From 7b38e3cf75296c749c843fa89af14f70f4e4b2db Mon Sep 17 00:00:00 2001 From: fmalita Date: Thu, 26 May 2016 11:13:52 -0700 Subject: Fix int32 overflow in LinearGradientContext::shade4_dx_clamp The unconditional increment in shade4_dx_clamp can overflow int32 => n == SK_MinS32 => count ~= SK_MinS32 => we skip the main shader loop 'cause count < 0 R=reed@google.com,mtklein@google.com BUG=chromium:599458 GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2010843002 Review-Url: https://codereview.chromium.org/2010843002 --- tests/GradientTest.cpp | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'tests') diff --git a/tests/GradientTest.cpp b/tests/GradientTest.cpp index ac55d9934e..7add42d875 100644 --- a/tests/GradientTest.cpp +++ b/tests/GradientTest.cpp @@ -234,6 +234,25 @@ static void test_two_point_conical_zero_radius(skiatest::Reporter* reporter) { REPORTER_ASSERT(reporter, SkGetPackedR32(centerPMColor) == 0); } +// http://crbug.com/599458 +static void test_clamping_overflow(skiatest::Reporter*) { + SkPaint p; + const SkColor colors[] = { SK_ColorRED, SK_ColorGREEN }; + const SkPoint pts1[] = { SkPoint::Make(1001, 1000001), SkPoint::Make(1000.99f, 1000000) }; + + p.setShader(SkGradientShader::MakeLinear(pts1, colors, nullptr, 2, SkShader::kClamp_TileMode)); + + sk_sp surface(SkSurface::MakeRasterN32Premul(50, 50)); + surface->getCanvas()->scale(100, 100); + surface->getCanvas()->drawPaint(p); + + const SkPoint pts2[] = { SkPoint::Make(10000.99f, 1000000), SkPoint::Make(10001, 1000001) }; + p.setShader(SkGradientShader::MakeLinear(pts2, colors, nullptr, 2, SkShader::kClamp_TileMode)); + surface->getCanvas()->drawPaint(p); + + // Passes if we don't trigger asserts. +} + DEF_TEST(Gradient, reporter) { TestGradientShaders(reporter); TestConstantGradient(reporter); @@ -241,4 +260,5 @@ DEF_TEST(Gradient, reporter) { test_nearly_vertical(reporter); test_linear_fuzz(reporter); test_two_point_conical_zero_radius(reporter); + test_clamping_overflow(reporter); } -- cgit v1.2.3