diff --git a/block.c b/block.c
index 80d55ff..3e252a2 100644
--- a/block.c
+++ b/block.c
@@ -3056,13 +3056,16 @@ static int coroutine_fn bdrv_aligned_preadv(BlockDriverState *bs,
                                   align >> BDRV_SECTOR_BITS);
         if (max_nb_sectors > 0) {
             QEMUIOVector local_qiov;
+            size_t local_sectors;
+
+            max_nb_sectors = MIN(max_nb_sectors, SIZE_MAX / BDRV_SECTOR_BITS);
+            local_sectors = MIN(max_nb_sectors, nb_sectors);

             qemu_iovec_init(&local_qiov, qiov->niov);
             qemu_iovec_concat(&local_qiov, qiov, 0,
-                              max_nb_sectors * BDRV_SECTOR_SIZE);
+                              local_sectors * BDRV_SECTOR_SIZE);

-            ret = drv->bdrv_co_readv(bs, sector_num,
-                                     MIN(nb_sectors, max_nb_sectors),
+            ret = drv->bdrv_co_readv(bs, sector_num, local_sectors,
                                      &local_qiov);

             qemu_iovec_destroy(&local_qiov);