[gnome-software: 6/7] gs-app: Change gs_app_get_version_history() to return a ref

[Philip Withnall <pwithnall src gnome org>]

commit a00ab0a87799c62211efdcfef16849c905238899
Author: Philip Withnall <pwithnall endlessos org>
Date:   Thu Apr 29 15:52:43 2021 +0100

    gs-app: Change gs_app_get_version_history() to return a ref
    
    It seems the version history can be updated from a separate thread while
    refreshing. This can cause crashes if the UI thread queries the version
    history, then it’s updated from another thread, then the UI thread
    starts iterating over the `GPtrArray` it queried — which has since been
    freed.
    
    Fix that by returning a strong ref to the `GPtrArray`, and doing so
    under the app’s mutex.
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>
    
    Fixes: #1227

 lib/gs-app.c                        | 11 ++++++++---
 src/gs-app-version-history-dialog.c |  2 +-
 src/gs-details-page.c               |  2 +-
 3 files changed, 10 insertions(+), 5 deletions(-)
---
diff --git a/lib/gs-app.c b/lib/gs-app.c
index f52bb2c76..877ed1008 100644
--- a/lib/gs-app.c
+++ b/lib/gs-app.c
@@ -5353,17 +5353,22 @@ gs_app_set_update_permissions (GsApp *app, GsAppPermissions update_permissions)
  * Gets the list of past releases for an application (including the latest
  * one).
  *
- * Returns: (element-type AsRelease) (transfer none) (nullable): a list, or
+ * Returns: (element-type AsRelease) (transfer container) (nullable): a list, or
  *     %NULL if the version history is not known
  *
- * Since: 40
+ * Since: 41
  **/
 GPtrArray *
 gs_app_get_version_history (GsApp *app)
 {
        GsAppPrivate *priv = gs_app_get_instance_private (app);
+       g_autoptr(GMutexLocker) locker = NULL;
        g_return_val_if_fail (GS_IS_APP (app), NULL);
-       return priv->version_history;
+
+       locker = g_mutex_locker_new (&priv->mutex);
+       if (priv->version_history == NULL)
+               return NULL;
+       return g_ptr_array_ref (priv->version_history);
 }
 
 /**
diff --git a/src/gs-app-version-history-dialog.c b/src/gs-app-version-history-dialog.c
index 5262596a2..8b61b7c2b 100644
--- a/src/gs-app-version-history-dialog.c
+++ b/src/gs-app-version-history-dialog.c
@@ -28,7 +28,7 @@ static void
 populate_version_history (GsAppVersionHistoryDialog *dialog,
                          GsApp                     *app)
 {
-       GPtrArray *version_history;
+       g_autoptr(GPtrArray) version_history = NULL;
 
        /* remove previous */
        gs_container_remove_all (GTK_CONTAINER (dialog->listbox));
diff --git a/src/gs-details-page.c b/src/gs-details-page.c
index 6f8520f76..6ac309da9 100644
--- a/src/gs-details-page.c
+++ b/src/gs-details-page.c
@@ -1237,7 +1237,7 @@ gs_details_page_refresh_all (GsDetailsPage *self)
        guint64 user_integration_bf;
        gboolean show_support_box = FALSE;
        g_autofree gchar *origin = NULL;
-       GPtrArray *version_history;
+       g_autoptr(GPtrArray) version_history = NULL;
        guint icon_size;
 
        /* change widgets */