[PATCH AUTOSEL 5.10 30/47] PCI: mediatek: Add missing of_node_put() to fix reference leak

Sasha Levin
2021-03-02T13:34:36Z

From: Krzysztof Wilczyński <kw@linux.com>

[ Upstream commit 42814c438aac79746d310f413a27d5b0b959c5de ]

The for_each_available_child_of_node helper internally makes use of the
of_get_next_available_child() which performs an of_node_get() on each
iteration when searching for next available child node.

Should an available child node be found, then it would return a device
node pointer with reference count incremented, thus early return from
the middle of the loop requires an explicit of_node_put() to prevent
reference count leak.

To stop the reference leak, explicitly call of_node_put() before
returning after an error occurred.

Link: https://lore.kernel.org/r/20210120184810.3068794-1-kw@linux.com
Signed-off-by: Krzysztof Wilczyński <kw@linux.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pci/controller/pcie-mediatek.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/pcie-mediatek.c b/drivers/pci/controller/pcie-mediatek.c
index cf4c18f0c25a..23548b517e4b 100644
--- a/drivers/pci/controller/pcie-mediatek.c
+++ b/drivers/pci/controller/pcie-mediatek.c
@@ -1035,14 +1035,14 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
err = of_pci_get_devfn(child);
if (err < 0) {
dev_err(dev, "failed to parse devfn: %d\n", err);
- return err;
+ goto error_put_node;
}

slot = PCI_SLOT(err);

err = mtk_pcie_parse_port(pcie, child, slot);
if (err)
- return err;
+ goto error_put_node;
}

err = mtk_pcie_subsys_powerup(pcie);
@@ -1058,6 +1058,9 @@ static int mtk_pcie_setup(struct mtk_pcie *pcie)
mtk_pcie_subsys_powerdown(pcie);

return 0;
+error_put_node:
+ of_node_put(child);
+ return err;
}

static int mtk_pcie_probe(struct platform_device *pdev)
--
2.30.1