that the segmented skbs bypass the queueing step in the kernel
if the receive buffer is full.
Also, reduce number of sending socat instances, decrease their priority
and increase nice value for the nf_queue program itself to reduce the
probability of overruns happening in the first place.
Fixes: 59ecffa3995e ("selftests: netfilter: nft_queue.sh: add udp fraglist gro test case") Reported-by: Jakub Kicinski <kuba@kernel.org> Closes: https://lore.kernel.org/netdev/20260218184114.0b405b72@kernel.org/ Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://patch.msgid.link/20260226161920.1205-1-fw@strlen.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Jonas Köppeler [Thu, 26 Feb 2026 11:40:16 +0000 (12:40 +0100)]
net/sched: sch_cake: fixup cake_mq rate adjustment for diffserv config
cake_mq's rate adjustment during the sync periods did not adjust the
rates for every tin in a diffserv config. This lead to inconsistencies
of rates between the tins. Fix this by setting the rates for all tins
during synchronization.
Paul Moses [Mon, 23 Feb 2026 15:05:44 +0000 (15:05 +0000)]
net/sched: act_gate: snapshot parameters with RCU on replace
The gate action can be replaced while the hrtimer callback or dump path is
walking the schedule list.
Convert the parameters to an RCU-protected snapshot and swap updates under
tcf_lock, freeing the previous snapshot via call_rcu(). When REPLACE omits
the entry list, preserve the existing schedule so the effective state is
unchanged.
Fixes: a51c328df310 ("net: qos: introduce a gate control flow action") Cc: stable@vger.kernel.org Signed-off-by: Paul Moses <p@1g4.org> Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> Acked-by: Jamal Hadi Salim <jhs@mojatatu.com> Reviewed-by: Victor Nogueira <victor@mojatatu.com> Link: https://patch.msgid.link/20260223150512.2251594-2-p@1g4.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Chintan Vankar [Tue, 24 Feb 2026 18:13:59 +0000 (23:43 +0530)]
net: ethernet: ti: am65-cpsw-nuss/cpsw-ale: Fix multicast entry handling in ALE table
In the current implementation, flushing multicast entries in MAC mode
incorrectly deletes entries for all ports instead of only the target port,
disrupting multicast traffic on other ports. The cause is adding multicast
entries by setting only host port bit, and not setting the MAC port bits.
Fix this by setting the MAC port's bit in the port mask while adding the
multicast entry. Also fix the flush logic to preserve the host port bit
during removal of MAC port and free ALE entries when mask contains only
host port.
Fixes: 5c50a856d550 ("drivers: net: ethernet: cpsw: add multicast address to ALE table") Signed-off-by: Chintan Vankar <c-vankar@ti.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260224181359.2055322-1-c-vankar@ti.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
====================
bridge: Check relevant options in VLAN range grouping
The br_vlan_opts_eq_range() function determines if consecutive VLANs can
be grouped together in a range for compact netlink notifications. It
currently checks state, tunnel info, and multicast router configuration,
but misses two categories of per-VLAN options that affect the output:
1. User-visible priv_flags (neigh_suppress, mcast_enabled)
2. Port multicast context options (mcast_max_groups, mcast_n_groups)
When VLANs have different settings for these options, they are incorrectly
grouped into ranges, causing netlink notifications to report only one
VLAN's settings for the entire range.
Fix by checking priv_flags equality, but only for flags that affect netlink
output (BR_VLFLAG_NEIGH_SUPPRESS_ENABLED and BR_VLFLAG_MCAST_ENABLED),
and comparing multicast context options (mcast_max_groups, mcast_n_groups).
Add a test with four test cases for each option, to ensure that VLANs with
different values are not grouped into ranges and VLANs with matching
values are properly grouped together.
====================
Danielle Ratson [Wed, 25 Feb 2026 14:39:56 +0000 (16:39 +0200)]
selftests: net: Add bridge VLAN range grouping tests
Add a new test file bridge_vlan_dump.sh with four test cases that verify
VLANs with different per-VLAN options are not incorrectly grouped into
ranges in the dump output.
The tests verify the kernel's br_vlan_opts_eq_range() function correctly
prevents VLAN range grouping when neigh_suppress, mcast_max_groups,
mcast_n_groups, or mcast_enabled options differ.
