The bond_ipsec_* helpers don't need RTNL, and can potentially get called without it being held, so switch from rtnl_dereference() to rcu_dereference() to access bond struct data.
Lightly tested with xfrm bonding, no problems found, should address the syzkaller bug referenced below. Reported-by: [email protected] CC: Huy Nguyen <[email protected]> CC: Saeed Mahameed <[email protected]> CC: Jay Vosburgh <[email protected]> CC: Veaceslav Falico <[email protected]> CC: Andy Gospodarek <[email protected]> CC: "David S. Miller" <[email protected]> CC: Jeff Kirsher <[email protected]> CC: Jakub Kicinski <[email protected]> CC: Steffen Klassert <[email protected]> CC: Herbert Xu <[email protected]> CC: [email protected] CC: [email protected] Signed-off-by: Jarod Wilson <[email protected]> --- drivers/net/bonding/bond_main.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index f886d97c4359..e2d491c4378c 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -390,7 +390,7 @@ static int bond_ipsec_add_sa(struct xfrm_state *xs) return -EINVAL; bond = netdev_priv(bond_dev); - slave = rtnl_dereference(bond->curr_active_slave); + slave = rcu_dereference(bond->curr_active_slave); xs->xso.real_dev = slave->dev; bond->xs = xs; @@ -417,7 +417,7 @@ static void bond_ipsec_del_sa(struct xfrm_state *xs) return; bond = netdev_priv(bond_dev); - slave = rtnl_dereference(bond->curr_active_slave); + slave = rcu_dereference(bond->curr_active_slave); if (!slave) return; @@ -442,7 +442,7 @@ static bool bond_ipsec_offload_ok(struct sk_buff *skb, struct xfrm_state *xs) { struct net_device *bond_dev = xs->xso.dev; struct bonding *bond = netdev_priv(bond_dev); - struct slave *curr_active = rtnl_dereference(bond->curr_active_slave); + struct slave *curr_active = rcu_dereference(bond->curr_active_slave); struct net_device *slave_dev = curr_active->dev; if (BOND_MODE(bond) != BOND_MODE_ACTIVEBACKUP) -- 2.20.1
