From: Eric Dumazet <edumazet@google.com>
Date: Sun, 3 May 2020 03:09:25 +0000 (-0700)
Subject: net_sched: sch_skbprio: add message validation to skbprio_change()
X-Git-Tag: v5.15~3931^2~34
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=2761121af87de45951989a0adada917837d8fa82;p=platform%2Fkernel%2Flinux-starfive.git

net_sched: sch_skbprio: add message validation to skbprio_change()

Do not assume the attribute has the right size.

Fixes: aea5f654e6b7 ("net/sched: add skbprio scheduler")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sched/sch_skbprio.c b/net/sched/sch_skbprio.c
index 0fb10abf7579..7a5e4c454715 100644
--- a/net/sched/sch_skbprio.c
+++ b/net/sched/sch_skbprio.c
@@ -169,6 +169,9 @@ static int skbprio_change(struct Qdisc *sch, struct nlattr *opt,
 {
 	struct tc_skbprio_qopt *ctl = nla_data(opt);
 
+	if (opt->nla_len != nla_attr_size(sizeof(*ctl)))
+		return -EINVAL;
+
 	sch->limit = ctl->limit;
 	return 0;
 }