Commit 4ecbb1c2 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

net: dropreason: add SKB_DROP_REASON_DUP_FRAG 



This is used to track when a duplicate segment received by various
reassembly units is dropped.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 511a3eda

include/net/dropreason.h

+3 −0
Original line number Diff line number Diff line
@@ -68,6 +68,7 @@ 
	FN(IP_INADDRERRORS)		\

	FN(IP_INNOROUTES)		\

	FN(PKT_TOO_BIG)			\

	FN(DUP_FRAG)			\

	FNe(MAX)



/**
@@ -300,6 +301,8 @@ enum skb_drop_reason { 
	 * MTU)

	 */

	SKB_DROP_REASON_PKT_TOO_BIG,

	/** @SKB_DROP_REASON_DUP_FRAG: duplicate fragment */

	SKB_DROP_REASON_DUP_FRAG,

	/**

	 * @SKB_DROP_REASON_MAX: the maximum of drop reason, which shouldn't be

	 * used as a real 'reason'

net/ipv4/ip_fragment.c

+9 −4
Original line number Diff line number Diff line
@@ -278,10 +278,14 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 
	struct net_device *dev;

	unsigned int fragsize;

	int err = -ENOENT;

	SKB_DR(reason);

	u8 ecn;



	if (qp->q.flags & INET_FRAG_COMPLETE)

	/* If reassembly is already done, @skb must be a duplicate frag. */

	if (qp->q.flags & INET_FRAG_COMPLETE) {

		SKB_DR_SET(reason, DUP_FRAG);

		goto err;

	}



	if (!(IPCB(skb)->flags & IPSKB_FRAG_COMPLETE) &&

	    unlikely(ip_frag_too_far(qp)) &&
@@ -382,8 +386,9 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 


insert_error:

	if (err == IPFRAG_DUP) {

		kfree_skb(skb);

		return -EINVAL;

		SKB_DR_SET(reason, DUP_FRAG);

		err = -EINVAL;

		goto err;

	}

	err = -EINVAL;

	__IP_INC_STATS(net, IPSTATS_MIB_REASM_OVERLAPS);
@@ -391,7 +396,7 @@ static int ip_frag_queue(struct ipq *qp, struct sk_buff *skb) 
	inet_frag_kill(&qp->q);

	__IP_INC_STATS(net, IPSTATS_MIB_REASMFAILS);

err:

	kfree_skb(skb);

	kfree_skb_reason(skb, reason);

	return err;

}

net/ipv6/netfilter/nf_conntrack_reasm.c

+1 −1
Original line number Diff line number Diff line
@@ -253,7 +253,7 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb, 
	if (err) {

		if (err == IPFRAG_DUP) {

			/* No error for duplicates, pretend they got queued. */

			kfree_skb(skb);

			kfree_skb_reason(skb, SKB_DROP_REASON_DUP_FRAG);

			return -EINPROGRESS;

		}

		goto insert_error;

net/ipv6/reassembly.c

+9 −4
Original line number Diff line number Diff line
@@ -112,10 +112,14 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
	struct sk_buff *prev_tail;

	struct net_device *dev;

	int err = -ENOENT;

	SKB_DR(reason);

	u8 ecn;



	if (fq->q.flags & INET_FRAG_COMPLETE)

	/* If reassembly is already done, @skb must be a duplicate frag. */

	if (fq->q.flags & INET_FRAG_COMPLETE) {

		SKB_DR_SET(reason, DUP_FRAG);

		goto err;

	}



	err = -EINVAL;

	offset = ntohs(fhdr->frag_off) & ~0x7;
@@ -226,8 +230,9 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 


insert_error:

	if (err == IPFRAG_DUP) {

		kfree_skb(skb);

		return -EINVAL;

		SKB_DR_SET(reason, DUP_FRAG);

		err = -EINVAL;

		goto err;

	}

	err = -EINVAL;

	__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
@@ -237,7 +242,7 @@ static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
	__IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),

			IPSTATS_MIB_REASMFAILS);

err:

	kfree_skb(skb);

	kfree_skb_reason(skb, reason);

	return err;

}