kernel/linux.git/net/bluetooth/iso.c, branch v6.6.142

Bluetooth: ISO: drop ISO_END frames received without prior ISO_START

2026-06-01T15:43:06+00:00

commit 84c24fb151fc1179355296d7ff29129ac7c42129 upstream. ISO data PDUs carry a packet-boundary flag indicating START, CONT, END or SINGLE. The ISO_CONT branch of iso_recv() guards against a missing ISO_START by checking conn->rx_len before touching conn->rx_skb, but ISO_END does not. If a peer sends an ISO_END as the first packet on a fresh ISO connection, conn->rx_skb is still NULL and conn->rx_len is zero, so skb_put(conn->rx_skb, ...) dereferences NULL and oopses. For BIS, where receivers sync to a broadcaster without pairing, any broadcaster on the air can trigger this. Mirror the ISO_CONT check at the top of ISO_END so a stray end fragment is logged and dropped instead of crashing the host. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: David Carlier Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: fix UAF in l2cap_sock_cleanup_listen() vs l2cap_conn_del()

2026-06-01T15:43:06+00:00

commit ab1513597c6cf17cd1ad2a21e3b045421b48e022 upstream. 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 e83f5e24da741 ("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: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Cc: stable@vger.kernel.org Reported-by: Siwei Zhang Reviewed-by: Siwei Zhang Signed-off-by: Safa Karakuş Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: ISO: Fix another instance of dst_type handling

2025-11-24T09:29:14+00:00

[ Upstream commit c403da5e98b04a2aec9cfb25cbeeb28d7ce29975 ] Socket dst_type cannot be directly assigned to hci_conn->type since there domain is different which may lead to the wrong address type being used. Fixes: 6a5ad251b7cd ("Bluetooth: ISO: Fix possible circular locking dependency") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: don't leak skb in ISO_CONT RX

2025-10-15T09:58:05+00:00

[ Upstream commit 5bf863f4c5da055c1eb08887ae4f26d99dbc4aac ] For ISO_CONT RX, the data from skb is copied to conn->rx_skb, but the skb is leaked. Free skb after copying its data. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: Fix possible UAF on iso_conn_free

2025-10-15T09:58:05+00:00

[ Upstream commit 9950f095d6c875dbe0c9ebfcf972ec88fdf26fc8 ] This attempt to fix similar issue to sco_conn_free where if the conn->sk is not set to NULL may lead to UAF on iso_conn_free. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Revert "Bluetooth: hci_core: Fix sleeping function called from invalid context"

2025-03-22T19:50:38+00:00

[ Upstream commit ab6ab707a4d060a51c45fc13e3b2228d5f7c0b87 ] This reverts commit 4d94f05558271654670d18c26c912da0c1c15549 which has problems (see [1]) and is no longer needed since 581dd2dc168f ("Bluetooth: hci_event: Fix using rcu_read_(un)lock while iterating") has reworked the code where the original bug has been found. [1] Link: https://lore.kernel.org/linux-bluetooth/877c55ci1r.wl-tiwai@suse.de/T/#t Fixes: 4d94f0555827 ("Bluetooth: hci_core: Fix sleeping function called from invalid context") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: hci_core: Fix sleeping function called from invalid context

