From a834a0b66ec6fb743377201a0f4229bb2503f4ce Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Wed, 25 Mar 2026 21:07:46 +0200 Subject: [PATCH 01/14] Bluetooth: hci_sync: call destroy in hci_cmd_sync_run if immediate hci_cmd_sync_run() may run the work immediately if called from existing sync work (otherwise it queues a new sync work). In this case it fails to call the destroy() function. On immediate run, make it behave same way as if item was queued successfully: call destroy, and return 0. The only callsite is hci_abort_conn() via hci_cmd_sync_run_once(), and this changes its return value. However, its return value is not used except as the return value for hci_disconnect(), and nothing uses the return value of hci_disconnect(). Hence there should be no behavior change anywhere. Fixes: c898f6d7b093b ("Bluetooth: hci_sync: Introduce hci_cmd_sync_run/hci_cmd_sync_run_once") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_sync.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 45d16639874a..6283a4df78b0 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -801,8 +801,15 @@ int hci_cmd_sync_run(struct hci_dev *hdev, hci_cmd_sync_work_func_t func, return -ENETDOWN; /* If on cmd_sync_work then run immediately otherwise queue */ - if (current_work() == &hdev->cmd_sync_work) - return func(hdev, data); + if (current_work() == &hdev->cmd_sync_work) { + int err; + + err = func(hdev, data); + if (destroy) + destroy(hdev, data, err); + + return 0; + } return hci_cmd_sync_submit(hdev, func, data, destroy); } From 8a5b0135d4a5d9683203a3d9a12a711ccec5936b Mon Sep 17 00:00:00 2001 From: Cen Zhang Date: Thu, 26 Mar 2026 23:16:45 +0800 Subject: [PATCH 02/14] Bluetooth: SCO: fix race conditions in sco_sock_connect() 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: 9a8ec9e8ebb5 ("Bluetooth: SCO: Fix possible circular locking dependency on sco_connect_cfm") Signed-off-by: Cen Zhang Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/sco.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-) diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c index 584e059de20a..b84587811ef4 100644 --- a/net/bluetooth/sco.c +++ b/net/bluetooth/sco.c @@ -298,7 +298,7 @@ static int sco_chan_add(struct sco_conn *conn, struct sock *sk, int err = 0; sco_conn_lock(conn); - if (conn->sk) + if (conn->sk || sco_pi(sk)->conn) err = -EBUSY; else __sco_chan_add(conn, sk, parent); @@ -353,9 +353,20 @@ static int sco_connect(struct sock *sk) lock_sock(sk); + /* Recheck state after reacquiring the socket lock, as another + * thread may have changed it (e.g., closed the socket). + */ + if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) { + release_sock(sk); + hci_conn_drop(hcon); + err = -EBADFD; + goto unlock; + } + err = sco_chan_add(conn, sk, NULL); if (err) { release_sock(sk); + hci_conn_drop(hcon); goto unlock; } @@ -656,13 +667,18 @@ static int sco_sock_connect(struct socket *sock, struct sockaddr_unsized *addr, addr->sa_family != AF_BLUETOOTH) return -EINVAL; - if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) - return -EBADFD; - - if (sk->sk_type != SOCK_SEQPACKET) - err = -EINVAL; - lock_sock(sk); + + if (sk->sk_state != BT_OPEN && sk->sk_state != BT_BOUND) { + release_sock(sk); + return -EBADFD; + } + + if (sk->sk_type != SOCK_SEQPACKET) { + release_sock(sk); + return -EINVAL; + } + /* Set destination address and psm */ bacpy(&sco_pi(sk)->dst, &sa->sco_bdaddr); release_sock(sk); From 2b2bf47cd75518c36fa2d41380e4a40641cc89cd Mon Sep 17 00:00:00 2001 From: Oleh Konko Date: Thu, 26 Mar 2026 17:31:24 +0000 Subject: [PATCH 03/14] Bluetooth: hci_event: move wake reason storage into validated event handlers hci_store_wake_reason() is called from hci_event_packet() immediately after stripping the HCI event header but before hci_event_func() enforces the per-event minimum payload length from hci_ev_table. This means a short HCI event frame can reach bacpy() before any bounds check runs. Rather than duplicating skb parsing and per-event length checks inside hci_store_wake_reason(), move wake-address storage into the individual event handlers after their existing event-length validation has succeeded. Convert hci_store_wake_reason() into a small helper that only stores an already-validated bdaddr while the caller holds hci_dev_lock(). Use the same helper after hci_event_func() with a NULL address to preserve the existing unexpected-wake fallback semantics when no validated event handler records a wake address. Annotate the helper with __must_hold(&hdev->lock) and add lockdep_assert_held(&hdev->lock) so future call paths keep the lock contract explicit. Call the helper from hci_conn_request_evt(), hci_conn_complete_evt(), hci_sync_conn_complete_evt(), le_conn_complete_evt(), hci_le_adv_report_evt(), hci_le_ext_adv_report_evt(), hci_le_direct_adv_report_evt(), hci_le_pa_sync_established_evt(), and hci_le_past_received_evt(). Fixes: 2f20216c1d6f ("Bluetooth: Emit controller suspend and resume events") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_event.c | 94 +++++++++++++++------------------------ 1 file changed, 35 