[PATCH] nfc: nci: fix the UAF of rf_conn_info object

From: Krzysztof Kozlowski
Date: Thu Oct 07 2021 - 13:45:06 EST


From: Lin Ma <linma@xxxxxxxxxx>

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@xxxxxxxxxxxxx>
Signed-off-by: Lin Ma <linma@xxxxxxxxxx>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxxxxx>
---
net/nfc/nci/rsp.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/nfc/nci/rsp.c b/net/nfc/nci/rsp.c
index a2e72c003805..b911ab78bed9 100644
--- 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);
}
}
--
2.30.2