Re: [PATCH] wifi: iwlegacy: Use kcalloc() instead of kzalloc()

[Gustavo A. R. Silva]

On 1/19/24 11:16, Erick Archer wrote:
> As noted in the "Deprecated Interfaces, Language Features, Attributes,
> and Conventions" documentation [1], size calculations (especially
> multiplication) should not be performed in memory allocator (or similar)
> function arguments due to the risk of them overflowing. This could lead
> to values wrapping around and a smaller allocation being made than the
> caller was expecting. Using those allocations could lead to linear
> overflows of heap memory and other misbehaviors.
>
> So, use the purpose specific kcalloc() function instead of the argument
> size * count in the kzalloc() function.
>
> Also, it is preferred to use sizeof(*pointer) instead of sizeof(type)
> due to the type of the variable can change and one needs not change the
> former (unlike the latter).
>
> Link: https://www.kernel.org/doc/html/next/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1]
> Link: https://github.com/KSPP/linux/issues/162
> Signed-off-by: Erick Archer <erick.archer@xxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks!
--
Gustavo

> ---
>   drivers/net/wireless/intel/iwlegacy/common.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/drivers/net/wireless/intel/iwlegacy/common.c b/drivers/net/wireless/intel/iwlegacy/common.c
> index 17570d62c896..9d33a66a49b5 100644
> --- a/drivers/net/wireless/intel/iwlegacy/common.c
> +++ b/drivers/net/wireless/intel/iwlegacy/common.c
> @@ -3438,9 +3438,7 @@ il_init_geos(struct il_priv *il)
>   	if (!channels)
>   		return -ENOMEM;
>
> -	rates =
> -	    kzalloc((sizeof(struct ieee80211_rate) * RATE_COUNT_LEGACY),
> -		    GFP_KERNEL);
> +	rates = kcalloc(RATE_COUNT_LEGACY, sizeof(*rates), GFP_KERNEL);
>   	if (!rates) {
>   		kfree(channels);
>   		return -ENOMEM;
> --
> 2.25.1