diff options
author | Larry Finger <Larry.Finger@lwfinger.net> | 2016-01-05 02:30:58 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-02-08 04:17:18 (GMT) |
commit | d0aaa57df2d8f5d355c64935dcff58cd4ab9fe2f (patch) | |
tree | d3623b8d353f8a1d1d2b37061e44b76817234f04 | |
parent | f06104fb322524eb8102c49c1fd916d901a81ee3 (diff) | |
download | linux-d0aaa57df2d8f5d355c64935dcff58cd4ab9fe2f.tar.xz |
staging: r8192U: Fix check pointer after usage problem
In routine rtl8192_tx_isr(), pointer skb is dereferenced before it is
checked for NULL. This patch has only been compile-tested, as I do not
have the hardware. This problem was reported at
https://bugzilla.kernel.org/show_bug.cgi?id=109951.
Fixes: bugzilla.kernel.org: #109951
Reported-by: Yong Shi <brave_shi@163.com>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Yong Shi <brave_shi@163.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/staging/rtl8192u/r8192U_core.c | 21 |
1 files changed, 13 insertions, 8 deletions
diff --git a/drivers/staging/rtl8192u/r8192U_core.c b/drivers/staging/rtl8192u/r8192U_core.c index 07f4e7a..3c58963 100644 --- a/drivers/staging/rtl8192u/r8192U_core.c +++ b/drivers/staging/rtl8192u/r8192U_core.c @@ -1092,10 +1092,17 @@ static int rtl8192_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) static void rtl8192_tx_isr(struct urb *tx_urb) { struct sk_buff *skb = (struct sk_buff *)tx_urb->context; - struct net_device *dev = (struct net_device *)(skb->cb); + struct net_device *dev; struct r8192_priv *priv = NULL; - cb_desc *tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE); - u8 queue_index = tcb_desc->queue_index; + cb_desc *tcb_desc; + u8 queue_index; + + if (!skb) + return; + + dev = (struct net_device *)(skb->cb); + tcb_desc = (cb_desc *)(skb->cb + MAX_DEV_ADDR_SIZE); + queue_index = tcb_desc->queue_index; priv = ieee80211_priv(dev); @@ -1113,11 +1120,9 @@ static void rtl8192_tx_isr(struct urb *tx_urb) } /* free skb and tx_urb */ - if (skb != NULL) { - dev_kfree_skb_any(skb); - usb_free_urb(tx_urb); - atomic_dec(&priv->tx_pending[queue_index]); - } + dev_kfree_skb_any(skb); + usb_free_urb(tx_urb); + atomic_dec(&priv->tx_pending[queue_index]); /* * Handle HW Beacon: |