sco_sock_connect() copies the destination address into sco_pi(sk)->dst
under lock_sock(), then releases the lock and calls sco_connect(),
which reads dst, src, setting, and codec without holding lock_sock() in
hci_get_route() and hci_connect_sco().
These fields may be modified concurrently by connect(), bind(), or
setsockopt() on the same socket, resulting in data-races reported by
KCSAN.
Fix this by snapshotting dst, src, setting, and codec under lock_sock()
at the start of sco_connect() before passing them to hci_get_route()
and hci_connect_sco().
BUG: KCSAN: data-race in memcmp+0x45/0xb0
race at unknown origin, with read to 0xffff88800e6b0dd0 of 1 bytes
by task 315 on cpu 0:
memcmp+0x45/0xb0
hci_connect_acl+0x1b7/0x6b0
hci_connect_sco+0x4d/0xb30
sco_sock_connect+0x27b/0xd60
__sys_connect_file+0xbd/0xe0
__sys_connect+0xe0/0x110
__x64_sys_connect+0x40/0x50
x64_sys_call+0xcad/0x1c60
do_syscall_64+0x133/0x590
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Fixes: 9a8ec9e8eb ("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm")
Signed-off-by: SeungJu Cheon <suunj1331@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
bt_accept_dequeue() unlinks a not-yet-accepted child from the parent
accept queue and release_sock()s it before returning, so the returned
sk has no caller reference and is unlocked.
l2cap_sock_cleanup_listen() walks these children on listening-socket
close. A concurrent HCI disconnect drives hci_rx_work ->
l2cap_conn_del() which runs l2cap_chan_del() + l2cap_sock_kill() and
frees the child sk and its l2cap_chan; cleanup_listen() then uses both:
BUG: KASAN: slab-use-after-free in l2cap_sock_kill
l2cap_sock_kill / l2cap_sock_cleanup_listen / __x64_sys_close
Freed by: l2cap_conn_del -> l2cap_sock_close_cb -> l2cap_sock_kill
This is distinct from the two fixes already in this area: commit
e83f5e24da ("Bluetooth: serialize accept_q access") serialises the
accept_q list/poll and takes temporary refs inside bt_accept_dequeue(),
and CVE-2025-39860 serialises the userspace close()/accept() race by
calling cleanup_listen() under lock_sock() in l2cap_sock_release().
Neither covers l2cap_conn_del() running from hci_rx_work, so this UAF
still reproduces on current bluetooth/master.
Take the reference at the source: bt_accept_dequeue() does sock_hold()
while sk is still locked, before release_sock(); callers sock_put().
cleanup_listen() pins the chan with l2cap_chan_hold_unless_zero() under
a brief child sk lock (serialising vs l2cap_sock_teardown_cb()), drops
it before l2cap_chan_lock(), and skips a duplicate l2cap_sock_kill() on
SOCK_DEAD. conn->lock is not taken here: cleanup_listen() runs under
the parent sk lock and that would invert
conn->lock -> chan->lock -> sk_lock (lockdep).
KASAN/SMP: an unprivileged listen/close vs HCI-disconnect race produced
12 use-after-free reports per run before this change; 0, and no lockdep
report, over 1600+ raced iterations after it on bluetooth/master.
Fixes: 15f02b9105 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode")
Cc: stable@vger.kernel.org
Reported-by: Siwei Zhang <oss@fourdim.xyz>
Reviewed-by: Siwei Zhang <oss@fourdim.xyz>
Signed-off-by: Safa Karakuş <safa.karakus@secunnix.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sk deref in sco_conn_ready must be done either under conn->lock, or
holding a refcount, to avoid concurrent close. conn->sk and parent sk is
currently accessed without either, and without checking parent->sk_state:
[Task 1] [Task 2]
sco_sock_release
sco_conn_ready
sk = conn->sk
lock_sock(sk)
conn->sk = NULL
lock_sock(sk)
release_sock(sk)
sco_sock_kill(sk)
UAF on sk deref
and similarly for access to sco_get_sock_listen() return value.
