From: Cong Wang <[email protected]>
Date: Wed, 20 Dec 2017 23:26:24 -0800
> The rcu_barrier_bh() in mini_qdisc_pair_swap() is to wait for
> flying RCU callback installed by a previous mini_qdisc_pair_swap(),
> however we miss it on the tp_head==NULL path, which leads to that
> the RCU callback still uses miniq_old->rcu after it is freed together
> with qdisc in qdisc_graft(). So just add it on that path too.
>
> Fixes: 46209401f8f6 ("net: core: introduce mini_Qdisc and eliminate usage of
> tp->q for clsact fastpath ")
> Reported-by: Jakub Kicinski <[email protected]>
> Tested-by: Jakub Kicinski <[email protected]>
> Cc: Jiri Pirko <[email protected]>
> Cc: John Fastabend <[email protected]>
> Signed-off-by: Cong Wang <[email protected]>
Applied.
