[ Upstream commit e5235eb6cfe02a51256013a78f7b28779a7740d5 ]

Prevent a kernel warning when netconsole setup fails on devices with
IFF_DISABLE_NETPOLL flag. The warning (at kernel/workqueue.c:4242 in
__flush_work) occurs because the cleanup path tries to cancel an
uninitialized work queue.

When __netpoll_setup() encounters a device with IFF_DISABLE_NETPOLL,
it fails early and calls skb_pool_flush() for cleanup. This function
calls cancel_work_sync(&np->refill_wq), but refill_wq hasn't been
initialized yet, triggering the warning.

Move INIT_WORK() to the beginning of __netpoll_setup(), ensuring the
work queue is properly initialized before any potential failure points.
This allows the cleanup path to safely cancel the work queue regardless
of where the setup fails.

Fixes: 248f6571fd4c5 ("netpoll: Optimize skb refilling on critical path")
Signed-off-by: Breno Leitao <leitao@debian.org>
Link: https://patch.msgid.link/20251127-netpoll_fix_init_work-v1-1-65c07806d736@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit d946f3c98328171fa50ddb908593cf833587f725 ]

The bpf_skb_check_mtu helper needs to use skb->transport_header when
the BPF_MTU_CHK_SEGS flag is used:

	bpf_skb_check_mtu(skb, ifindex, &mtu_len, 0, BPF_MTU_CHK_SEGS)

The transport_header is not always set. There is a WARN_ON_ONCE
report when CONFIG_DEBUG_NET is enabled + skb->gso_size is set +
bpf_prog_test_run is used:

WARNING: CPU: 1 PID: 2216 at ./include/linux/skbuff.h:3071
 skb_gso_validate_network_len
 bpf_skb_check_mtu
 bpf_prog_3920e25740a41171_tc_chk_segs_flag # A test in the next patch
 bpf_test_run
 bpf_prog_test_run_skb

For a normal ingress skb (not test_run), skb_reset_transport_header
is performed but there is plan to avoid setting it as described in
commit 2170a1f09148 ("net: no longer reset transport_header in __netif_receive_skb_core()").

This patch fixes the bpf helper by checking
skb_transport_header_was_set(). The check is done just before
skb->transport_header is used, to avoid breaking the existing bpf prog.
The WARN_ON_ONCE is limited to bpf_prog_test_run, so targeting bpf-next.

Fixes: 34b2021cc616 ("bpf: Add BPF-helper for MTU checking")
Cc: Jesper Dangaard Brouer <hawk@kernel.org>
Reported-by: Kaiyan Mei <M202472210@hust.edu.cn>
Reported-by: Yinhao Hu <dddddd@hust.edu.cn>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20251112232331.1566074-1-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit c07a491c1b735e0c27454ea5c27a446d43401b1e ]

Need to call netdev_get_by_index_lock() from io_uring/zcrx.c, but it is
currently private to net. Export the function in linux/netdevice.h.

Signed-off-by: David Wei <dw@davidwei.uk>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Stable-dep-of: b6c5f9454ef3 ("io_uring/zcrx: call netdev_queue_get_dma_dev() under instance lock")
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 04a899573fb87273a656f178b5f920c505f68875 ]

Yinhao et al. reported that their fuzzer tool was able to trigger a
skb_warn_bad_offload() from netif_skb_features() -> gso_features_check().
When a BPF program - triggered via BPF test infra - pushes the packet
to the loopback device via bpf_clone_redirect() then mentioned offload
warning can be seen. GSO-related features are then rightfully disabled.

We get into this situation due to convert___skb_to_skb() setting
gso_segs and gso_size but not gso_type. Technically, it makes sense
that this warning triggers since the GSO properties are malformed due
to the gso_type. Potentially, the gso_type could be marked non-trustworthy
through setting it at least to SKB_GSO_DODGY without any other specific
assumptions, but that also feels wrong given we should not go further
into the GSO engine in the first place.

The checks were added in 121d57af308d ("gso: validate gso_type in GSO
handlers") because there were malicious (syzbot) senders that combine
a protocol with a non-matching gso_type. If we would want to drop such
packets, gso_features_check() currently only returns feature flags via
netif_skb_features(), so one location for potentially dropping such skbs
could be validate_xmit_unreadable_skb(), but then otoh it would be
an additional check in the fast-path for a very corner case. Given
bpf_clone_redirect() is the only place where BPF test infra could emit
such packets, lets reject them right there.

Fixes: 850a88cc4096 ("bpf: Expose __sk_buff wire_len/gso_segs to BPF_PROG_TEST_RUN")
Fixes: cf62089b0edd ("bpf: Add gso_size to __sk_buff")
Reported-by: Yinhao Hu <dddddd@hust.edu.cn>
Reported-by: Kaiyan Mei <M202472210@hust.edu.cn>
Reported-by: Dongliang Mu <dzm91@hust.edu.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20251020075441.127980-1-daniel@iogearbox.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

The ethtool tsconfig Netlink path can trigger a null pointer
dereference. A call chain such as:

  tsconfig_prepare_data() ->
  dev_get_hwtstamp_phylib() ->
  vlan_hwtstamp_get() ->
  generic_hwtstamp_get_lower() ->
  generic_hwtstamp_ioctl_lower()

results in generic_hwtstamp_ioctl_lower() being called with
kernel_cfg->ifr as NULL.

