[PATCH] firmware: arm_scmi: Avoid leak OF node on error

cgel.zte@gmail.com posted 1 patch 1 year, 10 months ago
drivers/firmware/arm_scmi/smc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
[PATCH] firmware: arm_scmi: Avoid leak OF node on error
Posted by cgel.zte@gmail.com 1 year, 10 months ago
From: Minghao Chi <chi.minghao@zte.com.cn>

The OF node should be put before returning error in smc_chan_available(),
otherwise node's refcount will be leaked.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
---
 drivers/firmware/arm_scmi/smc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
index 745acfdd0b3d..43018be70edc 100644
--- a/drivers/firmware/arm_scmi/smc.c
+++ b/drivers/firmware/arm_scmi/smc.c
@@ -55,10 +55,10 @@ static irqreturn_t smc_msg_done_isr(int irq, void *data)
 static bool smc_chan_available(struct device *dev, int idx)
 {
 	struct device_node *np = of_parse_phandle(dev->of_node, "shmem", 0);
+	of_node_put(np);
 	if (!np)
 		return false;
 
-	of_node_put(np);
 	return true;
 }
 
-- 
2.25.1
Re: [PATCH] firmware: arm_scmi: Avoid leak OF node on error
Posted by Sudeep Holla 1 year, 10 months ago
On Mon, May 23, 2022 at 11:11:16AM +0000, cgel.zte@gmail.com wrote:
> From: Minghao Chi <chi.minghao@zte.com.cn>
> 
> The OF node should be put before returning error in smc_chan_available(),
> otherwise node's refcount will be leaked.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
> ---
>  drivers/firmware/arm_scmi/smc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
> index 745acfdd0b3d..43018be70edc 100644
> --- a/drivers/firmware/arm_scmi/smc.c
> +++ b/drivers/firmware/arm_scmi/smc.c
> @@ -55,10 +55,10 @@ static irqreturn_t smc_msg_done_isr(int irq, void *data)
>  static bool smc_chan_available(struct device *dev, int idx)
>  {
>  	struct device_node *np = of_parse_phandle(dev->of_node, "shmem", 0);
> +	of_node_put(np);

While this may work as of_node_put handles NULL as argument, what is the
point of unnecessary of_node_put(NULL) here ?

-- 
Regards,
Sudeep
Re: [PATCH] firmware: arm_scmi: Avoid leak OF node on error
Posted by Johan Hovold 1 year, 10 months ago
On Mon, May 23, 2022 at 11:11:16AM +0000, cgel.zte@gmail.com wrote:
> From: Minghao Chi <chi.minghao@zte.com.cn>
> 
> The OF node should be put before returning error in smc_chan_available(),
> otherwise node's refcount will be leaked.
> 
> Reported-by: Zeal Robot <zealci@zte.com.cn>
> Signed-off-by: Minghao Chi <chi.minghao@zte.com.cn>
> ---
>  drivers/firmware/arm_scmi/smc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c
> index 745acfdd0b3d..43018be70edc 100644
> --- a/drivers/firmware/arm_scmi/smc.c
> +++ b/drivers/firmware/arm_scmi/smc.c
> @@ -55,10 +55,10 @@ static irqreturn_t smc_msg_done_isr(int irq, void *data)
>  static bool smc_chan_available(struct device *dev, int idx)
>  {
>  	struct device_node *np = of_parse_phandle(dev->of_node, "shmem", 0);
> +	of_node_put(np);
>  	if (!np)
>  		return false;
>  
> -	of_node_put(np);
>  	return true;
>  }

NAK