From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
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@xxxxxxxxxxxxxxx
Reviewed-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
---
The following kernel mainline commit fixes a similar issue:
Commit: b337cc3ce475 ("backlight: lm3509_bl: Fix early returns in for_each_child_of_node()")
---
drivers/phy/phy-core.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index b88fbda6c046174b7abd0a0435ec54763e9f42bc..413f76e2d1744dd8ffb63a6c3a093f5c6cbead7b 100644
--- 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);
--
2.34.1