Each test verifies that VLANs with different option values appear as
individual entries rather than ranges, and that VLANs with matching
values are properly grouped together.
Example output:
$ ./bridge_vlan_dump.sh
TEST: VLAN range grouping with neigh_suppress [ OK ]
TEST: VLAN range grouping with mcast_max_groups [ OK ]
TEST: VLAN range grouping with mcast_n_groups [ OK ]
TEST: VLAN range grouping with mcast_enabled [ OK ]
Danielle Ratson [Wed, 25 Feb 2026 14:39:55 +0000 (16:39 +0200)]
bridge: Check relevant per-VLAN options in VLAN range grouping
The br_vlan_opts_eq_range() function determines if consecutive VLANs can
be grouped together in a range for compact netlink notifications. It
currently checks state, tunnel info, and multicast router configuration,
but misses two categories of per-VLAN options that affect the output:
1. User-visible priv_flags (neigh_suppress, mcast_enabled)
2. Port multicast context (mcast_max_groups, mcast_n_groups)
When VLANs have different settings for these options, they are incorrectly
grouped into ranges, causing netlink notifications to report only one
VLAN's settings for the entire range.
Fix by checking priv_flags equality, but only for flags that affect netlink
output (BR_VLFLAG_NEIGH_SUPPRESS_ENABLED and BR_VLFLAG_MCAST_ENABLED),
and comparing multicast context (mcast_max_groups and mcast_n_groups).
Example showing the bugs before the fix:
$ bridge vlan set vid 10 dev dummy1 neigh_suppress on
$ bridge vlan set vid 11 dev dummy1 neigh_suppress off
$ bridge -d vlan show dev dummy1
port vlan-id
dummy1 10-11
... neigh_suppress on
$ bridge vlan set vid 10 dev dummy1 mcast_max_groups 100
$ bridge vlan set vid 11 dev dummy1 mcast_max_groups 200
$ bridge -d vlan show dev dummy1
port vlan-id
dummy1 10-11
... mcast_max_groups 100
After the fix, VLANs 10 and 11 are shown as separate entries with their
correct individual settings.
Fixes: a1aee20d5db2 ("net: bridge: Add netlink knobs for number / maximum MDB entries") Fixes: 83f6d600796c ("bridge: vlan: Allow setting VLAN neighbor suppression state") Signed-off-by: Danielle Ratson <danieller@nvidia.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Acked-by: Nikolay Aleksandrov <razor@blackwall.org> Link: https://patch.msgid.link/20260225143956.3995415-2-danieller@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Davide Caratti [Tue, 24 Feb 2026 20:28:32 +0000 (21:28 +0100)]
net/sched: ets: fix divide by zero in the offload path
Offloading ETS requires computing each class' WRR weight: this is done by
averaging over the sums of quanta as 'q_sum' and 'q_psum'. Using unsigned
int, the same integer size as the individual DRR quanta, can overflow and
even cause division by zero, like it happened in the following splat:
Linus Torvalds [Thu, 26 Feb 2026 16:00:13 +0000 (08:00 -0800)]
Merge tag 'net-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
"Including fixes from IPsec, Bluetooth and netfilter
Current release - regressions:
- wifi: fix dev_alloc_name() return value check
- rds: fix recursive lock in rds_tcp_conn_slots_available
Current release - new code bugs:
- vsock: lock down child_ns_mode as write-once
Previous releases - regressions:
- core:
- do not pass flow_id to set_rps_cpu()
- consume xmit errors of GSO frames
- netconsole: avoid OOB reads, msg is not nul-terminated
- netfilter: h323: fix OOB read in decode_choice()
- tcp: re-enable acceptance of FIN packets when RWIN is 0
- udplite: fix null-ptr-deref in __udp_enqueue_schedule_skb().
