kernel/linux.git/net/bluetooth, branch v6.6.148

Bluetooth: RFCOMM: Fix session UAF in set_termios

2026-08-03T09:15:28+00:00

commit c783399efc22d035443f1dfbf2a09bf9562aaa5e upstream. rfcomm_tty_set_termios() tests dlc->session without rfcomm_mutex and later passes the pointer to rfcomm_send_rpn(). The latter dereferences both session->initiator and session->sock. Meanwhile, krfcommd can unlink the DLC and free the session while holding rfcomm_mutex. The race can proceed as follows: TTY ioctl task krfcommd -------------- -------- load dlc->session enter rfcomm_send_rpn() lock rfcomm_mutex clear dlc->session free session unlock rfcomm_mutex read session->initiator KASAN reported: BUG: KASAN: slab-use-after-free in rfcomm_send_rpn+0x297/0x2a0 Read of size 4 at addr ffff88810012a850 by task poc/92 Call Trace: rfcomm_send_rpn+0x297/0x2a0 rfcomm_tty_set_termios+0x50d/0x850 tty_set_termios+0x596/0x950 set_termios+0x46a/0x6e0 tty_mode_ioctl+0x152/0xbd0 tty_ioctl+0x915/0x1240 __x64_sys_ioctl+0x134/0x1c0 Allocated by task 92: rfcomm_session_add+0x9e/0x2e0 rfcomm_dlc_open+0x8b1/0xe00 rfcomm_dev_activate+0x85/0x1a0 rfcomm_tty_open+0x90/0x280 Freed by task 68: kfree+0x131/0x3c0 rfcomm_session_del+0x119/0x180 rfcomm_run+0x737/0x4710 Add rfcomm_dlc_send_rpn(), which holds rfcomm_mutex while it verifies that the DLC is still attached and sends the RPN frame. Have the TTY path use the helper and drop its unlocked session check. This keeps the session valid through both the frame construction and socket send. Fixes: 3a5e903c09ae ("[Bluetooth]: Implement RFCOMM remote port negotiation") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_sync: Protect UUID list traversal

2026-08-03T09:15:28+00:00

commit e9027ffbf5a0f3c12ca8900822e884eae9f0821b upstream. The hci_sync conversion moved class-of-device and EIR generation from an HCI request built under hdev->lock to asynchronous command sync work. The worker holds hdev->req_lock, but that lock does not serialize access to hdev->uuids against add_uuid() and remove_uuid(), which update the list under hdev->lock. The following interleaving can therefore occur: CPU0 (command sync work) CPU1 (management socket) fetch uuid from the list list_del(&uuid->list) kfree(uuid) read uuid->size KASAN reports the resulting use-after-free: BUG: KASAN: slab-use-after-free in eir_create+0xb8f/0xee0 Read of size 1 at addr ffff88810dbd8620 by task kworker/u17:0/87 Workqueue: hci0 hci_cmd_sync_work Call Trace: eir_create+0xb8f/0xee0 hci_update_eir_sync+0x1c0/0x330 hci_cmd_sync_work+0x13c/0x290 process_one_work+0x63a/0x1070 worker_thread+0x45b/0xd10 Allocated by task 86: __kasan_kmalloc+0x8f/0xa0 add_uuid+0x18a/0x4b0 hci_sock_sendmsg+0x1033/0x1ea0 Freed by task 92: __kasan_slab_free+0x43/0x70 kfree+0x131/0x3c0 remove_uuid+0x25e/0x560 hci_sock_sendmsg+0x1033/0x1ea0 Hold hdev->lock while generating and committing the class-of-device and EIR snapshots. Release it before sending an HCI command, so controller waits do not happen under the device lock. This protects all UUID list walks in these paths and restores the serialization lost in the command sync conversion. Fixes: 161510ccf91c ("Bluetooth: hci_sync: Make use of hci_cmd_sync_queue set 1") Cc: stable@vger.kernel.org Signed-off-by: Chengfeng Ye Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: mgmt: hold reference for hci_conn in mgmt_pending_cmds

