| Message ID | 1446193414-8244-3-git-send-email-ja@ssi.bg |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 2aa5b5e..e966f85 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1445,6 +1445,13 @@ int fib_sync_up(struct net_device *dev, unsigned int nh_flags) if (!(dev->flags & IFF_UP)) return 0; + if (nh_flags & RTNH_F_DEAD) { + unsigned int flags = dev_get_flags(dev); + + if (flags & (IFF_RUNNING | IFF_LOWER_UP)) + nh_flags |= RTNH_F_LINKDOWN; + } + prev_fi = NULL; hash = fib_devindex_hashfn(dev->ifindex); head = &fib_info_devhash[hash];
When nexthop is part of multipath route we should clear the LINKDOWN flag when link goes UP or when first address is added. This is needed because we always set LINKDOWN flag when DEAD flag was set but now on UP the nexthop is not dead anymore. Examples when LINKDOWN bit can be forgotten when no NETDEV_CHANGE is delivered: - link goes down (LINKDOWN is set), then link goes UP and device shows carrier OK but LINKDOWN remains set - last address is deleted (LINKDOWN is set), then address is added and device shows carrier OK but LINKDOWN remains set Steps to reproduce: modprobe dummy ifconfig dummy0 192.168.168.1 up here add a multipath route where one nexthop is for dummy0: ip route add 1.2.3.4 nexthop dummy0 nexthop SOME_OTHER_DEVICE ifconfig dummy0 down ifconfig dummy0 up now ip route shows nexthop that is not dead. Now set the sysctl var: echo 1 > /proc/sys/net/ipv4/conf/dummy0/ignore_routes_with_linkdown now ip route will show a dead nexthop because the forgotten RTNH_F_LINKDOWN is propagated as RTNH_F_DEAD. Fixes: 8a3d03166f19 ("net: track link-status of ipv4 nexthops") Signed-off-by: Julian Anastasov <ja@ssi.bg> --- net/ipv4/fib_semantics.c | 7 +++++++ 1 file changed, 7 insertions(+)