Fix possible UAF by holding sk refcount in sco_conn_ready() and making
sco_get_sock_listen() increase refcount. Also recheck after lock_sock
that the socket is still valid. Adjust conn->sk locking so it's
protected also by lock_sock() of the associated socket if any.
Fixes: 27c24fda62 ("Bluetooth: switch to lock_sock in SCO")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sco_conn_ready calls sleeping functions under conn->lock spinlock.
The critical section can be reduced: conn->hcon is modified only with
hdev->lock held. It is guaranteed to be held in sco_conn_ready, so
conn->lock is not needed to guard it.
Move taking conn->lock after lock_sock(parent). This also follows the
lock ordering lock_sock() > conn->lock elsewhere in the file.
Fixes: 27c24fda62 ("Bluetooth: switch to lock_sock in SCO")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
copy_struct_from_sockptr() fill 'buffer' in
sco_sock_setsockopt() with zeros, so there's no
real problem.
But it actually looks strange to do this,
without checking all of codecs->codecs[0]
really comes from userspace:
sco_pi(sk)->codec = codecs->codecs[0];
As only optlen < sizeof(struct bt_codecs) is checked
and codecs->num_codecs is not checked against != 1,
but only <= 1, and the space for the additional struct bt_codec
is not checked.
Note I don't understand bluetooth and I didn't do any runtime
tests with this! I just found it when debugging a problem
in copy_struct_from_sockptr().
I just added this to check the size is as expected:
BUILD_BUG_ON(struct_size(codecs, codecs, 0) != 1);
BUILD_BUG_ON(struct_size(codecs, codecs, 1) != 8);
And made sure it still compiles using this:
make CF=-D__CHECK_ENDIAN__ W=1ce C=1 net/bluetooth/sco.o
Fixes: 3e643e4efa ("Bluetooth: Improve setsockopt() handling of malformed user input")
Cc: Michal Luczaj <mhal@rbox.co>
Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Cc: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Cc: Marcel Holtmann <marcel@holtmann.org>
Cc: David Wei <dw@davidwei.uk>
Cc: linux-bluetooth@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sco_sock_connect() checks sk_state and sk_type without holding
the socket lock. Two concurrent connect() syscalls on the same
socket can both pass the check and enter sco_connect(), leading
to use-after-free.
The buggy scenario involves three participants and was confirmed
with additional logging instrumentation:
Thread A (connect): HCI disconnect: Thread B (connect):
sco_sock_connect(sk) sco_sock_connect(sk)
sk_state==BT_OPEN sk_state==BT_OPEN
(pass, no lock) (pass, no lock)
sco_connect(sk): sco_connect(sk):
hci_dev_lock hci_dev_lock
hci_connect_sco <- blocked
-> hcon1
sco_conn_add->conn1
lock_sock(sk)
sco_chan_add:
conn1->sk = sk
sk->conn = conn1
sk_state=BT_CONNECT
release_sock
hci_dev_unlock
hci_dev_lock
sco_conn_del:
lock_sock(sk)
sco_chan_del:
sk->conn=NULL
conn1->sk=NULL
sk_state=
BT_CLOSED
SOCK_ZAPPED
release_sock
hci_dev_unlock
(unblocked)
hci_connect_sco
-> hcon2
sco_conn_add
-> conn2
lock_sock(sk)
sco_chan_add:
sk->conn=conn2
sk_state=
BT_CONNECT
// zombie sk!
release_sock
hci_dev_unlock
Thread B revives a BT_CLOSED + SOCK_ZAPPED socket back to
BT_CONNECT. Subsequent cleanup triggers double sock_put() and
use-after-free. Meanwhile conn1 is leaked as it was orphaned
when sco_conn_del() cleared the association.
