From a2d3f3e33853ef52e5f66b41c3e8ee5710aa3305 Mon Sep 17 00:00:00 2001 From: Matteo Croce Date: Thu, 5 Oct 2017 19:03:05 +0200 Subject: [PATCH] ipv6: fix net.ipv6.conf.all.accept_dad behaviour for real Commit 35e015e1f577 ("ipv6: fix net.ipv6.conf.all interface DAD handlers") was intended to affect accept_dad flag handling in such a way that DAD operation and mode on a given interface would be selected according to the maximum value of conf/{all,interface}/accept_dad. However, addrconf_dad_begin() checks for particular cases in which we need to skip DAD, and this check was modified in the wrong way. Namely, it was modified so that, if the accept_dad flag is 0 for the given interface *or* for all interfaces, DAD would be skipped. We have instead to skip DAD if accept_dad is 0 for the given interface *and* for all interfaces. Fixes: 35e015e1f577 ("ipv6: fix net.ipv6.conf.all interface DAD handlers") Acked-by: Stefano Brivio Signed-off-by: Matteo Croce Reported-by: Erik Kline Signed-off-by: David S. Miller --- net/ipv6/addrconf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 96861c702c06..4a96ebbf8eda 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -3820,8 +3820,8 @@ static void addrconf_dad_begin(struct inet6_ifaddr *ifp) goto out; if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) || - dev_net(dev)->ipv6.devconf_all->accept_dad < 1 || - idev->cnf.accept_dad < 1 || + (dev_net(dev)->ipv6.devconf_all->accept_dad < 1 && + idev->cnf.accept_dad < 1) || !(ifp->flags&IFA_F_TENTATIVE) || ifp->flags & IFA_F_NODAD) { bump_id = ifp->flags & IFA_F_TENTATIVE; -- 2.20.1