From 8772053d90e8f4580795f9d07a67f5fdaca63211 Mon Sep 17 00:00:00 2001
From: Drew Parsons <dparsons@debian.org>
Date: Tue, 13 Oct 2026 12:08:50 +0200
Subject: [PATCH] Check for null pointer in vtkMatplotlibMathTextUtilities

Forwarded: not-needed

Check if image scalar pointer is null before accessing to avoid crash on s390x.

Gbp-Pq: Name matplotlib_nullptr_s390x.patch
---
 Rendering/Matplotlib/vtkMatplotlibMathTextUtilities.cxx | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/Rendering/Matplotlib/vtkMatplotlibMathTextUtilities.cxx b/Rendering/Matplotlib/vtkMatplotlibMathTextUtilities.cxx
index 3e6b219f0..714723e5d 100644
--- a/Rendering/Matplotlib/vtkMatplotlibMathTextUtilities.cxx
+++ b/Rendering/Matplotlib/vtkMatplotlibMathTextUtilities.cxx
@@ -1023,6 +1023,12 @@ bool vtkMatplotlibMathTextUtilities::RenderOneCell(vtkImageData* image, int bbox
         return false;
       }
 
+      if (ptr == nullptr)
+      {
+	vtkErrorMacro("image returned null ScalarPointer.");
+	return false;
+      }
+
       // Background, do not load python data
       if (row > pythonRowStart || col < pythonColStart || row <= pythonRowEnd ||
         col >= pythonColEnd)
-- 
2.39.5