net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)

There is a subtle change in behaviour introduced by:
  commit c7a1ce397a
  'ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create'

Before that patch /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo

Afterwards /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80240001 lo

ie. the above commit causes the ::1/128 local (automatic) route to be flagged with RTF_ADDRCONF (0x040000).

AFAICT, this is incorrect since these routes are *not* coming from RA's.

As such, this patch restores the old behaviour.

Fixes: c7a1ce397a ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create")
Cc: David Ahern <dsahern@gmail.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Maciej Żenczykowski 2019-09-02 09:23:36 -07:00 committed by David S. Miller
parent 10eb56c582
commit d55a2e374a

View File

@ -4388,13 +4388,14 @@ struct fib6_info *addrconf_f6i_alloc(struct net *net,
struct fib6_config cfg = {
.fc_table = l3mdev_fib_table(idev->dev) ? : RT6_TABLE_LOCAL,
.fc_ifindex = idev->dev->ifindex,
.fc_flags = RTF_UP | RTF_ADDRCONF | RTF_NONEXTHOP,
.fc_flags = RTF_UP | RTF_NONEXTHOP,
.fc_dst = *addr,
.fc_dst_len = 128,
.fc_protocol = RTPROT_KERNEL,
.fc_nlinfo.nl_net = net,
.fc_ignore_dev_down = true,
};
struct fib6_info *f6i;
if (anycast) {
cfg.fc_type = RTN_ANYCAST;
@ -4404,7 +4405,10 @@ struct fib6_info *addrconf_f6i_alloc(struct net *net,
cfg.fc_flags |= RTF_LOCAL;
}
return ip6_route_info_create(&cfg, gfp_flags, NULL);
f6i = ip6_route_info_create(&cfg, gfp_flags, NULL);
if (f6i)
f6i->dst_nocount = true;
return f6i;
}
/* remove deleted ip from prefsrc entries */