Re: [PATCH v3] staging: rtl8188eu: Fix potential NULL pointer dereference of kcalloc

[Mukesh Ojha]

On 3/20/2019 10:51 PM, Aditya Pakki wrote:
hwxmits is allocated via kcalloc and not checked for failure before its

No need to mention  kcalloc as the other place allocates the memory 
through kmalloc.

Otherwise looks good.
Acked-by: Mukesh Ojha <mo...@codeaurora.org>

dereference. The patch fixes this problem by returning error upstream
in rtl8723bs, rtl8188eu.

Signed-off-by: Aditya Pakki <pakki...@umn.edu>

---
v2: Move signed off above version change log.
v1: Return error and remove print in case of failure, per Greg
---
  drivers/staging/rtl8188eu/core/rtw_xmit.c    |  9 +++++++--
  drivers/staging/rtl8188eu/include/rtw_xmit.h |  2 +-
  drivers/staging/rtl8723bs/core/rtw_xmit.c    | 14 +++++++-------
  drivers/staging/rtl8723bs/include/rtw_xmit.h |  2 +-
  4 files changed, 16 insertions(+), 11 deletions(-)

diff --git a/drivers/staging/rtl8188eu/core/rtw_xmit.c 
b/drivers/staging/rtl8188eu/core/rtw_xmit.c
index 1723a47a96b4..952f2ab51347 100644
--- a/drivers/staging/rtl8188eu/core/rtw_xmit.c
+++ b/drivers/staging/rtl8188eu/core/rtw_xmit.c
@@ -174,7 +174,9 @@ s32 _rtw_init_xmit_priv(struct xmit_priv *pxmitpriv, struct 
adapter *padapter)
  
  	pxmitpriv->free_xmit_extbuf_cnt = num_xmit_extbuf;
  
-	rtw_alloc_hwxmits(padapter);
+       res = rtw_alloc_hwxmits(padapter);
+       if (res == _FAIL)
+               goto exit;
        rtw_init_hwxmits(pxmitpriv->hwxmits, pxmitpriv->hwxmit_entry);
  
  	for (i = 0; i < 4; i++)
@@ -1503,7 +1505,7 @@ s32 rtw_xmit_classifier(struct adapter *padapter, struct 
xmit_frame *pxmitframe)
        return res;
  }
  
-void rtw_alloc_hwxmits(struct adapter *padapter)
+s32 rtw_alloc_hwxmits(struct adapter *padapter)
  {
        struct hw_xmit *hwxmits;
        struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
@@ -1512,6 +1514,8 @@ void rtw_alloc_hwxmits(struct adapter *padapter)
  
  	pxmitpriv->hwxmits = kcalloc(pxmitpriv->hwxmit_entry,
                                     sizeof(struct hw_xmit), GFP_KERNEL);
+       if (!pxmitpriv->hwxmits)
+               return _FAIL;
  
  	hwxmits = pxmitpriv->hwxmits;
  
@@ -1519,6 +1523,7 @@ void rtw_alloc_hwxmits(struct adapter *padapter)
        hwxmits[1] .sta_queue = &pxmitpriv->vi_pending;
        hwxmits[2] .sta_queue = &pxmitpriv->be_pending;
        hwxmits[3] .sta_queue = &pxmitpriv->bk_pending;
+       return _SUCCESS;
  }
  
  void rtw_free_hwxmits(struct adapter *padapter)
diff --git a/drivers/staging/rtl8188eu/include/rtw_xmit.h 
b/drivers/staging/rtl8188eu/include/rtw_xmit.h
index 788f59c74ea1..ba7e15fbde72 100644
--- a/drivers/staging/rtl8188eu/include/rtw_xmit.h
+++ b/drivers/staging/rtl8188eu/include/rtw_xmit.h
@@ -336,7 +336,7 @@ s32 rtw_txframes_sta_ac_pending(struct adapter *padapter,
  void rtw_init_hwxmits(struct hw_xmit *phwxmit, int entry);
  s32 _rtw_init_xmit_priv(struct xmit_priv *pxmitpriv, struct adapter 
*padapter);
  void _rtw_free_xmit_priv(struct xmit_priv *pxmitpriv);
-void rtw_alloc_hwxmits(struct adapter *padapter);
+s32 rtw_alloc_hwxmits(struct adapter *padapter);
  void rtw_free_hwxmits(struct adapter *padapter);
  s32 rtw_xmit(struct adapter *padapter, struct sk_buff **pkt);
  
diff --git a/drivers/staging/rtl8723bs/core/rtw_xmit.c b/drivers/staging/rtl8723bs/core/rtw_xmit.c
index 094d61bcb469..b87f13a0b563 100644
--- a/drivers/staging/rtl8723bs/core/rtw_xmit.c
+++ b/drivers/staging/rtl8723bs/core/rtw_xmit.c
@@ -260,7 +260,9 @@ s32 _rtw_init_xmit_priv(struct xmit_priv *pxmitpriv, struct 
adapter *padapter)
                }
        }
  
-	rtw_alloc_hwxmits(padapter);
+       res = rtw_alloc_hwxmits(padapter);
+       if (res == _FAIL)
+               goto exit;
        rtw_init_hwxmits(pxmitpriv->hwxmits, pxmitpriv->hwxmit_entry);
  
  	for (i = 0; i < 4; i++) {
@@ -2144,7 +2146,7 @@ s32 rtw_xmit_classifier(struct adapter *padapter, struct 
xmit_frame *pxmitframe)
        return res;
  }
  
-void rtw_alloc_hwxmits(struct adapter *padapter)
+s32 rtw_alloc_hwxmits(struct adapter *padapter)
  {
        struct hw_xmit *hwxmits;
        struct xmit_priv *pxmitpriv = &padapter->xmitpriv;
@@ -2155,10 +2157,8 @@ void rtw_alloc_hwxmits(struct adapter *padapter)
  
  	pxmitpriv->hwxmits = rtw_zmalloc(sizeof(struct hw_xmit) * pxmitpriv->hwxmit_entry);
  
-	if (pxmitpriv->hwxmits == NULL) {
-               DBG_871X("alloc hwxmits fail!...\n");
-               return;
-       }
+       if (!pxmitpriv->hwxmits)
+               return _FAIL;
  
  	hwxmits = pxmitpriv->hwxmits;
  
@@ -2204,7 +2204,7 @@ void rtw_alloc_hwxmits(struct adapter *padapter)
  
  	}
  
-
+       return _SUCCESS;
  }
  
  void rtw_free_hwxmits(struct adapter *padapter)
diff --git a/drivers/staging/rtl8723bs/include/rtw_xmit.h 
b/drivers/staging/rtl8723bs/include/rtw_xmit.h
index 1b38b9182b31..37f42b2f22f1 100644
--- a/drivers/staging/rtl8723bs/include/rtw_xmit.h
+++ b/drivers/staging/rtl8723bs/include/rtw_xmit.h
@@ -487,7 +487,7 @@ s32 _rtw_init_xmit_priv(struct xmit_priv *pxmitpriv, struct 
adapter *padapter);
  void _rtw_free_xmit_priv (struct xmit_priv *pxmitpriv);
  
  
-void rtw_alloc_hwxmits(struct adapter *padapter);
+s32 rtw_alloc_hwxmits(struct adapter *padapter);
  void rtw_free_hwxmits(struct adapter *padapter);