Handle image mask continuous loading correctly

When image mask doesn't need multi-steps to load, ContinueLoadMaskDIB()
will return LoadState::kFail as result. For this case, the loading
should continue as usual instead of aborting.

BUG=pdfium:1087

Change-Id: I5c43a67e43469ac7febca4c0cf1faa96ee105206
Reviewed-on: https://pdfium-review.googlesource.com/33310
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Wei Li <weili@chromium.org>

2 files changed, 13 insertions, 2 deletions

diff --git a/core/fpdfapi/render/cpdf_dibsource.cpp b/core/fpdfapi/render/cpdf_dibsource.cpp
index 3a4ca02cc2..d1eba2e467 100644
--- a/core/fpdfapi/render/cpdf_dibsource.cpp
+++ b/core/fpdfapi/render/cpdf_dibsource.cpp
@@ -323,8 +323,10 @@ CPDF_DIBSource::LoadState CPDF_DIBSource::ContinueLoadDIBSource(
 
   LoadState iContinueStatus = LoadState::kSuccess;
   if (m_bHasMask) {
-    iContinueStatus = ContinueLoadMaskDIB(pPause);
-    m_Status = LoadState::kContinue;
+    if (ContinueLoadMaskDIB(pPause) == LoadState::kContinue) {
+      iContinueStatus = LoadState::kContinue;
+      m_Status = LoadState::kContinue;
+    }
   }
   if (iContinueStatus == LoadState::kContinue)
     return LoadState::kContinue;
diff --git a/core/fpdfapi/render/fpdf_render_loadimage_embeddertest.cpp b/core/fpdfapi/render/fpdf_render_loadimage_embeddertest.cpp
index 5103d787bd..e3bd297afb 100644
--- a/core/fpdfapi/render/fpdf_render_loadimage_embeddertest.cpp
+++ b/core/fpdfapi/render/fpdf_render_loadimage_embeddertest.cpp
@@ -40,3 +40,12 @@ TEST_F(FPDFRenderLoadImageEmbeddertest, Bug_603518) {
   CompareBitmap(bitmap.get(), 749, 749, "b9e75190cdc5edf0069a408744ca07dc");
   UnloadPage(page);
 }
+
+TEST_F(FPDFRenderLoadImageEmbeddertest, Bug_1087) {
+  EXPECT_TRUE(OpenDocument("bug_1087.pdf"));
+  FPDF_PAGE page = LoadPage(0);
+  ASSERT_TRUE(page);
+  ScopedFPDFBitmap bitmap = RenderLoadedPage(page);
+  CompareBitmap(bitmap.get(), 548, 238, "2aac40afa121feb0f38883cb04a55001");
+  UnloadPage(page);
+}