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@xxxxxxxxxxxxxxx
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
---
block/blk-zoned.c | 2 +-
include/linux/blkdev.h | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/block/blk-zoned.c b/block/blk-zoned.c
index 79ad269b545d..6c503824ba3f 100644
--- a/block/blk-zoned.c
+++ b/block/blk-zoned.c
@@ -73,7 +73,7 @@ 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 5ace0bb77213..760668ed555a 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -686,7 +686,7 @@ 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;
}
@@ -1434,7 +1434,7 @@ 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);
--
2.21.0
