[PATCH] usb: core: add missing of_node_put() in usb_of_has_devices_or_graph

From: Javier Carrasco
Date: Mon Jun 24 2024 - 17:10:31 EST


The for_each_child_of_node() macro requires an explicit call to
of_node_put() on early exits to decrement the child refcount and avoid a
memory leak.
The child node is not required outsie the loop, and the resource must be
released before the function returns.

Add the missing of_node_put().

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 82e82130a78b ("usb: core: Set connect_type of ports based on DT node")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>
---
This bug was found while doing some code analysis, and I could not test
it with real hardware. Although the issue and it solution are
straightforward, any validation beyond compilation and static analysis
is always welcome.
---
drivers/usb/core/of.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/core/of.c b/drivers/usb/core/of.c
index f1a499ee482c..763e4122ed5b 100644
--- a/drivers/usb/core/of.c
+++ b/drivers/usb/core/of.c
@@ -84,9 +84,12 @@ static bool usb_of_has_devices_or_graph(const struct usb_device *hub)
if (of_graph_is_present(np))
return true;

- for_each_child_of_node(np, child)
- if (of_property_present(child, "reg"))
+ for_each_child_of_node(np, child) {
+ if (of_property_present(child, "reg")) {
+ of_node_put(child);
return true;
+ }
+ }

return false;
}

---
base-commit: 62c97045b8f720c2eac807a5f38e26c9ed512371
change-id: 20240624-usb_core_of_memleak-79161623b62e

Best regards,
--
Javier Carrasco <javier.carrasco.cruz@xxxxxxxxx>