insertions(+), 59 deletions(-) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 286529d2e554..81d2f9a3eec9 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -80,6 +80,10 @@ static void *hci_le_ev_skb_pull(struct hci_dev *hdev, struct sk_buff *skb, return data; } +static void hci_store_wake_reason(struct hci_dev *hdev, + const bdaddr_t *bdaddr, u8 addr_type) + __must_hold(&hdev->lock); + static u8 hci_cc_inquiry_cancel(struct hci_dev *hdev, void *data, struct sk_buff *skb) { @@ -3111,6 +3115,7 @@ static void hci_conn_complete_evt(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "status 0x%2.2x", status); hci_dev_lock(hdev); + hci_store_wake_reason(hdev, &ev->bdaddr, BDADDR_BREDR); /* Check for existing connection: * @@ -3274,6 +3279,10 @@ static void hci_conn_request_evt(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "bdaddr %pMR type 0x%x", &ev->bdaddr, ev->link_type); + hci_dev_lock(hdev); + hci_store_wake_reason(hdev, &ev->bdaddr, BDADDR_BREDR); + hci_dev_unlock(hdev); + /* Reject incoming connection from device with same BD ADDR against * CVE-2020-26555 */ @@ -5021,6 +5030,7 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "status 0x%2.2x", status); hci_dev_lock(hdev); + hci_store_wake_reason(hdev, &ev->bdaddr, BDADDR_BREDR); conn = hci_conn_hash_lookup_ba(hdev, ev->link_type, &ev->bdaddr); if (!conn) { @@ -5713,6 +5723,7 @@ static void le_conn_complete_evt(struct hci_dev *hdev, u8 status, int err; hci_dev_lock(hdev); + hci_store_wake_reason(hdev, bdaddr, bdaddr_type); /* All controllers implicitly stop advertising in the event of a * connection, so ensure that the state bit is cleared. @@ -6005,6 +6016,7 @@ static void hci_le_past_received_evt(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "status 0x%2.2x", ev->status); hci_dev_lock(hdev); + hci_store_wake_reason(hdev, &ev->bdaddr, ev->bdaddr_type); hci_dev_clear_flag(hdev, HCI_PA_SYNC); @@ -6403,6 +6415,8 @@ static void hci_le_adv_report_evt(struct hci_dev *hdev, void *data, info->length + 1)) break; + hci_store_wake_reason(hdev, &info->bdaddr, info->bdaddr_type); + if (info->length <= max_adv_len(hdev)) { rssi = info->data[info->length]; process_adv_report(hdev, info->type, &info->bdaddr, @@ -6491,6 +6505,8 @@ static void hci_le_ext_adv_report_evt(struct hci_dev *hdev, void *data, info->length)) break; + hci_store_wake_reason(hdev, &info->bdaddr, info->bdaddr_type); + evt_type = __le16_to_cpu(info->type) & LE_EXT_ADV_EVT_TYPE_MASK; legacy_evt_type = ext_evt_type_to_legacy(hdev, evt_type); @@ -6536,6 +6552,7 @@ static void hci_le_pa_sync_established_evt(struct hci_dev *hdev, void *data, bt_dev_dbg(hdev, "status 0x%2.2x", ev->status); hci_dev_lock(hdev); + hci_store_wake_reason(hdev, &ev->bdaddr, ev->bdaddr_type); hci_dev_clear_flag(hdev, HCI_PA_SYNC); @@ -6834,6 +6851,8 @@ static void hci_le_direct_adv_report_evt(struct hci_dev *hdev, void *data, for (i = 0; i < ev->num; i++) { struct hci_ev_le_direct_adv_info *info = &ev->info[i]; + hci_store_wake_reason(hdev, &info->bdaddr, info->bdaddr_type); + process_adv_report(hdev, info->type, &info->bdaddr, info->bdaddr_type, &info->direct_addr, info->direct_addr_type, HCI_ADV_PHY_1M, 0, @@ -7517,73 +7536,29 @@ static bool hci_get_cmd_complete(struct hci_dev *hdev, u16 opcode, return true; } -static void hci_store_wake_reason(struct hci_dev *hdev, u8 event, - struct sk_buff *skb) +static void hci_store_wake_reason(struct hci_dev *hdev, + const bdaddr_t *bdaddr, u8 addr_type) + __must_hold(&hdev->lock) { - struct hci_ev_le_advertising_info *adv; - struct hci_ev_le_direct_adv_info *direct_adv; - struct hci_ev_le_ext_adv_info *ext_adv; - const struct hci_ev_conn_complete *conn_complete = (void *)skb->data; - const struct hci_ev_conn_request *conn_request = (void *)skb->data; - - hci_dev_lock(hdev); + lockdep_assert_held(&hdev->lock); /* If we are currently suspended and this is the first BT event seen, * save the wake reason associated with the event. */ if (!hdev->suspended || hdev->wake_reason) - goto unlock; + return; + + if (!bdaddr) { + hdev->wake_reason = MGMT_WAKE_REASON_UNEXPECTED; + return; + } /* Default to remote wake. Values for wake_reason are documented in the * Bluez mgmt api docs. */ hdev->wake_reason = MGMT_WAKE_REASON_REMOTE_WAKE; - - /* Once configured for remote wakeup, we should only wake up for - * reconnections. It's useful to see which device is waking us up so - * keep track of the bdaddr of the connection event that woke us up. - */ - if (event == HCI_EV_CONN_REQUEST) { - bacpy(&hdev->wake_addr, &conn_request->bdaddr); - hdev->wake_addr_type = BDADDR_BREDR; - } else if (event == HCI_EV_CONN_COMPLETE) { - bacpy(&hdev->wake_addr, &conn_complete->bdaddr); - hdev->wake_addr_type = BDADDR_BREDR; - } else if (event == HCI_EV_LE_META) { - struct hci_ev_le_meta *le_ev = (void *)skb->data; - u8 subevent = le_ev->subevent; - u8 *ptr = &skb->data[sizeof(*le_ev)]; - u8 num_reports = *ptr; - - if ((subevent == HCI_EV_LE_ADVERTISING_REPORT || - subevent == HCI_EV_LE_DIRECT_ADV_REPORT || - subevent == HCI_EV_LE_EXT_ADV_REPORT) && - num_reports) { - adv = (void *)(ptr + 1); - direct_adv = (void *)(ptr + 1); - ext_adv = (void *)(ptr + 1); - - switch (subevent) { - case HCI_EV_LE_ADVERTISING_REPORT: - bacpy(&hdev->wake_addr, &adv->bdaddr); - hdev->wake_addr_type = adv->bdaddr_type; - break; - case HCI_EV_LE_DIRECT_ADV_REPORT: - bacpy(&hdev->wake_addr, &direct_adv->bdaddr); - hdev->wake_addr_type = direct_adv->bdaddr_type; - break; - case HCI_EV_LE_EXT_ADV_REPORT: - bacpy(&hdev->wake_addr, &ext_adv->bdaddr); - hdev->wake_addr_type = ext_adv->bdaddr_type; - break; - } - } - } else { - hdev->wake_reason = MGMT_WAKE_REASON_UNEXPECTED; - } - -unlock: - hci_dev_unlock(hdev); + bacpy(&hdev->wake_addr, bdaddr); + hdev->wake_addr_type = addr_type; } #define HCI_EV_VL(_op, _func, _min_len, _max_len) \ @@ -7830,14 +7805,15 @@ void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb) skb_pull(skb, HCI_EVENT_HDR_SIZE); - /* Store wake reason if we're suspended */ - hci_store_wake_reason(hdev, event, skb); - bt_dev_dbg(hdev, "event 0x%2.2x", event); hci_event_func(hdev, event, skb, &opcode, &status, &req_complete, &req_complete_skb); + hci_dev_lock(hdev); + hci_store_wake_reason(hdev, NULL, 0); + hci_dev_unlock(hdev); + if (req_complete) { req_complete(hdev, status, opcode); } else if (req_complete_skb) { From 2969554bcfccb5c609f6b6cd4a014933f3a66dd0 Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Wed, 25 Mar 2026 21:07:43 +0200 Subject: [PATCH 04/14] Bluetooth: hci_sync: hci_cmd_sync_queue_once() return -EEXIST if exists hci_cmd_sync_queue_once() needs to indicate whether a queue item was added, so caller can know if callbacks are called, so it can avoid leaking resources. Change the function to return -EEXIST if queue item already exists. Modify all callsites to handle that. Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_sync.c | 53 +++++++++++++++++++++++++++------------- 1 file changed, 36 insertions(+), 17 deletions(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 6283a4df78b0..97745710e3ce 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -780,7 +780,7 @@ int hci_cmd_sync_queue_once(struct hci_dev *hdev, hci_cmd_sync_work_func_t func, void *data, hci_cmd_sync_work_destroy_t destroy) { if (hci_cmd_sync_lookup_entry(hdev, func, data, destroy)) - return 0; + return -EEXIST; return hci_cmd_sync_queue(hdev, func, data, destroy); } @@ -3262,6 +3262,8 @@ static int update_passive_scan_sync(struct hci_dev *hdev, void *data) int hci_update_passive_scan(struct hci_dev *hdev) { + int err; + /* Only queue if it would have any effect */ if (!test_bit(HCI_UP, &hdev->flags) || test_bit(HCI_INIT, &hdev->flags) || @@ -3271,8 +3273,9 @@ int hci_update_passive_scan(struct hci_dev *hdev) hci_dev_test_flag(hdev, HCI_UNREGISTER)) return 0; - return hci_cmd_sync_queue_once(hdev, update_passive_scan_sync, NULL, - NULL); + err = hci_cmd_sync_queue_once(hdev, update_passive_scan_sync, NULL, + NULL); + return (err == -EEXIST) ? 0 : err; } int hci_write_sc_support_sync(struct hci_dev *hdev, u8 val) @@ -6965,8 +6968,11 @@ static int hci_acl_create_conn_sync(struct hci_dev *hdev, void *data) int hci_connect_acl_sync(struct hci_dev *hdev, struct hci_conn *conn) { - return hci_cmd_sync_queue_once(hdev, hci_acl_create_conn_sync, conn, - NULL); + int err; + + err = hci_cmd_sync_queue_once(hdev, hci_acl_create_conn_sync, conn, + NULL); + return (err == -EEXIST) ? 0 : err; } static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err) @@ -7002,8 +7008,11 @@ static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err) int hci_connect_le_sync(struct hci_dev *hdev, struct hci_conn *conn) { - return hci_cmd_sync_queue_once(hdev, hci_le_create_conn_sync, conn, - create_le_conn_complete); + int err; + + err = hci_cmd_sync_queue_once(hdev, hci_le_create_conn_sync, conn, + create_le_conn_complete); + return (err == -EEXIST) ? 0 : err; } int hci_cancel_connect_sync(struct hci_dev *hdev, struct hci_conn *conn) @@ -7210,8 +7219,11 @@ static int hci_le_pa_create_sync(struct hci_dev *hdev, void *data) int hci_connect_pa_sync(struct hci_dev *hdev, struct hci_conn *conn) { - return hci_cmd_sync_queue_once(hdev, hci_le_pa_create_sync, conn, - create_pa_complete); + int err; + + err = hci_cmd_sync_queue_once(hdev, hci_le_pa_create_sync, conn, + create_pa_complete); + return (err == -EEXIST) ? 0 : err; } static void create_big_complete(struct hci_dev *hdev, void *data, int err) @@ -7273,8 +7285,11 @@ static int hci_le_big_create_sync(struct hci_dev *hdev, void *data) int hci_connect_big_sync(struct hci_dev *hdev, struct hci_conn *conn) { - return hci_cmd_sync_queue_once(hdev, hci_le_big_create_sync, conn, - create_big_complete); + int err; + + err = hci_cmd_sync_queue_once(hdev, hci_le_big_create_sync, conn, + create_big_complete); + return (err == -EEXIST) ? 0 : err; } struct past_data { @@ -7366,7 +7381,7 @@ int hci_past_sync(struct hci_conn *conn, struct hci_conn *le) if (err) kfree(data); - return err; + return (err == -EEXIST) ? 0 : err; } static void le_read_features_complete(struct hci_dev *hdev, void *data, int err) @@ -7453,7 +7468,7 @@ int hci_le_read_remote_features(struct hci_conn *conn) else err = -EOPNOTSUPP; - return err; + return (err == -EEXIST) ? 