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

Bluetooth: serialize accept_q access

2026-06-01T15:43:07+00:00

commit e83f5e24da741fa9405aeeff00b08c5ee7c37b88 upstream. bt_sock_poll() walks the accept queue without synchronization, while child teardown can unlink the same socket and drop its last reference. The unsynchronized accept queue walk has existed since the initial Bluetooth import. Protect accept_q with a dedicated lock for queue updates and polling. Also rework bt_accept_dequeue() to take temporary child references under the queue lock before dropping it and locking the child socket. Fixes: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Reported-by: Jann Horn Reported-by: Yuan Tan Reported-by: Yifan Wu Reported-by: Juefei Pu Reported-by: Xin Liu Signed-off-by: Jiexun Wang Signed-off-by: Ren Wei Signed-off-by: Jiexun Wang Reviewed-by: Jann Horn Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: MGMT: validate Add Extended Advertising Data length

2026-06-01T15:43:07+00:00

commit d3f7d17960ed50df3a6709c5158caff989c8c905 upstream. MGMT_OP_ADD_EXT_ADV_DATA is registered as a variable-length command, with MGMT_ADD_EXT_ADV_DATA_SIZE as the fixed header size. The handler then uses cp->adv_data_len and cp->scan_rsp_len to validate and copy cp->data, but it never checks that those bytes are part of the mgmt command payload. A short command can therefore make add_ext_adv_data() pass an out-of-bounds pointer into tlv_data_is_valid(). If the bytes beyond the command buffer are addressable, they can also be copied into the advertising instance as scan response data, where the caller can read them back via MGMT_OP_GET_ADV_INSTANCE. The trigger requires CAP_NET_ADMIN in the initial user namespace; KASAN reports an 8-byte slab-out-of-bounds read. Reject commands whose length does not match the fixed header plus both advertising data lengths before parsing cp->data. Fixes: 12410572833a ("Bluetooth: Break add adv into two mgmt commands") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Signed-off-by: Michael Bommarito Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

Bluetooth: bnep: Fix UAF read of dev->name

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

commit 59e932ded949fa6f0340bf7c6d7818f962fa4fd2 upstream. bnep_add_connection() needs to keep holding the bnep_session_sem while reading dev->name (just like bnep_get_connlist() does); otherwise the bnep_session() thread can concurrently free the net_device, which can for example be triggered by a concurrent bnep_del_connection(). (This UAF is fairly uninteresting from a security perspective; calling bnep_add_connection() requires passing a capable(CAP_NET_ADMIN) check. It also requires completely tearing down a netdev during a fairly tight race window.) Cc: stable@vger.kernel.org Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Jann Horn Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman

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: l2cap: Add missing chan lock in l2cap_ecred_reconf_rsp

2026-05-23T11:03:09+00:00

[ Upstream commit 42776497cdbc9a665b384a6dcb85f0d4bd927eab ] l2cap_ecred_reconf_rsp() calls l2cap_chan_del() without holding l2cap_chan_lock(). Every other l2cap_chan_del() caller in the file acquires the lock first. A remote BLE device can send a crafted L2CAP ECRED reconfiguration response to corrupt the channel list while another thread is iterating it. Add l2cap_chan_hold() and l2cap_chan_lock() before l2cap_chan_del(), and l2cap_chan_unlock() and l2cap_chan_put() after, matching the pattern used in l2cap_ecred_conn_rsp() and l2cap_conn_del(). Fixes: 15f02b910562 ("Bluetooth: L2CAP: Add initial code for Enhanced Credit Based Mode") Signed-off-by: Dudu Lu Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: fix locking in hci_conn_request_evt() with HCI_PROTO_DEFER

2026-05-23T11:03:09+00:00

[ Upstream commit 5c7209a341ff2ac338b2b0375c34a307b37c9ac2 ] When protocol sets HCI_PROTO_DEFER, hci_conn_request_evt() calls hci_connect_cfm(conn) without hdev->lock. Generally hci_connect_cfm() assumes it is held, and if conn is deleted concurrently -> UAF. Only SCO and ISO set HCI_PROTO_DEFER and only for defer setup listen, and HCI_EV_CONN_REQUEST is not generated for ISO. In the non-deferred listening socket code paths, hci_connect_cfm(conn) is called with hdev->lock held. Fix by holding the lock. Fixes: 70c464256310 ("Bluetooth: Refactor connection request handling") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin

Bluetooth: L2CAP: Fix printing wrong information if SDU length exceeds MTU

2026-05-23T11:03:09+00:00

[ Upstream commit 15bf35a660eb82a49f8397fc3d3acada8dae13db ] The code was printing skb->len and sdu_len in the places where it should be sdu_len and chan->imtu respectively to match the if conditions. Link: https://lore.kernel.org/linux-bluetooth/20260315132013.75ab40c5@kernel.org/T/#m1418f9c82eeff8510c1beaa21cf53af20db96c06 Fixes: e1d9a6688986 ("Bluetooth: LE L2CAP: Disconnect if received packet's SDU exceeds IMTU") Signed-off-by: Luiz Augusto von Dentz Reviewed-by: Paul Menzel Signed-off-by: Sasha Levin

Bluetooth: MGMT: Fix dangling pointer on mgmt_add_adv_patterns_monitor_complete

2026-05-17T15:13:54+00:00

commit 5f5fa4cd35f707344f65ce9e225b6528691dbbaa upstream. This fixes the condition checking so mgmt_pending_valid is executed whenever status != -ECANCELED otherwise calling mgmt_pending_free(cmd) would kfree(cmd) without unlinking it from the list first, leaving a dangling pointer. Any subsequent list traversal (e.g., mgmt_pending_foreach during __mgmt_power_off, or another mgmt_pending_valid call) would dereference freed memory. Link: https://lore.kernel.org/linux-bluetooth/20260315132013.75ab40c5@kernel.org/T/#m1418f9c82eeff8510c1beaa21cf53af20db96c06 Fixes: 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") Signed-off-by: Luiz Augusto von Dentz Reviewed-by: Paul Menzel Signed-off-by: Greg Kroah-Hartman

Bluetooth: MGMT: Fix memory leak in set_ssp_complete

2026-05-17T15:13:54+00:00

commit 1b9c17fd0a7fdcbe69ec5d6fe8e50bc5ed7f01f2 upstream. Fix memory leak in set_ssp_complete() where mgmt_pending_cmd structures are not freed after being removed from the pending list. Commit 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") replaced mgmt_pending_foreach() calls with individual command handling but missed adding mgmt_pending_free() calls in both error and success paths of set_ssp_complete(). Other completion functions like set_le_complete() were fixed correctly in the same commit. This causes a memory leak of the mgmt_pending_cmd structure and its associated parameter data for each SSP command that completes. Add the missing mgmt_pending_free(cmd) calls in both code paths to fix the memory leak. Also fix the same issue in set_advertising_complete(). Fixes: 302a1f674c00 ("Bluetooth: MGMT: Fix possible UAFs") Signed-off-by: Jianpeng Chang Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Greg Kroah-Hartman