On Fri, Oct 21, 2016 at 10:32 AM, Arnd Bergmann <a...@arndb.de> wrote:
> If sd_zbc_report_zones fails, the check for 'zone_blocks == 0'
> later in the function accesses uninitialized data:
>
> drivers/scsi/sd_zbc.c: In function ‘sd_zbc_read_zones’:
> drivers/scsi/sd_zbc.c:520:7: error: ‘zone_blocks’ may be used uninitialized
> in this function [-Werror=maybe-uninitialized]
>
> This sets it to zero, which has the desired effect of leaving
> the sd_zbc_read_zones successfully with sdkp->zone_blocks = 0.
>
> Fixes: 89d947561077 ("sd: Implement support for ZBC devices")
> Signed-off-by: Arnd Bergmann <a...@arndb.de>
> ---
> drivers/scsi/sd_zbc.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
> index 16d3fa62d8ac..d5b3bd915d9e 100644
> --- a/drivers/scsi/sd_zbc.c
> +++ b/drivers/scsi/sd_zbc.c
> @@ -455,8 +455,10 @@ static int sd_zbc_check_zone_size(struct scsi_disk *sdkp)
>
> /* Do a report zone to get the same field */
> ret = sd_zbc_report_zones(sdkp, buf, SD_ZBC_BUF_SIZE, 0);
> - if (ret)
> + if (ret) {
> + zone_blocks = 0;
> goto out;
> + }
>
> same = buf[4] & 0x0f;
> if (same > 0) {
> --
> 2.9.0
>
Reviewed-by: Shaun Tancheff <shaun.tanch...@seagate.com>
--
Shaun Tancheff
