nfc: nci: fix the UAF of rf_conn_info object

The nci_core_conn_close_rsp_packet() function will release the conn_info
with given conn_id. However, it needs to set the rf_conn_info to NULL to
prevent other routines like nci_rf_intf_activated_ntf_packet() to trigger
the UAF.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/nfc/nci/rsp.c b/net/nfc/nci/rsp.c
index a2e72c0..b911ab7 100644 (file)
--- a/net/nfc/nci/rsp.c
+++ b/net/nfc/nci/rsp.c
@@ -334,6 +334,8 @@ static void nci_core_conn_close_rsp_packet(struct nci_dev *ndev,
                                                         ndev->cur_conn_id);
                if (conn_info) {
                        list_del(&conn_info->list);
+                       if (conn_info == ndev->rf_conn_info)
+                               ndev->rf_conn_info = NULL;
                        devm_kfree(&ndev->nfc_dev->dev, conn_info);
                }
        }