Fix this by:
- Moving lock_sock() before the sk_state/sk_type checks in
sco_sock_connect() to serialize concurrent connect attempts
- Fixing the sk_type != SOCK_SEQPACKET check to actually
return the error instead of just assigning it
- Adding a state re-check in sco_connect() after lock_sock()
to catch state changes during the window between the locks
- Adding sco_pi(sk)->conn check in sco_chan_add() to prevent
double-attach of a socket to multiple connections
- Adding hci_conn_drop() on sco_chan_add failure to prevent
HCI connection leaks
Fixes: 9a8ec9e8eb ("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm")
Signed-off-by: Cen Zhang <zzzccc427@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sco_recv_frame() reads conn->sk under sco_conn_lock() but immediately
releases the lock without holding a reference to the socket. A concurrent
close() can free the socket between the lock release and the subsequent
sk->sk_state access, resulting in a use-after-free.
Other functions in the same file (sco_sock_timeout(), sco_conn_del())
correctly use sco_sock_hold() to safely hold a reference under the lock.
Fix by using sco_sock_hold() to take a reference before releasing the
lock, and adding sock_put() on all exit paths.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
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
...
When TX timestamping is enabled via SO_TIMESTAMPING, SKBs may be queued
into sk_error_queue and will stay there until consumed. If userspace never
gets to read the timestamps, or if the controller is removed unexpectedly,
these SKBs will leak.
Fix by adding skb_queue_purge() calls for sk_error_queue in affected
bluetooth destructors. RFCOMM does not currently use sk_error_queue.
Fixes: 134f4b39df ("Bluetooth: add support for skb TX SND/COMPLETION timestamping")
Reported-by: syzbot+7ff4013eabad1407b70a@syzkaller.appspotmail.com
Closes: https://syzbot.org/bug?extid=7ff4013eabad1407b70a
Cc: stable@vger.kernel.org
Signed-off-by: Heitor Alves de Siqueira <halves@igalia.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This was done entirely with mindless brute force, using
git grep -l '\<k[vmz]*alloc_objs*(.*, GFP_KERNEL)' |
xargs sed -i 's/\(alloc_objs*(.*\), GFP_KERNEL)/\1)/'
to convert the new alloc_obj() users that had a simple GFP_KERNEL
argument to just drop that argument.
Note that due to the extreme simplicity of the scripting, any slightly
more complex cases spread over multiple lines would not be triggered:
they definitely exist, but this covers the vast bulk of the cases, and
the resulting diff is also then easier to check automatically.
For the same reason the 'flex' versions will be done as a separate
conversion.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the result of running the Coccinelle script from
scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to
avoid scalar types (which need careful case-by-case checking), and
instead replace kmalloc-family calls that allocate struct or union
object instances:
Single allocations: kmalloc(sizeof(TYPE), ...)
are replaced with: kmalloc_obj(TYPE, ...)
Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...)
are replaced with: kmalloc_objs(TYPE, COUNT, ...)
Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...)
are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...)
(where TYPE may also be *VAR)
The resulting allocations no longer return "void *", instead returning
"TYPE *".
Signed-off-by: Kees Cook <kees@kernel.org>
The hdev lock/lookup/unlock/use pattern in the packet RX path doesn't
ensure hci_conn* is not concurrently modified/deleted. This locking
appears to be leftover from before conn_hash started using RCU
commit bf4c632524 ("Bluetooth: convert conn hash to RCU")
and not clear if it had purpose since then.
Currently, there are code paths that delete hci_conn* from elsewhere
than the ordered hdev->workqueue where the RX work runs in. E.g.
commit 5af1f84ed1 ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync")
introduced some of these, and there probably were a few others before
it. It's better to do the locking so that even if these run
concurrently no UAF is possible.
