Re: [PATCH] wifi: ath12k: fix potential NULL dereference

[Jeff Johnson]

On 6/14/2024 10:32 AM, Dan Carpenter wrote:
> In this condition if "sband" is NULL then it leads to a NULL dereference
> on the next line when it does "idx -= sband->n_channels;".
> 
> The condition can just be deleted, because if "sband" is NULL or the
> "idx" is out of bounds, then the correct thing is to at this point is to
> return -ENOENT.  There are no additional sbands available to try.
> 
> Fixes: 70e3be54bbdd ("wifi: ath12k: fix survey dump collection in 6 GHz")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> ---
>  drivers/net/wireless/ath/ath12k/mac.c | 5 -----
>  1 file changed, 5 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
> index 509c02bffdae..e5456383dabd 100644
> --- a/drivers/net/wireless/ath/ath12k/mac.c
> +++ b/drivers/net/wireless/ath/ath12k/mac.c
> @@ -8314,11 +8314,6 @@ static int ath12k_mac_op_get_survey(struct ieee80211_hw *hw, int idx,
>  
>  	if (!sband)
>  		sband = hw->wiphy->bands[NL80211_BAND_6GHZ];
> -	if (!sband || idx >= sband->n_channels) {
> -		idx -= sband->n_channels;
> -		sband = NULL;
> -	}
> -
>  	if (!sband || idx >= sband->n_channels)
>  		return -ENOENT;
>  
This duplicates
https://lore.kernel.org/all/20240611031017.297927-2-quic_aarasahu@xxxxxxxxxxx/