[PATCH v2] irqchip/gic-v2m: Fix refcount leak in gicv2m_of_init

[PATCH v2] irqchip/gic-v2m: Fix refcount leak in gicv2m_of_init

[Ma Ke]

Add the missing of_node_put() to release the refcount incremented
by of_find_matching_node().

Cc: stable@vger.kernel.org
Fixes: 4266ab1a8ff5 ("irqchip/gic-v2m: Refactor to prepare for ACPI support")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
---
Changes in v2:
- modified the patch according to suggestions.
---
 drivers/irqchip/irq-gic-v2m.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c
index 51af63c046ed..d5988012eb40 100644
--- a/drivers/irqchip/irq-gic-v2m.c
+++ b/drivers/irqchip/irq-gic-v2m.c
@@ -407,12 +407,12 @@ static int __init gicv2m_of_init(struct fwnode_handle *parent_handle,
 
 		ret = gicv2m_init_one(&child->fwnode, spi_start, nr_spis,
 				      &res, 0);
-		if (ret) {
-			of_node_put(child);
+		if (ret)
 			break;
-		}
 	}
 
+	if (ret && child)
+		of_put_node(child);
 	if (!ret)
 		ret = gicv2m_allocate_domains(parent);
 	if (ret)
-- 
2.25.1

Re: [PATCH v2] irqchip/gic-v2m: Fix refcount leak in gicv2m_of_init

[Marc Zyngier]

On Tue, 20 Aug 2024 08:54:01 +0100,
Ma Ke <make24@iscas.ac.cn> wrote:
> 
> Add the missing of_node_put() to release the refcount incremented
> by of_find_matching_node().

This doesn't reflect the patch anymore. Something like this should be
closer to reality:

"We fail to perform an of_node_put() when of_address_to_resource()
fails, leading to a refcount leak.

Address this by moving the error handling path outside of the loop and
making it common to all failure modes."

With the commit message fixed:

Reviewed-by: Marc Zyngier <maz@kernel.org>

	M.

-- 
Without deviation from the norm, progress is not possible.