tree 14335495cf00e966fa425b467395b6b38dd77a57
parent a8801799c6975601fd58ae62f48964caec2eb83f
author WANG Cong <xiyou.wangcong@gmail.com> 1491357090 -0700
committer David S. Miller <davem@davemloft.net> 1491506919 -0700

net_sched: check noop_qdisc before qdisc_hash_add()

Dmitry reported a crash when injecting faults in
attach_one_default_qdisc() and dev->qdisc is still
a noop_disc, the check before qdisc_hash_add() fails
to catch it because it tests NULL. We should test
against noop_qdisc since it is the default qdisc
at this point.

Fixes: 59cc1f61f09c ("net: sched: convert qdisc linked list to hashtable")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>