diff --git a/gdk/gdkglcontext.c b/gdk/gdkglcontext.c
index f9512b0343..7f544dc003 100644
--- a/gdk/gdkglcontext.c
+++ b/gdk/gdkglcontext.c
@@ -291,7 +291,10 @@ gdk_gl_context_upload_texture (GdkGLContext    *context,
    */
   if (stride == width * bpp)
     {
+      glPixelStorei (GL_UNPACK_ALIGNMENT, 1);
+
       glTexImage2D (texture_target, 0, GL_RGBA, width, height, 0, gl_format, gl_type, data);
+      glPixelStorei (GL_UNPACK_ALIGNMENT, 4);
     }
   else if ((!priv->use_es ||
             (priv->use_es && (priv->gl_version >= 30 || priv->has_unpack_subimage))))
@@ -302,6 +305,7 @@ gdk_gl_context_upload_texture (GdkGLContext    *context,
       glTexImage2D (texture_target, 0, GL_RGBA, width, height, 0, gl_format, gl_type, data);
 
       glPixelStorei (GL_UNPACK_ROW_LENGTH, 0);
+      glPixelStorei (GL_UNPACK_ALIGNMENT, 4);
     }
   else
     {