[PATCH] rndis_wlan: move the dereference below the NULL test

Subsystems: networking drivers (wireless), the rest

STALE5084d

2 messages, 2 authors, 2012-09-10 · open the first message on its own page

[PATCH] rndis_wlan: move the dereference below the NULL test

From: Wei Yongjun <hidden>
Date: 2012-09-10 04:46:47

From: Wei Yongjun <redacted>

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)

Signed-off-by: Wei Yongjun <redacted>
---
 drivers/net/wireless/rndis_wlan.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/rndis_wlan.c b/drivers/net/wireless/rndis_wlan.c
index 7a4ae9e..de2a673 100644
--- a/drivers/net/wireless/rndis_wlan.c
+++ b/drivers/net/wireless/rndis_wlan.c
@@ -1946,12 +1946,19 @@ static int rndis_get_tx_power(struct wiphy *wiphy, int *dbm)
 static int rndis_scan(struct wiphy *wiphy,
 			struct cfg80211_scan_request *request)
 {
-	struct net_device *dev = request->wdev->netdev;
-	struct usbnet *usbdev = netdev_priv(dev);
-	struct rndis_wlan_private *priv = get_rndis_wlan_priv(usbdev);
+	struct net_device *dev;
+	struct usbnet *usbdev;
+	struct rndis_wlan_private *priv;
 	int ret;
 	int delay = SCAN_DELAY_JIFFIES;
 
+	if (!request)
+		return -EINVAL;
+
+	dev = request->wdev->netdev;
+	usbdev = netdev_priv(dev);
+	priv = get_rndis_wlan_priv(usbdev);
+
 	netdev_dbg(usbdev->net, "cfg80211.scan\n");
 
 	/* Get current bssid list from device before new scan, as new scan
@@ -1959,9 +1966,6 @@ static int rndis_scan(struct wiphy *wiphy,
 	 */
 	rndis_check_bssid_list(usbdev, NULL, NULL);
 
-	if (!request)
-		return -EINVAL;
-
 	if (priv->scan_request && priv->scan_request != request)
 		return -EBUSY;
 

Re: [PATCH] rndis_wlan: move the dereference below the NULL test

From: Jussi Kivilinna <hidden>
Date: 2012-09-10 06:29:57

Quoting Wei Yongjun [off-list ref]:
quoted hunk
From: Wei Yongjun <redacted>

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)

Signed-off-by: Wei Yongjun <redacted>
---
 drivers/net/wireless/rndis_wlan.c | 16 ++++++++++------
 1 file changed, 10 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/rndis_wlan.c  
b/drivers/net/wireless/rndis_wlan.c
index 7a4ae9e..de2a673 100644
--- a/drivers/net/wireless/rndis_wlan.c
+++ b/drivers/net/wireless/rndis_wlan.c
@@ -1946,12 +1946,19 @@ static int rndis_get_tx_power(struct wiphy  
*wiphy, int *dbm)
 static int rndis_scan(struct wiphy *wiphy,
 			struct cfg80211_scan_request *request)
 {
-	struct net_device *dev = request->wdev->netdev;
-	struct usbnet *usbdev = netdev_priv(dev);
-	struct rndis_wlan_private *priv = get_rndis_wlan_priv(usbdev);
+	struct net_device *dev;
+	struct usbnet *usbdev;
+	struct rndis_wlan_private *priv;
 	int ret;
 	int delay = SCAN_DELAY_JIFFIES;

+	if (!request)
+		return -EINVAL;
+
+	dev = request->wdev->netdev;
+	usbdev = netdev_priv(dev);
+	priv = get_rndis_wlan_priv(usbdev);
+
'request' is actually always valid pointer and the !request check is  
unneeded. Correct fix is to remove the check.
quoted hunk
 	netdev_dbg(usbdev->net, "cfg80211.scan\n");

 	/* Get current bssid list from device before new scan, as new scan
@@ -1959,9 +1966,6 @@ static int rndis_scan(struct wiphy *wiphy,
 	 */
 	rndis_check_bssid_list(usbdev, NULL, NULL);

-	if (!request)
-		return -EINVAL;
-
Only this part is needed.

-Jussi
 	if (priv->scan_request && priv->scan_request != request)
 		return -EBUSY;
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help