Re: [PATCH 1/5] drivers/staging/rtl8712/rtl871x_mlme.c: eliminatea null pointer dereference

From: Larry Finger
Date: Fri Oct 28 2011 - 21:05:44 EST


On 10/28/2011 06:58 PM, Julia Lawall wrote:
From: Julia Lawall<julia@xxxxxxx>

If ibss_wlan is NULL, it is not correct to memcpy into its field.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

//<smpl>
@r@
expression E, E1;
identifier f;
statement S1,S2,S3;
@@

if (E == NULL)
{
... when != if (E == NULL || ...) S1 else S2
when != E = E1
*E->f
... when any
return ...;
}
else S3
//</smpl>

Signed-off-by: Julia Lawall<julia@xxxxxxx>

---
I have no idea whether this is the correct fix.

I believe it is. It probably does not matter as I have never hit an oops at this location.

Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

drivers/staging/rtl8712/rtl871x_mlme.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/rtl8712/rtl871x_mlme.c b/drivers/staging/rtl8712/rtl871x_mlme.c
index ef8eb6c..4277d03 100644
--- a/drivers/staging/rtl8712/rtl871x_mlme.c
+++ b/drivers/staging/rtl8712/rtl871x_mlme.c
@@ -551,7 +551,7 @@ void r8712_survey_event_callback(struct _adapter *adapter, u8 *pbuf)
ibss_wlan = r8712_find_network(
&pmlmepriv->scanned_queue,
pnetwork->MacAddress);
- if (!ibss_wlan) {
+ if (ibss_wlan) {
memcpy(ibss_wlan->network.IEs,
pnetwork->IEs, 8);
goto exit;



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/