From:   Eelco Chaudron <echaudro@redhat.com>
To:     Hangyu Hua <hbh25y@gmail.com>
Cc:     pshelar@ovn.org, davem@davemloft.net, edumazet@google.com,
        kuba@kernel.org, pabeni@redhat.com, xiangxia.m.yue@gmail.com,
        netdev@vger.kernel.org, dev@openvswitch.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] net: openvswitch: fix possible memory leak in
 ovs_meter_cmd_set()
Date:   Thu, 09 Feb 2023 09:26:59 +0100
Message-ID: <155E8FC1-746B-4BA4-BA80-60868B076F00@redhat.com>
In-Reply-To: <20230208071623.13013-1-hbh25y@gmail.com>
References: <20230208071623.13013-1-hbh25y@gmail.com>
MIME-Version: 1.0
Content-Type: text/plain
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Precedence: bulk


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 num=
ber")
> 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 =3D 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 glob=
al lock?

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

> 2.34.1