net: dpaa: fix device leak when querying time stamp info

commit 3fa840230f534385b34a4f39c8dd313fbe723f05 upstream.

Make sure to drop the reference to the ptp device taken by
of_find_device_by_node() when querying the time stamping capabilities.

Note that holding a reference to the ptp device does not prevent its
driver data from going away.

Fixes: 17ae0b0ee9db ("dpaa_eth: add the get_ts_info interface for ethtool")
Cc: stable@vger.kernel.org	# 4.19
Cc: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250725171213.880-2-johan@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c b/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
index 9986f6e1f5877478df87db152e33fa2127e939a6..7fc01baef280c0abe43e661dddd4a3069230ebd9 100644 (file)
--- a/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
+++ b/drivers/net/ethernet/freescale/dpaa/dpaa_ethtool.c
@@ -401,8 +401,10 @@ static int dpaa_get_ts_info(struct net_device *net_dev,
                of_node_put(ptp_node);
        }
 
-       if (ptp_dev)
+       if (ptp_dev) {
                ptp = platform_get_drvdata(ptp_dev);
+               put_device(&ptp_dev->dev);
+       }
 
        if (ptp)
                info->phc_index = ptp->phc_index;