2025-01-09T12:32:05+00:00

[ Upstream commit 4d94f05558271654670d18c26c912da0c1c15549 ] This reworks hci_cb_list to not use mutex hci_cb_list_lock to avoid bugs like the bellow: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:585 in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 5070, name: kworker/u9:2 preempt_count: 0, expected: 0 RCU nest depth: 1, expected: 0 4 locks held by kworker/u9:2/5070: #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3229 [inline] #0: ffff888015be3948 ((wq_completion)hci0#2){+.+.}-{0:0}, at: process_scheduled_works+0x8e0/0x1770 kernel/workqueue.c:3335 #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3230 [inline] #1: ffffc90003b6fd00 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0x91b/0x1770 kernel/workqueue.c:3335 #2: ffff8880665d0078 (&hdev->lock){+.+.}-{3:3}, at: hci_le_create_big_complete_evt+0xcf/0xae0 net/bluetooth/hci_event.c:6914 #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline] #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline] #3: ffffffff8e132020 (rcu_read_lock){....}-{1:2}, at: hci_le_create_big_complete_evt+0xdb/0xae0 net/bluetooth/hci_event.c:6915 CPU: 0 PID: 5070 Comm: kworker/u9:2 Not tainted 6.8.0-syzkaller-08073-g480e035fc4c7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Workqueue: hci0 hci_rx_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 __might_resched+0x5d4/0x780 kernel/sched/core.c:10187 __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0xc1/0xd70 kernel/locking/mutex.c:752 hci_connect_cfm include/net/bluetooth/hci_core.h:2004 [inline] hci_le_create_big_complete_evt+0x3d9/0xae0 net/bluetooth/hci_event.c:6939 hci_event_func net/bluetooth/hci_event.c:7514 [inline] hci_event_packet+0xa53/0x1540 net/bluetooth/hci_event.c:7569 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4171 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 Reported-by: syzbot+2fb0835e0c9cefc34614@syzkaller.appspotmail.com Tested-by: syzbot+2fb0835e0c9cefc34614@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=2fb0835e0c9cefc34614 Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: iso: Fix recursive locking warning

2024-12-19T17:11:33+00:00

[ Upstream commit 9bde7c3b3ad0e1f39d6df93dd1c9caf63e19e50f ] This updates iso_sock_accept to use nested locking for the parent socket, to avoid lockdep warnings caused because the parent and child sockets are locked by the same thread: [ 41.585683] ============================================ [ 41.585688] WARNING: possible recursive locking detected [ 41.585694] 6.12.0-rc6+ #22 Not tainted [ 41.585701] -------------------------------------------- [ 41.585705] iso-tester/3139 is trying to acquire lock: [ 41.585711] ffff988b29530a58 (sk_lock-AF_BLUETOOTH) at: bt_accept_dequeue+0xe3/0x280 [bluetooth] [ 41.585905] but task is already holding lock: [ 41.585909] ffff988b29533a58 (sk_lock-AF_BLUETOOTH) at: iso_sock_accept+0x61/0x2d0 [bluetooth] [ 41.586064] other info that might help us debug this: [ 41.586069] Possible unsafe locking scenario: [ 41.586072] CPU0 [ 41.586076] ---- [ 41.586079] lock(sk_lock-AF_BLUETOOTH); [ 41.586086] lock(sk_lock-AF_BLUETOOTH); [ 41.586093] *** DEADLOCK *** [ 41.586097] May be due to missing lock nesting notation [ 41.586101] 1 lock held by iso-tester/3139: [ 41.586107] #0: ffff988b29533a58 (sk_lock-AF_BLUETOOTH) at: iso_sock_accept+0x61/0x2d0 [bluetooth] Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Iulia Tanasescu Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: ISO: Reassociate a socket with an active BIS

2024-12-19T17:11:33+00:00

[ Upstream commit fa224d0c094a458e9ebf5ea9b1c696136b7af427 ] For ISO Broadcast, all BISes from a BIG have the same lifespan - they cannot be created or terminated independently from each other. This links together all BIS hcons that are part of the same BIG, so all hcons are kept alive as long as the BIG is active. If multiple BIS sockets are opened for a BIG handle, and only part of them are closed at some point, the associated hcons will be marked as open. If new sockets will later be opened for the same BIG, they will be reassociated with the open BIS hcons. All BIS hcons will be cleaned up and the BIG will be terminated when the last BIS socket is closed from userspace. Signed-off-by: Iulia Tanasescu Signed-off-by: Luiz Augusto von Dentz Stable-dep-of: 581dd2dc168f ("Bluetooth: hci_event: Fix using rcu_read_(un)lock while iterating") Signed-off-by: Sasha Levin

Bluetooth: ISO: Fix UAF on iso_sock_timeout

2024-11-01T00:58:30+00:00

[ Upstream commit 246b435ad668596aa0e2bbb9d491b6413861211a ] conn->sk maybe have been unlinked/freed while waiting for iso_conn_lock so this checks if the conn->sk is still valid by checking if it part of iso_sk_list. Fixes: ccf74f2390d6 ("Bluetooth: Add BTPROTO_ISO socket type") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin