Fix crash when ColorSpace references itself directly.

Also fixes any problems with cycles between colorspaces.

Past fixes have solved problems with CPDF_DocPageData::GetColorSpace()
calling itself and CPDF_DocPageData::GetColorSpace() calling
CPDF_ColorSpace::Load() and vice versa. They have not solved
CPDF_ColorSpace::Load() calling itself.

This CL repurposes the |pVisited| set to ensure CPDF_ColorSpace::Load()
does not try to load a colorspace as a dependency of itself and
creates |pVisitedLocal| to ensure CPDF_DocPageData::GetColorSpace()
does not create a similar circular dependency not involving
CPDF_ColorSpace::Load().

Bug: chromium:828206
Change-Id: Ib2d0ec494be169135607f3651e0f70627b26ebd7
Reviewed-on: https://pdfium-review.googlesource.com/29810
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Henrique Nakashima <hnakashima@chromium.org>

1 files changed, 16 insertions, 0 deletions

diff --git a/core/fpdfapi/page/cpdf_docpagedata_embeddertest.cpp b/core/fpdfapi/page/cpdf_docpagedata_embeddertest.cpp
new file mode 100644
index 0000000000..5120b21c56
--- /dev/null
+++ b/core/fpdfapi/page/cpdf_docpagedata_embeddertest.cpp
@@ -0,0 +1,16 @@
+// Copyright 2018 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "testing/embedder_test.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+class CPDF_DocPageDataEmbeddertest : public EmbedderTest {};
+
+TEST_F(CPDF_DocPageDataEmbeddertest, Crasher_828206) {
+  EXPECT_TRUE(OpenDocument("bug_828206.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  RenderLoadedPage(page);
+  UnloadPage(page);
+}