4.14-stable review patch. If anyone has any objections, please let me know.
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From: David Ahern dsahern@gmail.com
[ Upstream commit 98d11291d189cb5adf49694d0ad1b971c0212697 ]
Florian reported a breakage with anycast routes due to commit 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address"). Prior to this commit anycast routes were added against the loopback device causing repetitive route entries with no insight into why they existed. e.g.: $ ip -6 ro ls table local type anycast anycast 2001:db8:1:: dev lo proto kernel metric 0 pref medium anycast 2001:db8:2:: dev lo proto kernel metric 0 pref medium anycast fe80:: dev lo proto kernel metric 0 pref medium anycast fe80:: dev lo proto kernel metric 0 pref medium
The point of commit 4832c30d5458 is to add the routes using the device with the address which is causing the route to be added. e.g.,: $ ip -6 ro ls table local type anycast anycast 2001:db8:1:: dev eth1 proto kernel metric 0 pref medium anycast 2001:db8:2:: dev eth2 proto kernel metric 0 pref medium anycast fe80:: dev eth2 proto kernel metric 0 pref medium anycast fe80:: dev eth1 proto kernel metric 0 pref medium
For traffic to work as it did before, the dst device needs to be switched to the loopback when the copy is created similar to local routes.
Fixes: 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") Signed-off-by: David Ahern dsahern@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/ipv6/route.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -960,7 +960,7 @@ static struct net_device *ip6_rt_get_dev { struct net_device *dev = rt->dst.dev;
- if (rt->rt6i_flags & RTF_LOCAL) { + if (rt->rt6i_flags & (RTF_LOCAL | RTF_ANYCAST)) { /* for copies of local routes, dst->dev needs to be the * device if it is a master device, the master device if * device is enslaved, and the loopback as the default