From 113ab72ed4794c193509a97d7c6d32a6886e1682 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Wed, 10 Jul 2019 13:53:10 +0900 Subject: block: Fix potential overflow in blk_report_zones() For large values of the number of zones reported and/or large zone sizes, the sector increment calculated with blk_queue_zone_sectors(q) * n in blk_report_zones() loop can overflow the unsigned int type used for the calculation as both "n" and blk_queue_zone_sectors() value are unsigned int. E.g. for a device with 256 MB zones (524288 sectors), overflow happens with 8192 or more zones reported. Changing the return type of blk_queue_zone_sectors() to sector_t, fixes this problem and avoids overflow problem for all other callers of this helper too. The same change is also applied to the bdev_zone_sectors() helper. Fixes: e76239a3748c ("block: add a report_zones method") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal Signed-off-by: Jens Axboe --- block/blk-zoned.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-zoned.c b/block/blk-zoned.c index ae7e91bd0618..3249738242b4 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -70,7 +70,7 @@ EXPORT_SYMBOL_GPL(__blk_req_zone_write_unlock); static inline unsigned int __blkdev_nr_zones(struct request_queue *q, sector_t nr_sectors) { - unsigned long zone_sectors = blk_queue_zone_sectors(q); + sector_t zone_sectors = blk_queue_zone_sectors(q); return (nr_sectors + zone_sectors - 1) >> ilog2(zone_sectors); } -- cgit v1.2.3-55-g7522