[PATCH 6.0 120/157] net: mdiobus: fix double put fwnode in the error path

Greg Kroah-Hartman
2022-12-12T13:46:45Z

From: Yang Yingliang <yangyingliang@huawei.com>

[ Upstream commit 165df24186ecea95705505627df3dacf5e7ff6bf ]

If phy_device_register() or fwnode_mdiobus_phy_device_register()
fail, phy_device_free() is called, the device refcount is decreased
to 0, then fwnode_handle_put() will be called in phy_device_release(),
but in the error path, fwnode_handle_put() has already been called,
so set fwnode to NULL after fwnode_handle_put() in the error path to
avoid double put.

Fixes: cdde1560118f ("net: mdiobus: fix unbalanced node reference count")
Reported-by: Zeng Heng <zengheng4@huawei.com>
Tested-by: Zeng Heng <zengheng4@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Zeng Heng <zengheng4@huawei.com>
Tested-by: Zeng Heng <zengheng4@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/mdio/fwnode_mdio.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/mdio/fwnode_mdio.c b/drivers/net/mdio/fwnode_mdio.c
index 403b07f8ec2c..2c47efdae73b 100644
--- a/drivers/net/mdio/fwnode_mdio.c
+++ b/drivers/net/mdio/fwnode_mdio.c
@@ -77,6 +77,7 @@ int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio,
*/
rc = phy_device_register(phy);
if (rc) {
+ device_set_node(&phy->mdio.dev, NULL);
fwnode_handle_put(child);
return rc;
}
@@ -125,7 +126,8 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
/* All data is now stored in the phy struct, so register it */
rc = phy_device_register(phy);
if (rc) {
- fwnode_handle_put(phy->mdio.dev.fwnode);
+ phy->mdio.dev.fwnode = NULL;
+ fwnode_handle_put(child);
goto clean_phy;
}
} else if (is_of_node(child)) {
--
2.35.1