[PATCH 3.16 082/192] ipv6: always add flag an address that failed DAD with DADFAILED

From: Ben Hutchings
Date: Mon Oct 09 2017 - 08:57:06 EST


3.16.49-rc1 review patch. If anyone has any objections, please let me know.

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

From: Lubomir Rintel <lkundrak@xxxxx>

commit 3d171f3907329d4b1ce31d5ec9c852c5f0269578 upstream.

The userspace needs to know why is the address being removed so that it can
perhaps obtain a new address.

Without the DADFAILED flag it's impossible to distinguish removal of a
temporary and tentative address due to DAD failure from other reasons (device
removed, manual address removal).

Signed-off-by: Lubomir Rintel <lkundrak@xxxxx>
Acked-by: Hannes Frederic Sowa <hannes@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
net/ipv6/addrconf.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1610,12 +1610,13 @@ struct inet6_ifaddr *ipv6_get_ifaddr(str

static void addrconf_dad_stop(struct inet6_ifaddr *ifp, int dad_failed)
{
+ if (dad_failed)
+ ifp->flags |= IFA_F_DADFAILED;
+
if (ifp->flags&IFA_F_PERMANENT) {
spin_lock_bh(&ifp->lock);
addrconf_del_dad_work(ifp);
ifp->flags |= IFA_F_TENTATIVE;
- if (dad_failed)
- ifp->flags |= IFA_F_DADFAILED;
spin_unlock_bh(&ifp->lock);
if (dad_failed)
ipv6_ifa_notify(0, ifp);