[PATCH 5.4 004/344] net: dsa: tag_qca: Make sure there is headroom for tag

Greg Kroah-Hartman
2020-02-21T08:02:24Z

From: Per Forlin <per.forlin@axis.com>

[ Upstream commit 04fb91243a853dbde216d829c79d9632e52aa8d9 ]

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 <perfn@axis.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/dsa/tag_qca.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/dsa/tag_qca.c
+++ b/net/dsa/tag_qca.c
@@ -33,7 +33,7 @@ static struct sk_buff *qca_tag_xmit(stru
struct dsa_port *dp = dsa_slave_to_port(dev);
u16 *phdr, hdr;

- if (skb_cow_head(skb, 0) < 0)
+ if (skb_cow_head(skb, QCA_HDR_LEN) < 0)
return NULL;

skb_push(skb, QCA_HDR_LEN);