rtnl/bond: don't send rtnl msg for unregistered iface

[ Upstream commit ed2a80ab7b76f11af0b2c6255709c4ebf164b667 ]

Before the patch, the command 'ip link add bond2 type bond mode 802.3ad'
causes the kernel to send a rtnl message for the bond2 interface, with an
ifindex 0.

'ip monitor' shows:
0: bond2: <BROADCAST,MULTICAST,MASTER> mtu 1500 state DOWN group default
    link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
9: bond2@NONE: <BROADCAST,MULTICAST,MASTER> mtu 1500 qdisc noop state DOWN group default
    link/ether ea:3e:1f:53:92:7b brd ff:ff:ff:ff:ff:ff
[snip]

The patch fixes the spotted bug by checking in bond driver if the interface
is registered before calling the notifier chain.
It also adds a check in rtmsg_ifinfo() to prevent this kind of bug in the
future.

Fixes: d4261e565000 ("bonding: create netlink event when bonding option is changed")
CC: Jiri Pirko <jiri@resnulli.us>
Reported-by: Julien Meunier <julien.meunier@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>

diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c
index b62697f4a3deb90a5c2209ad6f032c6984284510..f1c53944a2c30798da2af12de8bd4cab616d50da 100644 (file)
--- a/drivers/net/bonding/bond_options.c
+++ b/drivers/net/bonding/bond_options.c
@@ -625,7 +625,7 @@ int __bond_opt_set(struct bonding *bond,
 out:
        if (ret)
                bond_opt_error_interpret(bond, opt, ret, val);
-       else
+       else if (bond->dev->reg_state == NETREG_REGISTERED)
                call_netdevice_notifiers(NETDEV_CHANGEINFODATA, bond->dev);
 
        return ret;

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index c522f7a00eab1435605f9ab09571a5643062bada..24d3242f0e018f12e3bd7dbf0c8b16bb266864eb 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2229,6 +2229,9 @@ void rtmsg_ifinfo(int type, struct net_device *dev, unsigned int change,
        int err = -ENOBUFS;
        size_t if_info_size;
 
+       if (dev->reg_state != NETREG_REGISTERED)
+               return;
+
        skb = nlmsg_new((if_info_size = if_nlmsg_size(dev, 0)), flags);
        if (skb == NULL)
                goto errout;