[PATCH 6.0 0675/1073] usb: typec: tcpci: fix of node refcount leak in tcpci_register_port()

Greg Kroah-Hartman
2022-12-28T16:19:19Z

From: Yang Yingliang <yangyingliang@huawei.com>

[ Upstream commit 0384e87e3fec735e47f1c133c796f32ef7a72a9b ]

I got the following report while doing device(mt6370-tcpc) 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 /i2c/pmic@34/tcpc/connector

The 'fwnode' set in tcpci_parse_config() which is called
in tcpci_register_port(), its node refcount is increased
in device_get_named_child_node(). It needs be put while
exiting, so call fwnode_handle_put() in the error path of
tcpci_register_port() and in tcpci_unregister_port() to
avoid leak.

Fixes: 5e85a04c8c0d ("usb: typec: add fwnode to tcpc")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20221121062416.1026192-1-yangyingliang@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/usb/typec/tcpm/tcpci.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c
index 812784702d53..592bd4c85482 100644
--- a/drivers/usb/typec/tcpm/tcpci.c
+++ b/drivers/usb/typec/tcpm/tcpci.c
@@ -816,8 +816,10 @@ struct tcpci *tcpci_register_port(struct device *dev, struct tcpci_data *data)
return ERR_PTR(err);

tcpci->port = tcpm_register_port(tcpci->dev, &tcpci->tcpc);
- if (IS_ERR(tcpci->port))
+ if (IS_ERR(tcpci->port)) {
+ fwnode_handle_put(tcpci->tcpc.fwnode);
return ERR_CAST(tcpci->port);
+ }

return tcpci;
}
@@ -826,6 +828,7 @@ EXPORT_SYMBOL_GPL(tcpci_register_port);
void tcpci_unregister_port(struct tcpci *tcpci)
{
tcpm_unregister_port(tcpci->port);
+ fwnode_handle_put(tcpci->tcpc.fwnode);
}
EXPORT_SYMBOL_GPL(tcpci_unregister_port);

--
2.35.1