check for focaldata failure
Bug: oss-fuzz:8150
Change-Id: I061365aa5baa62405d732e92beb560a557671bf6
Reviewed-on: https://skia-review.googlesource.com/127046
Reviewed-by: Florin Malita <fmalita@chromium.org>
Commit-Queue: Mike Reed <reed@google.com>
diff --git a/src/shaders/gradients/SkTwoPointConicalGradient.cpp b/src/shaders/gradients/SkTwoPointConicalGradient.cpp
index 7f56c13..48877da 100644
--- a/src/shaders/gradients/SkTwoPointConicalGradient.cpp
+++ b/src/shaders/gradients/SkTwoPointConicalGradient.cpp
@@ -14,13 +14,13 @@
// Please see https://skia.org/dev/design/conical for how our shader works.
-void SkTwoPointConicalGradient::FocalData::set(SkScalar r0, SkScalar r1, SkMatrix& matrix) {
+bool SkTwoPointConicalGradient::FocalData::set(SkScalar r0, SkScalar r1, SkMatrix* matrix) {
fIsSwapped = false;
- fFocalX = r0 / (r0 - r1);
+ fFocalX = sk_ieee_float_divide(r0, (r0 - r1));
if (SkScalarNearlyZero(fFocalX - 1)) {
// swap r0, r1
- matrix.postTranslate(-1, 0);
- matrix.postScale(-1, 1);
+ matrix->postTranslate(-1, 0);
+ matrix->postScale(-1, 1);
std::swap(r0, r1);
fFocalX = 0; // because r0 is now 0
fIsSwapped = true;
@@ -31,22 +31,20 @@
const SkPoint to[2] = { {0, 0}, {1, 0} };
SkMatrix focalMatrix;
if (!focalMatrix.setPolyToPoly(from, to, 2)) {
- SkDEBUGFAILF("Mapping focal point failed unexpectedly for focalX = %f.\n", fFocalX);
- // We won't be able to draw the gradient; at least make sure that we initialize the
- // memory to prevent security issues.
- focalMatrix = SkMatrix::MakeScale(1, 1);
+ return false;
}
- matrix.postConcat(focalMatrix);
+ matrix->postConcat(focalMatrix);
fR1 = r1 / SkScalarAbs(1 - fFocalX); // focalMatrix has a scale of 1/(1-f)
// The following transformations are just to accelerate the shader computation by saving
// some arithmatic operations.
if (this->isFocalOnCircle()) {
- matrix.postScale(0.5, 0.5);
+ matrix->postScale(0.5, 0.5);
} else {
- matrix.postScale(fR1 / (fR1 * fR1 - 1), 1 / sqrt(SkScalarAbs(fR1 * fR1 - 1)));
+ matrix->postScale(fR1 / (fR1 * fR1 - 1), 1 / sqrt(SkScalarAbs(fR1 * fR1 - 1)));
}
- matrix.postScale(SkScalarAbs(1 - fFocalX), SkScalarAbs(1 - fFocalX)); // scale |1 - f|
+ matrix->postScale(SkScalarAbs(1 - fFocalX), SkScalarAbs(1 - fFocalX)); // scale |1 - f|
+ return true;
}
sk_sp<SkShader> SkTwoPointConicalGradient::Create(const SkPoint& c0, SkScalar r0,
@@ -77,7 +75,9 @@
FocalData focalData;
if (gradientType == Type::kFocal) {
const auto dCenter = (c0 - c1).length();
- focalData.set(r0 / dCenter, r1 / dCenter, gradientMatrix); // this may change gradientMatrix
+ if (!focalData.set(r0 / dCenter, r1 / dCenter, &gradientMatrix)) {
+ return nullptr;
+ }
}
return sk_sp<SkShader>(new SkTwoPointConicalGradient(c0, r0, c1, r1, desc,
gradientType, gradientMatrix, focalData));