net: bridge: start hello timer only if device is up

When the transition of NO_STP -> KERNEL_STP was fixed by always calling
mod_timer in br_stp_start, it introduced a new regression which causes
the timer to be armed even when the bridge is down, and since we stop
the timers in its ndo_stop() function, they never get disabled if the
device is destroyed before it's upped.

To reproduce:
$ while :; do ip l add br0 type bridge hello_time 100; brctl stp br0 on;
ip l del br0; done;

CC: Xin Long <lucien.xin@gmail.com>
CC: Ivan Vecera <cera@cera.cz>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reported-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Fixes: 6d18c732b9 ("bridge: start hello_timer when enabling KERNEL_STP in br_stp_start")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Nikolay Aleksandrov 2017-06-01 18:07:55 +03:00 committed by David S. Miller
parent 3968d38917
commit aeb073241f

View file

@ -179,7 +179,8 @@ static void br_stp_start(struct net_bridge *br)
br_debug(br, "using kernel STP\n");
/* To start timers on any ports left in blocking */
mod_timer(&br->hello_timer, jiffies + br->hello_time);
if (br->dev->flags & IFF_UP)
mod_timer(&br->hello_timer, jiffies + br->hello_time);
br_port_state_selection(br);
}