diff --git a/src/wl_window.c b/src/wl_window.c
index c4d097b7..a227c16f 100644
--- a/src/wl_window.c
+++ b/src/wl_window.c
@@ -1640,7 +1640,8 @@ static void dataDeviceHandleDataOffer(void* userData,
                                       struct wl_data_offer* offer)
 {
     _GLFWofferWayland* offers =
-        _glfw_realloc(_glfw.wl.offers, _glfw.wl.offerCount + 1);
+        _glfw_realloc(_glfw.wl.offers,
+                      sizeof(_GLFWofferWayland) * (_glfw.wl.offerCount + 1));
     if (!offers)
     {
         _glfwInputError(GLFW_OUT_OF_MEMORY, NULL);