Re: [PATCHv2] Check whether divisor is non-zero before division

[Greg KH]

On Thu, May 23, 2024 at 05:26:08PM +0800, Shichao Lai wrote:
> Since uzonesize may be zero, so judgements for non-zero are nessesary in both place.
> Previous check is moved out of loop, and one more check is added in alauda_write_lba.
> 
> 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..a6e60ef5cb0d 100644
> --- a/drivers/usb/storage/alauda.c
> +++ b/drivers/usb/storage/alauda.c
> @@ -818,6 +818,8 @@ static int alauda_write_lba(struct us_data *us, u16 lba,
>  	unsigned int blocksize = MEDIA_INFO(us).blocksize;
>  	unsigned int lba_offset = lba % uzonesize;
>  	unsigned int new_pba_offset;
> +	if (!uzonesize)
> +		return USB_STOR_TRANSPORT_ERROR;
>  	unsigned int zone = lba / uzonesize;
>  
>  	alauda_ensure_map_for_zone(us, zone);
> @@ -923,6 +925,8 @@ static int alauda_read_data(struct us_data *us, unsigned long address,
>  	unsigned int uzonesize = MEDIA_INFO(us).uzonesize;
>  	struct scatterlist *sg;
>  	int result;
> +	if (!uzonesize)
> +		return USB_STOR_TRANSPORT_ERROR;
>  
>  	/*
>  	 * Since we only read in one block at a time, we have to create
> -- 
> 2.34.1
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

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  Please read the section entitled "The canonical patch format" in the
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thanks,

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