From: Zhengping Jiang <jiangzp@xxxxxxxxxx>
[ Upstream commit 1857c19941c87eb36ad47f22a406be5dfe5eff9f ]
When the HCI_UNREGISTER flag is set, no jobs should be scheduled. Fix
potential race when HCI_UNREGISTER is set after the flag is tested in
hci_cmd_sync_queue.
Fixes: 0b94f2651f56 ("Bluetooth: hci_sync: Fix queuing commands when HCI_UNREGISTER is set")
Signed-off-by: Zhengping Jiang <jiangzp@xxxxxxxxxx>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/net/bluetooth/hci_core.h | 1 +
net/bluetooth/hci_core.c | 2 ++
net/bluetooth/hci_sync.c | 20 ++++++++++++++------
3 files changed, 17 insertions(+), 6 deletions(-)
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 061fec6fd0152..84c5ce57eab69 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -513,6 +513,7 @@ struct hci_dev {
struct work_struct cmd_sync_work;
struct list_head cmd_sync_work_list;
struct mutex cmd_sync_work_lock;
+ struct mutex unregister_lock;
struct work_struct cmd_sync_cancel_work;
struct work_struct reenable_adv_work;
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 334e308451f53..ac36e7ae70b21 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2685,7 +2685,9 @@ void hci_unregister_dev(struct hci_dev *hdev)
{
BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus);
+ mutex_lock(&hdev->unregister_lock);
hci_dev_set_flag(hdev, HCI_UNREGISTER);
+ mutex_unlock(&hdev->unregister_lock);
write_lock(&hci_dev_list_lock);
list_del(&hdev->list);
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index e8b78104a4071..40a6cfa2f9a07 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -629,6 +629,7 @@ void hci_cmd_sync_init(struct hci_dev *hdev)
INIT_WORK(&hdev->cmd_sync_work, hci_cmd_sync_work);
INIT_LIST_HEAD(&hdev->cmd_sync_work_list);
mutex_init(&hdev->cmd_sync_work_lock);
+ mutex_init(&hdev->unregister_lock);
INIT_WORK(&hdev->cmd_sync_cancel_work, hci_cmd_sync_cancel_work);
INIT_WORK(&hdev->reenable_adv_work, reenable_adv);
@@ -688,14 +689,19 @@ int hci_cmd_sync_queue(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
void *data, hci_cmd_sync_work_destroy_t destroy)
{
struct hci_cmd_sync_work_entry *entry;
+ int err = 0;
- if (hci_dev_test_flag(hdev, HCI_UNREGISTER))
- return -ENODEV;
+ mutex_lock(&hdev->unregister_lock);
+ if (hci_dev_test_flag(hdev, HCI_UNREGISTER)) {
+ err = -ENODEV;
+ goto unlock;
+ }
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
- if (!entry)
- return -ENOMEM;
-
+ if (!entry) {
+ err = -ENOMEM;
+ goto unlock;
+ }
entry->func = func;
entry->data = data;
entry->destroy = destroy;
@@ -706,7 +712,9 @@ int hci_cmd_sync_queue(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
queue_work(hdev->req_workqueue, &hdev->cmd_sync_work);
- return 0;
+unlock:
+ mutex_unlock(&hdev->unregister_lock);
+ return err;
}
EXPORT_SYMBOL(hci_cmd_sync_queue);
--
2.39.2