The generic_hwtstamp_ioctl_lower() function does not expect
a NULL ifr and dereferences it, leading to a system crash.

Fix this by adding a NULL check for kernel_cfg->ifr in
generic_hwtstamp_ioctl_lower(). If ifr is NULL, return -EINVAL.

Fixes: 6e9e2eed4f39 ("net: ethtool: Add support for tsconfig command to get/set hwtstamp config")
Closes: https://lore.kernel.org/cd6a7056-fa6d-43f8-b78a-f5e811247ba8@linux.dev
Signed-off-by: Jiaming Zhang <r772577952@gmail.com>
Reviewed-by: Kory Maincent <kory.maincent@bootlin.com>
Link: https://patch.msgid.link/20251111173652.749159-2-r772577952@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

commit efa95b01da18 ("netpoll: fix use after free") incorrectly
ignored the refcount and prematurely set dev->npinfo to NULL during
netpoll cleanup, leading to improper behavior and memory leaks.

Scenario causing lack of proper cleanup:

1) A netpoll is associated with a NIC (e.g., eth0) and netdev->npinfo is
   allocated, and refcnt = 1
   - Keep in mind that npinfo is shared among all netpoll instances. In
     this case, there is just one.

2) Another netpoll is also associated with the same NIC and
   npinfo->refcnt += 1.
   - Now dev->npinfo->refcnt = 2;
   - There is just one npinfo associated to the netdev.

3) When the first netpolls goes to clean up:
   - The first cleanup succeeds and clears np->dev->npinfo, ignoring
     refcnt.
     - It basically calls `RCU_INIT_POINTER(np->dev->npinfo, NULL);`
   - Set dev->npinfo = NULL, without proper cleanup
   - No ->ndo_netpoll_cleanup() is either called

4) Now the second target tries to clean up
   - The second cleanup fails because np->dev->npinfo is already NULL.
     * In this case, ops->ndo_netpoll_cleanup() was never called, and
       the skb pool is not cleaned as well (for the second netpoll
       instance)
  - This leaks npinfo and skbpool skbs, which is clearly reported by
    kmemleak.

Revert commit efa95b01da18 ("netpoll: fix use after free") and adds
clarifying comments emphasizing that npinfo cleanup should only happen
once the refcount reaches zero, ensuring stable and correct netpoll
behavior.

Cc: <stable@vger.kernel.org> # 3.17.x
Cc: Jay Vosburgh <jv@jvosburgh.net>
Fixes: efa95b01da18 ("netpoll: fix use after free")
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251107-netconsole_torture-v10-1-749227b55f63@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull networking fixes from Jakub Kicinski:
  Including fixes from bluetooth and wireless.

  Current release - new code bugs:

   - ptp: expose raw cycles only for clocks with free-running counter

   - bonding: fix null-deref in actor_port_prio setting

   - mdio: ERR_PTR-check regmap pointer returned by
     device_node_to_regmap()

   - eth: libie: depend on DEBUG_FS when building LIBIE_FWLOG

  Previous releases - regressions:

   - virtio_net: fix perf regression due to bad alignment of
     virtio_net_hdr_v1_hash

   - Revert "wifi: ath10k: avoid unnecessary wait for service ready
     message" caused regressions for QCA988x and QCA9984

   - Revert "wifi: ath12k: Fix missing station power save configuration"
     caused regressions for WCN7850

   - eth: bnxt_en: shutdown FW DMA in bnxt_shutdown(), fix memory
     corruptions after kexec

  Previous releases - always broken:

   - virtio-net: fix received packet length check for big packets

   - sctp: fix races in socket diag handling

   - wifi: add an hrtimer-based delayed work item to avoid low
     granularity of timers set relatively far in the future, and use it
     where it matters (e.g. when performing AP-scheduled channel switch)

   - eth: mlx5e:
       - correctly propagate error in case of module EEPROM read failure
       - fix HW-GRO on systems with PAGE_SIZE == 64kB

   - dsa: b53: fixes for tagging, link configuration / RMII, FDB,
     multicast

   - phy: lan8842: implement latest errata"

