[PATCH] brcmfmac: Ensure pointer correctly set if skb data location changes

[James Hughes]

The incoming skb header may be resized if header space is
insufficient, which might change the data adddress in the skb.
Ensure that a cached pointer to that data is correctly set by
moving assignment to after any possible changes.

Signed-off-by: James Hughes <james.hug...@raspberrypi.org>
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c 
b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
index 5eaac13e2317..934fe00e28a0 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c
@@ -198,7 +198,7 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff 
*skb,
        int ret;
        struct brcmf_if *ifp = netdev_priv(ndev);
        struct brcmf_pub *drvr = ifp->drvr;
-       struct ethhdr *eh = (struct ethhdr *)(skb->data);
+       struct ethhdr *eh;
 
        brcmf_dbg(DATA, "Enter, bsscfgidx=%d\n", ifp->bsscfgidx);
 
@@ -229,6 +229,8 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff 
*skb,
                }
        }
 
+       eh = (struct ethhdr *)(skb->data);
+
        /* validate length for ether packet */
        if (skb->len < sizeof(*eh)) {
                ret = -EINVAL;
-- 
2.11.0