Commit 4daf841a authored by Menglong Dong's avatar Menglong Dong Committed by David S. Miller
Browse files

net: ipv6: add skb drop reasons to ip6_rcv_core() 



Replace kfree_skb() used in ip6_rcv_core() with kfree_skb_reason().
No new drop reasons are added.

Seems now we use 'SKB_DROP_REASON_IP_INHDR' for too many case during
ipv6 header parse or check, just like what 'IPSTATS_MIB_INHDRERRORS'
do. Will it be too general and hard to know what happened?

Signed-off-by: default avatarMenglong Dong <imagedong@tencent.com>
Reviewed-by: default avatarJiang Biao <benbjiang@tencent.com>
Reviewed-by: default avatarHao Peng <flyingpeng@tencent.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 7d9dbdfb

net/ipv6/ip6_input.c

+16 −8
Original line number Diff line number Diff line
@@ -145,13 +145,14 @@ static void ip6_list_rcv_finish(struct net *net, struct sock *sk, 
static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev,

				    struct net *net)

{

	enum skb_drop_reason reason;

	const struct ipv6hdr *hdr;

	u32 pkt_len;

	struct inet6_dev *idev;



	if (skb->pkt_type == PACKET_OTHERHOST) {

		dev_core_stats_rx_otherhost_dropped_inc(skb->dev);

		kfree_skb(skb);

		kfree_skb_reason(skb, SKB_DROP_REASON_OTHERHOST);

		return NULL;

	}
@@ -161,9 +162,12 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, 


	__IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_IN, skb->len);



	SKB_DR_SET(reason, NOT_SPECIFIED);

	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL ||

	    !idev || unlikely(idev->cnf.disable_ipv6)) {

		__IP6_INC_STATS(net, idev, IPSTATS_MIB_INDISCARDS);

		if (unlikely(idev->cnf.disable_ipv6))

			SKB_DR_SET(reason, IPV6DISABLED);

		goto drop;

	}
@@ -187,8 +191,10 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, 


	hdr = ipv6_hdr(skb);



	if (hdr->version != 6)

	if (hdr->version != 6) {

		SKB_DR_SET(reason, UNHANDLED_PROTO);

		goto err;

	}



	__IP6_ADD_STATS(net, idev,

			IPSTATS_MIB_NOECTPKTS +
@@ -226,8 +232,10 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, 
	if (!ipv6_addr_is_multicast(&hdr->daddr) &&

	    (skb->pkt_type == PACKET_BROADCAST ||

	     skb->pkt_type == PACKET_MULTICAST) &&

	    idev->cnf.drop_unicast_in_l2_multicast)

	    idev->cnf.drop_unicast_in_l2_multicast) {

		SKB_DR_SET(reason, UNICAST_IN_L2_MULTICAST);

		goto err;

	}



	/* RFC4291 2.7

	 * Nodes must not originate a packet to a multicast address whose scope
@@ -256,12 +264,11 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, 
		if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {

			__IP6_INC_STATS(net,

					idev, IPSTATS_MIB_INTRUNCATEDPKTS);

			SKB_DR_SET(reason, PKT_TOO_SMALL);

			goto drop;

		}

		if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {

			__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);

			goto drop;

		}

		if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))

			goto err;

		hdr = ipv6_hdr(skb);

	}
@@ -282,9 +289,10 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev, 
	return skb;

err:

	__IP6_INC_STATS(net, idev, IPSTATS_MIB_INHDRERRORS);

	SKB_DR_OR(reason, IP_INHDR);

drop:

	rcu_read_unlock();

	kfree_skb(skb);

	kfree_skb_reason(skb, reason);

	return NULL;

}