[v1] EDAC/altera: Fix SDMMC PortB OF node reference leak

[PATCH v1] EDAC/altera: Fix SDMMC PortB OF node reference leak

Posted by Yuho Choi 1 month, 1 week ago

of_find_compatible_node() returns a device node with its refcount
incremented. altr_portb_setup() looks up the SDMMC ECC node but does
not drop that reference on error paths or after successful setup.

Route the exits after the lookup through a cleanup path that calls
of_node_put() before returning.

Fixes: 911049845d70 ("EDAC, altera: Add Arria10 SD-MMC EDAC support")
Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
---
 drivers/edac/altera_edac.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 4edd2088c2db..a2fb30a9b914 100644
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -1526,15 +1526,18 @@ static int altr_portb_setup(struct altr_edac_device_dev *device)
 		edac_printk(KERN_ERR, EDAC_DEVICE,
 			    "%s: Unable to allocate PortB EDAC device\n",
 			    ecc_name);
-		return -ENOMEM;
+		rc = -ENOMEM;
+		goto out_put_node;
 	}
 
 	/* Initialize the PortB EDAC device structure from PortA structure */
 	altdev = dci->pvt_info;
 	*altdev = *device;
 
-	if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL))
-		return -ENOMEM;
+	if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL)) {
+		rc = -ENOMEM;
+		goto out_put_node;
+	}
 
 	/* Update PortB specific values */
 	altdev->edac_dev_name = ecc_name;
@@ -1607,13 +1610,16 @@ static int altr_portb_setup(struct altr_edac_device_dev *device)
 
 	devres_remove_group(&altdev->ddev, altr_portb_setup);
 
-	return 0;
+	rc = 0;
+	goto out_put_node;
 
 err_release_group_1:
 	edac_device_free_ctl_info(dci);
 	devres_release_group(&altdev->ddev, altr_portb_setup);
 	edac_printk(KERN_ERR, EDAC_DEVICE,
 		    "%s:Error setting up EDAC device: %d\n", ecc_name, rc);
+out_put_node:
+	of_node_put(np);
 	return rc;
 }
 
-- 
2.43.0

Re: [PATCH v1] EDAC/altera: Fix SDMMC PortB OF node reference leak

Posted by Dinh Nguyen 1 month, 1 week ago

Hi Yuho,

On 5/1/26 14:48, Yuho Choi wrote:
> of_find_compatible_node() returns a device node with its refcount
> incremented. altr_portb_setup() looks up the SDMMC ECC node but does
> not drop that reference on error paths or after successful setup.
> 
> Route the exits after the lookup through a cleanup path that calls
> of_node_put() before returning.
> 
> Fixes: 911049845d70 ("EDAC, altera: Add Arria10 SD-MMC EDAC support")
> Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
> ---
>   drivers/edac/altera_edac.c | 14 ++++++++++----
>   1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> index 4edd2088c2db..a2fb30a9b914 100644
> --- a/drivers/edac/altera_edac.c
> +++ b/drivers/edac/altera_edac.c
> @@ -1526,15 +1526,18 @@ static int altr_portb_setup(struct altr_edac_device_dev *device)
>   		edac_printk(KERN_ERR, EDAC_DEVICE,
>   			    "%s: Unable to allocate PortB EDAC device\n",
>   			    ecc_name);
> -		return -ENOMEM;
> +		rc = -ENOMEM;
> +		goto out_put_node;
>   	}
>   
>   	/* Initialize the PortB EDAC device structure from PortA structure */
>   	altdev = dci->pvt_info;
>   	*altdev = *device;
>   
> -	if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL))
> -		return -ENOMEM;
> +	if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL)) {
> +		rc = -ENOMEM;
> +		goto out_put_node;

I think this should goto err_release_group_1, otherwise the dci pointer 
is leaked.

Dinh

Re: [PATCH v1] EDAC/altera: Fix SDMMC PortB OF node reference leak

Posted by 최유호 1 month, 1 week ago

Dear Dinh,

Thanks for catching that dci leak. I will update the goto path in v2.

Yuho

On Fri, 1 May 2026 at 18:26, Dinh Nguyen <dinguyen@kernel.org> wrote:
>
> Hi Yuho,
>
> On 5/1/26 14:48, Yuho Choi wrote:
> > of_find_compatible_node() returns a device node with its refcount
> > incremented. altr_portb_setup() looks up the SDMMC ECC node but does
> > not drop that reference on error paths or after successful setup.
> >
> > Route the exits after the lookup through a cleanup path that calls
> > of_node_put() before returning.
> >
> > Fixes: 911049845d70 ("EDAC, altera: Add Arria10 SD-MMC EDAC support")
> > Signed-off-by: Yuho Choi <dbgh9129@gmail.com>
> > ---
> >   drivers/edac/altera_edac.c | 14 ++++++++++----
> >   1 file changed, 10 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
> > index 4edd2088c2db..a2fb30a9b914 100644
> > --- a/drivers/edac/altera_edac.c
> > +++ b/drivers/edac/altera_edac.c
> > @@ -1526,15 +1526,18 @@ static int altr_portb_setup(struct altr_edac_device_dev *device)
> >               edac_printk(KERN_ERR, EDAC_DEVICE,
> >                           "%s: Unable to allocate PortB EDAC device\n",
> >                           ecc_name);
> > -             return -ENOMEM;
> > +             rc = -ENOMEM;
> > +             goto out_put_node;
> >       }
> >
> >       /* Initialize the PortB EDAC device structure from PortA structure */
> >       altdev = dci->pvt_info;
> >       *altdev = *device;
> >
> > -     if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL))
> > -             return -ENOMEM;
> > +     if (!devres_open_group(&altdev->ddev, altr_portb_setup, GFP_KERNEL)) {
> > +             rc = -ENOMEM;
> > +             goto out_put_node;
>
> I think this should goto err_release_group_1, otherwise the dci pointer
> is leaked.
>
> Dinh
>
>