Move the lookup of hci_conn and associated socket-specific conn to
protocol recv handlers, and do them within a single critical section
to cover hci_conn* usage and lookup.
syzkaller has reported a crash that appears to be this issue:
[Task hdev->workqueue] [Task 2]
hci_disconnect_all_sync
l2cap_recv_acldata(hcon)
hci_conn_get(hcon)
hci_abort_conn_sync(hcon)
hci_dev_lock
hci_dev_lock
hci_conn_del(hcon)
v-------------------------------- hci_dev_unlock
hci_conn_put(hcon)
conn = hcon->l2cap_data (UAF)
Fixes: 5af1f84ed1 ("Bluetooth: hci_sync: Fix UAF on hci_abort_conn_sync")
Reported-by: syzbot+d32d77220b92eddd89ad@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d32d77220b92eddd89ad
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Update all struct proto_ops connect() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-3-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Update all struct proto_ops bind() callback function prototypes from
"struct sockaddr *" to "struct sockaddr_unsized *" to avoid lying to the
compiler about object sizes. Calls into struct proto handlers gain casts
that will be removed in the struct proto conversion patch.
No binary changes expected.
Signed-off-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20251104002617.2752303-2-kees@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Followup of commit 285975dd67 ("net: annotate data-races around
sk->sk_{rcv|snd}timeo").
Remove lock_sock()/release_sock() from sock_set_sndtimeo(),
and add READ_ONCE()/WRITE_ONCE() where it is needed.
Also SO_SNDTIMEO_OLD and SO_SNDTIMEO_NEW can call sock_set_timeout()
without holding the socket lock.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250620155536.335520-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Support TX timestamping in SCO sockets.
Not available for hdevs without SCO_FLOWCTL.
Support MSG_ERRQUEUE in SCO recvmsg.
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
sco_conn refcount shall not be incremented a second time if the sk
already owns the refcount, so hold only when adding new chan.
Add sco_conn_hold() for clarity, as refcnt is never zero here due to the
sco_conn_add().
Fixes SCO socket shutdown not actually closing the SCO connection.
Fixes: ed95885549 ("Bluetooth: SCO: remove the redundant sco_conn_put")
Signed-off-by: Pauli Virtanen <pav@iki.fi>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The voice setting is used by sco_connect() or sco_conn_defer_accept()
after being set by sco_sock_setsockopt().
The PCM part of the voice setting is used for offload mode through PCM
chipset port.
This commits add support for mSBC 16 bits offloading, i.e. audio data
not transported over HCI.
The BCM4349B1 supports 16 bits transparent data on its I2S port.
If BT_VOICE_TRANSPARENT is used when accepting a SCO connection, this
gives only garbage audio while using BT_VOICE_TRANSPARENT_16BIT gives
correct audio.
This has been tested with connection to iPhone 14 and Samsung S24.
Fixes: ad10b1a487 ("Bluetooth: Add Bluetooth socket voice option")
Signed-off-by: Frédéric Danis <frederic.danis@collabora.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
The bt_copy_from_sockptr() return value is being misinterpreted by most
users: a non-zero result is mistakenly assumed to represent an error code,
but actually indicates the number of bytes that could not be copied.
Remove bt_copy_from_sockptr() and adapt callers to use
copy_safe_from_sockptr().
For sco_sock_setsockopt() (case BT_CODEC) use copy_struct_from_sockptr() to
scrub parts of uninitialized buffer.
Opportunistically, rename `len` to `optlen` in hci_sock_setsockopt_old()
and hci_sock_setsockopt().
Fixes: 51eda36d33 ("Bluetooth: SCO: Fix not validating setsockopt user input")
Fixes: a97de7bff1 ("Bluetooth: RFCOMM: Fix not validating setsockopt user input")
Fixes: 4f3951242a ("Bluetooth: L2CAP: Fix not validating setsockopt user input")
Fixes: 9e8742cdfc ("Bluetooth: ISO: Fix not validating setsockopt user input")
Fixes: b2186061d6 ("Bluetooth: hci_sock: Fix not validating setsockopt user input")
Reviewed-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: David Wei <dw@davidwei.uk>
Signed-off-by: Michal Luczaj <mhal@rbox.co>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
This make use of kref to keep track of reference of sco_conn which
allows better tracking of its lifetime with usage of things like
kref_get_unless_zero in a similar way as used in l2cap_chan.
In addition to it remove call to sco_sock_set_timer on __sco_sock_close
since at that point it is useless to set a timer as the sk will be freed
there is nothing to be done in sco_sock_timeout.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
