Re: [PATCH] staging: rtlwifi: check for array overflow

[Larry Finger <Larry.Finger@xxxxxxxxxxxx>]

On 08/24/2017 05:08 AM, Dan Carpenter wrote:
> Smatch is distrustful of the "capab" value and marks it as user
> controlled.  I think it actually comes from the firmware?  Anyway, I
> looked at other drivers and they added a bounds check and it seems like
> a harmless thing to have so I have added it here as well.
>
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

Acked-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>

Thanks,

Larry

> diff --git a/drivers/staging/rtlwifi/base.c b/drivers/staging/rtlwifi/base.c
> index f7f207cbaee3..a30b928d5ee1 100644
> --- a/drivers/staging/rtlwifi/base.c
> +++ b/drivers/staging/rtlwifi/base.c
> @@ -1414,6 +1414,10 @@ bool rtl_action_proc(struct ieee80211_hw *hw, struct sk_buff *skb, u8 is_tx)
>   				  le16_to_cpu(mgmt->u.action.u.addba_req.capab);
>   				tid = (capab &
>   				       IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
> +				if (tid >= MAX_TID_COUNT) {
> +					rcu_read_unlock();
> +					return true;
> +				}
>   				tid_data = &sta_entry->tids[tid];
>   				if (tid_data->agg.rx_agg_state ==
>   				    RTL_RX_AGG_START)