From: Du Cheng ducheng2@gmail.com
[ Upstream commit ed8157f1ebf1ae81a8fa2653e3f20d2076fad1c9 ]
There is a reproducible sequence from the userland that will trigger a WARN_ON() condition in taprio_get_start_time, which causes kernel to panic if configured as "panic_on_warn". Catch this condition in parse_taprio_schedule to prevent this condition.
Reported as bug on syzkaller: https://syzkaller.appspot.com/bug?extid=d50710fd0873a9c6b40c
Reported-by: syzbot+d50710fd0873a9c6b40c@syzkaller.appspotmail.com Signed-off-by: Du Cheng ducheng2@gmail.com Acked-by: Cong Wang cong.wang@bytedance.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/sched/sch_taprio.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 09116be99511..a4de4853c79d 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -900,6 +900,12 @@ static int parse_taprio_schedule(struct taprio_sched *q, struct nlattr **tb,
list_for_each_entry(entry, &new->entries, list) cycle = ktime_add_ns(cycle, entry->interval); + + if (!cycle) { + NL_SET_ERR_MSG(extack, "'cycle_time' can never be 0"); + return -EINVAL; + } + new->cycle_time = cycle; }