block: Limit allocation of zone descriptors for report zones

There is no point in allocating more zone descriptors than the number of
zones a block device has for doing a zone report. Avoid doing that in
blkdev_report_zones_ioctl() by limiting the number of zone decriptors
allocated internally to process the user request.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Damien Le Moal 2018-10-12 19:08:44 +09:00 committed by Jens Axboe
parent a91e138022
commit 2e85fbaff3

View File

@ -355,8 +355,7 @@ int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode,
if (!rep.nr_zones)
return -EINVAL;
if (rep.nr_zones > INT_MAX / sizeof(struct blk_zone))
return -ERANGE;
rep.nr_zones = min(blkdev_nr_zones(bdev), rep.nr_zones);
zones = kvmalloc_array(rep.nr_zones, sizeof(struct blk_zone),
GFP_KERNEL | __GFP_ZERO);