3.16.50-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
commit 3bdac362a2f89ed3e148fa6f38c5f5d858f50b1a upstream.
Depending on where ->init fails we can get a null pointer deref due to
uninitialized hires timer (watchdog) or a double free of the qdisc hash
because it is already freed by ->destroy().
Fixes: 8d5537387505 ("net/sched/hfsc: allocate tcf block for hfsc root class")
Fixes: 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation")
Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
[bwh: Backported to 3.16: sch_hfsc doesn't use a tcf block]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1432,6 +1432,8 @@ hfsc_init_qdisc(struct Qdisc *sch, struc
struct tc_hfsc_qopt *qopt;
int err;
+ qdisc_watchdog_init(&q->watchdog, sch);
+
if (opt == NULL || nla_len(opt) < sizeof(*qopt))
return -EINVAL;
qopt = nla_data(opt);
@@ -1457,8 +1459,6 @@ hfsc_init_qdisc(struct Qdisc *sch, struc
qdisc_class_hash_insert(&q->clhash, &q->root.cl_common);
qdisc_class_hash_grow(sch, &q->clhash);
- qdisc_watchdog_init(&q->watchdog, sch);
-
return 0;
}