netdev - Re: [PATCH net-next,v2 2/2] net: sched: add em_ipt ematch for calling xtables matches

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 26 Jan 2018 19:50:19 +0100
From:   Pablo Neira Ayuso <pablo@...filter.org>
To:     Eyal Birger <eyal.birger@...il.com>
Cc:     davem@...emloft.net, jhs@...atatu.com, xiyou.wangcong@...il.com,
        netdev@...r.kernel.org, shmulik@...anetworks.com,
        Eyal Birger <eyal@...anetworks.com>
Subject: Re: [PATCH net-next,v2 2/2] net: sched: add em_ipt ematch for
 calling xtables matches

On Fri, Jan 26, 2018 at 06:48:53PM +0200, Eyal Birger wrote:
> diff --git a/net/sched/em_ipt.c b/net/sched/em_ipt.c
> new file mode 100644
> index 0000000..2103b30
> --- /dev/null
> +++ b/net/sched/em_ipt.c
[...]
> +static int em_ipt_match(struct sk_buff *skb, struct tcf_ematch *em,
> +			struct tcf_pkt_info *info)
> +{
> +	const struct em_ipt_match *im = (const void *)em->data;
> +	struct xt_action_param acpar = {};
> +	struct net_device *indev = NULL;
> +	struct nf_hook_state state;
> +	int ret;
> +
> +	if (unlikely(!skb_at_tc_ingress(skb))) {
> +		pr_notice_once("ipt match must not be used at egress\n");

Isn't there a way to reject the use of this from ->change()? ie. from
control plane configuration.

> +		return 0;
> +	}