Re: [PATCH] net: sched: fix possible refcount leak in tc_new_tfilter()

From: Vlad Buslov
Date: Thu Sep 15 2022 - 10:21:13 EST


On Thu 15 Sep 2022 at 16:58, Hangyu Hua <hbh25y@xxxxxxxxx> wrote:
> tfilter_put need to be called to put the refount got by tp->ops->get to
> avoid possible refcount leak when chain->tmplt_ops == NULL or
> chain->tmplt_ops != tp->ops.
>
> Fixes: 7d5509fa0d3d ("net: sched: extend proto ops with 'put' callback")
> Signed-off-by: Hangyu Hua <hbh25y@xxxxxxxxx>
> ---

Thanks for fixing this!

Reviewed-by: Vlad Buslov <vladbu@xxxxxxxxxx>

> net/sched/cls_api.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
> index 790d6809be81..51d175f3fbcb 100644
> --- a/net/sched/cls_api.c
> +++ b/net/sched/cls_api.c
> @@ -2137,6 +2137,7 @@ static int tc_new_tfilter(struct sk_buff *skb, struct nlmsghdr *n,
> }
>
> if (chain->tmplt_ops && chain->tmplt_ops != tp->ops) {
> + tfilter_put(tp, fh);
> NL_SET_ERR_MSG(extack, "Chain template is set to a different filter kind");
> err = -EINVAL;
> goto errout;