[PATCH] Bluetooth: hci_sync: Avoid use-after-free in dbg for hci_add_adv_monitor()

From: Manish Mandlik
Date: Fri Aug 04 2023 - 14:15:04 EST


KSAN reports use-after-free in hci_add_adv_monitor().

While adding an adv monitor,
hci_add_adv_monitor() calls ->
msft_add_monitor_pattern() calls ->
msft_add_monitor_sync() calls ->
msft_le_monitor_advertisement_cb() calls in an error case ->
hci_free_adv_monitor() which frees the *moniter.

This is referenced by bt_dev_dbg() in hci_add_adv_monitor().

Fix the bt_dev_dbg() by using handle instead of monitor->handle.

Fixes: b747a83690c8 ("Bluetooth: hci_sync: Refactor add Adv Monitor")

Signed-off-by: Manish Mandlik <mmandlik@xxxxxxxxxx>
---

net/bluetooth/hci_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 0fefa6788911..c602cfb5be9e 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1957,7 +1957,7 @@ int hci_add_adv_monitor(struct hci_dev *hdev, struct adv_monitor *monitor)
case HCI_ADV_MONITOR_EXT_MSFT:
status = msft_add_monitor_pattern(hdev, monitor);
bt_dev_dbg(hdev, "add monitor %d msft status %d",
- monitor->handle, status);
+ handle, status);
break;
}

--
2.41.0.585.gd2178a4bd4-goog