3 files changed, 7 insertions, 7 deletions
diff --git a/core/fxcrt/cfx_readonlymemorystream.cpp b/core/fxcrt/cfx_readonlymemorystream.cpp
index a01ed2e474..0a1a53a456 100644
--- a/core/fxcrt/cfx_readonlymemorystream.cpp
+++ b/core/fxcrt/cfx_readonlymemorystream.cpp
@@ -21,7 +21,7 @@ FX_FILESIZE CFX_ReadOnlyMemoryStream::GetSize() {
 bool CFX_ReadOnlyMemoryStream::ReadBlock(void* buffer,
                                          FX_FILESIZE offset,
                                          size_t size) {
-  if (offset < 0)
+  if (!buffer || offset < 0 || size == 0)
     return false;
 
   FX_SAFE_SIZE_T pos = size;
diff --git a/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp b/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
index 0109ab2985..c1fbad5f0f 100644
--- a/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlinstruction_unittest.cpp
@@ -4,10 +4,10 @@
 
 #include "core/fxcrt/xml/cfx_xmlinstruction.h"
 
+#include "core/fxcrt/cfx_readonlymemorystream.h"
 #include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
 #include "core/fxcrt/xml/cfx_xmlparser.h"
-#include "testing/fx_string_testhelpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/string_write_stream.h"
 #include "testing/test_support.h"
@@ -86,7 +86,7 @@ TEST(CFX_XMLInstructionTest, ParseAndReSave) {
       "<?acrobat http://www.xfa.org/schema/xfa-template/3.3/ Display:1 ?>\n"
       "<node></node>";
 
-  auto in_stream = pdfium::MakeRetain<CFX_BufferSeekableReadStream>(
+  auto in_stream = pdfium::MakeRetain<CFX_ReadOnlyMemoryStream>(
       pdfium::as_bytes(pdfium::make_span(input)));
 
   CFX_XMLParser parser(in_stream);
@@ -119,7 +119,7 @@ TEST(CFX_XMLInstructionTest, ParseAndReSaveInnerInstruction) {
       "<?acrobat http://www.xfa.org/schema/xfa-template/3.3/ Display:1 ?>\n"
       "</node>";
 
-  auto in_stream = pdfium::MakeRetain<CFX_BufferSeekableReadStream>(
+  auto in_stream = pdfium::MakeRetain<CFX_ReadOnlyMemoryStream>(
       pdfium::as_bytes(pdfium::make_span(input)));
 
   CFX_XMLParser parser(in_stream);
diff --git a/core/fxcrt/xml/cfx_xmlparser_unittest.cpp b/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
index c1236ce182..86d340ea83 100644
--- a/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
+++ b/core/fxcrt/xml/cfx_xmlparser_unittest.cpp
@@ -6,11 +6,11 @@
 
 #include <memory>
 
+#include "core/fxcrt/cfx_readonlymemorystream.h"
 #include "core/fxcrt/fx_codepage.h"
 #include "core/fxcrt/xml/cfx_xmldocument.h"
 #include "core/fxcrt/xml/cfx_xmlelement.h"
 #include "core/fxcrt/xml/cfx_xmlinstruction.h"
-#include "testing/fx_string_testhelpers.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "testing/test_support.h"
 #include "third_party/base/ptr_util.h"
@@ -18,8 +18,8 @@
 class CFX_XMLParserTest : public testing::Test {
  public:
   std::unique_ptr<CFX_XMLDocument> Parse(pdfium::span<const char> input) {
-    CFX_XMLParser parser(pdfium::MakeRetain<CFX_BufferSeekableReadStream>(
-        pdfium::as_bytes(input)));
+    CFX_XMLParser parser(
+        pdfium::MakeRetain<CFX_ReadOnlyMemoryStream>(pdfium::as_bytes(input)));
     return parser.Parse();
   }
 };