Re: wifi: iwlwifi: calib: Refactor iwl_calib_result usage for clarity

[Kalle Valo]

Kees Cook <keescook@xxxxxxxxxxxx> wrote:

> In preparation for FORTIFY_SOURCE performing run-time destination buffer
> bounds checking for memcpy(), refactor the use of struct iwl_calib_result:
> 
> - Have struct iwl_calib_result contain struct iwl_calib_cmd since
>   functions expect to operate on the "data" flex array in "cmd", which
>   follows the "hdr" member.
> - Switch argument passing around to use struct iwl_calib_cmd instead of
>   struct iwl_calib_hdr to prepare functions to see the "data" member.
> - Change iwl_calib_set()'s "len" argument to a size_t since it is always
>   unsigned and is normally receiving the output of sizeof().
> - Add an explicit length sanity check in iwl_calib_set().
> - Adjust the memcpy() to avoid copying across the now visible composite
>   flex array structure.
> 
> This avoids the future run-time warning:
> 
>   memcpy: detected field-spanning write (size 8) of single field "&res->hdr" (size 4)
> 
> Cc: Luca Coelho <luciano.coelho@xxxxxxxxx>
> Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Jakub Kicinski <kuba@xxxxxxxxxx>
> Cc: Lee Jones <lee.jones@xxxxxxxxxx>
> Cc: Johannes Berg <johannes.berg@xxxxxxxxx>
> Cc: linux-wireless@xxxxxxxxxxxxxxx
> Cc: netdev@xxxxxxxxxxxxxxx
> Reported-by: Andy Lavr <andy.lavr@xxxxxxxxx>
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Patch applied to wireless-next.git, thanks.

0d24201f47c4 wifi: iwlwifi: calib: Refactor iwl_calib_result usage for clarity

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20220901204558.2256458-1-keescook@xxxxxxxxxxxx/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches