[PATCH 4.4 17/97] net: ipv6: send unsolicited NA on admin up

From: Greg Kroah-Hartman
Date: Fri Mar 23 2018 - 06:53:36 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: David Ahern <dsa@xxxxxxxxxxxxxxxxxxx>


[ Upstream commit 4a6e3c5def13c91adf2acc613837001f09af3baa ]

ndisc_notify is the ipv6 equivalent to arp_notify. When arp_notify is
set to 1, gratuitous arp requests are sent when the device is brought up.
The same is expected when ndisc_notify is set to 1 (per ndisc_notify in
Documentation/networking/ip-sysctl.txt). The NA is not sent on NETDEV_UP
event; add it.

Fixes: 5cb04436eef6 ("ipv6: add knob to send unsolicited ND on link-layer address change")
Signed-off-by: David Ahern <dsa@xxxxxxxxxxxxxxxxxxx>
Acked-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/ndisc.c | 2 ++
1 file changed, 2 insertions(+)

--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -1686,6 +1686,8 @@ static int ndisc_netdev_event(struct not
case NETDEV_CHANGEADDR:
neigh_changeaddr(&nd_tbl, dev);
fib6_run_gc(0, net, false);
+ /* fallthrough */
+ case NETDEV_UP:
idev = in6_dev_get(dev);
if (!idev)
break;