From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jiri Pirko <jiri@resnulli.us>
Subject: Re: [PATCH net 1/4] net/sched: act_gact: disallow 'goto chain' on
 fallback control action
Date: Mon, 22 Oct 2018 22:55:54 +0200
Message-ID: <20181022205554.GA2556@nanopsycho.orion>
References: <cover.1540070509.git.dcaratti@redhat.com>
 <02f04ade8a0087781778d02fbb645b1d72f9d777.1540070509.git.dcaratti@redhat.com>
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Cc: Cong Wang <xiyou.wangcong@gmail.com>,
        Jamal Hadi Salim <jhs@mojatatu.com>,
        "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org
To: Davide Caratti <dcaratti@redhat.com>
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Sat, Oct 20, 2018 at 11:33:07PM CEST, dcaratti@redhat.com wrote:
>in the following command:
>
> # tc action add action <c1> random <rand_type> <c2> <rand_param>
>
>'goto chain x' is allowed only for c1: setting it for c2 makes the kernel
>crash with NULL pointer dereference, since TC core doesn't initialize the
>chain handle.
>
>Signed-off-by: Davide Caratti <dcaratti@redhat.com>
>---
> net/sched/act_gact.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
>diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
>index cd1d9bd32ef9..505138047e5c 100644
>--- a/net/sched/act_gact.c
>+++ b/net/sched/act_gact.c
>@@ -88,6 +88,11 @@ static int tcf_gact_init(struct net *net, struct nlattr *nla,
> 		p_parm = nla_data(tb[TCA_GACT_PROB]);
> 		if (p_parm->ptype >= MAX_RAND)
> 			return -EINVAL;
>+		if (TC_ACT_EXT_CMP(p_parm->paction, TC_ACT_GOTO_CHAIN)) {
>+			NL_SET_ERR_MSG(extack,
>+				       "goto chain not allowed on fallback");

No need for a line-wrap. Otherwise
Acked-by: Jiri Pirko <jiri@mellanox.com>