ipv6: don't count addrconf generated routes against gc limit

[ Upstream commit a3300ef4bbb1f1e33ff0400e1e6cf7733d988f4f ]

Brett Ciphery reported that new ipv6 addresses failed to get installed
because the addrconf generated dsts where counted against the dst gc
limit. We don't need to count those routes like we currently don't count
administratively added routes.

Because the max_addresses check enforces a limit on unbounded address
generation first in case someone plays with router advertisments, we
are still safe here.

Reported-by: Brett Ciphery <brett.ciphery@windriver.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 5 deletions

diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index 8a8ae819c1d8..566c1b4b21b8 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -2099,12 +2099,10 @@ struct rt6_info *addrconf_dst_alloc(struct inet6_dev *idev,
                                     bool anycast)
 {
         struct net *net = dev_net(idev->dev);
-        struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev, 0, NULL);
-
-        if (!rt) {
-                net_warn_ratelimited("Maximum number of routes reached, consider increasing route/max_size\n");
+        struct rt6_info *rt = ip6_dst_alloc(net, net->loopback_dev,
+                                            DST_NOCOUNT, NULL);
+        if (!rt)
                 return ERR_PTR(-ENOMEM);
-        }
 
         in6_dev_hold(idev);