Since taprio’s taprio_dev_notifier() isn’t protected by an
RCU read-side critical section, a race with advance_sched()
can lead to a use-after-free.
Adding rcu_read_lock() inside taprio_dev_notifier() prevents this.
Fixes: fed87cc6718a ("net/sched: taprio: automatically calculate queueMaxSDU based on TC gate durations")
Cc: stable@vger.kernel.org
Signed-off-by: Hyunwoo Kim <imv4bel@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/aEzIYYxt0is9upYG@v4bel-B760M-AORUS-ELITE-AX
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
stab = rtnl_dereference(q->root->stab);
- oper = rtnl_dereference(q->oper_sched);
+ rcu_read_lock();
+ oper = rcu_dereference(q->oper_sched);
if (oper)
taprio_update_queue_max_sdu(q, oper, stab);
- admin = rtnl_dereference(q->admin_sched);
+ admin = rcu_dereference(q->admin_sched);
if (admin)
taprio_update_queue_max_sdu(q, admin, stab);
+ rcu_read_unlock();
break;
}