linux-kernel - [PATCH v2] Bluetooth: hci_event: Add support for handling LE BIG Sync Lost event

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250625-handle_big_sync_lost_event-v2-1-81f163057a21@amlogic.com>
Date: Wed, 25 Jun 2025 16:42:49 +0800
From: Yang Li via B4 Relay <devnull+yang.li.amlogic.com@...nel.org>
To: Marcel Holtmann <marcel@...tmann.org>, 
 Johan Hedberg <johan.hedberg@...il.com>, 
 Luiz Augusto von Dentz <luiz.dentz@...il.com>, 
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
 Simon Horman <horms@...nel.org>
Cc: linux-bluetooth@...r.kernel.org, netdev@...r.kernel.org, 
 linux-kernel@...r.kernel.org, Yang Li <yang.li@...ogic.com>
Subject: [PATCH v2] Bluetooth: hci_event: Add support for handling LE BIG
 Sync Lost event

From: Yang Li <yang.li@...ogic.com>

When the BIS source stops, the controller sends an LE BIG Sync Lost
event (subevent 0x1E). Currently, this event is not handled, causing
the BIS stream to remain active in BlueZ and preventing recovery.

Signed-off-by: Yang Li <yang.li@...ogic.com>
---
Changes in v2:
- Matching the BIG handle is required when looking up a BIG connection.
- Use ev->reason to determine the cause of disconnection.
- Call hci_conn_del after hci_disconnect_cfm to remove the connection entry
- Delete the big connection
- Link to v1: https://lore.kernel.org/r/20250624-handle_big_sync_lost_event-v1-1-c32ce37dd6a5@amlogic.com
---
 include/net/bluetooth/hci.h |  6 ++++++
 net/bluetooth/hci_event.c   | 31 +++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 82cbd54443ac..48389a64accb 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -2849,6 +2849,12 @@ struct hci_evt_le_big_sync_estabilished {
 	__le16  bis[];
 } __packed;
 
+#define HCI_EVT_LE_BIG_SYNC_LOST 0x1e
+struct hci_evt_le_big_sync_lost {
+	__u8    handle;
+	__u8    reason;
+} __packed;
+
 #define HCI_EVT_LE_BIG_INFO_ADV_REPORT	0x22
 struct hci_evt_le_big_info_adv_report {
 	__le16  sync_handle;
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 66052d6aaa1d..d0b9c8dca891 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -7026,6 +7026,32 @@ static void hci_le_big_sync_established_evt(struct hci_dev *hdev, void *data,
 	hci_dev_unlock(hdev);
 }
 
+static void hci_le_big_sync_lost_evt(struct hci_dev *hdev, void *data,
+					    struct sk_buff *skb)
+{
+	struct hci_evt_le_big_sync_lost *ev = data;
+	struct hci_conn *bis, *conn;
+
+	bt_dev_dbg(hdev, "big handle 0x%2.2x", ev->handle);
+
+	hci_dev_lock(hdev);
+
+	list_for_each_entry(bis, &hdev->conn_hash.list, list) {
+		if (test_and_clear_bit(HCI_CONN_BIG_SYNC, &bis->flags) &&
+		    (bis->iso_qos.bcast.big == ev->handle)) {
+			hci_disconn_cfm(bis, ev->reason);
+			hci_conn_del(bis);
+
+			/* Delete the big connection */
+			conn = hci_conn_hash_lookup_pa_sync_handle(hdev, bis->sync_handle);
+			if (conn)
+				hci_conn_del(conn);
+		}
+	}
+
+	hci_dev_unlock(hdev);
+}
+
 static void hci_le_big_info_adv_report_evt(struct hci_dev *hdev, void *data,
 					   struct sk_buff *skb)
 {
@@ -7149,6 +7175,11 @@ static const struct hci_le_ev {
 		     hci_le_big_sync_established_evt,
 		     sizeof(struct hci_evt_le_big_sync_estabilished),
 		     HCI_MAX_EVENT_SIZE),
+	/* [0x1e = HCI_EVT_LE_BIG_SYNC_LOST] */
+	HCI_LE_EV_VL(HCI_EVT_LE_BIG_SYNC_LOST,
+		     hci_le_big_sync_lost_evt,
+		     sizeof(struct hci_evt_le_big_sync_lost),
+		     HCI_MAX_EVENT_SIZE),
 	/* [0x22 = HCI_EVT_LE_BIG_INFO_ADV_REPORT] */
 	HCI_LE_EV_VL(HCI_EVT_LE_BIG_INFO_ADV_REPORT,
 		     hci_le_big_info_adv_report_evt,

---
base-commit: bd35cd12d915bc410c721ba28afcada16f0ebd16
change-id: 20250612-handle_big_sync_lost_event-4c7dc64390a2

Best regards,
-- 
Yang Li <yang.li@...ogic.com>