Commit dec18810 authored by Herbert Xu's avatar Herbert Xu Committed by David S. Miller
Browse files

[SKBUFF]: Merge common code between copy_skb_header and skb_clone 



This patch creates a new function __copy_skb_header to merge the common
code between copy_skb_header and skb_clone.  Having two functions which
are largely the same is a source of wasted labour as well as confusion.

In fact the tc_verd stuff is almost certainly a bug since it's treated
differently in skb_clone compared to the callers of copy_skb_header
(skb_copy/pskb_copy/skb_copy_expand).

I've kept that difference in tact with a comment added asking for
clarification.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f4921aff

net/core/skbuff.c

+45 −71
Original line number Diff line number Diff line
@@ -362,6 +362,44 @@ void kfree_skb(struct sk_buff *skb) 
	__kfree_skb(skb);

}



static void __copy_skb_header(struct sk_buff *new, const struct sk_buff *old)

{

	new->tstamp		= old->tstamp;

	new->dev		= old->dev;

	new->transport_header	= old->transport_header;

	new->network_header	= old->network_header;

	new->mac_header		= old->mac_header;

	new->dst		= dst_clone(old->dst);

#ifdef CONFIG_INET

	new->sp			= secpath_get(old->sp);

#endif

	memcpy(new->cb, old->cb, sizeof(old->cb));

	new->csum_start		= old->csum_start;

	new->csum_offset	= old->csum_offset;

	new->local_df		= old->local_df;

	new->pkt_type		= old->pkt_type;

	new->ip_summed		= old->ip_summed;

	skb_copy_queue_mapping(new, old);

	new->priority		= old->priority;

#if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)

	new->ipvs_property	= old->ipvs_property;

#endif

	new->protocol		= old->protocol;

	new->mark		= old->mark;

	__nf_copy(new, old);

#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \

    defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)

	new->nf_trace		= old->nf_trace;

#endif

#ifdef CONFIG_NET_SCHED

	new->tc_index		= old->tc_index;

#ifdef CONFIG_NET_CLS_ACT

	new->tc_verd		= old->tc_verd;

#endif

#endif

	skb_copy_secmark(new, old);

}



/**

 *	skb_clone	-	duplicate an sk_buff

 *	@skb: buffer to clone
@@ -397,51 +435,22 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask) 


	n->next = n->prev = NULL;

	n->sk = NULL;

	C(tstamp);

	C(dev);

	C(transport_header);

	C(network_header);

	C(mac_header);

	C(dst);

	dst_clone(skb->dst);

	C(sp);

#ifdef CONFIG_INET

	secpath_get(skb->sp);

#endif

	memcpy(n->cb, skb->cb, sizeof(skb->cb));

	__copy_skb_header(n, skb);



	C(len);

	C(data_len);

	C(mac_len);

	C(csum);

	C(local_df);

	n->cloned = 1;

	n->hdr_len = skb->nohdr ? skb_headroom(skb) : skb->hdr_len;

	n->nohdr = 0;

	C(pkt_type);

	C(ip_summed);

	skb_copy_queue_mapping(n, skb);

	C(priority);

#if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)

	C(ipvs_property);

#endif

	C(protocol);

	n->destructor = NULL;

	C(mark);

	__nf_copy(n, skb);

#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \

    defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)

	C(nf_trace);

#endif

#ifdef CONFIG_NET_SCHED

	C(tc_index);

#ifdef CONFIG_NET_CLS_ACT

	n->tc_verd = SET_TC_VERD(skb->tc_verd,0);

	/* FIXME What is this and why don't we do it in copy_skb_header? */

	n->tc_verd = SET_TC_VERD(n->tc_verd,0);

	n->tc_verd = CLR_TC_OK2MUNGE(n->tc_verd);

	n->tc_verd = CLR_TC_MUNGED(n->tc_verd);

	C(iif);

#endif

#endif

	skb_copy_secmark(n, skb);

	C(truesize);

	atomic_set(&n->users, 1);

	C(head);
@@ -463,50 +472,15 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old) 
	 */

	unsigned long offset = new->data - old->data;

#endif

	new->sk		= NULL;

	new->dev	= old->dev;

	skb_copy_queue_mapping(new, old);

	new->priority	= old->priority;

	new->protocol	= old->protocol;

	new->dst	= dst_clone(old->dst);

#ifdef CONFIG_INET

	new->sp		= secpath_get(old->sp);

#endif

	new->csum_start = old->csum_start;

	new->csum_offset = old->csum_offset;

	new->ip_summed = old->ip_summed;

	new->transport_header = old->transport_header;

	new->network_header   = old->network_header;

	new->mac_header	      = old->mac_header;



	__copy_skb_header(new, old);



#ifndef NET_SKBUFF_DATA_USES_OFFSET

	/* {transport,network,mac}_header are relative to skb->head */

	new->transport_header += offset;

	new->network_header   += offset;

	new->mac_header	      += offset;

#endif

	memcpy(new->cb, old->cb, sizeof(old->cb));

	new->local_df	= old->local_df;

	new->fclone	= SKB_FCLONE_UNAVAILABLE;

	new->pkt_type	= old->pkt_type;

	new->tstamp	= old->tstamp;

	new->destructor = NULL;

	new->mark	= old->mark;

	__nf_copy(new, old);

#if defined(CONFIG_NETFILTER_XT_TARGET_TRACE) || \

    defined(CONFIG_NETFILTER_XT_TARGET_TRACE_MODULE)

	new->nf_trace	= old->nf_trace;

#endif

#if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)

	new->ipvs_property = old->ipvs_property;

#endif

#ifdef CONFIG_NET_SCHED

#ifdef CONFIG_NET_CLS_ACT

	new->tc_verd = old->tc_verd;

#endif

	new->tc_index	= old->tc_index;

#endif

	skb_copy_secmark(new, old);

	atomic_set(&new->users, 1);

	skb_shinfo(new)->gso_size = skb_shinfo(old)->gso_size;

	skb_shinfo(new)->gso_segs = skb_shinfo(old)->gso_segs;

	skb_shinfo(new)->gso_type = skb_shinfo(old)->gso_type;