Subject: [PATCH net 2/2] net: dsa: tag_ar9331: Make sure there is headroom for tag

From: Per Forlin <[email-masked]>
Date: Thu, 13 Feb 2020 15:37:10 +0100

Passing tag size to skb_cow_head will make sure
there is enough headroom for the tag data.
This change does not introduce any overhead in case there
is already available headroom for tag.

Signed-off-by: Per Forlin <[email-masked]>
---
 net/dsa/tag_ar9331.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/dsa/tag_ar9331.c b/net/dsa/tag_ar9331.c
index 466ffa92a474..55b00694cdba 100644
--- a/net/dsa/tag_ar9331.c
+++ b/net/dsa/tag_ar9331.c
@@ -31,7 +31,7 @@ static struct sk_buff *ar9331_tag_xmit(struct sk_buff *skb,
 	__le16 *phdr;
 	u16 hdr;
 
-	if (skb_cow_head(skb, 0) < 0)
+	if (skb_cow_head(skb, AR9331_HDR_LEN) < 0)
 		return NULL;
 
 	phdr = skb_push(skb, AR9331_HDR_LEN);
-- 
2.11.0