From 925b0c841e066b488cc3a60272472b2c56300704 Mon Sep 17 00:00:00 2001 From: Hangbin Liu Date: Fri, 19 Apr 2019 14:31:00 +0800 Subject: [PATCH] team: fix possible recursive locking when add slaves If we add a bond device which is already the master of the team interface, we will hold the team->lock in team_add_slave() first and then request the lock in team_set_mac_address() again. The functions are called like: - team_add_slave() - team_port_add() - team_port_enter() - team_modeop_port_enter() - __set_port_dev_addr() - dev_set_mac_address() - bond_set_mac_address() - dev_set_mac_address() - team_set_mac_address Although team_upper_dev_link() would check the upper devices but it is called too late. Fix it by adding a checking before processing the slave. v2: Do not split the string in netdev_err() Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device") Acked-by: Jiri Pirko Signed-off-by: Hangbin Liu Signed-off-by: David S. Miller --- drivers/net/team/team.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 9ce61b019aad..16963f7a88f7 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -1156,6 +1156,13 @@ static int team_port_add(struct team *team, struct net_device *port_dev, return -EINVAL; } + if (netdev_has_upper_dev(dev, port_dev)) { + NL_SET_ERR_MSG(extack, "Device is already an upper device of the team interface"); + netdev_err(dev, "Device %s is already an upper device of the team interface\n", + portname); + return -EBUSY; + } + if (port_dev->features & NETIF_F_VLAN_CHALLENGED && vlan_uses_dev(dev)) { NL_SET_ERR_MSG(extack, "Device is VLAN challenged and team device has VLAN set up");