[SKBUFF]: Fix up csum_start when head room changes

Thanks for noticing the bug where csum_start is not updated
when the head room changes.

This patch fixes that.  It also moves the csum/ip_summed
copying into copy_skb_header so that skb_copy_expand gets
it too.  I've checked its callers and no one should be upset
by this.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu 2007-09-16 16:32:11 -07:00 committed by David S. Miller
parent 0cfad07555
commit 52886051ff

View File

@ -472,6 +472,9 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
#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;
@ -545,8 +548,6 @@ struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t gfp_mask)
skb_reserve(n, headerlen);
/* Set the tail pointer and length */
skb_put(n, skb->len);
n->csum = skb->csum;
n->ip_summed = skb->ip_summed;
if (skb_copy_bits(skb, -headerlen, n->head, headerlen + skb->len))
BUG();
@ -589,8 +590,6 @@ struct sk_buff *pskb_copy(struct sk_buff *skb, gfp_t gfp_mask)
skb_put(n, skb_headlen(skb));
/* Copy the bytes */
skb_copy_from_linear_data(skb, n->data, n->len);
n->csum = skb->csum;
n->ip_summed = skb->ip_summed;
n->truesize += skb->data_len;
n->data_len = skb->data_len;
@ -686,6 +685,7 @@ int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail,
skb->transport_header += off;
skb->network_header += off;
skb->mac_header += off;
skb->csum_start += off;
skb->cloned = 0;
skb->hdr_len = 0;
skb->nohdr = 0;
@ -734,9 +734,6 @@ struct sk_buff *skb_realloc_headroom(struct sk_buff *skb, unsigned int headroom)
*
* You must pass %GFP_ATOMIC as the allocation priority if this function
* is called from an interrupt.
*
* BUG ALERT: ip_summed is not copied. Why does this work? Is it used
* only by netfilter in the cases when checksum is recalculated? --ANK
*/
struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
int newheadroom, int newtailroom,
@ -749,7 +746,7 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
gfp_mask);
int oldheadroom = skb_headroom(skb);
int head_copy_len, head_copy_off;
int off = 0;
int off;
if (!n)
return NULL;
@ -773,12 +770,13 @@ struct sk_buff *skb_copy_expand(const struct sk_buff *skb,
copy_skb_header(n, skb);
#ifdef NET_SKBUFF_DATA_USES_OFFSET
off = newheadroom - oldheadroom;
#endif
n->csum_start += off;
#ifdef NET_SKBUFF_DATA_USES_OFFSET
n->transport_header += off;
n->network_header += off;
n->mac_header += off;
#endif
return n;
}