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

From: Eelco Chaudron
Date: Thu Feb 09 2023 - 03:27:57 EST




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@xxxxxxxxx>
> ---
> 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