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

Julia Lawall
2011-10-28T23:58:13Z

From: Julia Lawall <julia@diku.dk>

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@diku.dk>

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

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;