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

[Dan Carpenter]

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 at oracle.com>

diff --git a/drivers/staging/vt6655/hostap.c b/drivers/staging/vt6655/hostap.c
index aab0012..ab8b2ba 100644
--- a/drivers/staging/vt6655/hostap.c
+++ b/drivers/staging/vt6655/hostap.c
@@ -143,7 +143,8 @@ static int hostap_disable_hostapd(PSDevice 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;
diff --git a/drivers/staging/vt6656/hostap.c b/drivers/staging/vt6656/hostap.c
index ae1676d..67ba48b 100644
--- 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;