* tag 'net-6.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (63 commits)
  selftests/vsock: avoid false-positives when checking dmesg
  net: bridge: fix MST static key usage
  net: bridge: fix use-after-free due to MST port state bypass
  lan966x: Fix sleeping in atomic context
  bonding: fix NULL pointer dereference in actor_port_prio setting
  net: dsa: microchip: Fix reserved multicast address table programming
  net: wan: framer: pef2256: Switch to devm_mfd_add_devices()
  net: libwx: fix device bus LAN ID
  net/mlx5e: SHAMPO, Fix header formulas for higher MTUs and 64K pages
  net/mlx5e: SHAMPO, Fix skb size check for 64K pages
  net/mlx5e: SHAMPO, Fix header mapping for 64K pages
  net: ti: icssg-prueth: Fix fdb hash size configuration
  net/mlx5e: Fix return value in case of module EEPROM read error
  net: gro_cells: Reduce lock scope in gro_cell_poll
  libie: depend on DEBUG_FS when building LIBIE_FWLOG
  wifi: mac80211_hwsim: Limit destroy_on_close radio removal to netgroup
  netpoll: Fix deadlock in memory allocation under spinlock
  net: ethernet: ti: netcp: Standardize knav_dma_open_channel to return NULL on error
  virtio-net: fix received length check in big packets
  bnxt_en: Fix warning in bnxt_dl_reload_down()
  ...

One GRO-cell device's NAPI callback can nest into the GRO-cell of
another device if the underlying device is also using GRO-cell.
This is the case for IPsec over vxlan.
These two GRO-cells are separate devices. From lockdep's point of view
it is the same because each device is sharing the same lock class and so
it reports a possible deadlock assuming one device is nesting into
itself.

Hold the bh_lock only while accessing gro_cell::napi_skbs in
gro_cell_poll(). This reduces the locking scope and avoids acquiring the
same lock class multiple times.

Fixes: 25718fdcbdd2 ("net: gro_cells: Use nested-BH locking for gro_cell")
Reported-by: Gal Pressman <gal@nvidia.com>
Closes: https://lore.kernel.org/all/66664116-edb8-48dc-ad72-d5223696dd19@nvidia.com/
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://patch.msgid.link/20251104153435.ty88xDQt@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Fix a AA deadlock in refill_skbs() where memory allocation while holding
skb_pool->lock can trigger a recursive lock acquisition attempt.

The deadlock scenario occurs when the system is under severe memory
pressure:

1. refill_skbs() acquires skb_pool->lock (spinlock)
2. alloc_skb() is called while holding the lock
3. Memory allocator fails and calls slab_out_of_memory()
4. This triggers printk() for the OOM warning
5. The console output path calls netpoll_send_udp()
6. netpoll_send_udp() attempts to acquire the same skb_pool->lock
7. Deadlock: the lock is already held by the same CPU

Call stack:
  refill_skbs()
    spin_lock_irqsave(&skb_pool->lock)    <- lock acquired
    __alloc_skb()
      kmem_cache_alloc_node_noprof()
        slab_out_of_memory()
          printk()
            console_flush_all()
              netpoll_send_udp()
                skb_dequeue()
                  spin_lock_irqsave(&skb_pool->lock)     <- deadlock attempt

This bug was exposed by commit 248f6571fd4c51 ("netpoll: Optimize skb
refilling on critical path") which removed refill_skbs() from the
critical path (where nested printk was being deferred), letting nested
printk being called from inside refill_skbs()

Refactor refill_skbs() to never allocate memory while holding
the spinlock.

Another possible solution to fix this problem is protecting the
refill_skbs() from nested printks, basically calling
printk_deferred_{enter,exit}() in refill_skbs(), then, any nested
pr_warn() would be deferred.

I prefer this approach, given I _think_ it might be a good idea to move
the alloc_skb() from GFP_ATOMIC to GFP_KERNEL in the future, so, having
the alloc_skb() outside of the lock will be necessary step.

There is a possible TOCTOU issue when checking for the pool length, and
queueing the new allocated skb, but, this is not an issue, given that
an extra SKB in the pool is harmless and it will be eventually used.

Signed-off-by: Breno Leitao <leitao@debian.org>
Fixes: 248f6571fd4c51 ("netpoll: Optimize skb refilling on critical path")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20251103-fix_netpoll_aa-v4-1-4cfecdf6da7c@debian.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Pull bpf fixes from Alexei Starovoitov:

 - Mark migrate_disable/enable() as always_inline to avoid issues with
   partial inlining (Yonghong Song)

 - Fix powerpc stack register definition in libbpf bpf_tracing.h (Andrii
   Nakryiko)

 - Reject negative head_room in __bpf_skb_change_head (Daniel Borkmann)

 - Conditionally include dynptr copy kfuncs (Malin Jonsson)

 - Sync pending IRQ work before freeing BPF ring buffer (Noorain Eqbal)

 - Do not audit capability check in x86 do_jit() (Ondrej Mosnacek)

 - Fix arm64 JIT of BPF_ST insn when it writes into arena memory
   (Puranjay Mohan)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  bpf/arm64: Fix BPF_ST into arena memory
  bpf: Make migrate_disable always inline to avoid partial inlining
  bpf: Reject negative head_room in __bpf_skb_change_head
  bpf: Conditionally include dynptr copy kfuncs
  libbpf: Fix powerpc's stack register definition in bpf_tracing.h
  bpf: Do not audit capability check in do_jit()
  bpf: Sync pending IRQ work before freeing ring buffer