2026-08-03T09:15:15+00:00

[ Upstream commit da55f570191d5d72f10c607a7043b947eb05ea46 ] Dereferencing RCU-protected pointers outside critical sections is invalid and may lead to UAF. Use of hci_conn in hci_sync callbacks also needs to hold refcount to avoid UAF. Take appropriate locks for hci_conn lookups, and take refcount for hci_conn pointers stored in mgmt_pending_cmd so that the pointer stays valid. When accessing conn->state, ensure hdev->lock is held to avoid data race. Fixes: 7b445e220db9 ("Bluetooth: MGMT: Fix holding hci_conn reference while command is queued") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: mgmt: fix locking in unpair_device/disconnect_sync

2026-08-03T09:15:15+00:00

[ Upstream commit 16cd66443957e4ad42155c6fec401012f600c6f8 ] Dereferencing RCU-protected pointers outside critical sections is invalid and may lead to UAF. Take hdev->lock for hci_conn lookup and hci_abort_conn(). Don't use RCU to ensure the conn is fully initialized at this point. Fixes: 227a0cdf4a028 ("Bluetooth: MGMT: Fix not generating command complete for MGMT_OP_DISCONNECT") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

jiffies: Define secs_to_jiffies()

2026-07-24T14:03:53+00:00

commit b35108a51cf7bab58d7eace1267d7965978bcdb8 upstream. secs_to_jiffies() is defined in hci_event.c and cannot be reused by other call sites. Hoist it into the core code to allow conversion of the ~1150 usages of msecs_to_jiffies() that either: - use a multiplier value of 1000 or equivalently MSEC_PER_SEC, or - have timeouts that are denominated in seconds (i.e. end in 000) It's implemented as a macro to allow usage in static initializers. This will also allow conversion of yet more sites that use (sec * HZ) directly, and improve their readability. Suggested-by: Michael Kelley Signed-off-by: Easwar Hariharan Signed-off-by: Thomas Gleixner Reviewed-by: Luiz Augusto von Dentz Link: https://lore.kernel.org/all/20241030-open-coded-timeouts-v3-1-9ba123facf88@linux.microsoft.com Signed-off-by: Greg Kroah-Hartman

Bluetooth: 6lowpan: Fix using chan->conn as indication to no remote netdev

2026-07-24T14:03:53+00:00

commit d38eaf611839b85ade3dd3db309dbc8aaaaf0095 upstream. b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref") don't reset the chan->conn to NULL anymore making the bt# netdev not be remove once the last l2cap_chan_del is removed. Instead of restoring the original behavior this remove the logic of keeping the interface after the last channel is removed because it never worked as intended and the l2cap_chan_del always detach its l2cap_conn which results in always removing the channel anyway. Fixes: b66774b48dd9 ("Bluetooth: L2CAP: Fix UAF in channel timeout by holding conn ref") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: hci_sync: Fix attempting to send HCI_Disconnect to BIS handle

2026-07-24T14:03:53+00:00

commit 314d30b1508682e27c8a324096262c66f23455d9 upstream. BIS/PA connections do have their own cleanup proceedure which are performed by hci_conn_cleanup/bis_cleanup. Fixes: 23205562ffc8 ("Bluetooth: separate CIS_LINK and BIS_LINK link types") Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

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

2026-07-24T14:03:52+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: hci_sync: annotate data-races around hdev->req_status

2026-07-24T14:03:52+00:00

[ Upstream commit b6807cfc195ef99e1ac37b2e1e60df40295daa8c ] __hci_cmd_sync_sk() sets hdev->req_status under hdev->req_lock: hdev->req_status = HCI_REQ_PEND; However, several other functions read or write hdev->req_status without holding any lock: - hci_send_cmd_sync() reads req_status in hci_cmd_work (workqueue) - hci_cmd_sync_complete() reads/writes from HCI event completion - hci_cmd_sync_cancel() / hci_cmd_sync_cancel_sync() read/write - hci_abort_conn() reads in connection abort path Since __hci_cmd_sync_sk() runs on hdev->req_workqueue while hci_send_cmd_sync() runs on hdev->workqueue, these are different workqueues that can execute concurrently on different CPUs. The plain C accesses constitute a data race. Add READ_ONCE()/WRITE_ONCE() annotations on all concurrent accesses to hdev->req_status to prevent potential compiler optimizations that could affect correctness (e.g., load fusing in the wait_event condition or store reordering). Signed-off-by: Cen Zhang 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: separate CIS_LINK and BIS_LINK link types

2026-07-24T14:03:52+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