From: Damien Le Moal Date: Wed, 10 Jul 2019 04:53:10 +0000 (+0900) Subject: block: Fix potential overflow in blk_report_zones() X-Git-Tag: v5.1.20~44 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c1bbef41db5816913e3e1fa10f2c4ddae8dd0b50;p=thirdparty%2Fkernel%2Fstable.git block: Fix potential overflow in blk_report_zones() commit 113ab72ed4794c193509a97d7c6d32a6886e1682 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- diff --git a/block/blk-zoned.c b/block/blk-zoned.c index 2d98803faec24..6ea455b62cb4f 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -69,7 +69,7 @@ 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); } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 317ab30d29046..08a84d1301209 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -662,7 +662,7 @@ static inline bool blk_queue_is_zoned(struct request_queue *q) } } -static inline unsigned int blk_queue_zone_sectors(struct request_queue *q) +static inline sector_t blk_queue_zone_sectors(struct request_queue *q) { return blk_queue_is_zoned(q) ? q->limits.chunk_sectors : 0; } @@ -1400,7 +1400,7 @@ static inline bool bdev_is_zoned(struct block_device *bdev) return false; } -static inline unsigned int bdev_zone_sectors(struct block_device *bdev) +static inline sector_t bdev_zone_sectors(struct block_device *bdev) { struct request_queue *q = bdev_get_queue(bdev);