linux-stable.git/include/net, branch v6.12.97

Bluetooth: L2CAP: Fix regressions caused by reusing ident

2026-07-24T14:11:56+00:00

commit 761fb8ec8778f0caf2bba5a41e3cff1ea86974f3 upstream.

This attempt to fix regressions caused by reusing ident which apparently
is not handled well on certain stacks causing the stack to not respond to
requests, so instead of simple returning the first unallocated id this
stores the last used tx_ident and then attempt to use the next until all
available ids are exausted and then cycle starting over to 1.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=221120
Link: https://bugzilla.kernel.org/show_bug.cgi?id=221177
Fixes: 6c3ea155e5ee ("Bluetooth: L2CAP: Fix not tracking outstanding TX ident")
Signed-off-by: Luiz Augusto von Dentz 
Tested-by: Christian Eggers 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_core: Remove check of BDADDR_ANY in hci_conn_hash_lookup_big_state

2026-07-24T14:11:56+00:00

commit 59710a26a289ad4e7ef227d22063e964930928b0 upstream.

The check for destination to be BDADDR_ANY is no longer necessary with
the introduction of BIS_LINK.

Fixes: 23205562ffc8 ("Bluetooth: separate CIS_LINK and BIS_LINK link types")
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Greg Kroah-Hartman

udp_tunnel: fix deadlock in udp_tunnel_nic_set_port_priv()

2026-07-24T14:11:56+00:00

commit c9e78afa688afec528784b79bb02d513cdcd6527 upstream.

While configuring a vxlan tunnel in a system with a i40e NIC driver, I
observe the following deadlock:

 WARNING: possible recursive locking detected
 6.16.0-rc2.net-next-6.16_92d87230d899+ #13 Tainted: G            E
 --------------------------------------------
 kworker/u256:4/1125 is trying to acquire lock:
 ffff88921ab9c8c8 (&utn->lock){+.+.}-{4:4}, at: i40e_udp_tunnel_set_port (/home/pabeni/net-next/include/net/udp_tunnel.h:343 /home/pabeni/net-next/drivers/net/ethernet/intel/i40e/i40e_main.c:13013) i40e

 but task is already holding lock:
 ffff88921ab9c8c8 (&utn->lock){+.+.}-{4:4}, at: udp_tunnel_nic_device_sync_work (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:739) udp_tunnel

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&utn->lock);
   lock(&utn->lock);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by kworker/u256:4/1125:
 #0: ffff8892910ca158 ((wq_completion)udp_tunnel_nic){+.+.}-{0:0}, at: process_one_work (/home/pabeni/net-next/kernel/workqueue.c:3213)
 #1: ffffc900244efd30 ((work_completion)(&utn->work)){+.+.}-{0:0}, at: process_one_work (/home/pabeni/net-next/kernel/workqueue.c:3214)
 #2: ffffffff9a14e290 (rtnl_mutex){+.+.}-{4:4}, at: udp_tunnel_nic_device_sync_work (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:737) udp_tunnel
 #3: ffff88921ab9c8c8 (&utn->lock){+.+.}-{4:4}, at: udp_tunnel_nic_device_sync_work (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:739) udp_tunnel

 stack backtrace:
 Hardware name: Dell Inc. PowerEdge R7525/0YHMCJ, BIOS 2.2.5 04/08/2021
i
 Call Trace:
  
 dump_stack_lvl (/home/pabeni/net-next/lib/dump_stack.c:123)
 print_deadlock_bug (/home/pabeni/net-next/kernel/locking/lockdep.c:3047)
 validate_chain (/home/pabeni/net-next/kernel/locking/lockdep.c:3901)
 __lock_acquire (/home/pabeni/net-next/kernel/locking/lockdep.c:5240)
 lock_acquire.part.0 (/home/pabeni/net-next/kernel/locking/lockdep.c:473 /home/pabeni/net-next/kernel/locking/lockdep.c:5873)
 __mutex_lock (/home/pabeni/net-next/kernel/locking/mutex.c:604 /home/pabeni/net-next/kernel/locking/mutex.c:747)
 i40e_udp_tunnel_set_port (/home/pabeni/net-next/include/net/udp_tunnel.h:343 /home/pabeni/net-next/drivers/net/ethernet/intel/i40e/i40e_main.c:13013) i40e
 udp_tunnel_nic_device_sync_by_port (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:230 /home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:249) udp_tunnel
 __udp_tunnel_nic_device_sync.part.0 (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:292) udp_tunnel
 udp_tunnel_nic_device_sync_work (/home/pabeni/net-next/net/ipv4/udp_tunnel_nic.c:742) udp_tunnel
 process_one_work (/home/pabeni/net-next/kernel/workqueue.c:3243)
 worker_thread (/home/pabeni/net-next/kernel/workqueue.c:3315 /home/pabeni/net-next/kernel/workqueue.c:3402)
 kthread (/home/pabeni/net-next/kernel/kthread.c:464)

AFAICS all the existing callsites of udp_tunnel_nic_set_port_priv() are
already under the utn lock scope, avoid (re-)acquiring it in such a
function.

