[PATCH v2] staging: r8188eu: fix a potential memory leak in _rtw_init_cmd_priv()

[PATCH v2] staging: r8188eu: fix a potential memory leak in _rtw_init_cmd_priv()

[xkernel.wang]

From: Xiaoke Wang <xkernel.wang@foxmail.com>

In _rtw_init_cmd_priv(), if `pcmdpriv->rsp_allocated_buf` is allocated
in failure, `pcmdpriv->cmd_allocated_buf` is not properly released.
This patch is to free it.

Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
---
ChangeLog:
v1->v2: simplify the function.
 drivers/staging/r8188eu/core/rtw_cmd.c | 21 +++++----------------
 1 file changed, 5 insertions(+), 16 deletions(-)

diff --git a/drivers/staging/r8188eu/core/rtw_cmd.c b/drivers/staging/r8188eu/core/rtw_cmd.c
index 56910c3..3de3a39 100644
--- a/drivers/staging/r8188eu/core/rtw_cmd.c
+++ b/drivers/staging/r8188eu/core/rtw_cmd.c
@@ -17,8 +17,6 @@ No irqsave is necessary.
 
 static int _rtw_init_cmd_priv(struct cmd_priv *pcmdpriv)
 {
-	int res = _SUCCESS;
-
 	sema_init(&pcmdpriv->cmd_queue_sema, 0);
 	/* sema_init(&(pcmdpriv->cmd_done_sema), 0); */
 	sema_init(&pcmdpriv->terminate_cmdthread_sema, 0);
@@ -26,34 +24,25 @@ static int _rtw_init_cmd_priv(struct cmd_priv *pcmdpriv)
 	_rtw_init_queue(&pcmdpriv->cmd_queue);
 
 	/* allocate DMA-able/Non-Page memory for cmd_buf and rsp_buf */
-
 	pcmdpriv->cmd_seq = 1;
-
 	pcmdpriv->cmd_allocated_buf = kzalloc(MAX_CMDSZ + CMDBUFF_ALIGN_SZ,
 					      GFP_KERNEL);
-
-	if (!pcmdpriv->cmd_allocated_buf) {
-		res = _FAIL;
-		goto exit;
-	}
+	if (!pcmdpriv->cmd_allocated_buf)
+		return _FAIL;
 
 	pcmdpriv->cmd_buf = pcmdpriv->cmd_allocated_buf  +  CMDBUFF_ALIGN_SZ - ((size_t)(pcmdpriv->cmd_allocated_buf) & (CMDBUFF_ALIGN_SZ - 1));
-
 	pcmdpriv->rsp_allocated_buf = kzalloc(MAX_RSPSZ + 4, GFP_KERNEL);
-
 	if (!pcmdpriv->rsp_allocated_buf) {
-		res = _FAIL;
-		goto exit;
+		kfree(pcmdpriv->cmd_allocated_buf);
+		return _FAIL;
 	}
 
 	pcmdpriv->rsp_buf = pcmdpriv->rsp_allocated_buf  +  4 - ((size_t)(pcmdpriv->rsp_allocated_buf) & 3);
-
 	pcmdpriv->cmd_issued_cnt = 0;
 	pcmdpriv->cmd_done_cnt = 0;
 	pcmdpriv->rsp_cnt = 0;
-exit:
 
-	return res;
+	return _SUCCESS;
 }
 
 static void c2h_wk_callback(struct work_struct *work);
-- 

Re: [PATCH v2] staging: r8188eu: fix a potential memory leak in _rtw_init_cmd_priv()

[Greg KH]

On Thu, Mar 31, 2022 at 12:15:35AM +0800, xkernel.wang@foxmail.com wrote:
> From: Xiaoke Wang <xkernel.wang@foxmail.com>
> 
> In _rtw_init_cmd_priv(), if `pcmdpriv->rsp_allocated_buf` is allocated
> in failure, `pcmdpriv->cmd_allocated_buf` is not properly released.
> This patch is to free it.
> 
> Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
> ---
> ChangeLog:
> v1->v2: simplify the function.
>  drivers/staging/r8188eu/core/rtw_cmd.c | 21 +++++----------------
>  1 file changed, 5 insertions(+), 16 deletions(-)
> 
> diff --git a/drivers/staging/r8188eu/core/rtw_cmd.c b/drivers/staging/r8188eu/core/rtw_cmd.c
> index 56910c3..3de3a39 100644
> --- a/drivers/staging/r8188eu/core/rtw_cmd.c
> +++ b/drivers/staging/r8188eu/core/rtw_cmd.c
> @@ -17,8 +17,6 @@ No irqsave is necessary.
>  
>  static int _rtw_init_cmd_priv(struct cmd_priv *pcmdpriv)
>  {
> -	int res = _SUCCESS;
> -
>  	sema_init(&pcmdpriv->cmd_queue_sema, 0);
>  	/* sema_init(&(pcmdpriv->cmd_done_sema), 0); */
>  	sema_init(&pcmdpriv->terminate_cmdthread_sema, 0);
> @@ -26,34 +24,25 @@ static int _rtw_init_cmd_priv(struct cmd_priv *pcmdpriv)
>  	_rtw_init_queue(&pcmdpriv->cmd_queue);
>  
>  	/* allocate DMA-able/Non-Page memory for cmd_buf and rsp_buf */
> -
>  	pcmdpriv->cmd_seq = 1;
> -

Why make whitespace cleanups at the same time?  Please do not do that.

And I do not think this patch applies anymore _rtw_init_queue() is not
in my tree.  Please rebase and fix up and resend.

thanks,

greg k-h