Staging: vt6655-6: potential NULL dereference in hostap_disable_hostapd()

commit cb4855b49deb1acce27706ad9509d63c4fe8e988 upstream.

We fixed this to use free_netdev() instead of kfree() but unfortunately
free_netdev() doesn't accept NULL pointers.  Smatch complains about
this, it's not something I discovered through testing.

Fixes: 3030d40b5036 ('staging: vt6655: use free_netdev instead of kfree')
Fixes: 0a438d5b381e ('staging: vt6656: use free_netdev instead of kfree')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[wt: only vt6656 was converted to free_netdev in 3.10]
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/drivers/staging/vt6656/hostap.c b/drivers/staging/vt6656/hostap.c
index c699a3058b39920a34daf1a6f63524be990e29cb..cfffdd20e4358ff91c79d22d46d64589d8289088 100644 (file)
--- a/drivers/staging/vt6656/hostap.c
+++ b/drivers/staging/vt6656/hostap.c
@@ -133,7 +133,8 @@ static int hostap_disable_hostapd(struct vnt_private *pDevice, int rtnl_locked)
             DBG_PRT(MSG_LEVEL_DEBUG, KERN_INFO "%s: Netdevice %s unregistered\n",
                       pDevice->dev->name, pDevice->apdev->name);
        }
-       free_netdev(pDevice->apdev);
+       if (pDevice->apdev)
+               free_netdev(pDevice->apdev);
        pDevice->apdev = NULL;
     pDevice->bEnable8021x = false;
     pDevice->bEnableHostWEP = false;