diff mbox series

[v3,05/11] block: Limit allocation of zone descriptors for report zones

Message ID 20181012023012.29923-6-damien.lemoal@wdc.com (mailing list archive)
State New, archived
Headers show
Series Zoned block device support improvements | expand

Commit Message

Damien Le Moal Oct. 12, 2018, 2:30 a.m. UTC 
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.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
---
 block/blk-zoned.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Hannes Reinecke Oct. 12, 2018, 7:36 a.m. UTC | #1 
On 10/12/18 4:30 AM, Damien Le Moal wrote:
> 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.
> 
> Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---
>   block/blk-zoned.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
Reviewed-by: Hannes Reinecke <hare@suse.com>

Cheers,

Hannes
diff mbox series

Patch

diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 32e377f755d8..bb4ed69f917f 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -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);