diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 45b00c990421..fbc356e44245 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -8213,6 +8213,12 @@ static int raid5_run(struct mddev *mddev)
 
 	/* device size must be a multiple of chunk size */
 	mddev->dev_sectors &= ~((sector_t)mddev->chunk_sectors - 1);
+	if (!mddev->dev_sectors) {
+		pr_warn("md/raid:%s: device size is smaller than one chunk\n",
+			mdname(mddev));
+		ret = -EINVAL;
+		goto abort;
+	}
 	mddev->resync_max_sectors = mddev->dev_sectors;
 
 	if (mddev->degraded > dirty_parity_disks &&
@@ -8546,6 +8552,8 @@ static int raid5_resize(struct mddev *mddev, sector_t sectors)
 	if (raid5_has_log(conf) || raid5_has_ppl(conf))
 		return -EINVAL;
 	sectors &= ~((sector_t)conf->chunk_sectors - 1);
+	if (!sectors)
+		return -EINVAL;
 	newsize = raid5_size(mddev, sectors, mddev->raid_disks);
 	if (mddev->external_size &&
 	    mddev->array_sectors > newsize)