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Date:   Thu, 18 Jun 2020 07:54:56 -0700 (PDT)
Message-Id: <20200618.075456.550840877226409223.davem@davemloft.net>
To:     gaurav1086@gmail.com
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        kuba@kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] [net/sched] Fix null pointer deref skb in tc_ctl_action
From:   David Miller <davem@davemloft.net>
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From: Gaurav Singh <gaurav1086@gmail.com>
Date: Wed, 17 Jun 2020 21:43:28 -0400

> Add null check for skb
> 
> Signed-off-by: Gaurav Singh <gaurav1086@gmail.com>
> ---
>  net/sched/act_api.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/net/sched/act_api.c b/net/sched/act_api.c
> index 8ac7eb0a8309..fd584821d75a 100644
> --- a/net/sched/act_api.c
> +++ b/net/sched/act_api.c
> @@ -1473,9 +1473,12 @@ static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
>  static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
>  			 struct netlink_ext_ack *extack)
>  {
> +	if (!skb)
> +		return 0;
> +
>  	struct net *net = sock_net(skb->sk);

You're adding code before variable declarations, this is not correct.

I find your work to be very rushed and sloppy, please take your time
and submit well formed and tested changes.

Thank you.