Bluetooth: Prevent out-of-bounds read in hci_inquiry_result_with_rssi_evt()

Check `num_rsp` before using it as for-loop counter. Add `unlock` label.

Cc: [email protected]
Signed-off-by: Peilin Ye <[email protected]>
Signed-off-by: Marcel Holtmann <[email protected]>

Author: peilin-ye

net/bluetooth/hci_event.c

@@ -4159,6 +4159,9 @@ static void hci_inquiry_result_with_rssi_evt(struct hci_dev *hdev,
 		struct inquiry_info_with_rssi_and_pscan_mode *info;
 		info = (void *) (skb->data + 1);
 
+		if (skb->len < num_rsp * sizeof(*info) + 1)
+			goto unlock;
+
 		for (; num_rsp; num_rsp--, info++) {
 			u32 flags;
 
@@ -4180,6 +4183,9 @@ static void hci_inquiry_result_with_rssi_evt(struct hci_dev *hdev,
 	} else {
 		struct inquiry_info_with_rssi *info = (void *) (skb->data + 1);
 
+		if (skb->len < num_rsp * sizeof(*info) + 1)
+			goto unlock;
+
 		for (; num_rsp; num_rsp--, info++) {
 			u32 flags;
 
@@ -4200,6 +4206,7 @@ static void hci_inquiry_result_with_rssi_evt(struct hci_dev *hdev,
 		}
 	}
 
+unlock:
 	hci_dev_unlock(hdev);
 }