netdev - [PATCH net] ipv6: set all.accept

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Date:   Mon, 13 Nov 2017 14:45:36 +0100
From:   Nicolas Dichtel <nicolas.dichtel@...nd.com>
To:     davem@...emloft.net
Cc:     netdev@...r.kernel.org,
        Nicolas Dichtel <nicolas.dichtel@...nd.com>,
        Stefano Brivio <sbrivio@...hat.com>,
        Matteo Croce <mcroce@...hat.com>, Erik Kline <ek@...gle.com>
Subject: [PATCH net] ipv6: set all.accept_dad to 0 by default

The commit a2d3f3e33853 modifies the way to disable dad on an interface.
Before the patch, setting <iface>.accept_dad to 0 was enough to disable it.
Because all.accept_dad is set to 1 by default, after the patch, the user
needs to set both all.accept_dad and <iface>.accept_dad to 0 to disable it.

This is not backward compatible. When a user updates its kernel, the dad
may be enabled by error.

Let's set all.accept_dad to 0 by default to restore the previous behavior.

Fixes: a2d3f3e33853 ("ipv6: fix net.ipv6.conf.all.accept_dad behaviour for real")
CC: Stefano Brivio <sbrivio@...hat.com>
CC: Matteo Croce <mcroce@...hat.com>
CC: Erik Kline <ek@...gle.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@...nd.com>
---
 net/ipv6/addrconf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 8a1c846d3df9..ef5b61507b9a 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -231,7 +231,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
 	.proxy_ndp		= 0,
 	.accept_source_route	= 0,	/* we do not accept RH0 by default. */
 	.disable_ipv6		= 0,
-	.accept_dad		= 1,
+	.accept_dad		= 0,
 	.suppress_frag_ndisc	= 1,
 	.accept_ra_mtu		= 1,
 	.stable_secret		= {
-- 
2.13.2