From: Dan Carpenter <dan.carpenter@xxxxxxxxxx> [ Upstream commit 1ffec389a6431782a8a28805830b6fae9bf00af1 ] The function uses "type" as an array index: q = unit[drive].disk[type]->queue; Unfortunately the bounds check on "type" isn't done until later in the function. Fix this by moving the bounds check to the start. Fixes: bf9c0538e485 ("ataflop: use a separate gendisk for each media format") Reported-by: kernel test robot <lkp@xxxxxxxxx> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/block/ataflop.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c index 104b713f4055..aed2c2a4f4ea 100644 --- a/drivers/block/ataflop.c +++ b/drivers/block/ataflop.c @@ -729,8 +729,12 @@ static int do_format(int drive, int type, struct atari_format_descr *desc) unsigned long flags; int ret; - if (type) + if (type) { type--; + if (type >= NUM_DISK_MINORS || + minor2disktype[type].drive_types > DriveType) + return -EINVAL; + } q = unit[drive].disk[type]->queue; blk_mq_freeze_queue(q); @@ -742,11 +746,6 @@ static int do_format(int drive, int type, struct atari_format_descr *desc) local_irq_restore(flags); if (type) { - if (type >= NUM_DISK_MINORS || - minor2disktype[type].drive_types > DriveType) { - ret = -EINVAL; - goto out; - } type = minor2disktype[type].index; UDT = &atari_disk_type[type]; } -- 2.30.2