From 5b6f1b481abb506f1e922dcbede42598c848901d Mon Sep 17 00:00:00 2001
From: Alx Sa <cmyk.student@gmail.com>
Date: Mon, 9 Mar 2026 16:21:30 +0000
Subject: [PATCH] file-data: Prevent crash with GIH and empty groups

Empty layer groups have no dimensions,
which can cause the GIH exporter to
crash when splitting cells (as it produces
negative width & height dimensions).

To prevent this, this patch initializes
potential brushes to NULL, verifies the
dimensions are positive before trying to
create GimpTempBuf with then, and prevents
a possible NULL brush from being added
to the exported brush list.
---
 app/file-data/file-data-gbr.c | 5 ++++-
 app/file-data/file-data-gih.c | 3 ++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/app/file-data/file-data-gbr.c b/app/file-data/file-data-gbr.c
index 1b30919ac1..a99b472ea0 100644
--- a/app/file-data/file-data-gbr.c
+++ b/app/file-data/file-data-gbr.c
@@ -275,6 +275,9 @@ file_gbr_drawable_to_brush (GimpDrawable        *drawable,
   width  = rect->width;
   height = rect->height;
 
+  if (width < 0 || height < 0)
+    return NULL;
+
   brush = g_object_new (GIMP_TYPE_BRUSH,
                         "name",      name,
                         "mime-type", "image/x-gimp-gbr",
@@ -421,7 +424,7 @@ file_gbr_image_to_brush (GimpImage     *image,
                          const gchar   *name,
                          gdouble        spacing)
 {
-  GimpBrush    *brush;
+  GimpBrush    *brush    = NULL;
   GimpImage    *subimage = NULL;
   GimpDrawable *drawable;
   gint          width;
diff --git a/app/file-data/file-data-gih.c b/app/file-data/file-data-gih.c
index 0d9d99f29f..19dc43dc49 100644
--- a/app/file-data/file-data-gih.c
+++ b/app/file-data/file-data-gih.c
@@ -346,7 +346,8 @@ file_gih_image_to_pipe (GimpImage   *image,
                                                   gimp_object_get_name (layer),
                                                   spacing);
 
-              brushes = g_list_prepend (brushes, brush);
+              if (brush)
+                brushes = g_list_prepend (brushes, brush);
             }
         }
     }