From: Zhouyang Jia <jiazhouyang09@gmail.com>
Date: Mon, 11 Jun 2018 05:26:35 +0000 (+0800)
Subject: net: dsa: add error handling for pskb_trim_rcsum
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=349b71d6f427ff8211adf50839dbbff3f27c1805;p=openwrt%2Fstaging%2Fblogic.git

net: dsa: add error handling for pskb_trim_rcsum

When pskb_trim_rcsum fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling pskb_trim_rcsum.

Signed-off-by: Zhouyang Jia <jiazhouyang09@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/dsa/tag_trailer.c b/net/dsa/tag_trailer.c
index 7d20e1f3de28..56197f0d9608 100644
--- a/net/dsa/tag_trailer.c
+++ b/net/dsa/tag_trailer.c
@@ -75,7 +75,8 @@ static struct sk_buff *trailer_rcv(struct sk_buff *skb, struct net_device *dev,
 	if (!skb->dev)
 		return NULL;
 
-	pskb_trim_rcsum(skb, skb->len - 4);
+	if (pskb_trim_rcsum(skb, skb->len - 4))
+		return NULL;
 
 	return skb;
 }