Re: [PATCH] net: openvswitch: fix possible memory leak in ovs_meter_cmd_set()

[Eelco Chaudron <echaudro@redhat.com>]

On 8 Feb 2023, at 8:16, Hangyu Hua wrote:

> old_meter needs to be free after it is detached regardless of whether
> the new meter is successfully attached.
>
> Fixes: c7c4c44c9a95 ("net: openvswitch: expand the meters supported number")
> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
> ---
>  net/openvswitch/meter.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/net/openvswitch/meter.c b/net/openvswitch/meter.c
> index 6e38f68f88c2..e84082e209e9 100644
> --- a/net/openvswitch/meter.c
> +++ b/net/openvswitch/meter.c
> @@ -448,8 +448,10 @@ static int ovs_meter_cmd_set(struct sk_buff *skb, struct genl_info *info)
>  		goto exit_unlock;
>
>  	err = attach_meter(meter_tbl, meter);
> -	if (err)
> +	if (err) {
> +		ovs_meter_free(old_meter);
>  		goto exit_unlock;

It would be nicer to add another goto label like exit_free_old_meter.

+	if (err)
+     	goto exit_free_old_meter:

exit_free_old_meter:
    ovs_meter_free(old_meter);
exit_unlock:
	ovs_unlock();
	nlmsg_free(reply);
exit_free_meter:


Or maybe it would be even nicer to free the old_meter outside of the global lock?

> +	}
>
>  	ovs_unlock();
>
> -- 
> 2.34.1