The variable skb is released via kfree_skb() when the return value of
_rtl92e_tx is not zero. However, after that, skb is accessed again to
read its length, which may result in a use after free bug. This patch
fixes the bug by moving the release operation to where skb is never
used later.

Signed-off-by: Pan Bian <bianpan2...@163.com>
---
 drivers/staging/rtl8192e/rtl8192e/rtl_core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/rtl8192e/rtl8192e/rtl_core.c 
b/drivers/staging/rtl8192e/rtl8192e/rtl_core.c
index f932cb15e4e5..cdcb22f96ed9 100644
--- a/drivers/staging/rtl8192e/rtl8192e/rtl_core.c
+++ b/drivers/staging/rtl8192e/rtl8192e/rtl_core.c
@@ -1616,14 +1616,15 @@ static void _rtl92e_hard_data_xmit(struct sk_buff *skb, 
struct net_device *dev,
        memcpy((unsigned char *)(skb->cb), &dev, sizeof(dev));
        skb_push(skb, priv->rtllib->tx_headroom);
        ret = _rtl92e_tx(dev, skb);
-       if (ret != 0)
-               kfree_skb(skb);
 
        if (queue_index != MGNT_QUEUE) {
                priv->rtllib->stats.tx_bytes += (skb->len -
                                                 priv->rtllib->tx_headroom);
                priv->rtllib->stats.tx_packets++;
        }
+
+       if (ret != 0)
+               kfree_skb(skb);
 }
 
 static int _rtl92e_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
-- 
2.7.4

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