path: root/net/ipv4/fib_semantics.c
diff options
authorIdo Schimmel <idosch@mellanox.com>2017-07-28 23:27:44 +0300
committerDavid S. Miller <davem@davemloft.net>2017-07-31 17:51:11 -0700
commit71ed7ee35ad2c5300f4b51634185a0193b4fb0fa (patch)
tree2d4154df8757c876a60c261357cf8ba1a85a9aa6 /net/ipv4/fib_semantics.c
parentnet: phy: Correctly process PHY_HALTED in phy_stop_machine() (diff)
ipv4: fib: Fix NULL pointer deref during fib_sync_down_dev()
Michał reported a NULL pointer deref during fib_sync_down_dev() when unregistering a netdevice. The problem is that we don't check for 'in_dev' being NULL, which can happen in very specific cases. Usually routes are flushed upon NETDEV_DOWN sent in either the netdev or the inetaddr notification chains. However, if an interface isn't configured with any IP address, then it's possible for host routes to be flushed following NETDEV_UNREGISTER, after NULLing dev->ip_ptr in inetdev_destroy(). To reproduce: $ ip link add type dummy $ ip route add local dev dummy0 $ ip link del dev dummy0 Fix this by checking for the presence of 'in_dev' before referencing it. Fixes: 982acb97560c ("ipv4: fib: Notify about nexthop status changes") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reported-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Tested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/fib_semantics.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index 222100103808..b8d18171cca3 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -1452,7 +1452,7 @@ static int call_fib_nh_notifiers(struct fib_nh *fib_nh,
return call_fib_notifiers(dev_net(fib_nh->nh_dev), event_type,
+ if ((in_dev && IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) &&
fib_nh->nh_flags & RTNH_F_LINKDOWN) ||
(fib_nh->nh_flags & RTNH_F_DEAD))
return call_fib_notifiers(dev_net(fib_nh->nh_dev),