[PATCH 4.14 033/106] PCI: aardvark: Fix a leaked reference by adding missing of_node_put()

Greg Kroah-Hartman
2021-12-06T15:14:07Z

From: Wen Yang <wen.yang99@zte.com.cn>

commit 3842f5166bf1ef286fe7a39f262b5c9581308366 upstream.

The call to of_get_next_child() returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

irq_domain_add_linear() also calls of_node_get() to increase refcount,
so irq_domain will not be affected when it is released.

Detected by coccinelle with the following warnings:
./drivers/pci/controller/pci-aardvark.c:826:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 798, but without a corresponding object release within this function.

Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: linux-pci@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/pci/host/pci-aardvark.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- a/drivers/pci/host/pci-aardvark.c
+++ b/drivers/pci/host/pci-aardvark.c
@@ -789,6 +789,7 @@ static int advk_pcie_init_irq_domain(str
struct device_node *node = dev->of_node;
struct device_node *pcie_intc_node;
struct irq_chip *irq_chip;
+ int ret = 0;

raw_spin_lock_init(&pcie->irq_lock);

@@ -803,8 +804,8 @@ static int advk_pcie_init_irq_domain(str
irq_chip->name = devm_kasprintf(dev, GFP_KERNEL, "%s-irq",
dev_name(dev));
if (!irq_chip->name) {
- of_node_put(pcie_intc_node);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_put_node;
}

irq_chip->irq_mask = advk_pcie_irq_mask;
@@ -816,11 +817,13 @@ static int advk_pcie_init_irq_domain(str
&advk_pcie_irq_domain_ops, pcie);
if (!pcie->irq_domain) {
dev_err(dev, "Failed to get a INTx IRQ domain\n");
- of_node_put(pcie_intc_node);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_put_node;
}

- return 0;
+out_put_node:
+ of_node_put(pcie_intc_node);
+ return ret;
}

static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie)