can: flexcan: Fix OF node reference leak in flexcan_setup_stop_mode_gpr()

[PATCH] can: flexcan: Fix OF node reference leak in flexcan_setup_stop_mode_gpr()

Posted by Wentao Liang 1 week ago

of_find_node_by_phandle() takes a reference on the GPR node and the
error path releases it through out_put_node.  The success path returns
before reaching that label, so the reference is leaked every time the
stop mode is set up successfully, and the node can never be freed.

Release the node reference before returning.

Fixes: 13dfb3fa4943 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/net/can/flexcan/flexcan-core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
index f5d22c61503f..68699d674fc3 100644
--- a/drivers/net/can/flexcan/flexcan-core.c
+++ b/drivers/net/can/flexcan/flexcan-core.c
@@ -1986,6 +1986,7 @@ static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
 		"gpr %s req_gpr=0x02%x req_bit=%u\n",
 		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
 
+	of_node_put(gpr_np);
 	return 0;
 
 out_put_node:
-- 
2.34.1

Re: [PATCH] can: flexcan: Fix OF node reference leak in flexcan_setup_stop_mode_gpr()

Posted by Marc Kleine-Budde 1 week ago

On 17.09.2026 09:53:02, Wentao Liang wrote:
> of_find_node_by_phandle() takes a reference on the GPR node and the
> error path releases it through out_put_node.  The success path returns
> before reaching that label, so the reference is leaked every time the
> stop mode is set up successfully, and the node can never be freed.
>
> Release the node reference before returning.
>
> Fixes: 13dfb3fa4943 ("Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net")

A merge commit probably has not introduced this problem...

Marc

> Cc: stable@vger.kernel.org
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
> ---
>  drivers/net/can/flexcan/flexcan-core.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/net/can/flexcan/flexcan-core.c b/drivers/net/can/flexcan/flexcan-core.c
> index f5d22c61503f..68699d674fc3 100644
> --- a/drivers/net/can/flexcan/flexcan-core.c
> +++ b/drivers/net/can/flexcan/flexcan-core.c
> @@ -1986,6 +1986,7 @@ static int flexcan_setup_stop_mode_gpr(struct platform_device *pdev)
>  		"gpr %s req_gpr=0x02%x req_bit=%u\n",
>  		gpr_np->full_name, priv->stm.req_gpr, priv->stm.req_bit);
>
> +	of_node_put(gpr_np);
>  	return 0;
>
>  out_put_node:
> --
> 2.34.1
>
>

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