[PATCH 3.16 048/136] staging: rtl8188eu: avoid a null dereference on pmlmepriv

[Ben Hutchings]

3.16.54-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

commit 123c0aab0050cd0e07ce18e453389fbbb0a5a425 upstream.

There is a check on pmlmepriv before dereferencing it when
vfree'ing pmlmepriv->free_bss_buf however the previous call
to rtw_free_mlme_priv_ie_data deferences pmlmepriv causing
a null pointer deference if it is null.  Avoid this by also
calling rtw_free_mlme_priv_ie_data if the pointer is non-null.

Detected by CoverityScan, CID#1230262 ("Dereference before null check")
Fixes: 7b464c9fa5cc ("staging: r8188eu: Add files for new driver - part 4")
Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
--- a/drivers/staging/rtl8188eu/core/rtw_mlme.c
+++ b/drivers/staging/rtl8188eu/core/rtw_mlme.c
@@ -120,9 +120,8 @@ void rtw_free_mlme_priv_ie_data(struct m
 
 void _rtw_free_mlme_priv(struct mlme_priv *pmlmepriv)
 {
-	rtw_free_mlme_priv_ie_data(pmlmepriv);
-
 	if (pmlmepriv) {
+		rtw_free_mlme_priv_ie_data(pmlmepriv);
 		if (pmlmepriv->free_bss_buf)
 			vfree(pmlmepriv->free_bss_buf);
 	}