mxfdemux: Store GstMXFDemuxEssenceTrack in their own fixed allocation

Origin: https://gitlab.freedesktop.org/gstreamer/gstreamer/-/commit/7dfaa57b6f9b55f17ffe824bd8988bb71ae11353
Bug-Debian: https://bugs.debian.org/1056101
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2023-44446

Previously they were stored inline inside a GArray, but as references to
the tracks were stored in various other places although the array could
still be updated (and reallocated!), this could lead to dangling
references in various places.

Instead now store them in a GPtrArray in their own allocation so each
track's memory position stays fixed.

Fixes ZDI-CAN-22299

Fixes https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/3055

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5638>

Gbp-Pq: Name CVE-2023-44446.patch

diff --git a/gst/mxf/mxfdemux.c b/gst/mxf/mxfdemux.c
index eefdf81734aa2fee79cba46d382b6bb79737279c..3275a093e9de9d24259277c77e68d99aa21b3390 100644 (file)
--- a/gst/mxf/mxfdemux.c
+++ b/gst/mxf/mxfdemux.c
@@ -154,10 +154,25 @@ gst_mxf_demux_partition_free (GstMXFDemuxPartition * partition)
 }
 
 static void
-gst_mxf_demux_reset_mxf_state (GstMXFDemux * demux)
+gst_mxf_demux_essence_track_free (GstMXFDemuxEssenceTrack * t)
 {
-  guint i;
+  if (t->offsets)
+    g_array_free (t->offsets, TRUE);
+
+  g_free (t->mapping_data);
+
+  if (t->tags)
+    gst_tag_list_unref (t->tags);
+
+  if (t->caps)
+    gst_caps_unref (t->caps);
+
+  g_free (t);
+}
 
+static void
+gst_mxf_demux_reset_mxf_state (GstMXFDemux * demux)
+{
   GST_DEBUG_OBJECT (demux, "Resetting MXF state");
 
   g_list_foreach (demux->partitions, (GFunc) gst_mxf_demux_partition_free,
@@ -166,23 +181,7 @@ gst_mxf_demux_reset_mxf_state (GstMXFDemux * demux)
   demux->partitions = NULL;
 
   demux->current_partition = NULL;
-
-  for (i = 0; i < demux->essence_tracks->len; i++) {
-    GstMXFDemuxEssenceTrack *t =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
-
-    if (t->offsets)
-      g_array_free (t->offsets, TRUE);
-
-    g_free (t->mapping_data);
-
-    if (t->tags)
-      gst_tag_list_unref (t->tags);
-
-    if (t->caps)
-      gst_caps_unref (t->caps);
-  }
-  g_array_set_size (demux->essence_tracks, 0);
+  g_ptr_array_set_size (demux->essence_tracks, 0);
 }
 
 static void
@@ -200,7 +199,7 @@ gst_mxf_demux_reset_linked_metadata (GstMXFDemux * demux)
 
   for (i = 0; i < demux->essence_tracks->len; i++) {
     GstMXFDemuxEssenceTrack *track =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+        g_ptr_array_index (demux->essence_tracks, i);
 
     track->source_package = NULL;
     track->source_track = NULL;
@@ -713,8 +712,7 @@ gst_mxf_demux_update_essence_tracks (GstMXFDemux * demux)
 
       for (k = 0; k < demux->essence_tracks->len; k++) {
         GstMXFDemuxEssenceTrack *tmp =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack,
-            k);
+            g_ptr_array_index (demux->essence_tracks, k);
 
         if (tmp->track_number == track->parent.track_number &&
             tmp->body_sid == edata->body_sid) {
@@ -732,24 +730,23 @@ gst_mxf_demux_update_essence_tracks (GstMXFDemux * demux)
       }
 
       if (!etrack) {
-        GstMXFDemuxEssenceTrack tmp;
+        GstMXFDemuxEssenceTrack *tmp = g_new0 (GstMXFDemuxEssenceTrack, 1);
 
-        memset (&tmp, 0, sizeof (tmp));
-        tmp.body_sid = edata->body_sid;
-        tmp.index_sid = edata->index_sid;
-        tmp.track_number = track->parent.track_number;
-        tmp.track_id = track->parent.track_id;
-        memcpy (&tmp.source_package_uid, &package->parent.package_uid, 32);
+        tmp->body_sid = edata->body_sid;
+        tmp->index_sid = edata->index_sid;
+        tmp->track_number = track->parent.track_number;
+        tmp->track_id = track->parent.track_id;
+        memcpy (&tmp->source_package_uid, &package->parent.package_uid, 32);
 
         if (demux->current_partition->partition.body_sid == edata->body_sid &&
             demux->current_partition->partition.body_offset == 0)
-          tmp.position = 0;
+          tmp->position = 0;
         else
-          tmp.position = -1;
+          tmp->position = -1;
 
