[PATCH AUTOSEL for 4.9 07/24] staging: rtl8188eu: avoid a null dereference on pmlmepriv

From: alexander . levin
Date: Wed Nov 22 2017 - 17:37:35 EST


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

[ Upstream commit 123c0aab0050cd0e07ce18e453389fbbb0a5a425 ]

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>

Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/staging/rtl8188eu/core/rtw_mlme.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_mlme.c b/drivers/staging/rtl8188eu/core/rtw_mlme.c
index ee2dcd05010f..0b60d1e0333e 100644
--- a/drivers/staging/rtl8188eu/core/rtw_mlme.c
+++ b/drivers/staging/rtl8188eu/core/rtw_mlme.c
@@ -107,10 +107,10 @@ void rtw_free_mlme_priv_ie_data(struct mlme_priv *pmlmepriv)

void rtw_free_mlme_priv(struct mlme_priv *pmlmepriv)
{
- rtw_free_mlme_priv_ie_data(pmlmepriv);
-
- if (pmlmepriv)
+ if (pmlmepriv) {
+ rtw_free_mlme_priv_ie_data(pmlmepriv);
vfree(pmlmepriv->free_bss_buf);
+ }
}

struct wlan_network *_rtw_alloc_network(struct mlme_priv *pmlmepriv)
--
2.11.0