[PATCH net v2] net:thunderx:Fix resource leaks in device_for_each_child_node() loops

[PATCH net v2] net:thunderx:Fix resource leaks in device_for_each_child_node() loops

[Wang Ming]

The device_for_each_child_node() loop in
bgx_init_of_phy() function should have
wnode_handle_put() before break
which could avoid resource leaks.
This patch could fix this bug.

Signed-off-by: Wang Ming <machel@vivo.com>
---
 drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
index a317feb8decb..dad32d36a015 100644
--- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
+++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
@@ -1478,8 +1478,10 @@ static int bgx_init_of_phy(struct bgx *bgx)
 		 * cannot handle it, so exit the loop.
 		 */
 		node = to_of_node(fwn);
-		if (!node)
+		if (!node) {
+			fwnode_handle_put(fwn);
 			break;
+		}
 
 		of_get_mac_address(node, bgx->lmac[lmac].mac);
 
@@ -1503,6 +1505,7 @@ static int bgx_init_of_phy(struct bgx *bgx)
 		lmac++;
 		if (lmac == bgx->max_lmac) {
 			of_node_put(node);
+			fwnode_handle_put(fwn);
 			break;
 		}
 	}
-- 
2.25.1

Re: [PATCH net v2] net:thunderx:Fix resource leaks in device_for_each_child_node() loops

[Leon Romanovsky]

On Wed, Jul 05, 2023 at 10:34:56PM +0800, Wang Ming wrote:
> The device_for_each_child_node() loop in
> bgx_init_of_phy() function should have
> wnode_handle_put() before break
> which could avoid resource leaks.
> This patch could fix this bug.

It is very strange typographic. You have ~80 chars per-line, while your
longest line is 40 chars only.

> 
> Signed-off-by: Wang Ming <machel@vivo.com>
> ---
>  drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> index a317feb8decb..dad32d36a015 100644
> --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> @@ -1478,8 +1478,10 @@ static int bgx_init_of_phy(struct bgx *bgx)
>  		 * cannot handle it, so exit the loop.
>  		 */
>  		node = to_of_node(fwn);
> -		if (!node)
> +		if (!node) {
> +			fwnode_handle_put(fwn);
>  			break;
> +		}
>  
>  		of_get_mac_address(node, bgx->lmac[lmac].mac);
>  
> @@ -1503,6 +1505,7 @@ static int bgx_init_of_phy(struct bgx *bgx)
>  		lmac++;
>  		if (lmac == bgx->max_lmac) {
>  			of_node_put(node);
> +			fwnode_handle_put(fwn);
>  			break;
>  		}
>  	}
> -- 
> 2.25.1
> 
> 

Re: [PATCH net v2] net:thunderx:Fix resource leaks in device_for_each_child_node() loops

[Benjamin Poirier]

On 2023-07-05 22:34 +0800, Wang Ming wrote:
> The device_for_each_child_node() loop in
> bgx_init_of_phy() function should have
> wnode_handle_put() before break
 ^
 fwnode_handle_put()

> which could avoid resource leaks.
> This patch could fix this bug.
> 
> Signed-off-by: Wang Ming <machel@vivo.com>
> ---
>  drivers/net/ethernet/cavium/thunder/thunder_bgx.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> index a317feb8decb..dad32d36a015 100644
> --- a/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> +++ b/drivers/net/ethernet/cavium/thunder/thunder_bgx.c
> @@ -1478,8 +1478,10 @@ static int bgx_init_of_phy(struct bgx *bgx)
>  		 * cannot handle it, so exit the loop.
>  		 */
>  		node = to_of_node(fwn);
> -		if (!node)
> +		if (!node) {
> +			fwnode_handle_put(fwn);
>  			break;
> +		}

Fixes: eee326fd8334 ("net: thunderx: bgx: Use standard firmware node infrastructure.")
?

>  
>  		of_get_mac_address(node, bgx->lmac[lmac].mac);
>  
> @@ -1503,6 +1505,7 @@ static int bgx_init_of_phy(struct bgx *bgx)
>  		lmac++;
>  		if (lmac == bgx->max_lmac) {
>  			of_node_put(node);
> +			fwnode_handle_put(fwn);

\ fwnode_handle_put
	\ of_fwnode_put
		of_node_put(to_of_node(fwnode));

With your patch, there are now two references released on 'node' (two
of_node_put(node) calls).
One reference is from device_for_each_child_node(), where was the other
reference taken?