From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 18 Feb 2019 09:26:32 +0000 (+0300)
Subject: net: sched: potential NULL dereference in tcf_block_find()
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=af736bf071e8ccf395fa7f7d9d105e020cf609cc;p=openwrt%2Fstaging%2Fblogic.git

net: sched: potential NULL dereference in tcf_block_find()

The error code isn't set on this path so it would result in returning
ERR_PTR(0) and a NULL dereference in the caller.

Fixes: 18d3eefb17cf ("net: sched: refactor tcf_block_find() into standalone functions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 9ad53895e604..28592e9f803f 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1309,8 +1309,10 @@ static struct tcf_block *tcf_block_find(struct net *net, struct Qdisc **q,
 		goto errout_qdisc;
 
 	block = __tcf_block_find(net, *q, *cl, ifindex, block_index, extack);
-	if (IS_ERR(block))
+	if (IS_ERR(block)) {
+		err = PTR_ERR(block);
 		goto errout_qdisc;
+	}
 
 	return block;