0 : err; } static void pkt_type_changed(struct hci_dev *hdev, void *data, int err) @@ -7479,6 +7494,7 @@ int hci_acl_change_pkt_type(struct hci_conn *conn, u16 pkt_type) { struct hci_dev *hdev = conn->hdev; struct hci_cp_change_conn_ptype *cp; + int err; cp = kmalloc_obj(*cp); if (!cp) @@ -7487,8 +7503,9 @@ int hci_acl_change_pkt_type(struct hci_conn *conn, u16 pkt_type) cp->handle = cpu_to_le16(conn->handle); cp->pkt_type = cpu_to_le16(pkt_type); - return hci_cmd_sync_queue_once(hdev, hci_change_conn_ptype_sync, cp, - pkt_type_changed); + err = hci_cmd_sync_queue_once(hdev, hci_change_conn_ptype_sync, cp, + pkt_type_changed); + return (err == -EEXIST) ? 0 : err; } static void le_phy_update_complete(struct hci_dev *hdev, void *data, int err) @@ -7514,6 +7531,7 @@ int hci_le_set_phy(struct hci_conn *conn, u8 tx_phys, u8 rx_phys) { struct hci_dev *hdev = conn->hdev; struct hci_cp_le_set_phy *cp; + int err; cp = kmalloc_obj(*cp); if (!cp) @@ -7524,6 +7542,7 @@ int hci_le_set_phy(struct hci_conn *conn, u8 tx_phys, u8 rx_phys) cp->tx_phys = tx_phys; cp->rx_phys = rx_phys; - return hci_cmd_sync_queue_once(hdev, hci_le_set_phy_sync, cp, - le_phy_update_complete); + err = hci_cmd_sync_queue_once(hdev, hci_le_set_phy_sync, cp, + le_phy_update_complete); + return (err == -EEXIST) ? 0 : err; } From aca377208e7f7322bf4e107cdec6e7d7e8aa7a88 Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Wed, 25 Mar 2026 21:07:44 +0200 Subject: [PATCH 05/14] Bluetooth: hci_sync: fix leaks when hci_cmd_sync_queue_once fails When hci_cmd_sync_queue_once() returns with error, the destroy callback will not be called. Fix leaking references / memory on these failures. Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_sync.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 97745710e3ce..8cbbba50e77e 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -7460,13 +7460,16 @@ int hci_le_read_remote_features(struct hci_conn *conn) * role is possible. Otherwise just transition into the * connected state without requesting the remote features. */ - if (conn->out || (hdev->le_features[0] & HCI_LE_PERIPHERAL_FEATURES)) + if (conn->out || (hdev->le_features[0] & HCI_LE_PERIPHERAL_FEATURES)) { err = hci_cmd_sync_queue_once(hdev, hci_le_read_remote_features_sync, hci_conn_hold(conn), le_read_features_complete); - else + if (err) + hci_conn_drop(conn); + } else { err = -EOPNOTSUPP; + } return (err == -EEXIST) ? 0 : err; } @@ -7505,6 +7508,9 @@ int hci_acl_change_pkt_type(struct hci_conn *conn, u16 pkt_type) err = hci_cmd_sync_queue_once(hdev, hci_change_conn_ptype_sync, cp, pkt_type_changed); + if (err) + kfree(cp); + return (err == -EEXIST) ? 0 : err; } @@ -7544,5 +7550,8 @@ int hci_le_set_phy(struct hci_conn *conn, u8 tx_phys, u8 rx_phys) err = hci_cmd_sync_queue_once(hdev, hci_le_set_phy_sync, cp, le_phy_update_complete); + if (err) + kfree(cp); + return (err == -EEXIST) ? 0 : err; } From 035c25007c9e698bef3826070ee34bb6d778020c Mon Sep 17 00:00:00 2001 From: Luiz Augusto von Dentz Date: Wed, 25 Mar 2026 11:11:46 -0400 Subject: [PATCH 06/14] Bluetooth: hci_sync: Fix UAF in le_read_features_complete This fixes the following backtrace caused by hci_conn being freed before le_read_features_complete but after hci_le_read_remote_features_sync so hci_conn_del -> hci_cmd_sync_dequeue is not able to prevent it: ================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline] BUG: KASAN: slab-use-after-free in hci_conn_drop include/net/bluetooth/hci_core.h:1688 [inline] BUG: KASAN: slab-use-after-free in le_read_features_complete+0x5b/0x340 net/bluetooth/hci_sync.c:7344 Write of size 4 at addr ffff8880796b0010 by task kworker/u9:0/52 CPU: 0 UID: 0 PID: 52 Comm: kworker/u9:0 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: hci0 hci_cmd_sync_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xcd/0x630 mm/kasan/report.c:482 kasan_report+0xe0/0x110 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:194 [inline] kasan_check_range+0x100/0x1b0 mm/kasan/generic.c:200 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline] hci_conn_drop include/net/bluetooth/hci_core.h:1688 [inline] le_read_features_complete+0x5b/0x340 net/bluetooth/hci_sync.c:7344 hci_cmd_sync_work+0x1ff/0x430 net/bluetooth/hci_sync.c:334 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 5932: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] __hci_conn_add+0xf8/0x1c70 net/bluetooth/hci_conn.c:963 hci_conn_add_unset+0x76/0x100 net/bluetooth/hci_conn.c:1084 le_conn_complete_evt+0x639/0x1f20 net/bluetooth/hci_event.c:5714 hci_le_enh_conn_complete_evt+0x23d/0x380 net/bluetooth/hci_event.c:5861 hci_le_meta_evt+0x357/0x5e0 net/bluetooth/hci_event.c:7408 hci_event_func net/bluetooth/hci_event.c:7716 [inline] hci_event_packet+0x685/0x11c0 net/bluetooth/hci_event.c:7773 hci_rx_work+0x2c9/0xeb0 net/bluetooth/hci_core.c:4076 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Freed by task 5932: kasan_save_stack+0x33/0x60 mm/kasan/common.c:56 kasan_save_track+0x14/0x30 mm/kasan/common.c:77 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kfree+0x2f8/0x6e0 