[PATCH] fix: net: cadence: macb_mii_init: fix double of_node_put on mdio_np after macb_mdiobus_register

[WenTao Liang]

After macb_mdiobus_register succeeds, the mdio_np reference ownership is
  transferred to the mii_bus device (stored in mii_bus->dev.of_node). When
  the subsequent macb_mii_probe fails, the error path jumps to
  err_out_unregister_bus which calls mdiobus_free (releasing the node via
  fwnode_handle_put) and then falls through to err_out which calls
  of_node_put(mdio_np) again, causing a double put.

Move the of_node_put to only execute on paths where the reference was not
  transferred (i.e., before successful macb_mdiobus_register).

Cc: stable@xxxxxxxxxxxxxxx
Fixes: ef8a2e27289e ("net: macb: fix probing of PHY not described in the dt")
Signed-off-by: WenTao Liang <vulab@xxxxxxxxxxx>
---
 drivers/net/ethernet/cadence/macb_main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index a12aa21244e8..c58e089e5888 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -1170,6 +1170,9 @@ static int macb_mii_init(struct macb *bp)
 	mdiobus_unregister(bp->mii_bus);
 err_out_free_mdiobus:
 	mdiobus_free(bp->mii_bus);
+	of_node_put(mdio_np);
+	return err;
+
 err_out:
 	of_node_put(mdio_np);
 
-- 
2.39.5 (Apple Git-154)