From 57e595631904c827cfa1a0f7bbd7cc9a49da5745 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Mon, 23 Feb 2015 14:02:54 +0100 Subject: team: fix possible null pointer dereference in team_handle_frame Currently following race is possible in team: CPU0 CPU1 team_port_del team_upper_dev_unlink priv_flags &= ~IFF_TEAM_PORT team_handle_frame team_port_get_rcu team_port_exists priv_flags & IFF_TEAM_PORT == 0 return NULL (instead of port got from rx_handler_data) netdev_rx_handler_unregister The thing is that the flag is removed before rx_handler is unregistered. If team_handle_frame is called in between, team_port_exists returns 0 and team_port_get_rcu will return NULL. So do not check the flag here. It is guaranteed by netdev_rx_handler_unregister that team_handle_frame will always see valid rx_handler_data pointer. Signed-off-by: Jiri Pirko Fixes: 3d249d4ca7d0 ("net: introduce ethernet teaming device") Signed-off-by: David S. Miller --- drivers/net/team/team.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/net/team/team.c') diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 0e62274e884a..f1ee71e22241 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -43,9 +43,7 @@ static struct team_port *team_port_get_rcu(const struct net_device *dev) { - struct team_port *port = rcu_dereference(dev->rx_handler_data); - - return team_port_exists(dev) ? port : NULL; + return rcu_dereference(dev->rx_handler_data); } static struct team_port *team_port_get_rtnl(const struct net_device *dev) -- cgit v1.2.3 From 9215f437b85da339a7dfe3db6e288637406f88b2 Mon Sep 17 00:00:00 2001 From: Jiri Pirko Date: Wed, 4 Mar 2015 08:36:31 +0100 Subject: team: don't traverse port list using rcu in team_set_mac_address Currently the list is traversed using rcu variant. That is not correct since dev_set_mac_address can be called which eventually calls rtmsg_ifinfo_build_skb and there, skb allocation can sleep. So fix this by remove the rcu usage here. Fixes: 3d249d4ca7 "net: introduce ethernet teaming device" Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- drivers/net/team/team.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/net/team/team.c') diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index f1ee71e22241..7d394846afc2 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -1730,11 +1730,11 @@ static int team_set_mac_address(struct net_device *dev, void *p) if (dev->type == ARPHRD_ETHER && !is_valid_ether_addr(addr->sa_data)) return -EADDRNOTAVAIL; memcpy(dev->dev_addr, addr->sa_data, dev->addr_len); - rcu_read_lock(); - list_for_each_entry_rcu(port, &team->port_list, list) + mutex_lock(&team->lock); + list_for_each_entry(port, &team->port_list, list) if (team->ops.port_change_dev_addr) team->ops.port_change_dev_addr(team, port); - rcu_read_unlock(); + mutex_unlock(&team->lock); return 0; } -- cgit v1.2.3