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From:   Eric Dumazet <edumazet@google.com>
Date:   Fri, 15 Sep 2023 16:40:17 +0200
Message-ID: <CANn89iJVM4J8DG4V3MdPcyimuKsbiko_vB=wYRyxnwzp_SiMTA@mail.gmail.com>
Subject: Re: [PATCH] net: sched: htb: dont intepret cls results when asked to drop
To:     Ma Ke <make_ruc2021@163.com>
Cc:     jhs@mojatatu.com, xiyou.wangcong@gmail.com, jiri@resnulli.us,
        davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
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On Fri, Sep 15, 2023 at 4:27=E2=80=AFPM Ma Ke <make_ruc2021@163.com> wrote:
>
> If asked to drop a packet via TC_ACT_SHOT it is unsafe to
> assume that res.class contains a valid pointer.
>
> Signed-off-by: Ma Ke <make_ruc2021@163.com>
> ---
>  net/sched/sch_htb.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
> index 0d947414e616..7b2e5037b713 100644
> --- a/net/sched/sch_htb.c
> +++ b/net/sched/sch_htb.c
> @@ -243,6 +243,8 @@ static struct htb_class *htb_classify(struct sk_buff =
*skb, struct Qdisc *sch,
>
>         *qerr =3D NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
>         while (tcf && (result =3D tcf_classify(skb, NULL, tcf, &res, fals=
e)) >=3D 0) {
> +               if (result =3D=3D TC_ACT_SHOT)
> +                       return NULL;
>  #ifdef CONFIG_NET_CLS_ACT
>                 switch (result) {
>                 case TC_ACT_QUEUED:
> @@ -250,8 +252,6 @@ static struct htb_class *htb_classify(struct sk_buff =
*skb, struct Qdisc *sch,
>                 case TC_ACT_TRAP:
>                         *qerr =3D NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
>                         fallthrough;
> -               case TC_ACT_SHOT:
> -                       return NULL;
>                 }
>  #endif
>                 cl =3D (void *)res.class;

Can you please stop sending patches that are not needed,
as already pointed out ?