Subject: Re: [PATCH] ethtool: check the ethtool_ops is NULL in dev_ethtool

From: Daniel Borkmann <[email-masked]>
Date: Mon, 17 Feb 2014 18:09:58 +0100

On 02/17/2014 12:31 PM, Wang Weidong wrote:
> some drivers maybe not implement the ethtool_ops with only
> set NULL. So when call the ethtool cmds will lead to a
> 'NULL pointer dereference'.
>
> So add a checking in dev_ethtool.
>
> Signed-off-by: Wang Weidong <[email-masked]>
> ---
>   net/core/ethtool.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/net/core/ethtool.c b/net/core/ethtool.c
> index 30071de..f418dcb 100644
> --- a/net/core/ethtool.c
> +++ b/net/core/ethtool.c
> @@ -1499,6 +1499,9 @@ int dev_ethtool(struct net *net, struct ifreq *ifr)
>   		if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
>   			return -EPERM;
>   	}
> +	

You have a trailing whitespace/tab in the line above. Please
use checkpatch for detecting such things.

Can you be more specific with "some drivers"? Any driver that
is in the mainline tree?

> +	if (!dev->ethtool_ops)
> +		return -EOPNOTSUPP;
>
>   	if (dev->ethtool_ops->begin) {
>   		rc = dev->ethtool_ops->begin(dev);
>