Fixes: 1ead7501094c ("udp_tunnel: remove rtnl_lock dependency")
Signed-off-by: Paolo Abeni 
Acked-by: Stanislav Fomichev 
Link: https://patch.msgid.link/95a827621ec78c12d1564ec3209e549774f9657d.1750675978.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: L2CAP: Fix use-after-free in l2cap_sock_new_connection_cb()

2026-07-24T14:11:50+00:00

[ Upstream commit 6fef032af0092ed5ccb767239a9ac1bc38c08a40 ]

l2cap_sock_new_connection_cb() returned l2cap_pi(sk)->chan after
release_sock(parent). Once the parent lock is dropped the newly
enqueued child socket sk is reachable via the accept queue, so another
task can accept and free it before the callback dereferences sk,
resulting in a use-after-free.

Rework the ->new_connection() op so the core, rather than the callback,
owns the child channel's lifetime. The op now receives a pre-allocated
new_chan and returns an errno instead of allocating and returning a
channel. l2cap_new_connection() allocates the child channel and links
it into the conn list via __l2cap_chan_add() before invoking the
callback, so the conn-list reference keeps the channel alive once
release_sock(parent) exposes the socket to other tasks.

Channel configuration that was duplicated in l2cap_sock_init() and the
various new_connection callbacks is consolidated into
l2cap_chan_set_defaults(), which now inherits from the parent channel
when one is supplied.

Fixes: 8ffb929098a5 ("Bluetooth: Remove parent socket usage from l2cap_core.c")
Cc: stable@kernel.org
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Siwei Zhang 
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()

2026-07-24T14:11:50+00:00

[ Upstream commit 12917f591cea1af36087dba5b9ec888652f0b42a ]

hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection
was pending, but hdev->sent_cmd can be NULL while req_status is still
HCI_REQ_PEND, leading to a NULL pointer dereference and a general
protection fault from the hci_rx_work() receive path.

Instead of inspecting hdev->sent_cmd, track the in-flight create
connection command with a new per-connection HCI_CONN_CREATE flag and
route all cancellation through hci_cancel_connect_sync(), which
dispatches to a dedicated per-type cancel function. The create command
is in exactly one of two states: still queued, or in flight. The cancel
function holds cmd_sync_work_lock across the whole decision: the worker
takes this lock to dequeue every entry, so while it is held a queued
command cannot start running and an in-flight command cannot complete
and let the next command become pending. This keeps the flag test and
hci_cmd_sync_cancel() atomic with respect to the worker, so a queued
command is simply dequeued, and an in-flight command owned by this
connection is cancelled without the risk of cancelling an unrelated
command that became pending in the meantime. CIS uses the same flag
mechanism via HCI_CONN_CREATE_CIS but cannot be dequeued per-connection.

hci_acl_create_conn_sync() and hci_le_create_conn_sync() clear
HCI_CONN_CREATE after the create command completes, but the command
status handler can free conn via hci_conn_del() (for example when the
controller rejects the connection) while the worker is still blocked on
the connection complete event. Hold a reference on conn across the
create command so the flag can be cleared without a use-after-free.

Fixes: a13f316e90fd ("Bluetooth: hci_conn: Consolidate code for aborting connections")
Cc: stable@vger.kernel.org
Suggested-by: XIAO WU 
Assisted-by: Claude:claude-opus-4-8
Signed-off-by: Siwei Zhang 
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: separate CIS_LINK and BIS_LINK link types

2026-07-24T14:11:50+00:00

[ Upstream commit 23205562ffc8de20f57afdd984858cab29e77968 ]

Use separate link type id for unicast and broadcast ISO connections.
These connection types are handled with separate HCI commands, socket
API is different, and hci_conn has union fields that are different in
the two cases, so they shall not be mixed up.

Currently in most places it is attempted to distinguish ucast by
bacmp(&c->dst, BDADDR_ANY) but it is wrong as dst is set for bcast sink
hci_conn in iso_conn_ready(). Additionally checking sync_handle might be
OK, but depends on details of bcast conn configuration flow.

To avoid complicating it, use separate link types.