mm/slub.c:6871 device_release+0xa4/0x240 drivers/base/core.c:2565 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1e7/0x590 lib/kobject.c:737 put_device drivers/base/core.c:3797 [inline] device_unregister+0x2f/0xc0 drivers/base/core.c:3920 hci_conn_del_sysfs+0xb4/0x180 net/bluetooth/hci_sysfs.c:79 hci_conn_cleanup net/bluetooth/hci_conn.c:173 [inline] hci_conn_del+0x657/0x1180 net/bluetooth/hci_conn.c:1234 hci_disconn_complete_evt+0x410/0xa00 net/bluetooth/hci_event.c:3451 hci_event_func net/bluetooth/hci_event.c:7719 [inline] hci_event_packet+0xa10/0x11c0 net/bluetooth/hci_event.c:7773 hci_rx_work+0x2c9/0xeb0 net/bluetooth/hci_core.c:4076 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3421 kthread+0x3c5/0x780 kernel/kthread.c:463 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 The buggy address belongs to the object at ffff8880796b0000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 16 bytes inside of freed 8192-byte region [ffff8880796b0000, ffff8880796b2000) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x796b0 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813ff27280 0000000000000000 0000000000000001 raw: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813ff27280 0000000000000000 0000000000000001 head: 0000000000000000 0000000000020002 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001e5ac01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5657, tgid 5657 (dhcpcd-run-hook), ts 79819636908, free_ts 79814310558 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845 prep_new_page mm/page_alloc.c:1853 [inline] get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5183 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c3/0x430 mm/slub.c:3302 ___slab_alloc+0xe18/0x1c90 mm/slub.c:4651 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] __kmalloc_cache_noprof+0x477/0x800 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0xc8a/0x2140 security/tomoyo/audit.c:264 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0xec1/0x20b0 security/tomoyo/domain.c:888 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline] tomoyo_bprm_check_security+0x12d/0x1d0 security/tomoyo/tomoyo.c:92 security_bprm_check+0x1b9/0x1e0 security/security.c:794 search_binary_handler fs/exec.c:1659 [inline] exec_binprm fs/exec.c:1701 [inline] bprm_execve fs/exec.c:1753 [inline] bprm_execve+0x81e/0x1620 fs/exec.c:1729 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1859 page last free pid 5657 tgid 5657 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901 discard_slab mm/slub.c:3346 [inline] __put_partials+0x130/0x170 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x4c/0xf0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] __kmalloc_cache_noprof+0x274/0x800 mm/slub.c:5766 kmalloc_noprof include/linux/slab.h:957 [inline] tomoyo_print_header security/tomoyo/audit.c:156 [inline] tomoyo_init_log+0x197/0x2140 security/tomoyo/audit.c:255 tomoyo_supervisor+0x302/0x13b0 security/tomoyo/common.c:2198 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x191/0x200 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0xec1/0x20b0 security/tomoyo/domain.c:888 tomoyo_bprm_check_security security/tomoyo/tomoyo.c:102 [inline] tomoyo_bprm_check_security+0x12d/0x1d0 security/tomoyo/tomoyo.c:92 security_bprm_check+0x1b9/0x1e0 security/security.c:794 search_binary_handler fs/exec.c:1659 [inline] exec_binprm fs/exec.c:1701 [inline] bprm_execve fs/exec.c:1753 [inline] bprm_execve+0x81e/0x1620 fs/exec.c:1729 do_execveat_common.isra.0+0x4a5/0x610 fs/exec.c:1859 do_execve fs/exec.c:1933 [inline] __do_sys_execve fs/exec.c:2009 [inline] __se_sys_execve fs/exec.c:2004 [inline] __x64_sys_execve+0x8e/0xb0 fs/exec.c:2004 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff8880796aff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880796aff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880796b0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880796b0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880796b0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Fixes: a106e50be74b ("Bluetooth: HCI: Add support for LL Extended Feature Set") Reported-by: syzbot+87badbb9094e008e0685@syzkaller.appspotmail.com Tested-by: syzbot+87badbb9094e008e0685@syzkaller.appspotmail.com Closes: https://syzbot.org/bug?extid=87badbb9094e008e0685 Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Pauli Virtanen --- net/bluetooth/hci_sync.