From 86aa568383fa1a6224fd0dc9ebd4b01072325de2 Mon Sep 17 00:00:00 2001
From: Matthew Waters <matthew@centricular.com>
Date: Wed, 6 Mar 2019 23:29:56 +1100
Subject: [PATCH] glcolorconvert: Ensure we free the internal convert object

If we only ever make it to READY, transform_caps can create an
internal convert object that will never be freed by basetransform's
stop vmethod (PAUSED->READY).
---
 ext/gl/gstglcolorconvertelement.c   | 42 +++++++++++++++++++++++++----
 gst-libs/gst/gl/gstglcolorconvert.c |  2 --
 2 files changed, 37 insertions(+), 7 deletions(-)

diff --git a/ext/gl/gstglcolorconvertelement.c b/ext/gl/gstglcolorconvertelement.c
index 9cd041def1..25e7daab90 100644
--- a/ext/gl/gstglcolorconvertelement.c
+++ b/ext/gl/gstglcolorconvertelement.c
@@ -27,6 +27,7 @@
 #include "gstglcolorconvertelement.h"
 
 GST_DEBUG_CATEGORY_STATIC (gst_gl_color_convert_element_debug);
+#define gst_gl_color_convert_element_parent_class parent_class
 #define GST_CAT_DEFAULT gst_gl_color_convert_element_debug
 
 G_DEFINE_TYPE_WITH_CODE (GstGLColorConvertElement, gst_gl_color_convert_element,
@@ -53,6 +54,9 @@ static GstFlowReturn gst_gl_color_convert_element_transform (GstBaseTransform *
     bt, GstBuffer * inbuf, GstBuffer * outbuf);
 static GstCaps *gst_gl_color_convert_element_fixate_caps (GstBaseTransform *
     bt, GstPadDirection direction, GstCaps * caps, GstCaps * othercaps);
+static GstStateChangeReturn
+gst_gl_color_convert_element_change_state (GstElement * element,
+    GstStateChange transition);
 
 static GstStaticPadTemplate gst_gl_color_convert_element_src_pad_template =
 GST_STATIC_PAD_TEMPLATE ("src",
@@ -76,9 +80,7 @@ gst_gl_color_convert_element_stop (GstBaseTransform * bt)
     convert->convert = NULL;
   }
 
-  return
-      GST_BASE_TRANSFORM_CLASS (gst_gl_color_convert_element_parent_class)->stop
-      (bt);
+  return GST_BASE_TRANSFORM_CLASS (parent_class)->stop (bt);
 }
 
 static void
@@ -100,6 +102,8 @@ gst_gl_color_convert_element_class_init (GstGLColorConvertElementClass * klass)
 
   bt_class->passthrough_on_same_caps = TRUE;
 
+  element_class->change_state = gst_gl_color_convert_element_change_state;
+
   gst_element_class_add_static_pad_template (element_class,
       &gst_gl_color_convert_element_src_pad_template);
   gst_element_class_add_static_pad_template (element_class,
@@ -178,8 +182,7 @@ gst_gl_color_convert_element_decide_allocation (GstBaseTransform * trans,
   GstGLColorConvertElement *convert = GST_GL_COLOR_CONVERT_ELEMENT (trans);
 
   /* get gl context */
-  if (!GST_BASE_TRANSFORM_CLASS
-      (gst_gl_color_convert_element_parent_class)->decide_allocation (trans,
+  if (!GST_BASE_TRANSFORM_CLASS (parent_class)->decide_allocation (trans,
           query))
     return FALSE;
 
@@ -237,3 +240,32 @@ gst_gl_color_convert_element_fixate_caps (GstBaseTransform *
 
   return gst_gl_color_convert_fixate_caps (context, direction, caps, othercaps);
 }
+
+static GstStateChangeReturn
+gst_gl_color_convert_element_change_state (GstElement * element,
+    GstStateChange transition)
+{
+  GstGLColorConvertElement *convert = GST_GL_COLOR_CONVERT_ELEMENT (element);
+  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
+
+  GST_DEBUG_OBJECT (convert, "changing state: %s => %s",
+      gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
+      gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));
+
+  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
+  if (ret == GST_STATE_CHANGE_FAILURE)
+    return ret;
+
+  switch (transition) {
+    case GST_STATE_CHANGE_READY_TO_NULL:
+      if (convert->convert) {
+        gst_object_unref (convert->convert);
+        convert->convert = NULL;
+      }
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+}
diff --git a/gst-libs/gst/gl/gstglcolorconvert.c b/gst-libs/gst/gl/gstglcolorconvert.c
index c319709fde..9fa123a42d 100644
--- a/gst-libs/gst/gl/gstglcolorconvert.c
+++ b/gst-libs/gst/gl/gstglcolorconvert.c
@@ -523,8 +523,6 @@ gst_gl_color_convert_finalize (GObject * object)
     convert->context = NULL;
   }
 
-  GST_ERROR_OBJECT (convert, "finalize");
-
   G_OBJECT_CLASS (gst_gl_color_convert_parent_class)->finalize (object);
 }