phy: core: Fix an OF node refcount leakage in of_phy_provider_lookup()

For macro for_each_child_of_node(parent, child), refcount of @child has
been increased before entering its loop body, so normally needs to call
of_node_put(@child) before returning from the loop body to avoid refcount
leakage.

of_phy_provider_lookup() has such usage but does not call of_node_put()
before returning, so cause leakage of the OF node refcount.

Fix by simply calling of_node_put() before returning from the loop body.

The APIs affected by this issue are shown below since they indirectly
invoke problematic of_phy_provider_lookup().
phy_get()
of_phy_get()
devm_phy_get()
devm_of_phy_get()
devm_of_phy_get_by_index()

Fixes: 2a4c37016ca9 ("phy: core: Fix of_phy_provider_lookup to return PHY provider for sub node")
Cc: stable@vger.kernel.org
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com>
Link: https://lore.kernel.org/r/20241213-phy_core_fix-v6-5-40ae28f5015a@quicinc.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index b88fbda6c046174b7abd0a0435ec54763e9f42bc..413f76e2d1744dd8ffb63a6c3a093f5c6cbead7b 100644 (file)
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -145,8 +145,10 @@ static struct phy_provider *of_phy_provider_lookup(struct device_node *node)
                        return phy_provider;
 
                for_each_child_of_node(phy_provider->children, child)
-                       if (child == node)
+                       if (child == node) {
+                               of_node_put(child);
                                return phy_provider;
+                       }
        }
 
        return ERR_PTR(-EPROBE_DEFER);