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index 8cbbba50e77e..ffb0ceda6f7b 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -7390,10 +7390,8 @@ static void le_read_features_complete(struct hci_dev *hdev, void *data, int err) bt_dev_dbg(hdev, "err %d", err); - if (err == -ECANCELED) - return; - hci_conn_drop(conn); + hci_conn_put(conn); } static int hci_le_read_all_remote_features_sync(struct hci_dev *hdev, @@ -7463,10 +7461,12 @@ int hci_le_read_remote_features(struct hci_conn *conn) if (conn->out || (hdev->le_features[0] & HCI_LE_PERIPHERAL_FEATURES)) { err = hci_cmd_sync_queue_once(hdev, hci_le_read_remote_features_sync, - hci_conn_hold(conn), + hci_conn_hold(hci_conn_get(conn)), le_read_features_complete); - if (err) + if (err) { hci_conn_drop(conn); + hci_conn_put(conn); + } } else { err = -EOPNOTSUPP; } From 0ffac654e95c1bdfe2d4edf28fb18d6ba1f103e6 Mon Sep 17 00:00:00 2001 From: Jonathan Rissanen Date: Fri, 27 Mar 2026 11:47:21 +0100 Subject: [PATCH 07/14] Bluetooth: hci_h4: Fix race during initialization Commit 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") fixed a race for hci commands sent during initialization. However, there is still a race that happens if an hci event from one of these commands is received before HCI_UART_REGISTERED has been set at the end of hci_uart_register_dev(). The event will be ignored which causes the command to fail with a timeout in the log: "Bluetooth: hci0: command 0x1003 tx timeout" This is because the hci event receive path (hci_uart_tty_receive -> h4_recv) requires HCI_UART_REGISTERED to be set in h4_recv(), while the hci command transmit path (hci_uart_send_frame -> h4_enqueue) only requires HCI_UART_PROTO_INIT to be set in hci_uart_send_frame(). The check for HCI_UART_REGISTERED was originally added in commit c2578202919a ("Bluetooth: Fix H4 crash from incoming UART packets") to fix a crash caused by hu->hdev being null dereferenced. That can no longer happen: once HCI_UART_PROTO_INIT is set in hci_uart_register_dev() all pointers (hu, hu->priv and hu->hdev) are valid, and hci_uart_tty_receive() already calls h4_recv() on HCI_UART_PROTO_INIT or HCI_UART_PROTO_READY. Remove the check for HCI_UART_REGISTERED in h4_recv() to fix the race condition. Fixes: 5df5dafc171b ("Bluetooth: hci_uart: Fix another race during initialization") Signed-off-by: Jonathan Rissanen Signed-off-by: Luiz Augusto von Dentz --- drivers/bluetooth/hci_h4.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/bluetooth/hci_h4.c b/drivers/bluetooth/hci_h4.c index 07cc2a79a77b..a889a66a326f 100644 --- a/drivers/bluetooth/hci_h4.c +++ b/drivers/bluetooth/hci_h4.c @@ -109,9 +109,6 @@ static int h4_recv(struct hci_uart *hu, const void *data, int count) { struct h4_struct *h4 = hu->priv; - if (!test_bit(HCI_UART_REGISTERED, &hu->flags)) - return -EUNATCH; - h4->rx_skb = h4_recv_buf(hu, h4->rx_skb, data, count, h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts)); if (IS_ERR(h4->rx_skb)) { From b8dbe9648d69059cfe3a28917bfbf7e61efd7f15 Mon Sep 17 00:00:00 2001 From: Keenan Dong Date: Sat, 28 Mar 2026 16:46:47 +0800 Subject: [PATCH 08/14] Bluetooth: MGMT: validate LTK enc_size on load Load Long Term Keys stores the user-provided enc_size and later uses it to size fixed-size stack operations when replying to LE LTK requests. An enc_size larger than the 16-byte key buffer can therefore overflow the reply stack buffer. Reject oversized enc_size values while validating the management LTK record so invalid keys never reach the stored key state. Fixes: 346af67b8d11 ("Bluetooth: Add MGMT handlers for dealing with SMP LTK's") Reported-by: Keenan Dong Signed-off-by: Keenan Dong Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/mgmt.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index e5f9287fb826..adcd86c15b4e 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -7248,6 +7248,9 @@ static bool ltk_is_valid(struct mgmt_ltk_info *key) if (key->initiator != 0x00 && key->initiator != 0x01) return false; + if (key->enc_size > sizeof(key->val)) + return false; + switch (key->addr.type) { case BDADDR_LE_PUBLIC: return true; From a2639a7f0f5bf7d73f337f8f077c19415c62ed2c Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Sun, 29 Mar 2026 16:43:01 +0300 Subject: [PATCH 09/14] Bluetooth: hci_conn: fix potential UAF in set_cig_params_sync hci_conn lookup and field access must be covered by hdev lock in set_cig_params_sync, otherwise it's possible it is freed concurrently. Take hdev lock to prevent hci_conn from being deleted or modified concurrently. Just RCU lock is not suitable here, as we also want to avoid "tearing" in the configuration. Fixes: a091289218202 ("Bluetooth: hci_conn: Fix hci_le_set_cig_params") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_conn.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c index e6393f17576b..11d3ad8d2551 100644 --- a/net/bluetooth/hci_conn.c +++ b/net/bluetooth/hci_conn.c @@ -1843,9 +1843,13 @@ static int set_cig_params_sync(struct hci_dev *hdev, void *data) u8 aux_num_cis = 0; u8 cis_id; + hci_dev_lock(hdev); + conn = hci_conn_hash_lookup_cig(hdev, cig_id); - if (!conn) + if (!conn) { + hci_dev_unlock(hdev); return 0; + } qos = &conn->iso_qos; pdu->cig_id = cig_id; @@ -1884,6 +1888,8 @@ static int set_cig_params_sync(struct hci_dev *hdev, void *data) } pdu->num_cis = aux_num_cis; + hci_dev_unlock(hdev); + if (!pdu->num_cis) return 0; From b255531b27da336571411248c2a72a350662bd09 Mon Sep 17 00:00:00 2001 From: Pauli Virtanen Date: Sun, 29 Mar 2026 16:43:02 +0300 Subject: [PATCH 10/14] Bluetooth: hci_event: fix potential UAF in hci_le_remote_conn_param_req_evt hci_conn lookup and field access must be covered by hdev lock in hci_le_remote_conn_param_req_evt, otherwise