Re: [PATCH net-next v4] net: ip6mr: add RTM_GETROUTE netlink op

From: David Ahern <dsahern@kernel.org>
To: David Lamparter <equinox@diac24.net>, netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Nikolay Aleksandrov <razor@blackwall.org>
Subject: Re: [PATCH net-next v4] net: ip6mr: add RTM_GETROUTE netlink op
Date: Wed, 6 Jul 2022 08:44:12 -0600	[thread overview]
Message-ID: <6c066fbb-0664-4a89-8c1e-7c369f6f894c@kernel.org> (raw)
In-Reply-To: <20220706100024.112074-1-equinox@diac24.net>

On 7/6/22 4:00 AM, David Lamparter wrote:
> diff --git a/net/ipv6/ip6mr.c b/net/ipv6/ip6mr.c
> index ec6e1509fc7c..f567c055dba4 100644
> --- a/net/ipv6/ip6mr.c
> +++ b/net/ipv6/ip6mr.c
> @@ -2510,6 +2512,104 @@ static void mrt6msg_netlink_event(const struct mr_table *mrt, struct sk_buff *pk
>  	rtnl_set_sk_err(net, RTNLGRP_IPV6_MROUTE_R, -ENOBUFS);
>  }
>  
> +static const struct nla_policy ip6mr_getroute_policy[RTA_MAX + 1] = {
> +	[RTA_SRC]		= NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
> +	[RTA_DST]		= NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
> +	[RTA_TABLE]		= { .type = NLA_U32 },
> +};
> +
> +static int ip6mr_rtm_valid_getroute_req(struct sk_buff *skb,
> +					const struct nlmsghdr *nlh,
> +					struct nlattr **tb,
> +					struct netlink_ext_ack *extack)
> +{
> +	struct rtmsg *rtm;
> +	int err;
> +
> +	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, ip6mr_getroute_policy,
> +			  extack);
> +	if (err)
> +		return err;
> +
> +	rtm = nlmsg_data(nlh);
> +	if ((rtm->rtm_src_len && rtm->rtm_src_len != 128) ||
> +	    (rtm->rtm_dst_len && rtm->rtm_dst_len != 128) ||
> +	    rtm->rtm_tos || rtm->rtm_table || rtm->rtm_protocol ||
> +	    rtm->rtm_scope || rtm->rtm_type || rtm->rtm_flags) {
> +		NL_SET_ERR_MSG(extack,
> +			       "ipv6: Invalid values in header for multicast route get request");

This (and other NL_SET_ERR_MSG) should be NL_SET_ERR_MSG_MOD and then
drop the "ipv6: " prefix on the messages; it comes from 'KBUILD_MODNAME
": "'

> +		return -EINVAL;
> +	}
> +
> +	if ((tb[RTA_SRC] && !rtm->rtm_src_len) ||
> +	    (tb[RTA_DST] && !rtm->rtm_dst_len)) {
> +		NL_SET_ERR_MSG(extack, "ipv6: rtm_src_len and rtm_dst_len must be 128 for IPv6");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +


with that change:
Reviewed-by: David Ahern <dsahern@kernel.org>