From: Yunjian Wang <wangyunjian@huawei.com>
Date: Tue, 30 Mar 2021 14:27:48 +0000 (+0800)
Subject: sch_htb: fix null pointer dereference on a null new_q
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=ae81feb7338c89cee4e6aa0424bdab2ce2b52da2;p=linux.git

sch_htb: fix null pointer dereference on a null new_q

sch_htb: fix null pointer dereference on a null new_q

Currently if new_q is null, the null new_q pointer will be
dereference when 'q->offload' is true. Fix this by adding
a braces around htb_parent_to_leaf_offload() to avoid it.

Addresses-Coverity: ("Dereference after null check")
Fixes: d03b195b5aa0 ("sch_htb: Hierarchical QoS hardware offload")

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 62e12cb41a3e1..081c11d5717c4 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1675,9 +1675,10 @@ static int htb_delete(struct Qdisc *sch, unsigned long arg,
 					  cl->parent->common.classid,
 					  NULL);
 		if (q->offload) {
-			if (new_q)
+			if (new_q) {
 				htb_set_lockdep_class_child(new_q);
-			htb_parent_to_leaf_offload(sch, dev_queue, new_q);
+				htb_parent_to_leaf_offload(sch, dev_queue, new_q);
+			}
 		}
 	}