@@ -52,14 +52,6 @@
static const char nf_frags_cache_name[] = "nf-frags";
-struct nf_ct_frag6_skb_cb
-{
- struct inet6_skb_parm h;
- int offset;
-};
-
-#define NFCT_FRAG6_CB(skb) ((struct nf_ct_frag6_skb_cb *)((skb)->cb))
-
static struct inet_frags nf_frags;
#ifdef CONFIG_SYSCTL
@@ -270,13 +262,13 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
* this fragment, right?
*/
prev = fq->q.fragments_tail;
- if (!prev || NFCT_FRAG6_CB(prev)->offset < offset) {
+ if (!prev || prev->ip_defrag_offset < offset) {
next = NULL;
goto found;
}
prev = NULL;
for (next = fq->q.fragments; next != NULL; next = next->next) {
- if (NFCT_FRAG6_CB(next)->offset >= offset)
+ if (next->ip_defrag_offset >= offset)
break; /* bingo! */
prev = next;
}
@@ -292,14 +284,19 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
/* Check for overlap with preceding fragment. */
if (prev &&
- (NFCT_FRAG6_CB(prev)->offset + prev->len) > offset)
+ (prev->ip_defrag_offset + prev->len) > offset)
goto discard_fq;
/* Look for overlap with succeeding segment. */
- if (next && NFCT_FRAG6_CB(next)->offset < end)
+ if (next && next->ip_defrag_offset < end)
goto discard_fq;
- NFCT_FRAG6_CB(skb)->offset = offset;
+ /* Note : skb->ip_defrag_offset and skb->dev share the same location */
+ if (skb->dev)
+ fq->iif = skb->dev->ifindex;
+ /* Makes sure compiler wont do silly aliasing games */
+ barrier();
+ skb->ip_defrag_offset = offset;
/* Insert this fragment in the chain of fragments. */
skb->next = next;
@@ -310,10 +307,6 @@ static int nf_ct_frag6_queue(struct frag_queue *fq, struct sk_buff *skb,
else
fq->q.fragments = skb;
- if (skb->dev) {
- fq->iif = skb->dev->ifindex;
- skb->dev = NULL;
- }
fq->q.stamp = skb->tstamp;
fq->q.meat += skb->len;
fq->ecn |= ecn;
@@ -357,7 +350,7 @@ nf_ct_frag6_reasm(struct frag_queue *fq, struct sk_buff *prev, struct net_devic
inet_frag_kill(&fq->q);
WARN_ON(head == NULL);
- WARN_ON(NFCT_FRAG6_CB(head)->offset != 0);
+ WARN_ON(head->ip_defrag_offset != 0);
ecn = ip_frag_ecn_table[fq->ecn];
if (unlikely(ecn == 0xff))
nf_ct_frag6_queue() uses skb->cb[] to store the fragment offset, meaning that we could use two cache lines per skb when finding the insertion point, if for some reason inet6_skb_parm size is increased in the future. By using skb->ip_defrag_offset instead of skb->cb[] we pack all the fields in a single cache line, matching what we did for IPv4. Signed-off-by: Eric Dumazet <edumazet@google.com> --- net/ipv6/netfilter/nf_conntrack_reasm.c | 29 ++++++++++--------------- 1 file changed, 11 insertions(+), 18 deletions(-)