Subject: Re: [PATCH v2] rtlwifi: Fix potential overflow on P2P code

From: Pkshih <[email-masked]>
Date: Fri, 18 Oct 2019 12:35:43 +0000

On Fri, 2019-10-18 at 07:43 -0400, Laura Abbott wrote:
> Nicolas Waisman noticed that even though noa_len is checked for
> a compatible length it's still possible to overrun the buffers
> of p2pinfo since there's no check on the upper bound of noa_num.
> Bound noa_num against P2P_MAX_NOA_NUM.
> 
> Reported-by: Nicolas Waisman <[email-masked]>
> Signed-off-by: Laura Abbott <[email-masked]>

Acked-by: Ping-Ke Shih <[email-masked]>
and Please CC to stable
Cc: Stable <[email-masked]> # 4.4+

---

Hi Kalle,

This bug was existing since v3.10, and directory of wireless drivers were
moved at v4.4. Do I need send another patch to fix this issue for longterm
kernel v3.16.75?

Thanks
PK

> ---
> v2: Use P2P_MAX_NOA_NUM instead of erroring out.
> ---
>  drivers/net/wireless/realtek/rtlwifi/ps.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/drivers/net/wireless/realtek/rtlwifi/ps.c
> b/drivers/net/wireless/realtek/rtlwifi/ps.c
> index 70f04c2f5b17..fff8dda14023 100644
> --- a/drivers/net/wireless/realtek/rtlwifi/ps.c
> +++ b/drivers/net/wireless/realtek/rtlwifi/ps.c
> @@ -754,6 +754,9 @@ static void rtl_p2p_noa_ie(struct ieee80211_hw *hw, void
> *data,
>  				return;
>  			} else {
>  				noa_num = (noa_len - 2) / 13;
> +				if (noa_num > P2P_MAX_NOA_NUM)
> +					noa_num = P2P_MAX_NOA_NUM;
> +
>  			}
>  			noa_index = ie[3];
>  			if (rtlpriv->psc.p2p_ps_info.p2p_ps_mode ==
> @@ -848,6 +851,9 @@ static void rtl_p2p_action_ie(struct ieee80211_hw *hw,
> void *data,
>  				return;
>  			} else {
>  				noa_num = (noa_len - 2) / 13;
> +				if (noa_num > P2P_MAX_NOA_NUM)
> +					noa_num = P2P_MAX_NOA_NUM;
> +
>  			}
>  			noa_index = ie[3];
>  			if (rtlpriv->psc.p2p_ps_info.p2p_ps_mode ==