Re: [PATCH v2] usb: typec: fix pm usage counter imbalance in ucsi_ccg_sync_control()

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Tue, Jan 07, 2025 at 09:57:50AM +0800, GONG Ruiqi wrote:
> The error handling for the case `con_index == 0` should involve dropping
> the pm usage counter, as ucsi_ccg_sync_control() gets it at the
> beginning. Fix it.
> 
> Cc: stable@vger.kernel.org
> Fixes: e56aac6e5a25 ("usb: typec: fix potential array underflow in ucsi_ccg_sync_control()")
> Signed-off-by: GONG Ruiqi <gongruiqi1@huawei.com>
> Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>

Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>

> ---
> 
> v2: complement `Cc: stable` as requested
> v1: https://lore.kernel.org/all/20241230093523.1237231-1-gongruiqi1@huawei.com/
> 
>  drivers/usb/typec/ucsi/ucsi_ccg.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
> index fcb8e61136cf..740171f24ef9 100644
> --- a/drivers/usb/typec/ucsi/ucsi_ccg.c
> +++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
> @@ -646,7 +646,7 @@ static int ucsi_ccg_sync_control(struct ucsi *ucsi, u64 command)
>  			UCSI_CMD_CONNECTOR_MASK;
>  		if (con_index == 0) {
>  			ret = -EINVAL;
> -			goto unlock;
> +			goto err_put;
>  		}
>  		con = &uc->ucsi->connector[con_index - 1];
>  		ucsi_ccg_update_set_new_cam_cmd(uc, con, &command);
> @@ -654,8 +654,8 @@ static int ucsi_ccg_sync_control(struct ucsi *ucsi, u64 command)
>  
>  	ret = ucsi_sync_control_common(ucsi, command);
>  
> +err_put:
>  	pm_runtime_put_sync(uc->dev);
> -unlock:
>  	mutex_unlock(&uc->lock);
>  
>  	return ret;
> -- 
> 2.25.1

-- 
heikki