diff --git a/drivers/misc/cros_ec.c b/drivers/misc/cros_ec.c
index ce5fa5b..e51ac87 100644
--- a/drivers/misc/cros_ec.c
+++ b/drivers/misc/cros_ec.c
@@ -404,6 +404,8 @@
 		 */
 		if (din && in_buffer) {
 			assert(len <= din_len);
+			if (len > din_len)
+				return -ENOSPC;
 			memmove(din, in_buffer, len);
 		}
 	}