[imagedata] Handle invalid-size case in getImageData

StaticBitmapImage returned 0 to indicate an invalid image size (e.g.
integer overflow). This case was not handled properly by the caller.
With this CL we add handling for the 0-case and throw an exception.

R=jbroman@chromium.org

Bug: chromium:1027522
Change-Id: I755ea7b3e9c50a73d20487397d9862f3ca67dd74
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1932441
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Jeremy Roman <jbroman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#719197}

third_party/blink/renderer/core/layout/shapes/shape.cc

@@ -263,10 +263,12 @@ static bool ExtractImageData(Image* image,
               kDoNotRespectImageOrientation,
               Image::kDoNotClampImageToSourceRect, Image::kSyncDecode);
 
-  size_t size_in_bytes =
-      StaticBitmapImage::GetSizeInBytes(image_dest_rect, color_params);
-  if (size_in_bytes > v8::TypedArray::kMaxLength)
+  size_t size_in_bytes;
+  if (!StaticBitmapImage::GetSizeInBytes(image_dest_rect, color_params)
+           .AssignIfValid(&size_in_bytes) ||
+      size_in_bytes > v8::TypedArray::kMaxLength) {
     return false;
+  }
   ArrayBufferContents result(size_in_bytes, 1, ArrayBufferContents::kNotShared,
                              ArrayBufferContents::kZeroInitialize);
   if (result.DataLength() != size_in_bytes)

third_party/blink/renderer/modules/canvas/canvas2d/base_rendering_context_2d.cc

@@ -1588,10 +1588,13 @@ ImageData* BaseRenderingContext2D::getImageData(
   if (IsAccelerated())
     DisableAcceleration();
 
-  size_t size_in_bytes =
-      StaticBitmapImage::GetSizeInBytes(image_data_rect, color_params);
-  if (size_in_bytes > v8::TypedArray::kMaxLength)
+  size_t size_in_bytes;
+  if (!StaticBitmapImage::GetSizeInBytes(image_data_rect, color_params)
+           .AssignIfValid(&size_in_bytes) ||
+      size_in_bytes > v8::TypedArray::kMaxLength) {
+    exception_state.ThrowRangeError("Out of memory at ImageData creation");
     return nullptr;
+  }
 
   bool may_have_stray_area =
       IsAccelerated()  // GPU readback may fail silently.

third_party/blink/renderer/platform/graphics/static_bitmap_image.cc

@@ -69,13 +69,13 @@ scoped_refptr<StaticBitmapImage> StaticBitmapImage::ConvertToColorSpace(
   return UnacceleratedStaticBitmapImage::Create(skia_image);
 }
 
-size_t StaticBitmapImage::GetSizeInBytes(
+base::CheckedNumeric<size_t> StaticBitmapImage::GetSizeInBytes(
     const IntRect& rect,
     const CanvasColorParams& color_params) {
   uint8_t bytes_per_pixel = color_params.BytesPerPixel();
   base::CheckedNumeric<size_t> data_size = bytes_per_pixel;
   data_size *= rect.Size().Area();
-  return data_size.ValueOrDefault(0);
+  return data_size;
 }
 
 bool StaticBitmapImage::MayHaveStrayArea(
@@ -94,7 +94,7 @@ bool StaticBitmapImage::CopyToByteArray(
     base::span<uint8_t> dst,
     const IntRect& rect,
     const CanvasColorParams& color_params) {
-  DCHECK_EQ(dst.size(), GetSizeInBytes(rect, color_params));
+  DCHECK_EQ(dst.size(), GetSizeInBytes(rect, color_params).ValueOrDie());
 
   if (!src_image)
     return true;

third_party/blink/renderer/platform/graphics/static_bitmap_image.h

@@ -100,8 +100,9 @@ class PLATFORM_EXPORT StaticBitmapImage : public Image {
       sk_sp<SkColorSpace>,
       SkColorType = kN32_SkColorType);
 
-  static size_t GetSizeInBytes(const IntRect& rect,
-                               const CanvasColorParams& color_params);
+  static base::CheckedNumeric<size_t> GetSizeInBytes(
+      const IntRect& rect,
+      const CanvasColorParams& color_params);
 
   static bool MayHaveStrayArea(scoped_refptr<StaticBitmapImage> src_image,
                                const IntRect& rect);

third_party/blink/renderer/platform/graphics/static_bitmap_image_test.cc

@@ -27,9 +27,9 @@ TEST_F(StaticBitmapImageTest,
 
   IntRect too_big_rect(IntPoint(0, 0),
                        IntSize(1, (v8::TypedArray::kMaxLength / 4) + 1));
-  EXPECT_GT(
-      StaticBitmapImage::GetSizeInBytes(too_big_rect, CanvasColorParams()),
-      v8::TypedArray::kMaxLength);
+  EXPECT_GT(StaticBitmapImage::GetSizeInBytes(too_big_rect, CanvasColorParams())
+                .ValueOrDie(),
+            v8::TypedArray::kMaxLength);
 }
 
 }  // namespace blink

third_party/blink/web_tests/fast/canvas/bug1017918.html

@@ -7,6 +7,7 @@
 test(() => {
   let C = document.getElementById("canvas1");
   let Z = C.getContext("2d");
-  Z.getImageData(174.696924716, -3.94829667221, 6.80556775521, 291126556.736);
+  assert_throws(new RangeError(), () => Z.getImageData(174.696924716,
+    -3.94829667221, 6.80556775521, 291126556.736));
 }, "Regression test for https://crbug.com/1017918.");
 </script>