sch_hhf: ensure quantum and hhf_non_hh_weight are non-zero
authorCong Wang <xiyou.wangcong@gmail.com>
Sun, 8 Sep 2019 20:40:51 +0000 (13:40 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 19 Sep 2019 07:09:31 +0000 (09:09 +0200)
commita9e91767b921ee196ab693fa13a81b278f53ddac
treef475fbff199341310551e87af793af0cbacced71
parenta7f46e18ecfe7e169e9f5f6e4afeceb26527769a
sch_hhf: ensure quantum and hhf_non_hh_weight are non-zero

[ Upstream commit d4d6ec6dac07f263f06d847d6f732d6855522845 ]

In case of TCA_HHF_NON_HH_WEIGHT or TCA_HHF_QUANTUM is zero,
it would make no progress inside the loop in hhf_dequeue() thus
kernel would get stuck.

Fix this by checking this corner case in hhf_change().

Fixes: 10239edf86f1 ("net-qdisc-hhf: Heavy-Hitter Filter (HHF) qdisc")
Reported-by: syzbot+bc6297c11f19ee807dc2@syzkaller.appspotmail.com
Reported-by: syzbot+041483004a7f45f1f20a@syzkaller.appspotmail.com
Reported-by: syzbot+55be5f513bed37fc4367@syzkaller.appspotmail.com
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Terry Lam <vtlam@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net/sched/sch_hhf.c