net/ipv6: re-do dad when interface has IFF_NOARP flag change
When we add a new IPv6 address, we should also join corresponding solicited-node multicast address, unless the interface has IFF_NOARP flag, as function addrconf_join_solict() did. But if we remove IFF_NOARP flag later, we do not do dad and add the mcast address. So we will drop corresponding neighbour discovery message that came from other nodes. A typical example is after creating a ipvlan with mode l3, setting up an ipv6 address and changing the mode to l2. Then we will not be able to ping this address as the interface doesn't join related solicited-node mcast address. Fix it by re-doing dad when interface changed IFF_NOARP flag. Then we will add corresponding mcast group and check if there is a duplicate address on the network. Reported-by: NJianlin Shi <jishi@redhat.com> Reviewed-by: NStefano Brivio <sbrivio@redhat.com> Signed-off-by: NHangbin Liu <liuhangbin@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Showing
想要评论请 注册 或 登录