net: mdiobus: fix double put fwnode in the error path

If phy_device_register() or fwnode_mdiobus_phy_device_register()
fail, phy_device_free() is called, the device refcount is decreased
to 0, then

net: mdiobus: fix double put fwnode in the error path

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>

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net: mdiobus: fix unbalanced node reference count

I got the following report while doing device(mscc-miim) load test
with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled:

OF: ERROR: memory leak,

net: mdiobus: fix unbalanced node reference count

I got the following report while doing device(mscc-miim) load test
with CONFIG_OF_UNITTEST and CONFIG_OF_DYNAMIC enabled:

OF: ERROR: memory leak, expected refcount 1 instead of 2,
of_node_get()/of_node_put() unbalanced - destroy cset entry:
attach overlay node /spi/soc@0/mdio@7107009c/ethernet-phy@0

If the 'fwnode' is not an acpi node, the refcount is get in
fwnode_mdiobus_phy_device_register(), but it has never been
put when the device is freed in the normal path. So call
fwnode_handle_put() in phy_device_release() to avoid leak.

If it's an acpi node, it has never been get, but it's put
in the error path, so call fwnode_handle_get() before
phy_device_register() to keep get/put operation balanced.

Fixes: bc1bee3b87ee ("net: mdiobus: Introduce fwnode_mdiobus_register_phy()")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20221124150130.609420-1-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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