[v1] bus: vexpress-config: Fix device node reference leak in probe

[PATCH] bus: vexpress-config: Fix device node reference leak in probe

Posted by Felix Gu 2 weeks, 2 days ago

In vexpress_syscfg_probe(), of_parse_phandle() is called inside a loop
but the returned device_node reference is never released.
Fix this by using the __free(device_node) cleanup handler to automatically
release the reference when the variable goes out of scope.

Fixes: a5a38765ac79b ("bus: vexpress-config: simplify config bus probing")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
 drivers/bus/vexpress-config.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/bus/vexpress-config.c b/drivers/bus/vexpress-config.c
index 64ee920721ee..a1fa583e9f5d 100644
--- a/drivers/bus/vexpress-config.c
+++ b/drivers/bus/vexpress-config.c
@@ -4,6 +4,7 @@
  * Copyright (C) 2014 ARM Limited
  */
 
+#include <linux/cleanup.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/io.h>
@@ -390,9 +391,8 @@ static int vexpress_syscfg_probe(struct platform_device *pdev)
 	}
 
 	for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
-		struct device_node *bridge_np;
-
-		bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
+		struct device_node *bridge_np __free(device_node) =
+			of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
 		if (bridge_np != pdev->dev.parent->of_node)
 			continue;
 

---
base-commit: 053966c344dbd346e71305f530e91ea77916189f
change-id: 20260122-b4-vexpress-config-1d2051861d93

Best regards,
-- 
Felix Gu <ustc.gu@gmail.com>

Re: [PATCH] bus: vexpress-config: Fix device node reference leak in probe

Posted by Liviu Dudau 2 weeks, 2 days ago

Hello,

On Thu, Jan 22, 2026 at 08:33:04PM +0800, Felix Gu wrote:
> In vexpress_syscfg_probe(), of_parse_phandle() is called inside a loop
> but the returned device_node reference is never released.
> Fix this by using the __free(device_node) cleanup handler to automatically
> release the reference when the variable goes out of scope.
> 
> Fixes: a5a38765ac79b ("bus: vexpress-config: simplify config bus probing")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> ---
>  drivers/bus/vexpress-config.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/bus/vexpress-config.c b/drivers/bus/vexpress-config.c
> index 64ee920721ee..a1fa583e9f5d 100644
> --- a/drivers/bus/vexpress-config.c
> +++ b/drivers/bus/vexpress-config.c
> @@ -4,6 +4,7 @@
>   * Copyright (C) 2014 ARM Limited
>   */
>  
> +#include <linux/cleanup.h>

Not sure this is needed. of.h includes cleanup.h, so we don't run the risk of
not getting the cleanup macros defined.

>  #include <linux/err.h>
>  #include <linux/init.h>
>  #include <linux/io.h>
> @@ -390,9 +391,8 @@ static int vexpress_syscfg_probe(struct platform_device *pdev)
>  	}
>  
>  	for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
> -		struct device_node *bridge_np;
> -
> -		bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
> +		struct device_node *bridge_np __free(device_node) =
> +			of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
>  		if (bridge_np != pdev->dev.parent->of_node)
>  			continue;
>

Otherwise, patch looks good to me. Thanks for the fix!

Acked-by: Liviu Dudau <liviu.dudau@arm.com>

Best regards,
Liviu

> 
> ---
> base-commit: 053966c344dbd346e71305f530e91ea77916189f
> change-id: 20260122-b4-vexpress-config-1d2051861d93
> 
> Best regards,
> -- 
> Felix Gu <ustc.gu@gmail.com>
>

Re: [PATCH] bus: vexpress-config: Fix device node reference leak in probe

Posted by Felix Gu 2 weeks, 2 days ago

Hi Liviu,
Thanks for the review.
I will remove the header file and send out V2.

Best regars,
Felix
On Thu, Jan 22, 2026 at 9:32 PM Liviu Dudau <liviu.dudau@arm.com> wrote:
>
> Hello,
>
> On Thu, Jan 22, 2026 at 08:33:04PM +0800, Felix Gu wrote:
> > In vexpress_syscfg_probe(), of_parse_phandle() is called inside a loop
> > but the returned device_node reference is never released.
> > Fix this by using the __free(device_node) cleanup handler to automatically
> > release the reference when the variable goes out of scope.
> >
> > Fixes: a5a38765ac79b ("bus: vexpress-config: simplify config bus probing")
> > Signed-off-by: Felix Gu <ustc.gu@gmail.com>
> > ---
> >  drivers/bus/vexpress-config.c | 6 +++---
> >  1 file changed, 3 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/bus/vexpress-config.c b/drivers/bus/vexpress-config.c
> > index 64ee920721ee..a1fa583e9f5d 100644
> > --- a/drivers/bus/vexpress-config.c
> > +++ b/drivers/bus/vexpress-config.c
> > @@ -4,6 +4,7 @@
> >   * Copyright (C) 2014 ARM Limited
> >   */
> >
> > +#include <linux/cleanup.h>
>
> Not sure this is needed. of.h includes cleanup.h, so we don't run the risk of
> not getting the cleanup macros defined.
>
> >  #include <linux/err.h>
> >  #include <linux/init.h>
> >  #include <linux/io.h>
> > @@ -390,9 +391,8 @@ static int vexpress_syscfg_probe(struct platform_device *pdev)
> >       }
> >
> >       for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
> > -             struct device_node *bridge_np;
> > -
> > -             bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
> > +             struct device_node *bridge_np __free(device_node) =
> > +                     of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
> >               if (bridge_np != pdev->dev.parent->of_node)
> >                       continue;
> >
>
> Otherwise, patch looks good to me. Thanks for the fix!
>
> Acked-by: Liviu Dudau <liviu.dudau@arm.com>
>
> Best regards,
> Liviu
>
> >
> > ---
> > base-commit: 053966c344dbd346e71305f530e91ea77916189f
> > change-id: 20260122-b4-vexpress-config-1d2051861d93
> >
> > Best regards,
> > --
> > Felix Gu <ustc.gu@gmail.com>
> >