From 4f823defdd5b106a5e89745ee8b163c71855de1e Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Fri, 30 Oct 2015 10:23:33 +0200 Subject: [PATCH] ipv4: fix to not remove local route on link down When fib_netdev_event calls fib_disable_ip on NETDEV_DOWN event we should not delete the local routes if the local address is still present. The confusion comes from the fact that both fib_netdev_event and fib_inetaddr_event use the NETDEV_DOWN constant. Fix it by returning back the variable 'force'. Steps to reproduce: modprobe dummy ifconfig dummy0 192.168.168.1 up ifconfig dummy0 down ip route list table local | grep dummy | grep host local 192.168.168.1 dev dummy0 proto kernel scope host src 192.168.168.1 Fixes: 8a3d03166f19 ("net: track link-status of ipv4 nexthops") Signed-off-by: Julian Anastasov Signed-off-by: David S. Miller --- include/net/ip_fib.h | 2 +- net/ipv4/fib_frontend.c | 13 +++++++------ net/ipv4/fib_semantics.c | 11 ++++++++--- 3 files changed, 16 insertions(+), 10 deletions(-) diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h index 727d6e9a9685..965fa5b1a274 100644 --- a/include/net/ip_fib.h +++ b/include/net/ip_fib.h @@ -317,7 +317,7 @@ void fib_flush_external(struct net *net); /* Exported by fib_semantics.c */ int ip_fib_check_default(__be32 gw, struct net_device *dev); -int fib_sync_down_dev(struct net_device *dev, unsigned long event); +int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force); int fib_sync_down_addr(struct net *net, __be32 local); int fib_sync_up(struct net_device *dev, unsigned int nh_flags); void fib_select_multipath(struct fib_result *res); diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 690bcbc59f26..457b2cd75b85 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1110,9 +1110,10 @@ static void nl_fib_lookup_exit(struct net *net) net->ipv4.fibnl = NULL; } -static void fib_disable_ip(struct net_device *dev, unsigned long event) +static void fib_disable_ip(struct net_device *dev, unsigned long event, + bool force) { - if (fib_sync_down_dev(dev, event)) + if (fib_sync_down_dev(dev, event, force)) fib_flush(dev_net(dev)); rt_cache_flush(dev_net(dev)); arp_ifdown(dev); @@ -1140,7 +1141,7 @@ static int fib_inetaddr_event(struct notifier_block *this, unsigned long event, /* Last address was deleted from this interface. * Disable IP. */ - fib_disable_ip(dev, event); + fib_disable_ip(dev, event, true); } else { rt_cache_flush(dev_net(dev)); } @@ -1157,7 +1158,7 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo unsigned int flags; if (event == NETDEV_UNREGISTER) { - fib_disable_ip(dev, event); + fib_disable_ip(dev, event, true); rt_flush_dev(dev); return NOTIFY_DONE; } @@ -1178,14 +1179,14 @@ static int fib_netdev_event(struct notifier_block *this, unsigned long event, vo rt_cache_flush(net); break; case NETDEV_DOWN: - fib_disable_ip(dev, event); + fib_disable_ip(dev, event, false); break; case NETDEV_CHANGE: flags = dev_get_flags(dev); if (flags & (IFF_RUNNING | IFF_LOWER_UP)) fib_sync_up(dev, RTNH_F_LINKDOWN); else - fib_sync_down_dev(dev, event); + fib_sync_down_dev(dev, event, false); /* fall through */ case NETDEV_CHANGEMTU: rt_cache_flush(net); diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 064bd3caaa4f..2aa5b5e7da75 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -1281,7 +1281,13 @@ int fib_sync_down_addr(struct net *net, __be32 local) return ret; } -int fib_sync_down_dev(struct net_device *dev, unsigned long event) +/* Event force Flags Description + * NETDEV_CHANGE 0 LINKDOWN Carrier OFF, not for scope host + * NETDEV_DOWN 0 LINKDOWN|DEAD Link down, not for scope host + * NETDEV_DOWN 1 LINKDOWN|DEAD Last address removed + * NETDEV_UNREGISTER 1 LINKDOWN|DEAD Device removed + */ +int fib_sync_down_dev(struct net_device *dev, unsigned long event, bool force) { int ret = 0; int scope = RT_SCOPE_NOWHERE; @@ -1290,8 +1296,7 @@ int fib_sync_down_dev(struct net_device *dev, unsigned long event) struct hlist_head *head = &fib_info_devhash[hash]; struct fib_nh *nh; - if (event == NETDEV_UNREGISTER || - event == NETDEV_DOWN) + if (force) scope = -1; hlist_for_each_entry(nh, head, nh_hash) { -- 2.20.1