netdev - [PATCH] net: sched: fix potential null pointer deref

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220610021445.2441579-1-jianhao_xu@smail.nju.edu.cn>
Date:   Fri, 10 Jun 2022 04:14:45 +0200
From:   Jianhao Xu <jianhao_xu@...il.nju.edu.cn>
To:     jhs@...atatu.com, xiyou.wangcong@...il.com, jiri@...nulli.us,
        davem@...emloft.net, edumazet@...gle.com, kuba@...nel.org,
        pabeni@...hat.com
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jianhao Xu <jianhao_xu@...il.nju.edu.cn>
Subject: [PATCH] net: sched: fix potential null pointer deref

mq_queue_get() may return NULL, a check is needed to avoid using
the NULL pointer.

Signed-off-by: Jianhao Xu <jianhao_xu@...il.nju.edu.cn>
---
 net/sched/sch_mq.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/sched/sch_mq.c b/net/sched/sch_mq.c
index 83d2e54bf303..9aca4ca82947 100644
--- a/net/sched/sch_mq.c
+++ b/net/sched/sch_mq.c
@@ -201,6 +201,8 @@ static int mq_graft(struct Qdisc *sch, unsigned long cl, struct Qdisc *new,
 static struct Qdisc *mq_leaf(struct Qdisc *sch, unsigned long cl)
 {
 	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+	if (!dev_queue)
+		return NULL;
 
 	return dev_queue->qdisc_sleeping;
 }
@@ -218,6 +220,8 @@ static int mq_dump_class(struct Qdisc *sch, unsigned long cl,
 			 struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+	if (!dev_queue)
+		return -1;
 
 	tcm->tcm_parent = TC_H_ROOT;
 	tcm->tcm_handle |= TC_H_MIN(cl);
@@ -229,6 +233,8 @@ static int mq_dump_class_stats(struct Qdisc *sch, unsigned long cl,
 			       struct gnet_dump *d)
 {
 	struct netdev_queue *dev_queue = mq_queue_get(sch, cl);
+	if (!dev_queue)
+		return -1;
 
 	sch = dev_queue->qdisc_sleeping;
 	if (gnet_stats_copy_basic(d, sch->cpu_bstats, &sch->bstats, true) < 0 ||
-- 
2.25.1