Fixes: f764a6c2c1e4 ("Bluetooth: ISO: Add broadcast support")
Signed-off-by: Pauli Virtanen 
Signed-off-by: Luiz Augusto von Dentz 
Stable-dep-of: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_core: Enable buffer flow control for SCO/eSCO

2026-07-24T14:11:50+00:00

[ Upstream commit 13218453521d75916dfed55efb8e809bfc03cb4b ]

This enables buffer flow control for SCO/eSCO
(see: Bluetooth Core 6.0 spec: 6.22. Synchronous Flow Control Enable),
recently this has caused the following problem and is actually a nice
addition for the likes of Socket TX complete:

< HCI Command: Read Buffer Size (0x04|0x0005) plen 0
> HCI Event: Command Complete (0x0e) plen 11
      Read Buffer Size (0x04|0x0005) ncmd 1
        Status: Success (0x00)
        ACL MTU: 1021 ACL max packet: 5
        SCO MTU: 240  SCO max packet: 8
...
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
< SCO Data TX: Handle 257 flags 0x00 dlen 120
> HCI Event: Hardware Error (0x10) plen 1
        Code: 0x0a

To fix the code will now attempt to enable buffer flow control when
HCI_QUIRK_SYNC_FLOWCTL_SUPPORTED is set by the driver:

< HCI Command: Write Sync Fl.. (0x03|0x002f) plen 1
        Flow control: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4
      Write Sync Flow Control Enable (0x03|0x002f) ncmd 1
        Status: Success (0x00)

On success then HCI_SCO_FLOWCTL would be set which indicates sco_cnt
shall be used for flow contro.

Fixes: 7fedd3bb6b77 ("Bluetooth: Prioritize SCO traffic")
Signed-off-by: Luiz Augusto von Dentz 
Tested-by: Pauli Virtanen 
Stable-dep-of: 12917f591cea ("Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: L2CAP: Fix not tracking outstanding TX ident

2026-07-24T14:11:49+00:00

[ Upstream commit 6c3ea155e5ee3e56606233acde8309afda66d483 ]

This attempts to proper track outstanding request by using struct ida
and allocating from it in l2cap_get_ident using ida_alloc_range which
would reuse ids as they are free, then upon completion release
the id using ida_free.

This fixes the qualification test case L2CAP/COS/CED/BI-29-C which
attempts to check if the host stack is able to work after 256 attempts
to connect which requires Ident field to use the full range of possible
values in order to pass the test.

Link: https://github.com/bluez/bluez/issues/1829
Signed-off-by: Luiz Augusto von Dentz 
Reviewed-by: Paul Menzel 
Stable-dep-of: 2641a9e0a1dd ("Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock")
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref

2026-07-24T14:11:49+00:00

[ Upstream commit b66774b48dd98f07254951f74ea6f513efe7ff8b ]

l2cap_chan_timeout() runs asynchronously and accesses chan->conn. If
the connection is torn down while the timer is running or pending,
chan->conn can be freed, leading to a use-after-free when the timer
worker attempts to lock conn->lock:

| BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
| BUG: KASAN: slab-use-after-free in atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:4456 [inline]
| BUG: KASAN: slab-use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:161 [inline]
| BUG: KASAN: slab-use-after-free in mutex_lock+0x4f/0xa0 kernel/locking/mutex.c:318
| Write of size 8 at addr ffff8881298d9550 by task kworker/2:1/83
|
| CPU: 2 UID: 0 PID: 83 Comm: kworker/2:1 Not tainted 7.1.0-rc6-next-20260601-dirty #6 PREEMPT(full)
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
| Workqueue: events l2cap_chan_timeout
| Call Trace:
|  
|  instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
|  atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:4456 [inline]
|  __mutex_trylock_fast kernel/locking/mutex.c:161 [inline]
|  mutex_lock+0x4f/0xa0 kernel/locking/mutex.c:318
|  l2cap_chan_timeout+0x5d/0x1b0 net/bluetooth/l2cap_core.c:422
|  process_one_work kernel/workqueue.c:3326 [inline]
|  process_scheduled_works+0x7c8/0xfb0 kernel/workqueue.c:3409
|  worker_thread+0x8a9/0xcf0 kernel/workqueue.c:3490
|  kthread+0x346/0x430 kernel/kthread.c:436
|  ret_from_fork+0x1a3/0x470 arch/x86/kernel/process.c:158
|  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
|  
|
| Allocated by task 320:
|  l2cap_conn_add+0xa7/0x820 net/bluetooth/l2cap_core.c:7075
|  l2cap_connect_cfm+0xdb/0xd70 net/bluetooth/l2cap_core.c:7452
|  hci_connect_cfm include/net/bluetooth/hci_core.h:2139 [inline]
|  hci_remote_features_evt+0x52f/0x9f0 net/bluetooth/hci_event.c:3760
|  hci_event_func net/bluetooth/hci_event.c:7796 [inline]
|  hci_event_packet+0x561/0xa70 net/bluetooth/hci_event.c:7847
|  hci_rx_work+0x370/0x890 net/bluetooth/hci_core.c:4040
|  process_one_work kernel/workqueue.c:3326 [inline]
|  process_scheduled_works+0x7c8/0xfb0 kernel/workqueue.c:3409
|  worker_thread+0x8a9/0xcf0 kernel/workqueue.c:3490
|  kthread+0x346/0x430 kernel/kthread.c:436
|  ret_from_fork+0x1a3/0x470 arch/x86/kernel/process.c:158
|  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
|
| Freed by task 322:
|  hci_disconn_cfm include/net/bluetooth/hci_core.h:2154 [inline]
|  hci_conn_hash_flush+0x101/0x1f0 net/bluetooth/hci_conn.c:2736
|  hci_dev_close_sync+0x889/0xde0 net/bluetooth/hci_sync.c:5405
|  hci_dev_do_close net/bluetooth/hci_core.c:502 [inline]
|  hci_unregister_dev+0x1f7/0x370 net/bluetooth/hci_core.c:2679
|  vhci_release+0x12a/0x180 drivers/bluetooth/hci_vhci.c:690
|  __fput+0x369/0x890 fs/file_table.c:510
|  task_work_run+0x160/0x1d0 kernel/task_work.c:233
|  get_signal+0xf5b/0x1120 kernel/signal.c:2810
|  arch_do_signal_or_restart+0x4d/0x600 arch/x86/kernel/signal.c:337
|  __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
|  exit_to_user_mode_loop+0x85/0x510 kernel/entry/common.c:98
|  do_syscall_64+0x263/0x3d0 arch/x86/entry/syscall_64.c:100
|  entry_SYSCALL_64_after_hwframe+0x77/0x7f
|
| The buggy address belongs to the object at ffff8881298d9400
|  which belongs to the cache kmalloc-512 of size 512
| The buggy address is located 336 bytes inside of
|  freed 512-byte region [ffff8881298d9400, ffff8881298d9600)

