Received-SPF: pass (google.com: domain of linux-wireless+bounces-758-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Date: Wed, 13 Dec 2023 11:16:00 -0800
From: Kees Cook <keescook@chromium.org>
To: Jeff Johnson <quic_jjohnson@quicinc.com>
Cc: Kalle Valo <kvalo@kernel.org>,
	"Gustavo A. R. Silva" <gustavo@embeddedor.com>,
	ath10k@lists.infradead.org, linux-wireless@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 6/6] wifi: ath10k: remove duplicate memset() in 10.4 TDLS
 peer update
Message-ID: <202312131113.4C01D1DD5A@keescook>
References: <20231213-wmi_host_mem_chunks_flexarray-v1-0-92922d92fa2c@quicinc.com>
 <20231213-wmi_host_mem_chunks_flexarray-v1-6-92922d92fa2c@quicinc.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231213-wmi_host_mem_chunks_flexarray-v1-6-92922d92fa2c@quicinc.com>

On Wed, Dec 13, 2023 at 09:06:44AM -0800, Jeff Johnson wrote:
> In [1] it was identified that in ath10k_wmi_10_4_gen_tdls_peer_update()
> the memset(skb->data, 0, sizeof(*cmd)) is unnecessary since function
> ath10k_wmi_alloc_skb() already zeroes skb->data, so remove it.

Is .gen_tdls_peer_update only ever called after a fresh allocation? It
wasn't obvious to me as I tried to follow the call paths. Is there harm
in leaving this?

-Kees

> 
> No functional changes, compile tested only.
> 
> [1] https://lore.kernel.org/linux-wireless/626ae2e7-66f8-423b-b17f-e75c1a6d29b3@embeddedor.com/
> 
> Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
> ---
>  drivers/net/wireless/ath/ath10k/wmi.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath10k/wmi.c b/drivers/net/wireless/ath/ath10k/wmi.c
> index 4d5aadbc7159..0cfd9484c45e 100644
> --- a/drivers/net/wireless/ath/ath10k/wmi.c
> +++ b/drivers/net/wireless/ath/ath10k/wmi.c
> @@ -8918,8 +8918,6 @@ ath10k_wmi_10_4_gen_tdls_peer_update(struct ath10k *ar,
>  	if (!skb)
>  		return ERR_PTR(-ENOMEM);
>  
> -	memset(skb->data, 0, sizeof(*cmd));
> -
>  	cmd = (struct wmi_10_4_tdls_peer_update_cmd *)skb->data;
>  	cmd->vdev_id = __cpu_to_le32(arg->vdev_id);
>  	ether_addr_copy(cmd->peer_macaddr.addr, arg->addr);
> 
> -- 
> 2.42.0
> 

-- 
Kees Cook