On Mon, Jan 04, 2021 at 09:11:47PM +0900, Damien Le Moal wrote:
commit 0ebcdd702f49aeb0ad2e2d894f8c124a0acc6e23 upstream.
For a null_blk device with zoned mode enabled is currently initialized with a number of zones equal to the device capacity divided by the zone size, without considering if the device capacity is a multiple of the zone size. If the zone size is not a divisor of the capacity, the zones end up not covering the entire capacity, potentially resulting is out of bounds accesses to the zone array.
Fix this by adding one last smaller zone with a size equal to the remainder of the disk capacity divided by the zone size if the capacity is not a multiple of the zone size. For such smaller last zone, the zone capacity is also checked so that it does not exceed the smaller zone size.
Reported-by: Naohiro Aota naohiro.aota@wdc.com Fixes: ca4b2a011948 ("null_blk: add zone support") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal damien.lemoal@wdc.com Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Signed-off-by: Jens Axboe axboe@kernel.dk
drivers/block/null_blk_zoned.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-)
That worked, thanks!
greg k-h