Syzbot reported a corrupted list in kobject_add_internal [1]. This happens when multiple HCI_EV_SYNC_CONN_COMPLETE event packets with status 0 are sent for the same HCI connection. This causes us to register the device more than once which corrupts the kset list. To fix this, in hci_sync_conn_complete_evt, we check whether we're trying to process the same HCI_EV_SYNC_CONN_COMPLETE event multiple times for one connection. If that's the case, the event is invalid, so we skip further processing and exit. Link: https://syzkaller.appspot.com/bug?extid=66264bf2fd0476be7e6c [1] Reported-by: syzbot+66264bf2fd0476be7e6c@xxxxxxxxxxxxxxxxxxxxxxxxx Tested-by: syzbot+66264bf2fd0476be7e6c@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Desmond Cheong Zhi Xi <desmondcheongzx@xxxxxxxxx> --- net/bluetooth/hci_event.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c index 016b2999f219..091a92338492 100644 --- a/net/bluetooth/hci_event.c +++ b/net/bluetooth/hci_event.c @@ -4373,6 +4373,8 @@ static void hci_sync_conn_complete_evt(struct hci_dev *hdev, switch (ev->status) { case 0x00: + if (conn->state == BT_CONNECTED) + goto unlock; /* Already connected, event not valid */ conn->handle = __le16_to_cpu(ev->handle); conn->state = BT_CONNECTED; conn->type = ev->link_type; -- 2.25.1
