Commit 33cba429 authored by Menglong Dong's avatar Menglong Dong Committed by David S. Miller
Browse files

net: ipv4: use kfree_skb_reason() in ip_rcv_core() 



Replace kfree_skb() with kfree_skb_reason() in ip_rcv_core(). Three new
drop reasons are introduced:

SKB_DROP_REASON_OTHERHOST
SKB_DROP_REASON_IP_CSUM
SKB_DROP_REASON_IP_INHDR

Signed-off-by: default avatarMenglong Dong <imagedong@tencent.com>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 2df3041b

include/linux/skbuff.h

+9 −0
Original line number Diff line number Diff line
@@ -321,6 +321,15 @@ enum skb_drop_reason { 
	SKB_DROP_REASON_SOCKET_FILTER,	/* dropped by socket filter */

	SKB_DROP_REASON_UDP_CSUM,	/* UDP checksum error */

	SKB_DROP_REASON_NETFILTER_DROP,	/* dropped by netfilter */

	SKB_DROP_REASON_OTHERHOST,	/* packet don't belong to current

					 * host (interface is in promisc

					 * mode)

					 */

	SKB_DROP_REASON_IP_CSUM,	/* IP checksum error */

	SKB_DROP_REASON_IP_INHDR,	/* there is something wrong with

					 * IP header (see

					 * IPSTATS_MIB_INHDRERRORS)

					 */

	SKB_DROP_REASON_MAX,

};

include/trace/events/skb.h

+3 −0
Original line number Diff line number Diff line
@@ -17,6 +17,9 @@ 
	EM(SKB_DROP_REASON_SOCKET_FILTER, SOCKET_FILTER)	\

	EM(SKB_DROP_REASON_UDP_CSUM, UDP_CSUM)			\

	EM(SKB_DROP_REASON_NETFILTER_DROP, NETFILTER_DROP)	\

	EM(SKB_DROP_REASON_OTHERHOST, OTHERHOST)		\

	EM(SKB_DROP_REASON_IP_CSUM, IP_CSUM)			\

	EM(SKB_DROP_REASON_IP_INHDR, IP_INHDR)			\

	EMe(SKB_DROP_REASON_MAX, MAX)



#undef EM

net/ipv4/ip_input.c

+10 −2
Original line number Diff line number Diff line
@@ -436,13 +436,16 @@ static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) 
static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net)

{

	const struct iphdr *iph;

	int drop_reason;

	u32 len;



	/* When the interface is in promisc. mode, drop all the crap

	 * that it receives, do not try to analyse it.

	 */

	if (skb->pkt_type == PACKET_OTHERHOST)

	if (skb->pkt_type == PACKET_OTHERHOST) {

		drop_reason = SKB_DROP_REASON_OTHERHOST;

		goto drop;

	}



	__IP_UPD_PO_STATS(net, IPSTATS_MIB_IN, skb->len);
@@ -452,6 +455,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) 
		goto out;

	}



	drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;

	if (!pskb_may_pull(skb, sizeof(struct iphdr)))

		goto inhdr_error;
@@ -488,6 +492,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) 


	len = ntohs(iph->tot_len);

	if (skb->len < len) {

		drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;

		__IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS);

		goto drop;

	} else if (len < (iph->ihl*4))
@@ -516,11 +521,14 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) 
	return skb;



csum_error:

	drop_reason = SKB_DROP_REASON_IP_CSUM;

	__IP_INC_STATS(net, IPSTATS_MIB_CSUMERRORS);

inhdr_error:

	if (drop_reason == SKB_DROP_REASON_NOT_SPECIFIED)

		drop_reason = SKB_DROP_REASON_IP_INHDR;

	__IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS);

drop:

	kfree_skb(skb);

	kfree_skb_reason(skb, drop_reason);

out:

	return NULL;

}