Fix it by having chan->conn hold a reference to l2cap_conn (via
l2cap_conn_get) when the channel is added to the connection, and
releasing it in the channel destructor. This ensures the l2cap_conn
remains alive as long as the channel exists.

A new FLAG_DEL channel flag is introduced to indicate that the channel
has been deleted from its connection. l2cap_chan_del() atomically sets
this flag using test_and_set_bit() instead of setting chan->conn to
NULL. All asynchronous workers (l2cap_chan_timeout, l2cap_ack_timeout,
l2cap_monitor_timeout, l2cap_retrans_timeout) and l2cap_chan_send()
check FLAG_DEL to determine whether the channel has been torn down,
rather than testing chan->conn for NULL.

Fixes: 8c8e620467a7 ("Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen()")
Cc: 
Cc: Siwei Zhang 
Cc: Luiz Augusto von Dentz 
Assisted-by: Gemini:gemini-3.1-pro-preview
Reported-by: https://sashiko.dev/#/patchset/20260521021249.3258069-1-oss%40fourdim.xyz
Signed-off-by: Marco Elver 
Signed-off-by: Luiz Augusto von Dentz 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_queue: pin bridge device while NFQUEUE holds fake dst

2026-07-24T14:11:28+00:00

commit c9c9b37f8c5505224e8d206184df3bb668ee00cf upstream.

The br_netfilter fake rtable is embedded in struct net_bridge and is
attached to bridged packets with skb_dst_set_noref(). If such a packet is
queued to NFQUEUE, __nf_queue() upgrades that fake dst with
skb_dst_force().

At that point the queued skb can hold a real dst reference after bridge
teardown has started. The problem is not that every bridged packet needs
its own dst reference. The problem is that NFQUEUE can keep the bridge
private fake dst alive after unregister begins.

Fix this by keeping the bridge fake dst model unchanged and pinning the
bridge master device only while the packet sits in NFQUEUE. Record the
bridge device in nf_queue_entry when the queued skb carries a bridge fake
dst, take a device reference for the queue lifetime, and drop it when the
queue entry is freed.

Also make sure queued entries are reaped when that bridge device goes
down, and drop the redundant nf_bridge_info_exists() test from the fake
dst detection.

This keeps netdev_priv(br->dev) alive until verdict completion, so the
embedded fake rtable and its metrics backing storage cannot be freed out
from under dst_release(). It also avoids the constant refcount bump and
avoids using ipv4-specific dst helpers for IPv6 bridge traffic.

Fixes: 34666d467cbf ("netfilter: bridge: move br_netfilter out of the core")
Cc: stable@kernel.org
Reported-by: Yuan Tan 
Reported-by: Yifan Wu 
Reported-by: Juefei Pu 
Reported-by: Xin Liu 
Signed-off-by: Haoze Xie 
Signed-off-by: Ren Wei 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman