Re: [PATCH v2] usb-storage: Check whether divisor is non-zero before division

[Greg KH]

On Thu, May 23, 2024 at 07:34:10PM +0800, Shichao Lai wrote:
> Since uzonesize may be zero, so judgements for non-zero
> are nessesary in both place.
> 
> Changes since v1:
> - Add one more check in alauda_write_lba().
> - Move check ahead of loop in alauda_read_data().

Nit, this changes list should go below the --- line, as the
documentation asks for.


> 
> Reported-by: xingwei lee <xrivendell7@xxxxxxxxx>
> Reported-by: yue sun <samsun1006219@xxxxxxxxx>
> Signed-off-by: Shichao Lai <shichaorai@xxxxxxxxx>
> ---
>  drivers/usb/storage/alauda.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/storage/alauda.c b/drivers/usb/storage/alauda.c
> index 115f05a6201a..17c73acd3b02 100644
> --- a/drivers/usb/storage/alauda.c
> +++ b/drivers/usb/storage/alauda.c
> @@ -813,6 +813,8 @@ static int alauda_write_lba(struct us_data *us, u16 lba,
>  	unsigned char ecc[3];
>  	int i, result;
>  	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
> +	if (!uzonesize)
> +		return USB_STOR_TRANSPORT_ERROR;

Check after the list of variables please, not in the middle of them.  I
think checkpatch will complain about this, right?


>  	unsigned int zonesize = MEDIA_INFO(us).zonesize;
>  	unsigned int pagesize = MEDIA_INFO(us).pagesize;
>  	unsigned int blocksize = MEDIA_INFO(us).blocksize;
> @@ -921,6 +923,8 @@ static int alauda_read_data(struct us_data *us, unsigned long address,
>  	unsigned int blocksize = MEDIA_INFO(us).blocksize;
>  	unsigned int pagesize = MEDIA_INFO(us).pagesize;
>  	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
> +	if (!uzonesize)
> +		return USB_STOR_TRANSPORT_ERROR;

Same here, at the end of the variable list please.

thanks,

greg k-h