[PATCH v2 25/26] staging: wilc1000: refactor wilc_netdev_init() to handle memory free in error path

Claudiu Beznea Claudiu.Beznea at microchip.com
Tue Sep 11 09:21:13 UTC 2018



On 04.09.2018 09:39, Ajay Singh wrote:
> Refactor the wilc_netdev_init() to cleanup the memory for error
> scenario and remove unnecessary 'dev' pointer check.
> 
> Signed-off-by: Ajay Singh <ajay.kathat at microchip.com>
> ---
>  drivers/staging/wilc1000/linux_wlan.c             | 36 ++++++++++++++++-------
>  drivers/staging/wilc1000/wilc_wfi_cfgoperations.c |  6 +++-
>  2 files changed, 30 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/staging/wilc1000/linux_wlan.c b/drivers/staging/wilc1000/linux_wlan.c
> index d7d43fd..91a45a7 100644
> --- a/drivers/staging/wilc1000/linux_wlan.c
> +++ b/drivers/staging/wilc1000/linux_wlan.c
> @@ -1073,10 +1073,8 @@ int wilc_netdev_init(struct wilc **wilc, struct device *dev, int io_type,
>  	INIT_LIST_HEAD(&wl->rxq_head.list);
>  
>  	wl->hif_workqueue = create_singlethread_workqueue("WILC_wq");
> -	if (!wl->hif_workqueue) {
> -		kfree(wl);
> -		return -ENOMEM;
> -	}
> +	if (!wl->hif_workqueue)
> +		goto free_wl;
>  
>  	register_inetaddr_notifier(&g_dev_notifier);
>  
> @@ -1085,7 +1083,7 @@ int wilc_netdev_init(struct wilc **wilc, struct device *dev, int io_type,
>  
>  		ndev = alloc_etherdev(sizeof(struct wilc_vif));
>  		if (!ndev)
> -			return -ENOMEM;
> +			goto free_ndev;
>  
>  		vif = netdev_priv(ndev);
>  		memset(vif, 0, sizeof(struct wilc_vif));
> @@ -1106,15 +1104,13 @@ int wilc_netdev_init(struct wilc **wilc, struct device *dev, int io_type,
>  		ndev->netdev_ops = &wilc_netdev_ops;
>  
>  		wdev = wilc_create_wiphy(ndev, dev);
> -
> -		if (dev)
> -			SET_NETDEV_DEV(ndev, dev);
> -
>  		if (!wdev) {
>  			netdev_err(ndev, "Can't register WILC Wiphy\n");
> -			return -1;
> +			goto free_ndev;
>  		}
>  
> +		SET_NETDEV_DEV(ndev, dev);
> +
>  		vif->ndev->ieee80211_ptr = wdev;
>  		vif->ndev->ml_priv = vif;
>  		wdev->netdev = vif->ndev;
> @@ -1125,11 +1121,29 @@ int wilc_netdev_init(struct wilc **wilc, struct device *dev, int io_type,
>  
>  		ret = register_netdev(ndev);
>  		if (ret)
> -			return ret;
> +			goto free_ndev;

In case this happens you will loose the return code of register_netdev()
and you will return instead -ENOMEM. Maybe, the best approach will be to
initialize ret = -ENOMEM while declaring it

>  
>  		vif->iftype = STATION_MODE;
>  		vif->mac_opened = 0;
>  	}
>  
>  	return 0;
> +
> +free_ndev:
> +	for (; i >= 0; i--) {
> +		if (wl->vif[i]) {
> +			if (wl->vif[i]->iftype == STATION_MODE)
> +				unregister_netdev(wl->vif[i]->ndev);
> +
> +			if (wl->vif[i]->ndev) {
> +				wilc_free_wiphy(wl->vif[i]->ndev);
> +				free_netdev(wl->vif[i]->ndev);
> +			}
> +		}
> +	}
> +	unregister_inetaddr_notifier(&g_dev_notifier);
> +	destroy_workqueue(wl->hif_workqueue);
> +free_wl:
> +	kfree(wl);
> +	return -ENOMEM;

and here to just return ret.

>  }
> diff --git a/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c b/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
> index d103dce2..37c26d4 100644
> --- a/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
> +++ b/drivers/staging/wilc1000/wilc_wfi_cfgoperations.c
> @@ -2145,8 +2145,12 @@ struct wireless_dev *wilc_create_wiphy(struct net_device *net,
>  	set_wiphy_dev(wdev->wiphy, dev);
>  
>  	ret = wiphy_register(wdev->wiphy);
> -	if (ret)
> +	if (ret) {
>  		netdev_err(net, "Cannot register wiphy device\n");
> +		wiphy_free(wdev->wiphy);
> +		kfree(wdev);
> +		return NULL;
> +	}
>  
>  	priv->dev = net;
>  	return wdev;
> 


More information about the devel mailing list