diff --git a/src/add-ons/kernel/drivers/disk/scsi/scsi_cd/scsi_cd.c b/src/add-ons/kernel/drivers/disk/scsi/scsi_cd/scsi_cd.c
index d62db7e0d9..ff6e9a8879 100644
--- a/src/add-ons/kernel/drivers/disk/scsi/scsi_cd/scsi_cd.c
+++ b/src/add-ons/kernel/drivers/disk/scsi/scsi_cd/scsi_cd.c
@@ -556,7 +556,7 @@ cd_ioctl(cd_handle_info *handle, int op, void *buf, size_t len)
 		case B_GET_DEVICE_SIZE:
 			res = update_capacity(device);
 			if (res == B_OK)
-				(size_t *)buf = device->capacity * device->block_size;
+				*(size_t *)buf = device->capacity * device->block_size;
 			break;
 
 		case B_GET_GEOMETRY:
diff --git a/src/add-ons/kernel/drivers/disk/scsi/scsi_dsk/scsi_dsk.c b/src/add-ons/kernel/drivers/disk/scsi/scsi_dsk/scsi_dsk.c
index 19a9d98983..09a7dd824e 100644
--- a/src/add-ons/kernel/drivers/disk/scsi/scsi_dsk/scsi_dsk.c
+++ b/src/add-ons/kernel/drivers/disk/scsi/scsi_dsk/scsi_dsk.c
@@ -193,7 +193,7 @@ das_ioctl(das_handle_info *handle, int op, void *buf, size_t len)
 		case B_GET_DEVICE_SIZE:
 			res = update_capacity(device);
 			if (res == B_OK)
-				(size_t *)buf = device->capacity * device->block_size;
+				*(size_t *)buf = device->capacity * device->block_size;
 			break;
 
 		case B_GET_GEOMETRY: