diff --git a/contrib/oss-fuzz/libpng_read_fuzzer.cc b/contrib/oss-fuzz/libpng_read_fuzzer.cc
index bcef68c..1445f81 100644
--- a/contrib/oss-fuzz/libpng_read_fuzzer.cc
+++ b/contrib/oss-fuzz/libpng_read_fuzzer.cc
@@ -92,7 +92,11 @@
         nullptr); \
     else \
       png_destroy_read_struct(&png_handler.png_ptr, nullptr, nullptr); \
-   }
+    png_handler.png_ptr = nullptr; \
+    png_handler.row_ptr = nullptr; \
+    png_handler.info_ptr = nullptr; \
+    png_handler.end_info_ptr = nullptr;
+  }
 
   png_handler.info_ptr = png_create_info_struct(png_handler.png_ptr);
   if (!png_handler.info_ptr) {