[PATCH] gadget: f_thor: fix wrong file size cast

[Jaehoon Chung]

On 10/16/20 4:29 PM, Seung-Woo Kim wrote:
> Casting 32bit int value directly into 64bit unsigned type causes
> wrong value for file size equal or larger than 2GB. Fix the wrong
> file size by casting uint32_t first.
> 
> Fixes: commit 1fe9ae76b113 ("gadget: f_thor: update to support more than 4GB file as thor 5.0")
> Reported-by: Junghoon Kim <jhoon20.kim at samsung.com>
> Signed-off-by: Seung-Woo Kim <sw0312.kim at samsung.com>

Reviewed-by: Jaehoon Chung <jh80.chung at samsung.com>

Best Regards,
Jaehoon Chung

> ---
>  drivers/usb/gadget/f_thor.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/f_thor.c b/drivers/usb/gadget/f_thor.c
> index 88fc87f2e9..559ffb759e 100644
> --- a/drivers/usb/gadget/f_thor.c
> +++ b/drivers/usb/gadget/f_thor.c
> @@ -266,8 +266,8 @@ static long long int process_rqt_download(const struct rqt_box *rqt)
>  
>  	switch (rqt->rqt_data) {
>  	case RQT_DL_INIT:
> -		thor_file_size = (unsigned long long int)rqt->int_data[0] +
> -				 (((unsigned long long int)rqt->int_data[1])
> +		thor_file_size = (uint64_t)(uint32_t)rqt->int_data[0] +
> +				 (((uint64_t)(uint32_t)rqt->int_data[1])
>  				  << 32);
>  		debug("INIT: total %llu bytes\n", thor_file_size);
>  		break;
> @@ -280,8 +280,8 @@ static long long int process_rqt_download(const struct rqt_box *rqt)
>  			break;
>  		}
>  
> -		thor_file_size = (unsigned long long int)rqt->int_data[1] +
> -				 (((unsigned long long int)rqt->int_data[2])
> +		thor_file_size = (uint64_t)(uint32_t)rqt->int_data[1] +
> +				 (((uint64_t)(uint32_t)rqt->int_data[2])
>  				  << 32);
>  		memcpy(f_name, rqt->str_data[0], F_NAME_BUF_SIZE);
>  		f_name[F_NAME_BUF_SIZE] = '\0';
>