[PATCH 5.10 172/199] ipv6: create multicast route with RTPROT_KERNEL

From: Greg Kroah-Hartman
Date: Mon Jan 25 2021 - 14:23:53 EST


From: Matteo Croce <mcroce@xxxxxxxxxxxxx>

commit a826b04303a40d52439aa141035fca5654ccaccd upstream.

The ff00::/8 multicast route is created without specifying the fc_protocol
field, so the default RTPROT_BOOT value is used:

$ ip -6 -d route
unicast ::1 dev lo proto kernel scope global metric 256 pref medium
unicast fe80::/64 dev eth0 proto kernel scope global metric 256 pref medium
unicast ff00::/8 dev eth0 proto boot scope global metric 256 pref medium

As the documentation says, this value identifies routes installed during
boot, but the route is created when interface is set up.
Change the value to RTPROT_KERNEL which is a better value.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Matteo Croce <mcroce@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/ipv6/addrconf.c | 1 +
1 file changed, 1 insertion(+)

--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2468,6 +2468,7 @@ static void addrconf_add_mroute(struct n
.fc_flags = RTF_UP,
.fc_type = RTN_UNICAST,
.fc_nlinfo.nl_net = dev_net(dev),
+ .fc_protocol = RTPROT_KERNEL,
};

ipv6_addr_set(&cfg.fc_dst, htonl(0xFF000000), 0, 0, 0);