- wifi: brcmfmac: fix potential kernel oops when probe fails
- phy: register phy led_triggers during probe to avoid AB-BA deadlock
- eth:
- bnxt_en: fix deleting of Ntuple filters
- wan: farsync: fix use-after-free bugs caused by unfinished tasklets
- xscale: check for PTP support properly
Previous releases - always broken:
- tcp: fix potential race in tcp_v6_syn_recv_sock()
- kcm: fix zero-frag skb in frag_list on partial sendmsg error
- xfrm:
- fix race condition in espintcp_close()
- always flush state and policy upon NETDEV_UNREGISTER event
- bluetooth:
- purge error queues in socket destructors
- fix response to L2CAP_ECRED_CONN_REQ
- eth:
- mlx5:
- fix circular locking dependency in dump
- fix "scheduling while atomic" in IPsec MAC address query
- gve: fix incorrect buffer cleanup for QPL
- team: avoid NETDEV_CHANGEMTU event when unregistering slave
- usb: validate USB endpoints"
* tag 'net-7.0-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (72 commits)
netfilter: nf_conntrack_h323: fix OOB read in decode_choice()
dpaa2-switch: validate num_ifs to prevent out-of-bounds write
net: consume xmit errors of GSO frames
vsock: document write-once behavior of the child_ns_mode sysctl
vsock: lock down child_ns_mode as write-once
selftests/vsock: change tests to respect write-once child ns mode
net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query
net/mlx5: Fix missing devlink lock in SRIOV enable error path
net/mlx5: E-switch, Clear legacy flag when moving to switchdev
net/mlx5: LAG, disable MPESW in lag_disable_change()
net/mlx5: DR, Fix circular locking dependency in dump
selftests: team: Add a reference count leak test
team: avoid NETDEV_CHANGEMTU event when unregistering slave
net: mana: Fix double destroy_workqueue on service rescan PCI path
MAINTAINERS: Update maintainer entry for QUALCOMM ETHQOS ETHERNET DRIVER
dpll: zl3073x: Remove redundant cleanup in devm_dpll_init()
selftests/net: packetdrill: Verify acceptance of FIN packets when RWIN is 0
tcp: re-enable acceptance of FIN packets when RWIN is 0
vsock: Use container_of() to get net namespace in sysctl handlers
net: usb: kaweth: validate USB endpoints
...
Baochen Qiang [Thu, 29 Jan 2026 02:24:06 +0000 (10:24 +0800)]
wifi: ath12k: fix station lookup failure when disconnecting from AP
In ath12k_wmi_tlv_fw_stats_data_parse() and
ath12k_wmi_tlv_rssi_chain_parse(), the driver uses
ieee80211_find_sta_by_ifaddr() to look up the station associated with the
incoming firmware statistics. This works under normal conditions but fails
during AP disconnection, resulting in log messages like:
wlan0: deauthenticating from xxxxxx by local choice (Reason: 3=DEAUTH_LEAVING)
wlan0: moving STA xxxxxx to state 3
wlan0: moving STA xxxxxx to state 2
wlan0: moving STA xxxxxx to state 1
ath12k_pci 0000:02:00.0: not found station bssid xxxxxx for vdev stat
ath12k_pci 0000:02:00.0: not found station of bssid xxxxxx for rssi chain
ath12k_pci 0000:02:00.0: failed to pull fw stats: -71
ath12k_pci 0000:02:00.0: time out while waiting for get fw stats
wlan0: Removed STA xxxxxx
wlan0: Destroyed STA xxxxxx
The failure happens because the station has already been removed from
ieee80211_local::sta_hash by the time firmware statistics are requested
through drv_sta_statistics().
Switch the lookup to ath12k_link_sta_find_by_addr(), which searches the
driver's link station hash table that still has the station recorded
at that time. This also implicitly fixes another issue: the current code
always uses deflink regardless of which link the statistics belong to,
which is incorrect in MLO scenarios. The new helper returns the correct
link station.
Additionally, raise the log level on lookup failures. With the updated
helper, such failures should no longer occur under normal conditions.
Baochen Qiang [Thu, 29 Jan 2026 02:24:05 +0000 (10:24 +0800)]
wifi: ath12k: use correct pdev id when requesting firmware stats
To get firmware statistics, currently ar->pdev->pdev_id is passed as an
argument to ath12k_mac_get_fw_stats() in ath12k_mac_op_sta_statistics().
For single pdev device like WCN7850, its value is 0 which represents the
SoC pdev id. As a result, WCN7850 firmware sends the same reply to host
twice, which further results in memory leak:
1. ath12k_mac_get_fw_stats() called in ath12k_mac_op_sta_statistics() to
get vdev statistics, making the caller thread wait.