it's possible it is freed concurrently. Extend the hci_dev_lock critical section to cover all conn usage. Fixes: 95118dd4edfec ("Bluetooth: hci_event: Use of a function table to handle LE subevents") Signed-off-by: Pauli Virtanen Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_event.c | 33 ++++++++++++++++++++------------- 1 file changed, 20 insertions(+), 13 deletions(-) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 81d2f9a3eec9..3ebc5e6d45d9 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -6784,25 +6784,31 @@ static void hci_le_remote_conn_param_req_evt(struct hci_dev *hdev, void *data, latency = le16_to_cpu(ev->latency); timeout = le16_to_cpu(ev->timeout); + hci_dev_lock(hdev); + hcon = hci_conn_hash_lookup_handle(hdev, handle); - if (!hcon || hcon->state != BT_CONNECTED) - return send_conn_param_neg_reply(hdev, handle, - HCI_ERROR_UNKNOWN_CONN_ID); + if (!hcon || hcon->state != BT_CONNECTED) { + send_conn_param_neg_reply(hdev, handle, + HCI_ERROR_UNKNOWN_CONN_ID); + goto unlock; + } - if (max > hcon->le_conn_max_interval) - return send_conn_param_neg_reply(hdev, handle, - HCI_ERROR_INVALID_LL_PARAMS); + if (max > hcon->le_conn_max_interval) { + send_conn_param_neg_reply(hdev, handle, + HCI_ERROR_INVALID_LL_PARAMS); + goto unlock; + } - if (hci_check_conn_params(min, max, latency, timeout)) - return send_conn_param_neg_reply(hdev, handle, - HCI_ERROR_INVALID_LL_PARAMS); + if (hci_check_conn_params(min, max, latency, timeout)) { + send_conn_param_neg_reply(hdev, handle, + HCI_ERROR_INVALID_LL_PARAMS); + goto unlock; + } if (hcon->role == HCI_ROLE_MASTER) { struct hci_conn_params *params; u8 store_hint; - hci_dev_lock(hdev); - params = hci_conn_params_lookup(hdev, &hcon->dst, hcon->dst_type); if (params) { @@ -6815,8 +6821,6 @@ static void hci_le_remote_conn_param_req_evt(struct hci_dev *hdev, void *data, store_hint = 0x00; } - hci_dev_unlock(hdev); - mgmt_new_conn_param(hdev, &hcon->dst, hcon->dst_type, store_hint, min, max, latency, timeout); } @@ -6830,6 +6834,9 @@ static void hci_le_remote_conn_param_req_evt(struct hci_dev *hdev, void *data, cp.max_ce_len = 0; hci_send_cmd(hdev, HCI_OP_LE_CONN_PARAM_REQ_REPLY, sizeof(cp), &cp); + +unlock: + hci_dev_unlock(hdev); } static void hci_le_direct_adv_report_evt(struct hci_dev *hdev, void *data, From bda93eec78cdbfe5cda00785cefebd443e56b88b Mon Sep 17 00:00:00 2001 From: Keenan Dong Date: Wed, 1 Apr 2026 22:25:26 +0800 Subject: [PATCH 11/14] Bluetooth: MGMT: validate mesh send advertising payload length mesh_send() currently bounds MGMT_OP_MESH_SEND by total command length, but it never verifies that the bytes supplied for the flexible adv_data[] array actually match the embedded adv_data_len field. MGMT_MESH_SEND_SIZE only covers the fixed header, so a truncated command can still pass the existing 20..50 byte range check and later drive the async mesh send path past the end of the queued command buffer. Keep rejecting zero-length and oversized advertising payloads, but validate adv_data_len explicitly and require the command length to exactly match the flexible array size before queueing the request. Fixes: b338d91703fa ("Bluetooth: Implement support for Mesh") Reported-by: Keenan Dong Signed-off-by: Keenan Dong Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/mgmt.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c index adcd86c15b4e..b05bb380e5f8 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -2478,6 +2478,7 @@ static int mesh_send(struct sock *sk, struct hci_dev *hdev, void *data, u16 len) struct mgmt_mesh_tx *mesh_tx; struct mgmt_cp_mesh_send *send = data; struct mgmt_rp_mesh_read_features rp; + u16 expected_len; bool sending; int err = 0; @@ -2485,12 +2486,19 @@ static int mesh_send(struct sock *sk, struct hci_dev *hdev, void *data, u16 len) !hci_dev_test_flag(hdev, HCI_MESH_EXPERIMENTAL)) return mgmt_cmd_status(sk, hdev->id, MGMT_OP_MESH_SEND, MGMT_STATUS_NOT_SUPPORTED); - if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED) || - len <= MGMT_MESH_SEND_SIZE || - len > (MGMT_MESH_SEND_SIZE + 31)) + if (!hci_dev_test_flag(hdev, HCI_LE_ENABLED)) return mgmt_cmd_status(sk, hdev->id, MGMT_OP_MESH_SEND, MGMT_STATUS_REJECTED); + if (!send->adv_data_len || send->adv_data_len > 31) + return mgmt_cmd_status(sk, hdev->id, MGMT_OP_MESH_SEND, + MGMT_STATUS_REJECTED); + + expected_len = struct_size(send, adv_data, send->adv_data_len); + if (expected_len != len) + return mgmt_cmd_status(sk, hdev->id, MGMT_OP_MESH_SEND, + MGMT_STATUS_INVALID_PARAMS); + hci_dev_lock(hdev); memset(&rp, 0, sizeof(rp)); From d05111bfe37bfd8bd4d2dfe6675d6bdeef43f7c7 Mon Sep 17 00:00:00 2001 From: Oleh Konko Date: Tue, 31 Mar 2026 11:52:12 +0000 Subject: [PATCH 12/14] Bluetooth: SMP: force responder MITM requirements before building the pairing response smp_cmd_pairing_req() currently builds the pairing response from the initiator auth_req before enforcing the local BT_SECURITY_HIGH requirement. If the initiator omits SMP_AUTH_MITM, the response can also omit it even though the local side still requires MITM. tk_request() then sees an auth value without SMP_AUTH_MITM and may select JUST_CFM, making method selection inconsistent with the pairing policy the responder already enforces. When the local side requires HIGH security, first verify that MITM can be achieved from the IO capabilities and then force SMP_AUTH_MITM in the response in both rsp.auth_req and auth. This keeps the responder auth bits and later method selection aligned. Fixes: 2b64d153a0cc ("Bluetooth: Add MITM mechanism to LE-SMP") Cc: stable@vger.kernel.org Suggested-by: Luiz Augusto von Dentz Signed-off-by: Oleh Konko Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/smp.