-        g_array_append_val (demux->essence_tracks, tmp);
+        g_ptr_array_add (demux->essence_tracks, tmp);
         etrack =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack,
+            g_ptr_array_index (demux->essence_tracks,
             demux->essence_tracks->len - 1);
         new = TRUE;
       }
@@ -876,13 +873,7 @@ gst_mxf_demux_update_essence_tracks (GstMXFDemux * demux)
 
     next:
       if (new) {
-        g_free (etrack->mapping_data);
-        if (etrack->tags)
-          gst_tag_list_unref (etrack->tags);
-        if (etrack->caps)
-          gst_caps_unref (etrack->caps);
-
-        g_array_remove_index (demux->essence_tracks,
+        g_ptr_array_remove_index (demux->essence_tracks,
             demux->essence_tracks->len - 1);
       }
     }
@@ -895,7 +886,7 @@ gst_mxf_demux_update_essence_tracks (GstMXFDemux * demux)
 
   for (i = 0; i < demux->essence_tracks->len; i++) {
     GstMXFDemuxEssenceTrack *etrack =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+        g_ptr_array_index (demux->essence_tracks, i);
 
     if (!etrack->source_package || !etrack->source_track || !etrack->caps) {
       GST_ERROR_OBJECT (demux, "Failed to update essence track %u", i);
@@ -1117,7 +1108,7 @@ gst_mxf_demux_update_tracks (GstMXFDemux * demux)
 
     for (k = 0; k < demux->essence_tracks->len; k++) {
       GstMXFDemuxEssenceTrack *tmp =
-          &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, k);
+          g_ptr_array_index (demux->essence_tracks, k);
 
       if (tmp->source_package == source_package &&
           tmp->source_track == source_track) {
@@ -1598,8 +1589,7 @@ gst_mxf_demux_pad_set_component (GstMXFDemux * demux, GstMXFDemuxPad * pad,
   pad->current_essence_track = NULL;
 
   for (k = 0; k < demux->essence_tracks->len; k++) {
-    GstMXFDemuxEssenceTrack *tmp =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, k);
+    GstMXFDemuxEssenceTrack *tmp = g_ptr_array_index (demux->essence_tracks, k);
 
     if (tmp->source_package == source_package &&
         tmp->source_track == source_track) {
@@ -1729,7 +1719,7 @@ gst_mxf_demux_handle_generic_container_essence_element (GstMXFDemux * demux,
 
   for (i = 0; i < demux->essence_tracks->len; i++) {
     GstMXFDemuxEssenceTrack *tmp =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+        g_ptr_array_index (demux->essence_tracks, i);
 
     if (tmp->body_sid == demux->current_partition->partition.body_sid &&
         (tmp->track_number == track_number || tmp->track_number == 0)) {
@@ -2654,7 +2644,7 @@ gst_mxf_demux_handle_klv_packet (GstMXFDemux * demux, const MXFUL * key,
 
       for (i = 0; i < demux->essence_tracks->len; i++) {
         GstMXFDemuxEssenceTrack *etrack =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+            g_ptr_array_index (demux->essence_tracks, i);
 
         if (etrack->body_sid != demux->current_partition->partition.body_sid)
           continue;
@@ -2717,7 +2707,7 @@ gst_mxf_demux_handle_klv_packet (GstMXFDemux * demux, const MXFUL * key,
       guint i;
       for (i = 0; i < demux->essence_tracks->len; i++) {
         GstMXFDemuxEssenceTrack *etrack =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+            g_ptr_array_index (demux->essence_tracks, i);
 
         if (etrack->body_sid != demux->current_partition->partition.body_sid)
           continue;
@@ -2912,7 +2902,7 @@ from_index:
 
     for (i = 0; i < demux->essence_tracks->len; i++) {
       GstMXFDemuxEssenceTrack *t =
-          &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+          g_ptr_array_index (demux->essence_tracks, i);
 