2. firmware sends the first reply, ath12k_wmi_tlv_fw_stats_data_parse()
allocates buffers to cache necessary information. Following that, in
ath12k_wmi_fw_stats_process() if events of all started vdev haved been
received, is_end flag is set hence the waiting thread gets waken up by
the ar->fw_stats_done/->fw_stats_complete signals.
3. ath12k_mac_get_fw_stats() wakes up and returns successfully.
ath12k_mac_op_sta_statistics() saves required parameters and calls
ath12k_fw_stats_reset() to free buffers allocated earlier.
4. firmware sends the second reply. As usual, buffers are allocated and
attached to the ar->fw_stats.vdevs list. Note this time there is no
thread waiting, therefore no chance to free those buffers.
5. ath12k module gets unloaded. If there has been no more firmware
statistics request made since step 4, or if the request fails (see
the example in the following patch), there is no chance to call
ath12k_fw_stats_reset(). Consequently those buffers leak.
Actually for single pdev device, using SoC pdev id in
ath12k_mac_op_sta_statistics() is wrong, because the purpose is to get
statistics of a specific station, which is mapped to a specific pdev. That
said, the id of actual individual pdev should be fetched and used instead.
The helper ath12k_mac_get_target_pdev_id() serves for this purpose, hence
use it to fix this issue. Note it also works for other devices as well due
to the single_pdev_only check inside.
The same applies to ath12k_mac_op_get_txpower() and
ath12k_mac_op_link_sta_statistics() as well.
Fixes: 79e7b04b5388 ("wifi: ath12k: report station mode signal strength") Fixes: e92c658b056b ("wifi: ath12k: add get_txpower mac ops") Fixes: ebebe66ec208 ("wifi: ath12k: fill link station statistics for MLO") Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com> Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com> Link: https://patch.msgid.link/20260129-ath12k-fw-stats-fixes-v1-1-55d66064f4d5@oss.qualcomm.com Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
Vahagn Vardanian [Wed, 25 Feb 2026 13:06:18 +0000 (14:06 +0100)]
netfilter: nf_conntrack_h323: fix OOB read in decode_choice()
In decode_choice(), the boundary check before get_len() uses the
variable `len`, which is still 0 from its initialization at the top of
the function:
unsigned int type, ext, len = 0;
...
if (ext || (son->attr & OPEN)) {
BYTE_ALIGN(bs);
if (nf_h323_error_boundary(bs, len, 0)) /* len is 0 here */
return H323_ERROR_BOUND;
len = get_len(bs); /* OOB read */
When the bitstream is exactly consumed (bs->cur == bs->end), the check
nf_h323_error_boundary(bs, 0, 0) evaluates to (bs->cur + 0 > bs->end),
which is false. The subsequent get_len() call then dereferences
*bs->cur++, reading 1 byte past the end of the buffer. If that byte
has bit 7 set, get_len() reads a second byte as well.
This can be triggered remotely by sending a crafted Q.931 SETUP message
with a User-User Information Element containing exactly 2 bytes of
PER-encoded data ({0x08, 0x00}) to port 1720 through a firewall with
the nf_conntrack_h323 helper active. The decoder fully consumes the
PER buffer before reaching this code path, resulting in a 1-2 byte
heap-buffer-overflow read confirmed by AddressSanitizer.
Fix this by checking for 2 bytes (the maximum that get_len() may read)
instead of the uninitialized `len`. This matches the pattern used at
every other get_len() call site in the same file, where the caller
checks for 2 bytes of available data before calling get_len().
Fixes: ec8a8f3c31dd ("netfilter: nf_ct_h323: Extend nf_h323_error_boundary to work on bits as well") Signed-off-by: Vahagn Vardanian <vahagn@redrays.io> Signed-off-by: Florian Westphal <fw@strlen.de> Link: https://patch.msgid.link/20260225130619.1248-2-fw@strlen.de Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Junrui Luo [Tue, 24 Feb 2026 11:05:56 +0000 (19:05 +0800)]
dpaa2-switch: validate num_ifs to prevent out-of-bounds write
The driver obtains sw_attr.num_ifs from firmware via dpsw_get_attributes()
but never validates it against DPSW_MAX_IF (64). This value controls
iteration in dpaa2_switch_fdb_get_flood_cfg(), which writes port indices
into the fixed-size cfg->if_id[DPSW_MAX_IF] array. When firmware reports
num_ifs >= 64, the loop can write past the array bounds.
