From d621a99e733f135cb60dcb189806c66937348f99 Mon Sep 17 00:00:00 2001
From: Zhenqing Hu <huzq85@gmail.com>
Date: Tue, 4 Sep 2018 14:35:57 -0400
Subject: [PATCH] To fix bug #12389, which is a validation for the potential
 null pointer.

Signed-off-by: Zhenqing Hu <huzq85@gmail.com>
---
 modules/core/src/matrix_sparse.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/core/src/matrix_sparse.cpp b/modules/core/src/matrix_sparse.cpp
index a2f061cab3..a37967c222 100644
--- a/modules/core/src/matrix_sparse.cpp
+++ b/modules/core/src/matrix_sparse.cpp
@@ -228,7 +228,7 @@ void SparseMat::create(int d, const int* _sizes, int _type)
         }
     }
     int _sizes_backup[CV_MAX_DIM]; // #5991
-    if (_sizes == hdr->size)
+    if (hdr && _sizes == hdr->size)
     {
         for(int i = 0; i < d; i++ )
             _sizes_backup[i] = _sizes[i];