From: David Ahern Date: Wed, 7 Jun 2017 18:26:23 +0000 (-0600) Subject: net: ipv6: Release route when device is unregistering X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=8397ed36b7c585f8d3e06c431f4137309124f78f;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git net: ipv6: Release route when device is unregistering Roopa reported attempts to delete a bond device that is referenced in a multipath route is hanging: $ ifdown bond2 # ifupdown2 command that deletes virtual devices unregister_netdevice: waiting for bond2 to become free. Usage count = 2 Steps to reproduce: echo 1 > /proc/sys/net/ipv6/conf/all/ignore_routes_with_linkdown ip link add dev bond12 type bond ip link add dev bond13 type bond ip addr add 2001:db8:2::0/64 dev bond12 ip addr add 2001:db8:3::0/64 dev bond13 ip route add 2001:db8:33::0/64 nexthop via 2001:db8:2::2 nexthop via 2001:db8:3::2 ip link del dev bond12 ip link del dev bond13 The root cause is the recent change to keep routes on a linkdown. Update the check to detect when the device is unregistering and release the route for that case. Fixes: a1a22c12060e4 ("net: ipv6: Keep nexthop of multipath route on admin down") Reported-by: Roopa Prabhu Signed-off-by: David Ahern Acked-by: Roopa Prabhu Signed-off-by: David S. Miller --- diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ab7ca3fdc495..846193dfb0ac 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4262,6 +4262,11 @@ static inline const char *netdev_name(const struct net_device *dev) return dev->name; } +static inline bool netdev_unregistering(const struct net_device *dev) +{ + return dev->reg_state == NETREG_UNREGISTERING; +} + static inline const char *netdev_reg_state(const struct net_device *dev) { switch (dev->reg_state) { diff --git a/net/ipv6/route.c b/net/ipv6/route.c index dc61b0b5e64e..7cebd954d5bb 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2804,6 +2804,7 @@ static int fib6_ifdown(struct rt6_info *rt, void *arg) if ((rt->dst.dev == dev || !dev) && rt != adn->net->ipv6.ip6_null_entry && (rt->rt6i_nsiblings == 0 || + (dev && netdev_unregistering(dev)) || !rt->rt6i_idev->cnf.ignore_routes_with_linkdown)) return -1;