releases/5.0.10/bonding-fix-event-handling-for-stacked-bonds.patch

   1 From foo@baz Sat Apr 20 16:43:09 CEST 2019
   2 From: Sabrina Dubroca <sd@queasysnail.net>
   3 Date: Fri, 12 Apr 2019 15:04:10 +0200
   4 Subject: bonding: fix event handling for stacked bonds
   5
   6 From: Sabrina Dubroca <sd@queasysnail.net>
   7
   8 [ Upstream commit 92480b3977fd3884649d404cbbaf839b70035699 ]
   9
  10 When a bond is enslaved to another bond, bond_netdev_event() only
  11 handles the event as if the bond is a master, and skips treating the
  12 bond as a slave.
  13
  14 This leads to a refcount leak on the slave, since we don't remove the
  15 adjacency to its master and the master holds a reference on the slave.
  16
  17 Reproducer:
  18   ip link add bondL type bond
  19   ip link add bondU type bond
  20   ip link set bondL master bondU
  21   ip link del bondL
  22
  23 No "Fixes:" tag, this code is older than git history.
  24
  25 Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
  26 Signed-off-by: David S. Miller <davem@davemloft.net>
  27 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  28 ---
  29  drivers/net/bonding/bond_main.c |    6 +++++-
  30  1 file changed, 5 insertions(+), 1 deletion(-)
  31
  32 --- a/drivers/net/bonding/bond_main.c
  33 +++ b/drivers/net/bonding/bond_main.c
  34 @@ -3214,8 +3214,12 @@ static int bond_netdev_event(struct noti
  35                 return NOTIFY_DONE;
  36
  37         if (event_dev->flags & IFF_MASTER) {
  38 +               int ret;
  39 +
  40                 netdev_dbg(event_dev, "IFF_MASTER\n");
  41 -               return bond_master_netdev_event(event, event_dev);
  42 +               ret = bond_master_netdev_event(event, event_dev);
  43 +               if (ret != NOTIFY_DONE)
  44 +                       return ret;
  45         }
  46
  47         if (event_dev->flags & IFF_SLAVE) {