Add a bound check for num_ifs in dpaa2_switch_init().
dpaa2_switch_fdb_get_flood_cfg() appends the control interface (port
num_ifs) after all matched ports. When num_ifs == DPSW_MAX_IF and all
ports match the flood filter, the loop fills all 64 slots and the control
interface write overflows by one entry.
The check uses >= because num_ifs == DPSW_MAX_IF is also functionally
broken.
build_if_id_bitmap() silently drops any ID >= 64:
if (id[i] < DPSW_MAX_IF)
bmap[id[i] / 64] |= ...
Jakub Kicinski [Mon, 23 Feb 2026 23:51:00 +0000 (15:51 -0800)]
net: consume xmit errors of GSO frames
udpgro_frglist.sh and udpgro_bench.sh are the flakiest tests
currently in NIPA. They fail in the same exact way, TCP GRO
test stalls occasionally and the test gets killed after 10min.
These tests use veth to simulate GRO. They attach a trivial
("return XDP_PASS;") XDP program to the veth to force TSO off
and NAPI on.
Digging into the failure mode we can see that the connection
is completely stuck after a burst of drops. The sender's snd_nxt
is at sequence number N [1], but the receiver claims to have
received (rcv_nxt) up to N + 3 * MSS [2]. Last piece of the puzzle
is that senders rtx queue is not empty (let's say the block in
the rtx queue is at sequence number N - 4 * MSS [3]).
In this state, sender sends a retransmission from the rtx queue
with a single segment, and sequence numbers N-4*MSS:N-3*MSS [3].
Receiver sees it and responds with an ACK all the way up to
N + 3 * MSS [2]. But sender will reject this ack as TCP_ACK_UNSENT_DATA
because it has no recollection of ever sending data that far out [1].
And we are stuck.
The root cause is the mess of the xmit return codes. veth returns
an error when it can't xmit a frame. We end up with a loss event
like this:
-------------------------------------------------
| GSO super frame 1 | GSO super frame 2 |
|-----------------------------------------------|
| seg | seg | seg | seg | seg | seg | seg | seg |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
-------------------------------------------------
x ok ok <ok>| ok ok ok <x>
\\
snd_nxt
"x" means packet lost by veth, and "ok" means it went thru.
Since veth has TSO disabled in this test it sees individual segments.
Segment 1 is on the retransmit queue and will be resent.
So why did the sender not advance snd_nxt even tho it clearly did
send up to seg 8? tcp_write_xmit() interprets the return code
from the core to mean that data has not been sent at all. Since
TCP deals with GSO super frames, not individual segment the crux
of the problem is that loss of a single segment can be interpreted
as loss of all. TCP only sees the last return code for the last
segment of the GSO frame (in <> brackets in the diagram above).
Of course for the problem to occur we need a setup or a device
without a Qdisc. Otherwise Qdisc layer disconnects the protocol
layer from the device errors completely.
We have multiple ways to fix this.
1) make veth not return an error when it lost a packet.
While this is what I think we did in the past, the issue keeps
reappearing and it's annoying to debug. The game of whack
a mole is not great.
2) fix the damn return codes
We only talk about NETDEV_TX_OK and NETDEV_TX_BUSY in the
documentation, so maybe we should make the return code from
ndo_start_xmit() a boolean. I like that the most, but perhaps
some ancient, not-really-networking protocol would suffer.
3) make TCP ignore the errors
It is not entirely clear to me what benefit TCP gets from
interpreting the result of ip_queue_xmit()? Specifically once
the connection is established and we're pushing data - packet
loss is just packet loss?
4) this fix
Ignore the rc in the Qdisc-less+GSO case, since it's unreliable.
We already always return OK in the TCQ_F_CAN_BYPASS case.
In the Qdisc-less case let's be a bit more conservative and only
mask the GSO errors. This path is taken by non-IP-"networks"
like CAN, MCTP etc, so we could regress some ancient thing.
This is the simplest, but also maybe the hackiest fix?
Similar fix has been proposed by Eric in the past but never committed
because original reporter was working with an OOT driver and wasn't
providing feedback (see Link).
