ipv6: avoid dad-failures for addresses with NODAD
authorMahesh Bandewar <maheshb@google.com>
Sat, 13 May 2017 00:03:39 +0000 (17:03 -0700)
committerDavid S. Miller <davem@davemloft.net>
Mon, 15 May 2017 18:31:51 +0000 (14:31 -0400)
commit66eb9f86e50547ec2a8ff7a75997066a74ef584b
tree46c8efe4f0cb340ba36156f4f1590c20c11f0894
parentaa4ad88cfcd4ee45f527fb982140576711e3b501
ipv6: avoid dad-failures for addresses with NODAD

Every address gets added with TENTATIVE flag even for the addresses with
IFA_F_NODAD flag and dad-work is scheduled for them. During this DAD process
we realize it's an address with NODAD and complete the process without
sending any probe. However the TENTATIVE flags stays on the
address for sometime enough to cause misinterpretation when we receive a NS.
While processing NS, if the address has TENTATIVE flag, we mark it DADFAILED
and endup with an address that was originally configured as NODAD with
DADFAILED.

We can't avoid scheduling dad_work for addresses with NODAD but we can
avoid adding TENTATIVE flag to avoid this racy situation.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/ipv6/addrconf.c