[PATCH 6.1 199/451] Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running

Sasha Levin
2024-03-24T23:15:24Z

From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

[ Upstream commit d883a4669a1def6d121ccf5e64ad28260d1c9531 ]

This makes sure hci_cmd_sync_queue only queue new work if HCI_RUNNING
has been set otherwise there is a risk of commands being sent while
turning off.

Because hci_cmd_sync_queue can no longer queue work while HCI_RUNNING is
not set it cannot be used to power on adapters so instead
hci_cmd_sync_submit is introduced which bypass the HCI_RUNNING check, so
it behaves like the old implementation.

Link: https://lore.kernel.org/all/CAB4PzUpDMvdc8j2MdeSAy1KkAE-D3woprCwAdYWeOc-3v3c9Sw@mail.gmail.com/
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Stable-dep-of: 2615fd9a7c25 ("Bluetooth: hci_sync: Fix overwriting request callback")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
include/net/bluetooth/hci_sync.h | 2 ++
net/bluetooth/hci_sync.c | 25 +++++++++++++++++++++++--
net/bluetooth/mgmt.c | 12 ++++++++----
3 files changed, 33 insertions(+), 6 deletions(-)

diff --git a/include/net/bluetooth/hci_sync.h b/include/net/bluetooth/hci_sync.h
index 17f5a4c32f36e..2fa976c466b80 100644
--- a/include/net/bluetooth/hci_sync.h
+++ b/include/net/bluetooth/hci_sync.h
@@ -41,6 +41,8 @@ void hci_cmd_sync_clear(struct hci_dev *hdev);
void hci_cmd_sync_cancel(struct hci_dev *hdev, int err);
void __hci_cmd_sync_cancel(struct hci_dev *hdev, int err);

+int hci_cmd_sync_submit(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
+ void *data, hci_cmd_sync_work_destroy_t destroy);
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);

diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
index a337340464567..31dd064d77a42 100644
--- a/net/bluetooth/hci_sync.c
+++ b/net/bluetooth/hci_sync.c
@@ -680,8 +680,12 @@ void hci_cmd_sync_cancel(struct hci_dev *hdev, int err)
}
EXPORT_SYMBOL(hci_cmd_sync_cancel);

-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)
+/* Submit HCI command to be run in as cmd_sync_work:
+ *
+ * - hdev must _not_ be unregistered
+ */
+int hci_cmd_sync_submit(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;
@@ -711,6 +715,23 @@ int hci_cmd_sync_queue(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
mutex_unlock(&hdev->unregister_lock);
return err;
}
+EXPORT_SYMBOL(hci_cmd_sync_submit);
+
+/* Queue HCI command:
+ *
+ * - hdev must be running
+ */
+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)
+{
+ /* Only queue command if hdev is running which means it had been opened
+ * and is either on init phase or is already up.
+ */
+ if (!test_bit(HCI_RUNNING, &hdev->flags))
+ return -ENETDOWN;
+
+ return hci_cmd_sync_submit(hdev, func, data, destroy);
+}
EXPORT_SYMBOL(hci_cmd_sync_queue);

int hci_update_eir_sync(struct hci_dev *hdev)
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a657dc1d4ec7a..732b6cf45fbe4 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -1402,11 +1402,15 @@ static int set_powered(struct sock *sk, struct hci_dev *hdev, void *data,
}

/* Cancel potentially blocking sync operation before power off */
- if (cp->val == 0x00)
+ if (cp->val == 0x00) {
__hci_cmd_sync_cancel(hdev, -EHOSTDOWN);
-
- err = hci_cmd_sync_queue(hdev, set_powered_sync, cmd,
- mgmt_set_powered_complete);
+ err = hci_cmd_sync_queue(hdev, set_powered_sync, cmd,
+ mgmt_set_powered_complete);
+ } else {
+ /* Use hci_cmd_sync_submit since hdev might not be running */
+ err = hci_cmd_sync_submit(hdev, set_powered_sync, cmd,
+ mgmt_set_powered_complete);
+ }

if (err < 0)
mgmt_pending_remove(cmd);
--
2.43.0