Re: [PATCH v3] staging: rtl8723bs: fix ie_length bound check in rtw_cfg80211_inform_bss

[Greg KH <gregkh@linuxfoundation.org>]

On Fri, Oct 02, 2026 at 02:04:50PM +0000, Adi Prasan wrote:
> The buffer bound check in rtw_cfg80211_inform_bss() checked bssinf_len
> (ie_length + header size) against MAX_BSSINFO_LEN (1000 bytes), but
> network.ies[] is only MAX_IE_SZ (768) bytes. This allowed ie_length
> values up to ~976 bytes to pass the check while a subsequent memcpy()
> from network.ies still only has 768 valid bytes, and other paths that
> write to network.ies consistently cap ie_length to MAX_IE_SZ.
> 
> Check ie_length against MAX_IE_SZ directly, which is the actual size
> of network.ies, and drop the now-unused bssinf_len/MAX_BSSINFO_LEN
> comparison.
> 
> Signed-off-by: Adi Prasan <itsadi2409@gmail.com>
> Fixes: 554c0a3abf216 ("staging: Add rtl8723bs sdio wifi driver")
> ---
>  drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c b/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c
> index 27e7b8442d7b..7e964b15ae6d 100644
> --- a/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c
> +++ b/drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c
> @@ -210,7 +210,7 @@ struct cfg80211_bss *rtw_cfg80211_inform_bss(struct adapter *padapter, struct wl
>  	u64 notify_timestamp;
>  	s32 notify_signal;
>  	u8 *buf = NULL, *pbuf;
> -	size_t len, bssinf_len = 0;
> +	size_t len;
>  	struct ieee80211_hdr *pwlanhdr;
>  	__le16 *fctrl;
>  
> @@ -218,8 +218,7 @@ struct cfg80211_bss *rtw_cfg80211_inform_bss(struct adapter *padapter, struct wl
>  	struct wiphy *wiphy = wdev->wiphy;
>  	struct mlme_priv *pmlmepriv = &(padapter->mlmepriv);
>  
> -	bssinf_len = pnetwork->network.ie_length + sizeof(struct ieee80211_hdr_3addr);
> -	if (bssinf_len > MAX_BSSINFO_LEN || pnetwork->network.ie_length > MAX_IE_SZ)
> +	if (pnetwork->network.ie_length > MAX_IE_SZ)
>  		goto exit;
>  
>  	{
> -- 
> 2.43.0
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
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If you wish to discuss this problem further, or you have questions about
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thanks,

greg k-h's patch email bot