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index 485e3468bd26..deb8dd244b77 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -1826,7 +1826,7 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) if (sec_level > conn->hcon->pending_sec_level) conn->hcon->pending_sec_level = sec_level; - /* If we need MITM check that it can be achieved */ + /* If we need MITM check that it can be achieved. */ if (conn->hcon->pending_sec_level >= BT_SECURITY_HIGH) { u8 method; @@ -1834,6 +1834,10 @@ static u8 smp_cmd_pairing_req(struct l2cap_conn *conn, struct sk_buff *skb) req->io_capability); if (method == JUST_WORKS || method == JUST_CFM) return SMP_AUTH_REQUIREMENTS; + + /* Force MITM bit if it isn't set by the initiator. */ + auth |= SMP_AUTH_MITM; + rsp.auth_req |= SMP_AUTH_MITM; } key_size = min(req->max_key_size, rsp.max_key_size); From 20756fec2f0108cb88e815941f1ffff88dc286fe Mon Sep 17 00:00:00 2001 From: Oleh Konko Date: Tue, 31 Mar 2026 11:52:13 +0000 Subject: [PATCH 13/14] Bluetooth: SMP: derive legacy responder STK authentication from MITM state The legacy responder path in smp_random() currently labels the stored STK as authenticated whenever pending_sec_level is BT_SECURITY_HIGH. That reflects what the local service requested, not what the pairing flow actually achieved. For Just Works/Confirm legacy pairing, SMP_FLAG_MITM_AUTH stays clear and the resulting STK should remain unauthenticated even if the local side requested HIGH security. Use the established MITM state when storing the responder STK so the key metadata matches the pairing result. This also keeps the legacy path aligned with the Secure Connections code, which already treats JUST_WORKS/JUST_CFM as unauthenticated. Fixes: fff3490f4781 ("Bluetooth: Fix setting correct authentication information for SMP STK") Cc: stable@vger.kernel.org Signed-off-by: Oleh Konko Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/smp.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c index deb8dd244b77..98f1da4f5f55 100644 --- a/net/bluetooth/smp.c +++ b/net/bluetooth/smp.c @@ -1018,10 +1018,7 @@ static u8 smp_random(struct smp_chan *smp) smp_s1(smp->tk, smp->prnd, smp->rrnd, stk); - if (hcon->pending_sec_level == BT_SECURITY_HIGH) - auth = 1; - else - auth = 0; + auth = test_bit(SMP_FLAG_MITM_AUTH, &smp->flags) ? 1 : 0; /* Even though there's no _RESPONDER suffix this is the * responder STK we're adding for later lookup (the initiator From bc39a094730ce062fa034a529c93147c096cb488 Mon Sep 17 00:00:00 2001 From: hkbinbin Date: Tue, 31 Mar 2026 05:39:16 +0000 Subject: [PATCH 14/14] Bluetooth: hci_sync: fix stack buffer overflow in hci_le_big_create_sync MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit hci_le_big_create_sync() uses DEFINE_FLEX to allocate a struct hci_cp_le_big_create_sync on the stack with room for 0x11 (17) BIS entries. However, conn->num_bis can hold up to HCI_MAX_ISO_BIS (31) entries — validated against ISO_MAX_NUM_BIS (0x1f) in the caller hci_conn_big_create_sync(). When conn->num_bis is between 18 and 31, the memcpy that copies conn->bis into cp->bis writes up to 14 bytes past the stack buffer, corrupting adjacent stack memory. This is trivially reproducible: binding an ISO socket with bc_num_bis = ISO_MAX_NUM_BIS (31) and calling listen() will eventually trigger hci_le_big_create_sync() from the HCI command sync worker, causing a KASAN-detectable stack-out-of-bounds write: BUG: KASAN: stack-out-of-bounds in hci_le_big_create_sync+0x256/0x3b0 Write of size 31 at addr ffffc90000487b48 by task kworker/u9:0/71 Fix this by changing the DEFINE_FLEX count from the incorrect 0x11 to HCI_MAX_ISO_BIS, which matches the maximum number of BIS entries that conn->bis can actually carry. Fixes: 42ecf1947135 ("Bluetooth: ISO: Do not emit LE BIG Create Sync if previous is pending") Cc: stable@vger.kernel.org Signed-off-by: hkbinbin Reviewed-by: Paul Menzel Signed-off-by: Luiz Augusto von Dentz --- net/bluetooth/hci_sync.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index ffb0ceda6f7b..919ec275dd23 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -7241,7 +7241,8 @@ static void create_big_complete(struct hci_dev *hdev, void *data, int err) static int hci_le_big_create_sync(struct hci_dev *hdev, void *data) { - DEFINE_FLEX(struct hci_cp_le_big_create_sync, cp, bis, num_bis, 0x11); + DEFINE_FLEX(struct hci_cp_le_big_create_sync, cp, bis, num_bis, + HCI_MAX_ISO_BIS); struct hci_conn *conn = data; struct bt_iso_qos *qos = &conn->iso_qos; int err;