ipv6: resend MLD report if a link-local address completes DAD

RFC3590/RFC3810 specifies we should resend MLD reports as soon as a
valid link-local address is available.

We now use the valid_ll_addr_cnt to check if it is necessary to resend
a new report.

Changes since Flavio Leitner's version:
a) adapt for valid_ll_addr_cnt
b) resend first reports directly in the path and just arm the timer for
   mc_qrv-1 resends.

Reported-by: Flavio Leitner <fleitner@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Stevens <dlstevens@us.ibm.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Flavio Leitner <fbl@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 3 insertions, 0 deletions

diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 21f702704f24..f68eaf574d7e 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -155,6 +155,7 @@ extern bool ipv6_chk_mcast_addr(struct net_device *dev,
                                 const struct in6_addr *group,
                                 const struct in6_addr *src_addr);
 
+extern void ipv6_mc_dad_complete(struct inet6_dev *idev);
 /*
  * identify MLD packets for MLD filter exceptions
  */
diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h
index 1628b8f5fb26..736b5fb95474 100644
--- a/include/net/if_inet6.h
+++ b/include/net/if_inet6.h
@@ -174,10 +174,12 @@ struct inet6_dev {
         unsigned char           mc_qrv;
         unsigned char           mc_gq_running;
         unsigned char           mc_ifc_count;
+        unsigned char           mc_dad_count;
         unsigned long           mc_v1_seen;
         unsigned long           mc_maxdelay;
         struct timer_list       mc_gq_timer;    /* general query timer */
         struct timer_list       mc_ifc_timer;   /* interface change timer */
+        struct timer_list       mc_dad_timer;   /* dad complete mc timer */
 
         struct ifacaddr6        *ac_list;
         rwlock_t                lock;