[PATCH] net: stmmac: Fix MDIO node leak in stmmac_mdio_setup()

[Wentao Liang]

stmmac_mdio_setup() acquires a reference on the MDIO node through
stmmac_of_get_mdio() and stores it in plat->mdio_node. If the allocation
of plat->mdio_bus_data fails, the function returns -ENOMEM and the
caller takes the error_put_phy path, which only releases plat->phy_node,
so the MDIO node reference is leaked.

Release plat->mdio_node on this error path.

Fixes: 1a981c0586c0 ("net: stmmac: Make MDIO bus reset optional")
Cc: stable at vger.kernel.org
Signed-off-by: Wentao Liang <vulab at iscas.ac.cn>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
index 5cae2aa72906..09359ccb32ef 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
@@ -356,8 +356,11 @@ static int stmmac_mdio_setup(struct plat_stmmacenet_data *plat,
 		plat->mdio_bus_data = devm_kzalloc(dev,
 						   sizeof(*plat->mdio_bus_data),
 						   GFP_KERNEL);
-		if (!plat->mdio_bus_data)
+		if (!plat->mdio_bus_data) {
+			of_node_put(plat->mdio_node);
+			plat->mdio_node = NULL;
 			return -ENOMEM;
+		}
 
 		plat->mdio_bus_data->needs_reset = true;
 	}
-- 
2.34.1