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Date:   Thu, 31 Mar 2022 11:09:03 +0200
From:   Greg KH <gregkh@linuxfoundation.org>
To:     xkernel.wang@foxmail.com
Cc:     dan.carpenter@oracle.com, Larry.Finger@lwfinger.net,
        phil@philpotter.co.uk, linux-staging@lists.linux.dev,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] staging: r8188eu: change the allocation type of
 pdata_attr
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On Thu, Mar 31, 2022 at 03:37:00PM +0800, xkernel.wang@foxmail.com wrote:
> From: Xiaoke Wang <xkernel.wang@foxmail.com>
> 
> `pdata_attr` was allocated by kzalloc() in go_add_group_info_attr(), but
> there is a lack of error handlers along the call chain it lies and the
> lifetime of `pdata_attr` is only in go_add_group_info_attr().
> Therefore, changing it to a local variable on stack like the other
> functions in rtw_p2p.c is a possible choice, such as
> `u8 p2pie[MAX_P2P_IE_LEN] = { 0x00 };` in build_probe_resp_p2p_ie()
> which is the caller of go_add_group_info_attr().
> 
> Signed-off-by: Xiaoke Wang <xkernel.wang@foxmail.com>
> ---
>  drivers/staging/r8188eu/core/rtw_p2p.c | 6 ++----
>  1 file changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/staging/r8188eu/core/rtw_p2p.c b/drivers/staging/r8188eu/core/rtw_p2p.c
> index e2b6cf2..f1a5df8 100644
> --- a/drivers/staging/r8188eu/core/rtw_p2p.c
> +++ b/drivers/staging/r8188eu/core/rtw_p2p.c
> @@ -27,15 +27,14 @@ static u32 go_add_group_info_attr(struct wifidirect_info *pwdinfo, u8 *pbuf)
>  	struct list_head *phead, *plist;
>  	u32 len = 0;
>  	u16 attr_len = 0;
> -	u8 tmplen, *pdata_attr, *pstart, *pcur;
> +	u8 pdata_attr[MAX_P2P_IE_LEN] = { 0x00 };

As I said before, this is way too big to put on the stack.