Re: [RFC PATCH net-next] ipv6: Queue fragments per interface for multicast/link-local addresses.

[Eric Dumazet <eric.dumazet@gmail.com>]

On Sat, 2013-02-16 at 14:03 +0900, YOSHIFUJI Hideaki wrote:
> We should queue fragments for the same link-local address on
> different interfaces (e.g. fe80::1%eth0 and fe80::1%eth1) to the
> different queue, because of nature of addressing architecture.
> 
> Similarly, we should queue fragments for multicast on different
> interface to the different queue.  This is okay because
> application joins group on speicific interface, and multicast
> traffic is expected only on that interface.
> 
> CC: Ben Greear <greearb@candelatech.com>
> CC: Vlad Yasevich <vyasevic@redhat.com>
> CC: Eric Dumazet <eric.dumazet@gmail.com>
> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
> ---
>  include/net/ipv6.h    |    1 +
>  net/ipv6/reassembly.c |   11 +++++++++--
>  2 files changed, 10 insertions(+), 2 deletions(-)
> 
> diff --git a/include/net/ipv6.h b/include/net/ipv6.h
> index 851d541..1af98aa 100644
> --- a/include/net/ipv6.h
> +++ b/include/net/ipv6.h
> @@ -463,6 +463,7 @@ enum ip6_defrag_users {
>  struct ip6_create_arg {
>  	__be32 id;
>  	u32 user;
> +	int ifindex;
>  	const struct in6_addr *src;
>  	const struct in6_addr *dst;
>  };
> diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
> index bab2c27..83f02f5 100644
> --- a/net/ipv6/reassembly.c
> +++ b/net/ipv6/reassembly.c
> @@ -113,6 +113,7 @@ bool ip6_frag_match(struct inet_frag_queue *q, void *a)
>  
>  	fq = container_of(q, struct frag_queue, q);
>  	return	fq->id == arg->id &&
> +		(!arg->ifindex || fq->iif == arg->ifindex) &&
>  		fq->user == arg->user &&
>  		ipv6_addr_equal(&fq->saddr, arg->src) &&
>  		ipv6_addr_equal(&fq->daddr, arg->dst);
> @@ -182,13 +183,18 @@ static void ip6_frag_expire(unsigned long data)
>  }
>  
>  static __inline__ struct frag_queue *
> -fq_find(struct net *net, __be32 id, const struct in6_addr *src, const struct in6_addr *dst)
> +fq_find(struct net *net, __be32 id, int ifindex, const struct in6_addr *src, const struct in6_addr *dst)
>  {
>  	struct inet_frag_queue *q;
>  	struct ip6_create_arg arg;
>  	unsigned int hash;
> +	int addr_type = ipv6_addr_type(dst);
>  
>  	arg.id = id;
> +	if (addr_type & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LINKLOCAL))
> +		arg.ifindex = ifindex;
> +	else
> +		arg.ifindex = 0;
>  	arg.user = IP6_DEFRAG_LOCAL_DELIVER;
>  	arg.src = src;
>  	arg.dst = dst;
> @@ -534,7 +540,8 @@ static int ipv6_frag_rcv(struct sk_buff *skb)
>  		IP6_ADD_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
>  				 IPSTATS_MIB_REASMFAILS, evicted);
>  
> -	fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr);
> +	fq = fq_find(net, fhdr->identification, skb->dev->ifindex,
> +		     &hdr->saddr, &hdr->daddr);
>  	if (fq != NULL) {
>  		int ret;
>  


Hmm... This breaks net/ipv6/netfilter/nf_conntrack_reasm.c