Re: [PATCH net-next] ethtool: fix null-ptr-deref on ref tracker

[Eric Dumazet <eric.dumazet@gmail.com>]

On 12/13/21 5:39 PM, Jakub Kicinski wrote:
> dev can be a NULL here, not all requests set require_dev.
>
> Fixes: e4b8954074f6 ("netlink: add net device refcount tracker to struct ethnl_req_info")
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>   net/ethtool/netlink.c | 6 ++++--
>   1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
> index 23f32a995099..767fb3f17267 100644
> --- a/net/ethtool/netlink.c
> +++ b/net/ethtool/netlink.c
> @@ -141,8 +141,10 @@ int ethnl_parse_header_dev_get(struct ethnl_req_info *req_info,
>   		return -EINVAL;
>   	}
>   


Oh I am reading your patch after I sent mine.


Please use edumazet@google.com next time, because eric.dumazet@gmail.com has

huge lag (typical vger -> accounts@gmail.com issues)


Reviewed-by: Eric Dumazet <edumazet@google.com>


Thanks !




> -	req_info->dev = dev;
> -	netdev_tracker_alloc(dev, &req_info->dev_tracker, GFP_KERNEL);
> +	if (dev) {
> +		req_info->dev = dev;
> +		netdev_tracker_alloc(dev, &req_info->dev_tracker, GFP_KERNEL);
> +	}
>   	req_info->flags = flags;
>   	return 0;
>   }