       if (index_start_position != -1 && t == etrack)
         t->position = index_start_position;
@@ -2935,8 +2925,7 @@ from_index:
       if (ret == GST_FLOW_EOS) {
         for (i = 0; i < demux->essence_tracks->len; i++) {
           GstMXFDemuxEssenceTrack *t =
-              &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack,
-              i);
+              g_ptr_array_index (demux->essence_tracks, i);
 
           if (t->position > 0)
             t->duration = t->position;
@@ -3018,7 +3007,7 @@ gst_mxf_demux_pull_and_handle_klv_packet (GstMXFDemux * demux)
 
     for (i = 0; i < demux->essence_tracks->len; i++) {
       GstMXFDemuxEssenceTrack *t =
-          &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+          g_ptr_array_index (demux->essence_tracks, i);
 
       if (t->position > 0)
         t->duration = t->position;
@@ -3626,7 +3615,7 @@ gst_mxf_demux_seek_push (GstMXFDemux * demux, GstEvent * event)
 
   for (i = 0; i < demux->essence_tracks->len; i++) {
     GstMXFDemuxEssenceTrack *t =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+        g_ptr_array_index (demux->essence_tracks, i);
     t->position = -1;
   }
 
@@ -3999,8 +3988,7 @@ gst_mxf_demux_seek_pull (GstMXFDemux * demux, GstEvent * event)
   }
 
   for (i = 0; i < demux->essence_tracks->len; i++) {
-    GstMXFDemuxEssenceTrack *t =
-        &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+    GstMXFDemuxEssenceTrack *t = g_ptr_array_index (demux->essence_tracks, i);
     t->position = -1;
   }
 
@@ -4282,7 +4270,7 @@ gst_mxf_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
 
       for (i = 0; i < demux->essence_tracks->len; i++) {
         GstMXFDemuxEssenceTrack *t =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack, i);
+            g_ptr_array_index (demux->essence_tracks, i);
 
         if (t->position > 0)
           t->duration = t->position;
@@ -4323,8 +4311,7 @@ gst_mxf_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
 
           for (i = 0; i < demux->essence_tracks->len; i++) {
             GstMXFDemuxEssenceTrack *etrack =
-                &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack,
-                i);
+                g_ptr_array_index (demux->essence_tracks, i);
             etrack->position = -1;
           }
           ret = TRUE;
@@ -4348,8 +4335,7 @@ gst_mxf_demux_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
 
       for (i = 0; i < demux->essence_tracks->len; i++) {
         GstMXFDemuxEssenceTrack *t =
-            &g_array_index (demux->essence_tracks, GstMXFDemuxEssenceTrack,
-            i);
+            g_ptr_array_index (demux->essence_tracks, i);
         t->position = -1;
       }
       demux->current_partition = NULL;
@@ -4622,7 +4608,7 @@ gst_mxf_demux_finalize (GObject * object)
 
   g_ptr_array_free (demux->src, TRUE);
   demux->src = NULL;
-  g_array_free (demux->essence_tracks, TRUE);
+  g_ptr_array_free (demux->essence_tracks, TRUE);
   demux->essence_tracks = NULL;
 
   g_hash_table_destroy (demux->metadata);
@@ -4699,8 +4685,8 @@ gst_mxf_demux_init (GstMXFDemux * demux)
   g_rw_lock_init (&demux->metadata_lock);
 
   demux->src = g_ptr_array_new ();
-  demux->essence_tracks =
-      g_array_new (FALSE, FALSE, sizeof (GstMXFDemuxEssenceTrack));
+  demux->essence_tracks = g_ptr_array_new_with_free_func ((GDestroyNotify)
+      gst_mxf_demux_essence_track_free);
 
   gst_segment_init (&demux->segment, GST_FORMAT_TIME);
 

diff --git a/gst/mxf/mxfdemux.h b/gst/mxf/mxfdemux.h
index aac3e67d06298de5b3ac51e308f3102e227b5953..a452980eea1bad8291d7a7f309ab96447f51385d 100644 (file)
--- a/gst/mxf/mxfdemux.h
+++ b/gst/mxf/mxfdemux.h
@@ -182,7 +182,7 @@ struct _GstMXFDemux
   GList *partitions;
   GstMXFDemuxPartition *current_partition;
 
-  GArray *essence_tracks;
+  GPtrArray *essence_tracks;
 
   GList *pending_index_table_segments;
   GList *index_tables; /* one per BodySID / IndexSID */