3.2.95-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 3.2: 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 @@ -1435,6 +1435,8 @@ 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); @@ -1460,8 +1462,6 @@ 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; }