diff --git a/util/nvmutil/nvmutil.c b/util/nvmutil/nvmutil.c
index b917776c..0185150f 100644
--- a/util/nvmutil/nvmutil.c
+++ b/util/nvmutil/nvmutil.c
@@ -1764,7 +1764,7 @@ io_args(int fd, void *mem, size_t nrw,
 	if (off < 0 || off >= gbe_file_size)
 		goto err_io_args;
 
-	if ((off_t)(off + nrw) > gbe_file_size)
+	if (nrw > (size_t)(gbe_file_size - off))
 		goto err_io_args;
 
 	if (nrw > GBE_PART_SIZE)