====================
vsock: add write-once semantics to child_ns_mode
Two administrator processes may race when setting child_ns_mode: one
sets it to "local" and creates a namespace, but another changes it to
"global" in between. The first process ends up with a namespace in the
wrong mode. Make child_ns_mode write-once so that a namespace manager
can set it once, check the value, and be guaranteed it won't change
before creating its namespaces. Writing a different value after the
first write returns -EBUSY.
One patch for the implementation, one for docs, and one for tests.
Bobby Eshleman [Mon, 23 Feb 2026 22:38:34 +0000 (14:38 -0800)]
vsock: document write-once behavior of the child_ns_mode sysctl
Update the vsock child_ns_mode documentation to include the new
write-once semantics of setting child_ns_mode. The semantics are
implemented in a preceding patch in this series.
Bobby Eshleman [Mon, 23 Feb 2026 22:38:33 +0000 (14:38 -0800)]
vsock: lock down child_ns_mode as write-once
Two administrator processes may race when setting child_ns_mode as one
process sets child_ns_mode to "local" and then creates a namespace, but
another process changes child_ns_mode to "global" between the write and
the namespace creation. The first process ends up with a namespace in
"global" mode instead of "local". While this can be detected after the
fact by reading ns_mode and retrying, it is fragile and error-prone.
Make child_ns_mode write-once so that a namespace manager can set it
once and be sure it won't change. Writing a different value after the
first write returns -EBUSY. This applies to all namespaces, including
init_net, where an init process can write "local" to lock all future
namespaces into local mode.
Fixes: eafb64f40ca4 ("vsock: add netns to vsock core") Suggested-by: Daan De Meyer <daan.j.demeyer@gmail.com> Suggested-by: Stefano Garzarella <sgarzare@redhat.com> Co-developed-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com> Reviewed-by: Stefano Garzarella <sgarzare@redhat.com> Link: https://patch.msgid.link/20260223-vsock-ns-write-once-v3-2-c0cde6959923@meta.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Bobby Eshleman [Mon, 23 Feb 2026 22:38:32 +0000 (14:38 -0800)]
selftests/vsock: change tests to respect write-once child ns mode
The child_ns_mode sysctl parameter becomes write-once in a future patch
in this series, which breaks existing tests. This patch updates the
tests to respect this new policy. No additional tests are added.
Add "global-parent" and "local-parent" namespaces as intermediaries to
spawn namespaces in the given modes. This avoids the need to change
"child_ns_mode" in the init_ns. nsenter must be used because ip netns
unshares the mount namespace so nested "ip netns add" breaks exec calls
from the init ns. Adds nsenter to the deps check.
Jianbo Liu [Tue, 24 Feb 2026 11:46:52 +0000 (13:46 +0200)]
net/mlx5e: Fix "scheduling while atomic" in IPsec MAC address query
Fix a "scheduling while atomic" bug in mlx5e_ipsec_init_macs() by
replacing mlx5_query_mac_address() with ether_addr_copy() to get the
local MAC address directly from netdev->dev_addr.
The issue occurs because mlx5_query_mac_address() queries the hardware
which involves mlx5_cmd_exec() that can sleep, but it is called from
the mlx5e_ipsec_handle_event workqueue which runs in atomic context.
The MAC address is already available in netdev->dev_addr, so no need
to query hardware. This avoids the sleeping call and resolves the bug.
Shay Drory [Tue, 24 Feb 2026 11:46:51 +0000 (13:46 +0200)]
net/mlx5: Fix missing devlink lock in SRIOV enable error path
The cited commit miss to add locking in the error path of
mlx5_sriov_enable(). When pci_enable_sriov() fails,
mlx5_device_disable_sriov() is called to clean up. This cleanup function
now expects to be called with the devlink instance lock held.
Add the missing devl_lock(devlink) and devl_unlock(devlink)
Fixes: 84a433a40d0e ("net/mlx5: Lock mlx5 devlink reload callbacks") Signed-off-by: Shay Drory <shayd@nvidia.com> Reviewed-by: Mark Bloch <mbloch@nvidia.com> Signed-off-by: Tariq Toukan <tariqt@nvidia.com> Reviewed-by: Simon Horman <horms@kernel.org> Link: https://patch.msgid.link/20260224114652.1787431-5-tariqt@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>