Re: [PATCH v5] usb-storage: Check whether the media is initialized successfully

[Alan Stern]

On Sat, May 25, 2024 at 10:10:20PM +0800, Shichao Lai wrote:
> The member "uzonesize" of struct alauda_info will remain 0
> if alauda_init_media() fails, potentially causing divide errors
> in alauda_read_data() and alauda_write_lba().
> - Add a member "media_initialized" to struct alauda_info.
> - Change a condition in alauda_check_media() to ensure the
>   first initialization.
> - Add an error check for the return value of alauda_init_media().
> 
> Reported-by: xingwei lee <xrivendell7@xxxxxxxxx>
> Reported-by: yue sun <samsun1006219@xxxxxxxxx>
> Signed-off-by: Shichao Lai <shichaorai@xxxxxxxxx>
> ---
> Changes since v1:

You mean changes since v4.  Regardless:

Reviewed-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>

> - Check the initialization of alauda_check_media()
>   which is the root cause.
> 
>  drivers/usb/storage/alauda.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/storage/alauda.c b/drivers/usb/storage/alauda.c
> index 115f05a6201a..40d34cc28344 100644
> --- a/drivers/usb/storage/alauda.c
> +++ b/drivers/usb/storage/alauda.c
> @@ -105,6 +105,8 @@ struct alauda_info {
>  	unsigned char sense_key;
>  	unsigned long sense_asc;	/* additional sense code */
>  	unsigned long sense_ascq;	/* additional sense code qualifier */
> +
> +	bool media_initialized;
>  };
>  
>  #define short_pack(lsb,msb) ( ((u16)(lsb)) | ( ((u16)(msb))<<8 ) )
> @@ -476,11 +478,12 @@ static int alauda_check_media(struct us_data *us)
>  	}
>  
>  	/* Check for media change */
> -	if (status[0] & 0x08) {
> +	if (status[0] & 0x08 || !info->media_initialized) {
>  		usb_stor_dbg(us, "Media change detected\n");
>  		alauda_free_maps(&MEDIA_INFO(us));
> -		alauda_init_media(us);
> -
> +		rc = alauda_init_media(us);
> +		if (rc == USB_STOR_TRANSPORT_GOOD)
> +			info->media_initialized = true;
>  		info->sense_key = UNIT_ATTENTION;
>  		info->sense_asc = 0x28;
>  		info->sense_ascq = 0x00;
> -- 
> 2.34.1
>